pbx.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2008, Digium, Inc.
 *
 * Mark Spencer <markster@digium.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*! \file
 *
 * \brief Core PBX routines.
 *
 * \author Mark Spencer <markster@digium.com>
 */
#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision: 211569 $")

#include "asterisk/_private.h"
#include "asterisk/paths.h"   /* use ast_config_AST_SYSTEM_NAME */
#include <ctype.h>
#include <time.h>
#include <sys/time.h>
#if defined(HAVE_SYSINFO)
#include <sys/sysinfo.h>
#endif
#if defined(SOLARIS)
#include <sys/loadavg.h>
#endif

#include "asterisk/lock.h"
#include "asterisk/cli.h"
#include "asterisk/pbx.h"
#include "asterisk/channel.h"
#include "asterisk/file.h"
#include "asterisk/callerid.h"
#include "asterisk/cdr.h"
#include "asterisk/config.h"
#include "asterisk/term.h"
#include "asterisk/time.h"
#include "asterisk/manager.h"
#include "asterisk/ast_expr.h"
#include "asterisk/linkedlists.h"
#define  SAY_STUBS   /* generate declarations and stubs for say methods */
#include "asterisk/say.h"
#include "asterisk/utils.h"
#include "asterisk/causes.h"
#include "asterisk/musiconhold.h"
#include "asterisk/app.h"
#include "asterisk/devicestate.h"
#include "asterisk/stringfields.h"
#include "asterisk/event.h"
#include "asterisk/hashtab.h"
#include "asterisk/module.h"
#include "asterisk/indications.h"
#include "asterisk/taskprocessor.h"

/*!
 * \note I M P O R T A N T :
 *
 *    The speed of extension handling will likely be among the most important
 * aspects of this PBX.  The switching scheme as it exists right now isn't
 * terribly bad (it's O(N+M), where N is the # of extensions and M is the avg #
 * of priorities, but a constant search time here would be great ;-)
 *
 * A new algorithm to do searching based on a 'compiled' pattern tree is introduced
 * here, and shows a fairly flat (constant) search time, even for over
 * 10000 patterns. 
 *
 * Also, using a hash table for context/priority name lookup can help prevent
 * the find_extension routines from absorbing exponential cpu cycles as the number 
 * of contexts/priorities grow. I've previously tested find_extension with red-black trees, 
 * which have O(log2(n)) speed. Right now, I'm using hash tables, which do 
 * searches (ideally) in O(1) time. While these techniques do not yield much 
 * speed in small dialplans, they are worth the trouble in large dialplans.
 *
 */

#ifdef LOW_MEMORY
#define EXT_DATA_SIZE 256
#else
#define EXT_DATA_SIZE 8192
#endif

#define SWITCH_DATA_LENGTH 256

#define VAR_BUF_SIZE 4096

#define  VAR_NORMAL     1
#define  VAR_SOFTTRAN   2
#define  VAR_HARDTRAN   3

#define BACKGROUND_SKIP    (1 << 0)
#define BACKGROUND_NOANSWER   (1 << 1)
#define BACKGROUND_MATCHEXTEN (1 << 2)
#define BACKGROUND_PLAYBACK   (1 << 3)

AST_APP_OPTIONS(background_opts, {
   AST_APP_OPTION('s', BACKGROUND_SKIP),
   AST_APP_OPTION('n', BACKGROUND_NOANSWER),
   AST_APP_OPTION('m', BACKGROUND_MATCHEXTEN),
   AST_APP_OPTION('p', BACKGROUND_PLAYBACK),
});

#define WAITEXTEN_MOH      (1 << 0)
#define WAITEXTEN_DIALTONE (1 << 1)

AST_APP_OPTIONS(waitexten_opts, {
   AST_APP_OPTION_ARG('m', WAITEXTEN_MOH, 0),
   AST_APP_OPTION_ARG('d', WAITEXTEN_DIALTONE, 0),
});

struct ast_context;
struct ast_app;

static struct ast_taskprocessor *device_state_tps;

AST_THREADSTORAGE(switch_data);

/*!
   \brief ast_exten: An extension
   The dialplan is saved as a linked list with each context
   having it's own linked list of extensions - one item per
   priority.
*/
struct ast_exten {
   char *exten;         /*!< Extension name */
   int matchcid;        /*!< Match caller id ? */
   const char *cidmatch;      /*!< Caller id to match for this extension */
   int priority;        /*!< Priority */
   const char *label;      /*!< Label */
   struct ast_context *parent;   /*!< The context this extension belongs to  */
   const char *app;     /*!< Application to execute */
   struct ast_app *cached_app;     /*!< Cached location of application */
   void *data;       /*!< Data to use (arguments) */
   void (*datad)(void *);     /*!< Data destructor */
   struct ast_exten *peer;    /*!< Next higher priority with our extension */
   struct ast_hashtab *peer_table;    /*!< Priorities list in hashtab form -- only on the head of the peer list */
   struct ast_hashtab *peer_label_table; /*!< labeled priorities in the peers -- only on the head of the peer list */
   const char *registrar;     /*!< Registrar */
   struct ast_exten *next;    /*!< Extension with a greater ID */
   char stuff[0];
};

/*! \brief ast_include: include= support in extensions.conf */
struct ast_include {
   const char *name;
   const char *rname;         /*!< Context to include */
   const char *registrar;        /*!< Registrar */
   int hastime;            /*!< If time construct exists */
   struct ast_timing timing;               /*!< time construct */
   struct ast_include *next;     /*!< Link them together */
   char stuff[0];
};

/*! \brief ast_sw: Switch statement in extensions.conf */
struct ast_sw {
   char *name;
   const char *registrar;        /*!< Registrar */
   char *data;          /*!< Data load */
   int eval;
   AST_LIST_ENTRY(ast_sw) list;
   char stuff[0];
};

/*! \brief ast_ignorepat: Ignore patterns in dial plan */
struct ast_ignorepat {
   const char *registrar;
   struct ast_ignorepat *next;
   const char pattern[0];
};

/*! \brief match_char: forms a syntax tree for quick matching of extension patterns */
struct match_char
{
   int is_pattern; /* the pattern started with '_' */
   int deleted;    /* if this is set, then... don't return it */
   char *x;       /* the pattern itself-- matches a single char */
   int specificity; /* simply the strlen of x, or 10 for X, 9 for Z, and 8 for N; and '.' and '!' will add 11 ? */
   struct match_char *alt_char;
   struct match_char *next_char;
   struct ast_exten *exten; /* attached to last char of a pattern for exten */
};

struct scoreboard  /* make sure all fields are 0 before calling new_find_extension */
{
   int total_specificity;
   int total_length;
   char last_char;   /* set to ! or . if they are the end of the pattern */
   int canmatch;     /* if the string to match was just too short */
   struct match_char *node;
   struct ast_exten *canmatch_exten;
   struct ast_exten *exten;
};

/*! \brief ast_context: An extension context */
struct ast_context {
   ast_rwlock_t lock;         /*!< A lock to prevent multiple threads from clobbering the context */
   struct ast_exten *root;       /*!< The root of the list of extensions */
   struct ast_hashtab *root_table;            /*!< For exact matches on the extensions in the pattern tree, and for traversals of the pattern_tree  */
   struct match_char *pattern_tree;        /*!< A tree to speed up extension pattern matching */
   struct ast_context *next;     /*!< Link them together */
   struct ast_include *includes;    /*!< Include other contexts */
   struct ast_ignorepat *ignorepats;   /*!< Patterns for which to continue playing dialtone */
   char *registrar;        /*!< Registrar -- make sure you malloc this, as the registrar may have to survive module unloads */
   int refcount;                   /*!< each module that would have created this context should inc/dec this as appropriate */
   AST_LIST_HEAD_NOLOCK(, ast_sw) alts;   /*!< Alternative switches */
   ast_mutex_t macrolock;        /*!< A lock to implement "exclusive" macros - held whilst a call is executing in the macro */
   char name[0];           /*!< Name of the context */
};


/*! \brief ast_app: A registered application */
struct ast_app {
   int (*execute)(struct ast_channel *chan, void *data);
   const char *synopsis;         /*!< Synopsis text for 'show applications' */
   const char *description;      /*!< Description (help text) for 'show application &lt;name&gt;' */
   AST_RWLIST_ENTRY(ast_app) list;     /*!< Next app in list */
   struct ast_module *module;    /*!< Module this app belongs to */
   char name[0];           /*!< Name of the application */
};

/*! \brief ast_state_cb: An extension state notify register item */
struct ast_state_cb {
   int id;
   void *data;
   ast_state_cb_type callback;
   AST_LIST_ENTRY(ast_state_cb) entry;
};

/*! \brief Structure for dial plan hints

  \note Hints are pointers from an extension in the dialplan to one or
  more devices (tech/name) 
   - See \ref AstExtState
*/
struct ast_hint {
   struct ast_exten *exten;   /*!< Extension */
   int laststate;          /*!< Last known state */
   AST_LIST_HEAD_NOLOCK(, ast_state_cb) callbacks; /*!< Callback list for this extension */
   AST_RWLIST_ENTRY(ast_hint) list;/*!< Pointer to next hint in list */
};

static const struct cfextension_states {
   int extension_state;
   const char * const text;
} extension_states[] = {
   { AST_EXTENSION_NOT_INUSE,                     "Idle" },
   { AST_EXTENSION_INUSE,                         "InUse" },
   { AST_EXTENSION_BUSY,                          "Busy" },
   { AST_EXTENSION_UNAVAILABLE,                   "Unavailable" },
   { AST_EXTENSION_RINGING,                       "Ringing" },
   { AST_EXTENSION_INUSE | AST_EXTENSION_RINGING, "InUse&Ringing" },
   { AST_EXTENSION_ONHOLD,                        "Hold" },
   { AST_EXTENSION_INUSE | AST_EXTENSION_ONHOLD,  "InUse&Hold" }
};

struct statechange {
   AST_LIST_ENTRY(statechange) entry;
   char dev[0];
};

struct pbx_exception {
   AST_DECLARE_STRING_FIELDS(
      AST_STRING_FIELD(context); /*!< Context associated with this exception */
      AST_STRING_FIELD(exten);   /*!< Exten associated with this exception */
      AST_STRING_FIELD(reason);     /*!< The exception reason */
   );

   int priority;           /*!< Priority associated with this exception */
};

static int pbx_builtin_answer(struct ast_channel *, void *);
static int pbx_builtin_goto(struct ast_channel *, void *);
static int pbx_builtin_hangup(struct ast_channel *, void *);
static int pbx_builtin_background(struct ast_channel *, void *);
static int pbx_builtin_wait(struct ast_channel *, void *);
static int pbx_builtin_waitexten(struct ast_channel *, void *);
static int pbx_builtin_incomplete(struct ast_channel *, void *);
static int pbx_builtin_resetcdr(struct ast_channel *, void *);
static int pbx_builtin_setamaflags(struct ast_channel *, void *);
static int pbx_builtin_ringing(struct ast_channel *, void *);
static int pbx_builtin_proceeding(struct ast_channel *, void *);
static int pbx_builtin_progress(struct ast_channel *, void *);
static int pbx_builtin_congestion(struct ast_channel *, void *);
static int pbx_builtin_busy(struct ast_channel *, void *);
static int pbx_builtin_noop(struct ast_channel *, void *);
static int pbx_builtin_gotoif(struct ast_channel *, void *);
static int pbx_builtin_gotoiftime(struct ast_channel *, void *);
static int pbx_builtin_execiftime(struct ast_channel *, void *);
static int pbx_builtin_saynumber(struct ast_channel *, void *);
static int pbx_builtin_saydigits(struct ast_channel *, void *);
static int pbx_builtin_saycharacters(struct ast_channel *, void *);
static int pbx_builtin_sayphonetic(struct ast_channel *, void *);
static int matchcid(const char *cidpattern, const char *callerid);
int pbx_builtin_setvar(struct ast_channel *, void *);
void log_match_char_tree(struct match_char *node, char *prefix); /* for use anywhere */
int pbx_builtin_setvar_multiple(struct ast_channel *, void *);
static int pbx_builtin_importvar(struct ast_channel *, void *);
static void set_ext_pri(struct ast_channel *c, const char *exten, int pri); 
static void new_find_extension(const char *str, struct scoreboard *score, struct match_char *tree, int length, int spec, const char *callerid, const char *label, enum ext_match_t action);
static struct match_char *already_in_tree(struct match_char *current, char *pat);
static struct match_char *add_exten_to_pattern_tree(struct ast_context *con, struct ast_exten *e1, int findonly);
static struct match_char *add_pattern_node(struct ast_context *con, struct match_char *current, char *pattern, int is_pattern, int already, int specificity, struct match_char **parent);
static void create_match_char_tree(struct ast_context *con);
static struct ast_exten *get_canmatch_exten(struct match_char *node);
static void destroy_pattern_tree(struct match_char *pattern_tree);
int ast_hashtab_compare_contexts(const void *ah_a, const void *ah_b);
static int hashtab_compare_extens(const void *ha_a, const void *ah_b);
static int hashtab_compare_exten_numbers(const void *ah_a, const void *ah_b);
static int hashtab_compare_exten_labels(const void *ah_a, const void *ah_b);
unsigned int ast_hashtab_hash_contexts(const void *obj);
static unsigned int hashtab_hash_extens(const void *obj);
static unsigned int hashtab_hash_priority(const void *obj);
static unsigned int hashtab_hash_labels(const void *obj);
static void __ast_internal_context_destroy( struct ast_context *con);
static int ast_add_extension_nolock(const char *context, int replace, const char *extension,
   int priority, const char *label, const char *callerid,
   const char *application, void *data, void (*datad)(void *), const char *registrar);
static int add_pri_lockopt(struct ast_context *con, struct ast_exten *tmp,
   struct ast_exten *el, struct ast_exten *e, int replace, int lockhints);
static int ast_add_extension2_lockopt(struct ast_context *con,
   int replace, const char *extension, int priority, const char *label, const char *callerid,
   const char *application, void *data, void (*datad)(void *),
   const char *registrar, int lockconts, int lockhints);

/* a func for qsort to use to sort a char array */
static int compare_char(const void *a, const void *b)
{
   const char *ac = a;
   const char *bc = b;
   if ((*ac) < (*bc))
      return -1;
   else if ((*ac) == (*bc))
      return 0;
   else
      return 1;
}

/* labels, contexts are case sensitive  priority numbers are ints */
int ast_hashtab_compare_contexts(const void *ah_a, const void *ah_b)
{
   const struct ast_context *ac = ah_a;
   const struct ast_context *bc = ah_b;
   if (!ac || !bc) /* safety valve, but it might prevent a crash you'd rather have happen */
      return 1;
   /* assume context names are registered in a string table! */
   return strcmp(ac->name, bc->name);
}

static int hashtab_compare_extens(const void *ah_a, const void *ah_b)
{
   const struct ast_exten *ac = ah_a;
   const struct ast_exten *bc = ah_b;
   int x = strcmp(ac->exten, bc->exten);
   if (x) { /* if exten names are diff, then return */
      return x;
   }
   
   /* but if they are the same, do the cidmatch values match? */
   if (ac->matchcid && bc->matchcid) {
      return strcmp(ac->cidmatch,bc->cidmatch);
   } else if (!ac->matchcid && !bc->matchcid) {
      return 0; /* if there's no matchcid on either side, then this is a match */
   } else {
      return 1; /* if there's matchcid on one but not the other, they are different */
   }
}

static int hashtab_compare_exten_numbers(const void *ah_a, const void *ah_b)
{
   const struct ast_exten *ac = ah_a;
   const struct ast_exten *bc = ah_b;
   return ac->priority != bc->priority;
}

static int hashtab_compare_exten_labels(const void *ah_a, const void *ah_b)
{
   const struct ast_exten *ac = ah_a;
   const struct ast_exten *bc = ah_b;
   return strcmp(S_OR(ac->label, ""), S_OR(bc->label, ""));
}

unsigned int ast_hashtab_hash_contexts(const void *obj)
{
   const struct ast_context *ac = obj;
   return ast_hashtab_hash_string(ac->name);
}

static unsigned int hashtab_hash_extens(const void *obj)
{
   const struct ast_exten *ac = obj;
   unsigned int x = ast_hashtab_hash_string(ac->exten);
   unsigned int y = 0;
   if (ac->matchcid)
      y = ast_hashtab_hash_string(ac->cidmatch);
   return x+y;
}

static unsigned int hashtab_hash_priority(const void *obj)
{
   const struct ast_exten *ac = obj;
   return ast_hashtab_hash_int(ac->priority);
}

static unsigned int hashtab_hash_labels(const void *obj)
{
   const struct ast_exten *ac = obj;
   return ast_hashtab_hash_string(S_OR(ac->label, ""));
}


AST_RWLOCK_DEFINE_STATIC(globalslock);
static struct varshead globals = AST_LIST_HEAD_NOLOCK_INIT_VALUE;

static int autofallthrough = 1;
static int extenpatternmatchnew = 0;
static char *overrideswitch = NULL;

/*! \brief Subscription for device state change events */
static struct ast_event_sub *device_state_sub;

AST_MUTEX_DEFINE_STATIC(maxcalllock);
static int countcalls;
static int totalcalls;

static AST_RWLIST_HEAD_STATIC(acf_root, ast_custom_function);

/*! \brief Declaration of builtin applications */
static struct pbx_builtin {
   char name[AST_MAX_APP];
   int (*execute)(struct ast_channel *chan, void *data);
   char *synopsis;
   char *description;
} builtins[] =
{
   /* These applications are built into the PBX core and do not
      need separate modules */

   { "Answer", pbx_builtin_answer,
   "Answer a channel if ringing",
   "  Answer([delay]): If the call has not been answered, this application will\n"
   "answer it. Otherwise, it has no effect on the call. If a delay is specified,\n"
   "Asterisk will wait this number of milliseconds before returning to\n"
   "the dialplan after answering the call.\n"
   },

   { "BackGround", pbx_builtin_background,
   "Play an audio file while waiting for digits of an extension to go to.",
   "  Background(filename1[&filename2...][,options[,langoverride][,context]]):\n"
   "This application will play the given list of files (do not put extension)\n"
   "while waiting for an extension to be dialed by the calling channel. To\n"
   "continue waiting for digits after this application has finished playing\n"
   "files, the WaitExten application should be used. The 'langoverride' option\n"
   "explicitly specifies which language to attempt to use for the requested sound\n"
   "files. If a 'context' is specified, this is the dialplan context that this\n"
   "application will use when exiting to a dialed extension."
   "  If one of the requested sound files does not exist, call processing will be\n"
   "terminated.\n"
   "  Options:\n"
   "    s - Causes the playback of the message to be skipped\n"
   "          if the channel is not in the 'up' state (i.e. it\n"
   "          hasn't been answered yet). If this happens, the\n"
   "          application will return immediately.\n"
   "    n - Don't answer the channel before playing the files.\n"
   "    m - Only break if a digit hit matches a one digit\n"
   "          extension in the destination context.\n"
   "This application sets the following channel variable upon completion:\n"
   " BACKGROUNDSTATUS    The status of the background attempt as a text string, one of\n"
   "               SUCCESS | FAILED\n"
   "See Also: Playback (application) -- Play sound file(s) to the channel,\n"
   "                                    that cannot be interrupted\n"
   },

   { "Busy", pbx_builtin_busy,
   "Indicate the Busy condition",
   "  Busy([timeout]): This application will indicate the busy condition to\n"
   "the calling channel. If the optional timeout is specified, the calling channel\n"
   "will be hung up after the specified number of seconds. Otherwise, this\n"
   "application will wait until the calling channel hangs up.\n"
   },

   { "Congestion", pbx_builtin_congestion,
   "Indicate the Congestion condition",
   "  Congestion([timeout]): This application will indicate the congestion\n"
   "condition to the calling channel. If the optional timeout is specified, the\n"
   "calling channel will be hung up after the specified number of seconds.\n"
   "Otherwise, this application will wait until the calling channel hangs up.\n"
   },

   { "ExecIfTime", pbx_builtin_execiftime,
   "Conditional application execution based on the current time",
   "  ExecIfTime(<times>,<weekdays>,<mdays>,<months>?appname[(appargs)]):\n"
   "This application will execute the specified dialplan application, with optional\n"
   "arguments, if the current time matches the given time specification.\n"
   },

   { "Goto", pbx_builtin_goto,
   "Jump to a particular priority, extension, or context",
   "  Goto([[context,]extension,]priority): This application will set the current\n"
   "context, extension, and priority in the channel structure. After it completes, the\n"
   "pbx engine will continue dialplan execution at the specified location.\n"
   "If no specific extension, or extension and context, are specified, then this\n"
   "application will just set the specified priority of the current extension.\n"
   "  At least a priority is required as an argument, or the goto will return a -1,\n"
   "and the channel and call will be terminated.\n"
   "  If the location that is put into the channel information is bogus, and asterisk cannot\n"
   "find that location in the dialplan,\n"
   "then the execution engine will try to find and execute the code in the 'i' (invalid)\n"
   "extension in the current context. If that does not exist, it will try to execute the\n"
   "'h' extension. If either or neither the 'h' or 'i' extensions have been defined, the\n"
   "channel is hung up, and the execution of instructions on the channel is terminated.\n"
   "What this means is that, for example, you specify a context that does not exist, then\n"
   "it will not be possible to find the 'h' or 'i' extensions, and the call will terminate!\n"
   },

   { "GotoIf", pbx_builtin_gotoif,
   "Conditional goto",
   "  GotoIf(condition?[labeliftrue]:[labeliffalse]): This application will set the current\n"
   "context, extension, and priority in the channel structure based on the evaluation of\n"
   "the given condition. After this application completes, the\n"
   "pbx engine will continue dialplan execution at the specified location in the dialplan.\n"
   "The channel will continue at\n"
   "'labeliftrue' if the condition is true, or 'labeliffalse' if the condition is\n"
   "false. The labels are specified with the same syntax as used within the Goto\n"
   "application.  If the label chosen by the condition is omitted, no jump is\n"
   "performed, and the execution passes to the next instruction.\n"
   "If the target location is bogus, and does not exist, the execution engine will try \n"
   "to find and execute the code in the 'i' (invalid)\n"
   "extension in the current context. If that does not exist, it will try to execute the\n"
   "'h' extension. If either or neither the 'h' or 'i' extensions have been defined, the\n"
   "channel is hung up, and the execution of instructions on the channel is terminated.\n"
   "Remember that this command can set the current context, and if the context specified\n"
   "does not exist, then it will not be able to find any 'h' or 'i' extensions there, and\n"
   "the channel and call will both be terminated!\n"
   },

   { "GotoIfTime", pbx_builtin_gotoiftime,
   "Conditional Goto based on the current time",
   "  GotoIfTime(<times>,<weekdays>,<mdays>,<months>?[labeliftrue]:[labeliffalse]):\n"
   "This application will set the context, extension, and priority in the channel structure\n"
   "based on the evaluation of the given time specification. After this application completes,\n"
   "the pbx engine will continue dialplan execution at the specified location in the dialplan.\n"
   "If the current time is within the given time specification, the channel will continue at\n"
   "'labeliftrue'. Otherwise the channel will continue at 'labeliffalse'. If the label chosen\n"
   "by the condition is omitted, no jump is performed, and execution passes to the next\n"
   "instruction. If the target jump location is bogus, the same actions would be taken as for\n"
   "Goto.\n"
   "Further information on the time specification can be found in examples\n"
   "illustrating how to do time-based context includes in the dialplan.\n"
   },

   { "ImportVar", pbx_builtin_importvar,
   "Import a variable from a channel into a new variable",
   "  ImportVar(newvar=channelname,variable): This application imports a variable\n"
   "from the specified channel (as opposed to the current one) and stores it as\n"
   "a variable in the current channel (the channel that is calling this\n"
   "application). Variables created by this application have the same inheritance\n"
   "properties as those created with the Set application. See the documentation for\n"
   "Set for more information.\n"
   },

   { "Hangup", pbx_builtin_hangup,
   "Hang up the calling channel",
   "  Hangup([causecode]): This application will hang up the calling channel.\n"
   "If a causecode is given the channel's hangup cause will be set to the given\n"
   "value.\n"
   },

   { "Incomplete", pbx_builtin_incomplete,
   "returns AST_PBX_INCOMPLETE value",
   "  Incomplete([n]): Signals the PBX routines that the previous matched extension\n"
   "is incomplete and that further input should be allowed before matching can\n"
   "be considered to be complete.  Can be used within a pattern match when\n"
   "certain criteria warrants a longer match.\n"
   "  If the 'n' option is specified, then Incomplete will not attempt to answer\n"
   "the channel first.  Note that most channel types need to be in Answer state\n"
   "in order to receive DTMF.\n"
   },

   { "NoOp", pbx_builtin_noop,
   "Do Nothing (No Operation)",
   "  NoOp(): This application does nothing. However, it is useful for debugging\n"
   "purposes. Any text that is provided as arguments to this application can be\n"
   "viewed at the Asterisk CLI. This method can be used to see the evaluations of\n"
   "variables or functions without having any effect. Alternatively, see the\n"
      "Verbose() application for finer grain control of output at custom verbose levels.\n"
   },
   
   { "Proceeding", pbx_builtin_proceeding,
   "Indicate proceeding",
   "  Proceeding(): This application will request that a proceeding message\n"
   "be provided to the calling channel.\n"
   },
   
   { "Progress", pbx_builtin_progress,
   "Indicate progress",
   "  Progress(): This application will request that in-band progress information\n"
   "be provided to the calling channel.\n"
   },

   { "RaiseException", pbx_builtin_raise_exception,
   "Handle an exceptional condition",
   "  RaiseException(<reason>): This application will jump to the \"e\" extension\n"
   "in the current context, setting the dialplan function EXCEPTION(). If the \"e\"\n"
   "extension does not exist, the call will hangup.\n"
   },

   { "ResetCDR", pbx_builtin_resetcdr,
   "Resets the Call Data Record",
   "  ResetCDR([options]):  This application causes the Call Data Record to be\n"
   "reset.\n"
   "  Options:\n"
   "    w -- Store the current CDR record before resetting it.\n"
   "    a -- Store any stacked records.\n"
   "    v -- Save CDR variables.\n"
   "    e -- Enable CDR only (negate effects of NoCDR).\n"
   },

   { "Ringing", pbx_builtin_ringing,
   "Indicate ringing tone",
   "  Ringing(): This application will request that the channel indicate a ringing\n"
   "tone to the user.\n"
   },

   { "SayAlpha", pbx_builtin_saycharacters,
   "Say Alpha",
   "  SayAlpha(string): This application will play the sounds that correspond to\n"
   "the letters of the given string.\n"
   },

   { "SayDigits", pbx_builtin_saydigits,
   "Say Digits",
   "  SayDigits(digits): This application will play the sounds that correspond\n"
   "to the digits of the given number. This will use the language that is currently\n"
   "set for the channel. See the LANGUAGE function for more information on setting\n"
   "the language for the channel.\n"
   },

   { "SayNumber", pbx_builtin_saynumber,
   "Say Number",
   "  SayNumber(digits[,gender]): This application will play the sounds that\n"
   "correspond to the given number. Optionally, a gender may be specified.\n"
   "This will use the language that is currently set for the channel. See the\n"
   "LANGUAGE function for more information on setting the language for the channel.\n"
   },

   { "SayPhonetic", pbx_builtin_sayphonetic,
   "Say Phonetic",
   "  SayPhonetic(string): This application will play the sounds from the phonetic\n"
   "alphabet that correspond to the letters in the given string.\n"
   },

   { "Set", pbx_builtin_setvar,
   "Set channel variable or function value",
   "  Set(name=value)\n"
   "This function can be used to set the value of channel variables or dialplan\n"
   "functions. When setting variables, if the variable name is prefixed with _,\n"
   "the variable will be inherited into channels created from the current\n"
   "channel. If the variable name is prefixed with __, the variable will be\n"
   "inherited into channels created from the current channel and all children\n"
   "channels.\n"
   "Compatibility note: If (and only if), in /etc/asterisk/asterisk.conf, you have a [compat]\n"
    "category, and you have app_set = 1.6 under that, then the behavior of this\n"
    "app changes, and does not strip surrounding quotes from the right hand side\n"
    "as it did previously in 1.4. The app_set = 1.6 is only inserted if 'make samples'\n"
   "is executed, or if users insert this by hand into the asterisk.conf file.\n"
   "/nThe advantages of not stripping out quoting, and not caring about the\n"
   "separator characters (comma and vertical bar) were sufficient to make these\n"
   "changes in 1.6. Confusion about how many backslashes would be needed to properly\n"
   "protect separators and quotes in various database access strings has been greatly\n"
   "reduced by these changes.\n"
   },

   { "MSet", pbx_builtin_setvar_multiple,
   "Set channel variable(s) or function value(s)",
   "  MSet(name1=value1,name2=value2,...)\n"
   "This function can be used to set the value of channel variables or dialplan\n"
   "functions. When setting variables, if the variable name is prefixed with _,\n"
   "the variable will be inherited into channels created from the current\n"
   "channel. If the variable name is prefixed with __, the variable will be\n"
   "inherited into channels created from the current channel and all children\n"
   "channels.\n\n"
   "MSet behaves in a similar fashion to the way Set worked in 1.2/1.4 and is thus\n"
   "prone to doing things that you may not expect. For example, it strips surrounding\n"
   "double-quotes from the right-hand side (value). If you need to put a separator\n"
        "character (comma or vert-bar), you will need to escape them by inserting a backslash\n"
   "before them. Avoid its use if possible.\n"
   },

   { "SetAMAFlags", pbx_builtin_setamaflags,
   "Set the AMA Flags",
   "  SetAMAFlags([flag]): This application will set the channel's AMA Flags for\n"
   "  billing purposes.\n"
   },

   { "Wait", pbx_builtin_wait,
   "Waits for some time",
   "  Wait(seconds): This application waits for a specified number of seconds.\n"
   "Then, dialplan execution will continue at the next priority.\n"
   "  Note that the seconds can be passed with fractions of a second. For example,\n"
   "'1.5' will ask the application to wait for 1.5 seconds.\n"
   },

   { "WaitExten", pbx_builtin_waitexten,
   "Waits for an extension to be entered",
   "  WaitExten([seconds][,options]): This application waits for the user to enter\n"
   "a new extension for a specified number of seconds.\n"
   "  Note that the seconds can be passed with fractions of a second. For example,\n"
   "'1.5' will ask the application to wait for 1.5 seconds.\n"
   "  Options:\n"
   "    m[(x)] - Provide music on hold to the caller while waiting for an extension.\n"
   "               Optionally, specify the class for music on hold within parenthesis.\n"
   "Warning: Attempting to use this application from within a Macro will not work as\n"
   "desired. The Read() application is recommended as an alternative to WaitExten when\n"
   "used from a macro\n"
   "See Also: Playback(application), Background(application).\n"
   },
};

static struct ast_context *contexts;
static struct ast_hashtab *contexts_table = NULL;

AST_RWLOCK_DEFINE_STATIC(conlock);     /*!< Lock for the ast_context list */

static AST_RWLIST_HEAD_STATIC(apps, ast_app);

static AST_RWLIST_HEAD_STATIC(switches, ast_switch);

static int stateid = 1;
/* WARNING:
   When holding this list's lock, do _not_ do anything that will cause conlock
   to be taken, unless you _already_ hold it. The ast_merge_contexts_and_delete
   function will take the locks in conlock/hints order, so any other
   paths that require both locks must also take them in that order.
*/
static AST_RWLIST_HEAD_STATIC(hints, ast_hint);

static AST_LIST_HEAD_NOLOCK_STATIC(statecbs, ast_state_cb);

#ifdef CONTEXT_DEBUG

/* these routines are provided for doing run-time checks
   on the extension structures, in case you are having
   problems, this routine might help you localize where
   the problem is occurring. It's kinda like a debug memory
   allocator's arena checker... It'll eat up your cpu cycles!
   but you'll see, if you call it in the right places,
   right where your problems began...
*/

/* you can break on the check_contexts_trouble()
routine in your debugger to stop at the moment
there's a problem */
void check_contexts_trouble(void);

void check_contexts_trouble(void)
{
   int x = 1;
   x = 2;
}

static struct ast_context *find_context_locked(const char *context);
static struct ast_context *find_context(const char *context);
int check_contexts(char *, int);

int check_contexts(char *file, int line )
{
   struct ast_hashtab_iter *t1;
   struct ast_context *c1, *c2;
   int found = 0;
   struct ast_exten *e1, *e2, *e3;
   struct ast_exten ex;
   
   /* try to find inconsistencies */
   /* is every context in the context table in the context list and vice-versa ? */
   
   if (!contexts_table) {
      ast_log(LOG_NOTICE,"Called from: %s:%d: No contexts_table!\n", file, line);
      usleep(500000);
   }

   t1 = ast_hashtab_start_traversal(contexts_table);
   while( (c1 = ast_hashtab_next(t1))) {
      for(c2=contexts;c2;c2=c2->next) {
         if (!strcmp(c1->name, c2->name)) {
            found = 1;
            break;
         }
      }
      if (!found) {
         ast_log(LOG_NOTICE,"Called from: %s:%d: Could not find the %s context in the linked list\n", file, line, c1->name);
         check_contexts_trouble();
      }
   }
   ast_hashtab_end_traversal(t1);
   for(c2=contexts;c2;c2=c2->next) {
      c1 = find_context_locked(c2->name);
      if (!c1) {
         ast_log(LOG_NOTICE,"Called from: %s:%d: Could not find the %s context in the hashtab\n", file, line, c2->name);
         check_contexts_trouble();
      } else
         ast_unlock_contexts();
   }

   /* loop thru all contexts, and verify the exten structure compares to the 
      hashtab structure */
   for(c2=contexts;c2;c2=c2->next) {
      c1 = find_context_locked(c2->name);
      if (c1)
      {

         ast_unlock_contexts();

         /* is every entry in the root list also in the root_table? */
         for(e1 = c1->root; e1; e1=e1->next)
         {
            char dummy_name[1024];
            ex.exten = dummy_name;
            ex.matchcid = e1->matchcid;
            ex.cidmatch = e1->cidmatch;
            ast_copy_string(dummy_name, e1->exten, sizeof(dummy_name));
            e2 = ast_hashtab_lookup(c1->root_table, &ex);
            if (!e2) {
               if (e1->matchcid) {
                  ast_log(LOG_NOTICE,"Called from: %s:%d: The %s context records the exten %s (CID match: %s) but it is not in its root_table\n", file, line, c2->name, dummy_name, e1->cidmatch );
               } else {
                  ast_log(LOG_NOTICE,"Called from: %s:%d: The %s context records the exten %s but it is not in its root_table\n", file, line, c2->name, dummy_name );
               }
               check_contexts_trouble();
            }
         }
         
         /* is every entry in the root_table also in the root list? */ 
         if (!c2->root_table) {
            if (c2->root) {
               ast_log(LOG_NOTICE,"Called from: %s:%d: No c2->root_table for context %s!\n", file, line, c2->name);
               usleep(500000);
            }
         } else {
            t1 = ast_hashtab_start_traversal(c2->root_table);
            while( (e2 = ast_hashtab_next(t1)) ) {
               for(e1=c2->root;e1;e1=e1->next) {
                  if (!strcmp(e1->exten, e2->exten)) {
                     found = 1;
                     break;
                  }
               }
               if (!found) {
                  ast_log(LOG_NOTICE,"Called from: %s:%d: The %s context records the exten %s but it is not in its root_table\n", file, line, c2->name, e2->exten);
                  check_contexts_trouble();
               }
               
            }
            ast_hashtab_end_traversal(t1);
         }
      }
      /* is every priority reflected in the peer_table at the head of the list? */
      
      /* is every entry in the root list also in the root_table? */
      /* are the per-extension peer_tables in the right place? */

      for(e1 = c2->root; e1; e1 = e1->next) {
         
         for(e2=e1;e2;e2=e2->peer) {
            ex.priority = e2->priority;
            if (e2 != e1 && e2->peer_table) {
               ast_log(LOG_NOTICE,"Called from: %s:%d: The %s context, %s exten, %d priority has a peer_table entry, and shouldn't!\n", file, line, c2->name, e1->exten, e2->priority );
               check_contexts_trouble();
            }
            
            if (e2 != e1 && e2->peer_label_table) {
               ast_log(LOG_NOTICE,"Called from: %s:%d: The %s context, %s exten, %d priority has a peer_label_table entry, and shouldn't!\n", file, line, c2->name, e1->exten, e2->priority );
               check_contexts_trouble();
            }
            
            if (e2 == e1 && !e2->peer_table){
               ast_log(LOG_NOTICE,"Called from: %s:%d: The %s context, %s exten, %d priority doesn't have a peer_table!\n", file, line, c2->name, e1->exten, e2->priority );
               check_contexts_trouble();
            }
            
            if (e2 == e1 && !e2->peer_label_table) {
               ast_log(LOG_NOTICE,"Called from: %s:%d: The %s context, %s exten, %d priority doesn't have a peer_label_table!\n", file, line, c2->name, e1->exten, e2->priority );
               check_contexts_trouble();
            }
            

            e3 = ast_hashtab_lookup(e1->peer_table, &ex);
            if (!e3) {
               ast_log(LOG_NOTICE,"Called from: %s:%d: The %s context, %s exten, %d priority is not reflected in the peer_table\n", file, line, c2->name, e1->exten, e2->priority );
               check_contexts_trouble();
            }
         }
         
         if (!e1->peer_table){
            ast_log(LOG_NOTICE,"Called from: %s:%d: No e1->peer_table!\n", file, line);
            usleep(500000);
         }
         
         /* is every entry in the peer_table also in the peer list? */ 
         t1 = ast_hashtab_start_traversal(e1->peer_table);
         while( (e2 = ast_hashtab_next(t1)) ) {
            for(e3=e1;e3;e3=e3->peer) {
               if (e3->priority == e2->priority) {
                  found = 1;
                  break;
               }
            }
            if (!found) {
               ast_log(LOG_NOTICE,"Called from: %s:%d: The %s context, %s exten, %d priority is not reflected in the peer list\n", file, line, c2->name, e1->exten, e2->priority );
               check_contexts_trouble();
            }
         }
         ast_hashtab_end_traversal(t1);
      }
   }
   return 0;
}
#endif

/*
   \note This function is special. It saves the stack so that no matter
   how many times it is called, it returns to the same place */
int pbx_exec(struct ast_channel *c,       /*!< Channel */
        struct ast_app *app,     /*!< Application */
        void *data)        /*!< Data for execution */
{
   int res;
   struct ast_module_user *u = NULL;
   const char *saved_c_appl;
   const char *saved_c_data;

   if (c->cdr && !ast_check_hangup(c))
      ast_cdr_setapp(c->cdr, app->name, data);

   /* save channel values */
   saved_c_appl= c->appl;
   saved_c_data= c->data;

   c->appl = app->name;
   c->data = data;
   if (app->module)
      u = __ast_module_user_add(app->module, c);
   if (strcasecmp(app->name, "system") && !ast_strlen_zero(data) &&
         strchr(data, '|') && !strchr(data, ',')) {
      ast_log(LOG_WARNING, "The application delimiter is now the comma, not "
         "the pipe.  Did you forget to convert your dialplan?  (%s(%s))\n",
         app->name, (char *) data);
   }
   res = app->execute(c, S_OR(data, ""));
   if (app->module && u)
      __ast_module_user_remove(app->module, u);
   /* restore channel values */
   c->appl = saved_c_appl;
   c->data = saved_c_data;
   return res;
}


/*! Go no deeper than this through includes (not counting loops) */
#define AST_PBX_MAX_STACK  128

/*! \brief Find application handle in linked list
 */
struct ast_app *pbx_findapp(const char *app)
{
   struct ast_app *tmp;

   AST_RWLIST_RDLOCK(&apps);
   AST_RWLIST_TRAVERSE(&apps, tmp, list) {
      if (!strcasecmp(tmp->name, app))
         break;
   }
   AST_RWLIST_UNLOCK(&apps);

   return tmp;
}

static struct ast_switch *pbx_findswitch(const char *sw)
{
   struct ast_switch *asw;

   AST_RWLIST_RDLOCK(&switches);
   AST_RWLIST_TRAVERSE(&switches, asw, list) {
      if (!strcasecmp(asw->name, sw))
         break;
   }
   AST_RWLIST_UNLOCK(&switches);

   return asw;
}

static inline int include_valid(struct ast_include *i)
{
   if (!i->hastime)
      return 1;

   return ast_check_timing(&(i->timing));
}

static void pbx_destroy(struct ast_pbx *p)
{
   ast_free(p);
}

/* form a tree that fully describes all the patterns in a context's extensions 
 * in this tree, a "node" represents an individual character or character set
 * meant to match the corresponding character in a dial string. The tree 
 * consists of a series of match_char structs linked in a chain
 * via the alt_char pointers. More than one pattern can share the same parts of the 
 * tree as other extensions with the same pattern to that point. 
 * My first attempt to duplicate the finding of the 'best' pattern was flawed in that
 * I misunderstood the general algorithm. I thought that the 'best' pattern
 * was the one with lowest total score. This was not true. Thus, if you have
 * patterns "1XXXXX" and "X11111", you would be tempted to say that "X11111" is
 * the "best" match because it has fewer X's, and is therefore more specific, 
 * but this is not how the old algorithm works. It sorts matching patterns
 * in a similar collating sequence as sorting alphabetic strings, from left to 
 * right. Thus, "1XXXXX" comes before "X11111", and would be the "better" match,
 * because "1" is more specific than "X".
 * So, to accomodate this philosophy, I sort the tree branches along the alt_char
 * line so they are lowest to highest in specificity numbers. This way, as soon
 * as we encounter our first complete match, we automatically have the "best" 
 * match and can stop the traversal immediately. Same for CANMATCH/MATCHMORE.
 * If anyone would like to resurrect the "wrong" pattern trie searching algorithm,
 * they are welcome to revert pbx to before 1 Apr 2008.
 * As an example, consider these 4 extensions:
 * (a) NXXNXXXXXX
 * (b) 307754XXXX 
 * (c) fax
 * (d) NXXXXXXXXX
 *
 * In the above, between (a) and (d), (a) is a more specific pattern than (d), and would win over
 * most numbers. For all numbers beginning with 307754, (b) should always win.
 *
 * These pattern should form a (sorted) tree that looks like this:
 *   { "3" }  --next-->  { "0" }  --next--> { "7" } --next--> { "7" } --next--> { "5" } ... blah ... --> { "X" exten_match: (b) }
 *      |
 *      |alt
 *      |
 *   { "f" }  --next-->  { "a" }  --next--> { "x"  exten_match: (c) }
 *   { "N" }  --next-->  { "X" }  --next--> { "X" } --next--> { "N" } --next--> { "X" } ... blah ... --> { "X" exten_match: (a) }
 *      |                                                        |
 *      |                                                        |alt
 *      |alt                                                     |
 *      |                                                     { "X" } --next--> { "X" } ... blah ... --> { "X" exten_match: (d) }
 *      |
 *     NULL
 *
 *   In the above, I could easily turn "N" into "23456789", but I think that a quick "if( *z >= '2' && *z <= '9' )" might take
 *   fewer CPU cycles than a call to strchr("23456789",*z), where *z is the char to match...
 *
 *   traversal is pretty simple: one routine merely traverses the alt list, and for each matching char in the pattern,  it calls itself
 *   on the corresponding next pointer, incrementing also the pointer of the string to be matched, and passing the total specificity and length.
 *   We pass a pointer to a scoreboard down through, also.
 *   The scoreboard isn't as necessary to the revised algorithm, but I kept it as a handy way to return the matched extension.
 *   The first complete match ends the traversal, which should make this version of the pattern matcher faster
 *   the previous. The same goes for "CANMATCH" or "MATCHMORE"; the first such match ends the traversal. In both
 *   these cases, the reason we can stop immediately, is because the first pattern match found will be the "best"
 *   according to the sort criteria.
 *   Hope the limit on stack depth won't be a problem... this routine should 
 *   be pretty lean as far a stack usage goes. Any non-match terminates the recursion down a branch.
 *
 *   In the above example, with the number "3077549999" as the pattern, the traversor could match extensions a, b and d.  All are
 *   of length 10; they have total specificities of  24580, 10246, and 25090, respectively, not that this matters
 *   at all. (b) wins purely because the first character "3" is much more specific (lower specificity) than "N". I have
 *   left the specificity totals in the code as an artifact; at some point, I will strip it out.
 *
 *   Just how much time this algorithm might save over a plain linear traversal over all possible patterns is unknown,
 *   because it's a function of how many extensions are stored in a context. With thousands of extensions, the speedup
 *   can be very noticeable. The new matching algorithm can run several hundreds of times faster, if not a thousand or
 *   more times faster in extreme cases.
 *
 *   MatchCID patterns are also supported, and stored in the tree just as the extension pattern is. Thus, you
 *   can have patterns in your CID field as well.
 *
 * */


static void update_scoreboard(struct scoreboard *board, int length, int spec, struct ast_exten *exten, char last, const char *callerid, int deleted, struct match_char *node)
{
   /* if this extension is marked as deleted, then skip this -- if it never shows
      on the scoreboard, it will never be found, nor will halt the traversal. */
   if (deleted)
      return;
   board->total_specificity = spec;
   board->total_length = length;
   board->exten = exten;
   board->last_char = last;
   board->node = node;
#ifdef NEED_DEBUG_HERE
   ast_log(LOG_NOTICE,"Scoreboarding (LONGER) %s, len=%d, score=%d\n", exten->exten, length, spec);
#endif
}

void log_match_char_tree(struct match_char *node, char *prefix)
{
   char extenstr[40];
   struct ast_str *my_prefix = ast_str_alloca(1024); 

   extenstr[0] = '\0';

   if (node && node->exten && node->exten)
      snprintf(extenstr, sizeof(extenstr), "(%p)", node->exten);
   
   if (strlen(node->x) > 1) {
      ast_debug(1, "%s[%s]:%c:%c:%d:%s%s%s\n", prefix, node->x, node->is_pattern ? 'Y':'N', 
         node->deleted? 'D':'-', node->specificity, node->exten? "EXTEN:":"", 
         node->exten ? node->exten->exten : "", extenstr);
   } else {
      ast_debug(1, "%s%s:%c:%c:%d:%s%s%s\n", prefix, node->x, node->is_pattern ? 'Y':'N', 
         node->deleted? 'D':'-', node->specificity, node->exten? "EXTEN:":"", 
         node->exten ? node->exten->exten : "", extenstr);
   }

   ast_str_set(&my_prefix, 0, "%s+       ", prefix);

   if (node->next_char)
      log_match_char_tree(node->next_char, my_prefix->str);

   if (node->alt_char)
      log_match_char_tree(node->alt_char, prefix);
}

static void cli_match_char_tree(struct match_char *node, char *prefix, int fd)
{
   char extenstr[40];
   struct ast_str *my_prefix = ast_str_alloca(1024);
   
   extenstr[0] = '\0';

   if (node && node->exten && node->exten)
      snprintf(extenstr, sizeof(extenstr), "(%p)", node->exten);
   
   if (strlen(node->x) > 1) {
      ast_cli(fd, "%s[%s]:%c:%c:%d:%s%s%s\n", prefix, node->x, node->is_pattern ? 'Y' : 'N', 
         node->deleted ? 'D' : '-', node->specificity, node->exten? "EXTEN:" : "", 
         node->exten ? node->exten->exten : "", extenstr);
   } else {
      ast_cli(fd, "%s%s:%c:%c:%d:%s%s%s\n", prefix, node->x, node->is_pattern ? 'Y' : 'N', 
         node->deleted ? 'D' : '-', node->specificity, node->exten? "EXTEN:" : "", 
         node->exten ? node->exten->exten : "", extenstr);
   }

   ast_str_set(&my_prefix, 0, "%s+       ", prefix);

   if (node->next_char)
      cli_match_char_tree(node->next_char, my_prefix->str, fd);

   if (node->alt_char)
      cli_match_char_tree(node->alt_char, prefix, fd);
}

static struct ast_exten *get_canmatch_exten(struct match_char *node)
{
   /* find the exten at the end of the rope */
   struct match_char *node2 = node;

   for (node2 = node; node2; node2 = node2->next_char) {
      if (node2->exten) {
#ifdef NEED_DEBUG_HERE
         ast_log(LOG_NOTICE,"CanMatch_exten returns exten %s(%p)\n", node2->exten->exten, node2->exten);
#endif
         return node2->exten;
      }
   }
#ifdef NEED_DEBUG_HERE
   ast_log(LOG_NOTICE,"CanMatch_exten returns NULL, match_char=%s\n", node->x);
#endif
   return 0;
}

static struct ast_exten *trie_find_next_match(struct match_char *node)
{
   struct match_char *m3;
   struct match_char *m4;
   struct ast_exten *e3;
   
   if (node && node->x[0] == '.' && !node->x[1]) /* dot and ! will ALWAYS be next match in a matchmore */
      return node->exten;
   
   if (node && node->x[0] == '!' && !node->x[1])
      return node->exten;
   
   if (!node || !node->next_char)
      return NULL;
   
   m3 = node->next_char;

   if (m3->exten)
      return m3->exten;
   for(m4=m3->alt_char; m4; m4 = m4->alt_char) {
      if (m4->exten)
         return m4->exten;
   }
   for(m4=m3; m4; m4 = m4->alt_char) {
      e3 = trie_find_next_match(m3);
      if (e3)
         return e3;
   }
   return NULL;
}

#ifdef DEBUG_THIS
static char *action2str(enum ext_match_t action)
{
   switch(action)
   {
   case E_MATCH:
      return "MATCH";
   case E_CANMATCH:
      return "CANMATCH";
   case E_MATCHMORE:
      return "MATCHMORE";
   case E_FINDLABEL:
      return "FINDLABEL";
   case E_SPAWN:
      return "SPAWN";
   default:
      return "?ACTION?";
   }
}

#endif

static void new_find_extension(const char *str, struct scoreboard *score, struct match_char *tree, int length, int spec, const char *callerid, const char *label, enum ext_match_t action)
{
   struct match_char *p; /* note minimal stack storage requirements */
   struct ast_exten pattern = { .label = label };
#ifdef DEBUG_THIS
   if (tree)
      ast_log(LOG_NOTICE,"new_find_extension called with %s on (sub)tree %s action=%s\n", str, tree->x, action2str(action));
   else
      ast_log(LOG_NOTICE,"new_find_extension called with %s on (sub)tree NULL action=%s\n", str, action2str(action));
#endif
   for (p=tree; p; p=p->alt_char) {
      if (p->x[0] == 'N') {
         if (p->x[1] == 0 && *str >= '2' && *str <= '9' ) {
#define NEW_MATCHER_CHK_MATCH        \
            if (p->exten && !(*(str+1))) { /* if a shorter pattern matches along the way, might as well report it */             \
               if (action == E_MATCH || action == E_SPAWN || action == E_FINDLABEL) { /* if in CANMATCH/MATCHMORE, don't let matches get in the way */   \
                  update_scoreboard(score, length+1, spec+p->specificity, p->exten,0,callerid, p->deleted, p);                 \
                  if (!p->deleted) {                                                                                           \
                     if (action == E_FINDLABEL) {                                                                             \
                        if (ast_hashtab_lookup(score->exten->peer_label_table, &pattern)) {                                  \
                           ast_debug(4, "Found label in preferred extension\n");                                            \
                           return;                                                                                          \
                        }                                                                                                    \
                     } else {                                                                                                 \
                        ast_debug(4,"returning an exact match-- first found-- %s\n", p->exten->exten);                       \
                        return; /* the first match, by definition, will be the best, because of the sorted tree */           \
                     }                                                                                                        \
                  }                                                                                                            \
               }                                                                                                                \
            }
            
#define NEW_MATCHER_RECURSE              \
            if (p->next_char && ( *(str+1) || (p->next_char->x[0] == '/' && p->next_char->x[1] == 0)                 \
                                               || p->next_char->x[0] == '!')) {                                          \
               if (*(str+1) || p->next_char->x[0] == '!') {                                                         \
                  new_find_extension(str+1, score, p->next_char, length+1, spec+p->specificity, callerid, label, action); \
                  if (score->exten)  {                                                                             \
                       ast_debug(4,"returning an exact match-- %s\n", score->exten->exten);                         \
                     return; /* the first match is all we need */                                                 \
                  }                                                                                    \
               } else {                                                                                             \
                  new_find_extension("/", score, p->next_char, length+1, spec+p->specificity, callerid, label, action);  \
                  if (score->exten || ((action == E_CANMATCH || action == E_MATCHMORE) && score->canmatch)) {      \
                       ast_debug(4,"returning a (can/more) match--- %s\n", score->exten ? score->exten->exten :     \
                                       "NULL");                                                                        \
                     return; /* the first match is all we need */                                                 \
                  }                                                                                    \
               }                                                                                                    \
            } else if (p->next_char && !*(str+1)) {                                                                  \
               score->canmatch = 1;                                                                                 \
               score->canmatch_exten = get_canmatch_exten(p);                                                       \
               if (action == E_CANMATCH || action == E_MATCHMORE) {                                                 \
                    ast_debug(4,"returning a canmatch/matchmore--- str=%s\n", str);                                  \
                  return;                                                                                          \
               }                                                                                        \
            }
            
            NEW_MATCHER_CHK_MATCH;
            NEW_MATCHER_RECURSE;
         }
      } else if (p->x[0] == 'Z') {
         if (p->x[1] == 0 && *str >= '1' && *str <= '9' ) {
            NEW_MATCHER_CHK_MATCH;
            NEW_MATCHER_RECURSE;
         }
      } else if (p->x[0] == 'X') { 
         if (p->x[1] == 0 && *str >= '0' && *str <= '9' ) {
            NEW_MATCHER_CHK_MATCH;
            NEW_MATCHER_RECURSE;
         }
      } else if (p->x[0] == '.' && p->x[1] == 0) {
         /* how many chars will the . match against? */
         int i = 0;
         const char *str2 = str;
         while (*str2 && *str2 != '/') {
            str2++;
            i++;
         }
         if (p->exten && *str2 != '/') {
            update_scoreboard(score, length+i, spec+(i*p->specificity), p->exten, '.', callerid, p->deleted, p);
            if (score->exten) {
               ast_debug(4,"return because scoreboard has a match with '/'--- %s\n", score->exten->exten);
               return; /* the first match is all we need */
            }
         }
         if (p->next_char && p->next_char->x[0] == '/' && p->next_char->x[1] == 0) {
            new_find_extension("/", score, p->next_char, length+i, spec+(p->specificity*i), callerid, label, action);
            if (score->exten || ((action == E_CANMATCH || action == E_MATCHMORE) && score->canmatch)) {
               ast_debug(4,"return because scoreboard has exact match OR CANMATCH/MATCHMORE & canmatch set--- %s\n", score->exten ? score->exten->exten : "NULL");
               return; /* the first match is all we need */
            }
         }
      } else if (p->x[0] == '!' && p->x[1] == 0) {
         /* how many chars will the . match against? */
         int i = 1;
         const char *str2 = str;
         while (*str2 && *str2 != '/') {
            str2++;
            i++;
         }
         if (p->exten && *str2 != '/') {
            update_scoreboard(score, length+1, spec+(p->specificity*i), p->exten, '!', callerid, p->deleted, p);
            if (score->exten) {
               ast_debug(4,"return because scoreboard has a '!' match--- %s\n", score->exten->exten);
               return; /* the first match is all we need */
            }
         }
         if (p->next_char && p->next_char->x[0] == '/' && p->next_char->x[1] == 0) {
            new_find_extension("/", score, p->next_char, length+i, spec+(p->specificity*i), callerid, label, action);
            if (score->exten || ((action == E_CANMATCH || action == E_MATCHMORE) && score->canmatch)) {
               ast_debug(4,"return because scoreboard has exact match OR CANMATCH/MATCHMORE & canmatch set with '/' and '!'--- %s\n", score->exten ? score->exten->exten : "NULL");
               return; /* the first match is all we need */
            }
         }
      } else if (p->x[0] == '/' && p->x[1] == 0) {
         /* the pattern in the tree includes the cid match! */
         if (p->next_char && callerid && *callerid) {
            new_find_extension(callerid, score, p->next_char, length+1, spec, callerid, label, action);
            if (score->exten || ((action == E_CANMATCH || action == E_MATCHMORE) && score->canmatch)) {
               ast_debug(4,"return because scoreboard has exact match OR CANMATCH/MATCHMORE & canmatch set with '/'--- %s\n", score->exten ? score->exten->exten : "NULL");
               return; /* the first match is all we need */
            }
         }
      } else if (strchr(p->x, *str)) {
         ast_debug(4, "Nothing strange about this match\n");
         NEW_MATCHER_CHK_MATCH;
         NEW_MATCHER_RECURSE;
      }
   }
   ast_debug(4,"return at end of func\n");
}

/* the algorithm for forming the extension pattern tree is also a bit simple; you 
 * traverse all the extensions in a context, and for each char of the extension,
 * you see if it exists in the tree; if it doesn't, you add it at the appropriate
 * spot. What more can I say? At the end of each exten, you cap it off by adding the
 * address of the extension involved. Duplicate patterns will be complained about.
 *
 * Ideally, this would be done for each context after it is created and fully 
 * filled. It could be done as a finishing step after extensions.conf or .ael is
 * loaded, or it could be done when the first search is encountered. It should only
 * have to be done once, until the next unload or reload.
 *
 * I guess forming this pattern tree would be analogous to compiling a regex. Except
 * that a regex only handles 1 pattern, really. This trie holds any number
 * of patterns. Well, really, it **could** be considered a single pattern,
 * where the "|" (or) operator is allowed, I guess, in a way, sort of...
 */

static struct match_char *already_in_tree(struct match_char *current, char *pat)
{
   struct match_char *t;

   if (!current)
      return 0;

   for (t = current; t; t = t->alt_char) {
      if (!strcmp(pat, t->x)) /* uh, we may want to sort exploded [] contents to make matching easy */
         return t;
   }

   return 0;
}

/* The first arg is the location of the tree ptr, or the 
   address of the next_char ptr in the node, so we can mess
   with it, if we need to insert at the beginning of the list */

static void insert_in_next_chars_alt_char_list(struct match_char **parent_ptr, struct match_char *node)
{
   struct match_char *curr, *lcurr;
   
   /* insert node into the tree at "current", so the alt_char list from current is
      sorted in increasing value as you go to the leaves */
   if (!(*parent_ptr)) {
      *parent_ptr = node;
   } else {
      if ((*parent_ptr)->specificity > node->specificity){
         /* insert at head */
         node->alt_char = (*parent_ptr);
         *parent_ptr = node;
      } else {
         lcurr = *parent_ptr;
         for (curr=(*parent_ptr)->alt_char; curr; curr = curr->alt_char) {
            if (curr->specificity > node->specificity) {
               node->alt_char = curr;
               lcurr->alt_char = node;
               break;
            }
            lcurr = curr;
         }
         if (!curr)
         {
            lcurr->alt_char = node;
         }
      }
   }
}



static struct match_char *add_pattern_node(struct ast_context *con, struct match_char *current, char *pattern, int is_pattern, int already, int specificity, struct match_char **nextcharptr)
{
   struct match_char *m;
   
   if (!(m = ast_calloc(1, sizeof(*m))))
      return NULL;

   if (!(m->x = ast_strdup(pattern))) {
      ast_free(m);
      return NULL;
   }

   /* the specificity scores are the same as used in the old
      pattern matcher. */
   m->is_pattern = is_pattern;
   if (specificity == 1 && is_pattern && pattern[0] == 'N')
      m->specificity = 0x0802;
   else if (specificity == 1 && is_pattern && pattern[0] == 'Z')
      m->specificity = 0x0901;
   else if (specificity == 1 && is_pattern && pattern[0] == 'X')
      m->specificity = 0x0a00;
   else if (specificity == 1 && is_pattern && pattern[0] == '.')
      m->specificity = 0x10000;
   else if (specificity == 1 && is_pattern && pattern[0] == '!')
      m->specificity = 0x20000;
   else
      m->specificity = specificity;
   
   if (!con->pattern_tree) {
      insert_in_next_chars_alt_char_list(&con->pattern_tree, m);
   } else {
      if (already) { /* switch to the new regime (traversing vs appending)*/
         insert_in_next_chars_alt_char_list(nextcharptr, m);
      } else {
         insert_in_next_chars_alt_char_list(&current->next_char, m);
      }
   }

   return m;
}

static struct match_char *add_exten_to_pattern_tree(struct ast_context *con, struct ast_exten *e1, int findonly)
{
   struct match_char *m1 = NULL, *m2 = NULL, **m0;
   int specif;
   int already;
   int pattern = 0;
   char buf[256];
   char extenbuf[512];
   char *s1 = extenbuf;
   int l1 = strlen(e1->exten) + strlen(e1->cidmatch) + 2;
   

   ast_copy_string(extenbuf, e1->exten, sizeof(extenbuf));

   if (e1->matchcid &&  l1 <= sizeof(extenbuf)) {
      strcat(extenbuf,"/");
      strcat(extenbuf,e1->cidmatch);
   } else if (l1 > sizeof(extenbuf)) {
      ast_log(LOG_ERROR,"The pattern %s/%s is too big to deal with: it will be ignored! Disaster!\n", e1->exten, e1->cidmatch);
      return 0;
   }
#ifdef NEED_DEBUG
   ast_log(LOG_DEBUG,"Adding exten %s%c%s to tree\n", s1, e1->matchcid? '/':' ', e1->matchcid? e1->cidmatch : "");
#endif
   m1 = con->pattern_tree; /* each pattern starts over at the root of the pattern tree */
   m0 = &con->pattern_tree;
   already = 1;

   if ( *s1 == '_') {
      pattern = 1;
      s1++;
   }
   while( *s1 ) {
      if (pattern && *s1 == '[' && *(s1-1) != '\\') {
         char *s2 = buf;
         buf[0] = 0;
         s1++; /* get past the '[' */
         while (*s1 != ']' && *(s1-1) != '\\' ) {
            if (*s1 == '\\') {
               if (*(s1+1) == ']') {
                  *s2++ = ']';
                  s1++;s1++;
               } else if (*(s1+1) == '\\') {
                  *s2++ = '\\';
                  s1++;s1++;
               } else if (*(s1+1) == '-') {
                  *s2++ = '-';
                  s1++; s1++;
               } else if (*(s1+1) == '[') {
                  *s2++ = '[';
                  s1++; s1++;
               }
            } else if (*s1 == '-') { /* remember to add some error checking to all this! */
               char s3 = *(s1-1);
               char s4 = *(s1+1);
               for (s3++; s3 <= s4; s3++) {
                  *s2++ = s3;
               }
               s1++; s1++;
            } else if (*s1 == '\0') {
               ast_log(LOG_WARNING, "A matching ']' was not found for '[' in pattern string '%s'\n", extenbuf);
               break;
            } else {
               *s2++ = *s1++;
            }
         }
         *s2 = 0; /* null terminate the exploded range */
         /* sort the characters */

         specif = strlen(buf);
         qsort(buf, specif, 1, compare_char);
         specif <<= 8;
         specif += buf[0];
      } else {
         
         if (*s1 == '\\') {
            s1++;
            buf[0] = *s1;
         } else {
            if (pattern) {
               if (*s1 == 'n') /* make sure n,x,z patterns are canonicalized to N,X,Z */
                  *s1 = 'N';
               else if (*s1 == 'x')
                  *s1 = 'X';
               else if (*s1 == 'z')
                  *s1 = 'Z';
            }
            buf[0] = *s1;
         }
         buf[1] = 0;
         specif = 1;
      }
      m2 = 0;
      if (already && (m2=already_in_tree(m1,buf)) && m2->next_char) {
         if (!(*(s1+1))) {  /* if this is the end of the pattern, but not the end of the tree, then mark this node with the exten...
                        a shorter pattern might win if the longer one doesn't match */
            m2->exten = e1;
            m2->deleted = 0;
         }
         m1 = m2->next_char; /* m1 points to the node to compare against */
         m0 = &m2->next_char; /* m0 points to the ptr that points to m1 */
      } else { /* not already OR not m2 OR nor m2->next_char */
         if (m2) {
            if (findonly)
               return m2;
            m1 = m2; /* while m0 stays the same */
         } else {
            if (findonly)
               return m1;
            m1 = add_pattern_node(con, m1, buf, pattern, already,specif, m0); /* m1 is the node just added */
            m0 = &m1->next_char;
         }
         
         if (!(*(s1+1))) {
            m1->deleted = 0;
            m1->exten = e1;
         }
         
         already = 0;
      }
      s1++; /* advance to next char */
   }
   return m1;
}

static void create_match_char_tree(struct ast_context *con)
{
   struct ast_hashtab_iter *t1;
   struct ast_exten *e1;
#ifdef NEED_DEBUG
   int biggest_bucket, resizes, numobjs, numbucks;
   
   ast_log(LOG_DEBUG,"Creating Extension Trie for context %s\n", con->name);
   ast_hashtab_get_stats(con->root_table, &biggest_bucket, &resizes, &numobjs, &numbucks);
   ast_log(LOG_DEBUG,"This tree has %d objects in %d bucket lists, longest list=%d objects, and has resized %d times\n",
         numobjs, numbucks, biggest_bucket, resizes);
#endif
   t1 = ast_hashtab_start_traversal(con->root_table);
   while( (e1 = ast_hashtab_next(t1)) ) {
      if (e1->exten)
         add_exten_to_pattern_tree(con, e1, 0);
      else
         ast_log(LOG_ERROR,"Attempt to create extension with no extension name.\n");
   }
   ast_hashtab_end_traversal(t1);
}

static void destroy_pattern_tree(struct match_char *pattern_tree) /* pattern tree is a simple binary tree, sort of, so the proper way to destroy it is... recursively! */
{
   /* destroy all the alternates */
   if (pattern_tree->alt_char) {
      destroy_pattern_tree(pattern_tree->alt_char);
      pattern_tree->alt_char = 0;
   }
   /* destroy all the nexts */
   if (pattern_tree->next_char) {
      destroy_pattern_tree(pattern_tree->next_char);
      pattern_tree->next_char = 0;
   }
   pattern_tree->exten = 0; /* never hurts to make sure there's no pointers laying around */
   if (pattern_tree->x)
      free(pattern_tree->x);
   free(pattern_tree);
}

/*
 * Special characters used in patterns:
 * '_'   underscore is the leading character of a pattern.
 *    In other position it is treated as a regular char.
 * .  one or more of any character. Only allowed at the end of
 *    a pattern.
 * !  zero or more of anything. Also impacts the result of CANMATCH
 *    and MATCHMORE. Only allowed at the end of a pattern.
 *    In the core routine, ! causes a match with a return code of 2.
 *    In turn, depending on the search mode: (XXX check if it is implemented)
 *    - E_MATCH retuns 1 (does match)
 *    - E_MATCHMORE returns 0 (no match)
 *    - E_CANMATCH returns 1 (does match)
 *
 * /  should not appear as it is considered the separator of the CID info.
 *    XXX at the moment we may stop on this char.
 *
 * X Z N match ranges 0-9, 1-9, 2-9 respectively.
 * [  denotes the start of a set of character. Everything inside
 *    is considered literally. We can have ranges a-d and individual
 *    characters. A '[' and '-' can be considered literally if they
 *    are just before ']'.
 *    XXX currently there is no way to specify ']' in a range, nor \ is
 *    considered specially.
 *
 * When we compare a pattern with a specific extension, all characters in the extension
 * itself are considered literally.
 * XXX do we want to consider space as a separator as well ?
 * XXX do we want to consider the separators in non-patterns as well ?
 */

/*!
 * \brief helper functions to sort extensions and patterns in the desired way,
 * so that more specific patterns appear first.
 *
 * ext_cmp1 compares individual characters (or sets of), returning
 * an int where bits 0-7 are the ASCII code of the first char in the set,
 * while bit 8-15 are the cardinality of the set minus 1.
 * This way more specific patterns (smaller cardinality) appear first.
 * Wildcards have a special value, so that we can directly compare them to
 * sets by subtracting the two values. In particular:
 *    0x000xx     one character, xx
 *    0x0yyxx     yy character set starting with xx
 *    0x10000     '.' (one or more of anything)
 *    0x20000     '!' (zero or more of anything)
 *    0x30000     NUL (end of string)
 *    0x40000     error in set.
 * The pointer to the string is advanced according to needs.
 * NOTES:
 * 1. the empty set is equivalent to NUL.
 * 2. given that a full set has always 0 as the first element,
 *    we could encode the special cases as 0xffXX where XX
 *    is 1, 2, 3, 4 as used above.
 */
static int ext_cmp1(const char **p)
{
   uint32_t chars[8];
   int c, cmin = 0xff, count = 0;
   const char *end;

   /* load, sign extend and advance pointer until we find
    * a valid character.
    */
   c = *(*p)++;

   /* always return unless we have a set of chars */
   switch (toupper(c)) {
   default: /* ordinary character */
      return 0x0000 | (c & 0xff);

   case 'N':   /* 2..9 */
      return 0x0800 | '2' ;

   case 'X':   /* 0..9 */
      return 0x0A00 | '0';

   case 'Z':   /* 1..9 */
      return 0x0900 | '1';

   case '.':   /* wildcard */
      return 0x10000;

   case '!':   /* earlymatch */
      return 0x20000;   /* less specific than NULL */

   case '\0':  /* empty string */
      *p = NULL;
      return 0x30000;

   case '[':   /* pattern */
      break;
   }
   /* locate end of set */
   end = strchr(*p, ']');  

   if (end == NULL) {
      ast_log(LOG_WARNING, "Wrong usage of [] in the extension\n");
      return 0x40000;   /* XXX make this entry go last... */
   }

   memset(chars, '\0', sizeof(chars)); /* clear all chars in the set */
   for (; *p < end  ; (*p)++) {
      unsigned char c1, c2;   /* first-last char in range */
      c1 = (unsigned char)((*p)[0]);
      if (*p + 2 < end && (*p)[1] == '-') { /* this is a range */
         c2 = (unsigned char)((*p)[2]);
         *p += 2; /* skip a total of 3 chars */
      } else         /* individual character */
         c2 = c1;
      if (c1 < cmin)
         cmin = c1;
      for (; c1 <= c2; c1++) {
         uint32_t mask = 1 << (c1 % 32);
         if ( (chars[ c1 / 32 ] & mask) == 0)
            count += 0x100;
         chars[ c1 / 32 ] |= mask;
      }
   }
   (*p)++;
   return count == 0 ? 0x30000 : (count | cmin);
}

/*!
 * \brief the full routine to compare extensions in rules.
 */
static int ext_cmp(const char *a, const char *b)
{
   /* make sure non-patterns come first.
    * If a is not a pattern, it either comes first or
    * we use strcmp to compare the strings.
    */
   int ret = 0;

   if (a[0] != '_')
      return (b[0] == '_') ? -1 : strcmp(a, b);

   /* Now we know a is a pattern; if b is not, a comes first */
   if (b[0] != '_')
      return 1;
#if 0 /* old mode for ext matching */
   return strcmp(a, b);
#endif
   /* ok we need full pattern sorting routine */
   while (!ret && a && b)
      ret = ext_cmp1(&a) - ext_cmp1(&b);
   if (ret == 0)
      return 0;
   else
      return (ret > 0) ? 1 : -1;
}

int ast_extension_cmp(const char *a, const char *b)
{
   return ext_cmp(a, b);
}

/*!
 * \internal
 * \brief used ast_extension_{match|close}
 * mode is as follows:
 * E_MATCH     success only on exact match
 * E_MATCHMORE success only on partial match (i.e. leftover digits in pattern)
 * E_CANMATCH  either of the above.
 * \retval 0 on no-match
 * \retval 1 on match
 * \retval 2 on early match.
 */

static int _extension_match_core(const char *pattern, const char *data, enum ext_match_t mode)
{
   mode &= E_MATCH_MASK;   /* only consider the relevant bits */
   
#ifdef NEED_DEBUG_HERE
   ast_log(LOG_NOTICE,"match core: pat: '%s', dat: '%s', mode=%d\n", pattern, data, (int)mode);
#endif
   
   if ( (mode == E_MATCH) && (pattern[0] == '_') && (!strcasecmp(pattern,data)) ) { /* note: if this test is left out, then _x. will not match _x. !!! */
#ifdef NEED_DEBUG_HERE
      ast_log(LOG_NOTICE,"return (1) - pattern matches pattern\n");
#endif
      return 1;
   }

   if (pattern[0] != '_') { /* not a pattern, try exact or partial match */
      int ld = strlen(data), lp = strlen(pattern);
      
      if (lp < ld) {    /* pattern too short, cannot match */
#ifdef NEED_DEBUG_HERE
         ast_log(LOG_NOTICE,"return (0) - pattern too short, cannot match\n");
#endif
         return 0;
      }
      /* depending on the mode, accept full or partial match or both */
      if (mode == E_MATCH) {
#ifdef NEED_DEBUG_HERE
         ast_log(LOG_NOTICE,"return (!strcmp(%s,%s) when mode== E_MATCH)\n", pattern, data);
#endif
         return !strcmp(pattern, data); /* 1 on match, 0 on fail */
      } 
      if (ld == 0 || !strncasecmp(pattern, data, ld)) { /* partial or full match */
#ifdef NEED_DEBUG_HERE
         ast_log(LOG_NOTICE,"return (mode(%d) == E_MATCHMORE ? lp(%d) > ld(%d) : 1)\n", mode, lp, ld);
#endif
         return (mode == E_MATCHMORE) ? lp > ld : 1; /* XXX should consider '!' and '/' ? */
      } else {
#ifdef NEED_DEBUG_HERE
         ast_log(LOG_NOTICE,"return (0) when ld(%d) > 0 && pattern(%s) != data(%s)\n", ld, pattern, data);
#endif
         return 0;
      }
   }
   pattern++; /* skip leading _ */
   /*
    * XXX below we stop at '/' which is a separator for the CID info. However we should
    * not store '/' in the pattern at all. When we insure it, we can remove the checks.
    */
   while (*data && *pattern && *pattern != '/') {
      const char *end;

      if (*data == '-') { /* skip '-' in data (just a separator) */
         data++;
         continue;
      }
      switch (toupper(*pattern)) {
      case '[':   /* a range */
         end = strchr(pattern+1, ']'); /* XXX should deal with escapes ? */
         if (end == NULL) {
            ast_log(LOG_WARNING, "Wrong usage of [] in the extension\n");
            return 0;   /* unconditional failure */
         }
         for (pattern++; pattern != end; pattern++) {
            if (pattern+2 < end && pattern[1] == '-') { /* this is a range */
               if (*data >= pattern[0] && *data <= pattern[2])
                  break;   /* match found */
               else {
                  pattern += 2; /* skip a total of 3 chars */
                  continue;
               }
            } else if (*data == pattern[0])
               break;   /* match found */
         }
         if (pattern == end) {
#ifdef NEED_DEBUG_HERE
            ast_log(LOG_NOTICE,"return (0) when pattern==end\n");
#endif
            return 0;
         }
         pattern = end; /* skip and continue */
         break;
      case 'N':
         if (*data < '2' || *data > '9') {
#ifdef NEED_DEBUG_HERE
            ast_log(LOG_NOTICE,"return (0) N is matched\n");
#endif
            return 0;
         }
         break;
      case 'X':
         if (*data < '0' || *data > '9') {
#ifdef NEED_DEBUG_HERE
            ast_log(LOG_NOTICE,"return (0) X is matched\n");
#endif
            return 0;
         }
         break;
      case 'Z':
         if (*data < '1' || *data > '9') {
#ifdef NEED_DEBUG_HERE
            ast_log(LOG_NOTICE,"return (0) Z is matched\n");
#endif
            return 0;
         }
         break;
      case '.':   /* Must match, even with more digits */
#ifdef NEED_DEBUG_HERE
         ast_log(LOG_NOTICE,"return (1) when '.' is matched\n");
#endif
         return 1;
      case '!':   /* Early match */
#ifdef NEED_DEBUG_HERE
         ast_log(LOG_NOTICE,"return (2) when '!' is matched\n");
#endif
         return 2;
      case ' ':
      case '-':   /* Ignore these in patterns */
         data--; /* compensate the final data++ */
         break;
      default:
         if (*data != *pattern) {
#ifdef NEED_DEBUG_HERE
            ast_log(LOG_NOTICE,"return (0) when *data(%c) != *pattern(%c)\n", *data, *pattern);
#endif
            return 0;
         }
         
      }
      data++;
      pattern++;
   }
   if (*data)        /* data longer than pattern, no match */ {
#ifdef NEED_DEBUG_HERE
      ast_log(LOG_NOTICE,"return (0) when data longer than pattern\n");
#endif
      return 0;
   }
   
   /*
    * match so far, but ran off the end of the data.
    * Depending on what is next, determine match or not.
    */
   if (*pattern == '\0' || *pattern == '/') {   /* exact match */
#ifdef NEED_DEBUG_HERE
      ast_log(LOG_NOTICE,"at end, return (%d) in 'exact match'\n", (mode==E_MATCHMORE) ? 0 : 1);
#endif
      return (mode == E_MATCHMORE) ? 0 : 1;  /* this is a failure for E_MATCHMORE */
   } else if (*pattern == '!')   {     /* early match */
#ifdef NEED_DEBUG_HERE
      ast_log(LOG_NOTICE,"at end, return (2) when '!' is matched\n");
#endif
      return 2;
   } else {                /* partial match */
#ifdef NEED_DEBUG_HERE
      ast_log(LOG_NOTICE,"at end, return (%d) which deps on E_MATCH\n", (mode == E_MATCH) ? 0 : 1);
#endif
      return (mode == E_MATCH) ? 0 : 1;   /* this is a failure for E_MATCH */
   }
}

/*
 * Wrapper around _extension_match_core() to do performance measurement
 * using the profiling code.
 */
static int extension_match_core(const char *pattern, const char *data, enum ext_match_t mode)
{
   int i;
   static int prof_id = -2;   /* marker for 'unallocated' id */
   if (prof_id == -2)
      prof_id = ast_add_profile("ext_match", 0);
   ast_mark(prof_id, 1);
   i = _extension_match_core(pattern, data, mode);
   ast_mark(prof_id, 0);
   return i;
}

int ast_extension_match(const char *pattern, const char *data)
{
   return extension_match_core(pattern, data, E_MATCH);
}

int ast_extension_close(const char *pattern, const char *data, int needmore)
{
   if (needmore != E_MATCHMORE && needmore != E_CANMATCH)
      ast_log(LOG_WARNING, "invalid argument %d\n", needmore);
   return extension_match_core(pattern, data, needmore);
}

struct fake_context /* this struct is purely for matching in the hashtab */
{
   ast_rwlock_t lock;         
   struct ast_exten *root;    
   struct ast_hashtab *root_table;            
   struct match_char *pattern_tree;       
   struct ast_context *next;  
   struct ast_include *includes;    
   struct ast_ignorepat *ignorepats;   
   const char *registrar;
   int refcount;
   AST_LIST_HEAD_NOLOCK(, ast_sw) alts;   
   ast_mutex_t macrolock;     
   char name[256];      
};

struct ast_context *ast_context_find(const char *name)
{
   struct ast_context *tmp = NULL;
   struct fake_context item;

   ast_copy_string(item.name, name, sizeof(item.name));

   ast_rdlock_contexts();
   if( contexts_table ) {
      tmp = ast_hashtab_lookup(contexts_table,&item);
   } else {
      while ( (tmp = ast_walk_contexts(tmp)) ) {
         if (!name || !strcasecmp(name, tmp->name))
            break;
      }
   }
   ast_unlock_contexts();
   return tmp;
}

#define STATUS_NO_CONTEXT  1
#define STATUS_NO_EXTENSION   2
#define STATUS_NO_PRIORITY 3
#define STATUS_NO_LABEL    4
#define STATUS_SUCCESS     5

static int matchcid(const char *cidpattern, const char *callerid)
{
   /* If the Caller*ID pattern is empty, then we're matching NO Caller*ID, so
      failing to get a number should count as a match, otherwise not */

   if (ast_strlen_zero(callerid))
      return ast_strlen_zero(cidpattern) ? 1 : 0;

   return ast_extension_match(cidpattern, callerid);
}

struct ast_exten *pbx_find_extension(struct ast_channel *chan,
   struct ast_context *bypass, struct pbx_find_info *q,
   const char *context, const char *exten, int priority,
   const char *label, const char *callerid, enum ext_match_t action)
{
   int x, res;
   struct ast_context *tmp = NULL;
   struct ast_exten *e = NULL, *eroot = NULL;
   struct ast_include *i = NULL;
   struct ast_sw *sw = NULL;
   struct ast_exten pattern = {NULL, };
   struct scoreboard score = {0, };
   struct ast_str *tmpdata = NULL;

   pattern.label = label;
   pattern.priority = priority;
#ifdef NEED_DEBUG_HERE
   ast_log(LOG_NOTICE,"Looking for cont/ext/prio/label/action = %s/%s/%d/%s/%d\n", context, exten, priority, label, (int)action);
#endif

   /* Initialize status if appropriate */
   if (q->stacklen == 0) {
      q->status = STATUS_NO_CONTEXT;
      q->swo = NULL;
      q->data = NULL;
      q->foundcontext = NULL;
   } else if (q->stacklen >= AST_PBX_MAX_STACK) {
      ast_log(LOG_WARNING, "Maximum PBX stack exceeded\n");
      return NULL;
   }

   /* Check first to see if we've already been checked */
   for (x = 0; x < q->stacklen; x++) {
      if (!strcasecmp(q->incstack[x], context))
         return NULL;
   }

   if (bypass) /* bypass means we only look there */
      tmp = bypass;
   else {   /* look in contexts */
      struct fake_context item;

      ast_copy_string(item.name, context, sizeof(item.name));

      tmp = ast_hashtab_lookup(contexts_table, &item);
#ifdef NOTNOW
      tmp = NULL;
      while ((tmp = ast_walk_contexts(tmp)) ) {
         if (!strcmp(tmp->name, context))
            break;
      }
#endif
      if (!tmp)
         return NULL;
      
   }

   if (q->status < STATUS_NO_EXTENSION)
      q->status = STATUS_NO_EXTENSION;
   
   /* Do a search for matching extension */

   eroot = NULL;
   score.total_specificity = 0;
   score.exten = 0;
   score.total_length = 0;
   if (!tmp->pattern_tree && tmp->root_table)
   {
      create_match_char_tree(tmp);
#ifdef NEED_DEBUG
      ast_log(LOG_DEBUG,"Tree Created in context %s:\n", context);
      log_match_char_tree(tmp->pattern_tree," ");
#endif
   }
#ifdef NEED_DEBUG
   ast_log(LOG_NOTICE,"The Trie we are searching in:\n");
   log_match_char_tree(tmp->pattern_tree, "::  ");
#endif

   do {
      if (!ast_strlen_zero(overrideswitch)) {
         char *osw = ast_strdupa(overrideswitch), *name;
         struct ast_switch *asw;
         ast_switch_f *aswf = NULL;
         char *datap;
         int eval = 0;

         name = strsep(&osw, "/");
         asw = pbx_findswitch(name);

         if (!asw) {
            ast_log(LOG_WARNING, "No such switch '%s'\n", name);
            break;
         }

         if (osw && strchr(osw, '$')) {
            eval = 1;
         }

         if (eval && !(tmpdata = ast_str_thread_get(&switch_data, 512))) {
            ast_log(LOG_WARNING, "Can't evaluate overrideswitch?!");
            break;
         } else if (eval) {
            /* Substitute variables now */
            pbx_substitute_variables_helper(chan, osw, tmpdata->str, tmpdata->len);
            datap = tmpdata->str;
         } else {
            datap = osw;
         }

         /* equivalent of extension_match_core() at the switch level */
         if (action == E_CANMATCH)
            aswf = asw->canmatch;
         else if (action == E_MATCHMORE)
            aswf = asw->matchmore;
         else /* action == E_MATCH */
            aswf = asw->exists;
         if (!aswf) {
            res = 0;
         } else {
            if (chan) {
               ast_autoservice_start(chan);
            }
            res = aswf(chan, context, exten, priority, callerid, datap);
            if (chan) {
               ast_autoservice_stop(chan);
            }
         }
         if (res) {  /* Got a match */
            q->swo = asw;
            q->data = datap;
            q->foundcontext = context;
            /* XXX keep status = STATUS_NO_CONTEXT ? */
            return NULL;
         }
      }
   } while (0);

   if (extenpatternmatchnew) {
      new_find_extension(exten, &score, tmp->pattern_tree, 0, 0, callerid, label, action);
      eroot = score.exten;
      
      if (score.last_char == '!' && action == E_MATCHMORE) {
         /* We match an extension ending in '!'.
          * The decision in this case is final and is NULL (no match).
          */
#ifdef NEED_DEBUG_HERE
         ast_log(LOG_NOTICE,"Returning MATCHMORE NULL with exclamation point.\n");
#endif
         return NULL;
      }
      
      if (!eroot && (action == E_CANMATCH || action == E_MATCHMORE) && score.canmatch_exten) {
         q->status = STATUS_SUCCESS;
#ifdef NEED_DEBUG_HERE
         ast_log(LOG_NOTICE,"Returning CANMATCH exten %s\n", score.canmatch_exten->exten);
#endif
         return score.canmatch_exten;
      }
      
      if ((action == E_MATCHMORE || action == E_CANMATCH)  && eroot) {
         if (score.node) {
            struct ast_exten *z = trie_find_next_match(score.node);
            if (z) {
#ifdef NEED_DEBUG_HERE
               ast_log(LOG_NOTICE,"Returning CANMATCH/MATCHMORE next_match exten %s\n", z->exten);
#endif
            } else {
               if (score.canmatch_exten) {
#ifdef NEED_DEBUG_HERE
                  ast_log(LOG_NOTICE,"Returning CANMATCH/MATCHMORE canmatchmatch exten %s(%p)\n", score.canmatch_exten->exten, score.canmatch_exten);
#endif
                  return score.canmatch_exten;
               } else {
#ifdef NEED_DEBUG_HERE
                  ast_log(LOG_NOTICE,"Returning CANMATCH/MATCHMORE next_match exten NULL\n");
#endif
               }
            }
            return z;
         }
#ifdef NEED_DEBUG_HERE
         ast_log(LOG_NOTICE,"Returning CANMATCH/MATCHMORE NULL (no next_match)\n");
#endif
         return NULL;  /* according to the code, complete matches are null matches in MATCHMORE mode */
      }
      
      if (eroot) {
         /* found entry, now look for the right priority */
         if (q->status < STATUS_NO_PRIORITY)
            q->status = STATUS_NO_PRIORITY;
         e = NULL;
         if (action == E_FINDLABEL && label ) {
            if (q->status < STATUS_NO_LABEL)
               q->status = STATUS_NO_LABEL;
            e = ast_hashtab_lookup(eroot->peer_label_table, &pattern);
         } else {
            e = ast_hashtab_lookup(eroot->peer_table, &pattern);
         }
         if (e) { /* found a valid match */
            q->status = STATUS_SUCCESS;
            q->foundcontext = context;
#ifdef NEED_DEBUG_HERE
            ast_log(LOG_NOTICE,"Returning complete match of exten %s\n", e->exten);
#endif
            return e;
         }
      }
   } else {   /* the old/current default exten pattern match algorithm */
      
      /* scan the list trying to match extension and CID */
      eroot = NULL;
      while ( (eroot = ast_walk_context_extensions(tmp, eroot)) ) {
         int match = extension_match_core(eroot->exten, exten, action);
         /* 0 on fail, 1 on match, 2 on earlymatch */
         
         if (!match || (eroot->matchcid && !matchcid(eroot->cidmatch, callerid)))
            continue;   /* keep trying */
         if (match == 2 && action == E_MATCHMORE) {
            /* We match an extension ending in '!'.
             * The decision in this case is final and is NULL (no match).
             */
            return NULL;
         }
         /* found entry, now look for the right priority */
         if (q->status < STATUS_NO_PRIORITY)
            q->status = STATUS_NO_PRIORITY;
         e = NULL;
         if (action == E_FINDLABEL && label ) {
            if (q->status < STATUS_NO_LABEL)
               q->status = STATUS_NO_LABEL;
            e = ast_hashtab_lookup(eroot->peer_label_table, &pattern);
         } else {
            e = ast_hashtab_lookup(eroot->peer_table, &pattern);
         }
#ifdef NOTNOW
         while ( (e = ast_walk_extension_priorities(eroot, e)) ) {
            /* Match label or priority */
            if (action == E_FINDLABEL) {
               if (q->status < STATUS_NO_LABEL)
                  q->status = STATUS_NO_LABEL;
               if (label && e->label && !strcmp(label, e->label))
                  break;   /* found it */
            } else if (e->priority == priority) {
               break;   /* found it */
            } /* else keep searching */
         }
#endif
         if (e) { /* found a valid match */
            q->status = STATUS_SUCCESS;
            q->foundcontext = context;
            return e;
         }
      }
   }
   
   
   /* Check alternative switches */
   AST_LIST_TRAVERSE(&tmp->alts, sw, list) {
      struct ast_switch *asw = pbx_findswitch(sw->name);
      ast_switch_f *aswf = NULL;
      char *datap;

      if (!asw) {
         ast_log(LOG_WARNING, "No such switch '%s'\n", sw->name);
         continue;
      }
      /* Substitute variables now */
      
      if (sw->eval) {
         if (!(tmpdata = ast_str_thread_get(&switch_data, 512))) {
            ast_log(LOG_WARNING, "Can't evaluate switch?!");
            continue;
         }
         pbx_substitute_variables_helper(chan, sw->data, tmpdata->str, tmpdata->len);
      }

      /* equivalent of extension_match_core() at the switch level */
      if (action == E_CANMATCH)
         aswf = asw->canmatch;
      else if (action == E_MATCHMORE)
         aswf = asw->matchmore;
      else /* action == E_MATCH */
         aswf = asw->exists;
      datap = sw->eval ? tmpdata->str : sw->data;
      if (!aswf)
         res = 0;
      else {
         if (chan)
            ast_autoservice_start(chan);
         res = aswf(chan, context, exten, priority, callerid, datap);
         if (chan)
            ast_autoservice_stop(chan);
      }
      if (res) {  /* Got a match */
         q->swo = asw;
         q->data = datap;
         q->foundcontext = context;
         /* XXX keep status = STATUS_NO_CONTEXT ? */
         return NULL;
      }
   }
   q->incstack[q->stacklen++] = tmp->name;   /* Setup the stack */
   /* Now try any includes we have in this context */
   for (i = tmp->includes; i; i = i->next) {
      if (include_valid(i)) {
         if ((e = pbx_find_extension(chan, bypass, q, i->rname, exten, priority, label, callerid, action))) {
#ifdef NEED_DEBUG_HERE
            ast_log(LOG_NOTICE,"Returning recursive match of %s\n", e->exten);
#endif
            return e;
         }
         if (q->swo)
            return NULL;
      }
   }
   return NULL;
}

/*! 
 * \brief extract offset:length from variable name.
 * \return 1 if there is a offset:length part, which is
 * trimmed off (values go into variables)
 */
static int parse_variable_name(char *var, int *offset, int *length, int *isfunc)
{
   int parens = 0;

   *offset = 0;
   *length = INT_MAX;
   *isfunc = 0;
   for (; *var; var++) {
      if (*var == '(') {
         (*isfunc)++;
         parens++;
      } else if (*var == ')') {
         parens--;
      } else if (*var == ':' && parens == 0) {
         *var++ = '\0';
         sscanf(var, "%30d:%30d", offset, length);
         return 1; /* offset:length valid */
      }
   }
   return 0;
}

/*! 
 *\brief takes a substring. It is ok to call with value == workspace.
 * \param value
 * \param offset < 0 means start from the end of the string and set the beginning
 *   to be that many characters back.
 * \param length is the length of the substring, a value less than 0 means to leave
 * that many off the end.
 * \param workspace
 * \param workspace_len
 * Always return a copy in workspace.
 */
static char *substring(const char *value, int offset, int length, char *workspace, size_t workspace_len)
{
   char *ret = workspace;
   int lr;  /* length of the input string after the copy */

   ast_copy_string(workspace, value, workspace_len); /* always make a copy */

   lr = strlen(ret); /* compute length after copy, so we never go out of the workspace */

   /* Quick check if no need to do anything */
   if (offset == 0 && length >= lr) /* take the whole string */
      return ret;

   if (offset < 0)   {  /* translate negative offset into positive ones */
      offset = lr + offset;
      if (offset < 0) /* If the negative offset was greater than the length of the string, just start at the beginning */
         offset = 0;
   }

   /* too large offset result in empty string so we know what to return */
   if (offset >= lr)
      return ret + lr;  /* the final '\0' */

   ret += offset;    /* move to the start position */
   if (length >= 0 && length < lr - offset)  /* truncate if necessary */
      ret[length] = '\0';
   else if (length < 0) {
      if (lr > offset - length) /* After we remove from the front and from the rear, is there anything left? */
         ret[lr + length - offset] = '\0';
      else
         ret[0] = '\0';
   }

   return ret;
}

/*! \brief  Support for Asterisk built-in variables in the dialplan

\note See also
   - \ref AstVar  Channel variables
   - \ref AstCauses The HANGUPCAUSE variable
 */
void pbx_retrieve_variable(struct ast_channel *c, const char *var, char **ret, char *workspace, int workspacelen, struct varshead *headp)
{
   const char not_found = '\0';
   char *tmpvar;
   const char *s; /* the result */
   int offset, length;
   int i, need_substring;
   struct varshead *places[2] = { headp, &globals };  /* list of places where we may look */

   if (c) {
      ast_channel_lock(c);
      places[0] = &c->varshead;
   }
   /*
    * Make a copy of var because parse_variable_name() modifies the string.
    * Then if called directly, we might need to run substring() on the result;
    * remember this for later in 'need_substring', 'offset' and 'length'
    */
   tmpvar = ast_strdupa(var); /* parse_variable_name modifies the string */
   need_substring = parse_variable_name(tmpvar, &offset, &length, &i /* ignored */);

   /*
    * Look first into predefined variables, then into variable lists.
    * Variable 's' points to the result, according to the following rules:
    * s == &not_found (set at the beginning) means that we did not find a
    * matching variable and need to look into more places.
    * If s != &not_found, s is a valid result string as follows:
    * s = NULL if the variable does not have a value;
    * you typically do this when looking for an unset predefined variable.
    * s = workspace if the result has been assembled there;
    * typically done when the result is built e.g. with an snprintf(),
    * so we don't need to do an additional copy.
    * s != workspace in case we have a string, that needs to be copied
    * (the ast_copy_string is done once for all at the end).
    * Typically done when the result is already available in some string.
    */
   s = &not_found;   /* default value */
   if (c) { /* This group requires a valid channel */
      /* Names with common parts are looked up a piece at a time using strncmp. */
      if (!strncmp(var, "CALL", 4)) {
         if (!strncmp(var + 4, "ING", 3)) {
            if (!strcmp(var + 7, "PRES")) {        /* CALLINGPRES */
               snprintf(workspace, workspacelen, "%d", c->cid.cid_pres);
               s = workspace;
            } else if (!strcmp(var + 7, "ANI2")) {    /* CALLINGANI2 */
               snprintf(workspace, workspacelen, "%d", c->cid.cid_ani2);
               s = workspace;
            } else if (!strcmp(var + 7, "TON")) {     /* CALLINGTON */
               snprintf(workspace, workspacelen, "%d", c->cid.cid_ton);
               s = workspace;
            } else if (!strcmp(var + 7, "TNS")) {     /* CALLINGTNS */
               snprintf(workspace, workspacelen, "%d", c->cid.cid_tns);
               s = workspace;
            }
         }
      } else if (!strcmp(var, "HINT")) {
         s = ast_get_hint(workspace, workspacelen, NULL, 0, c, c->context, c->exten) ? workspace : NULL;
      } else if (!strcmp(var, "HINTNAME")) {
         s = ast_get_hint(NULL, 0, workspace, workspacelen, c, c->context, c->exten) ? workspace : NULL;
      } else if (!strcmp(var, "EXTEN")) {
         s = c->exten;
      } else if (!strcmp(var, "CONTEXT")) {
         s = c->context;
      } else if (!strcmp(var, "PRIORITY")) {
         snprintf(workspace, workspacelen, "%d", c->priority);
         s = workspace;
      } else if (!strcmp(var, "CHANNEL")) {
         s = c->name;
      } else if (!strcmp(var, "UNIQUEID")) {
         s = c->uniqueid;
      } else if (!strcmp(var, "HANGUPCAUSE")) {
         snprintf(workspace, workspacelen, "%d", c->hangupcause);
         s = workspace;
      }
   }
   if (s == &not_found) { /* look for more */
      if (!strcmp(var, "EPOCH")) {
         snprintf(workspace, workspacelen, "%u",(int)time(NULL));
         s = workspace;
      } else if (!strcmp(var, "SYSTEMNAME")) {
         s = ast_config_AST_SYSTEM_NAME;
      } else if (!strcmp(var, "ENTITYID")) {
         ast_eid_to_str(workspace, workspacelen, &ast_eid_default);
         s = workspace;
      }
   }
   /* if not found, look into chanvars or global vars */
   for (i = 0; s == &not_found && i < ARRAY_LEN(places); i++) {
      struct ast_var_t *variables;
      if (!places[i])
         continue;
      if (places[i] == &globals)
         ast_rwlock_rdlock(&globalslock);
      AST_LIST_TRAVERSE(places[i], variables, entries) {
         if (!strcasecmp(ast_var_name(variables), var)) {
            s = ast_var_value(variables);
            break;
         }
      }
      if (places[i] == &globals)
         ast_rwlock_unlock(&globalslock);
   }
   if (s == &not_found || s == NULL)
      *ret = NULL;
   else {
      if (s != workspace)
         ast_copy_string(workspace, s, workspacelen);
      *ret = workspace;
      if (need_substring)
         *ret = substring(*ret, offset, length, workspace, workspacelen);
   }

   if (c)
      ast_channel_unlock(c);
}

static void exception_store_free(void *data)
{
   struct pbx_exception *exception = data;
   ast_string_field_free_memory(exception);
   ast_free(exception);
}

static struct ast_datastore_info exception_store_info = {
   .type = "EXCEPTION",
   .destroy = exception_store_free,
};

int pbx_builtin_raise_exception(struct ast_channel *chan, void *vreason)
{
   const char *reason = vreason;
   struct ast_datastore *ds = ast_channel_datastore_find(chan, &exception_store_info, NULL);
   struct pbx_exception *exception = NULL;

   if (!ds) {
      ds = ast_datastore_alloc(&exception_store_info, NULL);
      if (!ds)
         return -1;
      exception = ast_calloc(1, sizeof(struct pbx_exception));
      if (!exception) {
         ast_datastore_free(ds);
         return -1;
      }
      if (ast_string_field_init(exception, 128)) {
         ast_free(exception);
         ast_datastore_free(ds);
         return -1;
      }
      ds->data = exception;
      ast_channel_datastore_add(chan, ds);
   } else
      exception = ds->data;

   ast_string_field_set(exception, reason, reason);
   ast_string_field_set(exception, context, chan->context);
   ast_string_field_set(exception, exten, chan->exten);
   exception->priority = chan->priority;
   set_ext_pri(chan, "e", 0);
   return 0;
}

static int acf_exception_read(struct ast_channel *chan, const char *name, char *data, char *buf, size_t buflen)
{
   struct ast_datastore *ds = ast_channel_datastore_find(chan, &exception_store_info, NULL);
   struct pbx_exception *exception = NULL;
   if (!ds || !ds->data)
      return -1;
   exception = ds->data;
   if (!strcasecmp(data, "REASON"))
      ast_copy_string(buf, exception->reason, buflen);
   else if (!strcasecmp(data, "CONTEXT"))
      ast_copy_string(buf, exception->context, buflen);
   else if (!strncasecmp(data, "EXTEN", 5))
      ast_copy_string(buf, exception->exten, buflen);
   else if (!strcasecmp(data, "PRIORITY"))
      snprintf(buf, buflen, "%d", exception->priority);
   else
      return -1;
   return 0;
}

static struct ast_custom_function exception_function = {
   .name = "EXCEPTION",
   .synopsis = "Retrieve the details of the current dialplan exception",
   .desc =
"The following fields are available for retrieval:\n"
"  reason    INVALID, ERROR, RESPONSETIMEOUT, ABSOLUTETIMEOUT, or custom\n"
"               value set by the RaiseException() application\n"
"  context   The context executing when the exception occurred\n"
"  exten     The extension executing when the exception occurred\n"
"  priority  The numeric priority executing when the exception occurred\n",
   .syntax = "EXCEPTION(<field>)",
   .read = acf_exception_read,
};

static char *handle_show_functions(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   struct ast_custom_function *acf;
   int count_acf = 0;
   int like = 0;

   switch (cmd) {
   case CLI_INIT:
      e->command = "core show functions [like]";
      e->usage = 
         "Usage: core show functions [like <text>]\n"
         "       List builtin functions, optionally only those matching a given string\n";
      return NULL;
   case CLI_GENERATE:
      return NULL;
   }

   if (a->argc == 5 && (!strcmp(a->argv[3], "like")) ) {
      like = 1;
   } else if (a->argc != 3) {
      return CLI_SHOWUSAGE;
   }

   ast_cli(a->fd, "%s Custom Functions:\n--------------------------------------------------------------------------------\n", like ? "Matching" : "Installed");

   AST_RWLIST_RDLOCK(&acf_root);
   AST_RWLIST_TRAVERSE(&acf_root, acf, acflist) {
      if (!like || strstr(acf->name, a->argv[4])) {
         count_acf++;
         ast_cli(a->fd, "%-20.20s  %-35.35s  %s\n", acf->name, acf->syntax, acf->synopsis);
      }
   }
   AST_RWLIST_UNLOCK(&acf_root);

   ast_cli(a->fd, "%d %scustom functions installed.\n", count_acf, like ? "matching " : "");

   return CLI_SUCCESS;
}

static char *handle_show_function(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   struct ast_custom_function *acf;
   /* Maximum number of characters added by terminal coloring is 22 */
   char infotitle[64 + AST_MAX_APP + 22], syntitle[40], destitle[40];
   char info[64 + AST_MAX_APP], *synopsis = NULL, *description = NULL;
   char stxtitle[40], *syntax = NULL;
   int synopsis_size, description_size, syntax_size;
   char *ret = NULL;
   int which = 0;
   int wordlen;

   switch (cmd) {
   case CLI_INIT:
      e->command = "core show function";
      e->usage = 
         "Usage: core show function <function>\n"
         "       Describe a particular dialplan function.\n";
      return NULL;
   case CLI_GENERATE:   
      wordlen = strlen(a->word);
      /* case-insensitive for convenience in this 'complete' function */
      AST_RWLIST_RDLOCK(&acf_root);
      AST_RWLIST_TRAVERSE(&acf_root, acf, acflist) {
         if (!strncasecmp(a->word, acf->name, wordlen) && ++which > a->n) {
            ret = ast_strdup(acf->name);
            break;
         }
      }
      AST_RWLIST_UNLOCK(&acf_root);

      return ret;
   }

   if (a->argc < 4)
      return CLI_SHOWUSAGE;

   if (!(acf = ast_custom_function_find(a->argv[3]))) {
      ast_cli(a->fd, "No function by that name registered.\n");
      return CLI_FAILURE;

   }

   if (acf->synopsis)
      synopsis_size = strlen(acf->synopsis) + 23;
   else
      synopsis_size = strlen("Not available") + 23;
   synopsis = alloca(synopsis_size);

   if (acf->desc)
      description_size = strlen(acf->desc) + 23;
   else
      description_size = strlen("Not available") + 23;
   description = alloca(description_size);

   if (acf->syntax)
      syntax_size = strlen(acf->syntax) + 23;
   else
      syntax_size = strlen("Not available") + 23;
   syntax = alloca(syntax_size);

   snprintf(info, 64 + AST_MAX_APP, "\n  -= Info about function '%s' =- \n\n", acf->name);
   term_color(infotitle, info, COLOR_MAGENTA, 0, 64 + AST_MAX_APP + 22);
   term_color(stxtitle, "[Syntax]\n", COLOR_MAGENTA, 0, 40);
   term_color(syntitle, "[Synopsis]\n", COLOR_MAGENTA, 0, 40);
   term_color(destitle, "[Description]\n", COLOR_MAGENTA, 0, 40);
   term_color(syntax,
         acf->syntax ? acf->syntax : "Not available",
         COLOR_CYAN, 0, syntax_size);
   term_color(synopsis,
         acf->synopsis ? acf->synopsis : "Not available",
         COLOR_CYAN, 0, synopsis_size);
   term_color(description,
         acf->desc ? acf->desc : "Not available",
         COLOR_CYAN, 0, description_size);

   ast_cli(a->fd,"%s%s%s\n\n%s%s\n\n%s%s\n", infotitle, stxtitle, syntax, syntitle, synopsis, destitle, description);

   return CLI_SUCCESS;
}

struct ast_custom_function *ast_custom_function_find(const char *name)
{
   struct ast_custom_function *acf = NULL;

   AST_RWLIST_RDLOCK(&acf_root);
   AST_RWLIST_TRAVERSE(&acf_root, acf, acflist) {
      if (!strcmp(name, acf->name))
         break;
   }
   AST_RWLIST_UNLOCK(&acf_root);

   return acf;
}

int ast_custom_function_unregister(struct ast_custom_function *acf)
{
   struct ast_custom_function *cur;

   if (!acf)
      return -1;

   AST_RWLIST_WRLOCK(&acf_root);
   if ((cur = AST_RWLIST_REMOVE(&acf_root, acf, acflist)))
      ast_verb(2, "Unregistered custom function %s\n", cur->name);
   AST_RWLIST_UNLOCK(&acf_root);

   return cur ? 0 : -1;
}

int __ast_custom_function_register(struct ast_custom_function *acf, struct ast_module *mod)
{
   struct ast_custom_function *cur;
   char tmps[80];

   if (!acf)
      return -1;

   acf->mod = mod;

   AST_RWLIST_WRLOCK(&acf_root);

   AST_RWLIST_TRAVERSE(&acf_root, cur, acflist) {
      if (!strcmp(acf->name, cur->name)) {
         ast_log(LOG_ERROR, "Function %s already registered.\n", acf->name);
         AST_RWLIST_UNLOCK(&acf_root);
         return -1;
      }
   }

   /* Store in alphabetical order */
   AST_RWLIST_TRAVERSE_SAFE_BEGIN(&acf_root, cur, acflist) {
      if (strcasecmp(acf->name, cur->name) < 0) {
         AST_RWLIST_INSERT_BEFORE_CURRENT(acf, acflist);
         break;
      }
   }
   AST_RWLIST_TRAVERSE_SAFE_END;
   if (!cur)
      AST_RWLIST_INSERT_TAIL(&acf_root, acf, acflist);

   AST_RWLIST_UNLOCK(&acf_root);

   ast_verb(2, "Registered custom function '%s'\n", term_color(tmps, acf->name, COLOR_BRCYAN, 0, sizeof(tmps)));

   return 0;
}

/*! \brief return a pointer to the arguments of the function,
 * and terminates the function name with '\\0'
 */
static char *func_args(char *function)
{
   char *args = strchr(function, '(');

   if (!args)
      ast_log(LOG_WARNING, "Function doesn't contain parentheses.  Assuming null argument.\n");
   else {
      char *p;
      *args++ = '\0';
      if ((p = strrchr(args, ')')) )
         *p = '\0';
      else
         ast_log(LOG_WARNING, "Can't find trailing parenthesis?\n");
   }
   return args;
}

int ast_func_read(struct ast_channel *chan, const char *function, char *workspace, size_t len)
{
   char *copy = ast_strdupa(function);
   char *args = func_args(copy);
   struct ast_custom_function *acfptr = ast_custom_function_find(copy);

   if (acfptr == NULL)
      ast_log(LOG_ERROR, "Function %s not registered\n", copy);
   else if (!acfptr->read)
      ast_log(LOG_ERROR, "Function %s cannot be read\n", copy);
   else {
      int res;
      struct ast_module_user *u = NULL;
      if (acfptr->mod)
         u = __ast_module_user_add(acfptr->mod, chan);
      res = acfptr->read(chan, copy, args, workspace, len);
      if (acfptr->mod && u)
         __ast_module_user_remove(acfptr->mod, u);
      return res;
   }
   return -1;
}

int ast_func_write(struct ast_channel *chan, const char *function, const char *value)
{
   char *copy = ast_strdupa(function);
   char *args = func_args(copy);
   struct ast_custom_function *acfptr = ast_custom_function_find(copy);

   if (acfptr == NULL)
      ast_log(LOG_ERROR, "Function %s not registered\n", copy);
   else if (!acfptr->write)
      ast_log(LOG_ERROR, "Function %s cannot be written to\n", copy);
   else {
      int res;
      struct ast_module_user *u = NULL;
      if (acfptr->mod)
         u = __ast_module_user_add(acfptr->mod, chan);
      res = acfptr->write(chan, copy, args, value);
      if (acfptr->mod && u)
         __ast_module_user_remove(acfptr->mod, u);
      return res;
   }

   return -1;
}

static void pbx_substitute_variables_helper_full(struct ast_channel *c, struct varshead *headp, const char *cp1, char *cp2, int count)
{
   /* Substitutes variables into cp2, based on string cp1, cp2 NO LONGER NEEDS TO BE ZEROED OUT!!!!  */
   char *cp4;
   const char *tmp, *whereweare;
   int length, offset, offset2, isfunction;
   char *workspace = NULL;
   char *ltmp = NULL, *var = NULL;
   char *nextvar, *nextexp, *nextthing;
   char *vars, *vare;
   int pos, brackets, needsub, len;
   
   *cp2 = 0; /* just in case nothing ends up there */
   whereweare=tmp=cp1;
   while (!ast_strlen_zero(whereweare) && count) {
      /* Assume we're copying the whole remaining string */
      pos = strlen(whereweare);
      nextvar = NULL;
      nextexp = NULL;
      nextthing = strchr(whereweare, '$');
      if (nextthing) {
         switch (nextthing[1]) {
         case '{':
            nextvar = nextthing;
            pos = nextvar - whereweare;
            break;
         case '[':
            nextexp = nextthing;
            pos = nextexp - whereweare;
            break;
         default:
            pos = 1;
         }
      }

      if (pos) {
         /* Can't copy more than 'count' bytes */
         if (pos > count)
            pos = count;

         /* Copy that many bytes */
         memcpy(cp2, whereweare, pos);

         count -= pos;
         cp2 += pos;
         whereweare += pos;
         *cp2 = 0;
      }

      if (nextvar) {
         /* We have a variable.  Find the start and end, and determine
            if we are going to have to recursively call ourselves on the
            contents */
         vars = vare = nextvar + 2;
         brackets = 1;
         needsub = 0;

         /* Find the end of it */
         while (brackets && *vare) {
            if ((vare[0] == '$') && (vare[1] == '{')) {
               needsub++;
            } else if (vare[0] == '{') {
               brackets++;
            } else if (vare[0] == '}') {
               brackets--;
            } else if ((vare[0] == '$') && (vare[1] == '['))
               needsub++;
            vare++;
         }
         if (brackets)
            ast_log(LOG_WARNING, "Error in extension logic (missing '}')\n");
         len = vare - vars - 1;

         /* Skip totally over variable string */
         whereweare += (len + 3);

         if (!var)
            var = alloca(VAR_BUF_SIZE);

         /* Store variable name (and truncate) */
         ast_copy_string(var, vars, len + 1);

         /* Substitute if necessary */
         if (needsub) {
            if (!ltmp)
               ltmp = alloca(VAR_BUF_SIZE);

            pbx_substitute_variables_helper_full(c, headp, var, ltmp, VAR_BUF_SIZE - 1);
            vars = ltmp;
         } else {
            vars = var;
         }

         if (!workspace)
            workspace = alloca(VAR_BUF_SIZE);

         workspace[0] = '\0';

         parse_variable_name(vars, &offset, &offset2, &isfunction);
         if (isfunction) {
            /* Evaluate function */
            if (c || !headp)
               cp4 = ast_func_read(c, vars, workspace, VAR_BUF_SIZE) ? NULL : workspace;
            else {
               struct varshead old;
               struct ast_channel *bogus = ast_channel_alloc(0, 0, "", "", "", "", "", 0, "Bogus/%p", vars);
               if (bogus) {
                  memcpy(&old, &bogus->varshead, sizeof(old));
                  memcpy(&bogus->varshead, headp, sizeof(bogus->varshead));
                  cp4 = ast_func_read(bogus, vars, workspace, VAR_BUF_SIZE) ? NULL : workspace;
                  /* Don't deallocate the varshead that was passed in */
                  memcpy(&bogus->varshead, &old, sizeof(bogus->varshead));
                  ast_channel_free(bogus);
               } else
                  ast_log(LOG_ERROR, "Unable to allocate bogus channel for variable substitution.  Function results may be blank.\n");
            }
            ast_debug(2, "Function result is '%s'\n", cp4 ? cp4 : "(null)");
         } else {
            /* Retrieve variable value */
            pbx_retrieve_variable(c, vars, &cp4, workspace, VAR_BUF_SIZE, headp);
         }
         if (cp4) {
            cp4 = substring(cp4, offset, offset2, workspace, VAR_BUF_SIZE);

            length = strlen(cp4);
            if (length > count)
               length = count;
            memcpy(cp2, cp4, length);
            count -= length;
            cp2 += length;
            *cp2 = 0;
         }
      } else if (nextexp) {
         /* We have an expression.  Find the start and end, and determine
            if we are going to have to recursively call ourselves on the
            contents */
         vars = vare = nextexp + 2;
         brackets = 1;
         needsub = 0;

         /* Find the end of it */
         while (brackets && *vare) {
            if ((vare[0] == '$') && (vare[1] == '[')) {
               needsub++;
               brackets++;
               vare++;
            } else if (vare[0] == '[') {
               brackets++;
            } else if (vare[0] == ']') {
               brackets--;
            } else if ((vare[0] == '$') && (vare[1] == '{')) {
               needsub++;
               vare++;
            }
            vare++;
         }
         if (brackets)
            ast_log(LOG_WARNING, "Error in extension logic (missing ']')\n");
         len = vare - vars - 1;

         /* Skip totally over expression */
         whereweare += (len + 3);

         if (!var)
            var = alloca(VAR_BUF_SIZE);

         /* Store variable name (and truncate) */
         ast_copy_string(var, vars, len + 1);

         /* Substitute if necessary */
         if (needsub) {
            if (!ltmp)
               ltmp = alloca(VAR_BUF_SIZE);

            pbx_substitute_variables_helper_full(c, headp, var, ltmp, VAR_BUF_SIZE - 1);
            vars = ltmp;
         } else {
            vars = var;
         }

         length = ast_expr(vars, cp2, count, c);

         if (length) {
            ast_debug(1, "Expression result is '%s'\n", cp2);
            count -= length;
            cp2 += length;
            *cp2 = 0;
         }
      }
   }
}

void pbx_substitute_variables_helper(struct ast_channel *c, const char *cp1, char *cp2, int count)
{
   pbx_substitute_variables_helper_full(c, (c) ? &c->varshead : NULL, cp1, cp2, count);
}

void pbx_substitute_variables_varshead(struct varshead *headp, const char *cp1, char *cp2, int count)
{
   pbx_substitute_variables_helper_full(NULL, headp, cp1, cp2, count);
}

static void pbx_substitute_variables(char *passdata, int datalen, struct ast_channel *c, struct ast_exten *e)
{
   const char *tmp;

   /* Nothing more to do */
   if (!e->data)
      return;

   /* No variables or expressions in e->data, so why scan it? */
   if ((!(tmp = strchr(e->data, '$'))) || (!strstr(tmp, "${") && !strstr(tmp, "$["))) {
      ast_copy_string(passdata, e->data, datalen);
      return;
   }

   pbx_substitute_variables_helper(c, e->data, passdata, datalen - 1);
}

/*! 
 * \brief The return value depends on the action:
 *
 * E_MATCH, E_CANMATCH, E_MATCHMORE require a real match,
 * and return 0 on failure, -1 on match;
 * E_FINDLABEL maps the label to a priority, and returns
 * the priority on success, ... XXX
 * E_SPAWN, spawn an application,
 * 
 * \retval 0 on success.
 * \retval  -1 on failure.
 *
 * \note The channel is auto-serviced in this function, because doing an extension
 * match may block for a long time.  For example, if the lookup has to use a network
 * dialplan switch, such as DUNDi or IAX2, it may take a while.  However, the channel
 * auto-service code will queue up any important signalling frames to be processed
 * after this is done.
 */
static int pbx_extension_helper(struct ast_channel *c, struct ast_context *con,
  const char *context, const char *exten, int priority,
  const char *label, const char *callerid, enum ext_match_t action, int *found, int combined_find_spawn)
{
   struct ast_exten *e;
   struct ast_app *app;
   int res;
   struct pbx_find_info q = { .stacklen = 0 }; /* the rest is reset in pbx_find_extension */
   char passdata[EXT_DATA_SIZE];

   int matching_action = (action == E_MATCH || action == E_CANMATCH || action == E_MATCHMORE);

   ast_rdlock_contexts();
   if (found)
      *found = 0;

   e = pbx_find_extension(c, con, &q, context, exten, priority, label, callerid, action);
   if (e) {
      if (found)
         *found = 1;
      if (matching_action) {
         ast_unlock_contexts();
         return -1;  /* success, we found it */
      } else if (action == E_FINDLABEL) { /* map the label to a priority */
         res = e->priority;
         ast_unlock_contexts();
         return res; /* the priority we were looking for */
      } else { /* spawn */
         if (!e->cached_app)
            e->cached_app = pbx_findapp(e->app);
         app = e->cached_app;
         ast_unlock_contexts();
         if (!app) {
            ast_log(LOG_WARNING, "No application '%s' for extension (%s, %s, %d)\n", e->app, context, exten, priority);
            return -1;
         }
         if (c->context != context)
            ast_copy_string(c->context, context, sizeof(c->context));
         if (c->exten != exten)
            ast_copy_string(c->exten, exten, sizeof(c->exten));
         c->priority = priority;
         pbx_substitute_variables(passdata, sizeof(passdata), c, e);
#ifdef CHANNEL_TRACE
         ast_channel_trace_update(c);
#endif
         ast_debug(1, "Launching '%s'\n", app->name);
         if (VERBOSITY_ATLEAST(3)) {
            char tmp[80], tmp2[80], tmp3[EXT_DATA_SIZE];
            ast_verb(3, "Executing [%s@%s:%d] %s(\"%s\", \"%s\") %s\n",
               exten, context, priority,
               term_color(tmp, app->name, COLOR_BRCYAN, 0, sizeof(tmp)),
               term_color(tmp2, c->name, COLOR_BRMAGENTA, 0, sizeof(tmp2)),
               term_color(tmp3, passdata, COLOR_BRMAGENTA, 0, sizeof(tmp3)),
               "in new stack");
         }
         manager_event(EVENT_FLAG_DIALPLAN, "Newexten",
               "Channel: %s\r\n"
               "Context: %s\r\n"
               "Extension: %s\r\n"
               "Priority: %d\r\n"
               "Application: %s\r\n"
               "AppData: %s\r\n"
               "Uniqueid: %s\r\n",
               c->name, c->context, c->exten, c->priority, app->name, passdata, c->uniqueid);
         return pbx_exec(c, app, passdata);  /* 0 on success, -1 on failure */
      }
   } else if (q.swo) {  /* not found here, but in another switch */
      if (found)
         *found = 1;
      ast_unlock_contexts();
      if (matching_action) {
         return -1;
      } else {
         if (!q.swo->exec) {
            ast_log(LOG_WARNING, "No execution engine for switch %s\n", q.swo->name);
            res = -1;
         }
         return q.swo->exec(c, q.foundcontext ? q.foundcontext : context, exten, priority, callerid, q.data);
      }
   } else { /* not found anywhere, see what happened */
      ast_unlock_contexts();
      switch (q.status) {
      case STATUS_NO_CONTEXT:
         if (!matching_action && !combined_find_spawn)
            ast_log(LOG_NOTICE, "Cannot find extension context '%s'\n", context);
         break;
      case STATUS_NO_EXTENSION:
         if (!matching_action && !combined_find_spawn)
            ast_log(LOG_NOTICE, "Cannot find extension '%s' in context '%s'\n", exten, context);
         break;
      case STATUS_NO_PRIORITY:
         if (!matching_action && !combined_find_spawn)
            ast_log(LOG_NOTICE, "No such priority %d in extension '%s' in context '%s'\n", priority, exten, context);
         break;
      case STATUS_NO_LABEL:
         if (context && !combined_find_spawn)
            ast_log(LOG_NOTICE, "No such label '%s' in extension '%s' in context '%s'\n", label, exten, context);
         break;
      default:
         ast_debug(1, "Shouldn't happen!\n");
      }

      return (matching_action) ? 0 : -1;
   }
}

/*! \brief Find hint for given extension in context */
static struct ast_exten *ast_hint_extension_nolock(struct ast_channel *c, const char *context, const char *exten)
{
   struct pbx_find_info q = { .stacklen = 0 }; /* the rest is set in pbx_find_context */
   return pbx_find_extension(c, NULL, &q, context, exten, PRIORITY_HINT, NULL, "", E_MATCH);
}

static struct ast_exten *ast_hint_extension(struct ast_channel *c, const char *context, const char *exten)
{
   struct ast_exten *e;
   ast_rdlock_contexts();
   e = ast_hint_extension_nolock(c, context, exten);
   ast_unlock_contexts();
   return e;
}

enum ast_extension_states ast_devstate_to_extenstate(enum ast_device_state devstate)
{
   switch (devstate) {
   case AST_DEVICE_ONHOLD:
      return AST_EXTENSION_ONHOLD;
   case AST_DEVICE_BUSY:
      return AST_EXTENSION_BUSY;
   case AST_DEVICE_UNAVAILABLE:
   case AST_DEVICE_UNKNOWN:
   case AST_DEVICE_INVALID:
      return AST_EXTENSION_UNAVAILABLE;
   case AST_DEVICE_RINGINUSE:
      return (AST_EXTENSION_INUSE | AST_EXTENSION_RINGING);
   case AST_DEVICE_RINGING:
      return AST_EXTENSION_RINGING;
   case AST_DEVICE_INUSE:
      return AST_EXTENSION_INUSE;
   case AST_DEVICE_NOT_INUSE:
      return AST_EXTENSION_NOT_INUSE;
   case AST_DEVICE_TOTAL: /* not a device state, included for completeness */
      break;
   }

   return AST_EXTENSION_NOT_INUSE;
}

/*! \brief Check state of extension by using hints */
static int ast_extension_state2(struct ast_exten *e)
{
   char hint[AST_MAX_EXTENSION] = "";
   char *cur, *rest;
   struct ast_devstate_aggregate agg;

   if (!e)
      return -1;

   ast_devstate_aggregate_init(&agg);

   ast_copy_string(hint, ast_get_extension_app(e), sizeof(hint));

   rest = hint;   /* One or more devices separated with a & character */

   while ( (cur = strsep(&rest, "&")) ) {
      ast_devstate_aggregate_add(&agg, ast_device_state(cur));
   }

   return ast_devstate_to_extenstate(ast_devstate_aggregate_result(&agg));
}

/*! \brief Return extension_state as string */
const char *ast_extension_state2str(int extension_state)
{
   int i;

   for (i = 0; (i < ARRAY_LEN(extension_states)); i++) {
      if (extension_states[i].extension_state == extension_state)
         return extension_states[i].text;
   }
   return "Unknown";
}

/*! \brief Check extension state for an extension by using hint */
int ast_extension_state(struct ast_channel *c, const char *context, const char *exten)
{
   struct ast_exten *e;

   e = ast_hint_extension(c, context, exten);   /* Do we have a hint for this extension ? */
   if (!e)
      return -1;           /* No hint, return -1 */

   return ast_extension_state2(e);        /* Check all devices in the hint */
}

static int handle_statechange(void *datap)
{
   struct ast_hint *hint;
   struct statechange *sc = datap;

   ast_rdlock_contexts();
   AST_RWLIST_RDLOCK(&hints);

   AST_RWLIST_TRAVERSE(&hints, hint, list) {
      struct ast_state_cb *cblist;
      char buf[AST_MAX_EXTENSION];
      char *parse = buf;
      char *cur;
      int state;

      ast_copy_string(buf, ast_get_extension_app(hint->exten), sizeof(buf));
      while ( (cur = strsep(&parse, "&")) ) {
         if (!strcasecmp(cur, sc->dev))
            break;
      }
      if (!cur)
         continue;

      /* Get device state for this hint */
      state = ast_extension_state2(hint->exten);

      if ((state == -1) || (state == hint->laststate))
         continue;

      /* Device state changed since last check - notify the watchers */

      /* For general callbacks */
      AST_LIST_TRAVERSE(&statecbs, cblist, entry) {
         cblist->callback(hint->exten->parent->name, hint->exten->exten, state, cblist->data);
      }

      /* For extension callbacks */
      AST_LIST_TRAVERSE(&hint->callbacks, cblist, entry) {
         cblist->callback(hint->exten->parent->name, hint->exten->exten, state, cblist->data);
      }

      hint->laststate = state;   /* record we saw the change */
   }
   AST_RWLIST_UNLOCK(&hints);
   ast_unlock_contexts();
   ast_free(sc);
   return 0;
}

/*! \brief  Add watcher for extension states */
int ast_extension_state_add(const char *context, const char *exten,
             ast_state_cb_type callback, void *data)
{
   struct ast_hint *hint;
   struct ast_state_cb *cblist;
   struct ast_exten *e;

   /* If there's no context and extension:  add callback to statecbs list */
   if (!context && !exten) {
      AST_RWLIST_WRLOCK(&hints);

      AST_LIST_TRAVERSE(&statecbs, cblist, entry) {
         if (cblist->callback == callback) {
            cblist->data = data;
            AST_RWLIST_UNLOCK(&hints);
            return 0;
         }
      }

      /* Now insert the callback */
      if (!(cblist = ast_calloc(1, sizeof(*cblist)))) {
         AST_RWLIST_UNLOCK(&hints);
         return -1;
      }
      cblist->id = 0;
      cblist->callback = callback;
      cblist->data = data;

      AST_LIST_INSERT_HEAD(&statecbs, cblist, entry);

      AST_RWLIST_UNLOCK(&hints);

      return 0;
   }

   if (!context || !exten)
      return -1;

   /* This callback type is for only one hint, so get the hint */
   e = ast_hint_extension(NULL, context, exten);
   if (!e) {
      return -1;
   }

   /* If this is a pattern, dynamically create a new extension for this
    * particular match.  Note that this will only happen once for each
    * individual extension, because the pattern will no longer match first.
    */
   if (e->exten[0] == '_') {
      ast_add_extension(e->parent->name, 0, exten, e->priority, e->label,
         e->cidmatch, e->app, ast_strdup(e->data), ast_free_ptr,
         e->registrar);
      e = ast_hint_extension(NULL, context, exten);
      if (!e || e->exten[0] == '_') {
         return -1;
      }
   }

   /* Find the hint in the list of hints */
   AST_RWLIST_WRLOCK(&hints);

   AST_RWLIST_TRAVERSE(&hints, hint, list) {
      if (hint->exten == e)
         break;
   }

   if (!hint) {
      /* We have no hint, sorry */
      AST_RWLIST_UNLOCK(&hints);
      return -1;
   }

   /* Now insert the callback in the callback list  */
   if (!(cblist = ast_calloc(1, sizeof(*cblist)))) {
      AST_RWLIST_UNLOCK(&hints);
      return -1;
   }

   cblist->id = stateid++;    /* Unique ID for this callback */
   cblist->callback = callback;  /* Pointer to callback routine */
   cblist->data = data;    /* Data for the callback */

   AST_LIST_INSERT_HEAD(&hint->callbacks, cblist, entry);

   AST_RWLIST_UNLOCK(&hints);

   return cblist->id;
}

/*! \brief Remove a watcher from the callback list */
int ast_extension_state_del(int id, ast_state_cb_type callback)
{
   struct ast_state_cb *p_cur = NULL;
   int ret = -1;

   if (!id && !callback)
      return -1;

   AST_RWLIST_WRLOCK(&hints);

   if (!id) {  /* id == 0 is a callback without extension */
      AST_LIST_TRAVERSE_SAFE_BEGIN(&statecbs, p_cur, entry) {
         if (p_cur->callback == callback) {
            AST_LIST_REMOVE_CURRENT(entry);
            break;
         }
      }
      AST_LIST_TRAVERSE_SAFE_END;
   } else { /* callback with extension, find the callback based on ID */
      struct ast_hint *hint;
      AST_RWLIST_TRAVERSE(&hints, hint, list) {
         AST_LIST_TRAVERSE_SAFE_BEGIN(&hint->callbacks, p_cur, entry) {
            if (p_cur->id == id) {
               AST_LIST_REMOVE_CURRENT(entry);
               break;
            }
         }
         AST_LIST_TRAVERSE_SAFE_END;

         if (p_cur)
            break;
      }
   }

   if (p_cur) {
      ast_free(p_cur);
   }

   AST_RWLIST_UNLOCK(&hints);

   return ret;
}


/*! \brief Add hint to hint list, check initial extension state; the hints had better be WRLOCKED already! */
static int ast_add_hint_nolock(struct ast_exten *e)
{
   struct ast_hint *hint;

   if (!e)
      return -1;

   /* Search if hint exists, do nothing */
   AST_RWLIST_TRAVERSE(&hints, hint, list) {
      if (hint->exten == e) {
         ast_debug(2, "HINTS: Not re-adding existing hint %s: %s\n", ast_get_extension_name(e), ast_get_extension_app(e));
         return -1;
      }
   }

   ast_debug(2, "HINTS: Adding hint %s: %s\n", ast_get_extension_name(e), ast_get_extension_app(e));

   if (!(hint = ast_calloc(1, sizeof(*hint)))) {
      return -1;
   }
   /* Initialize and insert new item at the top */
   hint->exten = e;
   hint->laststate = ast_extension_state2(e);
   AST_RWLIST_INSERT_HEAD(&hints, hint, list);

   return 0;
}

/*! \brief Add hint to hint list, check initial extension state */
static int ast_add_hint(struct ast_exten *e)
{
   int ret;

   AST_RWLIST_WRLOCK(&hints);
   ret = ast_add_hint_nolock(e);
   AST_RWLIST_UNLOCK(&hints);
   
   return ret;
}

/*! \brief Change hint for an extension */
static int ast_change_hint(struct ast_exten *oe, struct ast_exten *ne)
{
   struct ast_hint *hint;
   int res = -1;

   AST_RWLIST_WRLOCK(&hints);
   AST_RWLIST_TRAVERSE(&hints, hint, list) {
      if (hint->exten == oe) {
            hint->exten = ne;
         res = 0;
         break;
      }
   }
   AST_RWLIST_UNLOCK(&hints);

   return res;
}

/*! \brief Remove hint from extension */
static int ast_remove_hint(struct ast_exten *e)
{
   /* Cleanup the Notifys if hint is removed */
   struct ast_hint *hint;
   struct ast_state_cb *cblist;
   int res = -1;

   if (!e)
      return -1;

   AST_RWLIST_TRAVERSE_SAFE_BEGIN(&hints, hint, list) {
      if (hint->exten != e)
         continue;

      while ((cblist = AST_LIST_REMOVE_HEAD(&hint->callbacks, entry))) {
         /* Notify with -1 and remove all callbacks */
         cblist->callback(hint->exten->parent->name, hint->exten->exten, 
            AST_EXTENSION_DEACTIVATED, cblist->data);
         ast_free(cblist);
      }

      AST_RWLIST_REMOVE_CURRENT(list);
      ast_free(hint);

         res = 0;

      break;
   }
   AST_RWLIST_TRAVERSE_SAFE_END;

   return res;
}


/*! \brief Get hint for channel */
int ast_get_hint(char *hint, int hintsize, char *name, int namesize, struct ast_channel *c, const char *context, const char *exten)
{
   struct ast_exten *e = ast_hint_extension(c, context, exten);

   if (e) {
      if (hint)
         ast_copy_string(hint, ast_get_extension_app(e), hintsize);
      if (name) {
         const char *tmp = ast_get_extension_app_data(e);
         if (tmp)
            ast_copy_string(name, tmp, namesize);
      }
      return -1;
   }
   return 0;
}

int ast_exists_extension(struct ast_channel *c, const char *context, const char *exten, int priority, const char *callerid)
{
   return pbx_extension_helper(c, NULL, context, exten, priority, NULL, callerid, E_MATCH, 0, 0);
}

int ast_findlabel_extension(struct ast_channel *c, const char *context, const char *exten, const char *label, const char *callerid)
{
   return pbx_extension_helper(c, NULL, context, exten, 0, label, callerid, E_FINDLABEL, 0, 0);
}

int ast_findlabel_extension2(struct ast_channel *c, struct ast_context *con, const char *exten, const char *label, const char *callerid)
{
   return pbx_extension_helper(c, con, NULL, exten, 0, label, callerid, E_FINDLABEL, 0, 0);
}

int ast_canmatch_extension(struct ast_channel *c, const char *context, const char *exten, int priority, const char *callerid)
{
   return pbx_extension_helper(c, NULL, context, exten, priority, NULL, callerid, E_CANMATCH, 0, 0);
}

int ast_matchmore_extension(struct ast_channel *c, const char *context, const char *exten, int priority, const char *callerid)
{
   return pbx_extension_helper(c, NULL, context, exten, priority, NULL, callerid, E_MATCHMORE, 0, 0);
}

int ast_spawn_extension(struct ast_channel *c, const char *context, const char *exten, int priority, const char *callerid, int *found, int combined_find_spawn)
{
   return pbx_extension_helper(c, NULL, context, exten, priority, NULL, callerid, E_SPAWN, found, combined_find_spawn);
}

/*! helper function to set extension and priority */
static void set_ext_pri(struct ast_channel *c, const char *exten, int pri)
{
   ast_channel_lock(c);
   ast_copy_string(c->exten, exten, sizeof(c->exten));
   c->priority = pri;
   ast_channel_unlock(c);
}

/*!
 * \brief collect digits from the channel into the buffer.
 * \retval 0 on timeout or done.
 * \retval -1 on error.
*/
static int collect_digits(struct ast_channel *c, int waittime, char *buf, int buflen, int pos)
{
   int digit;

   buf[pos] = '\0';  /* make sure it is properly terminated */
   while (ast_matchmore_extension(c, c->context, buf, 1, c->cid.cid_num)) {
      /* As long as we're willing to wait, and as long as it's not defined,
         keep reading digits until we can't possibly get a right answer anymore.  */
      digit = ast_waitfordigit(c, waittime);
      if (c->_softhangup == AST_SOFTHANGUP_ASYNCGOTO) {
         c->_softhangup = 0;
      } else {
         if (!digit) /* No entry */
            break;
         if (digit < 0) /* Error, maybe a  hangup */
            return -1;
         if (pos < buflen - 1) { /* XXX maybe error otherwise ? */
            buf[pos++] = digit;
            buf[pos] = '\0';
         }
         waittime = c->pbx->dtimeoutms;
      }
   }
   return 0;
}

static enum ast_pbx_result __ast_pbx_run(struct ast_channel *c, 
      struct ast_pbx_args *args)
{
   int found = 0; /* set if we find at least one match */
   int res = 0;
   int autoloopflag;
   int error = 0;    /* set an error conditions */

   /* A little initial setup here */
   if (c->pbx) {
      ast_log(LOG_WARNING, "%s already has PBX structure??\n", c->name);
      /* XXX and now what ? */
      ast_free(c->pbx);
   }
   if (!(c->pbx = ast_calloc(1, sizeof(*c->pbx))))
      return -1;
   /* Set reasonable defaults */
   c->pbx->rtimeoutms = 10000;
   c->pbx->dtimeoutms = 5000;

   autoloopflag = ast_test_flag(c, AST_FLAG_IN_AUTOLOOP);   /* save value to restore at the end */
   ast_set_flag(c, AST_FLAG_IN_AUTOLOOP);

   /* Start by trying whatever the channel is set to */
   if (!ast_exists_extension(c, c->context, c->exten, c->priority, c->cid.cid_num)) {
      /* If not successful fall back to 's' */
      ast_verb(2, "Starting %s at %s,%s,%d failed so falling back to exten 's'\n", c->name, c->context, c->exten, c->priority);
      /* XXX the original code used the existing priority in the call to
       * ast_exists_extension(), and reset it to 1 afterwards.
       * I believe the correct thing is to set it to 1 immediately.
       */
      set_ext_pri(c, "s", 1);
      if (!ast_exists_extension(c, c->context, c->exten, c->priority, c->cid.cid_num)) {
         /* JK02: And finally back to default if everything else failed */
         ast_verb(2, "Starting %s at %s,%s,%d still failed so falling back to context 'default'\n", c->name, c->context, c->exten, c->priority);
         ast_copy_string(c->context, "default", sizeof(c->context));
      }
   }
   for (;;) {
      char dst_exten[256]; /* buffer to accumulate digits */
      int pos = 0;      /* XXX should check bounds */
      int digit = 0;
      int invalid = 0;
      int timeout = 0;

      /* loop on priorities in this context/exten */
      while ( !(res = ast_spawn_extension(c, c->context, c->exten, c->priority, c->cid.cid_num, &found,1))) {
         if (c->_softhangup == AST_SOFTHANGUP_TIMEOUT && ast_exists_extension(c, c->context, "T", 1, c->cid.cid_num)) {
            set_ext_pri(c, "T", 0); /* 0 will become 1 with the c->priority++; at the end */
            /* If the AbsoluteTimeout is not reset to 0, we'll get an infinite loop */
            memset(&c->whentohangup, 0, sizeof(c->whentohangup));
            c->_softhangup &= ~AST_SOFTHANGUP_TIMEOUT;
         } else if (c->_softhangup == AST_SOFTHANGUP_TIMEOUT && ast_exists_extension(c, c->context, "e", 1, c->cid.cid_num)) {
            pbx_builtin_raise_exception(c, "ABSOLUTETIMEOUT");
            /* If the AbsoluteTimeout is not reset to 0, we'll get an infinite loop */
            memset(&c->whentohangup, 0, sizeof(c->whentohangup));
            c->_softhangup &= ~AST_SOFTHANGUP_TIMEOUT;
         } else if (c->_softhangup == AST_SOFTHANGUP_ASYNCGOTO) {
            c->_softhangup = 0;
            continue;
         } else if (ast_check_hangup(c)) {
            ast_debug(1, "Extension %s, priority %d returned normally even though call was hung up\n",
               c->exten, c->priority);
            error = 1;
            break;
         }
         c->priority++;
      } /* end while  - from here on we can use 'break' to go out */
      if (found && res) {
         /* Something bad happened, or a hangup has been requested. */
         if (strchr("0123456789ABCDEF*#", res)) {
            ast_debug(1, "Oooh, got something to jump out with ('%c')!\n", res);
            pos = 0;
            dst_exten[pos++] = digit = res;
            dst_exten[pos] = '\0';
         } else if (res == AST_PBX_INCOMPLETE) {
            ast_debug(1, "Spawn extension (%s,%s,%d) exited INCOMPLETE on '%s'\n", c->context, c->exten, c->priority, c->name);
            ast_verb(2, "Spawn extension (%s, %s, %d) exited INCOMPLETE on '%s'\n", c->context, c->exten, c->priority, c->name);

            /* Don't cycle on incomplete - this will happen if the only extension that matches is our "incomplete" extension */
            if (!ast_matchmore_extension(c, c->context, c->exten, c->priority, c->cid.cid_num)) {
               invalid = 1;
            } else {
               ast_copy_string(dst_exten, c->exten, sizeof(dst_exten));
               digit = 1;
               pos = strlen(dst_exten);
            }
         } else {
            ast_debug(1, "Spawn extension (%s,%s,%d) exited non-zero on '%s'\n", c->context, c->exten, c->priority, c->name);
            ast_verb(2, "Spawn extension (%s, %s, %d) exited non-zero on '%s'\n", c->context, c->exten, c->priority, c->name);
            
            if ((res == AST_PBX_ERROR) && ast_exists_extension(c, c->context, "e", 1, c->cid.cid_num)) {
               /* if we are already on the 'e' exten, don't jump to it again */
               if (!strcmp(c->exten, "e")) {
                  ast_verb(2, "Spawn extension (%s, %s, %d) exited ERROR while already on 'e' exten on '%s'\n", c->context, c->exten, c->priority, c->name);
                  error = 1;
               } else {
                  pbx_builtin_raise_exception(c, "ERROR");
                  continue;
               }
            }
            
            if (c->_softhangup == AST_SOFTHANGUP_ASYNCGOTO) {
               c->_softhangup = 0;
               continue;
            } else if (c->_softhangup == AST_SOFTHANGUP_TIMEOUT && ast_exists_extension(c, c->context, "T", 1, c->cid.cid_num)) {
               set_ext_pri(c, "T", 1); 
               /* If the AbsoluteTimeout is not reset to 0, we'll get an infinite loop */
               memset(&c->whentohangup, 0, sizeof(c->whentohangup));
               c->_softhangup &= ~AST_SOFTHANGUP_TIMEOUT;
               continue;
            } else {
               if (c->cdr)
                  ast_cdr_update(c);
               error = 1;
               break;
            }
         }
      }
      if (error)
         break;

      /*!\note
       * We get here on a failure of some kind:  non-existing extension or
       * hangup.  We have options, here.  We can either catch the failure
       * and continue, or we can drop out entirely. */

      if (invalid || !ast_exists_extension(c, c->context, c->exten, 1, c->cid.cid_num)) {
         /*!\note
          * If there is no match at priority 1, it is not a valid extension anymore.
          * Try to continue at "i" (for invalid) or "e" (for exception) or exit if
          * neither exist.
          */
         if (ast_exists_extension(c, c->context, "i", 1, c->cid.cid_num)) {
            ast_verb(3, "Sent into invalid extension '%s' in context '%s' on %s\n", c->exten, c->context, c->name);
            pbx_builtin_setvar_helper(c, "INVALID_EXTEN", c->exten);
            set_ext_pri(c, "i", 1);
         } else if (ast_exists_extension(c, c->context, "e", 1, c->cid.cid_num)) {
            pbx_builtin_raise_exception(c, "INVALID");
         } else {
            ast_log(LOG_WARNING, "Channel '%s' sent into invalid extension '%s' in context '%s', but no invalid handler\n",
               c->name, c->exten, c->context);
            error = 1; /* we know what to do with it */
            break;
         }
      } else if (c->_softhangup == AST_SOFTHANGUP_TIMEOUT) {
         /* If we get this far with AST_SOFTHANGUP_TIMEOUT, then we know that the "T" extension is next. */
         c->_softhangup = 0;
      } else { /* keypress received, get more digits for a full extension */
         int waittime = 0;
         if (digit)
            waittime = c->pbx->dtimeoutms;
         else if (!autofallthrough)
            waittime = c->pbx->rtimeoutms;
         if (!waittime) {
            const char *status = pbx_builtin_getvar_helper(c, "DIALSTATUS");
            if (!status)
               status = "UNKNOWN";
            ast_verb(3, "Auto fallthrough, channel '%s' status is '%s'\n", c->name, status);
            if (!strcasecmp(status, "CONGESTION"))
               res = pbx_builtin_congestion(c, "10");
            else if (!strcasecmp(status, "CHANUNAVAIL"))
               res = pbx_builtin_congestion(c, "10");
            else if (!strcasecmp(status, "BUSY"))
               res = pbx_builtin_busy(c, "10");
            error = 1; /* XXX disable message */
            break;   /* exit from the 'for' loop */
         }

         if (collect_digits(c, waittime, dst_exten, sizeof(dst_exten), pos))
            break;
         if (res == AST_PBX_INCOMPLETE && ast_strlen_zero(&dst_exten[pos]))
            timeout = 1;
         if (!timeout && ast_exists_extension(c, c->context, dst_exten, 1, c->cid.cid_num)) /* Prepare the next cycle */
            set_ext_pri(c, dst_exten, 1);
         else {
            /* No such extension */
            if (!timeout && !ast_strlen_zero(dst_exten)) {
               /* An invalid extension */
               if (ast_exists_extension(c, c->context, "i", 1, c->cid.cid_num)) {
                  ast_verb(3, "Invalid extension '%s' in context '%s' on %s\n", dst_exten, c->context, c->name);
                  pbx_builtin_setvar_helper(c, "INVALID_EXTEN", dst_exten);
                  set_ext_pri(c, "i", 1);
               } else if (ast_exists_extension(c, c->context, "e", 1, c->cid.cid_num)) {
                  pbx_builtin_raise_exception(c, "INVALID");
               } else {
                  ast_log(LOG_WARNING, "Invalid extension '%s', but no rule 'i' in context '%s'\n", dst_exten, c->context);
                  found = 1; /* XXX disable message */
                  break;
               }
            } else {
               /* A simple timeout */
               if (ast_exists_extension(c, c->context, "t", 1, c->cid.cid_num)) {
                  ast_verb(3, "Timeout on %s\n", c->name);
                  set_ext_pri(c, "t", 1);
               } else if (ast_exists_extension(c, c->context, "e", 1, c->cid.cid_num)) {
                  pbx_builtin_raise_exception(c, "RESPONSETIMEOUT");
               } else {
                  ast_log(LOG_WARNING, "Timeout, but no rule 't' in context '%s'\n", c->context);
                  found = 1; /* XXX disable message */
                  break;
               }
            }
         }
         if (c->cdr) {
            ast_verb(2, "CDR updated on %s\n",c->name);
            ast_cdr_update(c);
         }
      }
   }

   if (!found && !error) {
      ast_log(LOG_WARNING, "Don't know what to do with '%s'\n", c->name);
   }

   if (!args || !args->no_hangup_chan) {
      ast_softhangup(c, c->hangupcause ? c->hangupcause : AST_CAUSE_NORMAL_CLEARING);
   }

   if ((!args || !args->no_hangup_chan) &&
         !ast_test_flag(c, AST_FLAG_BRIDGE_HANGUP_RUN) && 
         ast_exists_extension(c, c->context, "h", 1, c->cid.cid_num)) {
      set_ext_pri(c, "h", 1);
      if (c->cdr && ast_opt_end_cdr_before_h_exten) {
         ast_cdr_end(c->cdr);
      }
      while ((res = ast_spawn_extension(c, c->context, c->exten, c->priority, c->cid.cid_num, &found, 1)) == 0) {
         c->priority++;
      }
      if (found && res) {
         /* Something bad happened, or a hangup has been requested. */
         ast_debug(1, "Spawn extension (%s,%s,%d) exited non-zero on '%s'\n", c->context, c->exten, c->priority, c->name);
         ast_verb(2, "Spawn extension (%s, %s, %d) exited non-zero on '%s'\n", c->context, c->exten, c->priority, c->name);
      }
   }
   ast_set2_flag(c, autoloopflag, AST_FLAG_IN_AUTOLOOP);
   ast_clear_flag(c, AST_FLAG_BRIDGE_HANGUP_RUN); /* from one round to the next, make sure this gets cleared */
   pbx_destroy(c->pbx);
   c->pbx = NULL;

   if (!args || !args->no_hangup_chan) {
      ast_hangup(c);
   }

   return 0;
}

/*! 
 * \brief Increase call count for channel
 * \retval 0 on success
 * \retval non-zero if a configured limit (maxcalls, maxload, minmemfree) was reached 
*/
static int increase_call_count(const struct ast_channel *c)
{
   int failed = 0;
   double curloadavg;
#if defined(HAVE_SYSINFO)
   long curfreemem;
   struct sysinfo sys_info;
#endif

   ast_mutex_lock(&maxcalllock);
   if (option_maxcalls) {
      if (countcalls >= option_maxcalls) {
         ast_log(LOG_WARNING, "Maximum call limit of %d calls exceeded by '%s'!\n", option_maxcalls, c->name);
         failed = -1;
      }
   }
   if (option_maxload) {
      getloadavg(&curloadavg, 1);
      if (curloadavg >= option_maxload) {
         ast_log(LOG_WARNING, "Maximum loadavg limit of %f load exceeded by '%s' (currently %f)!\n", option_maxload, c->name, curloadavg);
         failed = -1;
      }
   }
#if defined(HAVE_SYSINFO)
   if (option_minmemfree) {
      if (!sysinfo(&sys_info)) {
         /* make sure that the free system memory is above the configured low watermark
          * convert the amount of freeram from mem_units to MB */
         curfreemem = sys_info.freeram / sys_info.mem_unit; 
         curfreemem /= 1024*1024; 
         if (curfreemem < option_minmemfree) {
            ast_log(LOG_WARNING, "Available system memory (~%ldMB) is below the configured low watermark (%ldMB)\n", curfreemem, option_minmemfree);
            failed = -1;
         }
      }
   }
#endif
      
   if (!failed) {
      countcalls++;
      totalcalls++;
   }
   ast_mutex_unlock(&maxcalllock);

   return failed;
}

static void decrease_call_count(void)
{
   ast_mutex_lock(&maxcalllock);
   if (countcalls > 0)
      countcalls--;
   ast_mutex_unlock(&maxcalllock);
}

static void destroy_exten(struct ast_exten *e)
{
   if (e->priority == PRIORITY_HINT)
      ast_remove_hint(e);

   if (e->peer_table)
      ast_hashtab_destroy(e->peer_table,0);
   if (e->peer_label_table)
      ast_hashtab_destroy(e->peer_label_table, 0);
   if (e->datad)
      e->datad(e->data);
   ast_free(e);
}

static void *pbx_thread(void *data)
{
   /* Oh joyeous kernel, we're a new thread, with nothing to do but
      answer this channel and get it going.
   */
   /* NOTE:
      The launcher of this function _MUST_ increment 'countcalls'
      before invoking the function; it will be decremented when the
      PBX has finished running on the channel
    */
   struct ast_channel *c = data;

   __ast_pbx_run(c, NULL);
   decrease_call_count();

   pthread_exit(NULL);

   return NULL;
}

enum ast_pbx_result ast_pbx_start(struct ast_channel *c)
{
   pthread_t t;

   if (!c) {
      ast_log(LOG_WARNING, "Asked to start thread on NULL channel?\n");
      return AST_PBX_FAILED;
   }

   if (increase_call_count(c))
      return AST_PBX_CALL_LIMIT;

   /* Start a new thread, and get something handling this channel. */
   if (ast_pthread_create_detached(&t, NULL, pbx_thread, c)) {
      ast_log(LOG_WARNING, "Failed to create new channel thread\n");
      decrease_call_count();
      return AST_PBX_FAILED;
   }

   return AST_PBX_SUCCESS;
}

enum ast_pbx_result ast_pbx_run_args(struct ast_channel *c, struct ast_pbx_args *args)
{
   enum ast_pbx_result res = AST_PBX_SUCCESS;

   if (increase_call_count(c)) {
      return AST_PBX_CALL_LIMIT;
   }

   res = __ast_pbx_run(c, args);

   decrease_call_count();

   return res;
}

enum ast_pbx_result ast_pbx_run(struct ast_channel *c)
{
   return ast_pbx_run_args(c, NULL);
}

int ast_active_calls(void)
{
   return countcalls;
}

int ast_processed_calls(void)
{
   return totalcalls;
}

int pbx_set_autofallthrough(int newval)
{
   int oldval = autofallthrough;
   autofallthrough = newval;
   return oldval;
}

int pbx_set_extenpatternmatchnew(int newval)
{
   int oldval = extenpatternmatchnew;
   extenpatternmatchnew = newval;
   return oldval;
}

void pbx_set_overrideswitch(const char *newval)
{
   if (overrideswitch) {
      ast_free(overrideswitch);
   }
   if (!ast_strlen_zero(newval)) {
      overrideswitch = ast_strdup(newval);
   } else {
      overrideswitch = NULL;
   }
}

/*!
 * \brief lookup for a context with a given name,
 * \retval found context or NULL if not found.
*/
static struct ast_context *find_context(const char *context)
{
   struct ast_context *c = NULL;
   struct fake_context item;

   ast_copy_string(item.name, context, sizeof(item.name));

   c = ast_hashtab_lookup(contexts_table,&item);

   return c;
}

/*!
 * \brief lookup for a context with a given name,
 * \retval with conlock held if found.
 * \retval NULL if not found.
*/
static struct ast_context *find_context_locked(const char *context)
{
   struct ast_context *c = NULL;
   struct fake_context item;

   ast_copy_string(item.name, context, sizeof(item.name));

   ast_rdlock_contexts();
   c = ast_hashtab_lookup(contexts_table,&item);

#ifdef NOTNOW

   while ( (c = ast_walk_contexts(c)) ) {
      if (!strcmp(ast_get_context_name(c), context))
         return c;
   }
#endif
   if (!c)
      ast_unlock_contexts();

   return c;
}

/*!
 * \brief Remove included contexts.
 * This function locks contexts list by &conlist, search for the right context
 * structure, leave context list locked and call ast_context_remove_include2
 * which removes include, unlock contexts list and return ...
*/
int ast_context_remove_include(const char *context, const char *include, const char *registrar)
{
   int ret = -1;
   struct ast_context *c = find_context_locked(context);

   if (c) {
      /* found, remove include from this context ... */
      ret = ast_context_remove_include2(c, include, registrar);
      ast_unlock_contexts();
   }
   return ret;
}

/*!
 * \brief Locks context, remove included contexts, unlocks context.
 * When we call this function, &conlock lock must be locked, because when
 * we giving *con argument, some process can remove/change this context
 * and after that there can be segfault.
 *
 * \retval 0 on success.
 * \retval -1 on failure.
 */
int ast_context_remove_include2(struct ast_context *con, const char *include, const char *registrar)
{
   struct ast_include *i, *pi = NULL;
   int ret = -1;

   ast_wrlock_context(con);

   /* find our include */
   for (i = con->includes; i; pi = i, i = i->next) {
      if (!strcmp(i->name, include) &&
            (!registrar || !strcmp(i->registrar, registrar))) {
         /* remove from list */
         ast_verb(3, "Removing inclusion of context '%s' in context '%s; registrar=%s'\n", include, ast_get_context_name(con), registrar);
         if (pi)
            pi->next = i->next;
         else
            con->includes = i->next;
         /* free include and return */
         ast_free(i);
         ret = 0;
         break;
      }
   }

   ast_unlock_context(con);

   return ret;
}

/*!
 * \note This function locks contexts list by &conlist, search for the rigt context
 * structure, leave context list locked and call ast_context_remove_switch2
 * which removes switch, unlock contexts list and return ...
 */
int ast_context_remove_switch(const char *context, const char *sw, const char *data, const char *registrar)
{
   int ret = -1; /* default error return */
   struct ast_context *c = find_context_locked(context);

   if (c) {
      /* remove switch from this context ... */
      ret = ast_context_remove_switch2(c, sw, data, registrar);
      ast_unlock_contexts();
   }
   return ret;
}

/*!
 * \brief This function locks given context, removes switch, unlock context and
 * return.
 * \note When we call this function, &conlock lock must be locked, because when
 * we giving *con argument, some process can remove/change this context
 * and after that there can be segfault.
 *
 */
int ast_context_remove_switch2(struct ast_context *con, const char *sw, const char *data, const char *registrar)
{
   struct ast_sw *i;
   int ret = -1;

   ast_wrlock_context(con);

   /* walk switches */
   AST_LIST_TRAVERSE_SAFE_BEGIN(&con->alts, i, list) {
      if (!strcmp(i->name, sw) && !strcmp(i->data, data) &&
         (!registrar || !strcmp(i->registrar, registrar))) {
         /* found, remove from list */
         ast_verb(3, "Removing switch '%s' from context '%s; registrar=%s'\n", sw, ast_get_context_name(con), registrar);
         AST_LIST_REMOVE_CURRENT(list);
         ast_free(i); /* free switch and return */
         ret = 0;
         break;
      }
   }
   AST_LIST_TRAVERSE_SAFE_END;

   ast_unlock_context(con);

   return ret;
}

/*
 * \note This functions lock contexts list, search for the right context,
 * call ast_context_remove_extension2, unlock contexts list and return.
 * In this function we are using
 */
int ast_context_remove_extension(const char *context, const char *extension, int priority, const char *registrar)
{
   return ast_context_remove_extension_callerid(context, extension, priority, NULL, 0, registrar);
}

int ast_context_remove_extension_callerid(const char *context, const char *extension, int priority, const char *callerid, int matchcallerid, const char *registrar)
{
   int ret = -1; /* default error return */
   struct ast_context *c = find_context_locked(context);

   if (c) { /* ... remove extension ... */
      ret = ast_context_remove_extension_callerid2(c, extension, priority, callerid, matchcallerid, registrar, 1);
      ast_unlock_contexts();
   }
   return ret;
}

/*!
 * \brief This functionc locks given context, search for the right extension and
 * fires out all peer in this extensions with given priority. If priority
 * is set to 0, all peers are removed. After that, unlock context and
 * return.
 * \note When do you want to call this function, make sure that &conlock is locked,
 * because some process can handle with your *con context before you lock
 * it.
 *
 */
int ast_context_remove_extension2(struct ast_context *con, const char *extension, int priority, const char *registrar, int already_locked)
{
   return ast_context_remove_extension_callerid2(con, extension, priority, NULL, 0, registrar, already_locked);
}

int ast_context_remove_extension_callerid2(struct ast_context *con, const char *extension, int priority, const char *callerid, int matchcallerid, const char *registrar, int already_locked)
{
   struct ast_exten *exten, *prev_exten = NULL;
   struct ast_exten *peer;
   struct ast_exten ex, *exten2, *exten3;
   char dummy_name[1024];
   struct ast_exten *previous_peer = NULL;
   struct ast_exten *next_peer = NULL;
   int found = 0;

   if (!already_locked)
      ast_wrlock_context(con);

   /* Handle this is in the new world */

   /* FIXME For backwards compatibility, if callerid==NULL, then remove ALL
    * peers, not just those matching the callerid. */
#ifdef NEED_DEBUG
   ast_verb(3,"Removing %s/%s/%d%s%s from trees, registrar=%s\n", con->name, extension, priority, matchcallerid ? "/" : "", matchcallerid ? callerid : "", registrar);
#endif
#ifdef CONTEXT_DEBUG
   check_contexts(__FILE__, __LINE__);
#endif
   /* find this particular extension */
   ex.exten = dummy_name;
   ex.matchcid = matchcallerid && !ast_strlen_zero(callerid); /* don't say match if there's no callerid */
   ex.cidmatch = callerid;
   ast_copy_string(dummy_name, extension, sizeof(dummy_name));
   exten = ast_hashtab_lookup(con->root_table, &ex);
   if (exten) {
      if (priority == 0) {
         exten2 = ast_hashtab_remove_this_object(con->root_table, exten);
         if (!exten2)
            ast_log(LOG_ERROR,"Trying to delete the exten %s from context %s, but could not remove from the root_table\n", extension, con->name);
         if (con->pattern_tree) {
            
            struct match_char *x = add_exten_to_pattern_tree(con, exten, 1);
            
            if (x->exten) { /* this test for safety purposes */
               x->deleted = 1; /* with this marked as deleted, it will never show up in the scoreboard, and therefore never be found */
               x->exten = 0; /* get rid of what will become a bad pointer */
            } else {
               ast_log(LOG_WARNING,"Trying to delete an exten from a context, but the pattern tree node returned isn't a full extension\n");
            }
         }
      } else {
         ex.priority = priority;
         exten2 = ast_hashtab_lookup(exten->peer_table, &ex);
         if (exten2) {
            
            if (exten2->label) { /* if this exten has a label, remove that, too */
               exten3 = ast_hashtab_remove_this_object(exten->peer_label_table,exten2);
               if (!exten3)
                  ast_log(LOG_ERROR,"Did not remove this priority label (%d/%s) from the peer_label_table of context %s, extension %s!\n", priority, exten2->label, con->name, exten2->exten);
            }
         
            exten3 = ast_hashtab_remove_this_object(exten->peer_table, exten2);
            if (!exten3)
               ast_log(LOG_ERROR,"Did not remove this priority (%d) from the peer_table of context %s, extension %s!\n", priority, con->name, exten2->exten);
            if (exten2 == exten && exten2->peer) {
               exten2 = ast_hashtab_remove_this_object(con->root_table, exten);
               ast_hashtab_insert_immediate(con->root_table, exten2->peer);
            }
            if (ast_hashtab_size(exten->peer_table) == 0) {
               /* well, if the last priority of an exten is to be removed,
                  then, the extension is removed, too! */
               exten3 = ast_hashtab_remove_this_object(con->root_table, exten);
               if (!exten3)
                  ast_log(LOG_ERROR,"Did not remove this exten (%s) from the context root_table (%s) (priority %d)\n", exten->exten, con->name, priority);
               if (con->pattern_tree) {
                  struct match_char *x = add_exten_to_pattern_tree(con, exten, 1);
                  if (x->exten) { /* this test for safety purposes */
                     x->deleted = 1; /* with this marked as deleted, it will never show up in the scoreboard, and therefore never be found */
                     x->exten = 0; /* get rid of what will become a bad pointer */
                  }
               }
            }
         } else {
            ast_log(LOG_ERROR,"Could not find priority %d of exten %s in context %s!\n",
                  priority, exten->exten, con->name);
         }
      }
   } else {
      /* hmmm? this exten is not in this pattern tree? */
      ast_log(LOG_WARNING,"Cannot find extension %s in root_table in context %s\n",
            extension, con->name);
   }
#ifdef NEED_DEBUG
   if (con->pattern_tree) {
      ast_log(LOG_NOTICE,"match char tree after exten removal:\n");
      log_match_char_tree(con->pattern_tree, " ");
   }
#endif

   /* scan the extension list to find first matching extension-registrar */
   for (exten = con->root; exten; prev_exten = exten, exten = exten->next) {
      if (!strcmp(exten->exten, extension) &&
         (!registrar || !strcmp(exten->registrar, registrar)) &&
         (!matchcallerid || (!ast_strlen_zero(callerid) && !ast_strlen_zero(exten->cidmatch) && !strcmp(exten->cidmatch, callerid)) || (ast_strlen_zero(callerid) && ast_strlen_zero(exten->cidmatch))))
         break;
   }
   if (!exten) {
      /* we can't find right extension */
      if (!already_locked)
         ast_unlock_context(con);
      return -1;
   }

   /* scan the priority list to remove extension with exten->priority == priority */
   for (peer = exten, next_peer = exten->peer ? exten->peer : exten->next;
       peer && !strcmp(peer->exten, extension) && (!matchcallerid || (!ast_strlen_zero(callerid) && !ast_strlen_zero(peer->cidmatch) && !strcmp(peer->cidmatch,callerid)) || (ast_strlen_zero(callerid) && ast_strlen_zero(peer->cidmatch)));
         peer = next_peer, next_peer = next_peer ? (next_peer->peer ? next_peer->peer : next_peer->next) : NULL) {
      if ((priority == 0 || peer->priority == priority) &&
            (!callerid || !matchcallerid || (matchcallerid && !strcmp(peer->cidmatch, callerid))) &&
            (!registrar || !strcmp(peer->registrar, registrar) )) {
         found = 1;

         /* we are first priority extension? */
         if (!previous_peer) {
            /*
             * We are first in the priority chain, so must update the extension chain.
             * The next node is either the next priority or the next extension
             */
            struct ast_exten *next_node = peer->peer ? peer->peer : peer->next;
            if (peer->peer) {
               /* move the peer_table and peer_label_table down to the next peer, if
                  it is there */
               peer->peer->peer_table = peer->peer_table;
               peer->peer->peer_label_table = peer->peer_label_table;
               peer->peer_table = NULL;
               peer->peer_label_table = NULL;
            }
            if (!prev_exten) {   /* change the root... */
               con->root = next_node;
            } else {
               prev_exten->next = next_node; /* unlink */
            }
            if (peer->peer)   { /* update the new head of the pri list */
               peer->peer->next = peer->next;
            }
         } else { /* easy, we are not first priority in extension */
            previous_peer->peer = peer->peer;
         }

         /* now, free whole priority extension */
         destroy_exten(peer);
      } else {
         previous_peer = peer;
      }
   }
   if (!already_locked)
      ast_unlock_context(con);
   return found ? 0 : -1;
}


/*!
 * \note This function locks contexts list by &conlist, searches for the right context
 * structure, and locks the macrolock mutex in that context.
 * macrolock is used to limit a macro to be executed by one call at a time.
 */
int ast_context_lockmacro(const char *context)
{
   struct ast_context *c = NULL;
   int ret = -1;
   struct fake_context item;

   ast_rdlock_contexts();

   ast_copy_string(item.name, context, sizeof(item.name));

   c = ast_hashtab_lookup(contexts_table,&item);
   if (c)
      ret = 0;


#ifdef NOTNOW

   while ((c = ast_walk_contexts(c))) {
      if (!strcmp(ast_get_context_name(c), context)) {
         ret = 0;
         break;
      }
   }

#endif
   ast_unlock_contexts();

   /* if we found context, lock macrolock */
   if (ret == 0) 
      ret = ast_mutex_lock(&c->macrolock);

   return ret;
}

/*!
 * \note This function locks contexts list by &conlist, searches for the right context
 * structure, and unlocks the macrolock mutex in that context.
 * macrolock is used to limit a macro to be executed by one call at a time.
 */
int ast_context_unlockmacro(const char *context)
{
   struct ast_context *c = NULL;
   int ret = -1;
   struct fake_context item;

   ast_rdlock_contexts();

   ast_copy_string(item.name, context, sizeof(item.name));

   c = ast_hashtab_lookup(contexts_table,&item);
   if (c)
      ret = 0;
#ifdef NOTNOW

   while ((c = ast_walk_contexts(c))) {
      if (!strcmp(ast_get_context_name(c), context)) {
         ret = 0;
         break;
      }
   }

#endif
   ast_unlock_contexts();

   /* if we found context, unlock macrolock */
   if (ret == 0) 
      ret = ast_mutex_unlock(&c->macrolock);

   return ret;
}

/*! \brief Dynamically register a new dial plan application */
int ast_register_application2(const char *app, int (*execute)(struct ast_channel *, void *), const char *synopsis, const char *description, void *mod)
{
   struct ast_app *tmp, *cur = NULL;
   char tmps[80];
   int length, res;

   AST_RWLIST_WRLOCK(&apps);
   AST_RWLIST_TRAVERSE(&apps, tmp, list) {
      if (!(res = strcasecmp(app, tmp->name))) {
         ast_log(LOG_WARNING, "Already have an application '%s'\n", app);
         AST_RWLIST_UNLOCK(&apps);
         return -1;
      } else if (res < 0)
         break;
   }

   length = sizeof(*tmp) + strlen(app) + 1;

   if (!(tmp = ast_calloc(1, length))) {
      AST_RWLIST_UNLOCK(&apps);
      return -1;
   }

   strcpy(tmp->name, app);
   tmp->execute = execute;
   tmp->synopsis = synopsis;
   tmp->description = description;
   tmp->module = mod;

   /* Store in alphabetical order */
   AST_RWLIST_TRAVERSE_SAFE_BEGIN(&apps, cur, list) {
      if (strcasecmp(tmp->name, cur->name) < 0) {
         AST_RWLIST_INSERT_BEFORE_CURRENT(tmp, list);
         break;
      }
   }
   AST_RWLIST_TRAVERSE_SAFE_END;
   if (!cur)
      AST_RWLIST_INSERT_TAIL(&apps, tmp, list);

   ast_verb(2, "Registered application '%s'\n", term_color(tmps, tmp->name, COLOR_BRCYAN, 0, sizeof(tmps)));

   AST_RWLIST_UNLOCK(&apps);

   return 0;
}

/*
 * Append to the list. We don't have a tail pointer because we need
 * to scan the list anyways to check for duplicates during insertion.
 */
int ast_register_switch(struct ast_switch *sw)
{
   struct ast_switch *tmp;

   AST_RWLIST_WRLOCK(&switches);
   AST_RWLIST_TRAVERSE(&switches, tmp, list) {
      if (!strcasecmp(tmp->name, sw->name)) {
         AST_RWLIST_UNLOCK(&switches);
         ast_log(LOG_WARNING, "Switch '%s' already found\n", sw->name);
         return -1;
      }
   }
   AST_RWLIST_INSERT_TAIL(&switches, sw, list);
   AST_RWLIST_UNLOCK(&switches);

   return 0;
}

void ast_unregister_switch(struct ast_switch *sw)
{
   AST_RWLIST_WRLOCK(&switches);
   AST_RWLIST_REMOVE(&switches, sw, list);
   AST_RWLIST_UNLOCK(&switches);
}

/*
 * Help for CLI commands ...
 */

/*
 * \brief 'show application' CLI command implementation function...
 */
static char *handle_show_application(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   struct ast_app *aa;
   int app, no_registered_app = 1;
   char *ret = NULL;
   int which = 0;
   int wordlen;

   switch (cmd) {
   case CLI_INIT: 
      e->command = "core show application";
      e->usage = 
         "Usage: core show application <application> [<application> [<application> [...]]]\n"
         "       Describes a particular application.\n";
      return NULL;
   case CLI_GENERATE:
      /*
       * There is a possibility to show informations about more than one
       * application at one time. You can type 'show application Dial Echo' and
       * you will see informations about these two applications ...
       */
      wordlen = strlen(a->word);
      /* return the n-th [partial] matching entry */
      AST_RWLIST_RDLOCK(&apps);
      AST_RWLIST_TRAVERSE(&apps, aa, list) {
         if (!strncasecmp(a->word, aa->name, wordlen) && ++which > a->n) {
            ret = ast_strdup(aa->name);
            break;
         }
      }
      AST_RWLIST_UNLOCK(&apps);

      return ret;
   }

   if (a->argc < 4)
      return CLI_SHOWUSAGE;

   /* ... go through all applications ... */
   AST_RWLIST_RDLOCK(&apps);
   AST_RWLIST_TRAVERSE(&apps, aa, list) {
      /* ... compare this application name with all arguments given
       * to 'show application' command ... */
      for (app = 3; app < a->argc; app++) {
         if (!strcasecmp(aa->name, a->argv[app])) {
            /* Maximum number of characters added by terminal coloring is 22 */
            char infotitle[64 + AST_MAX_APP + 22], syntitle[40], destitle[40];
            char info[64 + AST_MAX_APP], *synopsis = NULL, *description = NULL;
            int synopsis_size, description_size;

            no_registered_app = 0;

            if (aa->synopsis)
               synopsis_size = strlen(aa->synopsis) + 23;
            else
               synopsis_size = strlen("Not available") + 23;
            synopsis = alloca(synopsis_size);

            if (aa->description)
               description_size = strlen(aa->description) + 23;
            else
               description_size = strlen("Not available") + 23;
            description = alloca(description_size);

            if (synopsis && description) {
               snprintf(info, 64 + AST_MAX_APP, "\n  -= Info about application '%s' =- \n\n", aa->name);
               term_color(infotitle, info, COLOR_MAGENTA, 0, 64 + AST_MAX_APP + 22);
               term_color(syntitle, "[Synopsis]\n", COLOR_MAGENTA, 0, 40);
               term_color(destitle, "[Description]\n", COLOR_MAGENTA, 0, 40);
               term_color(synopsis,
                           aa->synopsis ? aa->synopsis : "Not available",
                           COLOR_CYAN, 0, synopsis_size);
               term_color(description,
                           aa->description ? aa->description : "Not available",
                           COLOR_CYAN, 0, description_size);

               ast_cli(a->fd,"%s%s%s\n\n%s%s\n", infotitle, syntitle, synopsis, destitle, description);
            } else {
               /* ... one of our applications, show info ...*/
               ast_cli(a->fd,"\n  -= Info about application '%s' =- \n\n"
                  "[Synopsis]\n  %s\n\n"
                  "[Description]\n%s\n",
                  aa->name,
                  aa->synopsis ? aa->synopsis : "Not available",
                  aa->description ? aa->description : "Not available");
            }
         }
      }
   }
   AST_RWLIST_UNLOCK(&apps);

   /* we found at least one app? no? */
   if (no_registered_app) {
      ast_cli(a->fd, "Your application(s) is (are) not registered\n");
      return CLI_FAILURE;
   }

   return CLI_SUCCESS;
}

/*! \brief  handle_show_hints: CLI support for listing registered dial plan hints */
static char *handle_show_hints(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   struct ast_hint *hint;
   int num = 0;
   int watchers;
   struct ast_state_cb *watcher;

   switch (cmd) {
   case CLI_INIT:
      e->command = "core show hints";
      e->usage = 
         "Usage: core show hints\n"
         "       List registered hints\n";
      return NULL;
   case CLI_GENERATE:
      return NULL;   
   }

   AST_RWLIST_RDLOCK(&hints);
   if (AST_RWLIST_EMPTY(&hints)) {
      ast_cli(a->fd, "There are no registered dialplan hints\n");
      AST_RWLIST_UNLOCK(&hints);
      return CLI_SUCCESS;
   }
   /* ... we have hints ... */
   ast_cli(a->fd, "\n    -= Registered Asterisk Dial Plan Hints =-\n");
   AST_RWLIST_TRAVERSE(&hints, hint, list) {
      watchers = 0;
      AST_LIST_TRAVERSE(&hint->callbacks, watcher, entry) {
         watchers++;
      }
      ast_cli(a->fd, "   %20s@%-20.20s: %-20.20s  State:%-15.15s Watchers %2d\n",
         ast_get_extension_name(hint->exten),
         ast_get_context_name(ast_get_extension_context(hint->exten)),
         ast_get_extension_app(hint->exten),
         ast_extension_state2str(hint->laststate), watchers);
      num++;
   }
   ast_cli(a->fd, "----------------\n");
   ast_cli(a->fd, "- %d hints registered\n", num);
   AST_RWLIST_UNLOCK(&hints);
   return CLI_SUCCESS;
}

/*! \brief autocomplete for CLI command 'core show hint' */
static char *complete_core_show_hint(const char *line, const char *word, int pos, int state)
{
   struct ast_hint *hint;
   char *ret = NULL;
   int which = 0;
   int wordlen;

   if (pos != 3)
      return NULL;
   
   wordlen = strlen(word);

   AST_RWLIST_RDLOCK(&hints);
   /* walk through all hints */
   AST_RWLIST_TRAVERSE(&hints, hint, list) {
      if (!strncasecmp(word, ast_get_extension_name(hint->exten), wordlen) && ++which > state) {
         ret = ast_strdup(ast_get_extension_name(hint->exten));
         break;
      }
   }
   AST_RWLIST_UNLOCK(&hints);

   return ret;
}

/*! \brief  handle_show_hint: CLI support for listing registered dial plan hint */
static char *handle_show_hint(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   struct ast_hint *hint;
   int watchers;
   int num = 0, extenlen;
   struct ast_state_cb *watcher;

   switch (cmd) {
   case CLI_INIT:
      e->command = "core show hint";
      e->usage =
         "Usage: core show hint <exten>\n"
         "       List registered hint\n";
      return NULL;
   case CLI_GENERATE:
      return complete_core_show_hint(a->line, a->word, a->pos, a->n);
   }

   if (a->argc < 4)
      return CLI_SHOWUSAGE;

   AST_RWLIST_RDLOCK(&hints);
   if (AST_RWLIST_EMPTY(&hints)) {
      ast_cli(a->fd, "There are no registered dialplan hints\n");
      AST_RWLIST_UNLOCK(&hints);
      return CLI_SUCCESS;
   }
   extenlen = strlen(a->argv[3]);
   AST_RWLIST_TRAVERSE(&hints, hint, list) {
      if (!strncasecmp(ast_get_extension_name(hint->exten), a->argv[3], extenlen)) {
         watchers = 0;
         AST_LIST_TRAVERSE(&hint->callbacks, watcher, entry) {
            watchers++;
         }
         ast_cli(a->fd, "   %20s@%-20.20s: %-20.20s  State:%-15.15s Watchers %2d\n",
            ast_get_extension_name(hint->exten),
            ast_get_context_name(ast_get_extension_context(hint->exten)),
            ast_get_extension_app(hint->exten),
            ast_extension_state2str(hint->laststate), watchers);
         num++;
      }
   }
   AST_RWLIST_UNLOCK(&hints);
   if (!num)
      ast_cli(a->fd, "No hints matching extension %s\n", a->argv[3]);
   else
      ast_cli(a->fd, "%d hint%s matching extension %s\n", num, (num!=1 ? "s":""), a->argv[3]);
   return CLI_SUCCESS;
}


/*! \brief  handle_show_switches: CLI support for listing registered dial plan switches */
static char *handle_show_switches(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   struct ast_switch *sw;

   switch (cmd) {
   case CLI_INIT:
      e->command = "core show switches";
      e->usage = 
         "Usage: core show switches\n"
         "       List registered switches\n";
      return NULL;
   case CLI_GENERATE:
      return NULL;   
   }

   AST_RWLIST_RDLOCK(&switches);

   if (AST_RWLIST_EMPTY(&switches)) {
      AST_RWLIST_UNLOCK(&switches);
      ast_cli(a->fd, "There are no registered alternative switches\n");
      return CLI_SUCCESS;
   }

   ast_cli(a->fd, "\n    -= Registered Asterisk Alternative Switches =-\n");
   AST_RWLIST_TRAVERSE(&switches, sw, list)
      ast_cli(a->fd, "%s: %s\n", sw->name, sw->description);

   AST_RWLIST_UNLOCK(&switches);

   return CLI_SUCCESS;
}

static char *handle_show_applications(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   struct ast_app *aa;
   int like = 0, describing = 0;
   int total_match = 0;    /* Number of matches in like clause */
   int total_apps = 0;  /* Number of apps registered */
   static char* choices[] = { "like", "describing", NULL };

   switch (cmd) {
   case CLI_INIT:
      e->command = "core show applications [like|describing]";
      e->usage = 
         "Usage: core show applications [{like|describing} <text>]\n"
         "       List applications which are currently available.\n"
         "       If 'like', <text> will be a substring of the app name\n"
         "       If 'describing', <text> will be a substring of the description\n";
      return NULL;
   case CLI_GENERATE:
      return (a->pos != 3) ? NULL : ast_cli_complete(a->word, choices, a->n);
   }

   AST_RWLIST_RDLOCK(&apps);

   if (AST_RWLIST_EMPTY(&apps)) {
      ast_cli(a->fd, "There are no registered applications\n");
      AST_RWLIST_UNLOCK(&apps);
      return CLI_SUCCESS;
   }

   /* core list applications like <keyword> */
   if ((a->argc == 5) && (!strcmp(a->argv[3], "like"))) {
      like = 1;
   } else if ((a->argc > 4) && (!strcmp(a->argv[3], "describing"))) {
      describing = 1;
   }

   /* core list applications describing <keyword1> [<keyword2>] [...] */
   if ((!like) && (!describing)) {
      ast_cli(a->fd, "    -= Registered Asterisk Applications =-\n");
   } else {
      ast_cli(a->fd, "    -= Matching Asterisk Applications =-\n");
   }

   AST_RWLIST_TRAVERSE(&apps, aa, list) {
      int printapp = 0;
      total_apps++;
      if (like) {
         if (strcasestr(aa->name, a->argv[4])) {
            printapp = 1;
            total_match++;
         }
      } else if (describing) {
         if (aa->description) {
            /* Match all words on command line */
            int i;
            printapp = 1;
            for (i = 4; i < a->argc; i++) {
               if (!strcasestr(aa->description, a->argv[i])) {
                  printapp = 0;
               } else {
                  total_match++;
               }
            }
         }
      } else {
         printapp = 1;
      }

      if (printapp) {
         ast_cli(a->fd,"  %20s: %s\n", aa->name, aa->synopsis ? aa->synopsis : "<Synopsis not available>");
      }
   }
   if ((!like) && (!describing)) {
      ast_cli(a->fd, "    -= %d Applications Registered =-\n",total_apps);
   } else {
      ast_cli(a->fd, "    -= %d Applications Matching =-\n",total_match);
   }

   AST_RWLIST_UNLOCK(&apps);

   return CLI_SUCCESS;
}

/*
 * 'show dialplan' CLI command implementation functions ...
 */
static char *complete_show_dialplan_context(const char *line, const char *word, int pos,
   int state)
{
   struct ast_context *c = NULL;
   char *ret = NULL;
   int which = 0;
   int wordlen;

   /* we are do completion of [exten@]context on second position only */
   if (pos != 2)
      return NULL;

   ast_rdlock_contexts();

   wordlen = strlen(word);

   /* walk through all contexts and return the n-th match */
   while ( (c = ast_walk_contexts(c)) ) {
      if (!strncasecmp(word, ast_get_context_name(c), wordlen) && ++which > state) {
         ret = ast_strdup(ast_get_context_name(c));
         break;
      }
   }

   ast_unlock_contexts();

   return ret;
}

/*! \brief Counters for the show dialplan manager command */
struct dialplan_counters {
   int total_items;
   int total_context;
   int total_exten;
   int total_prio;
   int context_existence;
   int extension_existence;
};

/*! \brief helper function to print an extension */
static void print_ext(struct ast_exten *e, char * buf, int buflen)
{
   int prio = ast_get_extension_priority(e);
   if (prio == PRIORITY_HINT) {
      snprintf(buf, buflen, "hint: %s",
         ast_get_extension_app(e));
   } else {
      snprintf(buf, buflen, "%d. %s(%s)",
         prio, ast_get_extension_app(e),
         (!ast_strlen_zero(ast_get_extension_app_data(e)) ? (char *)ast_get_extension_app_data(e) : ""));
   }
}

/* XXX not verified */
static int show_dialplan_helper(int fd, const char *context, const char *exten, struct dialplan_counters *dpc, struct ast_include *rinclude, int includecount, const char *includes[])
{
   struct ast_context *c = NULL;
   int res = 0, old_total_exten = dpc->total_exten;

   ast_rdlock_contexts();

   /* walk all contexts ... */
   while ( (c = ast_walk_contexts(c)) ) {
      struct ast_exten *e;
      struct ast_include *i;
      struct ast_ignorepat *ip;
      char buf[256], buf2[256];
      int context_info_printed = 0;

      if (context && strcmp(ast_get_context_name(c), context))
         continue;   /* skip this one, name doesn't match */

      dpc->context_existence = 1;

      ast_rdlock_context(c);

      /* are we looking for exten too? if yes, we print context
       * only if we find our extension.
       * Otherwise print context even if empty ?
       * XXX i am not sure how the rinclude is handled.
       * I think it ought to go inside.
       */
      if (!exten) {
         dpc->total_context++;
         ast_cli(fd, "[ Context '%s' created by '%s' ]\n",
            ast_get_context_name(c), ast_get_context_registrar(c));
         context_info_printed = 1;
      }

      /* walk extensions ... */
      e = NULL;
      while ( (e = ast_walk_context_extensions(c, e)) ) {
         struct ast_exten *p;

         if (exten && !ast_extension_match(ast_get_extension_name(e), exten))
            continue;   /* skip, extension match failed */

         dpc->extension_existence = 1;

         /* may we print context info? */
         if (!context_info_printed) {
            dpc->total_context++;
            if (rinclude) { /* TODO Print more info about rinclude */
               ast_cli(fd, "[ Included context '%s' created by '%s' ]\n",
                  ast_get_context_name(c), ast_get_context_registrar(c));
            } else {
               ast_cli(fd, "[ Context '%s' created by '%s' ]\n",
                  ast_get_context_name(c), ast_get_context_registrar(c));
            }
            context_info_printed = 1;
         }
         dpc->total_prio++;

         /* write extension name and first peer */
         if (e->matchcid)
            snprintf(buf, sizeof(buf), "'%s' (CID match '%s') => ", ast_get_extension_name(e), e->cidmatch);
         else
            snprintf(buf, sizeof(buf), "'%s' =>", ast_get_extension_name(e));

         print_ext(e, buf2, sizeof(buf2));

         ast_cli(fd, "  %-17s %-45s [%s]\n", buf, buf2,
            ast_get_extension_registrar(e));

         dpc->total_exten++;
         /* walk next extension peers */
         p = e;   /* skip the first one, we already got it */
         while ( (p = ast_walk_extension_priorities(e, p)) ) {
            const char *el = ast_get_extension_label(p);
            dpc->total_prio++;
            if (el)
               snprintf(buf, sizeof(buf), "   [%s]", el);
            else
               buf[0] = '\0';
            print_ext(p, buf2, sizeof(buf2));

            ast_cli(fd,"  %-17s %-45s [%s]\n", buf, buf2,
               ast_get_extension_registrar(p));
         }
      }

      /* walk included and write info ... */
      i = NULL;
      while ( (i = ast_walk_context_includes(c, i)) ) {
         snprintf(buf, sizeof(buf), "'%s'", ast_get_include_name(i));
         if (exten) {
            /* Check all includes for the requested extension */
            if (includecount >= AST_PBX_MAX_STACK) {
               ast_log(LOG_WARNING, "Maximum include depth exceeded!\n");
            } else {
               int dupe = 0;
               int x;
               for (x = 0; x < includecount; x++) {
                  if (!strcasecmp(includes[x], ast_get_include_name(i))) {
                     dupe++;
                     break;
                  }
               }
               if (!dupe) {
                  includes[includecount] = ast_get_include_name(i);
                  show_dialplan_helper(fd, ast_get_include_name(i), exten, dpc, i, includecount + 1, includes);
               } else {
                  ast_log(LOG_WARNING, "Avoiding circular include of %s within %s\n", ast_get_include_name(i), context);
               }
            }
         } else {
            ast_cli(fd, "  Include =>        %-45s [%s]\n",
               buf, ast_get_include_registrar(i));
         }
      }

      /* walk ignore patterns and write info ... */
      ip = NULL;
      while ( (ip = ast_walk_context_ignorepats(c, ip)) ) {
         const char *ipname = ast_get_ignorepat_name(ip);
         char ignorepat[AST_MAX_EXTENSION];
         snprintf(buf, sizeof(buf), "'%s'", ipname);
         snprintf(ignorepat, sizeof(ignorepat), "_%s.", ipname);
         if (!exten || ast_extension_match(ignorepat, exten)) {
            ast_cli(fd, "  Ignore pattern => %-45s [%s]\n",
               buf, ast_get_ignorepat_registrar(ip));
         }
      }
      if (!rinclude) {
         struct ast_sw *sw = NULL;
         while ( (sw = ast_walk_context_switches(c, sw)) ) {
            snprintf(buf, sizeof(buf), "'%s/%s'",
               ast_get_switch_name(sw),
               ast_get_switch_data(sw));
            ast_cli(fd, "  Alt. Switch =>    %-45s [%s]\n",
               buf, ast_get_switch_registrar(sw));
         }
      }
      
      ast_unlock_context(c);

      /* if we print something in context, make an empty line */
      if (context_info_printed)
         ast_cli(fd, "\n");
   }
   ast_unlock_contexts();

   return (dpc->total_exten == old_total_exten) ? -1 : res;
}

static int show_debug_helper(int fd, const char *context, const char *exten, struct dialplan_counters *dpc, struct ast_include *rinclude, int includecount, const char *includes[])
{
   struct ast_context *c = NULL;
   int res = 0, old_total_exten = dpc->total_exten;

   ast_cli(fd,"\n     In-mem exten Trie for Fast Extension Pattern Matching:\n\n");

   ast_cli(fd,"\n           Explanation: Node Contents Format = <char(s) to match>:<pattern?>:<specif>:[matched extension]\n");
   ast_cli(fd,    "                        Where <char(s) to match> is a set of chars, any one of which should match the current character\n");
   ast_cli(fd,    "                              <pattern?>: Y if this a pattern match (eg. _XZN[5-7]), N otherwise\n");
   ast_cli(fd,    "                              <specif>: an assigned 'exactness' number for this matching char. The lower the number, the more exact the match\n");
   ast_cli(fd,    "                              [matched exten]: If all chars matched to this point, which extension this matches. In form: EXTEN:<exten string>\n");
   ast_cli(fd,    "                        In general, you match a trie node to a string character, from left to right. All possible matching chars\n");
   ast_cli(fd,    "                        are in a string vertically, separated by an unbroken string of '+' characters.\n\n");
   ast_rdlock_contexts();

   /* walk all contexts ... */
   while ( (c = ast_walk_contexts(c)) ) {
      int context_info_printed = 0;

      if (context && strcmp(ast_get_context_name(c), context))
         continue;   /* skip this one, name doesn't match */

      dpc->context_existence = 1;

      if (!c->pattern_tree)
         ast_exists_extension(NULL, c->name, "s", 1, ""); /* do this to force the trie to built, if it is not already */

      ast_rdlock_context(c);

      dpc->total_context++;
      ast_cli(fd, "[ Context '%s' created by '%s' ]\n",
         ast_get_context_name(c), ast_get_context_registrar(c));
      context_info_printed = 1;
      
      if (c->pattern_tree)
      {
         cli_match_char_tree(c->pattern_tree, " ", fd);
      } else {
         ast_cli(fd,"\n     No Pattern Trie present. Perhaps the context is empty...or there is trouble...\n\n");
      }

      ast_unlock_context(c);

      /* if we print something in context, make an empty line */
      if (context_info_printed)
         ast_cli(fd, "\n");
   }
   ast_unlock_contexts();

   return (dpc->total_exten == old_total_exten) ? -1 : res;
}

static char *handle_show_dialplan(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   char *exten = NULL, *context = NULL;
   /* Variables used for different counters */
   struct dialplan_counters counters;
   const char *incstack[AST_PBX_MAX_STACK];

   switch (cmd) {
   case CLI_INIT:
      e->command = "dialplan show";
      e->usage = 
         "Usage: dialplan show [[exten@]context]\n"
         "       Show dialplan\n";
      return NULL;
   case CLI_GENERATE:   
      return complete_show_dialplan_context(a->line, a->word, a->pos, a->n);
   }

   memset(&counters, 0, sizeof(counters));

   if (a->argc != 2 && a->argc != 3)
      return CLI_SHOWUSAGE;

   /* we obtain [exten@]context? if yes, split them ... */
   if (a->argc == 3) {
      if (strchr(a->argv[2], '@')) {   /* split into exten & context */
         context = ast_strdupa(a->argv[2]);
         exten = strsep(&context, "@");
         /* change empty strings to NULL */
         if (ast_strlen_zero(exten))
            exten = NULL;
      } else { /* no '@' char, only context given */
         context = a->argv[2];
      }
      if (ast_strlen_zero(context))
         context = NULL;
   }
   /* else Show complete dial plan, context and exten are NULL */
   show_dialplan_helper(a->fd, context, exten, &counters, NULL, 0, incstack);

   /* check for input failure and throw some error messages */
   if (context && !counters.context_existence) {
      ast_cli(a->fd, "There is no existence of '%s' context\n", context);
      return CLI_FAILURE;
   }

   if (exten && !counters.extension_existence) {
      if (context)
         ast_cli(a->fd, "There is no existence of %s@%s extension\n",
            exten, context);
      else
         ast_cli(a->fd,
            "There is no existence of '%s' extension in all contexts\n",
            exten);
      return CLI_FAILURE;
   }

   ast_cli(a->fd,"-= %d %s (%d %s) in %d %s. =-\n",
            counters.total_exten, counters.total_exten == 1 ? "extension" : "extensions",
            counters.total_prio, counters.total_prio == 1 ? "priority" : "priorities",
            counters.total_context, counters.total_context == 1 ? "context" : "contexts");

   /* everything ok */
   return CLI_SUCCESS;
}

/*! \brief Send ack once */
static char *handle_debug_dialplan(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   char *exten = NULL, *context = NULL;
   /* Variables used for different counters */
   struct dialplan_counters counters;
   const char *incstack[AST_PBX_MAX_STACK];

   switch (cmd) {
   case CLI_INIT:
      e->command = "dialplan debug";
      e->usage = 
         "Usage: dialplan debug [context]\n"
         "       Show dialplan context Trie(s). Usually only useful to folks debugging the deep internals of the fast pattern matcher\n";
      return NULL;
   case CLI_GENERATE:   
      return complete_show_dialplan_context(a->line, a->word, a->pos, a->n);
   }

   memset(&counters, 0, sizeof(counters));

   if (a->argc != 2 && a->argc != 3)
      return CLI_SHOWUSAGE;

   /* we obtain [exten@]context? if yes, split them ... */
   /* note: we ignore the exten totally here .... */
   if (a->argc == 3) {
      if (strchr(a->argv[2], '@')) {   /* split into exten & context */
         context = ast_strdupa(a->argv[2]);
         exten = strsep(&context, "@");
         /* change empty strings to NULL */
         if (ast_strlen_zero(exten))
            exten = NULL;
      } else { /* no '@' char, only context given */
         context = a->argv[2];
      }
      if (ast_strlen_zero(context))
         context = NULL;
   }
   /* else Show complete dial plan, context and exten are NULL */
   show_debug_helper(a->fd, context, exten, &counters, NULL, 0, incstack);

   /* check for input failure and throw some error messages */
   if (context && !counters.context_existence) {
      ast_cli(a->fd, "There is no existence of '%s' context\n", context);
      return CLI_FAILURE;
   }


   ast_cli(a->fd,"-= %d %s. =-\n",
         counters.total_context, counters.total_context == 1 ? "context" : "contexts");

   /* everything ok */
   return CLI_SUCCESS;
}

/*! \brief Send ack once */
static void manager_dpsendack(struct mansession *s, const struct message *m)
{
   astman_send_listack(s, m, "DialPlan list will follow", "start");
}

/*! \brief Show dialplan extensions
 * XXX this function is similar but not exactly the same as the CLI's
 * show dialplan. Must check whether the difference is intentional or not.
 */
static int manager_show_dialplan_helper(struct mansession *s, const struct message *m,
               const char *actionidtext, const char *context,
               const char *exten, struct dialplan_counters *dpc,
               struct ast_include *rinclude)
{
   struct ast_context *c;
   int res = 0, old_total_exten = dpc->total_exten;

   if (ast_strlen_zero(exten))
      exten = NULL;
   if (ast_strlen_zero(context))
      context = NULL;

   ast_debug(3, "manager_show_dialplan: Context: -%s- Extension: -%s-\n", context, exten);

   /* try to lock contexts */
   if (ast_rdlock_contexts()) {
      astman_send_error(s, m, "Failed to lock contexts");
      ast_log(LOG_WARNING, "Failed to lock contexts list for manager: listdialplan\n");
      return -1;
   }

   c = NULL;      /* walk all contexts ... */
   while ( (c = ast_walk_contexts(c)) ) {
      struct ast_exten *e;
      struct ast_include *i;
      struct ast_ignorepat *ip;

      if (context && strcmp(ast_get_context_name(c), context) != 0)
         continue;   /* not the name we want */

      dpc->context_existence = 1;

      ast_debug(3, "manager_show_dialplan: Found Context: %s \n", ast_get_context_name(c));

      if (ast_rdlock_context(c)) {  /* failed to lock */
         ast_debug(3, "manager_show_dialplan: Failed to lock context\n");
         continue;
      }

      /* XXX note- an empty context is not printed */
      e = NULL;      /* walk extensions in context  */
      while ( (e = ast_walk_context_extensions(c, e)) ) {
         struct ast_exten *p;

         /* looking for extension? is this our extension? */
         if (exten && !ast_extension_match(ast_get_extension_name(e), exten)) {
            /* not the one we are looking for, continue */
            ast_debug(3, "manager_show_dialplan: Skipping extension %s\n", ast_get_extension_name(e));
            continue;
         }
         ast_debug(3, "manager_show_dialplan: Found Extension: %s \n", ast_get_extension_name(e));

         dpc->extension_existence = 1;

         /* may we print context info? */ 
         dpc->total_context++;
         dpc->total_exten++;

         p = NULL;      /* walk next extension peers */
         while ( (p = ast_walk_extension_priorities(e, p)) ) {
            int prio = ast_get_extension_priority(p);

            dpc->total_prio++;
            if (!dpc->total_items++)
               manager_dpsendack(s, m);
            astman_append(s, "Event: ListDialplan\r\n%s", actionidtext);
            astman_append(s, "Context: %s\r\nExtension: %s\r\n", ast_get_context_name(c), ast_get_extension_name(e) );

            /* XXX maybe make this conditional, if p != e ? */
            if (ast_get_extension_label(p))
               astman_append(s, "ExtensionLabel: %s\r\n", ast_get_extension_label(p));

            if (prio == PRIORITY_HINT) {
               astman_append(s, "Priority: hint\r\nApplication: %s\r\n", ast_get_extension_app(p));
            } else {
               astman_append(s, "Priority: %d\r\nApplication: %s\r\nAppData: %s\r\n", prio, ast_get_extension_app(p), (char *) ast_get_extension_app_data(p));
            }
            astman_append(s, "Registrar: %s\r\n\r\n", ast_get_extension_registrar(e));
         }
      }

      i = NULL;      /* walk included and write info ... */
      while ( (i = ast_walk_context_includes(c, i)) ) {
         if (exten) {
            /* Check all includes for the requested extension */
            manager_show_dialplan_helper(s, m, actionidtext, ast_get_include_name(i), exten, dpc, i);
         } else {
            if (!dpc->total_items++)
               manager_dpsendack(s, m);
            astman_append(s, "Event: ListDialplan\r\n%s", actionidtext);
            astman_append(s, "Context: %s\r\nIncludeContext: %s\r\nRegistrar: %s\r\n", ast_get_context_name(c), ast_get_include_name(i), ast_get_include_registrar(i));
            astman_append(s, "\r\n");
            ast_debug(3, "manager_show_dialplan: Found Included context: %s \n", ast_get_include_name(i));
         }
      }

      ip = NULL;  /* walk ignore patterns and write info ... */
      while ( (ip = ast_walk_context_ignorepats(c, ip)) ) {
         const char *ipname = ast_get_ignorepat_name(ip);
         char ignorepat[AST_MAX_EXTENSION];

         snprintf(ignorepat, sizeof(ignorepat), "_%s.", ipname);
         if (!exten || ast_extension_match(ignorepat, exten)) {
            if (!dpc->total_items++)
               manager_dpsendack(s, m);
            astman_append(s, "Event: ListDialplan\r\n%s", actionidtext);
            astman_append(s, "Context: %s\r\nIgnorePattern: %s\r\nRegistrar: %s\r\n", ast_get_context_name(c), ipname, ast_get_ignorepat_registrar(ip));
            astman_append(s, "\r\n");
         }
      }
      if (!rinclude) {
         struct ast_sw *sw = NULL;
         while ( (sw = ast_walk_context_switches(c, sw)) ) {
            if (!dpc->total_items++)
               manager_dpsendack(s, m);
            astman_append(s, "Event: ListDialplan\r\n%s", actionidtext);
            astman_append(s, "Context: %s\r\nSwitch: %s/%s\r\nRegistrar: %s\r\n", ast_get_context_name(c), ast_get_switch_name(sw), ast_get_switch_data(sw), ast_get_switch_registrar(sw));  
            astman_append(s, "\r\n");
            ast_debug(3, "manager_show_dialplan: Found Switch : %s \n", ast_get_switch_name(sw));
         }
      }

      ast_unlock_context(c);
   }
   ast_unlock_contexts();

   if (dpc->total_exten == old_total_exten) {
      ast_debug(3, "manager_show_dialplan: Found nothing new\n");
      /* Nothing new under the sun */
      return -1;
   } else {
      return res;
   }
}

/*! \brief  Manager listing of dial plan */
static int manager_show_dialplan(struct mansession *s, const struct message *m)
{
   const char *exten, *context;
   const char *id = astman_get_header(m, "ActionID");
   char idtext[256];
   int res;

   /* Variables used for different counters */
   struct dialplan_counters counters;

   if (!ast_strlen_zero(id))
      snprintf(idtext, sizeof(idtext), "ActionID: %s\r\n", id);
   else
      idtext[0] = '\0';

   memset(&counters, 0, sizeof(counters));

   exten = astman_get_header(m, "Extension");
   context = astman_get_header(m, "Context");
   
   res = manager_show_dialplan_helper(s, m, idtext, context, exten, &counters, NULL);

   if (context && !counters.context_existence) {
      char errorbuf[BUFSIZ];
   
      snprintf(errorbuf, sizeof(errorbuf), "Did not find context %s", context);
      astman_send_error(s, m, errorbuf);
      return 0;
   }
   if (exten && !counters.extension_existence) {
      char errorbuf[BUFSIZ];

      if (context)
         snprintf(errorbuf, sizeof(errorbuf), "Did not find extension %s@%s", exten, context);
      else
         snprintf(errorbuf, sizeof(errorbuf), "Did not find extension %s in any context", exten);
      astman_send_error(s, m, errorbuf);
      return 0;
   }

   manager_event(EVENT_FLAG_CONFIG, "ShowDialPlanComplete",
      "EventList: Complete\r\n"
      "ListItems: %d\r\n"
      "ListExtensions: %d\r\n"
      "ListPriorities: %d\r\n"   
      "ListContexts: %d\r\n"  
      "%s"
      "\r\n", counters.total_items, counters.total_exten, counters.total_prio, counters.total_context, idtext);

   /* everything ok */
   return 0;
}

static char mandescr_show_dialplan[] =
"Description: Show dialplan contexts and extensions.\n"
"Be aware that showing the full dialplan may take a lot of capacity\n"
"Variables: \n"
" ActionID: <id>     Action ID for this AMI transaction (optional)\n"
" Extension: <extension>   Extension (Optional)\n"
" Context: <context>    Context (Optional)\n"
"\n";

/*! \brief CLI support for listing global variables in a parseable way */
static char *handle_show_globals(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   int i = 0;
   struct ast_var_t *newvariable;

   switch (cmd) {
   case CLI_INIT:
      e->command = "dialplan show globals";
      e->usage = 
         "Usage: dialplan show globals\n"
         "       List current global dialplan variables and their values\n";
      return NULL;
   case CLI_GENERATE:
      return NULL;
   }

   ast_rwlock_rdlock(&globalslock);
   AST_LIST_TRAVERSE (&globals, newvariable, entries) {
      i++;
      ast_cli(a->fd, "   %s=%s\n", ast_var_name(newvariable), ast_var_value(newvariable));
   }
   ast_rwlock_unlock(&globalslock);
   ast_cli(a->fd, "\n    -- %d variable(s)\n", i);

   return CLI_SUCCESS;
}

static char *handle_show_globals_deprecated(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{

   char *res = handle_show_globals(e, cmd, a);
   if (cmd == CLI_INIT)
      e->command = "core show globals";
   return res;
}

#ifdef AST_DEVMODE
static char *handle_show_device2extenstate(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   struct ast_devstate_aggregate agg;
   int i, j, exten, combined;

   switch (cmd) {
   case CLI_INIT:
      e->command = "core show device2extenstate";
      e->usage =
         "Usage: core show device2extenstate\n"
         "       Lists device state to extension state combinations.\n";
   case CLI_GENERATE:
      return NULL;
   }
   for (i = 0; i < AST_DEVICE_TOTAL; i++) {
      for (j = 0; j < AST_DEVICE_TOTAL; j++) {
         ast_devstate_aggregate_init(&agg);
         ast_devstate_aggregate_add(&agg, i);
         ast_devstate_aggregate_add(&agg, j);
         combined = ast_devstate_aggregate_result(&agg);
         exten = ast_devstate_to_extenstate(combined);
         ast_cli(a->fd, "\n Exten:%14s  CombinedDevice:%12s  Dev1:%12s  Dev2:%12s", ast_extension_state2str(exten), ast_devstate_str(combined), ast_devstate_str(j), ast_devstate_str(i));
      }
   }
   ast_cli(a->fd, "\n");
   return CLI_SUCCESS;
}
#endif

/*! \brief CLI support for listing chanvar's variables in a parseable way */
static char *handle_show_chanvar(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   struct ast_channel *chan = NULL;
   struct ast_str *vars = ast_str_alloca(BUFSIZ * 4); /* XXX large because we might have lots of channel vars */

   switch (cmd) {
   case CLI_INIT:
      e->command = "dialplan show chanvar";
      e->usage = 
         "Usage: dialplan show chanvar <channel>\n"
         "       List current channel variables and their values\n";
      return NULL;
   case CLI_GENERATE:
      return ast_complete_channels(a->line, a->word, a->pos, a->n, 3);
   }

   if (a->argc != e->args + 1)
      return CLI_SHOWUSAGE;

   if (!(chan = ast_get_channel_by_name_locked(a->argv[e->args]))) {
      ast_cli(a->fd, "Channel '%s' not found\n", a->argv[e->args]);
      return CLI_FAILURE;
   }

   pbx_builtin_serialize_variables(chan, &vars);
   if (vars->str) {
      ast_cli(a->fd, "\nVariables for channel %s:\n%s\n", a->argv[e->args], vars->str);
   }
   ast_channel_unlock(chan);
   return CLI_SUCCESS;
}

static char *handle_set_global(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   switch (cmd) {
   case CLI_INIT:
      e->command = "dialplan set global";
      e->usage = 
         "Usage: dialplan set global <name> <value>\n"
         "       Set global dialplan variable <name> to <value>\n";
      return NULL;
   case CLI_GENERATE:
      return NULL;   
   }

   if (a->argc != e->args + 2)
      return CLI_SHOWUSAGE;

   pbx_builtin_setvar_helper(NULL, a->argv[3], a->argv[4]);
   ast_cli(a->fd, "\n    -- Global variable '%s' set to '%s'\n", a->argv[3], a->argv[4]);

   return CLI_SUCCESS;
}

static char *handle_set_global_deprecated(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   char *res = handle_set_global(e, cmd, a);
   if (cmd == CLI_INIT)
      e->command = "core set global";
   return res;
}

static char *handle_set_chanvar(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   struct ast_channel *chan;
   const char *chan_name, *var_name, *var_value;

   switch (cmd) {
   case CLI_INIT:
      e->command = "dialplan set chanvar";
      e->usage = 
         "Usage: dialplan set chanvar <channel> <varname> <value>\n"
         "       Set channel variable <varname> to <value>\n";
      return NULL;
   case CLI_GENERATE:
      return ast_complete_channels(a->line, a->word, a->pos, a->n, 3);
   }

   if (a->argc != e->args + 3)
      return CLI_SHOWUSAGE;

   chan_name = a->argv[e->args];
   var_name = a->argv[e->args + 1];
   var_value = a->argv[e->args + 2];

   if (!(chan = ast_get_channel_by_name_locked(chan_name))) {
      ast_cli(a->fd, "Channel '%s' not found\n", chan_name);
      return CLI_FAILURE;
   }

   pbx_builtin_setvar_helper(chan, var_name, var_value);
   ast_channel_unlock(chan);
   ast_cli(a->fd, "\n    -- Channel variable '%s' set to '%s' for '%s'\n",  var_name, var_value, chan_name);

   return CLI_SUCCESS;
}

static char *handle_set_chanvar_deprecated(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   char *res = handle_set_chanvar(e, cmd, a);
   if (cmd == CLI_INIT)
      e->command = "core set chanvar";
   return res;
}

static char *handle_set_extenpatternmatchnew(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   int oldval = 0;
   
   switch (cmd) {
   case CLI_INIT:
      e->command = "dialplan set extenpatternmatchnew true";
      e->usage = 
         "Usage: dialplan set extenpatternmatchnew true|false\n"
         "       Use the NEW extension pattern matching algorithm, true or false.\n";
      return NULL;
   case CLI_GENERATE:
      return NULL;   
   }

   if (a->argc != 4)
      return CLI_SHOWUSAGE;

   oldval =  pbx_set_extenpatternmatchnew(1);
   
   if (oldval)
      ast_cli(a->fd, "\n    -- Still using the NEW pattern match algorithm for extension names in the dialplan.\n");
   else
      ast_cli(a->fd, "\n    -- Switched to using the NEW pattern match algorithm for extension names in the dialplan.\n");

   return CLI_SUCCESS;
}

static char *handle_unset_extenpatternmatchnew(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
   int oldval = 0;
   
   switch (cmd) {
   case CLI_INIT:
      e->command = "dialplan set extenpatternmatchnew false";
      e->usage = 
         "Usage: dialplan set extenpatternmatchnew true|false\n"
         "       Use the NEW extension pattern matching algorithm, true or false.\n";
      return NULL;
   case CLI_GENERATE:
      return NULL;   
   }

   if (a->argc != 4)
      return CLI_SHOWUSAGE;

   oldval =  pbx_set_extenpatternmatchnew(0);
   
   if (!oldval)
      ast_cli(a->fd, "\n    -- Still using the OLD pattern match algorithm for extension names in the dialplan.\n");
   else
      ast_cli(a->fd, "\n    -- Switched to using the OLD pattern match algorithm for extension names in the dialplan.\n");

   return CLI_SUCCESS;
}

/*
 * Deprecated CLI commands
 */

static struct ast_cli_entry cli_show_globals_deprecated = AST_CLI_DEFINE(handle_show_globals_deprecated, "Show global dialplan variables.");
static struct ast_cli_entry cli_set_chanvar_deprecated = AST_CLI_DEFINE(handle_set_chanvar_deprecated, "Set a channel variable.");
static struct ast_cli_entry cli_set_global_deprecated = AST_CLI_DEFINE(handle_set_global_deprecated, "Set global dialplan variable.");

/*
 * CLI entries for upper commands ...
 */
static struct ast_cli_entry pbx_cli[] = {
   AST_CLI_DEFINE(handle_show_applications, "Shows registered dialplan applications"),
   AST_CLI_DEFINE(handle_show_functions, "Shows registered dialplan functions"),
   AST_CLI_DEFINE(handle_show_switches, "Show alternative switches"),
   AST_CLI_DEFINE(handle_show_hints, "Show dialplan hints"),
   AST_CLI_DEFINE(handle_show_hint, "Show dialplan hint"),
   AST_CLI_DEFINE(handle_show_globals, "Show global dialplan variables", .deprecate_cmd = &cli_show_globals_deprecated),
#ifdef AST_DEVMODE
   AST_CLI_DEFINE(handle_show_device2extenstate, "Show expected exten state from multiple device states"),
#endif
   AST_CLI_DEFINE(handle_show_chanvar, "Show channel variables"),
   AST_CLI_DEFINE(handle_show_function, "Describe a specific dialplan function"),
   AST_CLI_DEFINE(handle_show_application, "Describe a specific dialplan application"),
   AST_CLI_DEFINE(handle_set_global, "Set global dialplan variable", .deprecate_cmd = &cli_set_global_deprecated),
   AST_CLI_DEFINE(handle_set_chanvar, "Set a channel variable", .deprecate_cmd = &cli_set_chanvar_deprecated),
   AST_CLI_DEFINE(handle_show_dialplan, "Show dialplan"),
   AST_CLI_DEFINE(handle_debug_dialplan, "Show fast extension pattern matching data structures"),
   AST_CLI_DEFINE(handle_unset_extenpatternmatchnew, "Use the Old extension pattern matching algorithm."),
   AST_CLI_DEFINE(handle_set_extenpatternmatchnew, "Use the New extension pattern matching algorithm."),
};

static void unreference_cached_app(struct ast_app *app)
{
   struct ast_context *context = NULL;
   struct ast_exten *eroot = NULL, *e = NULL;

   ast_rdlock_contexts();
   while ((context = ast_walk_contexts(context))) {
      while ((eroot = ast_walk_context_extensions(context, eroot))) {
         while ((e = ast_walk_extension_priorities(eroot, e))) {
            if (e->cached_app == app)
               e->cached_app = NULL;
         }
      }
   }
   ast_unlock_contexts();

   return;
}

int ast_unregister_application(const char *app)
{
   struct ast_app *tmp;

   AST_RWLIST_WRLOCK(&apps);
   AST_RWLIST_TRAVERSE_SAFE_BEGIN(&apps, tmp, list) {
      if (!strcasecmp(app, tmp->name)) {
         unreference_cached_app(tmp);
         AST_RWLIST_REMOVE_CURRENT(list);
         ast_verb(2, "Unregistered application '%s'\n", tmp->name);
         ast_free(tmp);
         break;
      }
   }
   AST_RWLIST_TRAVERSE_SAFE_END;
   AST_RWLIST_UNLOCK(&apps);

   return tmp ? 0 : -1;
}

struct ast_context *ast_context_find_or_create(struct ast_context **extcontexts, struct ast_hashtab *exttable, const char *name, const char *registrar)
{
   struct ast_context *tmp, **local_contexts;
   struct fake_context search;
   int length = sizeof(struct ast_context) + strlen(name) + 1;

   if (!contexts_table) {
      contexts_table = ast_hashtab_create(17,
                                 ast_hashtab_compare_contexts, 
                                 ast_hashtab_resize_java,
                                 ast_hashtab_newsize_java,
                                 ast_hashtab_hash_contexts,
                                 0);
   }
   
   ast_copy_string(search.name, name, sizeof(search.name));
   if (!extcontexts) {
      ast_rdlock_contexts();
      local_contexts = &contexts;
      tmp = ast_hashtab_lookup(contexts_table, &search);
      ast_unlock_contexts();
      if (tmp) {
         tmp->refcount++;
         return tmp;
      }
   } else { /* local contexts just in a linked list; search there for the new context; slow, linear search, but not frequent */
      local_contexts = extcontexts;
      tmp = ast_hashtab_lookup(exttable, &search);
      if (tmp) {
         tmp->refcount++;
         return tmp;
      }
   }
   
   if ((tmp = ast_calloc(1, length))) {
      ast_rwlock_init(&tmp->lock);
      ast_mutex_init(&tmp->macrolock);
      strcpy(tmp->name, name);
      tmp->root = NULL;
      tmp->root_table = NULL;
      tmp->registrar = ast_strdup(registrar);
      tmp->includes = NULL;
      tmp->ignorepats = NULL;
      tmp->refcount = 1;
   } else {
      ast_log(LOG_ERROR, "Danger! We failed to allocate a context for %s!\n", name);
      return NULL;
   }
   
   if (!extcontexts) {
      ast_wrlock_contexts();
      tmp->next = *local_contexts;
      *local_contexts = tmp;
      ast_hashtab_insert_safe(contexts_table, tmp); /*put this context into the tree */
      ast_unlock_contexts();
      ast_debug(1, "Registered context '%s'(%p) in table %p registrar: %s\n", tmp->name, tmp, contexts_table, registrar);
      ast_verb(3, "Registered extension context '%s' (%p) in table %p; registrar: %s\n", tmp->name, tmp, contexts_table, registrar);
   } else {
      tmp->next = *local_contexts;
      if (exttable)
         ast_hashtab_insert_immediate(exttable, tmp); /*put this context into the tree */
      
      *local_contexts = tmp;
      ast_debug(1, "Registered context '%s'(%p) in local table %p; registrar: %s\n", tmp->name, tmp, exttable, registrar);
      ast_verb(3, "Registered extension context '%s' (%p) in local table %p; registrar: %s\n", tmp->name, tmp, exttable, registrar);
   }
   return tmp;
}

void __ast_context_destroy(struct ast_context *list, struct ast_hashtab *contexttab, struct ast_context *con, const char *registrar);

struct store_hint {
   char *context;
   char *exten;
   AST_LIST_HEAD_NOLOCK(, ast_state_cb) callbacks;
   int laststate;
   AST_LIST_ENTRY(store_hint) list;
   char data[1];
};

AST_LIST_HEAD(store_hints, store_hint);

static void context_merge_incls_swits_igps_other_registrars(struct ast_context *new, struct ast_context *old, const char *registrar)
{
   struct ast_include *i;
   struct ast_ignorepat *ip;
   struct ast_sw *sw;
   
   ast_verb(3, "merging incls/swits/igpats from old(%s) to new(%s) context, registrar = %s\n", ast_get_context_name(old), ast_get_context_name(new), registrar);
   /* copy in the includes, switches, and ignorepats */
   /* walk through includes */
   for (i = NULL; (i = ast_walk_context_includes(old, i)) ; ) {
      if (strcmp(ast_get_include_registrar(i), registrar) == 0)
         continue; /* not mine */
      ast_context_add_include2(new, ast_get_include_name(i), ast_get_include_registrar(i));
   }
   
   /* walk through switches */
   for (sw = NULL; (sw = ast_walk_context_switches(old, sw)) ; ) {
      if (strcmp(ast_get_switch_registrar(sw), registrar) == 0)
         continue; /* not mine */
      ast_context_add_switch2(new, ast_get_switch_name(sw), ast_get_switch_data(sw), ast_get_switch_eval(sw), ast_get_switch_registrar(sw));
   }
   
   /* walk thru ignorepats ... */
   for (ip = NULL; (ip = ast_walk_context_ignorepats(old, ip)); ) {
      if (strcmp(ast_get_ignorepat_registrar(ip), registrar) == 0)
         continue; /* not mine */
      ast_context_add_ignorepat2(new, ast_get_ignorepat_name(ip), ast_get_ignorepat_registrar(ip));
   }
}


/* the purpose of this routine is to duplicate a context, with all its substructure,
   except for any extens that have a matching registrar */
static void context_merge(struct ast_context **extcontexts, struct ast_hashtab *exttable, struct ast_context *context, const char *registrar)
{
   struct ast_context *new = ast_hashtab_lookup(exttable, context); /* is there a match in the new set? */
   struct ast_exten *exten_item, *prio_item, *new_exten_item, *new_prio_item;
   struct ast_hashtab_iter *exten_iter;
   struct ast_hashtab_iter *prio_iter;
   int insert_count = 0;
   int first = 1;
   
   /* We'll traverse all the extensions/prios, and see which are not registrar'd with
      the current registrar, and copy them to the new context. If the new context does not
      exist, we'll create it "on demand". If no items are in this context to copy, then we'll
      only create the empty matching context if the old one meets the criteria */
   
   if (context->root_table) {
      exten_iter = ast_hashtab_start_traversal(context->root_table);
      while ((exten_item=ast_hashtab_next(exten_iter))) {
         if (new) {
            new_exten_item = ast_hashtab_lookup(new->root_table, exten_item);
         } else {
            new_exten_item = NULL;
         }
         prio_iter = ast_hashtab_start_traversal(exten_item->peer_table);
         while ((prio_item=ast_hashtab_next(prio_iter))) {
            int res1;
            char *dupdstr;
            
            if (new_exten_item) {
               new_prio_item = ast_hashtab_lookup(new_exten_item->peer_table, prio_item);
            } else {
               new_prio_item = NULL;
            }
            if (strcmp(prio_item->registrar,registrar) == 0) {
               continue;
            }
            /* make sure the new context exists, so we have somewhere to stick this exten/prio */
            if (!new) {
               new = ast_context_find_or_create(extcontexts, exttable, context->name, prio_item->registrar); /* a new context created via priority from a different context in the old dialplan, gets its registrar from the prio's registrar */
            }

            /* copy in the includes, switches, and ignorepats */
            if (first) { /* but, only need to do this once */
               context_merge_incls_swits_igps_other_registrars(new, context, registrar);
               first = 0;
            }
            
            if (!new) {
               ast_log(LOG_ERROR,"Could not allocate a new context for %s in merge_and_delete! Danger!\n", context->name);
               return; /* no sense continuing. */
            }
            /* we will not replace existing entries in the new context with stuff from the old context.
               but, if this is because of some sort of registrar conflict, we ought to say something... */
            
            dupdstr = ast_strdup(prio_item->data);
            
            res1 = ast_add_extension2(new, 0, prio_item->exten, prio_item->priority, prio_item->label, 
                                prio_item->cidmatch, prio_item->app, dupdstr, prio_item->datad, prio_item->registrar);
            if (!res1 && new_exten_item && new_prio_item){
               ast_verb(3,"Dropping old dialplan item %s/%s/%d [%s(%s)] (registrar=%s) due to conflict with new dialplan\n",
                     context->name, prio_item->exten, prio_item->priority, prio_item->app, (char*)prio_item->data, prio_item->registrar);
            } else {
               /* we do NOT pass the priority data from the old to the new -- we pass a copy of it, so no changes to the current dialplan take place,
                and no double frees take place, either! */
               insert_count++;
            }
         }
         ast_hashtab_end_traversal(prio_iter);
      }
      ast_hashtab_end_traversal(exten_iter);
   }
   
   if (!insert_count && !new && (strcmp(context->registrar, registrar) != 0 ||
        (strcmp(context->registrar, registrar) == 0 && context->refcount > 1))) {
      /* we could have given it the registrar of the other module who incremented the refcount,
         but that's not available, so we give it the registrar we know about */
      new = ast_context_find_or_create(extcontexts, exttable, context->name, context->registrar);
      
      /* copy in the includes, switches, and ignorepats */
      context_merge_incls_swits_igps_other_registrars(new, context, registrar);
   }
}


/* XXX this does not check that multiple contexts are merged */
void ast_merge_contexts_and_delete(struct ast_context **extcontexts, struct ast_hashtab *exttable, const char *registrar)
{
   double ft;
   struct ast_context *tmp, *oldcontextslist;
   struct ast_hashtab *oldtable;
   struct store_hints store = AST_LIST_HEAD_INIT_VALUE;
   struct store_hint *this;
   struct ast_hint *hint;
   struct ast_exten *exten;
   int length;
   struct ast_state_cb *thiscb;
   struct ast_hashtab_iter *iter;
   
   /* it is very important that this function hold the hint list lock _and_ the conlock
      during its operation; not only do we need to ensure that the list of contexts
      and extensions does not change, but also that no hint callbacks (watchers) are
      added or removed during the merge/delete process

      in addition, the locks _must_ be taken in this order, because there are already
      other code paths that use this order
   */
   
   struct timeval begintime, writelocktime, endlocktime, enddeltime;
   int wrlock_ver;
   
   begintime = ast_tvnow();
   ast_rdlock_contexts();
   iter = ast_hashtab_start_traversal(contexts_table);
   while ((tmp = ast_hashtab_next(iter))) {
      context_merge(extcontexts, exttable, tmp, registrar);
   }
   ast_hashtab_end_traversal(iter);
   wrlock_ver = ast_wrlock_contexts_version();
   
   ast_unlock_contexts(); /* this feels real retarded, but you must do
                       what you must do If this isn't done, the following 
                        wrlock is a guraranteed deadlock */
   ast_wrlock_contexts();
   if (ast_wrlock_contexts_version() > wrlock_ver+1) {
      ast_log(LOG_WARNING,"==================!!!!!!!!!!!!!!!Something changed the contexts in the middle of merging contexts!\n");
   }
   
   AST_RWLIST_WRLOCK(&hints);
   writelocktime = ast_tvnow();

   /* preserve all watchers for hints associated with this registrar */
   AST_RWLIST_TRAVERSE(&hints, hint, list) {
      if (!AST_LIST_EMPTY(&hint->callbacks) && !strcmp(registrar, hint->exten->parent->registrar)) {
         length = strlen(hint->exten->exten) + strlen(hint->exten->parent->name) + 2 + sizeof(*this);
         if (!(this = ast_calloc(1, length)))
            continue;
         AST_LIST_APPEND_LIST(&this->callbacks, &hint->callbacks, entry);
         this->laststate = hint->laststate;
         this->context = this->data;
         strcpy(this->data, hint->exten->parent->name);
         this->exten = this->data + strlen(this->context) + 1;
         strcpy(this->exten, hint->exten->exten);
         AST_LIST_INSERT_HEAD(&store, this, list);
      }
   }

   /* save the old table and list */
   oldtable = contexts_table;
   oldcontextslist = contexts;

   /* move in the new table and list */
   contexts_table = exttable;
   contexts = *extcontexts;
   
   /* restore the watchers for hints that can be found; notify those that
      cannot be restored
   */
   while ((this = AST_LIST_REMOVE_HEAD(&store, list))) {
      struct pbx_find_info q = { .stacklen = 0 };
      exten = pbx_find_extension(NULL, NULL, &q, this->context, this->exten, PRIORITY_HINT, NULL, "", E_MATCH);
      /* If this is a pattern, dynamically create a new extension for this
       * particular match.  Note that this will only happen once for each
       * individual extension, because the pattern will no longer match first.
       */
      if (exten && exten->exten[0] == '_') {
         ast_add_extension_nolock(exten->parent->name, 0, this->exten, PRIORITY_HINT, NULL,
            0, exten->app, ast_strdup(exten->data), ast_free_ptr, registrar);
         /* rwlocks are not recursive locks */
         exten = ast_hint_extension_nolock(NULL, this->context, this->exten);
      }

      /* Find the hint in the list of hints */
      AST_RWLIST_TRAVERSE(&hints, hint, list) {
         if (hint->exten == exten)
            break;
      }
      if (!exten || !hint) {
         /* this hint has been removed, notify the watchers */
         while ((thiscb = AST_LIST_REMOVE_HEAD(&this->callbacks, entry))) {
            thiscb->callback(this->context, this->exten, AST_EXTENSION_REMOVED, thiscb->data);
            ast_free(thiscb);
         }
      } else {
         AST_LIST_APPEND_LIST(&hint->callbacks, &this->callbacks, entry);
         hint->laststate = this->laststate;
      }
      ast_free(this);
   }

   AST_RWLIST_UNLOCK(&hints);
   ast_unlock_contexts();
   endlocktime = ast_tvnow();
   
   /* the old list and hashtab no longer are relevant, delete them while the rest of asterisk
      is now freely using the new stuff instead */
   
   ast_hashtab_destroy(oldtable, NULL);
   
   for (tmp = oldcontextslist; tmp; ) {
      struct ast_context *next;  /* next starting point */
      next = tmp->next;
      __ast_internal_context_destroy(tmp);
      tmp = next;
   }
   enddeltime = ast_tvnow();
   
   ft = ast_tvdiff_us(writelocktime, begintime);
   ft /= 1000000.0;
   ast_verb(3,"Time to scan old dialplan and merge leftovers back into the new: %8.6f sec\n", ft);
   
   ft = ast_tvdiff_us(endlocktime, writelocktime);
   ft /= 1000000.0;
   ast_verb(3,"Time to restore hints and swap in new dialplan: %8.6f sec\n", ft);

   ft = ast_tvdiff_us(enddeltime, endlocktime);
   ft /= 1000000.0;
   ast_verb(3,"Time to delete the old dialplan: %8.6f sec\n", ft);

   ft = ast_tvdiff_us(enddeltime, begintime);
   ft /= 1000000.0;
   ast_verb(3,"Total time merge_contexts_delete: %8.6f sec\n", ft);
   return;
}

/*
 * errno values
 *  EBUSY  - can't lock
 *  ENOENT - no existence of context
 */
int ast_context_add_include(const char *context, const char *include, const char *registrar)
{
   int ret = -1;
   struct ast_context *c = find_context_locked(context);

   if (c) {
      ret = ast_context_add_include2(c, include, registrar);
      ast_unlock_contexts();
   }
   return ret;
}

/*! \brief Helper for get_range.
 * return the index of the matching entry, starting from 1.
 * If names is not supplied, try numeric values.
 */
static int lookup_name(const char *s, char *const names[], int max)
{
   int i;

   if (names) {
      for (i = 0; names[i]; i++) {
         if (!strcasecmp(s, names[i]))
            return i+1;
      }
   } else if (sscanf(s, "%2d", &i) == 1 && i >= 1 && i <= max) {
      return i;
   }
   return 0; /* error return */
}

/*! \brief helper function to return a range up to max (7, 12, 31 respectively).
 * names, if supplied, is an array of names that should be mapped to numbers.
 */
static unsigned get_range(char *src, int max, char *const names[], const char *msg)
{
   int s, e; /* start and ending position */
   unsigned int mask = 0;

   /* Check for whole range */
   if (ast_strlen_zero(src) || !strcmp(src, "*")) {
      s = 0;
      e = max - 1;
   } else {
      /* Get start and ending position */
      char *c = strchr(src, '-');
      if (c)
         *c++ = '\0';
      /* Find the start */
      s = lookup_name(src, names, max);
      if (!s) {
         ast_log(LOG_WARNING, "Invalid %s '%s', assuming none\n", msg, src);
         return 0;
      }
      s--;
      if (c) { /* find end of range */
         e = lookup_name(c, names, max);
         if (!e) {
            ast_log(LOG_WARNING, "Invalid end %s '%s', assuming none\n", msg, c);
            return 0;
         }
         e--;
      } else
         e = s;
   }
   /* Fill the mask. Remember that ranges are cyclic */
   mask = 1 << e; /* initialize with last element */
   while (s != e) {
      if (s >= max) {
         s = 0;
         mask |= (1 << s);
      } else {
         mask |= (1 << s);
         s++;
      }
   }
   return mask;
}

/*! \brief store a bitmask of valid times, one bit each 2 minute */
static void get_timerange(struct ast_timing *i, char *times)
{
   char *e;
   int x;
   int s1, s2;
   int e1, e2;
   /* int cth, ctm; */

   /* start disabling all times, fill the fields with 0's, as they may contain garbage */
   memset(i->minmask, 0, sizeof(i->minmask));

   /* 2-minutes per bit, since the mask has only 32 bits :( */
   /* Star is all times */
   if (ast_strlen_zero(times) || !strcmp(times, "*")) {
      for (x = 0; x < 24; x++)
         i->minmask[x] = 0x3fffffff; /* 30 bits */
      return;
   }
   /* Otherwise expect a range */
   e = strchr(times, '-');
   if (!e) {
      ast_log(LOG_WARNING, "Time range is not valid. Assuming no restrictions based on time.\n");
      return;
   }
   *e++ = '\0';
   /* XXX why skip non digits ? */
   while (*e && !isdigit(*e))
      e++;
   if (!*e) {
      ast_log(LOG_WARNING, "Invalid time range.  Assuming no restrictions based on time.\n");
      return;
   }
   if (sscanf(times, "%2d:%2d", &s1, &s2) != 2) {
      ast_log(LOG_WARNING, "%s isn't a time.  Assuming no restrictions based on time.\n", times);
      return;
   }
   if (sscanf(e, "%2d:%2d", &e1, &e2) != 2) {
      ast_log(LOG_WARNING, "%s isn't a time.  Assuming no restrictions based on time.\n", e);
      return;
   }
   /* XXX this needs to be optimized */
#if 1
   s1 = s1 * 30 + s2/2;
   if ((s1 < 0) || (s1 >= 24*30)) {
      ast_log(LOG_WARNING, "%s isn't a valid start time. Assuming no time.\n", times);
      return;
   }
   e1 = e1 * 30 + e2/2;
   if ((e1 < 0) || (e1 >= 24*30)) {
      ast_log(LOG_WARNING, "%s isn't a valid end time. Assuming no time.\n", e);
      return;
   }
   /* Go through the time and enable each appropriate bit */
   for (x=s1;x != e1;x = (x + 1) % (24 * 30)) {
      i->minmask[x/30] |= (1 << (x % 30));
   }
   /* Do the last one */
   i->minmask[x/30] |= (1 << (x % 30));
#else
   for (cth = 0; cth < 24; cth++) {
      /* Initialize masks to blank */
      i->minmask[cth] = 0;
      for (ctm = 0; ctm < 30; ctm++) {
         if (
         /* First hour with more than one hour */
               (((cth == s1) && (ctm >= s2)) &&
                ((cth < e1)))
         /* Only one hour */
         ||    (((cth == s1) && (ctm >= s2)) &&
                ((cth == e1) && (ctm <= e2)))
         /* In between first and last hours (more than 2 hours) */
         ||    ((cth > s1) &&
                (cth < e1))
         /* Last hour with more than one hour */
         ||    ((cth > s1) &&
                ((cth == e1) && (ctm <= e2)))
         )
            i->minmask[cth] |= (1 << (ctm / 2));
      }
   }
#endif
   /* All done */
   return;
}

static char *days[] =
{
   "sun",
   "mon",
   "tue",
   "wed",
   "thu",
   "fri",
   "sat",
   NULL,
};

static char *months[] =
{
   "jan",
   "feb",
   "mar",
   "apr",
   "may",
   "jun",
   "jul",
   "aug",
   "sep",
   "oct",
   "nov",
   "dec",
   NULL,
};

int ast_build_timing(struct ast_timing *i, const char *info_in)
{
   char info_save[256];
   char *info;

   /* Check for empty just in case */
   if (ast_strlen_zero(info_in))
      return 0;
   /* make a copy just in case we were passed a static string */
   ast_copy_string(info_save, info_in, sizeof(info_save));
   info = info_save;
   /* Assume everything except time */
   i->monthmask = 0xfff;   /* 12 bits */
   i->daymask = 0x7fffffffU; /* 31 bits */
   i->dowmask = 0x7f; /* 7 bits */
   /* on each call, use strsep() to move info to the next argument */
   get_timerange(i, strsep(&info, "|,"));
   if (info)
      i->dowmask = get_range(strsep(&info, "|,"), 7, days, "day of week");
   if (info)
      i->daymask = get_range(strsep(&info, "|,"), 31, NULL, "day");
   if (info)
      i->monthmask = get_range(strsep(&info, "|,"), 12, months, "month");
   return 1;
}

int ast_check_timing(const struct ast_timing *i)
{
   struct ast_tm tm;
   struct timeval now = ast_tvnow();

   ast_localtime(&now, &tm, NULL);

   /* If it's not the right month, return */
   if (!(i->monthmask & (1 << tm.tm_mon)))
      return 0;

   /* If it's not that time of the month.... */
   /* Warning, tm_mday has range 1..31! */
   if (!(i->daymask & (1 << (tm.tm_mday-1))))
      return 0;

   /* If it's not the right day of the week */
   if (!(i->dowmask & (1 << tm.tm_wday)))
      return 0;

   /* Sanity check the hour just to be safe */
   if ((tm.tm_hour < 0) || (tm.tm_hour > 23)) {
      ast_log(LOG_WARNING, "Insane time...\n");
      return 0;
   }

   /* Now the tough part, we calculate if it fits
      in the right time based on min/hour */
   if (!(i->minmask[tm.tm_hour] & (1 << (tm.tm_min / 2))))
      return 0;

   /* If we got this far, then we're good */
   return 1;
}

/*
 * errno values
 *  ENOMEM - out of memory
 *  EBUSY  - can't lock
 *  EEXIST - already included
 *  EINVAL - there is no existence of context for inclusion
 */
int ast_context_add_include2(struct ast_context *con, const char *value,
   const char *registrar)
{
   struct ast_include *new_include;
   char *c;
   struct ast_include *i, *il = NULL; /* include, include_last */
   int length;
   char *p;

   length = sizeof(struct ast_include);
   length += 2 * (strlen(value) + 1);

   /* allocate new include structure ... */
   if (!(new_include = ast_calloc(1, length)))
      return -1;
   /* Fill in this structure. Use 'p' for assignments, as the fields
    * in the structure are 'const char *'
    */
   p = new_include->stuff;
   new_include->name = p;
   strcpy(p, value);
   p += strlen(value) + 1;
   new_include->rname = p;
   strcpy(p, value);
   /* Strip off timing info, and process if it is there */
   if ( (c = strchr(p, ',')) ) {
      *c++ = '\0';
           new_include->hastime = ast_build_timing(&(new_include->timing), c);
   }
   new_include->next      = NULL;
   new_include->registrar = registrar;

   ast_wrlock_context(con);

   /* ... go to last include and check if context is already included too... */
   for (i = con->includes; i; i = i->next) {
      if (!strcasecmp(i->name, new_include->name)) {
         ast_free(new_include);
         ast_unlock_context(con);
         errno = EEXIST;
         return -1;
      }
      il = i;
   }

   /* ... include new context into context list, unlock, return */
   if (il)
      il->next = new_include;
   else
      con->includes = new_include;
   ast_verb(3, "Including context '%s' in context '%s'\n", new_include->name, ast_get_context_name(con));

   ast_unlock_context(con);

   return 0;
}

/*
 * errno values
 *  EBUSY  - can't lock
 *  ENOENT - no existence of context
 */
int ast_context_add_switch(const char *context, const char *sw, const char *data, int eval, const char *registrar)
{
   int ret = -1;
   struct ast_context *c = find_context_locked(context);

   if (c) { /* found, add switch to this context */
      ret = ast_context_add_switch2(c, sw, data, eval, registrar);
      ast_unlock_contexts();
   }
   return ret;
}

/*
 * errno values
 *  ENOMEM - out of memory
 *  EBUSY  - can't lock
 *  EEXIST - already included
 *  EINVAL - there is no existence of context for inclusion
 */
int ast_context_add_switch2(struct ast_context *con, const char *value,
   const char *data, int eval, const char *registrar)
{
   struct ast_sw *new_sw;
   struct ast_sw *i;
   int length;
   char *p;

   length = sizeof(struct ast_sw);
   length += strlen(value) + 1;
   if (data)
      length += strlen(data);
   length++;

   /* allocate new sw structure ... */
   if (!(new_sw = ast_calloc(1, length)))
      return -1;
   /* ... fill in this structure ... */
   p = new_sw->stuff;
   new_sw->name = p;
   strcpy(new_sw->name, value);
   p += strlen(value) + 1;
   new_sw->data = p;
   if (data) {
      strcpy(new_sw->data, data);
      p += strlen(data) + 1;
   } else {
      strcpy(new_sw->data, "");
      p++;
   }
   new_sw->eval     = eval;
   new_sw->registrar = registrar;

   /* ... try to lock this context ... */
   ast_wrlock_context(con);

   /* ... go to last sw and check if context is already swd too... */
   AST_LIST_TRAVERSE(&con->alts, i, list) {
      if (!strcasecmp(i->name, new_sw->name) && !strcasecmp(i->data, new_sw->data)) {
         ast_free(new_sw);
         ast_unlock_context(con);
         errno = EEXIST;
         return -1;
      }
   }

   /* ... sw new context into context list, unlock, return */
   AST_LIST_INSERT_TAIL(&con->alts, new_sw, list);

   ast_verb(3, "Including switch '%s/%s' in context '%s'\n", new_sw->name, new_sw->data, ast_get_context_name(con));

   ast_unlock_context(con);

   return 0;
}

/*
 * EBUSY  - can't lock
 * ENOENT - there is not context existence
 */
int ast_context_remove_ignorepat(const char *context, const char *ignorepat, const char *registrar)
{
   int ret = -1;
   struct ast_context *c = find_context_locked(context);

   if (c) {
      ret = ast_context_remove_ignorepat2(c, ignorepat, registrar);
      ast_unlock_contexts();
   }
   return ret;
}

int ast_context_remove_ignorepat2(struct ast_context *con, const char *ignorepat, const char *registrar)
{
   struct ast_ignorepat *ip, *ipl = NULL;

   ast_wrlock_context(con);

   for (ip = con->ignorepats; ip; ip = ip->next) {
      if (!strcmp(ip->pattern, ignorepat) &&
         (!registrar || (registrar == ip->registrar))) {
         if (ipl) {
            ipl->next = ip->next;
            ast_free(ip);
         } else {
            con->ignorepats = ip->next;
            ast_free(ip);
         }
         ast_unlock_context(con);
         return 0;
      }
      ipl = ip;
   }

   ast_unlock_context(con);
   errno = EINVAL;
   return -1;
}

/*
 * EBUSY - can't lock
 * ENOENT - there is no existence of context
 */
int ast_context_add_ignorepat(const char *context, const char *value, const char *registrar)
{
   int ret = -1;
   struct ast_context *c = find_context_locked(context);

   if (c) {
      ret = ast_context_add_ignorepat2(c, value, registrar);
      ast_unlock_contexts();
   }
   return ret;
}

int ast_context_add_ignorepat2(struct ast_context *con, const char *value, const char *registrar)
{
   struct ast_ignorepat *ignorepat, *ignorepatc, *ignorepatl = NULL;
   int length;
   char *pattern;
   length = sizeof(struct ast_ignorepat);
   length += strlen(value) + 1;
   if (!(ignorepat = ast_calloc(1, length)))
      return -1;
   /* The cast to char * is because we need to write the initial value.
    * The field is not supposed to be modified otherwise.  Also, gcc 4.2
    * sees the cast as dereferencing a type-punned pointer and warns about
    * it.  This is the workaround (we're telling gcc, yes, that's really
    * what we wanted to do).
    */
   pattern = (char *) ignorepat->pattern;
   strcpy(pattern, value);
   ignorepat->next = NULL;
   ignorepat->registrar = registrar;
   ast_wrlock_context(con);
   for (ignorepatc = con->ignorepats; ignorepatc; ignorepatc = ignorepatc->next) {
      ignorepatl = ignorepatc;
      if (!strcasecmp(ignorepatc->pattern, value)) {
         /* Already there */
         ast_unlock_context(con);
         errno = EEXIST;
         return -1;
      }
   }
   if (ignorepatl)
      ignorepatl->next = ignorepat;
   else
      con->ignorepats = ignorepat;
   ast_unlock_context(con);
   return 0;

}

int ast_ignore_pattern(const char *context, const char *pattern)
{
   struct ast_context *con = ast_context_find(context);
   if (con) {
      struct ast_ignorepat *pat;
      for (pat = con->ignorepats; pat; pat = pat->next) {
         if (ast_extension_match(pat->pattern, pattern))
            return 1;
      }
   }

   return 0;
}

/*
 * ast_add_extension_nolock -- use only in situations where the conlock is already held
 * ENOENT  - no existence of context
 *
 */
static int ast_add_extension_nolock(const char *context, int replace, const char *extension,
   int priority, const char *label, const char *callerid,
   const char *application, void *data, void (*datad)(void *), const char *registrar)
{
   int ret = -1;
   struct ast_context *c = find_context(context);

   if (c) {
      ret = ast_add_extension2_lockopt(c, replace, extension, priority, label, callerid,
         application, data, datad, registrar, 0, 0);
   }
   
   return ret;
}
/*
 * EBUSY   - can't lock
 * ENOENT  - no existence of context
 *
 */
int ast_add_extension(const char *context, int replace, const char *extension,
   int priority, const char *label, const char *callerid,
   const char *application, void *data, void (*datad)(void *), const char *registrar)
{
   int ret = -1;
   struct ast_context *c = find_context_locked(context);

   if (c) {
      ret = ast_add_extension2(c, replace, extension, priority, label, callerid,
         application, data, datad, registrar);
      ast_unlock_contexts();
   }
   
   return ret;
}

int ast_explicit_goto(struct ast_channel *chan, const char *context, const char *exten, int priority)
{
   if (!chan)
      return -1;

   ast_channel_lock(chan);

   if (!ast_strlen_zero(context))
      ast_copy_string(chan->context, context, sizeof(chan->context));
   if (!ast_strlen_zero(exten))
      ast_copy_string(chan->exten, exten, sizeof(chan->exten));
   if (priority > -1) {
      chan->priority = priority;
      /* see flag description in channel.h for explanation */
      if (ast_test_flag(chan, AST_FLAG_IN_AUTOLOOP))
         chan->priority--;
   }

   ast_channel_unlock(chan);

   return 0;
}

int ast_async_goto(struct ast_channel *chan, const char *context, const char *exten, int priority)
{
   int res = 0;

   ast_channel_lock(chan);

   if (chan->pbx) { /* This channel is currently in the PBX */
      ast_explicit_goto(chan, context, exten, priority + 1);
      ast_softhangup_nolock(chan, AST_SOFTHANGUP_ASYNCGOTO);
   } else {
      /* In order to do it when the channel doesn't really exist within
         the PBX, we have to make a new channel, masquerade, and start the PBX
         at the new location */
      struct ast_channel *tmpchan = ast_channel_alloc(0, chan->_state, 0, 0, chan->accountcode, chan->exten, chan->context, chan->amaflags, "AsyncGoto/%s", chan->name);
      if (!tmpchan) {
         res = -1;
      } else {
         if (chan->cdr) {
            ast_cdr_discard(tmpchan->cdr);
            tmpchan->cdr = ast_cdr_dup(chan->cdr);  /* share the love */
         }
         /* Make formats okay */
         tmpchan->readformat = chan->readformat;
         tmpchan->writeformat = chan->writeformat;
         /* Setup proper location */
         ast_explicit_goto(tmpchan,
            S_OR(context, chan->context), S_OR(exten, chan->exten), priority);

         /* Masquerade into temp channel */
         if (ast_channel_masquerade(tmpchan, chan)) {
            /* Failed to set up the masquerade.  It's probably chan_local
             * in the middle of optimizing itself out.  Sad. :( */
            ast_hangup(tmpchan);
            tmpchan = NULL;
            res = -1;
         } else {
            /* Grab the locks and get going */
            ast_channel_lock(tmpchan);
            ast_do_masquerade(tmpchan);
            ast_channel_unlock(tmpchan);
            /* Start the PBX going on our stolen channel */
            if (ast_pbx_start(tmpchan)) {
               ast_log(LOG_WARNING, "Unable to start PBX on %s\n", tmpchan->name);
               ast_hangup(tmpchan);
               res = -1;
            }
         }
      }
   }
   ast_channel_unlock(chan);
   return res;
}

int ast_async_goto_by_name(const char *channame, const char *context, const char *exten, int priority)
{
   struct ast_channel *chan;
   int res = -1;

   chan = ast_get_channel_by_name_locked(channame);
   if (chan) {
      res = ast_async_goto(chan, context, exten, priority);
      ast_channel_unlock(chan);
   }
   return res;
}

/*! \brief copy a string skipping whitespace */
static int ext_strncpy(char *dst, const char *src, int len)
{
   int count = 0;

   while (*src && (count < len - 1)) {
      switch (*src) {
      case ' ':
         /* otherwise exten => [a-b],1,... doesn't work */
         /*    case '-': */
         /* Ignore */
         break;
      default:
         *dst = *src;
         dst++;
      }
      src++;
      count++;
   }
   *dst = '\0';

   return count;
}

/*! 
 * \brief add the extension in the priority chain.
 * \retval 0 on success.
 * \retval -1 on failure.
*/
static int add_pri(struct ast_context *con, struct ast_exten *tmp,
   struct ast_exten *el, struct ast_exten *e, int replace)
{
   return add_pri_lockopt(con, tmp, el, e, replace, 1);
}

/*! 
 * \brief add the extension in the priority chain.
 * \retval 0 on success.
 * \retval -1 on failure.
*/
static int add_pri_lockopt(struct ast_context *con, struct ast_exten *tmp,
   struct ast_exten *el, struct ast_exten *e, int replace, int lockhints)
{
   struct ast_exten *ep;
   struct ast_exten *eh=e;

   for (ep = NULL; e ; ep = e, e = e->peer) {
      if (e->priority >= tmp->priority)
         break;
   }
   if (!e) {   /* go at the end, and ep is surely set because the list is not empty */
      ast_hashtab_insert_safe(eh->peer_table, tmp);
      
      if (tmp->label) {
         ast_hashtab_insert_safe(eh->peer_label_table, tmp);
      }
      ep->peer = tmp;
      return 0;   /* success */
   }
   if (e->priority == tmp->priority) {
      /* Can't have something exactly the same.  Is this a
         replacement?  If so, replace, otherwise, bonk. */
      if (!replace) {
         ast_log(LOG_WARNING, "Unable to register extension '%s', priority %d in '%s', already in use\n", tmp->exten, tmp->priority, con->name);
         if (tmp->datad) {
            tmp->datad(tmp->data);
            /* if you free this, null it out */
            tmp->data = NULL;
         }
         
         ast_free(tmp);
         return -1;
      }
      /* we are replacing e, so copy the link fields and then update
       * whoever pointed to e to point to us
       */
      tmp->next = e->next; /* not meaningful if we are not first in the peer list */
      tmp->peer = e->peer; /* always meaningful */
      if (ep)  {     /* We're in the peer list, just insert ourselves */
         ast_hashtab_remove_object_via_lookup(eh->peer_table,e);

         if (e->label) {
            ast_hashtab_remove_object_via_lookup(eh->peer_label_table,e);
         }
         
         ast_hashtab_insert_safe(eh->peer_table,tmp);
         if (tmp->label) {
            ast_hashtab_insert_safe(eh->peer_label_table,tmp);
         }
         
         ep->peer = tmp;
      } else if (el) {     /* We're the first extension. Take over e's functions */
         struct match_char *x = add_exten_to_pattern_tree(con, e, 1);
         tmp->peer_table = e->peer_table;
         tmp->peer_label_table = e->peer_label_table;
         ast_hashtab_remove_object_via_lookup(tmp->peer_table,e);
         ast_hashtab_insert_safe(tmp->peer_table,tmp);
         if (e->label) {
            ast_hashtab_remove_object_via_lookup(tmp->peer_label_table, e);
         }
         if (tmp->label) {
            ast_hashtab_insert_safe(tmp->peer_label_table, tmp);
         }
         
         ast_hashtab_remove_object_via_lookup(con->root_table, e);
         ast_hashtab_insert_safe(con->root_table, tmp);
         el->next = tmp;
         /* The pattern trie points to this exten; replace the pointer,
            and all will be well */
         if (x) { /* if the trie isn't formed yet, don't sweat this */
            if (x->exten) { /* this test for safety purposes */
               x->exten = tmp; /* replace what would become a bad pointer */
            } else {
               ast_log(LOG_ERROR,"Trying to delete an exten from a context, but the pattern tree node returned isn't an extension\n");
            }
         }
      } else {       /* We're the very first extension.  */
         struct match_char *x = add_exten_to_pattern_tree(con, e, 1);
         ast_hashtab_remove_object_via_lookup(con->root_table, e);
         ast_hashtab_insert_safe(con->root_table, tmp);
         tmp->peer_table = e->peer_table;
         tmp->peer_label_table = e->peer_label_table;
         ast_hashtab_remove_object_via_lookup(tmp->peer_table, e);
         ast_hashtab_insert_safe(tmp->peer_table, tmp);
         if (e->label) {
            ast_hashtab_remove_object_via_lookup(tmp->peer_label_table, e);
         }
         if (tmp->label) {
            ast_hashtab_insert_safe(tmp->peer_label_table, tmp);
         }
         
         ast_hashtab_remove_object_via_lookup(con->root_table, e);
         ast_hashtab_insert_safe(con->root_table, tmp);
         con->root = tmp;
         /* The pattern trie points to this exten; replace the pointer,
            and all will be well */
         if (x) { /* if the trie isn't formed yet; no problem */
            if (x->exten) { /* this test for safety purposes */
               x->exten = tmp; /* replace what would become a bad pointer */
            } else {
               ast_log(LOG_ERROR,"Trying to delete an exten from a context, but the pattern tree node returned isn't an extension\n");
            }
         }
      }
      if (tmp->priority == PRIORITY_HINT)
         ast_change_hint(e,tmp);
      /* Destroy the old one */
      if (e->datad)
         e->datad(e->data);
      ast_free(e);
   } else { /* Slip ourselves in just before e */
      tmp->peer = e;
      tmp->next = e->next; /* extension chain, or NULL if e is not the first extension */
      if (ep) {         /* Easy enough, we're just in the peer list */
         if (tmp->label) {
            ast_hashtab_insert_safe(eh->peer_label_table, tmp);
         }
         ast_hashtab_insert_safe(eh->peer_table, tmp);
         ep->peer = tmp;
      } else {       /* we are the first in some peer list, so link in the ext list */
         tmp->peer_table = e->peer_table;
         tmp->peer_label_table = e->peer_label_table;
         e->peer_table = 0;
         e->peer_label_table = 0;
         ast_hashtab_insert_safe(tmp->peer_table, tmp);
         if (tmp->label) {
            ast_hashtab_insert_safe(tmp->peer_label_table, tmp);
         }
         ast_hashtab_remove_object_via_lookup(con->root_table, e);
         ast_hashtab_insert_safe(con->root_table, tmp);
         if (el)
            el->next = tmp;   /* in the middle... */
         else
            con->root = tmp; /* ... or at the head */
         e->next = NULL;   /* e is no more at the head, so e->next must be reset */
      }
      /* And immediately return success. */
      if (tmp->priority == PRIORITY_HINT) {
         if (lockhints) {
            ast_add_hint(tmp);
         } else {
            ast_add_hint_nolock(tmp);
         }
      }
   }
   return 0;
}

/*! \brief
 * Main interface to add extensions to the list for out context.
 *
 * We sort extensions in order of matching preference, so that we can
 * stop the search as soon as we find a suitable match.
 * This ordering also takes care of wildcards such as '.' (meaning
 * "one or more of any character") and '!' (which is 'earlymatch',
 * meaning "zero or more of any character" but also impacts the
 * return value from CANMATCH and EARLYMATCH.
 *
 * The extension match rules defined in the devmeeting 2006.05.05 are
 * quite simple: WE SELECT THE LONGEST MATCH.
 * In detail, "longest" means the number of matched characters in
 * the extension. In case of ties (e.g. _XXX and 333) in the length
 * of a pattern, we give priority to entries with the smallest cardinality
 * (e.g, [5-9] comes before [2-8] before the former has only 5 elements,
 * while the latter has 7, etc.
 * In case of same cardinality, the first element in the range counts.
 * If we still have a tie, any final '!' will make this as a possibly
 * less specific pattern.
 *
 * EBUSY - can't lock
 * EEXIST - extension with the same priority exist and no replace is set
 *
 */
int ast_add_extension2(struct ast_context *con,
   int replace, const char *extension, int priority, const char *label, const char *callerid,
   const char *application, void *data, void (*datad)(void *),
   const char *registrar)
{
   return ast_add_extension2_lockopt(con, replace, extension, priority, label, callerid, application, data, datad, registrar, 1, 1);
}

/*! \brief
 * Does all the work of ast_add_extension2, but adds two args, to determine if 
 * context and hint locking should be done. In merge_and_delete, we need to do
 * this without locking, as the locks are already held.
 */
static int ast_add_extension2_lockopt(struct ast_context *con,
   int replace, const char *extension, int priority, const char *label, const char *callerid,
   const char *application, void *data, void (*datad)(void *),
   const char *registrar, int lockconts, int lockhints)
{
   /*
    * Sort extensions (or patterns) according to the rules indicated above.
    * These are implemented by the function ext_cmp()).
    * All priorities for the same ext/pattern/cid are kept in a list,
    * using the 'peer' field  as a link field..
    */
   struct ast_exten *tmp, *tmp2, *e, *el = NULL;
   int res;
   int length;
   char *p;
   char expand_buf[VAR_BUF_SIZE];
   struct ast_exten dummy_exten = {0};
   char dummy_name[1024];

   if (ast_strlen_zero(extension)) {
      ast_log(LOG_ERROR,"You have to be kidding-- add exten '' to context %s? Figure out a name and call me back. Action ignored.\n",
            con->name);
      return -1;
   }
   
   /* If we are adding a hint evalulate in variables and global variables */
   if (priority == PRIORITY_HINT && strstr(application, "${") && !strstr(extension, "_")) {
      struct ast_channel c = {0, };

      ast_copy_string(c.exten, extension, sizeof(c.exten));
      ast_copy_string(c.context, con->name, sizeof(c.context));
      pbx_substitute_variables_helper(&c, application, expand_buf, sizeof(expand_buf));
      application = expand_buf;
   }

   length = sizeof(struct ast_exten);
   length += strlen(extension) + 1;
   length += strlen(application) + 1;
   if (label)
      length += strlen(label) + 1;
   if (callerid)
      length += strlen(callerid) + 1;
   else
      length ++;  /* just the '\0' */

   /* Be optimistic:  Build the extension structure first */
   if (!(tmp = ast_calloc(1, length)))
      return -1;

   if (ast_strlen_zero(label)) /* let's turn empty labels to a null ptr */
      label = 0;

   /* use p as dst in assignments, as the fields are const char * */
   p = tmp->stuff;
   if (label) {
      tmp->label = p;
      strcpy(p, label);
      p += strlen(label) + 1;
   }
   tmp->exten = p;
   p += ext_strncpy(p, extension, strlen(extension) + 1) + 1;
   tmp->priority = priority;
   tmp->cidmatch = p;   /* but use p for assignments below */
   if (!ast_strlen_zero(callerid)) {
      p += ext_strncpy(p, callerid, strlen(callerid) + 1) + 1;
      tmp->matchcid = 1;
   } else {
      *p++ = '\0';
      tmp->matchcid = 0;
   }
   tmp->app = p;
   strcpy(p, application);
   tmp->parent = con;
   tmp->data = data;
   tmp->datad = datad;
   tmp->registrar = registrar;

   if (lockconts) {
      ast_wrlock_context(con);
   }
   
   if (con->pattern_tree) { /* usually, on initial load, the pattern_tree isn't formed until the first find_exten; so if we are adding
                        an extension, and the trie exists, then we need to incrementally add this pattern to it. */
      ast_copy_string(dummy_name, extension, sizeof(dummy_name));
      dummy_exten.exten = dummy_name;
      dummy_exten.matchcid = 0;
      dummy_exten.cidmatch = 0;
      tmp2 = ast_hashtab_lookup(con->root_table, &dummy_exten);
      if (!tmp2) {
         /* hmmm, not in the trie; */
         add_exten_to_pattern_tree(con, tmp, 0);
         ast_hashtab_insert_safe(con->root_table, tmp); /* for the sake of completeness */
      }
   }
   res = 0; /* some compilers will think it is uninitialized otherwise */
   for (e = con->root; e; el = e, e = e->next) {   /* scan the extension list */
      res = ext_cmp(e->exten, tmp->exten);
      if (res == 0) { /* extension match, now look at cidmatch */
         if (!e->matchcid && !tmp->matchcid)
            res = 0;
         else if (tmp->matchcid && !e->matchcid)
            res = 1;
         else if (e->matchcid && !tmp->matchcid)
            res = -1;
         else
            res = strcasecmp(e->cidmatch, tmp->cidmatch);
      }
      if (res >= 0)
         break;
   }
   if (e && res == 0) { /* exact match, insert in the pri chain */
      res = add_pri(con, tmp, el, e, replace);
      if (lockconts) {
         ast_unlock_context(con);
      }
      if (res < 0) {
         errno = EEXIST;   /* XXX do we care ? */
         return 0; /* XXX should we return -1 maybe ? */
      }
   } else {
      /*
       * not an exact match, this is the first entry with this pattern,
       * so insert in the main list right before 'e' (if any)
       */
      tmp->next = e;
      if (el) {  /* there is another exten already in this context */
         el->next = tmp;
         tmp->peer_table = ast_hashtab_create(13,
                     hashtab_compare_exten_numbers,
                     ast_hashtab_resize_java,
                     ast_hashtab_newsize_java,
                     hashtab_hash_priority,
                     0);
         tmp->peer_label_table = ast_hashtab_create(7,
                        hashtab_compare_exten_labels,
                        ast_hashtab_resize_java,
                        ast_hashtab_newsize_java,
                        hashtab_hash_labels,
                        0);
         if (label) {
            ast_hashtab_insert_safe(tmp->peer_label_table, tmp);
         }
         ast_hashtab_insert_safe(tmp->peer_table, tmp);
      } else {  /* this is the first exten in this context */
         if (!con->root_table)
            con->root_table = ast_hashtab_create(27,
                                       hashtab_compare_extens,
                                       ast_hashtab_resize_java,
                                       ast_hashtab_newsize_java,
                                       hashtab_hash_extens,
                                       0);
         con->root = tmp;
         con->root->peer_table = ast_hashtab_create(13,
                        hashtab_compare_exten_numbers,
                        ast_hashtab_resize_java,
                        ast_hashtab_newsize_java,
                        hashtab_hash_priority,
                        0);
         con->root->peer_label_table = ast_hashtab_create(7,
                           hashtab_compare_exten_labels,
                           ast_hashtab_resize_java,
                           ast_hashtab_newsize_java,
                           hashtab_hash_labels,
                           0);
         if (label) {
            ast_hashtab_insert_safe(con->root->peer_label_table, tmp);
         }
         ast_hashtab_insert_safe(con->root->peer_table, tmp);
            
      }
      ast_hashtab_insert_safe(con->root_table, tmp);
      if (lockconts) {
         ast_unlock_context(con);
      }
      if (tmp->priority == PRIORITY_HINT) {
         if (lockhints) {
            ast_add_hint(tmp);
         } else {
            ast_add_hint_nolock(tmp);
         }
      }
   }
   if (option_debug) {
      if (tmp->matchcid) {
         ast_debug(1, "Added extension '%s' priority %d (CID match '%s') to %s (%p)\n",
                 tmp->exten, tmp->priority, tmp->cidmatch, con->name, con);
      } else {
         ast_debug(1, "Added extension '%s' priority %d to %s (%p)\n",
                 tmp->exten, tmp->priority, con->name, con);
      }
   }

   if (tmp->matchcid) {
      ast_verb(3, "Added extension '%s' priority %d (CID match '%s') to %s (%p)\n",
             tmp->exten, tmp->priority, tmp->cidmatch, con->name, con);
   } else {
      ast_verb(3, "Added extension '%s' priority %d to %s (%p)\n",
             tmp->exten, tmp->priority, con->name, con);
   }
   
   return 0;
}

struct async_stat {
   pthread_t p;
   struct ast_channel *chan;
   char context[AST_MAX_CONTEXT];
   char exten[AST_MAX_EXTENSION];
   int priority;
   int timeout;
   char app[AST_MAX_EXTENSION];
   char appdata[1024];
};

static void *async_wait(void *data)
{
   struct async_stat *as = data;
   struct ast_channel *chan = as->chan;
   int timeout = as->timeout;
   int res;
   struct ast_frame *f;
   struct ast_app *app;

   while (timeout && (chan->_state != AST_STATE_UP)) {
      res = ast_waitfor(chan, timeout);
      if (res < 1)
         break;
      if (timeout > -1)
         timeout = res;
      f = ast_read(chan);
      if (!f)
         break;
      if (f->frametype == AST_FRAME_CONTROL) {
         if ((f->subclass == AST_CONTROL_BUSY)  ||
             (f->subclass == AST_CONTROL_CONGESTION) ) {
            ast_frfree(f);
            break;
         }
      }
      ast_frfree(f);
   }
   if (chan->_state == AST_STATE_UP) {
      if (!ast_strlen_zero(as->app)) {
         app = pbx_findapp(as->app);
         if (app) {
            ast_verb(3, "Launching %s(%s) on %s\n", as->app, as->appdata, chan->name);
            pbx_exec(chan, app, as->appdata);
         } else
            ast_log(LOG_WARNING, "No such application '%s'\n", as->app);
      } else {
         if (!ast_strlen_zero(as->context))
            ast_copy_string(chan->context, as->context, sizeof(chan->context));
         if (!ast_strlen_zero(as->exten))
            ast_copy_string(chan->exten, as->exten, sizeof(chan->exten));
         if (as->priority > 0)
            chan->priority = as->priority;
         /* Run the PBX */
         if (ast_pbx_run(chan)) {
            ast_log(LOG_ERROR, "Failed to start PBX on %s\n", chan->name);
         } else {
            /* PBX will have taken care of this */
            chan = NULL;
         }
      }
   }
   ast_free(as);
   if (chan)
      ast_hangup(chan);
   return NULL;
}

/*! 
 * \brief Function to post an empty cdr after a spool call fails.
 * \note This function posts an empty cdr for a failed spool call
*/
static int ast_pbx_outgoing_cdr_failed(void)
{
   /* allocate a channel */
   struct ast_channel *chan = ast_channel_alloc(0, AST_STATE_DOWN, 0, 0, "", "", "", 0, "%s", "");

   if (!chan)
      return -1;  /* failure */

   if (!chan->cdr) {
      /* allocation of the cdr failed */
      ast_channel_free(chan);   /* free the channel */
      return -1;                /* return failure */
   }

   /* allocation of the cdr was successful */
   ast_cdr_init(chan->cdr, chan);  /* initialize our channel's cdr */
   ast_cdr_start(chan->cdr);       /* record the start and stop time */
   ast_cdr_end(chan->cdr);
   ast_cdr_failed(chan->cdr);      /* set the status to failed */
   ast_cdr_detach(chan->cdr);      /* post and free the record */
   chan->cdr = NULL;
   ast_channel_free(chan);         /* free the channel */

   return 0;  /* success */
}

int ast_pbx_outgoing_exten(const char *type, int format, void *data, int timeout, const char *context, const char *exten, int priority, int *reason, int synchronous, const char *cid_num, const char *cid_name, struct ast_variable *vars, const char *account, struct ast_channel **channel)
{
   struct ast_channel *chan;
   struct async_stat *as;
   int res = -1, cdr_res = -1;
   struct outgoing_helper oh;

   if (synchronous) {
      oh.context = context;
      oh.exten = exten;
      oh.priority = priority;
      oh.cid_num = cid_num;
      oh.cid_name = cid_name;
      oh.account = account;
      oh.vars = vars;
      oh.parent_channel = NULL;

      chan = __ast_request_and_dial(type, format, data, timeout, reason, cid_num, cid_name, &oh);
      if (channel) {
         *channel = chan;
         if (chan)
            ast_channel_lock(chan);
      }
      if (chan) {
         if (chan->_state == AST_STATE_UP) {
               res = 0;
            ast_verb(4, "Channel %s was answered.\n", chan->name);

            if (synchronous > 1) {
               if (channel)
                  ast_channel_unlock(chan);
               if (ast_pbx_run(chan)) {
                  ast_log(LOG_ERROR, "Unable to run PBX on %s\n", chan->name);
                  if (channel)
                     *channel = NULL;
                  ast_hangup(chan);
                  chan = NULL;
                  res = -1;
               }
            } else {
               if (ast_pbx_start(chan)) {
                  ast_log(LOG_ERROR, "Unable to start PBX on %s\n", chan->name);
                  if (channel) {
                     *channel = NULL;
                     ast_channel_unlock(chan);
                  }
                  ast_hangup(chan);
                  res = -1;
               }
               chan = NULL;
            }
         } else {
            ast_verb(4, "Channel %s was never answered.\n", chan->name);

            if (chan->cdr) { /* update the cdr */
               /* here we update the status of the call, which sould be busy.
                * if that fails then we set the status to failed */
               if (ast_cdr_disposition(chan->cdr, chan->hangupcause))
                  ast_cdr_failed(chan->cdr);
            }

            if (channel) {
               *channel = NULL;
               ast_channel_unlock(chan);
            }
            ast_hangup(chan);
            chan = NULL;
         }
      }

      if (res < 0) { /* the call failed for some reason */
         if (*reason == 0) { /* if the call failed (not busy or no answer)
                        * update the cdr with the failed message */
            cdr_res = ast_pbx_outgoing_cdr_failed();
            if (cdr_res != 0) {
               res = cdr_res;
               goto outgoing_exten_cleanup;
            }
         }

         /* create a fake channel and execute the "failed" extension (if it exists) within the requested context */
         /* check if "failed" exists */
         if (ast_exists_extension(chan, context, "failed", 1, NULL)) {
            chan = ast_channel_alloc(0, AST_STATE_DOWN, 0, 0, "", "", "", 0, "OutgoingSpoolFailed");
            if (chan) {
               char failed_reason[4] = "";
               if (!ast_strlen_zero(context))
                  ast_copy_string(chan->context, context, sizeof(chan->context));
               set_ext_pri(chan, "failed", 1);
               ast_set_variables(chan, vars);
               snprintf(failed_reason, sizeof(failed_reason), "%d", *reason);
               pbx_builtin_setvar_helper(chan, "REASON", failed_reason);
               if (account)
                  ast_cdr_setaccount(chan, account);
               if (ast_pbx_run(chan)) {
                  ast_log(LOG_ERROR, "Unable to run PBX on %s\n", chan->name);
                  ast_hangup(chan);
               }
               chan = NULL;
            }
         }
      }
   } else {
      if (!(as = ast_calloc(1, sizeof(*as)))) {
         res = -1;
         goto outgoing_exten_cleanup;
      }
      chan = ast_request_and_dial(type, format, data, timeout, reason, cid_num, cid_name);
      if (channel) {
         *channel = chan;
         if (chan)
            ast_channel_lock(chan);
      }
      if (!chan) {
         ast_free(as);
         res = -1;
         goto outgoing_exten_cleanup;
      }
      as->chan = chan;
      ast_copy_string(as->context, context, sizeof(as->context));
      set_ext_pri(as->chan,  exten, priority);
      as->timeout = timeout;
      ast_set_variables(chan, vars);
      if (account)
         ast_cdr_setaccount(chan, account);
      if (ast_pthread_create_detached(&as->p, NULL, async_wait, as)) {
         ast_log(LOG_WARNING, "Failed to start async wait\n");
         ast_free(as);
         if (channel) {
            *channel = NULL;
            ast_channel_unlock(chan);
         }
         ast_hangup(chan);
         res = -1;
         goto outgoing_exten_cleanup;
      }
      res = 0;
   }
outgoing_exten_cleanup:
   ast_variables_destroy(vars);
   return res;
}

struct app_tmp {
   char app[256];
   char data[256];
   struct ast_channel *chan;
   pthread_t t;
};

/*! \brief run the application and free the descriptor once done */
static void *ast_pbx_run_app(void *data)
{
   struct app_tmp *tmp = data;
   struct ast_app *app;
   app = pbx_findapp(tmp->app);
   if (app) {
      ast_verb(4, "Launching %s(%s) on %s\n", tmp->app, tmp->data, tmp->chan->name);
      pbx_exec(tmp->chan, app, tmp->data);
   } else
      ast_log(LOG_WARNING, "No such application '%s'\n", tmp->app);
   ast_hangup(tmp->chan);
   ast_free(tmp);
   return NULL;
}

int ast_pbx_outgoing_app(const char *type, int format, void *data, int timeout, const char *app, const char *appdata, int *reason, int synchronous, const char *cid_num, const char *cid_name, struct ast_variable *vars, const char *account, struct ast_channel **locked_channel)
{
   struct ast_channel *chan;
   struct app_tmp *tmp;
   int res = -1, cdr_res = -1;
   struct outgoing_helper oh;

   memset(&oh, 0, sizeof(oh));
   oh.vars = vars;
   oh.account = account;

   if (locked_channel)
      *locked_channel = NULL;
   if (ast_strlen_zero(app)) {
      res = -1;
      goto outgoing_app_cleanup;
   }
   if (synchronous) {
      chan = __ast_request_and_dial(type, format, data, timeout, reason, cid_num, cid_name, &oh);
      if (chan) {
         ast_set_variables(chan, vars);
         if (account)
            ast_cdr_setaccount(chan, account);
         if (chan->_state == AST_STATE_UP) {
            res = 0;
            ast_verb(4, "Channel %s was answered.\n", chan->name);
            tmp = ast_calloc(1, sizeof(*tmp));
            if (!tmp)
               res = -1;
            else {
               ast_copy_string(tmp->app, app, sizeof(tmp->app));
               if (appdata)
                  ast_copy_string(tmp->data, appdata, sizeof(tmp->data));
               tmp->chan = chan;
               if (synchronous > 1) {
                  if (locked_channel)
                     ast_channel_unlock(chan);
                  ast_pbx_run_app(tmp);
               } else {
                  if (locked_channel)
                     ast_channel_lock(chan);
                  if (ast_pthread_create_detached(&tmp->t, NULL, ast_pbx_run_app, tmp)) {
                     ast_log(LOG_WARNING, "Unable to spawn execute thread on %s: %s\n", chan->name, strerror(errno));
                     ast_free(tmp);
                     if (locked_channel)
                        ast_channel_unlock(chan);
                     ast_hangup(chan);
                     res = -1;
                  } else {
                     if (locked_channel)
                        *locked_channel = chan;
                  }
               }
            }
         } else {
            ast_verb(4, "Channel %s was never answered.\n", chan->name);
            if (chan->cdr) { /* update the cdr */
               /* here we update the status of the call, which sould be busy.
                * if that fails then we set the status to failed */
               if (ast_cdr_disposition(chan->cdr, chan->hangupcause))
                  ast_cdr_failed(chan->cdr);
            }
            ast_hangup(chan);
         }
      }

      if (res < 0) { /* the call failed for some reason */
         if (*reason == 0) { /* if the call failed (not busy or no answer)
                        * update the cdr with the failed message */
            cdr_res = ast_pbx_outgoing_cdr_failed();
            if (cdr_res != 0) {
               res = cdr_res;
               goto outgoing_app_cleanup;
            }
         }
      }

   } else {
      struct async_stat *as;
      if (!(as = ast_calloc(1, sizeof(*as)))) {
         res = -1;
         goto outgoing_app_cleanup;
      }
      chan = __ast_request_and_dial(type, format, data, timeout, reason, cid_num, cid_name, &oh);
      if (!chan) {
         ast_free(as);
         res = -1;
         goto outgoing_app_cleanup;
      }
      as->chan = chan;
      ast_copy_string(as->app, app, sizeof(as->app));
      if (appdata)
         ast_copy_string(as->appdata,  appdata, sizeof(as->appdata));
      as->timeout = timeout;
      ast_set_variables(chan, vars);
      if (account)
         ast_cdr_setaccount(chan, account);
      /* Start a new thread, and get something handling this channel. */
      if (locked_channel)
         ast_channel_lock(chan);
      if (ast_pthread_create_detached(&as->p, NULL, async_wait, as)) {
         ast_log(LOG_WARNING, "Failed to start async wait\n");
         ast_free(as);
         if (locked_channel)
            ast_channel_unlock(chan);
         ast_hangup(chan);
         res = -1;
         goto outgoing_app_cleanup;
      } else {
         if (locked_channel)
            *locked_channel = chan;
      }
      res = 0;
   }
outgoing_app_cleanup:
   ast_variables_destroy(vars);
   return res;
}

/* this is the guts of destroying a context --
   freeing up the structure, traversing and destroying the
   extensions, switches, ignorepats, includes, etc. etc. */

static void __ast_internal_context_destroy( struct ast_context *con)
{
   struct ast_include *tmpi;
   struct ast_sw *sw;
   struct ast_exten *e, *el, *en;
   struct ast_ignorepat *ipi;
   struct ast_context *tmp = con;
   
   for (tmpi = tmp->includes; tmpi; ) { /* Free includes */
      struct ast_include *tmpil = tmpi;
      tmpi = tmpi->next;
      ast_free(tmpil);
   }
   for (ipi = tmp->ignorepats; ipi; ) { /* Free ignorepats */
      struct ast_ignorepat *ipl = ipi;
      ipi = ipi->next;
      ast_free(ipl);
   }
   if (tmp->registrar)
      ast_free(tmp->registrar);
   
   /* destroy the hash tabs */
   if (tmp->root_table) {
      ast_hashtab_destroy(tmp->root_table, 0);
   }
   /* and destroy the pattern tree */
   if (tmp->pattern_tree)
      destroy_pattern_tree(tmp->pattern_tree);
   
   while ((sw = AST_LIST_REMOVE_HEAD(&tmp->alts, list)))
      ast_free(sw);
   for (e = tmp->root; e;) {
      for (en = e->peer; en;) {
         el = en;
         en = en->peer;
         destroy_exten(el);
      }
      el = e;
      e = e->next;
      destroy_exten(el);
   }
   tmp->root = NULL;
   ast_rwlock_destroy(&tmp->lock);
   ast_free(tmp);
}


void __ast_context_destroy(struct ast_context *list, struct ast_hashtab *contexttab, struct ast_context *con, const char *registrar)
{
   struct ast_context *tmp, *tmpl=NULL;
   struct ast_exten *exten_item, *prio_item;

   for (tmp = list; tmp; ) {
      struct ast_context *next = NULL; /* next starting point */
         /* The following code used to skip forward to the next
            context with matching registrar, but this didn't
            make sense; individual priorities registrar'd to 
            the matching registrar could occur in any context! */
      ast_debug(1, "Investigate ctx %s %s\n", tmp->name, tmp->registrar);
      if (con) {
         for (; tmp; tmpl = tmp, tmp = tmp->next) { /* skip to the matching context */
            ast_debug(1, "check ctx %s %s\n", tmp->name, tmp->registrar);
            if ( !strcasecmp(tmp->name, con->name) ) {
               break;   /* found it */
            }
         }
      }
      
      if (!tmp)   /* not found, we are done */
         break;
      ast_wrlock_context(tmp);

      if (registrar) {
         /* then search thru and remove any extens that match registrar. */
         struct ast_hashtab_iter *exten_iter;
         struct ast_hashtab_iter *prio_iter;
         struct ast_ignorepat *ip, *ipl = NULL, *ipn = NULL;
         struct ast_include *i, *pi = NULL, *ni = NULL;
         struct ast_sw *sw = NULL;

         /* remove any ignorepats whose registrar matches */
         for (ip = tmp->ignorepats; ip; ip = ipn) {
            ipn = ip->next;
            if (!strcmp(ip->registrar, registrar)) {
               if (ipl) {
                  ipl->next = ip->next;
                  ast_free(ip);
                  continue; /* don't change ipl */
               } else {
                  tmp->ignorepats = ip->next;
                  ast_free(ip);
                  continue; /* don't change ipl */
               }
            }
            ipl = ip;
         }
         /* remove any includes whose registrar matches */
         for (i = tmp->includes; i; i = ni) {
            ni = i->next;
            if (strcmp(i->registrar, registrar) == 0) {
               /* remove from list */
               if (pi) {
                  pi->next = i->next;
                  /* free include */
                  ast_free(i);
                  continue; /* don't change pi */
               } else {
                  tmp->includes = i->next;
                  /* free include */
                  ast_free(i);
                  continue; /* don't change pi */
               }
            }
            pi = i;
         }
         /* remove any switches whose registrar matches */
         AST_LIST_TRAVERSE_SAFE_BEGIN(&tmp->alts, sw, list) {
            if (strcmp(sw->registrar,registrar) == 0) {
               AST_LIST_REMOVE_CURRENT(list);
               ast_free(sw);
            }
         }
         AST_LIST_TRAVERSE_SAFE_END;

         if (tmp->root_table) { /* it is entirely possible that the context is EMPTY */
            exten_iter = ast_hashtab_start_traversal(tmp->root_table);
            while ((exten_item=ast_hashtab_next(exten_iter))) {
               prio_iter = ast_hashtab_start_traversal(exten_item->peer_table);
               while ((prio_item=ast_hashtab_next(prio_iter))) {
                  if (!prio_item->registrar || strcmp(prio_item->registrar, registrar) != 0) {
                     continue;
                  }
                  ast_verb(3, "Remove %s/%s/%d, registrar=%s; con=%s(%p); con->root=%p\n",
                         tmp->name, prio_item->exten, prio_item->priority, registrar, con? con->name : "<nil>", con, con? con->root_table: NULL);
                  /* set matchcid to 1 to insure we get a direct match, and NULL registrar to make sure no wildcarding is done */
                  ast_context_remove_extension_callerid2(tmp, prio_item->exten, prio_item->priority, prio_item->cidmatch, 1, NULL, 1);
               }
               ast_hashtab_end_traversal(prio_iter);
            }
            ast_hashtab_end_traversal(exten_iter);
         }
   
         /* delete the context if it's registrar matches, is empty, has refcount of 1, */
         /* it's not empty, if it has includes, ignorepats, or switches that are registered from
            another registrar. It's not empty if there are any extensions */
         if (strcmp(tmp->registrar, registrar) == 0 && tmp->refcount < 2 && !tmp->root && !tmp->ignorepats && !tmp->includes && AST_LIST_EMPTY(&tmp->alts)) {
            ast_debug(1, "delete ctx %s %s\n", tmp->name, tmp->registrar);
            ast_hashtab_remove_this_object(contexttab, tmp);
            
            next = tmp->next;
            if (tmpl)
               tmpl->next = next;
            else
               contexts = next;
            /* Okay, now we're safe to let it go -- in a sense, we were
               ready to let it go as soon as we locked it. */
            ast_unlock_context(tmp);
            __ast_internal_context_destroy(tmp);
         } else {
            ast_debug(1,"Couldn't delete ctx %s/%s; refc=%d; tmp.root=%p\n", tmp->name, tmp->registrar,
                    tmp->refcount, tmp->root);
            ast_unlock_context(tmp);
            next = tmp->next;
            tmpl = tmp;
         }
      } else if (con) {
         ast_verb(3, "Deleting context %s registrar=%s\n", tmp->name, tmp->registrar);
         ast_debug(1, "delete ctx %s %s\n", tmp->name, tmp->registrar);
         ast_hashtab_remove_this_object(contexttab, tmp);
         
         next = tmp->next;
         if (tmpl)
            tmpl->next = next;
         else
            contexts = next;
         /* Okay, now we're safe to let it go -- in a sense, we were
            ready to let it go as soon as we locked it. */
         ast_unlock_context(tmp);
         __ast_internal_context_destroy(tmp);
      }

      /* if we have a specific match, we are done, otherwise continue */
      tmp = con ? NULL : next;
   }
}

void ast_context_destroy(struct ast_context *con, const char *registrar)
{
   ast_wrlock_contexts();
   __ast_context_destroy(contexts, contexts_table, con,registrar);
   ast_unlock_contexts();
}

static void wait_for_hangup(struct ast_channel *chan, void *data)
{
   int res;
   struct ast_frame *f;
   double waitsec;
   int waittime;

   if (ast_strlen_zero(data) || (sscanf(data, "%30lg", &waitsec) != 1) || (waitsec < 0))
      waitsec = -1;
   if (waitsec > -1) {
      waittime = waitsec * 1000.0;
      ast_safe_sleep(chan, waittime);
   } else do {
      res = ast_waitfor(chan, -1);
      if (res < 0)
         return;
      f = ast_read(chan);
      if (f)
         ast_frfree(f);
   } while(f);
}

/*!
 * \ingroup applications
 */
static int pbx_builtin_proceeding(struct ast_channel *chan, void *data)
{
   ast_indicate(chan, AST_CONTROL_PROCEEDING);
   return 0;
}

/*!
 * \ingroup applications
 */
static int pbx_builtin_progress(struct ast_channel *chan, void *data)
{
   ast_indicate(chan, AST_CONTROL_PROGRESS);
   return 0;
}

/*!
 * \ingroup applications
 */
static int pbx_builtin_ringing(struct ast_channel *chan, void *data)
{
   ast_indicate(chan, AST_CONTROL_RINGING);
   return 0;
}

/*!
 * \ingroup applications
 */
static int pbx_builtin_busy(struct ast_channel *chan, void *data)
{
   ast_indicate(chan, AST_CONTROL_BUSY);
   /* Don't change state of an UP channel, just indicate
      busy in audio */
   if (chan->_state != AST_STATE_UP) {
      ast_setstate(chan, AST_STATE_BUSY);
      ast_cdr_busy(chan->cdr);
   }
   wait_for_hangup(chan, data);
   return -1;
}

/*!
 * \ingroup applications
 */
static int pbx_builtin_congestion(struct ast_channel *chan, void *data)
{
   ast_indicate(chan, AST_CONTROL_CONGESTION);
   /* Don't change state of an UP channel, just indicate
      congestion in audio */
   if (chan->_state != AST_STATE_UP)
      ast_setstate(chan, AST_STATE_BUSY);
   wait_for_hangup(chan, data);
   return -1;
}

/*!
 * \ingroup applications
 */
static int pbx_builtin_answer(struct ast_channel *chan, void *data)
{
   int delay = 0;

   if ((chan->_state != AST_STATE_UP) && !ast_strlen_zero(data))
      delay = atoi(data);

   if (delay < 0) {
      delay = 0;
   }

   return __ast_answer(chan, delay, 1);
}

static int pbx_builtin_incomplete(struct ast_channel *chan, void *data)
{
   char *options = data;
   int answer = 1;

   /* Some channels can receive DTMF in unanswered state; some cannot */
   if (!ast_strlen_zero(options) && strchr(options, 'n')) {
      answer = 0;
   }

   /* If the channel is hungup, stop waiting */
   if (ast_check_hangup(chan)) {
      return -1;
   } else if (chan->_state != AST_STATE_UP && answer) {
      __ast_answer(chan, 0, 1);
   }

   return AST_PBX_INCOMPLETE;
}

AST_APP_OPTIONS(resetcdr_opts, {
   AST_APP_OPTION('w', AST_CDR_FLAG_POSTED),
   AST_APP_OPTION('a', AST_CDR_FLAG_LOCKED),
   AST_APP_OPTION('v', AST_CDR_FLAG_KEEP_VARS),
   AST_APP_OPTION('e', AST_CDR_FLAG_POST_ENABLE),
});

/*!
 * \ingroup applications
 */
static int pbx_builtin_resetcdr(struct ast_channel *chan, void *data)
{
   char *args;
   struct ast_flags flags = { 0 };

   if (!ast_strlen_zero(data)) {
      args = ast_strdupa(data);
      ast_app_parse_options(resetcdr_opts, &flags, NULL, args);
   }

   ast_cdr_reset(chan->cdr, &flags);

   return 0;
}

/*!
 * \ingroup applications
 */
static int pbx_builtin_setamaflags(struct ast_channel *chan, void *data)
{
   /* Copy the AMA Flags as specified */
   ast_cdr_setamaflags(chan, data ? data : "");
   return 0;
}

/*!
 * \ingroup applications
 */
static int pbx_builtin_hangup(struct ast_channel *chan, void *data)
{
   if (!ast_strlen_zero(data)) {
      int cause;
      char *endptr;

      if ((cause = ast_str2cause(data)) > -1) {
         chan->hangupcause = cause;
         return -1;
      }
      
      cause = strtol((const char *) data, &endptr, 10);
      if (cause != 0 || (data != endptr)) {
         chan->hangupcause = cause;
         return -1;
      }
         
      ast_log(LOG_WARNING, "Invalid cause given to Hangup(): \"%s\"\n", (char *) data);
   }

   if (!chan->hangupcause) {
      chan->hangupcause = AST_CAUSE_NORMAL_CLEARING;
   }

   return -1;
}

/*!
 * \ingroup applications
 */
static int pbx_builtin_gotoiftime(struct ast_channel *chan, void *data)
{
   char *s, *ts, *branch1, *branch2, *branch;
   struct ast_timing timing;

   if (ast_strlen_zero(data)) {
      ast_log(LOG_WARNING, "GotoIfTime requires an argument:\n  <time range>,<days of week>,<days of month>,<months>?'labeliftrue':'labeliffalse'\n");
      return -1;
   }

   ts = s = ast_strdupa(data);

   /* Separate the Goto path */
   strsep(&ts, "?");
   branch1 = strsep(&ts,":");
   branch2 = strsep(&ts,"");

   /* struct ast_include include contained garbage here, fixed by zeroing it on get_timerange */
   if (ast_build_timing(&timing, s) && ast_check_timing(&timing))
      branch = branch1;
   else
      branch = branch2;

   if (ast_strlen_zero(branch)) {
      ast_debug(1, "Not taking any branch\n");
      return 0;
   }

   return pbx_builtin_goto(chan, branch);
}

/*!
 * \ingroup applications
 */
static int pbx_builtin_execiftime(struct ast_channel *chan, void *data)
{
   char *s, *appname;
   struct ast_timing timing;
   struct ast_app *app;
   static const char *usage = "ExecIfTime requires an argument:\n  <time range>,<days of week>,<days of month>,<months>?<appname>[(<appargs>)]";

   if (ast_strlen_zero(data)) {
      ast_log(LOG_WARNING, "%s\n", usage);
      return -1;
   }

   appname = ast_strdupa(data);

   s = strsep(&appname, "?"); /* Separate the timerange and application name/data */
   if (!appname) {   /* missing application */
      ast_log(LOG_WARNING, "%s\n", usage);
      return -1;
   }

   if (!ast_build_timing(&timing, s)) {
      ast_log(LOG_WARNING, "Invalid Time Spec: %s\nCorrect usage: %s\n", s, usage);
      return -1;
   }

   if (!ast_check_timing(&timing))  /* outside the valid time window, just return */
      return 0;

   /* now split appname(appargs) */
   if ((s = strchr(appname, '('))) {
      char *e;
      *s++ = '\0';
      if ((e = strrchr(s, ')')))
         *e = '\0';
      else
         ast_log(LOG_WARNING, "Failed to find closing parenthesis\n");
   }
      

   if ((app = pbx_findapp(appname))) {
      return pbx_exec(chan, app, S_OR(s, ""));
   } else {
      ast_log(LOG_WARNING, "Cannot locate application %s\n", appname);
      return -1;
   }
}

/*!
 * \ingroup applications
 */
static int pbx_builtin_wait(struct ast_channel *chan, void *data)
{
   double s;
   int ms;

   /* Wait for "n" seconds */
   if (data && (s = atof(data)) > 0.0) {
      ms = s * 1000.0;
      return ast_safe_sleep(chan, ms);
   }
   return 0;
}

/*!
 * \ingroup applications
 */
static int pbx_builtin_waitexten(struct ast_channel *chan, void *data)
{
   int ms, res;
   double s;
   struct ast_flags flags = {0};
   char *opts[1] = { NULL };
   char *parse;
   AST_DECLARE_APP_ARGS(args,
      AST_APP_ARG(timeout);
      AST_APP_ARG(options);
   );

   if (!ast_strlen_zero(data)) {
      parse = ast_strdupa(data);
      AST_STANDARD_APP_ARGS(args, parse);
   } else
      memset(&args, 0, sizeof(args));

   if (args.options)
      ast_app_parse_options(waitexten_opts, &flags, opts, args.options);
   
   if (ast_test_flag(&flags, WAITEXTEN_MOH) && !opts[0] ) {
      ast_log(LOG_WARNING, "The 'm' option has been specified for WaitExten without a class.\n"); 
   } else if (ast_test_flag(&flags, WAITEXTEN_MOH)) {
      ast_indicate_data(chan, AST_CONTROL_HOLD, opts[0], strlen(opts[0]));
   } else if (ast_test_flag(&flags, WAITEXTEN_DIALTONE)) {
      const struct tone_zone_sound *ts = ast_get_indication_tone(chan->zone, "dial");
      if (ts)
         ast_playtones_start(chan, 0, ts->data, 0);
      else
         ast_tonepair_start(chan, 350, 440, 0, 0);
   }
   /* Wait for "n" seconds */
   if (args.timeout && (s = atof(args.timeout)) > 0)
       ms = s * 1000.0;
   else if (chan->pbx)
      ms = chan->pbx->rtimeoutms;
   else
      ms = 10000;

   res = ast_waitfordigit(chan, ms);
   if (!res) {
      if (ast_exists_extension(chan, chan->context, chan->exten, chan->priority + 1, chan->cid.cid_num)) {
         ast_verb(3, "Timeout on %s, continuing...\n", chan->name);
      } else if (chan->_softhangup == AST_SOFTHANGUP_TIMEOUT) {
         ast_verb(3, "Call timeout on %s, checking for 'T'\n", chan->name);
         res = -1;
      } else if (ast_exists_extension(chan, chan->context, "t", 1, chan->cid.cid_num)) {
         ast_verb(3, "Timeout on %s, going to 't'\n", chan->name);
         set_ext_pri(chan, "t", 0); /* 0 will become 1, next time through the loop */
      } else {
         ast_log(LOG_WARNING, "Timeout but no rule 't' in context '%s'\n", chan->context);
         res = -1;
      }
   }

   if (ast_test_flag(&flags, WAITEXTEN_MOH))
      ast_indicate(chan, AST_CONTROL_UNHOLD);
   else if (ast_test_flag(&flags, WAITEXTEN_DIALTONE))
      ast_playtones_stop(chan);

   return res;
}

/*!
 * \ingroup applications
 */
static int pbx_builtin_background(struct ast_channel *chan, void *data)
{
   int res = 0;
   int mres = 0;
   struct ast_flags flags = {0};
   char *parse, exten[2] = "";
   AST_DECLARE_APP_ARGS(args,
      AST_APP_ARG(filename);
      AST_APP_ARG(options);
      AST_APP_ARG(lang);
      AST_APP_ARG(context);
   );

   if (ast_strlen_zero(data)) {
      ast_log(LOG_WARNING, "Background requires an argument (filename)\n");
      return -1;
   }

   parse = ast_strdupa(data);

   AST_STANDARD_APP_ARGS(args, parse);

   if (ast_strlen_zero(args.lang))
      args.lang = (char *)chan->language; /* XXX this is const */

   if (ast_strlen_zero(args.context))
      args.context = chan->context;

   if (args.options) {
      if (!strcasecmp(args.options, "skip"))
         flags.flags = BACKGROUND_SKIP;
      else if (!strcasecmp(args.options, "noanswer"))
         flags.flags = BACKGROUND_NOANSWER;
      else
         ast_app_parse_options(background_opts, &flags, NULL, args.options);
   }

   /* Answer if need be */
   if (chan->_state != AST_STATE_UP) {
      if (ast_test_flag(&flags, BACKGROUND_SKIP)) {
         goto done;
      } else if (!ast_test_flag(&flags, BACKGROUND_NOANSWER)) {
         res = ast_answer(chan);
      }
   }

   if (!res) {
      char *back = args.filename;
      char *front;

      ast_stopstream(chan);      /* Stop anything playing */
      /* Stream the list of files */
      while (!res && (front = strsep(&back, "&")) ) {
         if ( (res = ast_streamfile(chan, front, args.lang)) ) {
            ast_log(LOG_WARNING, "ast_streamfile failed on %s for %s\n", chan->name, (char*)data);
            res = 0;
            mres = 1;
            break;
         }
         if (ast_test_flag(&flags, BACKGROUND_PLAYBACK)) {
            res = ast_waitstream(chan, "");
         } else if (ast_test_flag(&flags, BACKGROUND_MATCHEXTEN)) {
            res = ast_waitstream_exten(chan, args.context);
         } else {
            res = ast_waitstream(chan, AST_DIGIT_ANY);
         }
         ast_stopstream(chan);
      }
   }

   /*
    * If the single digit DTMF is an extension in the specified context, then
    * go there and signal no DTMF.  Otherwise, we should exit with that DTMF.
    * If we're in Macro, we'll exit and seek that DTMF as the beginning of an
    * extension in the Macro's calling context.  If we're not in Macro, then
    * we'll simply seek that extension in the calling context.  Previously,
    * someone complained about the behavior as it related to the interior of a
    * Gosub routine, and the fix (#14011) inadvertently broke FreePBX
    * (#14940).  This change should fix both of these situations, but with the
    * possible incompatibility that if a single digit extension does not exist
    * (but a longer extension COULD have matched), it would have previously
    * gone immediately to the "i" extension, but will now need to wait for a
    * timeout.
    */
   if ((exten[0] = res) && !ast_matchmore_extension(chan, args.context, exten, 1, chan->cid.cid_num)) {
      snprintf(chan->exten, sizeof(chan->exten), "%c", res);
      ast_copy_string(chan->context, args.context, sizeof(chan->context));
      chan->priority = 0;
      res = 0;
   }
done:
   pbx_builtin_setvar_helper(chan, "BACKGROUNDSTATUS", mres ? "FAILED" : "SUCCESS");
   return res;
}

/*! Goto
 * \ingroup applications
 */
static int pbx_builtin_goto(struct ast_channel *chan, void *data)
{
   int res = ast_parseable_goto(chan, data);
   if (!res)
      ast_verb(3, "Goto (%s,%s,%d)\n", chan->context, chan->exten, chan->priority + 1);
   return res;
}


int pbx_builtin_serialize_variables(struct ast_channel *chan, struct ast_str **buf)
{
   struct ast_var_t *variables;
   const char *var, *val;
   int total = 0;

   if (!chan)
      return 0;

   (*buf)->used = 0;
   (*buf)->str[0] = '\0';

   ast_channel_lock(chan);

   AST_LIST_TRAVERSE(&chan->varshead, variables, entries) {
      if ((var = ast_var_name(variables)) && (val = ast_var_value(variables))
         /* && !ast_strlen_zero(var) && !ast_strlen_zero(val) */
         ) {
         if (ast_str_append(buf, 0, "%s=%s\n", var, val) < 0) {
            ast_log(LOG_ERROR, "Data Buffer Size Exceeded!\n");
            break;
         } else
            total++;
      } else
         break;
   }

   ast_channel_unlock(chan);

   return total;
}

const char *pbx_builtin_getvar_helper(struct ast_channel *chan, const char *name)
{
   struct ast_var_t *variables;
   const char *ret = NULL;
   int i;
   struct varshead *places[2] = { NULL, &globals };

   if (!name)
      return NULL;

   if (chan) {
      ast_channel_lock(chan);
      places[0] = &chan->varshead;
   }

   for (i = 0; i < 2; i++) {
      if (!places[i])
         continue;
      if (places[i] == &globals)
         ast_rwlock_rdlock(&globalslock);
      AST_LIST_TRAVERSE(places[i], variables, entries) {
         if (!strcmp(name, ast_var_name(variables))) {
            ret = ast_var_value(variables);
            break;
         }
      }
      if (places[i] == &globals)
         ast_rwlock_unlock(&globalslock);
      if (ret)
         break;
   }

   if (chan)
      ast_channel_unlock(chan);

   return ret;
}

void pbx_builtin_pushvar_helper(struct ast_channel *chan, const char *name, const char *value)
{
   struct ast_var_t *newvariable;
   struct varshead *headp;

   if (name[strlen(name)-1] == ')') {
      char *function = ast_strdupa(name);

      ast_log(LOG_WARNING, "Cannot push a value onto a function\n");
      ast_func_write(chan, function, value);
      return;
   }

   if (chan) {
      ast_channel_lock(chan);
      headp = &chan->varshead;
   } else {
      ast_rwlock_wrlock(&globalslock);
      headp = &globals;
   }

   if (value) {
      if (headp == &globals)
         ast_verb(2, "Setting global variable '%s' to '%s'\n", name, value);
      newvariable = ast_var_assign(name, value);
      AST_LIST_INSERT_HEAD(headp, newvariable, entries);
   }

   if (chan)
      ast_channel_unlock(chan);
   else
      ast_rwlock_unlock(&globalslock);
}

void pbx_builtin_setvar_helper(struct ast_channel *chan, const char *name, const char *value)
{
   struct ast_var_t *newvariable;
   struct varshead *headp;
   const char *nametail = name;

   if (name[strlen(name) - 1] == ')') {
      char *function = ast_strdupa(name);

      ast_func_write(chan, function, value);
      return;
   }

   if (chan) {
      ast_channel_lock(chan);
      headp = &chan->varshead;
   } else {
      ast_rwlock_wrlock(&globalslock);
      headp = &globals;
   }

   /* For comparison purposes, we have to strip leading underscores */
   if (*nametail == '_') {
      nametail++;
      if (*nametail == '_')
         nametail++;
   }

   AST_LIST_TRAVERSE (headp, newvariable, entries) {
      if (strcasecmp(ast_var_name(newvariable), nametail) == 0) {
         /* there is already such a variable, delete it */
         AST_LIST_REMOVE(headp, newvariable, entries);
         ast_var_delete(newvariable);
         break;
      }
   }

   if (value) {
      if (headp == &globals)
         ast_verb(2, "Setting global variable '%s' to '%s'\n", name, value);
      newvariable = ast_var_assign(name, value);
      AST_LIST_INSERT_HEAD(headp, newvariable, entries);
      manager_event(EVENT_FLAG_DIALPLAN, "VarSet", 
         "Channel: %s\r\n"
         "Variable: %s\r\n"
         "Value: %s\r\n"
         "Uniqueid: %s\r\n", 
         chan ? chan->name : "none", name, value, 
         chan ? chan->uniqueid : "none");
   }

   if (chan)
      ast_channel_unlock(chan);
   else
      ast_rwlock_unlock(&globalslock);
}

int pbx_builtin_setvar(struct ast_channel *chan, void *data)
{
   char *name, *value, *mydata;

   if (ast_compat_app_set) {
      return pbx_builtin_setvar_multiple(chan, data);
   }

   if (ast_strlen_zero(data)) {
      ast_log(LOG_WARNING, "Set requires one variable name/value pair.\n");
      return 0;
   }

   mydata = ast_strdupa(data);
   name = strsep(&mydata, "=");
   value = mydata;
   if (strchr(name, ' '))
      ast_log(LOG_WARNING, "Please avoid unnecessary spaces on variables as it may lead to unexpected results ('%s' set to '%s').\n", name, mydata);

   pbx_builtin_setvar_helper(chan, name, value);
   return(0);
}

int pbx_builtin_setvar_multiple(struct ast_channel *chan, void *vdata)
{
   char *data;
   int x;
   AST_DECLARE_APP_ARGS(args,
      AST_APP_ARG(pair)[24];
   );
   AST_DECLARE_APP_ARGS(pair,
      AST_APP_ARG(name);
      AST_APP_ARG(value);
   );

   if (ast_strlen_zero(vdata)) {
      ast_log(LOG_WARNING, "MSet requires at least one variable name/value pair.\n");
      return 0;
   }

   data = ast_strdupa(vdata);
   AST_STANDARD_APP_ARGS(args, data);

   for (x = 0; x < args.argc; x++) {
      AST_NONSTANDARD_APP_ARGS(pair, args.pair[x], '=');
      if (pair.argc == 2) {
         pbx_builtin_setvar_helper(chan, pair.name, pair.value);
         if (strchr(pair.name, ' '))
            ast_log(LOG_WARNING, "Please avoid unnecessary spaces on variables as it may lead to unexpected results ('%s' set to '%s').\n", pair.name, pair.value);
      } else if (!chan) {
         ast_log(LOG_WARNING, "MSet: ignoring entry '%s' with no '='\n", pair.name);
      } else {
         ast_log(LOG_WARNING, "MSet: ignoring entry '%s' with no '=' (in %s@%s:%d\n", pair.name, chan->exten, chan->context, chan->priority);
      }
   }

   return 0;
}

int pbx_builtin_importvar(struct ast_channel *chan, void *data)
{
   char *name;
   char *value;
   char *channel;
   char tmp[VAR_BUF_SIZE];
   static int deprecation_warning = 0;

   if (ast_strlen_zero(data)) {
      ast_log(LOG_WARNING, "Ignoring, since there is no variable to set\n");
      return 0;
   }
   tmp[0] = 0;
   if (!deprecation_warning) {
      ast_log(LOG_WARNING, "ImportVar is deprecated.  Please use Set(varname=${IMPORT(channel,variable)}) instead.\n");
      deprecation_warning = 1;
   }

   value = ast_strdupa(data);
   name = strsep(&value,"=");
   channel = strsep(&value,",");
   if (channel && value && name) { /*! \todo XXX should do !ast_strlen_zero(..) of the args ? */
      struct ast_channel *chan2 = ast_get_channel_by_name_locked(channel);
      if (chan2) {
         char *s = alloca(strlen(value) + 4);
         if (s) {
            sprintf(s, "${%s}", value);
            pbx_substitute_variables_helper(chan2, s, tmp, sizeof(tmp) - 1);
         }
         ast_channel_unlock(chan2);
      }
      pbx_builtin_setvar_helper(chan, name, tmp);
   }

   return(0);
}

static int pbx_builtin_noop(struct ast_channel *chan, void *data)
{
   return 0;
}

void pbx_builtin_clear_globals(void)
{
   struct ast_var_t *vardata;

   ast_rwlock_wrlock(&globalslock);
   while ((vardata = AST_LIST_REMOVE_HEAD(&globals, entries)))
      ast_var_delete(vardata);
   ast_rwlock_unlock(&globalslock);
}

int pbx_checkcondition(const char *condition)
{
   int res;
   if (ast_strlen_zero(condition)) {                /* NULL or empty strings are false */
      return 0;
   } else if (sscanf(condition, "%30d", &res) == 1) { /* Numbers are evaluated for truth */
      return res;
   } else {                                         /* Strings are true */
      return 1;
   }
}

static int pbx_builtin_gotoif(struct ast_channel *chan, void *data)
{
   char *condition, *branch1, *branch2, *branch;
   char *stringp;

   if (ast_strlen_zero(data)) {
      ast_log(LOG_WARNING, "Ignoring, since there is no variable to check\n");
      return 0;
   }

   stringp = ast_strdupa(data);
   condition = strsep(&stringp,"?");
   branch1 = strsep(&stringp,":");
   branch2 = strsep(&stringp,"");
   branch = pbx_checkcondition(condition) ? branch1 : branch2;

   if (ast_strlen_zero(branch)) {
      ast_debug(1, "Not taking any branch\n");
      return 0;
   }

   return pbx_builtin_goto(chan, branch);
}

static int pbx_builtin_saynumber(struct ast_channel *chan, void *data)
{
   char tmp[256];
   char *number = tmp;
   char *options;

   if (ast_strlen_zero(data)) {
      ast_log(LOG_WARNING, "SayNumber requires an argument (number)\n");
      return -1;
   }
   ast_copy_string(tmp, data, sizeof(tmp));
   strsep(&number, ",");
   options = strsep(&number, ",");
   if (options) {
      if ( strcasecmp(options, "f") && strcasecmp(options, "m") &&
         strcasecmp(options, "c") && strcasecmp(options, "n") ) {
         ast_log(LOG_WARNING, "SayNumber gender option is either 'f', 'm', 'c' or 'n'\n");
         return -1;
      }
   }

   if (ast_say_number(chan, atoi(tmp), "", chan->language, options)) {
      ast_log(LOG_WARNING, "We were unable to say the number %s, is it too large?\n", tmp);
   }

   return 0;
}

static int pbx_builtin_saydigits(struct ast_channel *chan, void *data)
{
   int res = 0;

   if (data)
      res = ast_say_digit_str(chan, data, "", chan->language);
   return res;
}

static int pbx_builtin_saycharacters(struct ast_channel *chan, void *data)
{
   int res = 0;

   if (data)
      res = ast_say_character_str(chan, data, "", chan->language);
   return res;
}

static int pbx_builtin_sayphonetic(struct ast_channel *chan, void *data)
{
   int res = 0;

   if (data)
      res = ast_say_phonetic_str(chan, data, "", chan->language);
   return res;
}

static void device_state_cb(const struct ast_event *event, void *unused)
{
   const char *device;
   struct statechange *sc;

   device = ast_event_get_ie_str(event, AST_EVENT_IE_DEVICE);
   if (ast_strlen_zero(device)) {
      ast_log(LOG_ERROR, "Received invalid event that had no device IE\n");
      return;
   }

   if (!(sc = ast_calloc(1, sizeof(*sc) + strlen(device) + 1)))
      return;
   strcpy(sc->dev, device);
   if (ast_taskprocessor_push(device_state_tps, handle_statechange, sc) < 0) {
      ast_free(sc);
   }
}

int load_pbx(void)
{
   int x;

   /* Initialize the PBX */
   ast_verb(1, "Asterisk PBX Core Initializing\n");
   if (!(device_state_tps = ast_taskprocessor_get("pbx-core", 0))) {
      ast_log(LOG_WARNING, "failed to create pbx-core taskprocessor\n");
   }

   ast_verb(1, "Registering builtin applications:\n");
   ast_cli_register_multiple(pbx_cli, sizeof(pbx_cli) / sizeof(struct ast_cli_entry));
   __ast_custom_function_register(&exception_function, NULL);

   /* Register builtin applications */
   for (x = 0; x < sizeof(builtins) / sizeof(struct pbx_builtin); x++) {
      ast_verb(1, "[%s]\n", builtins[x].name);
      if (ast_register_application2(builtins[x].name, builtins[x].execute, builtins[x].synopsis, builtins[x].description, NULL)) {
         ast_log(LOG_ERROR, "Unable to register builtin application '%s'\n", builtins[x].name);
         return -1;
      }
   }
   
   /* Register manager application */
   ast_manager_register2("ShowDialPlan", EVENT_FLAG_CONFIG | EVENT_FLAG_REPORTING, manager_show_dialplan, "List dialplan", mandescr_show_dialplan);

   if (!(device_state_sub = ast_event_subscribe(AST_EVENT_DEVICE_STATE, device_state_cb, NULL,
         AST_EVENT_IE_END))) {
      return -1;
   }

   return 0;
}
static int conlock_wrlock_version = 0;

int ast_wrlock_contexts_version(void)
{
   return conlock_wrlock_version;
}

/*
 * Lock context list functions ...
 */
int ast_wrlock_contexts()
{
   int res = ast_rwlock_wrlock(&conlock);
   if (!res)
      ast_atomic_fetchadd_int(&conlock_wrlock_version, 1);
   return res;
}

int ast_rdlock_contexts()
{
   return ast_rwlock_rdlock(&conlock);
}

int ast_unlock_contexts()
{
   return ast_rwlock_unlock(&conlock);
}

/*
 * Lock context ...
 */
int ast_wrlock_context(struct ast_context *con)
{
   return ast_rwlock_wrlock(&con->lock);
}

int ast_rdlock_context(struct ast_context *con)
{
   return ast_rwlock_rdlock(&con->lock);
}

int ast_unlock_context(struct ast_context *con)
{
   return ast_rwlock_unlock(&con->lock);
}

/*
 * Name functions ...
 */
const char *ast_get_context_name(struct ast_context *con)
{
   return con ? con->name : NULL;
}

struct ast_context *ast_get_extension_context(struct ast_exten *exten)
{
   return exten ? exten->parent : NULL;
}

const char *ast_get_extension_name(struct ast_exten *exten)
{
   return exten ? exten->exten : NULL;
}

const char *ast_get_extension_label(struct ast_exten *exten)
{
   return exten ? exten->label : NULL;
}

const char *ast_get_include_name(struct ast_include *inc)
{
   return inc ? inc->name : NULL;
}

const char *ast_get_ignorepat_name(struct ast_ignorepat *ip)
{
   return ip ? ip->pattern : NULL;
}

int ast_get_extension_priority(struct ast_exten *exten)
{
   return exten ? exten->priority : -1;
}

/*
 * Registrar info functions ...
 */
const char *ast_get_context_registrar(struct ast_context *c)
{
   return c ? c->registrar : NULL;
}

const char *ast_get_extension_registrar(struct ast_exten *e)
{
   return e ? e->registrar : NULL;
}

const char *ast_get_include_registrar(struct ast_include *i)
{
   return i ? i->registrar : NULL;
}

const char *ast_get_ignorepat_registrar(struct ast_ignorepat *ip)
{
   return ip ? ip->registrar : NULL;
}

int ast_get_extension_matchcid(struct ast_exten *e)
{
   return e ? e->matchcid : 0;
}

const char *ast_get_extension_cidmatch(struct ast_exten *e)
{
   return e ? e->cidmatch : NULL;
}

const char *ast_get_extension_app(struct ast_exten *e)
{
   return e ? e->app : NULL;
}

void *ast_get_extension_app_data(struct ast_exten *e)
{
   return e ? e->data : NULL;
}

const char *ast_get_switch_name(struct ast_sw *sw)
{
   return sw ? sw->name : NULL;
}

const char *ast_get_switch_data(struct ast_sw *sw)
{
   return sw ? sw->data : NULL;
}

int ast_get_switch_eval(struct ast_sw *sw)
{
   return sw->eval;
}

const char *ast_get_switch_registrar(struct ast_sw *sw)
{
   return sw ? sw->registrar : NULL;
}

/*
 * Walking functions ...
 */
struct ast_context *ast_walk_contexts(struct ast_context *con)
{
   return con ? con->next : contexts;
}

struct ast_exten *ast_walk_context_extensions(struct ast_context *con,
   struct ast_exten *exten)
{
   if (!exten)
      return con ? con->root : NULL;
   else
      return exten->next;
}

struct ast_sw *ast_walk_context_switches(struct ast_context *con,
   struct ast_sw *sw)
{
   if (!sw)
      return con ? AST_LIST_FIRST(&con->alts) : NULL;
   else
      return AST_LIST_NEXT(sw, list);
}

struct ast_exten *ast_walk_extension_priorities(struct ast_exten *exten,
   struct ast_exten *priority)
{
   return priority ? priority->peer : exten;
}

struct ast_include *ast_walk_context_includes(struct ast_context *con,
   struct ast_include *inc)
{
   if (!inc)
      return con ? con->includes : NULL;
   else
      return inc->next;
}

struct ast_ignorepat *ast_walk_context_ignorepats(struct ast_context *con,
   struct ast_ignorepat *ip)
{
   if (!ip)
      return con ? con->ignorepats : NULL;
   else
      return ip->next;
}

int ast_context_verify_includes(struct ast_context *con)
{
   struct ast_include *inc = NULL;
   int res = 0;

   while ( (inc = ast_walk_context_includes(con, inc)) ) {
      if (ast_context_find(inc->rname))
         continue;

      res = -1;
      ast_log(LOG_WARNING, "Context '%s' tries to include nonexistent context '%s'\n",
         ast_get_context_name(con), inc->rname);
      break;
   }

   return res;
}


static int __ast_goto_if_exists(struct ast_channel *chan, const char *context, const char *exten, int priority, int async)
{
   int (*goto_func)(struct ast_channel *chan, const char *context, const char *exten, int priority);

   if (!chan)
      return -2;

   if (context == NULL)
      context = chan->context;
   if (exten == NULL)
      exten = chan->exten;

   goto_func = (async) ? ast_async_goto : ast_explicit_goto;
   if (ast_exists_extension(chan, context, exten, priority, chan->cid.cid_num))
      return goto_func(chan, context, exten, priority);
   else
      return -3;
}

int ast_goto_if_exists(struct ast_channel *chan, const char* context, const char *exten, int priority)
{
   return __ast_goto_if_exists(chan, context, exten, priority, 0);
}

int ast_async_goto_if_exists(struct ast_channel *chan, const char * context, const char *exten, int priority)
{
   return __ast_goto_if_exists(chan, context, exten, priority, 1);
}

static int pbx_parseable_goto(struct ast_channel *chan, const char *goto_string, int async)
{
   char *exten, *pri, *context;
   char *stringp;
   int ipri;
   int mode = 0;

   if (ast_strlen_zero(goto_string)) {
      ast_log(LOG_WARNING, "Goto requires an argument ([[context,]extension,]priority)\n");
      return -1;
   }
   stringp = ast_strdupa(goto_string);
   context = strsep(&stringp, ","); /* guaranteed non-null */
   exten = strsep(&stringp, ",");
   pri = strsep(&stringp, ",");
   if (!exten) {  /* Only a priority in this one */
      pri = context;
      exten = NULL;
      context = NULL;
   } else if (!pri) {   /* Only an extension and priority in this one */
      pri = exten;
      exten = context;
      context = NULL;
   }
   if (*pri == '+') {
      mode = 1;
      pri++;
   } else if (*pri == '-') {
      mode = -1;
      pri++;
   }
   if (sscanf(pri, "%30d", &ipri) != 1) {
      if ((ipri = ast_findlabel_extension(chan, context ? context : chan->context, exten ? exten : chan->exten,
         pri, chan->cid.cid_num)) < 1) {
         ast_log(LOG_WARNING, "Priority '%s' must be a number > 0, or valid label\n", pri);
         return -1;
      } else
         mode = 0;
   }
   /* At this point we have a priority and maybe an extension and a context */

   if (mode)
      ipri = chan->priority + (ipri * mode);

   if (async)
      ast_async_goto(chan, context, exten, ipri);
   else
      ast_explicit_goto(chan, context, exten, ipri);
   
   return 0;

}

int ast_parseable_goto(struct ast_channel *chan, const char *goto_string)
{
   return pbx_parseable_goto(chan, goto_string, 0);
}

int ast_async_parseable_goto(struct ast_channel *chan, const char *goto_string)
{
   return pbx_parseable_goto(chan, goto_string, 1);
}