app_directed_pickup.c

/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2005, Joshua Colp
 *
 * Joshua Colp <jcolp@digium.com>
 *
 * 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 Directed Call Pickup Support
 *
 * \author Joshua Colp <jcolp@digium.com>
 *
 * \ingroup applications
 */

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision$")

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>

#include "asterisk/file.h"
#include "asterisk/logger.h"
#include "asterisk/channel.h"
#include "asterisk/pbx.h"
#include "asterisk/module.h"
#include "asterisk/lock.h"
#include "asterisk/app.h"
#include "asterisk/options.h"

#define PICKUPMARK "PICKUPMARK"

static const char *app = "Pickup";
static const char *synopsis = "Directed Call Pickup";
static const char *descrip =
"  Pickup(extension[@context][&extension2@context...]): This application can pickup any ringing channel\n"
"that is calling the specified extension. If no context is specified, the current\n"
"context will be used. If you use the special string \"PICKUPMARK\" for the context parameter, for example\n"
"10@PICKUPMARK, this application tries to find a channel which has defined a channel variable with the same context\n"
"as \"extension\".";


static int pickup_exec(struct ast_channel *chan, void *data)
{
	int res = 0;
	struct ast_module_user *u = NULL;
	struct ast_channel *origin = NULL, *target = NULL;
	char *tmp = NULL, *exten = NULL, *context = NULL, *rest=data;
	char workspace[256] = "";
	const char *tmp2 = NULL;

	if (ast_strlen_zero(data)) {
		ast_log(LOG_WARNING, "Pickup requires an argument (extension) !\n");
		return -1;	
	}

	u = ast_module_user_add(chan);
	
	while (!target && (exten = rest) ) {
		res = 0;
		rest = strchr(exten, '&');
		if (rest)
			*rest++ = 0;

		/* Get the extension and context if present */
		context = strchr(exten, '@');
		if (context)
			*context++ = '\0';

		/* If the context is the pickup mark, iterate through all channels finding the right origin one */
		if (context && !strcmp(context, PICKUPMARK)) {
			while ((origin = ast_channel_walk_locked(origin))) {
				if (origin) {
					tmp2 = pbx_builtin_getvar_helper(origin, PICKUPMARK);
					if (tmp2 && !strcmp(tmp2, exten))
						break;
					ast_mutex_unlock(&origin->lock);
				}
			}
		} else {
			/* Use the classic mode of searching */
			origin = ast_get_channel_by_exten_locked(exten, context);
		}

		if (origin) {
			ast_cdr_getvar(origin->cdr, "dstchannel", &tmp, workspace,
					sizeof(workspace), 0, 0);
			if (tmp) {
				/* We have a possible channel... now we need to find it! */
				target = ast_get_channel_by_name_locked(tmp);
			} else {
				ast_log(LOG_NOTICE, "No target channel found for %s.\n", exten);
				res = -1;
			}
			ast_mutex_unlock(&origin->lock);

		} else {
			if (option_debug)
				ast_log(LOG_DEBUG, "No originating channel found.\n");
		}

		if (res)
			continue;

		if (target && (!target->pbx) && ((target->_state == AST_STATE_RINGING) || (target->_state == AST_STATE_RING) ) ) {
			if (option_debug)
				ast_log(LOG_DEBUG, "Call pickup on chan '%s' by '%s'\n", target->name,
					chan->name);
			res = ast_answer(chan);
			if (res) {
				ast_log(LOG_WARNING, "Unable to answer '%s'\n", chan->name);
				res = -1;
				break;
			}
			res = ast_queue_control(chan, AST_CONTROL_ANSWER);
			if (res) {
				ast_log(LOG_WARNING, "Unable to queue answer on '%s'\n",
						chan->name);
				res = -1;
				break;
			}
			res = ast_channel_masquerade(target, chan);
			if (res) {
				ast_log(LOG_WARNING, "Unable to masquerade '%s' into '%s'\n", chan->name, target->name);
				res = -1;
				break;
			}
		} else {
			ast_log(LOG_NOTICE, "No call pickup possible for %s...\n", exten);
			res = -1;
		}
	}
	if (target) 
		ast_mutex_unlock(&target->lock);
	
	ast_module_user_remove(u);

	return res;
}

static int unload_module(void)
{
	int res;

	res = ast_unregister_application(app);
	
	return res;
}

static int load_module(void)
{
	return ast_register_application(app, pickup_exec, synopsis, descrip);
}

AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Directed Call Pickup Application");