pbx_variables.c File Reference

PBX variables routines. More...

#include "asterisk.h"
#include "asterisk/_private.h"
#include "asterisk/app.h"
#include "asterisk/ast_expr.h"
#include "asterisk/chanvars.h"
#include "asterisk/cli.h"
#include "asterisk/linkedlists.h"
#include "asterisk/lock.h"
#include "asterisk/module.h"
#include "asterisk/paths.h"
#include "asterisk/pbx.h"
#include "asterisk/format_cache.h"
#include "asterisk/stasis_channels.h"
#include "asterisk/test.h"
#include "pbx_private.h"

Include dependency graph for pbx_variables.c:

Go to the source code of this file.

Macros
#define	MAX_VARIABLE_SUB_RECURSE_DEPTH   15

Functions
static void	__init_varsub_recurse_level (void)
	Thread local keeping track of recursion depth. More...
const char *	ast_str_retrieve_variable (struct ast_str **str, ssize_t maxlen, struct ast_channel *c, struct varshead *headp, const char *var)
void	ast_str_substitute_variables (struct ast_str **buf, ssize_t maxlen, struct ast_channel *chan, const char *templ)
void	ast_str_substitute_variables_full (struct ast_str **buf, ssize_t maxlen, struct ast_channel *chan, struct varshead *headp, const char *templ, size_t *used)
void	ast_str_substitute_variables_full2 (struct ast_str **buf, ssize_t maxlen, struct ast_channel *c, struct varshead *headp, const char *templ, size_t *used, int use_both)
	Perform variable/function/expression substitution on an ast_str. More...
void	ast_str_substitute_variables_varshead (struct ast_str **buf, ssize_t maxlen, struct varshead *headp, const char *templ)
static const char *	ast_str_substring (struct ast_str *value, int offset, int length)
static char *	handle_eval_function (struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
	CLI support for executing function. More...
static char *	handle_set_chanvar (struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
static char *	handle_set_global (struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
static char *	handle_show_chanvar (struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
	CLI support for listing chanvar's variables in a parseable way. More...
static char *	handle_show_globals (struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
	CLI support for listing global variables in a parseable way. More...
int	load_pbx_variables (void)
static int	parse_variable_name (char *var, int *offset, int *length, int *isfunc)
	extract offset:length from variable name. More...
void	pbx_builtin_clear_globals (void)
const char *	pbx_builtin_getvar_helper (struct ast_channel *chan, const char *name)
	Return a pointer to the value of the corresponding channel variable. More...
void	pbx_builtin_pushvar_helper (struct ast_channel *chan, const char *name, const char *value)
	Add a variable to the channel variable stack, without removing any previously set value. More...
int	pbx_builtin_serialize_variables (struct ast_channel *chan, struct ast_str **buf)
	Create a human-readable string, specifying all variables and their corresponding values. More...
int	pbx_builtin_setvar (struct ast_channel *chan, const char *data)
	Parse and set a single channel variable, where the name and value are separated with an '=' character. More...
int	pbx_builtin_setvar_helper (struct ast_channel *chan, const char *name, const char *value)
	Add a variable to the channel variable stack, removing the most recently set value for the same name. More...
int	pbx_builtin_setvar_multiple (struct ast_channel *chan, const char *vdata)
	Parse and set multiple channel variables, where the pairs are separated by the ',' character, and name and value are separated with an '=' character. More...
void	pbx_retrieve_variable (struct ast_channel *c, const char *var, char **ret, char *workspace, int workspacelen, struct varshead *headp)
	Support for Asterisk built-in variables in the dialplan. More...
void	pbx_substitute_variables_helper (struct ast_channel *c, const char *cp1, char *cp2, int count)
void	pbx_substitute_variables_helper_full (struct ast_channel *c, struct varshead *headp, const char *cp1, char *cp2, int count, size_t *used)
void	pbx_substitute_variables_helper_full_location (struct ast_channel *c, struct varshead *headp, const char *cp1, char *cp2, int count, size_t *used, const char *context, const char *exten, int pri)
	Substitutes variables, similar to pbx_substitute_variables_helper_full, but allows passing the context, extension, and priority in. More...
void	pbx_substitute_variables_varshead (struct varshead *headp, const char *cp1, char *cp2, int count)
static char *	substring (const char *value, int offset, int length, char *workspace, size_t workspace_len)
	takes a substring. It is ok to call with value == workspace. More...
static void	unload_pbx_variables (void)

Variables
static int	cli_chan = 0
static struct varshead	globals = AST_LIST_HEAD_NOLOCK_INIT_VALUE
static ast_rwlock_t	globalslock = { PTHREAD_RWLOCK_INITIALIZER , NULL, {1, 0} }
static const struct ast_channel_tech	mock_channel_tech
static struct ast_cli_entry	vars_cli []
static struct ast_threadstorage	varsub_recurse_level = { .once = PTHREAD_ONCE_INIT , .key_init = __init_varsub_recurse_level , .custom_init = NULL , }

Detailed Description

PBX variables routines.

Author

Corey Farrell git@c.nosp@m.fwar.nosp@m.e.com

Definition in file pbx_variables.c.

Macro Definition Documentation

MAX_VARIABLE_SUB_RECURSE_DEPTH

#define MAX_VARIABLE_SUB_RECURSE_DEPTH   15

Definition at line 675 of file pbx_variables.c.

Function Documentation

__init_varsub_recurse_level()

static void __init_varsub_recurse_level ( void  )

static

Thread local keeping track of recursion depth.

Definition at line 673 of file pbx_variables.c.

{

ast_str_retrieve_variable()

const char * ast_str_retrieve_variable	(	struct ast_str **	buf,
		ssize_t	maxlen,
		struct ast_channel *	chan,
		struct varshead *	headp,
		const char *	var
	)

Parameters

buf	Result will be placed in this buffer.
maxlen	-1 if the buffer should not grow, 0 if the buffer may grow to any size, and >0 if the buffer should grow only to that number of bytes.
chan	Channel variables from which to extract values, and channel to pass to any dialplan functions.
headp	If no channel is specified, a channel list from which to extract variable values
var	Variable name to retrieve.

Definition at line 257 of file pbx_variables.c.

{
    const char not_found = '\0';
    char *tmpvar;
    const char *ret;
    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 */
    char workspace[20];
 
    if (c) {
        ast_channel_lock(c);
        places[0] = ast_channel_varshead(c);
    }
    /*
     * 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 */
                    ast_str_set(str, maxlen, "%d",
                        ast_party_id_presentation(&ast_channel_caller(c)->id));
                    s = ast_str_buffer(*str);
                } else if (!strcmp(var + 7, "ANI2")) {      /* CALLINGANI2 */
                    ast_str_set(str, maxlen, "%d", ast_channel_caller(c)->ani2);
                    s = ast_str_buffer(*str);
                } else if (!strcmp(var + 7, "TON")) {       /* CALLINGTON */
                    ast_str_set(str, maxlen, "%d", ast_channel_caller(c)->id.number.plan);
                    s = ast_str_buffer(*str);
                } else if (!strcmp(var + 7, "TNS")) {       /* CALLINGTNS */
                    ast_str_set(str, maxlen, "%d", ast_channel_dialed(c)->transit_network_select);
                    s = ast_str_buffer(*str);
                }
            }
        } else if (!strcmp(var, "HINT")) {
            s = ast_str_get_hint(str, maxlen, NULL, 0, c, ast_channel_context(c), ast_channel_exten(c)) ? ast_str_buffer(*str) : NULL;
        } else if (!strcmp(var, "HINTNAME")) {
            s = ast_str_get_hint(NULL, 0, str, maxlen, c, ast_channel_context(c), ast_channel_exten(c)) ? ast_str_buffer(*str) : NULL;
        } else if (!strcmp(var, "EXTEN")) {
            s = ast_channel_exten(c);
        } else if (!strcmp(var, "CONTEXT")) {
            s = ast_channel_context(c);
        } else if (!strcmp(var, "PRIORITY")) {
            ast_str_set(str, maxlen, "%d", ast_channel_priority(c));
            s = ast_str_buffer(*str);
        } else if (!strcmp(var, "CHANNEL")) {
            s = ast_channel_name(c);
        } else if (!strcmp(var, "UNIQUEID")) {
            s = ast_channel_uniqueid(c);
        } else if (!strcmp(var, "HANGUPCAUSE")) {
            ast_str_set(str, maxlen, "%d", ast_channel_hangupcause(c));
            s = ast_str_buffer(*str);
        }
    }
    if (s == &not_found) { /* look for more */
        if (!strcmp(var, "EPOCH")) {
            ast_str_set(str, maxlen, "%d", (int) time(NULL));
            s = ast_str_buffer(*str);
        } else if (!strcmp(var, "SYSTEMNAME")) {
            s = ast_config_AST_SYSTEM_NAME;
        } else if (!strcmp(var, "ASTCACHEDIR")) {
            s = ast_config_AST_CACHE_DIR;
        } else if (!strcmp(var, "ASTETCDIR")) {
            s = ast_config_AST_CONFIG_DIR;
        } else if (!strcmp(var, "ASTMODDIR")) {
            s = ast_config_AST_MODULE_DIR;
        } else if (!strcmp(var, "ASTVARLIBDIR")) {
            s = ast_config_AST_VAR_DIR;
        } else if (!strcmp(var, "ASTDBDIR")) {
            s = ast_config_AST_DB;
        } else if (!strcmp(var, "ASTKEYDIR")) {
            s = ast_config_AST_KEY_DIR;
        } else if (!strcmp(var, "ASTDATADIR")) {
            s = ast_config_AST_DATA_DIR;
        } else if (!strcmp(var, "ASTAGIDIR")) {
            s = ast_config_AST_AGI_DIR;
        } else if (!strcmp(var, "ASTSPOOLDIR")) {
            s = ast_config_AST_SPOOL_DIR;
        } else if (!strcmp(var, "ASTRUNDIR")) {
            s = ast_config_AST_RUN_DIR;
        } else if (!strcmp(var, "ASTLOGDIR")) {
            s = ast_config_AST_LOG_DIR;
        } else if (!strcmp(var, "ASTSBINDIR")) {
            s = ast_config_AST_SBIN_DIR;
        } else if (!strcmp(var, "ENTITYID")) {
            ast_eid_to_str(workspace, sizeof(workspace), &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 (!strcmp(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) {
        ast_debug(5, "Result of '%s' is NULL\n", var);
        ret = NULL;
    } else {
        ast_debug(5, "Result of '%s' is '%s'\n", var, s);
        if (s != ast_str_buffer(*str)) {
            ast_str_set(str, maxlen, "%s", s);
        }
        ret = ast_str_buffer(*str);
        if (need_substring) {
            ret = ast_str_substring(*str, offset, length);
            ast_debug(2, "Final result of '%s' is '%s'\n", var, ret);
        }
    }
 
    if (c) {
        ast_channel_unlock(c);
    }
    return ret;
}

References ARRAY_LEN, ast_channel_caller(), ast_channel_context(), ast_channel_dialed(), ast_channel_exten(), ast_channel_hangupcause(), ast_channel_lock, ast_channel_name(), ast_channel_priority(), ast_channel_uniqueid(), ast_channel_unlock, ast_channel_varshead(), ast_config_AST_AGI_DIR, ast_config_AST_CACHE_DIR, ast_config_AST_CONFIG_DIR, ast_config_AST_DATA_DIR, ast_config_AST_DB, ast_config_AST_KEY_DIR, ast_config_AST_LOG_DIR, ast_config_AST_MODULE_DIR, ast_config_AST_RUN_DIR, ast_config_AST_SBIN_DIR, ast_config_AST_SPOOL_DIR, ast_config_AST_SYSTEM_NAME, ast_config_AST_VAR_DIR, ast_debug, ast_eid_default, ast_eid_to_str(), AST_LIST_TRAVERSE, ast_party_id_presentation(), ast_rwlock_rdlock, ast_rwlock_unlock, ast_str_buffer(), ast_str_get_hint(), ast_str_set(), ast_str_substring(), ast_strdupa, ast_var_name(), ast_var_value(), c, ast_var_t::entries, globals, globalslock, NULL, parse_variable_name(), str, and var.

Referenced by ast_ari_asterisk_get_global_var(), ast_ari_channels_get_channel_var(), ast_str_substitute_variables_full2(), and pbx_retrieve_variable().

ast_str_substitute_variables()

void ast_str_substitute_variables	(	struct ast_str **	buf,
		ssize_t	maxlen,
		struct ast_channel *	chan,
		const char *	templ
	)

Parameters

buf	Result will be placed in this buffer.
maxlen	-1 if the buffer should not grow, 0 if the buffer may grow to any size, and >0 if the buffer should grow only to that number of bytes.
chan	Channel variables from which to extract values, and channel to pass to any dialplan functions.
templ	Variable template to expand.

Definition at line 657 of file pbx_variables.c.

{
    ast_str_substitute_variables_full(buf, maxlen, chan, NULL, templ, NULL);
}

References ast_str_substitute_variables_full(), buf, and NULL.

Referenced by acf_odbc_read(), acf_odbc_write(), ast_pbx_exec_application(), AST_TEST_DEFINE(), cli_odbc_read(), cli_odbc_write(), config_curl(), custom_log(), cut_internal(), destroy_curl(), do_notify(), exec_exec(), func_mchan_read(), function_eval2(), function_fieldnum_helper(), function_fieldqty_helper(), handle_exec(), handle_getvariablefull(), import_helper(), json_decode_read(), listfilter(), make_email_file(), realtime_curl(), realtime_multi_curl(), replace(), require_curl(), sendmail(), sendpage(), shift_pop(), store_curl(), strbetween(), strreplace(), test_2way_function(), test_chan_function(), test_chan_integer(), test_chan_integer_accessor(), test_chan_string(), test_chan_variable(), test_expected_result(), tryexec_exec(), unshift_push(), update2_curl(), and update_curl().

ast_str_substitute_variables_full()

void ast_str_substitute_variables_full	(	struct ast_str **	buf,
		ssize_t	maxlen,
		struct ast_channel *	c,
		struct varshead *	headp,
		const char *	templ,
		size_t *	used
	)

Parameters

buf	Result will be placed in this buffer.
maxlen	-1 if the buffer should not grow, 0 if the buffer may grow to any size, and >0 if the buffer should grow only to that number of bytes.
c	Channel variables from which to extract values, and channel to pass to any dialplan functions.
headp	If no channel is specified, a channel list from which to extract variable values
templ	Variable template to expand.
used	Number of bytes read from the template. (May be NULL)

Definition at line 651 of file pbx_variables.c.

{
    ast_str_substitute_variables_full2(buf, maxlen, chan, headp, templ, used, 0);
}

References ast_str_substitute_variables_full2(), and buf.

Referenced by ast_str_substitute_variables(), and ast_str_substitute_variables_varshead().

ast_str_substitute_variables_full2()

void ast_str_substitute_variables_full2	(	struct ast_str **	buf,
		ssize_t	maxlen,
		struct ast_channel *	c,
		struct varshead *	headp,
		const char *	templ,
		size_t *	used,
		int	use_both
	)

Perform variable/function/expression substitution on an ast_str.

Parameters

buf	Result will be placed in this buffer.
maxlen	-1 if the buffer should not grow, 0 if the buffer may grow to any size, and >0 if the buffer should grow only to that number of bytes.
c	A channel from which to extract values, and to pass to any dialplan functions.
headp	A channel variables list to also search for variables.
templ	Variable template to expand.
used	Number of bytes read from the template. (May be NULL)
use_both	Normally, if a channel is specified, headp is ignored. If this parameter is set to 1 and both a channel and headp are specified, the channel will be searched for variables first and any not found will be searched for in headp.

Definition at line 407 of file pbx_variables.c.

{
    /* Substitutes variables into buf, based on string templ */
    const char *whereweare;
    struct ast_str *substr1 = ast_str_create(16);
    struct ast_str *substr2 = NULL;
    struct ast_str *substr3 = ast_str_create(16);
 
    ast_str_reset(*buf);
 
    if (!substr1 || !substr3) {
        if (used) {
            *used = ast_str_strlen(*buf);
        }
        ast_free(substr1);
        ast_free(substr3);
        return;
    }
 
    whereweare = templ;
    while (!ast_strlen_zero(whereweare)) {
        const char *nextvar = NULL;
        const char *nextexp = NULL;
        const char *nextthing;
        const char *vars;
        const char *vare;
        char *finalvars;
        int pos;
        int brackets;
        int needsub;
        int len;
 
        /* reset our buffer */
        ast_str_reset(substr3);
 
        /* Determine how much simply needs to be copied to the output buf. */
        nextthing = strchr(whereweare, '$');
        if (nextthing) {
            pos = nextthing - whereweare;
            switch (nextthing[1]) {
            case '{':
                /* Variable substitution */
                nextvar = nextthing;
                break;
            case '[':
                /* Expression substitution */
                nextexp = nextthing;
                break;
            default:
                /* '$' is not part of a substitution so include it too. */
                ++pos;
                break;
            }
        } else {
            /* We're copying the whole remaining string */
            pos = strlen(whereweare);
        }
 
        if (pos) {
            /* Copy that many bytes */
            ast_str_append_substr(buf, maxlen, whereweare, pos);
 
            whereweare += pos;
        }
 
        if (nextvar) {
            int offset;
            int offset2;
            int isfunction;
            int res;
 
            /* 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] == '$') && (vare[1] == '{')) {
                    needsub++;
                    brackets++;
                    vare++;
                } else if (vare[0] == '{') {
                    brackets++;
                } else if (vare[0] == '}') {
                    brackets--;
                } else if ((vare[0] == '$') && (vare[1] == '[')) {
                    needsub++;
                    vare++;
                }
                vare++;
            }
            len = vare - vars;
            if (brackets) {
                ast_log(LOG_WARNING, "Error in extension logic (missing '}')\n");
            } else {
                /* Don't count the closing '}' in the length. */
                --len;
            }
 
            /* Skip totally over variable string */
            whereweare = vare;
 
            /* Store variable name expression to lookup. */
            ast_str_set_substr(&substr1, 0, vars, len);
            ast_debug(5, "Evaluating '%s' (from '%s' len %d)\n",
                ast_str_buffer(substr1), vars, len);
 
            /* Substitute if necessary */
            if (needsub) {
                if (!substr2) {
                    substr2 = ast_str_create(16);
                    if (!substr2) {
                        continue;
                    }
                }
                ast_str_substitute_variables_full2(&substr2, 0, c, headp,
                    ast_str_buffer(substr1), NULL, use_both);
                finalvars = ast_str_buffer(substr2);
            } else {
                finalvars = ast_str_buffer(substr1);
            }
 
            parse_variable_name(finalvars, &offset, &offset2, &isfunction);
            if (isfunction) {
                /* Evaluate function */
                res = -1;
                if (c) {
                    res = ast_func_read2(c, finalvars, &substr3, 0);
                    ast_debug(2, "Function %s result is '%s' from channel\n",
                        finalvars, res ? "" : ast_str_buffer(substr3));
                }
                if (!c || (c && res < 0 && use_both)) {
                    struct varshead old;
                    struct ast_channel *bogus;
 
                    bogus = ast_dummy_channel_alloc();
                    if (bogus) {
                        old = *ast_channel_varshead(bogus);
                        if (headp) {
                            *ast_channel_varshead(bogus) = *headp;
                        }
                        res = ast_func_read2(bogus, finalvars, &substr3, 0);
                        /* Don't deallocate the varshead that was passed in */
                        if (headp) {
                            *ast_channel_varshead(bogus) = old;
                        }
                        ast_channel_unref(bogus);
                    } else {
                        ast_log(LOG_ERROR, "Unable to allocate bogus channel for function value substitution.\n");
                        res = -1;
                    }
                    ast_debug(2, "Function %s result is '%s' from headp\n",
                        finalvars, res ? "" : ast_str_buffer(substr3));
                }
            } else {
                const char *result;
                if (c) {
                    result = ast_str_retrieve_variable(&substr3, 0, c, NULL, finalvars);
                    ast_debug(2, "Variable %s result is '%s' from channel\n",
                        finalvars, S_OR(result, ""));
                }
                if (!c || (c && !result && use_both)) {
                    result = ast_str_retrieve_variable(&substr3, 0, NULL, headp, finalvars);
                    ast_debug(2, "Variable %s result is '%s' from headp\n",
                        finalvars, S_OR(result, ""));
                }
                res = (result ? 0 : -1);
            }
            if (!res) {
                ast_str_substring(substr3, offset, offset2);
                ast_str_append(buf, maxlen, "%s", ast_str_buffer(substr3));
            }
        } 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++;
            }
            len = vare - vars;
            if (brackets) {
                ast_log(LOG_WARNING, "Error in extension logic (missing ']')\n");
            } else {
                /* Don't count the closing ']' in the length. */
                --len;
            }
 
            /* Skip totally over expression */
            whereweare = vare;
 
            /* Store expression to evaluate. */
            ast_str_set_substr(&substr1, 0, vars, len);
 
            /* Substitute if necessary */
            if (needsub) {
                if (!substr2) {
                    substr2 = ast_str_create(16);
                    if (!substr2) {
                        continue;
                    }
                }
                ast_str_substitute_variables_full2(&substr2, 0, c, headp,
                    ast_str_buffer(substr1), NULL, use_both);
                finalvars = ast_str_buffer(substr2);
            } else {
                finalvars = ast_str_buffer(substr1);
            }
 
            if (ast_str_expr(&substr3, 0, c, finalvars)) {
                ast_debug(2, "Expression result is '%s'\n", ast_str_buffer(substr3));
            }
            ast_str_append(buf, maxlen, "%s", ast_str_buffer(substr3));
        }
    }
    if (used) {
        *used = ast_str_strlen(*buf);
    }
    ast_free(substr1);
    ast_free(substr2);
    ast_free(substr3);
}

References ast_channel_unref, ast_channel_varshead(), ast_debug, ast_dummy_channel_alloc, ast_free, ast_func_read2(), ast_log, ast_str_append(), ast_str_append_substr(), ast_str_buffer(), ast_str_create, ast_str_expr(), ast_str_reset(), ast_str_retrieve_variable(), ast_str_set_substr(), ast_str_strlen(), ast_str_substitute_variables_full2(), ast_str_substring(), ast_strlen_zero(), buf, c, len(), LOG_ERROR, LOG_WARNING, NULL, parse_variable_name(), result, and S_OR.

Referenced by ast_str_substitute_variables_full(), ast_str_substitute_variables_full2(), and geoloc_eprofile_resolve_varlist().

ast_str_substitute_variables_varshead()

void ast_str_substitute_variables_varshead	(	struct ast_str **	buf,
		ssize_t	maxlen,
		struct varshead *	headp,
		const char *	templ
	)

Parameters

buf	Result will be placed in this buffer.
maxlen	-1 if the buffer should not grow, 0 if the buffer may grow to any size, and >0 if the buffer should grow only to that number of bytes.
headp	If no channel is specified, a channel list from which to extract variable values
templ	Variable template to expand.

Definition at line 662 of file pbx_variables.c.

{
    ast_str_substitute_variables_full(buf, maxlen, NULL, headp, templ, NULL);
}

References ast_str_substitute_variables_full(), buf, and NULL.

Referenced by add_user_extension(), build_user_routes(), handle_aor(), handle_registrations(), phoneprov_callback(), pp_each_extension_helper(), and pp_each_user_helper().

ast_str_substring()

static const char * ast_str_substring ( struct ast_str *  value, int  offset, int  length  )

static

Definition at line 194 of file pbx_variables.c.

{
    int lr; /* length of the input string after the copy */
 
    lr = ast_str_strlen(value); /* compute length after copy, so we never go out of the workspace */
 
    ast_assert(lr == strlen(ast_str_buffer(value))); /* ast_str_strlen should always agree with strlen */
 
    /* Quick check if no need to do anything */
    if (offset == 0 && length >= lr)    /* take the whole string */
        return ast_str_buffer(value);
 
    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) {
        ast_str_reset(value);
        return ast_str_buffer(value);
    }
 
    if (offset > 0) {
        /* Go ahead and chop off the beginning */
        memmove(ast_str_buffer(value), ast_str_buffer(value) + offset, ast_str_strlen(value) - offset + 1);
        lr -= offset;
    }
 
    if (length >= 0 && length < lr) {   /* truncate if necessary */
        ast_str_truncate(value, length);
    } else if (length < 0) {
        if (lr > -length) { /* After we remove from the front and from the rear, is there anything left? */
            ast_str_truncate(value, lr + length);
        } else {
            ast_str_reset(value);
        }
    } else {
        /* Nothing to do, but update the buffer length */
        ast_str_update(value);
    }
 
    return ast_str_buffer(value);
}

References ast_assert, ast_str_buffer(), ast_str_reset(), ast_str_strlen(), ast_str_truncate(), ast_str_update(), and value.

Referenced by ast_str_retrieve_variable(), and ast_str_substitute_variables_full2().

handle_eval_function()

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

static

CLI support for executing function.

Definition at line 994 of file pbx_variables.c.

{
    struct ast_channel *c = NULL;
    const char *fn, *substituted;
    int ret;
    char workspace[1024];
    RAII_VAR(struct ast_format_cap *, caps, NULL, ao2_cleanup);
 
    switch (cmd) {
    case CLI_INIT:
        e->command = "dialplan eval function";
        e->usage =
            "Usage: dialplan eval function <name(args)>\n"
            "       Evaluate a dialplan function call\n"
            "       A dummy channel is used to evaluate\n"
            "       the function call, so only global\n"
            "       variables should be used.\n";
        return NULL;
    case CLI_GENERATE:
        return NULL;
    }
 
    if (a->argc != e->args + 1) {
        return CLI_SHOWUSAGE;
    }
 
    if (a->argc != e->args + 1 && a->argc != e->args + 2) {
        return CLI_SHOWUSAGE;
    }
 
    caps = ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_DEFAULT);
    if (!caps) {
        ast_log(LOG_WARNING, "Could not allocate an empty format capabilities structure\n");
        return CLI_FAILURE;
    }
 
    if (ast_format_cap_append(caps, ast_format_ulaw, 0)) {
        ast_log(LOG_WARNING, "Failed to append a ulaw format to capabilities for channel nativeformats\n");
        return CLI_FAILURE;
    }
 
    if (ast_format_cap_append(caps, ast_format_alaw, 0)) {
        ast_log(LOG_WARNING, "Failed to append an alaw format to capabilities for channel nativeformats\n");
        return CLI_FAILURE;
    }
 
    if (ast_format_cap_append(caps, ast_format_h264, 0)) {
        ast_log(LOG_WARNING, "Failed to append an h264 format to capabilities for channel nativeformats\n");
        return CLI_FAILURE;
    }
 
    c = ast_channel_alloc(0, AST_STATE_DOWN, NULL, NULL, NULL, NULL, NULL, NULL, NULL, 0, "CLIEval/%d", ++cli_chan);
    if (!c) {
        ast_cli(a->fd, "Unable to allocate mock channel for application execution.\n");
        return CLI_FAILURE;
    }
    ast_channel_tech_set(c, &mock_channel_tech);
    ast_channel_nativeformats_set(c, caps);
    ast_channel_set_writeformat(c, ast_format_slin);
    ast_channel_set_rawwriteformat(c, ast_format_slin);
    ast_channel_set_readformat(c, ast_format_slin);
    ast_channel_set_rawreadformat(c, ast_format_slin);
    ast_channel_unlock(c);
 
    fn = a->argv[3];
    pbx_substitute_variables_helper(c, fn, workspace, sizeof(workspace));
    substituted = ast_strdupa(workspace);
    workspace[0] = '\0';
    ret = ast_func_read(c, substituted, workspace, sizeof(workspace));
 
    ast_hangup(c); /* no need to unref separately */
 
    ast_cli(a->fd, "Return Value: %s (%d)\n", ret ? "Failure" : "Success", ret);
    ast_cli(a->fd, "Result: %s\n", workspace);
 
    return CLI_SUCCESS;
}

References a, ao2_cleanup, ast_cli_entry::args, ast_channel_alloc, ast_channel_nativeformats_set(), ast_channel_set_rawreadformat(), ast_channel_set_rawwriteformat(), ast_channel_set_readformat(), ast_channel_set_writeformat(), ast_channel_tech_set(), ast_channel_unlock, ast_cli(), ast_format_alaw, ast_format_cap_alloc, ast_format_cap_append, AST_FORMAT_CAP_FLAG_DEFAULT, ast_format_h264, ast_format_slin, ast_format_ulaw, ast_func_read(), ast_hangup(), ast_log, AST_STATE_DOWN, ast_strdupa, c, cli_chan, CLI_FAILURE, CLI_GENERATE, CLI_INIT, CLI_SHOWUSAGE, CLI_SUCCESS, ast_cli_entry::command, LOG_WARNING, mock_channel_tech, NULL, pbx_substitute_variables_helper(), RAII_VAR, substituted(), and ast_cli_entry::usage.

handle_set_chanvar()

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

static

Definition at line 1094 of file pbx_variables.c.

{
    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_channel_get_by_name(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);
 
    chan = ast_channel_unref(chan);
 
    ast_cli(a->fd, "\n    -- Channel variable '%s' set to '%s' for '%s'\n",  var_name, var_value, chan_name);
 
    return CLI_SUCCESS;
}

References a, ast_cli_entry::args, ast_channel_get_by_name(), ast_channel_unref, ast_cli(), ast_complete_channels(), CLI_FAILURE, CLI_GENERATE, CLI_INIT, CLI_SHOWUSAGE, CLI_SUCCESS, ast_cli_entry::command, NULL, pbx_builtin_setvar_helper(), and ast_cli_entry::usage.

handle_set_global()

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

static

Definition at line 1072 of file pbx_variables.c.

{
    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;
}

References a, ast_cli_entry::args, ast_cli(), CLI_GENERATE, CLI_INIT, CLI_SHOWUSAGE, CLI_SUCCESS, ast_cli_entry::command, NULL, pbx_builtin_setvar_helper(), and ast_cli_entry::usage.

handle_show_chanvar()

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

static

CLI support for listing chanvar's variables in a parseable way.

Definition at line 952 of file pbx_variables.c.

{
    struct ast_channel *chan;
    struct ast_var_t *var;
 
    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;
    }
 
    chan = ast_channel_get_by_name(a->argv[e->args]);
    if (!chan) {
        ast_cli(a->fd, "Channel '%s' not found\n", a->argv[e->args]);
        return CLI_FAILURE;
    }
 
    ast_channel_lock(chan);
    AST_LIST_TRAVERSE(ast_channel_varshead(chan), var, entries) {
        ast_cli(a->fd, "%s=%s\n", ast_var_name(var), ast_var_value(var));
    }
    ast_channel_unlock(chan);
 
    ast_channel_unref(chan);
    return CLI_SUCCESS;
}

References a, ast_cli_entry::args, ast_channel_get_by_name(), ast_channel_lock, ast_channel_unlock, ast_channel_unref, ast_channel_varshead(), ast_cli(), ast_complete_channels(), AST_LIST_TRAVERSE, ast_var_name(), ast_var_value(), CLI_FAILURE, CLI_GENERATE, CLI_INIT, CLI_SHOWUSAGE, CLI_SUCCESS, ast_cli_entry::command, ast_var_t::entries, NULL, ast_cli_entry::usage, and var.

handle_show_globals()

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

static

CLI support for listing global variables in a parseable way.

Definition at line 924 of file pbx_variables.c.

{
    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;
}

References a, ast_cli(), AST_LIST_TRAVERSE, ast_rwlock_rdlock, ast_rwlock_unlock, ast_var_name(), ast_var_value(), CLI_GENERATE, CLI_INIT, CLI_SUCCESS, ast_cli_entry::command, ast_var_t::entries, globals, globalslock, NULL, and ast_cli_entry::usage.

load_pbx_variables()

int load_pbx_variables

(

void

)

Provided by pbx_variables.c

Definition at line 1448 of file pbx_variables.c.

{
    int res = 0;
 
    res |= ast_cli_register_multiple(vars_cli, ARRAY_LEN(vars_cli));
    res |= ast_register_application2("Set", pbx_builtin_setvar, NULL, NULL, NULL);
    res |= ast_register_application2("MSet", pbx_builtin_setvar_multiple, NULL, NULL, NULL);
    ast_register_cleanup(unload_pbx_variables);
    AST_TEST_REGISTER(test_variable_substrings);
 
    return res;
}

References ARRAY_LEN, ast_cli_register_multiple, ast_register_application2(), ast_register_cleanup(), AST_TEST_REGISTER, NULL, pbx_builtin_setvar(), pbx_builtin_setvar_multiple(), unload_pbx_variables(), and vars_cli.

Referenced by asterisk_daemon().

parse_variable_name()

static int parse_variable_name ( char *  var, int *  offset, int *  length, int *  isfunc  )

static

extract offset:length from variable name.

Returns

1 if there is a offset:length part, which is trimmed off (values go into variables)

Definition at line 125 of file pbx_variables.c.

{
    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;
}

References var.

Referenced by ast_str_retrieve_variable(), ast_str_substitute_variables_full2(), and pbx_substitute_variables_helper_full_location().

pbx_builtin_clear_globals()

void pbx_builtin_clear_globals

(

void

)

Definition at line 1353 of file pbx_variables.c.

{
    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);
}

References AST_LIST_REMOVE_HEAD, ast_rwlock_unlock, ast_rwlock_wrlock, ast_var_delete(), ast_var_t::entries, globals, and globalslock.

Referenced by handle_cli_dialplan_reload(), reload(), and unload_pbx_variables().

pbx_builtin_getvar_helper()

const char * pbx_builtin_getvar_helper	(	struct ast_channel *	chan,
		const char *	name
	)

Return a pointer to the value of the corresponding channel variable.

Note

Will lock the channel.

This function will return a pointer to the buffer inside the channel variable. This value should only be accessed with the channel locked. If the value needs to be kept around, it should be done by using the following thread-safe code:

const char *var;
 
ast_channel_lock(chan);
if ((var = pbx_builtin_getvar_helper(chan, "MYVAR"))) {
    var = ast_strdupa(var);
}
ast_channel_unlock(chan);

Definition at line 1162 of file pbx_variables.c.

{
    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] = ast_channel_varshead(chan);
    }
 
    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;
}

References ast_channel_lock, ast_channel_unlock, ast_channel_varshead(), AST_LIST_TRAVERSE, ast_rwlock_rdlock, ast_rwlock_unlock, ast_var_name(), ast_var_value(), globals, globalslock, name, and NULL.

Referenced by __ast_pbx_run(), _while_exec(), action_agents(), add_header_from_channel_var(), agent_handle_show_specific(), agent_login_channel_config(), agent_request_exec(), agent_show_requested(), analog_call(), analog_callwaiting_deluxe(), array(), ast_bridge_add_channel(), ast_bridge_call_with_flags(), ast_bridge_timelimit(), ast_bridge_transfer_attended(), ast_call_forward(), ast_channel_connected_line_sub(), ast_channel_redirecting_sub(), ast_eivr_getvariable(), ast_get_chan_applicationmap(), ast_unreal_hangup(), attended_transfer_exec(), bridge_parking_push(), channel_get_external_vars(), check_bridge_play_sound(), common_exec(), conf_run(), create_dynamic_lot_full(), crement_function_read(), dahdi_hangup(), dial_exec_full(), do_forward(), dundi_exec(), eagi_exec(), eval_sub_read(), feature_automixmonitor(), feature_blind_transfer(), find_by_mark(), find_channel_parking_lot_name(), find_conf_realtime(), func_channel_read(), generate_parked_user(), generic_fax_exec(), get_index(), get_transfer_context(), get_transfer_exten(), global_exists_read(), global_read(), gosub_run(), handle_call_forward(), handle_exec(), handle_gosub(), handle_hangup(), hash_read(), iax2_call(), iax2_exec(), if_helper(), leave_voicemail(), local_read(), manager_mixmonitor(), meetme_menu_admin_extended(), minivm_delete_exec(), minivm_notify_exec(), morsecode_exec(), notify_new_message(), ooh323_call(), ooh323_hangup(), park_app_exec(), pbx_builtin_gotoiftime(), permit_dtmf_interrupt(), pjsip_acf_parse_uri_read(), pre_bridge_setup(), queue_exec(), receive_ademco_event(), refer_blind_callback(), report_receive_fax_status(), report_send_fax_status(), retrydial_exec(), run_agi(), sayunixtime_exec(), sendtext_exec(), set_from_header(), set_touch_variable(), set_transfer_variables_all(), setup_mixmonitor(), setup_park_common_datastore(), sla_trunk_exec(), speech_background(), transfer_refer(), try_calling(), variable_exists_read(), and wait_for_answer().

pbx_builtin_pushvar_helper()

void pbx_builtin_pushvar_helper	(	struct ast_channel *	chan,
		const char *	name,
		const char *	value
	)

Add a variable to the channel variable stack, without removing any previously set value.

Note

Will lock the channel.

Definition at line 1200 of file pbx_variables.c.

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

References ast_channel_lock, ast_channel_unlock, ast_channel_varshead(), ast_func_write(), AST_LIST_INSERT_HEAD, ast_log, ast_rwlock_unlock, ast_rwlock_wrlock, ast_strdupa, ast_var_assign, ast_verb, globals, globalslock, LOG_WARNING, name, and value.

Referenced by acf_odbc_read(), acf_odbc_write(), cli_odbc_read(), cli_odbc_write(), and frame_set_var().

pbx_builtin_serialize_variables()

int pbx_builtin_serialize_variables	(	struct ast_channel *	chan,
		struct ast_str **	buf
	)

Create a human-readable string, specifying all variables and their corresponding values.

Parameters

chan	Channel from which to read variables
buf	Dynamic string in which to place the result (should be allocated with ast_str_create).

See also

ast_str_create

Note

Will lock the channel.

Definition at line 1131 of file pbx_variables.c.

{
    struct ast_var_t *variables;
    const char *var, *val;
    int total = 0;
 
    if (!chan)
        return 0;
 
    ast_str_reset(*buf);
 
    ast_channel_lock(chan);
 
    AST_LIST_TRAVERSE(ast_channel_varshead(chan), 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;
}

References ast_channel_lock, ast_channel_unlock, ast_channel_varshead(), AST_LIST_TRAVERSE, ast_log, ast_str_append(), ast_str_reset(), ast_var_name(), ast_var_value(), buf, ast_var_t::entries, LOG_ERROR, total, and var.

Referenced by ast_var_channels_table(), and dumpchan_exec().

pbx_builtin_setvar()

int pbx_builtin_setvar	(	struct ast_channel *	chan,
		const char *	data
	)

Parse and set a single channel variable, where the name and value are separated with an '=' character.

Note

Will lock the channel.

Definition at line 1291 of file pbx_variables.c.

{
    char *name, *value, *mydata;
 
    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 (!value) {
        ast_log(LOG_WARNING, "Set requires an '=' to be a valid assignment.\n");
        return 0;
    }
 
    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;
}

References ast_log, ast_strdupa, ast_strlen_zero(), LOG_WARNING, name, pbx_builtin_setvar_helper(), strsep(), and value.

Referenced by ast_compile_ael2(), and load_pbx_variables().

pbx_builtin_setvar_helper()

int pbx_builtin_setvar_helper	(	struct ast_channel *	chan,
		const char *	name,
		const char *	value
	)

Add a variable to the channel variable stack, removing the most recently set value for the same name.

Note

Will lock the channel. May also be used to set a channel dialplan function to a particular value.

See also

ast_func_write

Returns

-1 if the dialplan function fails to be set

Version

1.8 changed the function to return an error code

True if the old value was not an empty string.

Definition at line 1233 of file pbx_variables.c.

{
    struct ast_var_t *newvariable;
    struct varshead *headp;
    const char *nametail = name;
    /*! True if the old value was not an empty string. */
    int old_value_existed = 0;
 
    if (name[strlen(name) - 1] == ')') {
        char *function = ast_strdupa(name);
 
        return ast_func_write(chan, function, value);
    }
 
    if (chan) {
        ast_channel_lock(chan);
        headp = ast_channel_varshead(chan);
    } 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_SAFE_BEGIN(headp, newvariable, entries) {
        if (strcmp(ast_var_name(newvariable), nametail) == 0) {
            /* there is already such a variable, delete it */
            AST_LIST_REMOVE_CURRENT(entries);
            old_value_existed = !ast_strlen_zero(ast_var_value(newvariable));
            ast_var_delete(newvariable);
            break;
        }
    }
    AST_LIST_TRAVERSE_SAFE_END;
 
    if (value && (newvariable = ast_var_assign(name, value))) {
        if (headp == &globals) {
            ast_verb(2, "Setting global variable '%s' to '%s'\n", name, value);
        }
        AST_LIST_INSERT_HEAD(headp, newvariable, entries);
        ast_channel_publish_varset(chan, name, value);
    } else if (old_value_existed) {
        /* We just deleted a non-empty dialplan variable. */
        ast_channel_publish_varset(chan, name, "");
    }
 
    if (chan)
        ast_channel_unlock(chan);
    else
        ast_rwlock_unlock(&globalslock);
    return 0;
}

References ast_channel_lock, ast_channel_publish_varset(), ast_channel_unlock, ast_channel_varshead(), ast_func_write(), AST_LIST_INSERT_HEAD, AST_LIST_REMOVE_CURRENT, AST_LIST_TRAVERSE_SAFE_BEGIN, AST_LIST_TRAVERSE_SAFE_END, ast_rwlock_unlock, ast_rwlock_wrlock, ast_strdupa, ast_strlen_zero(), ast_var_assign, ast_var_delete(), ast_var_name(), ast_var_value(), ast_verb, globals, globalslock, name, and value.

Referenced by __analog_ss_thread(), __ast_pbx_run(), _while_exec(), acf_curl_helper(), acf_fetch(), acf_odbc_read(), acf_odbc_write(), acf_transaction_write(), action_atxfer(), action_kick_last(), action_setvar(), admin_exec(), agent_login_exec(), agent_request_exec(), agi_exec_full(), analog_ss_thread(), app_control_set_channel_var(), app_exec(), aqm_exec(), array(), ast_ari_asterisk_set_global_var(), ast_bridge_set_transfer_variables(), ast_bridge_vars_set(), ast_call_forward(), ast_cc_agent_set_interfaces_chanvar(), ast_eivr_setvariable(), ast_iax2_new(), ast_pbx_outgoing_exten_predial(), ast_pickup_call(), ast_rtp_instance_set_stats_vars(), ast_set_cc_interfaces_chanvar(), ast_set_variables(), AST_TEST_DEFINE(), ast_unreal_hangup(), asyncgoto_exec(), attended_transfer_bridge(), attended_transfer_exec(), audiosocket_request(), background_detect_exec(), begin_dial_channel(), blind_transfer_bridge(), blind_transfer_exec(), bridge_channel_internal_push_full(), bridge_exec(), bridgeadd_exec(), calendar_write_exec(), caller_joined_bridge(), caller_safety_timeout(), cccancel_exec(), ccreq_exec(), chan_pjsip_cng_tone_detected(), chan_pjsip_new(), chanavail_exec(), channel_spy(), check_bridge_play_sound(), clear_agent_status(), commit_exec(), conf_run(), confbridge_exec(), confkick_exec(), controlplayback_exec(), count_exec(), crement_function_read(), dahdi_handle_dtmf(), dahdi_new(), delete_write(), dial_exec_full(), dial_transfer(), directory_exec(), disa_exec(), do_directory(), do_forward(), do_notify(), do_waiting(), dtmf_store_framehook(), dynamic_dtmf_hook_callback(), end_bridge_callback(), execute_menu_entry(), fax_detect_framehook(), frame_set_var(), func_export_write(), func_mchan_write(), function_db_delete(), function_db_exists(), function_db_read(), function_realtime_store(), generic_recall(), geoloc_profile_read(), geoloc_profile_write(), global_delete_write(), global_write(), gosub_release_frame(), gosub_run(), handle_controlstreamfile(), handle_gosub(), handle_incoming_request(), handle_outgoing_response(), handle_response_cmgr(), handle_set_chanvar(), handle_set_global(), handle_setvariable(), handle_streamfile(), hash_read(), hash_write(), if_helper(), isAnsweringMachine(), kick_conference_participant(), launch_monitor_thread(), leave_marked(), leave_queue(), leave_voicemail(), lua_set_variable(), lua_set_variable_value(), manager_park(), mbl_status_exec(), minivm_accmess_exec(), minivm_delete_exec(), minivm_greet_exec(), minivm_notify_exec(), minivm_record_exec(), mixmonitor_exec(), msg_send_exec(), my_get_callerid(), my_handle_dtmf(), onModeChanged(), ooh323_new(), ooh323_rtp_read(), originate_exec(), parking_duration_callback(), parking_timeout_set_caller_features(), pbx_builtin_background(), pbx_builtin_gotoiftime(), pbx_builtin_setvar(), pbx_builtin_setvar_multiple(), pbx_builtin_waitdigit(), pbx_load_config(), play_message_datetime(), playback_exec(), pqm_exec(), prep_email_sub_vars(), privacy_exec(), queue_exec(), read_exec(), read_mf_digits(), read_mf_exec(), read_sf_digits(), read_sf_exec(), readexten_exec(), realtimefield_read(), receivefax_exec(), record_abandoned(), record_exec(), recvtext_exec(), refer_blind_callback(), reload_exec(), reload_module(), return_exec(), ring_entry(), rollback_exec(), rotate_file(), rqm_exec(), scan_exec(), select_entry(), select_item_menu(), select_item_seq(), sendfax_exec(), sendtext_exec(), set(), set_channel_variables(), set_duration_var(), set_queue_result(), set_sipdomain_variable(), shift_pop(), signal_exec(), sla_calc_trunk_timeouts(), sla_station_exec(), sla_trunk_exec(), speech_create(), start_automixmonitor(), system_exec_helper(), test_chan_variable(), testtime_write(), transfer_exec(), tryexec_exec(), unicast_rtp_request(), unshift_push(), update_qe_rule(), upqm_exec(), user_timeout(), vm_exec(), vm_playmsgexec(), vmauthenticate(), wait_exec(), wait_for_answer(), wait_for_signal_or_hangup(), waitforcond_exec(), waitsignal_exec(), waituntil_exec(), and zapateller_exec().

pbx_builtin_setvar_multiple()

int pbx_builtin_setvar_multiple	(	struct ast_channel *	chan,
		const char *	data
	)

Parse and set multiple channel variables, where the pairs are separated by the ',' character, and name and value are separated with an '=' character.

Note

Will lock the channel.

Definition at line 1317 of file pbx_variables.c.

{
    char *data;
    int x;
    AST_DECLARE_APP_ARGS(args,
        AST_APP_ARG(pair)[99]; /* parse up to 99 variables */
    );
    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, ast_channel_exten(chan), ast_channel_context(chan), ast_channel_priority(chan));
        }
    }
 
    return 0;
}

References args, AST_APP_ARG, ast_channel_context(), ast_channel_exten(), ast_channel_priority(), AST_DECLARE_APP_ARGS, ast_log, AST_NONSTANDARD_APP_ARGS, AST_STANDARD_APP_ARGS, ast_strdupa, ast_strlen_zero(), LOG_WARNING, name, pair::name, pbx_builtin_setvar_helper(), and value.

Referenced by load_pbx_variables(), queue_function_var(), set_queue_variables(), and try_calling().

pbx_retrieve_variable()

void pbx_retrieve_variable	(	struct ast_channel *	c,
		const char *	var,
		char **	ret,
		char *	workspace,
		int	workspacelen,
		struct varshead *	headp
	)

Support for Asterisk built-in variables in the dialplan.

Retrieve the value of a builtin variable or variable from the channel variable stack.

Note

See also

• Globally predefined channel variables Channel variables
• Hangup Causes for Asterisk The HANGUPCAUSE variable

Definition at line 246 of file pbx_variables.c.

{
    struct ast_str *str = ast_str_create(16);
    const char *cret;
 
    cret = ast_str_retrieve_variable(&str, 0, c, headp, var);
    ast_copy_string(workspace, ast_str_buffer(str), workspacelen);
    *ret = cret ? workspace : NULL;
    ast_free(str);
}

References ast_copy_string(), ast_free, ast_str_buffer(), ast_str_create, ast_str_retrieve_variable(), c, NULL, str, and var.

Referenced by action_getvar(), generate_status(), handle_getvariable(), lua_get_variable(), lua_get_variable_value(), and pbx_substitute_variables_helper_full_location().

pbx_substitute_variables_helper()

void pbx_substitute_variables_helper	(	struct ast_channel *	c,
		const char *	cp1,
		char *	cp2,
		int	count
	)

Definition at line 913 of file pbx_variables.c.

{
    pbx_substitute_variables_helper_full(c, (c) ? ast_channel_varshead(c) : NULL, cp1, cp2, count, NULL);
}

References ast_channel_varshead(), c, NULL, and pbx_substitute_variables_helper_full().

Referenced by handle_eval_function().

pbx_substitute_variables_helper_full()

void pbx_substitute_variables_helper_full	(	struct ast_channel *	c,
		struct varshead *	headp,
		const char *	cp1,
		char *	cp2,
		int	count,
		size_t *	used
	)

Definition at line 667 of file pbx_variables.c.

{
    pbx_substitute_variables_helper_full_location(c, headp, cp1, cp2, count, used, NULL, NULL, 0);
}

References c, NULL, and pbx_substitute_variables_helper_full_location().

Referenced by pbx_substitute_variables_helper(), and pbx_substitute_variables_varshead().

pbx_substitute_variables_helper_full_location()

void pbx_substitute_variables_helper_full_location	(	struct ast_channel *	c,
		struct varshead *	headp,
		const char *	cp1,
		char *	cp2,
		int	count,
		size_t *	used,
		const char *	context,
		const char *	exten,
		int	pri
	)

Substitutes variables, similar to pbx_substitute_variables_helper_full, but allows passing the context, extension, and priority in.

Definition at line 677 of file pbx_variables.c.

{
    /* Substitutes variables into cp2, based on string cp1, cp2 NO LONGER NEEDS TO BE ZEROED OUT!!!!  */
    const char *whereweare;
    const char *orig_cp2 = cp2;
    char ltmp[VAR_BUF_SIZE];
    char var[VAR_BUF_SIZE];
    int *recurse_depth;
 
    *cp2 = 0; /* just in case nothing ends up there */
 
    /* It is possible to craft dialplan that will recurse indefinitely and cause a stack overflow.
     * This is symptomatic of a dialplan bug, so abort substitution rather than crash. */
    recurse_depth = ast_threadstorage_get(&varsub_recurse_level, sizeof(*recurse_depth));
    if (!recurse_depth) {
        return;
    }
    if ((*recurse_depth)++ >= MAX_VARIABLE_SUB_RECURSE_DEPTH) {
        ast_log(LOG_ERROR, "Exceeded maximum variable substitution recursion depth (%d) - possible infinite recursion in dialplan?\n", MAX_VARIABLE_SUB_RECURSE_DEPTH);
        (*recurse_depth)--;
        return;
    }
 
    whereweare = cp1;
    while (!ast_strlen_zero(whereweare) && count) {
        char *nextvar = NULL;
        char *nextexp = NULL;
        char *nextthing;
        char *vars;
        char *vare;
        int length;
        int pos;
        int brackets;
        int needsub;
        int len;
 
        /* Determine how much simply needs to be copied to the output buf. */
        nextthing = strchr(whereweare, '$');
        if (nextthing) {
            pos = nextthing - whereweare;
            switch (nextthing[1]) {
            case '{':
                /* Variable substitution */
                nextvar = nextthing;
                break;
            case '[':
                /* Expression substitution */
                nextexp = nextthing;
                break;
            default:
                /* '$' is not part of a substitution so include it too. */
                ++pos;
                break;
            }
        } else {
            /* We're copying the whole remaining string */
            pos = strlen(whereweare);
        }
 
        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) {
            int offset;
            int offset2;
            int isfunction;
            char *cp4 = NULL;
            char workspace[VAR_BUF_SIZE] = "";
 
            /* 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] == '$') && (vare[1] == '{')) {
                    needsub++;
                    brackets++;
                    vare++;
                } else if (vare[0] == '{') {
                    brackets++;
                } else if (vare[0] == '}') {
                    brackets--;
                } else if ((vare[0] == '$') && (vare[1] == '[')) {
                    needsub++;
                    vare++;
                }
                vare++;
            }
            len = vare - vars;
            if (brackets) {
                ast_log(LOG_WARNING, "Error in extension logic (missing '}')\n");
            } else {
                /* Don't count the closing '}' in the length. */
                --len;
            }
 
            /* Skip totally over variable string */
            whereweare = vare;
 
            /* Store variable name expression to lookup (and truncate). */
            ast_copy_string(var, vars, len + 1);
 
            /* Substitute if necessary */
            if (needsub) {
                pbx_substitute_variables_helper_full_location(c, headp, var, ltmp, VAR_BUF_SIZE - 1, NULL, context, exten, pri);
                vars = ltmp;
            } else {
                vars = var;
            }
 
            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;
 
                    bogus = ast_dummy_channel_alloc();
                    if (bogus) {
                        old = *ast_channel_varshead(bogus);
                        *ast_channel_varshead(bogus) = *headp;
                        cp4 = ast_func_read(bogus, vars, workspace, VAR_BUF_SIZE) ? NULL : workspace;
                        /* Don't deallocate the varshead that was passed in */
                        *ast_channel_varshead(bogus) = old;
                        ast_channel_unref(bogus);
                    } else {
                        ast_log(LOG_ERROR, "Unable to allocate bogus channel for function value substitution.\n");
                        cp4 = NULL;
                    }
                }
                ast_debug(2, "Function %s result is '%s'\n", vars, cp4 ? cp4 : "(null)");
            } else {
                /* Retrieve variable value */
                /* For dialplan location, if we were told what to substitute explicitly, use that instead */
                if (exten && !strcmp(vars, "EXTEN")) {
                    ast_copy_string(workspace, exten, VAR_BUF_SIZE);
                    cp4 = workspace;
                } else if (context && !strcmp(vars, "CONTEXT")) {
                    ast_copy_string(workspace, context, VAR_BUF_SIZE);
                    cp4 = workspace;
                } else if (pri && !strcmp(vars, "PRIORITY")) {
                    snprintf(workspace, VAR_BUF_SIZE, "%d", pri);
                    cp4 = workspace;
                } else {
                    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++;
            }
            len = vare - vars;
            if (brackets) {
                ast_log(LOG_WARNING, "Error in extension logic (missing ']')\n");
            } else {
                /* Don't count the closing ']' in the length. */
                --len;
            }
 
            /* Skip totally over expression */
            whereweare = vare;
 
            /* Store expression to evaluate (and truncate). */
            ast_copy_string(var, vars, len + 1);
 
            /* Substitute if necessary */
            if (needsub) {
                pbx_substitute_variables_helper_full_location(c, headp, var, ltmp, VAR_BUF_SIZE - 1, NULL, context, exten, pri);
                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;
            }
        }
    }
    if (used) {
        *used = cp2 - orig_cp2;
    }
    (*recurse_depth)--;
}

References ast_channel_unref, ast_channel_varshead(), ast_copy_string(), ast_debug, ast_dummy_channel_alloc, ast_expr(), ast_func_read(), ast_log, ast_strlen_zero(), ast_threadstorage_get(), c, voicemailpwcheck::context, ast_channel::exten, len(), LOG_ERROR, LOG_WARNING, MAX_VARIABLE_SUB_RECURSE_DEPTH, NULL, parse_variable_name(), pbx_retrieve_variable(), pbx_substitute_variables_helper_full_location(), substring(), var, VAR_BUF_SIZE, and varsub_recurse_level.

Referenced by eval_exten_read(), pbx_substitute_variables_helper_full(), and pbx_substitute_variables_helper_full_location().

pbx_substitute_variables_varshead()

void pbx_substitute_variables_varshead	(	struct varshead *	headp,
		const char *	cp1,
		char *	cp2,
		int	count
	)

Definition at line 918 of file pbx_variables.c.

{
    pbx_substitute_variables_helper_full(NULL, headp, cp1, cp2, count, NULL);
}

References NULL, and pbx_substitute_variables_helper_full().

Referenced by do_say(), dundi_lookup_local(), get_mapping_weight(), and loopback_subst().

substring()

static char * substring ( const char *  value, int  offset, int  length, char *  workspace, size_t  workspace_len  )

static

takes a substring. It is ok to call with value == workspace.

Parameters

value
offset	< 0 means start from the end of the string and set the beginning to be that many characters back.
length	is the length of the substring, a value less than 0 means to leave that many off the end.
workspace
workspace_len	Always return a copy in workspace.

Definition at line 158 of file pbx_variables.c.

{
    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;
}

References ast_copy_string(), and value.

Referenced by pbx_substitute_variables_helper_full_location().

unload_pbx_variables()

static void unload_pbx_variables ( void  )

static

Definition at line 1439 of file pbx_variables.c.

{
    ast_cli_unregister_multiple(vars_cli, ARRAY_LEN(vars_cli));
    ast_unregister_application("Set");
    ast_unregister_application("MSet");
    pbx_builtin_clear_globals();
    AST_TEST_UNREGISTER(test_variable_substrings);
}

References ARRAY_LEN, ast_cli_unregister_multiple(), AST_TEST_UNREGISTER, ast_unregister_application(), pbx_builtin_clear_globals(), and vars_cli.

Referenced by load_pbx_variables().

Variable Documentation

cli_chan

int cli_chan = 0

static

Definition at line 991 of file pbx_variables.c.

Referenced by handle_eval_function().

globals

struct varshead globals = AST_LIST_HEAD_NOLOCK_INIT_VALUE

static

Definition at line 118 of file pbx_variables.c.

Referenced by ast_str_retrieve_variable(), handle_show_globals(), pbx_builtin_clear_globals(), pbx_builtin_getvar_helper(), pbx_builtin_pushvar_helper(), and pbx_builtin_setvar_helper().

globalslock

ast_rwlock_t globalslock = { PTHREAD_RWLOCK_INITIALIZER , NULL, {1, 0} }

static

Definition at line 117 of file pbx_variables.c.

Referenced by ast_str_retrieve_variable(), handle_show_globals(), pbx_builtin_clear_globals(), pbx_builtin_getvar_helper(), pbx_builtin_pushvar_helper(), and pbx_builtin_setvar_helper().

mock_channel_tech

const struct ast_channel_tech mock_channel_tech

static

Initial value:

= {
}

Definition at line 988 of file pbx_variables.c.

Referenced by handle_eval_function().

vars_cli

struct ast_cli_entry vars_cli[]

static

Definition at line 1431 of file pbx_variables.c.

Referenced by load_pbx_variables(), and unload_pbx_variables().

varsub_recurse_level

struct ast_threadstorage varsub_recurse_level = { .once = PTHREAD_ONCE_INIT , .key_init = __init_varsub_recurse_level , .custom_init = NULL , }

static

Definition at line 673 of file pbx_variables.c.

Referenced by pbx_substitute_variables_helper_full_location().