asterisk/apps/app_nbscat.c

/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2005, Digium, Inc.
 *
 * Mark Spencer <markster@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 Silly application to play an NBScat file -- uses nbscat8k
 *
 * \author Mark Spencer <markster@digium.com>
 *  
 * \ingroup applications
 */
 
/*** MODULEINFO
	<depend>working_fork</depend>
 ***/

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision$")

#include <fcntl.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <signal.h>
#ifdef HAVE_CAP
#include <sys/capability.h>
#endif /* HAVE_CAP */

#include "asterisk/lock.h"
#include "asterisk/file.h"
#include "asterisk/channel.h"
#include "asterisk/frame.h"
#include "asterisk/pbx.h"
#include "asterisk/module.h"
#include "asterisk/translate.h"

#define LOCAL_NBSCAT "/usr/local/bin/nbscat8k"
#define NBSCAT "/usr/bin/nbscat8k"

#ifndef AF_LOCAL
#define AF_LOCAL AF_UNIX
#endif

static char *app = "NBScat";

static char *synopsis = "Play an NBS local stream";

static char *descrip = 
"  NBScat(): Executes nbscat to listen to the local NBS stream.\n"
"User can exit by pressing any key.\n";


static int NBScatplay(int fd)
{
	int res;
	int x;
	sigset_t fullset, oldset;
#ifdef HAVE_CAP
	cap_t cap;
#endif

	sigfillset(&fullset);
	pthread_sigmask(SIG_BLOCK, &fullset, &oldset);

	res = fork();
	if (res < 0) 
		ast_log(LOG_WARNING, "Fork failed\n");
	if (res) {
		pthread_sigmask(SIG_SETMASK, &oldset, NULL);
		return res;
	}
	signal(SIGPIPE, SIG_DFL);
	pthread_sigmask(SIG_UNBLOCK, &fullset, NULL);

#ifdef HAVE_CAP
	cap = cap_from_text("cap_net_admin-eip");

	if (cap_set_proc(cap)) {
		/* Careful with order! Logging cannot happen after we close FDs */
		ast_log(LOG_WARNING, "Unable to remove capabilities.\n");
	}
	cap_free(cap);
#endif
	if (ast_opt_high_priority)
		ast_set_priority(0);

	dup2(fd, STDOUT_FILENO);
	for (x = STDERR_FILENO + 1; x < 1024; x++) {
		if (x != STDOUT_FILENO)
			close(x);
	}
	/* Most commonly installed in /usr/local/bin */
	execl(NBSCAT, "nbscat8k", "-d", (char *)NULL);
	execl(LOCAL_NBSCAT, "nbscat8k", "-d", (char *)NULL);
	ast_log(LOG_WARNING, "Execute of nbscat8k failed\n");
	_exit(0);
}

static int timed_read(int fd, void *data, int datalen)
{
	int res;
	struct pollfd fds[1];
	fds[0].fd = fd;
	fds[0].events = POLLIN;
	res = ast_poll(fds, 1, 2000);
	if (res < 1) {
		ast_log(LOG_NOTICE, "Selected timed out/errored out with %d\n", res);
		return -1;
	}
	return read(fd, data, datalen);
	
}

static int NBScat_exec(struct ast_channel *chan, void *data)
{
	int res=0;
	int fds[2];
	int ms = -1;
	int pid = -1;
	int owriteformat;
	struct timeval next;
	struct ast_frame *f;
	struct myframe {
		struct ast_frame f;
		char offset[AST_FRIENDLY_OFFSET];
		short frdata[160];
	} myf;
	
	if (socketpair(AF_LOCAL, SOCK_STREAM, 0, fds)) {
		ast_log(LOG_WARNING, "Unable to create socketpair\n");
		return -1;
	}
	
	ast_stopstream(chan);

	owriteformat = chan->writeformat;
	res = ast_set_write_format(chan, AST_FORMAT_SLINEAR);
	if (res < 0) {
		ast_log(LOG_WARNING, "Unable to set write format to signed linear\n");
		return -1;
	}
	
	res = NBScatplay(fds[1]);
	/* Wait 1000 ms first */
	next = ast_tvnow();
	next.tv_sec += 1;
	if (res >= 0) {
		pid = res;
		/* Order is important -- there's almost always going to be mp3...  we want to prioritize the
		   user */
		for (;;) {
			ms = ast_tvdiff_ms(next, ast_tvnow());
			if (ms <= 0) {
				res = timed_read(fds[0], myf.frdata, sizeof(myf.frdata));
				if (res > 0) {
					myf.f.frametype = AST_FRAME_VOICE;
					myf.f.subclass = AST_FORMAT_SLINEAR;
					myf.f.datalen = res;
					myf.f.samples = res / 2;
					myf.f.mallocd = 0;
					myf.f.offset = AST_FRIENDLY_OFFSET;
					myf.f.src = __PRETTY_FUNCTION__;
					myf.f.delivery.tv_sec = 0;
					myf.f.delivery.tv_usec = 0;
					myf.f.data = myf.frdata;
					if (ast_write(chan, &myf.f) < 0) {
						res = -1;
						break;
					}
				} else {
					ast_debug(1, "No more mp3\n");
					res = 0;
					break;
				}
				next = ast_tvadd(next, ast_samp2tv(myf.f.samples, 8000));
			} else {
				ms = ast_waitfor(chan, ms);
				if (ms < 0) {
					ast_debug(1, "Hangup detected\n");
					res = -1;
					break;
				}
				if (ms) {
					f = ast_read(chan);
					if (!f) {
						ast_debug(1, "Null frame == hangup() detected\n");
						res = -1;
						break;
					}
					if (f->frametype == AST_FRAME_DTMF) {
						ast_debug(1, "User pressed a key\n");
						ast_frfree(f);
						res = 0;
						break;
					}
					ast_frfree(f);
				} 
			}
		}
	}
	close(fds[0]);
	close(fds[1]);
	
	if (pid > -1)
		kill(pid, SIGKILL);
	if (!res && owriteformat)
		ast_set_write_format(chan, owriteformat);

	return res;
}

static int unload_module(void)
{
	return ast_unregister_application(app);
}

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

AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Silly NBS Stream Application");