translate.c File Reference

Translate via the use of pseudo channels. More...

#include "asterisk.h"
#include <sys/time.h>
#include <sys/resource.h>
#include <math.h>
#include "asterisk/lock.h"
#include "asterisk/channel.h"
#include "asterisk/translate.h"
#include "asterisk/module.h"
#include "asterisk/frame.h"
#include "asterisk/sched.h"
#include "asterisk/cli.h"
#include "asterisk/term.h"

Include dependency graph for translate.c:

Go to the source code of this file.

Data Structures
struct	translator_path
Defines
#define	MAX_RECALC   1000
#define	SHOW_TRANS   16
Functions
int	__ast_register_translator (struct ast_translator *t, struct ast_module *mod)
	register codec translator
static	AST_RWLIST_HEAD_STATIC (translators, ast_translator)
	the list of translators
struct ast_frame *	ast_trans_frameout (struct ast_trans_pvt *pvt, int datalen, int samples)
	generic frameout routine. If samples and datalen are 0, take whatever is in pvt and reset them, otherwise take the values in the caller and leave alone the pvt values.
struct ast_frame *	ast_translate (struct ast_trans_pvt *path, struct ast_frame *f, int consume)
	do the actual translation
unsigned int	ast_translate_available_formats (unsigned int dest, unsigned int src)
	Mask off unavailable formats from a format bitmask.
void	ast_translate_frame_freed (struct ast_frame *fr)
	Hint that a frame from a translator has been freed.
unsigned int	ast_translate_path_steps (unsigned int dest, unsigned int src)
	Returns the number of steps required to convert from 'src' to 'dest'.
void	ast_translator_activate (struct ast_translator *t)
	Activate a previously deactivated translator.
int	ast_translator_best_choice (int *dst, int *srcs)
	Calculate our best translator source format, given costs, and a desired destination.
struct ast_trans_pvt *	ast_translator_build_path (int dest, int source)
	Build a chain of translators based upon the given source and dest formats.
void	ast_translator_deactivate (struct ast_translator *t)
	Deactivate a translator.
void	ast_translator_free_path (struct ast_trans_pvt *p)
	Frees a translator path Frees the given translator path structure.
int	ast_unregister_translator (struct ast_translator *t)
	unregister codec translator
static void	calc_cost (struct ast_translator *t, int seconds)
	compute the cost of a single translation step
static struct ast_frame *	default_frameout (struct ast_trans_pvt *pvt)
static void	destroy (struct ast_trans_pvt *pvt)
static int	framein (struct ast_trans_pvt *pvt, struct ast_frame *f)
	framein wrapper, deals with plc and bound checks.
static char *	handle_cli_core_show_translation (struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
static void *	newpvt (struct ast_translator *t)
	Allocate the descriptor, required outbuf space, and possibly also plc and desc.
static force_inline int	powerof (unsigned int d)
	returns the index of the lowest bit set
static void	rebuild_matrix (int samples)
	rebuild a translation matrix.
Variables
static struct ast_cli_entry	cli_translate []
static struct translator_path	tr_matrix [MAX_FORMAT][MAX_FORMAT]
	a matrix that, for any pair of supported formats, indicates the total cost of translation and the first step. The full path can be reconstricted iterating on the matrix until step->dstfmt == desired_format.

---

Detailed Description

Translate via the use of pseudo channels.

Author:

Mark Spencer <markster@digium.com>

Definition in file translate.c.

---

Define Documentation

#define MAX_RECALC   1000

Definition at line 43 of file translate.c.

Referenced by handle_cli_core_show_translation().

#define SHOW_TRANS   16

Referenced by handle_cli_core_show_translation().

---

Function Documentation

int __ast_register_translator	(	struct ast_translator *	t,
		struct ast_module *	mod
	)

register codec translator

Register a translator This registers a codec translator with asterisk.

Definition at line 621 of file translate.c.

References ast_translator::active, ast_cli_register_multiple(), AST_FORMAT_SLINEAR, ast_getformatname(), ast_log(), AST_RWLIST_INSERT_BEFORE_CURRENT, AST_RWLIST_INSERT_HEAD, AST_RWLIST_TRAVERSE_SAFE_BEGIN, AST_RWLIST_TRAVERSE_SAFE_END, AST_RWLIST_UNLOCK, AST_RWLIST_WRLOCK, ast_verb, ast_translator::buf_size, ast_translator::buffer_samples, calc_cost(), COLOR_BLACK, COLOR_MAGENTA, ast_translator::cost, default_frameout(), ast_translator::dstfmt, ast_translator::frameout, LOG_WARNING, MAX_FORMAT, ast_translator::module, ast_translator::name, ast_translator::plc_samples, powerof(), rebuild_matrix(), ast_translator::srcfmt, and term_color().

{
   static int added_cli = 0;
   struct ast_translator *u;
   char tmp[80];

   if (!mod) {
      ast_log(LOG_WARNING, "Missing module pointer, you need to supply one\n");
      return -1;
   }

   if (!t->buf_size) {
      ast_log(LOG_WARNING, "empty buf size, you need to supply one\n");
      return -1;
   }

   t->module = mod;

   t->srcfmt = powerof(t->srcfmt);
   t->dstfmt = powerof(t->dstfmt);
   t->active = 1;

   if (t->srcfmt == -1 || t->dstfmt == -1) {
      ast_log(LOG_WARNING, "Invalid translator path: (%s codec is not valid)\n", t->srcfmt == -1 ? "starting" : "ending");
      return -1;
   }
   if (t->plc_samples) {
      if (t->buffer_samples < t->plc_samples) {
         ast_log(LOG_WARNING, "plc_samples %d buffer_samples %d\n",
            t->plc_samples, t->buffer_samples);
         return -1;
      }
      if (t->dstfmt != powerof(AST_FORMAT_SLINEAR))
         ast_log(LOG_WARNING, "plc_samples %d format %x\n",
            t->plc_samples, t->dstfmt);
   }
   if (t->srcfmt >= MAX_FORMAT) {
      ast_log(LOG_WARNING, "Source format %s is larger than MAX_FORMAT\n", ast_getformatname(t->srcfmt));
      return -1;
   }

   if (t->dstfmt >= MAX_FORMAT) {
      ast_log(LOG_WARNING, "Destination format %s is larger than MAX_FORMAT\n", ast_getformatname(t->dstfmt));
      return -1;
   }

   if (t->buf_size) {
      /*
       * Align buf_size properly, rounding up to the machine-specific
       * alignment for pointers.
       */
      struct _test_align { void *a, *b; } p;
      int align = (char *)&p.b - (char *)&p.a;

      t->buf_size = ((t->buf_size + align - 1) / align) * align;
   }

   if (t->frameout == NULL)
      t->frameout = default_frameout;
  
   calc_cost(t, 1);

   ast_verb(2, "Registered translator '%s' from format %s to %s, cost %d\n",
             term_color(tmp, t->name, COLOR_MAGENTA, COLOR_BLACK, sizeof(tmp)),
             ast_getformatname(1 << t->srcfmt), ast_getformatname(1 << t->dstfmt), t->cost);

   if (!added_cli) {
      ast_cli_register_multiple(cli_translate, sizeof(cli_translate) / sizeof(struct ast_cli_entry));
      added_cli++;
   }

   AST_RWLIST_WRLOCK(&translators);

   /* find any existing translators that provide this same srcfmt/dstfmt,
      and put this one in order based on cost */
   AST_RWLIST_TRAVERSE_SAFE_BEGIN(&translators, u, list) {
      if ((u->srcfmt == t->srcfmt) &&
          (u->dstfmt == t->dstfmt) &&
          (u->cost > t->cost)) {
         AST_RWLIST_INSERT_BEFORE_CURRENT(t, list);
         t = NULL;
      }
   }
   AST_RWLIST_TRAVERSE_SAFE_END;

   /* if no existing translator was found for this format combination,
      add it to the beginning of the list */
   if (t)
      AST_RWLIST_INSERT_HEAD(&translators, t, list);

   rebuild_matrix(0);

   AST_RWLIST_UNLOCK(&translators);

   return 0;
}

static AST_RWLIST_HEAD_STATIC	(	translators	,
		ast_translator
	)			[static]

the list of translators

struct ast_frame* ast_trans_frameout	(	struct ast_trans_pvt *	pvt,
		int	datalen,
		int	samples
	)			[read]

generic frameout routine. If samples and datalen are 0, take whatever is in pvt and reset them, otherwise take the values in the caller and leave alone the pvt values.

generic frameout function

Definition at line 214 of file translate.c.

References AST_FRAME_VOICE, AST_FRFLAG_FROM_TRANSLATOR, AST_FRIENDLY_OFFSET, ast_set_flag, ast_trans_pvt::c, ast_frame::data, ast_trans_pvt::datalen, ast_frame::datalen, ast_translator::dstfmt, ast_trans_pvt::f, f, ast_frame::frametype, ast_frame::mallocd, ast_translator::name, ast_frame::offset, ast_trans_pvt::outbuf, ast_frame::ptr, ast_trans_pvt::samples, ast_frame::samples, ast_frame::src, ast_frame::subclass, and ast_trans_pvt::t.

Referenced by default_frameout(), lintoadpcm_frameout(), lintogsm_frameout(), lintoilbc_frameout(), lintolpc10_frameout(), and lintospeex_frameout().

{
   struct ast_frame *f = &pvt->f;

   if (samples)
      f->samples = samples;
   else {
      if (pvt->samples == 0)
         return NULL;
      f->samples = pvt->samples;
      pvt->samples = 0;
   }
   if (datalen)
      f->datalen = datalen;
   else {
      f->datalen = pvt->datalen;
      pvt->datalen = 0;
   }

   f->frametype = AST_FRAME_VOICE;
   f->subclass = 1 << (pvt->t->dstfmt);
   f->mallocd = 0;
   f->offset = AST_FRIENDLY_OFFSET;
   f->src = pvt->t->name;
   f->data.ptr = pvt->outbuf.c;

   ast_set_flag(f, AST_FRFLAG_FROM_TRANSLATOR);

   return f;
}

struct ast_frame* ast_translate	(	struct ast_trans_pvt *	path,
		struct ast_frame *	f,
		int	consume
	)			[read]

do the actual translation

translates one or more frames Apply an input frame into the translator and receive zero or one output frames. Consume determines whether the original frame should be freed

Definition at line 308 of file translate.c.

References ast_format_rate(), AST_FRAME_CNG, AST_FRFLAG_HAS_TIMING_INFO, ast_frfree, ast_samp2tv(), ast_set2_flag, ast_test_flag, ast_tv(), ast_tvadd(), ast_tveq(), ast_tvnow(), ast_tvsub(), ast_tvzero(), ast_frame::delivery, framein(), ast_frame::frametype, ast_frame::len, len(), ast_trans_pvt::next, ast_trans_pvt::nextin, ast_trans_pvt::nextout, ast_frame::samples, ast_frame::seqno, ast_frame::subclass, and ast_frame::ts.

Referenced by __ast_read(), ast_audiohook_read_frame(), ast_slinfactory_feed(), ast_write(), ast_writestream(), audio_audiohook_write_list(), conf_run(), and process_ast_dsp().

{
   struct ast_trans_pvt *p = path;
   struct ast_frame *out = f;
   struct timeval delivery;
   int has_timing_info;
   long ts;
   long len;
   int seqno;

   has_timing_info = ast_test_flag(f, AST_FRFLAG_HAS_TIMING_INFO);
   ts = f->ts;
   len = f->len;
   seqno = f->seqno;

   /* XXX hmmm... check this below */
   if (!ast_tvzero(f->delivery)) {
      if (!ast_tvzero(path->nextin)) {
         /* Make sure this is in line with what we were expecting */
         if (!ast_tveq(path->nextin, f->delivery)) {
            /* The time has changed between what we expected and this
               most recent time on the new packet.  If we have a
               valid prediction adjust our output time appropriately */
            if (!ast_tvzero(path->nextout)) {
               path->nextout = ast_tvadd(path->nextout,
                          ast_tvsub(f->delivery, path->nextin));
            }
            path->nextin = f->delivery;
         }
      } else {
         /* This is our first pass.  Make sure the timing looks good */
         path->nextin = f->delivery;
         path->nextout = f->delivery;
      }
      /* Predict next incoming sample */
      path->nextin = ast_tvadd(path->nextin, ast_samp2tv(f->samples, ast_format_rate(f->subclass)));
   }
   delivery = f->delivery;
   for ( ; out && p ; p = p->next) {
      framein(p, out);
      if (out != f)
         ast_frfree(out);
      out = p->t->frameout(p);
   }
   if (consume)
      ast_frfree(f);
   if (out == NULL)
      return NULL;
   /* we have a frame, play with times */
   if (!ast_tvzero(delivery)) {
      /* Regenerate prediction after a discontinuity */
      if (ast_tvzero(path->nextout))
         path->nextout = ast_tvnow();

      /* Use next predicted outgoing timestamp */
      out->delivery = path->nextout;
      
      /* Predict next outgoing timestamp from samples in this
         frame. */
      path->nextout = ast_tvadd(path->nextout, ast_samp2tv(out->samples, ast_format_rate(out->subclass)));
   } else {
      out->delivery = ast_tv(0, 0);
      ast_set2_flag(out, has_timing_info, AST_FRFLAG_HAS_TIMING_INFO);
      if (has_timing_info) {
         out->ts = ts;
         out->len = len;
         out->seqno = seqno;
      }
   }
   /* Invalidate prediction if we're entering a silence period */
   if (out->frametype == AST_FRAME_CNG)
      path->nextout = ast_tv(0, 0);
   return out;
}

unsigned int ast_translate_available_formats	(	unsigned int	dest,
		unsigned int	src
	)

Mask off unavailable formats from a format bitmask.

Parameters:

	dest	possible destination formats
	src	source formats

Returns:

the destination formats that are available in the source or translatable

The result will include all formats from 'dest' that are either present in 'src' or translatable from a format present in 'src'.

Note:

Only a single audio format and a single video format can be present in 'src', or the function will produce unexpected results.

Definition at line 830 of file translate.c.

References AST_FORMAT_AUDIO_MASK, AST_FORMAT_VIDEO_MASK, AST_RWLIST_RDLOCK, AST_RWLIST_UNLOCK, powerof(), translator_path::step, and tr_matrix.

Referenced by sip_call().

{
   unsigned int res = dest;
   unsigned int x;
   unsigned int src_audio = src & AST_FORMAT_AUDIO_MASK;
   unsigned int src_video = src & AST_FORMAT_VIDEO_MASK;

   /* if we don't have a source format, we just have to try all
      possible destination formats */
   if (!src)
      return dest;

   /* If we have a source audio format, get its format index */
   if (src_audio)
      src_audio = powerof(src_audio);

   /* If we have a source video format, get its format index */
   if (src_video)
      src_video = powerof(src_video);

   AST_RWLIST_RDLOCK(&translators);

   /* For a given source audio format, traverse the list of
      known audio formats to determine whether there exists
      a translation path from the source format to the
      destination format. */
   for (x = 1; src_audio && (x & AST_FORMAT_AUDIO_MASK); x <<= 1) {
      /* if this is not a desired format, nothing to do */
      if (!(dest & x))
         continue;

      /* if the source is supplying this format, then
         we can leave it in the result */
      if (src & x)
         continue;

      /* if we don't have a translation path from the src
         to this format, remove it from the result */
      if (!tr_matrix[src_audio][powerof(x)].step) {
         res &= ~x;
         continue;
      }

      /* now check the opposite direction */
      if (!tr_matrix[powerof(x)][src_audio].step)
         res &= ~x;
   }

   /* For a given source video format, traverse the list of
      known video formats to determine whether there exists
      a translation path from the source format to the
      destination format. */
   for (; src_video && (x & AST_FORMAT_VIDEO_MASK); x <<= 1) {
      /* if this is not a desired format, nothing to do */
      if (!(dest & x))
         continue;

      /* if the source is supplying this format, then
         we can leave it in the result */
      if (src & x)
         continue;

      /* if we don't have a translation path from the src
         to this format, remove it from the result */
      if (!tr_matrix[src_video][powerof(x)].step) {
         res &= ~x;
         continue;
      }

      /* now check the opposite direction */
      if (!tr_matrix[powerof(x)][src_video].step)
         res &= ~x;
   }

   AST_RWLIST_UNLOCK(&translators);

   return res;
}

void ast_translate_frame_freed

(

struct ast_frame *

fr

)

Hint that a frame from a translator has been freed.

This is sort of a hack. This function gets called when ast_frame_free() gets called on a frame that has the AST_FRFLAG_FROM_TRANSLATOR flag set. This is because it is possible for a translation path to be destroyed while a frame from a translator is still in use. Specifically, this happens if a masquerade happens after a call to ast_read() but before the frame is done being processed, since the frame processing is generally done without the channel lock held.

Returns:

nothing

Definition at line 909 of file translate.c.

References ast_clear_flag, AST_FRFLAG_FROM_TRANSLATOR, destroy(), ast_trans_pvt::destroy, f, and ast_trans_pvt::pvt.

Referenced by __frame_free().

{
   struct ast_trans_pvt *pvt;

   ast_clear_flag(fr, AST_FRFLAG_FROM_TRANSLATOR);

   pvt = (struct ast_trans_pvt *) (((char *) fr) - offsetof(struct ast_trans_pvt, f));

   if (!pvt->destroy)
      return;
   
   destroy(pvt);
}

unsigned int ast_translate_path_steps	(	unsigned int	dest,
		unsigned int	src
	)

Returns the number of steps required to convert from 'src' to 'dest'.

Parameters:

	dest	destination format
	src	source format

Returns:

the number of translation steps required, or -1 if no path is available

Definition at line 808 of file translate.c.

References ast_log(), AST_RWLIST_RDLOCK, AST_RWLIST_UNLOCK, LOG_WARNING, translator_path::multistep, powerof(), and tr_matrix.

Referenced by ast_channel_make_compatible_helper().

{
   unsigned int res = -1;

   /* convert bitwise format numbers into array indices */
   src = powerof(src);
   dest = powerof(dest);

   if (src == -1 || dest == -1) {
      ast_log(LOG_WARNING, "No translator path: (%s codec is not valid)\n", src == -1 ? "starting" : "ending");
      return -1;
   }
   AST_RWLIST_RDLOCK(&translators);

   if (tr_matrix[src][dest].step)
      res = tr_matrix[src][dest].multistep + 1;

   AST_RWLIST_UNLOCK(&translators);

   return res;
}

void ast_translator_activate

(

struct ast_translator *

t

)

Activate a previously deactivated translator.

Parameters:

t

translator to activate

Returns:

nothing

Enables the specified translator for use.

Definition at line 744 of file translate.c.

References ast_translator::active, AST_RWLIST_UNLOCK, AST_RWLIST_WRLOCK, and rebuild_matrix().

{
   AST_RWLIST_WRLOCK(&translators);
   t->active = 1;
   rebuild_matrix(0);
   AST_RWLIST_UNLOCK(&translators);
}

int ast_translator_best_choice	(	int *	dst,
		int *	srcs
	)

Calculate our best translator source format, given costs, and a desired destination.

Chooses the best translation path.

Definition at line 761 of file translate.c.

References AST_FORMAT_AUDIO_MASK, AST_RWLIST_RDLOCK, AST_RWLIST_UNLOCK, translator_path::cost, ast_translator::cost, MAX_AUDIO_FORMAT, translator_path::multistep, and tr_matrix.

Referenced by ast_channel_make_compatible_helper(), ast_request(), iax2_request(), and set_format().

{
   int x,y;
   int best = -1;
   int bestdst = 0;
   int cur, cursrc;
   int besttime = INT_MAX;
   int beststeps = INT_MAX;
   int common = ((*dst) & (*srcs)) & AST_FORMAT_AUDIO_MASK; /* are there common formats ? */

   if (common) { /* yes, pick one and return */
      for (cur = 1, y = 0; y <= MAX_AUDIO_FORMAT; cur <<= 1, y++) {
         if (cur & common) /* guaranteed to find one */
            break;
      }
      /* We are done, this is a common format to both. */
      *srcs = *dst = cur;
      return 0;
   } else { /* No, we will need to translate */
      AST_RWLIST_RDLOCK(&translators);
      for (cur = 1, y = 0; y <= MAX_AUDIO_FORMAT; cur <<= 1, y++) {
         if (! (cur & *dst))
            continue;
         for (cursrc = 1, x = 0; x <= MAX_AUDIO_FORMAT; cursrc <<= 1, x++) {
            if (!(*srcs & cursrc) || !tr_matrix[x][y].step ||
                tr_matrix[x][y].cost >  besttime)
               continue;   /* not existing or no better */
            if (tr_matrix[x][y].cost < besttime ||
                tr_matrix[x][y].multistep < beststeps) {
               /* better than what we have so far */
               best = cursrc;
               bestdst = cur;
               besttime = tr_matrix[x][y].cost;
               beststeps = tr_matrix[x][y].multistep;
            }
         }
      }
      AST_RWLIST_UNLOCK(&translators);
      if (best > -1) {
         *srcs = best;
         *dst = bestdst;
         best = 0;
      }
      return best;
   }
}

struct ast_trans_pvt* ast_translator_build_path	(	int	dest,
		int	source
	)			[read]

Build a chain of translators based upon the given source and dest formats.

Builds a translator path Build a path (possibly NULL) from source to dest.

Definition at line 263 of file translate.c.

References ast_getformatname(), ast_log(), AST_RWLIST_RDLOCK, AST_RWLIST_UNLOCK, ast_translator_free_path(), ast_tv(), ast_translator::dstfmt, LOG_WARNING, newpvt(), ast_trans_pvt::next, ast_trans_pvt::nextin, ast_trans_pvt::nextout, powerof(), translator_path::step, ast_trans_pvt::t, and tr_matrix.

Referenced by ast_audiohook_read_frame(), ast_slinfactory_feed(), ast_writestream(), audio_audiohook_write_list(), conf_run(), misdn_set_opt_exec(), read_config(), and set_format().

{
   struct ast_trans_pvt *head = NULL, *tail = NULL;
   
   source = powerof(source);
   dest = powerof(dest);

   if (source == -1 || dest == -1) {
      ast_log(LOG_WARNING, "No translator path: (%s codec is not valid)\n", source == -1 ? "starting" : "ending");
      return NULL;
   }

   AST_RWLIST_RDLOCK(&translators);

   while (source != dest) {
      struct ast_trans_pvt *cur;
      struct ast_translator *t = tr_matrix[source][dest].step;
      if (!t) {
         ast_log(LOG_WARNING, "No translator path from %s to %s\n", 
            ast_getformatname(source), ast_getformatname(dest));
         AST_RWLIST_UNLOCK(&translators);
         return NULL;
      }
      if (!(cur = newpvt(t))) {
         ast_log(LOG_WARNING, "Failed to build translator step from %d to %d\n", source, dest);
         if (head)
            ast_translator_free_path(head);  
         AST_RWLIST_UNLOCK(&translators);
         return NULL;
      }
      if (!head)
         head = cur;
      else
         tail->next = cur;
      tail = cur;
      cur->nextin = cur->nextout = ast_tv(0, 0);
      /* Keep going if this isn't the final destination */
      source = cur->t->dstfmt;
   }

   AST_RWLIST_UNLOCK(&translators);
   return head;
}

void ast_translator_deactivate

(

struct ast_translator *

t

)

Deactivate a translator.

Parameters:

t

translator to deactivate

Returns:

nothing

Disables the specified translator from being used.

Definition at line 752 of file translate.c.

References ast_translator::active, AST_RWLIST_UNLOCK, AST_RWLIST_WRLOCK, and rebuild_matrix().

{
   AST_RWLIST_WRLOCK(&translators);
   t->active = 0;
   rebuild_matrix(0);
   AST_RWLIST_UNLOCK(&translators);
}

void ast_translator_free_path

(

struct ast_trans_pvt *

tr

)

Frees a translator path Frees the given translator path structure.

Parameters:

tr

translator path to get rid of

Definition at line 253 of file translate.c.

References destroy(), and ast_trans_pvt::next.

Referenced by ast_audiohook_destroy(), ast_audiohook_detach_list(), ast_audiohook_read_frame(), ast_channel_free(), ast_slinfactory_destroy(), ast_slinfactory_feed(), ast_slinfactory_flush(), ast_translator_build_path(), ast_writestream(), audio_audiohook_write_list(), cl_dequeue_chan(), conf_free(), filestream_destructor(), free_translation(), and set_format().

{
   struct ast_trans_pvt *pn = p;
   while ( (p = pn) ) {
      pn = p->next;
      destroy(p);
   }
}

int ast_unregister_translator

(

struct ast_translator *

t

)

unregister codec translator

Unregister a translator Unregisters the given tranlator.

Definition at line 719 of file translate.c.

References ast_getformatname(), AST_RWLIST_REMOVE_CURRENT, AST_RWLIST_TRAVERSE_SAFE_BEGIN, AST_RWLIST_TRAVERSE_SAFE_END, AST_RWLIST_UNLOCK, AST_RWLIST_WRLOCK, ast_verb, COLOR_BLACK, COLOR_MAGENTA, ast_translator::dstfmt, ast_translator::list, ast_translator::name, rebuild_matrix(), ast_translator::srcfmt, and term_color().

Referenced by drop_translator(), load_module(), unload_module(), and unregister_translators().

{
   char tmp[80];
   struct ast_translator *u;
   int found = 0;

   AST_RWLIST_WRLOCK(&translators);
   AST_RWLIST_TRAVERSE_SAFE_BEGIN(&translators, u, list) {
      if (u == t) {
         AST_RWLIST_REMOVE_CURRENT(list);
         ast_verb(2, "Unregistered translator '%s' from format %s to %s\n", term_color(tmp, t->name, COLOR_MAGENTA, COLOR_BLACK, sizeof(tmp)), ast_getformatname(1 << t->srcfmt), ast_getformatname(1 << t->dstfmt));
         found = 1;
         break;
      }
   }
   AST_RWLIST_TRAVERSE_SAFE_END;

   if (found)
      rebuild_matrix(0);

   AST_RWLIST_UNLOCK(&translators);

   return (u ? 0 : -1);
}

static void calc_cost	(	struct ast_translator *	t,
		int	seconds
	)			[static]

compute the cost of a single translation step

Definition at line 384 of file translate.c.

References ast_format_rate(), ast_frfree, ast_log(), ast_translator::cost, destroy(), ast_translator::dstfmt, f, framein(), ast_translator::frameout, LOG_WARNING, ast_translator::name, newpvt(), ast_trans_pvt::pvt, ast_translator::sample, and ast_frame::samples.

Referenced by __ast_register_translator(), and rebuild_matrix().

{
   int num_samples = 0;
   struct ast_trans_pvt *pvt;
   struct rusage start;
   struct rusage end;
   int cost;
   int out_rate = ast_format_rate(t->dstfmt);

   if (!seconds)
      seconds = 1;
   
   /* If they don't make samples, give them a terrible score */
   if (!t->sample) {
      ast_log(LOG_WARNING, "Translator '%s' does not produce sample frames.\n", t->name);
      t->cost = 999999;
      return;
   }

   pvt = newpvt(t);
   if (!pvt) {
      ast_log(LOG_WARNING, "Translator '%s' appears to be broken and will probably fail.\n", t->name);
      t->cost = 999999;
      return;
   }

   getrusage(RUSAGE_SELF, &start);

   /* Call the encoder until we've processed the required number of samples */
   while (num_samples < seconds * out_rate) {
      struct ast_frame *f = t->sample();
      if (!f) {
         ast_log(LOG_WARNING, "Translator '%s' failed to produce a sample frame.\n", t->name);
         destroy(pvt);
         t->cost = 999999;
         return;
      }
      framein(pvt, f);
      ast_frfree(f);
      while ((f = t->frameout(pvt))) {
         num_samples += f->samples;
         ast_frfree(f);
      }
   }

   getrusage(RUSAGE_SELF, &end);

   cost = ((end.ru_utime.tv_sec - start.ru_utime.tv_sec) * 1000000) + end.ru_utime.tv_usec - start.ru_utime.tv_usec;
   cost += ((end.ru_stime.tv_sec - start.ru_stime.tv_sec) * 1000000) + end.ru_stime.tv_usec - start.ru_stime.tv_usec;

   destroy(pvt);

   t->cost = cost / seconds;

   if (!t->cost)
      t->cost = 1;
}

static struct ast_frame* default_frameout

(

struct ast_trans_pvt *

pvt

)

[static, read]

Definition at line 246 of file translate.c.

References ast_trans_frameout().

Referenced by __ast_register_translator().

{
   return ast_trans_frameout(pvt, 0, 0);
}

static void destroy

(

struct ast_trans_pvt *

pvt

)

[static]

Definition at line 133 of file translate.c.

References ast_free, AST_FRFLAG_FROM_TRANSLATOR, ast_module_unref(), ast_test_flag, ast_translator::destroy, ast_trans_pvt::destroy, ast_trans_pvt::f, ast_translator::module, and ast_trans_pvt::t.

Referenced by ast_translate_frame_freed(), ast_translator_free_path(), and calc_cost().

{
   struct ast_translator *t = pvt->t;

   if (ast_test_flag(&pvt->f, AST_FRFLAG_FROM_TRANSLATOR)) {
      /* If this flag is still set, that means that the translation path has
       * been torn down, while we still have a frame out there being used.
       * When ast_frfree() gets called on that frame, this ast_trans_pvt
       * will get destroyed, too. */

      pvt->destroy = 1;

      return;
   }

   if (t->destroy)
      t->destroy(pvt);
   ast_free(pvt);
   ast_module_unref(t->module);
}

static int framein	(	struct ast_trans_pvt *	pvt,
		struct ast_frame *	f
	)			[static]

framein wrapper, deals with plc and bound checks.

Definition at line 155 of file translate.c.

References ast_copy_flags, AST_FRFLAG_HAS_TIMING_INFO, ast_log(), ast_translator::buffer_samples, ast_trans_pvt::datalen, ast_frame::datalen, ast_trans_pvt::f, ast_translator::framein, ast_trans_pvt::i16, ast_frame::len, LOG_WARNING, ast_translator::name, ast_translator::native_plc, ast_trans_pvt::outbuf, ast_trans_pvt::plc, plc_fillin(), plc_rx(), ast_translator::plc_samples, ast_frame::samples, ast_trans_pvt::samples, ast_frame::seqno, ast_trans_pvt::t, and ast_frame::ts.

Referenced by ast_translate(), and calc_cost().

{
   int16_t *dst = pvt->outbuf.i16;
   int ret;
   int samples = pvt->samples;   /* initial value */
   
   /* Copy the last in jb timing info to the pvt */
   ast_copy_flags(&pvt->f, f, AST_FRFLAG_HAS_TIMING_INFO);
   pvt->f.ts = f->ts;
   pvt->f.len = f->len;
   pvt->f.seqno = f->seqno;

   if (f->samples == 0) {
      ast_log(LOG_WARNING, "no samples for %s\n", pvt->t->name);
   }
   if (pvt->t->buffer_samples) { /* do not pass empty frames to callback */
      if (f->datalen == 0) { /* perform PLC with nominal framesize of 20ms/160 samples */
         if (pvt->plc) {
            int l = pvt->t->plc_samples;
            if (pvt->samples + l > pvt->t->buffer_samples) {
               ast_log(LOG_WARNING, "Out of buffer space\n");
               return -1;
            }
            l = plc_fillin(pvt->plc, dst + pvt->samples, l);
            pvt->samples += l;
            pvt->datalen = pvt->samples * 2; /* SLIN has 2bytes for 1sample */
         }
         /* We don't want generic PLC. If the codec has native PLC, then do that */
         if (!pvt->t->native_plc)
            return 0;
      }
      if (pvt->samples + f->samples > pvt->t->buffer_samples) {
         ast_log(LOG_WARNING, "Out of buffer space\n");
         return -1;
      }
   }
   /* we require a framein routine, wouldn't know how to do
    * it otherwise.
    */
   ret = pvt->t->framein(pvt, f);
   /* possibly store data for plc */
   if (!ret && pvt->plc) {
      int l = pvt->t->plc_samples;
      if (pvt->samples < l)
         l = pvt->samples;
      plc_rx(pvt->plc, dst + pvt->samples - l, l);
   }
   /* diagnostic ... */
   if (pvt->samples == samples)
      ast_log(LOG_WARNING, "%s did not update samples %d\n",
         pvt->t->name, pvt->samples);
   return ret;
}

static char* handle_cli_core_show_translation	(	struct ast_cli_entry *	e,
		int	cmd,
		struct ast_cli_args *	a
	)			[static]

Definition at line 518 of file translate.c.

References ast_cli_args::argc, ast_cli_args::argv, ast_cli(), ast_getformatname(), AST_RWLIST_RDLOCK, AST_RWLIST_UNLOCK, AST_RWLIST_WRLOCK, ast_str_alloca, ast_str_append(), ast_str_buffer, ast_str_set(), CLI_GENERATE, CLI_INIT, CLI_SHOWUSAGE, CLI_SUCCESS, ast_cli_entry::command, ast_translator::cost, ast_cli_args::fd, MAX_RECALC, rebuild_matrix(), SHOW_TRANS, tr_matrix, and ast_cli_entry::usage.

{
#define SHOW_TRANS 16
   int x, y, z;
   int curlen = 0, longest = 0, magnitude[SHOW_TRANS] = { 0, };

   switch (cmd) {
   case CLI_INIT:
      e->command = "core show translation [recalc]";
      e->usage =
         "Usage: core show translation [recalc [<recalc seconds>]]\n"
         "       Displays known codec translators and the cost associated\n"
         "       with each conversion.  If the argument 'recalc' is supplied along\n"
         "       with optional number of seconds to test a new test will be performed\n"
         "       as the chart is being displayed.\n";
      return NULL;
   case CLI_GENERATE:
      return NULL;
   }

   if (a->argc > 5)
      return CLI_SHOWUSAGE;

   if (a->argv[3] && !strcasecmp(a->argv[3], "recalc")) {
      z = a->argv[4] ? atoi(a->argv[4]) : 1;

      if (z <= 0) {
         ast_cli(a->fd, "         Recalc must be greater than 0.  Defaulting to 1.\n");
         z = 1;
      }

      if (z > MAX_RECALC) {
         ast_cli(a->fd, "         Maximum limit of recalc exceeded by %d, truncating value to %d\n", z - MAX_RECALC, MAX_RECALC);
         z = MAX_RECALC;
      }
      ast_cli(a->fd, "         Recalculating Codec Translation (number of sample seconds: %d)\n\n", z);
      AST_RWLIST_WRLOCK(&translators);
      rebuild_matrix(z);
      AST_RWLIST_UNLOCK(&translators);
   } else if (a->argc > 3)
      return CLI_SHOWUSAGE;

   AST_RWLIST_RDLOCK(&translators);

   ast_cli(a->fd, "         Translation times between formats (in microseconds) for one second of data\n");
   ast_cli(a->fd, "          Source Format (Rows) Destination Format (Columns)\n\n");
   /* Get the length of the longest (usable?) codec name, so we know how wide the left side should be */
   for (x = 0; x < SHOW_TRANS; x++) {
      curlen = strlen(ast_getformatname(1 << (x)));
      if (curlen > longest)
         longest = curlen;
      for (y = 0; y < SHOW_TRANS; y++) {
         if (tr_matrix[x][y].cost > pow(10, magnitude[x])) {
            magnitude[y] = floor(log10(tr_matrix[x][y].cost));
         }
      }
   }
   for (x = -1; x < SHOW_TRANS; x++) {
      struct ast_str *out = ast_str_alloca(125);
      /*Go ahead and move to next iteration if dealing with an unknown codec*/
      if(x >= 0 && !strcmp(ast_getformatname(1 << (x)), "unknown"))
         continue;
      ast_str_set(&out, -1, " ");
      for (y = -1; y < SHOW_TRANS; y++) {
         /*Go ahead and move to next iteration if dealing with an unknown codec*/
         if (y >= 0 && !strcmp(ast_getformatname(1 << (y)), "unknown"))
            continue;
         if (y >= 0)
            curlen = strlen(ast_getformatname(1 << (y)));
         if (y >= 0 && magnitude[y] + 1 > curlen) {
            curlen = magnitude[y] + 1;
         }
         if (curlen < 5)
            curlen = 5;
         if (x >= 0 && y >= 0 && tr_matrix[x][y].step) {
            /* Actual codec output */
            ast_str_append(&out, -1, "%*d", curlen + 1, tr_matrix[x][y].cost);
         } else if (x == -1 && y >= 0) {
            /* Top row - use a dynamic size */
            ast_str_append(&out, -1, "%*s", curlen + 1, ast_getformatname(1 << (y)) );
         } else if (y == -1 && x >= 0) {
            /* Left column - use a static size. */
            ast_str_append(&out, -1, "%*s", longest, ast_getformatname(1 << (x)) );
         } else if (x >= 0 && y >= 0) {
            /* Codec not supported */
            ast_str_append(&out, -1, "%*s", curlen + 1, "-");
         } else {
            /* Upper left hand corner */
            ast_str_append(&out, -1, "%*s", longest, "");
         }
      }
      ast_str_append(&out, -1, "\n");
      ast_cli(a->fd, "%s", ast_str_buffer(out));
   }
   AST_RWLIST_UNLOCK(&translators);
   return CLI_SUCCESS;
}

static void* newpvt

(

struct ast_translator *

t

)

[static]

Allocate the descriptor, required outbuf space, and possibly also plc and desc.

Definition at line 93 of file translate.c.

References ast_calloc, ast_free, AST_FRIENDLY_OFFSET, ast_module_ref(), ast_translator::buf_size, ast_trans_pvt::c, ast_translator::desc_size, len(), ast_translator::module, ast_translator::newpvt, ast_trans_pvt::outbuf, ast_trans_pvt::plc, ast_translator::plc_samples, ast_trans_pvt::pvt, ast_trans_pvt::t, and ast_translator::useplc.

Referenced by ast_translator_build_path(), and calc_cost().

{
   struct ast_trans_pvt *pvt;
   int len;
   int useplc = t->plc_samples > 0 && t->useplc;   /* cache, because it can change on the fly */
   char *ofs;

   /*
    * compute the required size adding private descriptor,
    * plc, buffer, AST_FRIENDLY_OFFSET.
    */
   len = sizeof(*pvt) + t->desc_size;
   if (useplc)
      len += sizeof(plc_state_t);
   if (t->buf_size)
      len += AST_FRIENDLY_OFFSET + t->buf_size;
   pvt = ast_calloc(1, len);
   if (!pvt)
      return NULL;
   pvt->t = t;
   ofs = (char *)(pvt + 1);   /* pointer to data space */
   if (t->desc_size) {     /* first comes the descriptor */
      pvt->pvt = ofs;
      ofs += t->desc_size;
   }
   if (useplc) {        /* then plc state */
      pvt->plc = (plc_state_t *)ofs;
      ofs += sizeof(plc_state_t);
   }
   if (t->buf_size)     /* finally buffer and header */
      pvt->outbuf.c = ofs + AST_FRIENDLY_OFFSET;
   /* call local init routine, if present */
   if (t->newpvt && t->newpvt(pvt)) {
      ast_free(pvt);
      return NULL;
   }
   ast_module_ref(t->module);
   return pvt;
}

static force_inline int powerof

(

unsigned int

d

)

[static]

returns the index of the lowest bit set

Todo:

TODO: sample frames for each supported input format. We build this on the fly, by taking an SLIN frame and using the existing converter to play with it.

Definition at line 73 of file translate.c.

References ast_log(), and LOG_WARNING.

Referenced by __ast_register_translator(), ast_translate_available_formats(), ast_translate_path_steps(), and ast_translator_build_path().

{
   int x = ffs(d);

   if (x)
      return x - 1;

   ast_log(LOG_WARNING, "No bits set? %d\n", d);

   return -1;
}

static void rebuild_matrix

(

int

samples

)

[static]

rebuild a translation matrix.

Note:

This function expects the list of translators to be locked

Definition at line 446 of file translate.c.

References ast_translator::active, ast_debug, ast_getformatname(), AST_RWLIST_TRAVERSE, calc_cost(), translator_path::cost, ast_translator::cost, ast_translator::dstfmt, ast_translator::list, MAX_FORMAT, translator_path::multistep, ast_translator::srcfmt, translator_path::step, and tr_matrix.

Referenced by __ast_register_translator(), ast_translator_activate(), ast_translator_deactivate(), ast_unregister_translator(), and handle_cli_core_show_translation().

{
   struct ast_translator *t;
   int x;      /* source format index */
   int y;      /* intermediate format index */
   int z;      /* destination format index */

   ast_debug(1, "Resetting translation matrix\n");

   memset(tr_matrix, '\0', sizeof(tr_matrix));

   /* first, compute all direct costs */
   AST_RWLIST_TRAVERSE(&translators, t, list) {
      if (!t->active)
         continue;

      x = t->srcfmt;
      z = t->dstfmt;

      if (samples)
         calc_cost(t, samples);
     
      if (!tr_matrix[x][z].step || t->cost < tr_matrix[x][z].cost) {
         tr_matrix[x][z].step = t;
         tr_matrix[x][z].cost = t->cost;
      }
   }

   /*
    * For each triple x, y, z of distinct formats, check if there is
    * a path from x to z through y which is cheaper than what is
    * currently known, and in case, update the matrix.
    * Repeat until the matrix is stable.
    */
   for (;;) {
      int changed = 0;
      for (x = 0; x < MAX_FORMAT; x++) {      /* source format */
         for (y = 0; y < MAX_FORMAT; y++) {    /* intermediate format */
            if (x == y)                     /* skip ourselves */
               continue;

            for (z = 0; z<MAX_FORMAT; z++) {  /* dst format */
               int newcost;

               if (z == x || z == y)       /* skip null conversions */
                  continue;
               if (!tr_matrix[x][y].step)  /* no path from x to y */
                  continue;
               if (!tr_matrix[y][z].step)  /* no path from y to z */
                  continue;
               newcost = tr_matrix[x][y].cost + tr_matrix[y][z].cost;
               if (tr_matrix[x][z].step && newcost >= tr_matrix[x][z].cost)
                  continue;               /* x->y->z is more expensive than
                                           * the existing path */
               /* ok, we can get from x to z via y with a cost that
                  is the sum of the transition from x to y and
                  from y to z */
                   
               tr_matrix[x][z].step = tr_matrix[x][y].step;
               tr_matrix[x][z].cost = newcost;
               tr_matrix[x][z].multistep = 1;
               ast_debug(3, "Discovered %d cost path from %s to %s, via %s\n", tr_matrix[x][z].cost,
                    ast_getformatname(1 << x), ast_getformatname(1 << z), ast_getformatname(1 << y));
               changed++;
            }
         }
      }
      if (!changed)
         break;
   }
}

---

Variable Documentation

struct ast_cli_entry cli_translate[] [static]

Initial value:

 {

}

Definition at line 616 of file translate.c.

struct translator_path tr_matrix[MAX_FORMAT][MAX_FORMAT] [static]

a matrix that, for any pair of supported formats, indicates the total cost of translation and the first step. The full path can be reconstricted iterating on the matrix until step->dstfmt == desired_format.

Array indexes are 'src' and 'dest', in that order.

Note: the lock in the 'translators' list is also used to protect this structure.

Definition at line 64 of file translate.c.

Referenced by ast_translate_available_formats(), ast_translate_path_steps(), ast_translator_best_choice(), ast_translator_build_path(), handle_cli_core_show_translation(), and rebuild_matrix().