chanvars.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2005, Digium, Inc.
 *
 * Mark Spencer <[email protected]>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*! \file
 *
 * \brief Channel Variables
 *
 * \author Mark Spencer <[email protected]>
 */

/*** MODULEINFO
   <support_level>core</support_level>
 ***/

#include "asterisk.h"

#include "asterisk/chanvars.h"
#include "asterisk/strings.h"
#include "asterisk/utils.h"

struct ast_var_t *_ast_var_assign(const char *name, const char *value, const char *file, int lineno, const char *function)
{
   struct ast_var_t *var;
   int name_len = strlen(name) + 1;
   int value_len = strlen(value) + 1;

   var = __ast_calloc(sizeof(*var) + name_len + value_len, sizeof(char),
      file, lineno, function);
   if (!var) {
      return NULL;
   }

   ast_copy_string(var->name, name, name_len);
   var->value = var->name + name_len;
   ast_copy_string(var->value, value, value_len);

   return var;
}

void ast_var_delete(struct ast_var_t *var)
{
   ast_free(var);
}

const char *ast_var_name(const struct ast_var_t *var)
{
   const char *name;

   if (var == NULL || (name = var->name) == NULL)
      return NULL;
   /* Return the name without the initial underscores */
   if (name[0] == '_') {
      name++;
      if (name[0] == '_')
         name++;
   }
   return name;
}

const char *ast_var_full_name(const struct ast_var_t *var)
{
   return (var ? var->name : NULL);
}

const char *ast_var_value(const struct ast_var_t *var)
{
   return (var ? var->value : NULL);
}

char *ast_var_find(const struct varshead *head, const char *name)
{
   struct ast_var_t *var;

   AST_LIST_TRAVERSE(head, var, entries) {
      if (!strcmp(name, var->name)) {
         return var->value;
      }
   }
   return NULL;
}

struct varshead *ast_var_list_create(void)
{
   struct varshead *head;

   head = ast_calloc(1, sizeof(*head));
   if (!head) {
      return NULL;
   }
   AST_LIST_HEAD_INIT_NOLOCK(head);
   return head;
}

void ast_var_list_destroy(struct varshead *head)
{
   struct ast_var_t *var;

   if (!head) {
      return;
   }

   while ((var = AST_LIST_REMOVE_HEAD(head, entries))) {
      ast_var_delete(var);
   }

   ast_free(head);
}

struct varshead *ast_var_list_clone(struct varshead *head)
{
   struct varshead *clone;
   struct ast_var_t *var, *newvar;

   if (!head) {
      return NULL;
   }

   clone = ast_var_list_create();
   if (!clone) {
      return NULL;
   }

   AST_VAR_LIST_TRAVERSE(head, var) {
      newvar = ast_var_assign(var->name, var->value);
      if (!newvar) {
         ast_var_list_destroy(clone);
         return NULL;
      }
      AST_VAR_LIST_INSERT_TAIL(clone, newvar);
   }

   return clone;
}