DIALPLAN EXISTS

/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2007, Digium, Inc.
 *
 * 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 Dialplan group functions check if a context exists
 *
 * \author Gregory Nietsky AKA irroot <gregory@networksentry.co.za>
 * \author Russell Bryant <russell@digium.com>
 *
 * \ingroup functions
 */

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision$")

#include "asterisk/module.h"
#include "asterisk/channel.h"
#include "asterisk/pbx.h"
#include "asterisk/app.h"

static int isexten_function_read(struct ast_channel *chan, const char *cmd, char *data,
        char *buf, size_t len)
{
        char *parse;
        AST_DECLARE_APP_ARGS(args,
                AST_APP_ARG(context);
                AST_APP_ARG(exten);
                AST_APP_ARG(priority);
        );

        strcpy(buf, "0");

        if (ast_strlen_zero(data)) {
                ast_log(LOG_ERROR, "DIALPLAN_EXISTS() requires an argument\n");
                return -1;
        }

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

        if (!ast_strlen_zero(args.priority)) {
                int priority_num;
                if (sscanf(args.priority, "%d", &priority_num) == 1 && priority_num > 0) {
                        int res;
                        res = ast_exists_extension(chan, args.context, args.exten, priority_num,
                                chan->cid.cid_num);
                        if (res)
                                strcpy(buf, "1");
                } else {
                        int res;
                        res = ast_findlabel_extension(chan, args.context, args.exten,
                                args.priority, chan->cid.cid_num);
                        if (res > 0)
                                strcpy(buf, "1");
                }
        } else if (!ast_strlen_zero(args.exten)) {
                int res;
                res = ast_exists_extension(chan, args.context, args.exten, 1,
                        chan->cid.cid_num);
                if (res)
                        strcpy(buf, "1");
        } else if (!ast_strlen_zero(args.context)) {
                if (ast_context_find(args.context))
                        strcpy(buf, "1");
        } else {
                ast_log(LOG_ERROR, "Invalid arguments provided to DIALPLAN_EXISTS\n");
                return -1;
        }

        return 0;
}

static struct ast_custom_function isexten_function = {
        .name = "DIALPLAN_EXISTS",
        .syntax = "DIALPLAN_EXISTS(context[,extension[,priority]])",
        .synopsis = "Checks the existence of a dialplan target.",
        .desc = "This function returns 1 if the target exits.  Otherwise, it returns 0.\n",
        .read = isexten_function_read,
};

static int unload_module(void)
{
        return ast_custom_function_unregister(&isexten_function);
}

static int load_module(void)
{
        return ast_custom_function_register(&isexten_function);
}

AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Dialplan Context/Extension/Priority Checking Functions");