c-api.h File Reference

#include <stdio.h>

Go to the source code of this file.

Typedefs
typedef void *	boolexpr_t
	Cookie type for an expression tree node.
Enumerations
enum	bool_operator_t { BOOLSTUFF_VALUE, BOOLSTUFF_AND, BOOLSTUFF_OR, BOOLSTUFF_NOT }
	Possible types of a node. More...
enum	bool_error_t { BOOLSTUFF_OK, BOOLSTUFF_ERR_GARBAGE_AT_END, BOOLSTUFF_ERR_RUNAWAY_PARENTHESIS, BOOLSTUFF_ERR_STRING_EXPECTED }
	Possible error codes returned by the parser. More...
Functions
boolexpr_t	boolstuff_create_value_node (const char *value)
	Creates a node that contains a copy of the designated string as its value.
boolexpr_t	boolstuff_create_operator_node (enum bool_operator_t op, boolexpr_t left, boolexpr_t right)
	Creates a node that represents a boolean operator.
boolexpr_t	boolstuff_parse (const char *expr, size_t *error_index, enum bool_error_t *error_code)
	Parse a textual boolean expression and creates a binary tree.
void	boolstuff_destroy_tree (boolexpr_t root)
	Destroys a tree and all its dynamically allocated nodes.
enum bool_operator_t	boolstuff_get_node_type (boolexpr_t node)
	Returns of type of the node (value or operator).
const char *	boolstuff_get_node_value (boolexpr_t node)
	Returns the value of node that represents a variable.
boolexpr_t	boolstuff_get_left_subtree (boolexpr_t node)
	Returns the root of the left-hand subtree of a node.
boolexpr_t	boolstuff_get_right_subtree (boolexpr_t node)
	Returns the root of the right-hand subtree of a node.
void	boolstuff_set_node_type (boolexpr_t node, enum bool_operator_t op)
	Sets the type of a node.
void	boolstuff_set_left_subtree (boolexpr_t node, boolexpr_t subtree)
	Attaches a subtree as a node's left-hand subtree.
void	boolstuff_set_right_subtree (boolexpr_t node, boolexpr_t subtree)
	Attaches a subtree as this node's right-hand subtree.
void	boolstuff_set_node_value (boolexpr_t node, const char *value)
	Changes the string value of a node.
void	boolstuff_print_tree (FILE *out, boolexpr_t root)
	Prints a boolean expression tree in a file.
char *	boolstuff_print_tree_to_string (boolexpr_t root)
void	boolstuff_free_string (char *s)
	Frees the memory used by a string created by this library.
boolexpr_t	boolstuff_clone_tree (boolexpr_t root)
	Creates a complete copy of a binary tree.
boolexpr_t	boolstuff_get_disjunctive_normal_form (boolexpr_t root)
	Transforms a tree into the Disjunctive Normal Form.
int	boolstuff_is_disjunctive_normal_form (boolexpr_t root)
	Determines if a tree is in Disjunctive Normal Form.
boolexpr_t *	boolstuff_get_dnf_term_roots (boolexpr_t root, size_t *num)
	Returns the terms of a tree in Disjunctive Normal Form.
void	boolstuff_free_node_array (boolexpr_t *array)
	Frees an array returned by boolstuff_get_dnf_term_roots().
void	boolstuff_get_tree_variables (boolexpr_t tree, char ***positivesArray, char ***negativesArray)
void	boolstuff_free_variables_sets (char **positivesArray, char **negativesArray)
	Frees the arrays created by boolstuff_get_tree_variables().

---

Typedef Documentation

typedef void* boolexpr_t

Cookie type for an expression tree node.

The NULL value represents the absence of a node.

---

Enumeration Type Documentation

enum bool_error_t

Possible error codes returned by the parser.

Enumerator:

BOOLSTUFF_OK
BOOLSTUFF_ERR_GARBAGE_AT_END
BOOLSTUFF_ERR_RUNAWAY_PARENTHESIS
BOOLSTUFF_ERR_STRING_EXPECTED

enum bool_operator_t

Possible types of a node.

Enumerator:

BOOLSTUFF_VALUE
BOOLSTUFF_AND
BOOLSTUFF_OR
BOOLSTUFF_NOT

---

Function Documentation

boolexpr_t boolstuff_clone_tree

(

boolexpr_t

root

)

Creates a complete copy of a binary tree.

Parameters:

root

root of the tree to be cloned

Returns:

the root of the cloned tree

boolexpr_t boolstuff_create_operator_node	(	enum bool_operator_t	op,
		boolexpr_t	left,
		boolexpr_t	right
	)

Creates a node that represents a boolean operator.

Parameters:

	op	type of operator
	left	left-hand child to attach to the created node (when creating a node of type BOOLSTUFF_NOT, pass NULL for 'left')
	right	right-hand child to attach to the created node

Returns:

the created node

boolexpr_t boolstuff_create_value_node

(

const char *

value

)

Creates a node that contains a copy of the designated string as its value.

Parameters:

value

string to use as the node value (if NULL, an empty string is used as the node value)

Returns:

the created node

void boolstuff_destroy_tree

(

boolexpr_t

root

)

Destroys a tree and all its dynamically allocated nodes.

Parameters:

root

root of the tree to be destroyed

void boolstuff_free_node_array

(

boolexpr_t *

array

)

Frees an array returned by boolstuff_get_dnf_term_roots().

Parameters:

array

array to be freed (ignored if NULL)

void boolstuff_free_string

(

char *

s

)

Frees the memory used by a string created by this library.

Parameters:

s

the address of the string to be freed

void boolstuff_free_variables_sets	(	char **	positivesArray,
		char **	negativesArray
	)

Frees the arrays created by boolstuff_get_tree_variables().

Parameters:

	positivesArray	array of positive variables values
	negativesArray	array of negative variables values

boolexpr_t boolstuff_get_disjunctive_normal_form

(

boolexpr_t

root

)

Transforms a tree into the Disjunctive Normal Form.

Parameters:

root

root of the tree to transform

Returns:

the new root of the tree

boolexpr_t* boolstuff_get_dnf_term_roots	(	boolexpr_t	root,
		size_t *	num
	)

Returns the terms of a tree in Disjunctive Normal Form.

The tree must be in DNF. The nodes of the returned trees must not be modified. boolstuff_free_node_array() MUST be called afterwards on the returned array pointer to free the allocated memory.

Parameters:

	root	root of the DNF tree of which to return the terms
	num	pointer to a size_t that receives the number of non-null pointers in the returned array (ignored if NULL)

Returns:

an array of the nodes at the root of the DNF terms (a NULL pointer is stored at the end of this array to mark its end)

boolexpr_t boolstuff_get_left_subtree

(

boolexpr_t

node

)

Returns the root of the left-hand subtree of a node.

Parameters:

node

node of which to return the left-hand subtree

Returns:

the node at the root of the left-hand subtree (will be NULL for nodes of types BOOLSTUFF_VALUE or BOOLSTUFF_NOT)

enum bool_operator_t boolstuff_get_node_type

(

boolexpr_t

node

)

Returns of type of the node (value or operator).

Parameters:

node

node of which to return the type

Returns:

the type of the node

const char* boolstuff_get_node_value

(

boolexpr_t

node

)

Returns the value of node that represents a variable.

Parameters:

node

node that must be of type BOOLSTUFF_VALUE

Returns:

a pointer to internal storage that contains the string value of the node

boolexpr_t boolstuff_get_right_subtree

(

boolexpr_t

node

)

Returns the root of the right-hand subtree of a node.

Parameters:

node

node of which to return the right-hand subtree

Returns:

the node at the root of the right-hand subtree (will be NULL for nodes of types BOOLSTUFF_VALUE)

void boolstuff_get_tree_variables	(	boolexpr_t	tree,
		char ***	positivesArray,
		char ***	negativesArray
	)

int boolstuff_is_disjunctive_normal_form

(

boolexpr_t

root

)

Determines if a tree is in Disjunctive Normal Form.

Parameters:

root

root of the tree to examine

Returns:

1 if the tree is in DNF, 0 otherwise

boolexpr_t boolstuff_parse	(	const char *	expr,
		size_t *	error_index,
		enum bool_error_t *	error_code
	)

Parse a textual boolean expression and creates a binary tree.

Parameters:

	expr	boolean expression to parse (must not be NULL)
	error_index	pointer to a size_t that will receive the index in 'expr' where the error was detected (ignored if NULL)
	error_code	pointer to an 'enum bool_error_t' that will receive the error code (ignored if NULL)

Returns:

the created tree, or NULL if an error occurred

void boolstuff_print_tree	(	FILE *	out,
		boolexpr_t	root
	)

Prints a boolean expression tree in a file.

Parameters:

	out	file in which to write the boolean expression
	root	root node of the boolean expression tree to write

char* boolstuff_print_tree_to_string

(

boolexpr_t

root

)

void boolstuff_set_left_subtree	(	boolexpr_t	node,
		boolexpr_t	subtree
	)

Attaches a subtree as a node's left-hand subtree.

Parameters:

	node	node that becomes the parent
	subtree	root of the tree that becomes the left-hand subtree

void boolstuff_set_node_type	(	boolexpr_t	node,
		enum bool_operator_t	op
	)

Sets the type of a node.

Parameters:

	node	node whose type is to be set
	op	new type of this node

void boolstuff_set_node_value	(	boolexpr_t	node,
		const char *	value
	)

Changes the string value of a node.

Parameters:

	node	node whose value is to be changed
	value	string that becomes the node's new value (must not be NULL)

void boolstuff_set_right_subtree	(	boolexpr_t	node,
		boolexpr_t	subtree
	)

Attaches a subtree as this node's right-hand subtree.

Parameters:

	node	node that becomes the parent
	subtree	root of the tree that becomes the right-hand subtree