asterisk/apps/app_chanisavail.c

230 lines
6.8 KiB
C

/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (C) 1999 - 2005, Digium, Inc.
*
* Mark Spencer <markster@digium.com>
* James Golovich <james@gnuinter.net>
*
* 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 Check if Channel is Available
*
* \author Mark Spencer <markster@digium.com>
* \author James Golovich <james@gnuinter.net>
* \ingroup applications
*/
/*** MODULEINFO
<support_level>extended</support_level>
***/
#include "asterisk.h"
#include <sys/ioctl.h>
#include "asterisk/lock.h"
#include "asterisk/file.h"
#include "asterisk/channel.h"
#include "asterisk/pbx.h"
#include "asterisk/module.h"
#include "asterisk/app.h"
#include "asterisk/devicestate.h"
static const char app[] = "ChanIsAvail";
/*** DOCUMENTATION
<application name="ChanIsAvail" language="en_US">
<synopsis>
Check channel availability
</synopsis>
<syntax>
<parameter name="Technology/Resource" required="false" argsep="&amp;">
<argument name="Technology/Resource" required="true">
<para>Specification of the device(s) to check. These must be in the format of
<literal>Technology/Resource</literal>, where <replaceable>Technology</replaceable>
represents a particular channel driver, and <replaceable>Resource</replaceable>
represents a resource available to that particular channel driver.</para>
</argument>
<argument name="Technology2/Resource2" multiple="true">
<para>Optional extra devices to check</para>
<para>If you need more than one enter them as
Technology2/Resource2&amp;Technology3/Resource3&amp;.....</para>
</argument>
</parameter>
<parameter name="options" required="false">
<optionlist>
<option name="a">
<para>Check for all available channels, not only the first one</para>
</option>
<option name="s">
<para>Consider the channel unavailable if the channel is in use at all</para>
</option>
<option name="t" implies="s">
<para>Simply checks if specified channels exist in the channel list</para>
</option>
</optionlist>
</parameter>
</syntax>
<description>
<para>This application will check to see if any of the specified channels are available.</para>
<para>This application sets the following channel variables:</para>
<variablelist>
<variable name="AVAILCHAN">
<para>The name of the available channel, if one exists</para>
</variable>
<variable name="AVAILORIGCHAN">
<para>The canonical channel name that was used to create the channel</para>
</variable>
<variable name="AVAILSTATUS">
<para>The device state for the device</para>
</variable>
<variable name="AVAILCAUSECODE">
<para>The cause code returned when requesting the channel</para>
</variable>
</variablelist>
</description>
</application>
***/
static int chanavail_exec(struct ast_channel *chan, const char *data)
{
int inuse = -1;
int option_state = 0;
int string_compare = 0;
int option_all_avail = 0;
int status;
char *info;
char trychan[512];
char *rest;
char *tech;
char *number;
struct ast_str *tmp_availchan = ast_str_alloca(2048);
struct ast_str *tmp_availorig = ast_str_alloca(2048);
struct ast_str *tmp_availstat = ast_str_alloca(2048);
struct ast_str *tmp_availcause = ast_str_alloca(2048);
struct ast_channel *tempchan;
struct ast_custom_function *cdr_prop_func = ast_custom_function_find("CDR_PROP");
AST_DECLARE_APP_ARGS(args,
AST_APP_ARG(reqchans);
AST_APP_ARG(options);
);
info = ast_strdupa(data ?: "");
AST_STANDARD_APP_ARGS(args, info);
if (args.options) {
if (strchr(args.options, 'a')) {
option_all_avail = 1;
}
if (strchr(args.options, 's')) {
option_state = 1;
}
if (strchr(args.options, 't')) {
string_compare = 1;
}
}
rest = args.reqchans;
if (!rest) {
rest = "";
}
while ((tech = strsep(&rest, "&"))) {
tech = ast_strip(tech);
number = strchr(tech, '/');
if (!number) {
if (!ast_strlen_zero(tech)) {
ast_log(LOG_WARNING, "Invalid ChanIsAvail technology/resource argument: '%s'\n",
tech);
}
ast_str_append(&tmp_availstat, 0, "%s%d",
ast_str_strlen(tmp_availstat) ? "&" : "", AST_DEVICE_INVALID);
continue;
}
*number++ = '\0';
status = AST_DEVICE_UNKNOWN;
if (string_compare) {
/* ast_parse_device_state checks for "SIP/1234" as a channel name.
ast_device_state will ask the SIP driver for the channel state. */
snprintf(trychan, sizeof(trychan), "%s/%s", tech, number);
status = inuse = ast_parse_device_state(trychan);
} else if (option_state) {
/* If the pbx says in use then don't bother trying further.
This is to permit testing if someone's on a call, even if the
channel can permit more calls (ie callwaiting, sip calls, etc). */
snprintf(trychan, sizeof(trychan), "%s/%s", tech, number);
status = inuse = ast_device_state(trychan);
}
ast_str_append(&tmp_availstat, 0, "%s%d",
ast_str_strlen(tmp_availstat) ? "&" : "", status);
if ((inuse <= (int) AST_DEVICE_NOT_INUSE)
&& (tempchan = ast_request(tech, ast_channel_nativeformats(chan), NULL, chan, number, &status))) {
ast_str_append(&tmp_availchan, 0, "%s%s",
ast_str_strlen(tmp_availchan) ? "&" : "", ast_channel_name(tempchan));
ast_str_append(&tmp_availorig, 0, "%s%s/%s",
ast_str_strlen(tmp_availorig) ? "&" : "", tech, number);
ast_str_append(&tmp_availcause, 0, "%s%d",
ast_str_strlen(tmp_availcause) ? "&" : "", status);
/* Disable CDR for this temporary channel. */
if (cdr_prop_func) {
ast_func_write(tempchan, "CDR_PROP(disable)", "1");
}
ast_hangup(tempchan);
tempchan = NULL;
if (!option_all_avail) {
break;
}
}
}
pbx_builtin_setvar_helper(chan, "AVAILCHAN", ast_str_buffer(tmp_availchan));
/* Store the originally used channel too */
pbx_builtin_setvar_helper(chan, "AVAILORIGCHAN", ast_str_buffer(tmp_availorig));
pbx_builtin_setvar_helper(chan, "AVAILSTATUS", ast_str_buffer(tmp_availstat));
pbx_builtin_setvar_helper(chan, "AVAILCAUSECODE", ast_str_buffer(tmp_availcause));
return 0;
}
static int unload_module(void)
{
return ast_unregister_application(app);
}
static int load_module(void)
{
return ast_register_application_xml(app, chanavail_exec) ?
AST_MODULE_LOAD_DECLINE : AST_MODULE_LOAD_SUCCESS;
}
AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_DEFAULT, "Check channel availability",
.support_level = AST_MODULE_SUPPORT_EXTENDED,
.load = load_module,
.unload = unload_module,
.optional_modules = "func_cdr"
);