Asterisk.org: Developer Documentation (28 Oct 2009)

Wed Oct 28 15:47:48 2009

## Asterisk developer's documentation

# app_mp3.c

Go to the documentation of this file.

    00001 /*
    00002  * Asterisk -- An open source telephony toolkit.
    00003  *
    00004  * Copyright (C) 1999 - 2005, Digium, Inc.
    00005  *
    00006  * Mark Spencer <markster@digium.com>
    00007  *
    00008  * See http://www.asterisk.org for more information about
    00009  * the Asterisk project. Please do not directly contact
    00010  * any of the maintainers of this project for assistance;
    00011  * the project provides a web site, mailing lists and IRC
    00012  * channels for your use.
    00013  *
    00014  * This program is free software, distributed under the terms of
    00015  * the GNU General Public License Version 2. See the LICENSE file
    00016  * at the top of the source tree.
    00017  */
    00018
    00019 /*! \file
    00020  *
    00021  * \brief Silly application to play an MP3 file -- uses mpg123
    00022  *
    00023  * \ingroup applications
    00024  */
    00025
    00026 #include <string.h>
    00027 #include <stdio.h>
    00028 #include <signal.h>
    00029 #include <stdlib.h>
    00030 #include <unistd.h>
    00031 #include <fcntl.h>
    00032 #include <sys/time.h>
    00033
    00034 #include "asterisk.h"
    00035
    00036 ASTERISK_FILE_VERSION(__FILE__, "$Revision: 48374 $")
    00037
    00038 #include "asterisk/lock.h"
    00039 #include "asterisk/file.h"
    00040 #include "asterisk/logger.h"
    00041 #include "asterisk/channel.h"
    00042 #include "asterisk/frame.h"
    00043 #include "asterisk/pbx.h"
    00044 #include "asterisk/module.h"
    00045 #include "asterisk/translate.h"
    00046 #include "asterisk/options.h"
    00047
    00048 #define LOCAL_MPG_123 "/usr/local/bin/mpg123"
    00049 #define MPG_123 "/usr/bin/mpg123"
    00050
    00051 static char *tdesc = "Silly MP3 Application";
    00052
    00053 static char *app = "MP3Player";
    00054
    00055 static char *synopsis = "Play an MP3 file or stream";
    00056
    00057 static char *descrip =
    00058 "  MP3Player(location) Executes mpg123 to play the given location,\n"
    00059 "which typically would be a filename or a URL. User can exit by pressing\n"
    00060 "any key on the dialpad, or by hanging up.";
    00061
    00062 STANDARD_LOCAL_USER;
    00063
    00064 LOCAL_USER_DECL;
    00065
    00066 static int mp3play(char *filename, int fd)
    00067 {
    00068    int res;
    00069    int x;
    00070    sigset_t fullset, oldset;
    00071
    00072    sigfillset(&fullset);
    00073    pthread_sigmask(SIG_BLOCK, &fullset, &oldset);
    00074
    00075    res = fork();
    00076    if (res < 0)
    00077       ast_log(LOG_WARNING, "Fork failed\n");
    00078    if (res) {
    00079       pthread_sigmask(SIG_SETMASK, &oldset, NULL);
    00080       return res;
    00081    }
    00082    if (option_highpriority)
    00083       ast_set_priority(0);
    00084    signal(SIGPIPE, SIG_DFL);
    00085    pthread_sigmask(SIG_UNBLOCK, &fullset, NULL);
    00086
    00087    dup2(fd, STDOUT_FILENO);
    00088    for (x=STDERR_FILENO + 1;x<256;x++) {
    00089       if (x != STDOUT_FILENO)
    00090          close(x);
    00091    }
    00092    /* Execute mpg123, but buffer if it's a net connection */
    00093    if (!strncasecmp(filename, "http://", 7)) {
    00094       /* Most commonly installed in /usr/local/bin */
    00095        execl(LOCAL_MPG_123, "mpg123", "-q", "-s", "-b", "1024", "-f", "8192", "--mono", "-r", "8000", filename, (char *)NULL);
    00096       /* But many places has it in /usr/bin */
    00097        execl(MPG_123, "mpg123", "-q", "-s", "-b", "1024","-f", "8192", "--mono", "-r", "8000", filename, (char *)NULL);
    00098       /* As a last-ditch effort, try to use PATH */
    00099        execlp("mpg123", "mpg123", "-q", "-s", "-b", "1024",  "-f", "8192", "--mono", "-r", "8000", filename, (char *)NULL);
    00100    }
    00101    else {
    00102       /* Most commonly installed in /usr/local/bin */
    00103        execl(MPG_123, "mpg123", "-q", "-s", "-f", "8192", "--mono", "-r", "8000", filename, (char *)NULL);
    00104       /* But many places has it in /usr/bin */
    00105        execl(LOCAL_MPG_123, "mpg123", "-q", "-s", "-f", "8192", "--mono", "-r", "8000", filename, (char *)NULL);
    00106       /* As a last-ditch effort, try to use PATH */
    00107        execlp("mpg123", "mpg123", "-q", "-s", "-f", "8192", "--mono", "-r", "8000", filename, (char *)NULL);
    00108    }
    00109    ast_log(LOG_WARNING, "Execute of mpg123 failed\n");
    00110    _exit(0);
    00111 }
    00112
    00113 static int timed_read(int fd, void *data, int datalen, int timeout)
    00114 {
    00115    int res;
    00116    struct pollfd fds[1];
    00117    fds[0].fd = fd;
    00118    fds[0].events = POLLIN;
    00119    res = poll(fds, 1, timeout);
    00120    if (res < 1) {
    00121       ast_log(LOG_NOTICE, "Poll timed out/errored out with %d\n", res);
    00122       return -1;
    00123    }
    00124    return read(fd, data, datalen);
    00125
    00126 }
    00127
    00128 static int mp3_exec(struct ast_channel *chan, void *data)
    00129 {
    00130    int res=0;
    00131    struct localuser *u;
    00132    int fds[2];
    00133    int ms = -1;
    00134    int pid = -1;
    00135    int owriteformat;
    00136    int timeout = 2000;
    00137    struct timeval next;
    00138    struct ast_frame *f;
    00139    struct myframe {
    00140       struct ast_frame f;
    00141       char offset[AST_FRIENDLY_OFFSET];
    00142       short frdata[160];
    00143    } myf;
    00144
    00145    if (ast_strlen_zero(data)) {
    00146       ast_log(LOG_WARNING, "MP3 Playback requires an argument (filename)\n");
    00147       return -1;
    00148    }
    00149
    00150    LOCAL_USER_ADD(u);
    00151
    00152    if (pipe(fds)) {
    00153       ast_log(LOG_WARNING, "Unable to create pipe\n");
    00154       LOCAL_USER_REMOVE(u);
    00155       return -1;
    00156    }
    00157
    00158    ast_stopstream(chan);
    00159
    00160    owriteformat = chan->writeformat;
    00161    res = ast_set_write_format(chan, AST_FORMAT_SLINEAR);
    00162    if (res < 0) {
    00163       ast_log(LOG_WARNING, "Unable to set write format to signed linear\n");
    00164       LOCAL_USER_REMOVE(u);
    00165       return -1;
    00166    }
    00167
    00168    res = mp3play((char *)data, fds[1]);
    00169    if (!strncasecmp((char *)data, "http://", 7)) {
    00170       timeout = 10000;
    00171    }
    00172    /* Wait 1000 ms first */
    00173    next = ast_tvnow();
    00174    next.tv_sec += 1;
    00175    if (res >= 0) {
    00176       pid = res;
    00177       /* Order is important -- there's almost always going to be mp3...  we want to prioritize the
    00178          user */
    00179       for (;;) {
    00180          ms = ast_tvdiff_ms(next, ast_tvnow());
    00181          if (ms <= 0) {
    00182             res = timed_read(fds[0], myf.frdata, sizeof(myf.frdata), timeout);
    00183             if (res > 0) {
    00184                myf.f.frametype = AST_FRAME_VOICE;
    00185                myf.f.subclass = AST_FORMAT_SLINEAR;
    00186                myf.f.datalen = res;
    00187                myf.f.samples = res / 2;
    00188                myf.f.mallocd = 0;
    00189                myf.f.offset = AST_FRIENDLY_OFFSET;
    00190                myf.f.src = __PRETTY_FUNCTION__;
    00191                myf.f.delivery.tv_sec = 0;
    00192                myf.f.delivery.tv_usec = 0;
    00193                myf.f.data = myf.frdata;
    00194                if (ast_write(chan, &myf.f) < 0) {
    00195                   res = -1;
    00196                   break;
    00197                }
    00198             } else {
    00199                ast_log(LOG_DEBUG, "No more mp3\n");
    00200                res = 0;
    00201                break;
    00202             }
    00203             next = ast_tvadd(next, ast_samp2tv(myf.f.samples, 8000));
    00204          } else {
    00205             ms = ast_waitfor(chan, ms);
    00206             if (ms < 0) {
    00207                ast_log(LOG_DEBUG, "Hangup detected\n");
    00208                res = -1;
    00209                break;
    00210             }
    00211             if (ms) {
    00212                f = ast_read(chan);
    00213                if (!f) {
    00214                   ast_log(LOG_DEBUG, "Null frame == hangup() detected\n");
    00215                   res = -1;
    00216                   break;
    00217                }
    00218                if (f->frametype == AST_FRAME_DTMF) {
    00219                   ast_log(LOG_DEBUG, "User pressed a key\n");
    00220                   ast_frfree(f);
    00221                   res = 0;
    00222                   break;
    00223                }
    00224                ast_frfree(f);
    00225             }
    00226          }
    00227       }
    00228    }
    00229    close(fds[0]);
    00230    close(fds[1]);
    00231
    00232    if (pid > -1)
    00233       kill(pid, SIGKILL);
    00234    if (!res && owriteformat)
    00235       ast_set_write_format(chan, owriteformat);
    00236
    00237    LOCAL_USER_REMOVE(u);
    00238
    00239    return res;
    00240 }
    00241
    00242 int unload_module(void)
    00243 {
    00244    int res;
    00245
    00246    res = ast_unregister_application(app);
    00247
    00248    STANDARD_HANGUP_LOCALUSERS;
    00249
    00250    return res;
    00251 }
    00252
    00253 int load_module(void)
    00254 {
    00255    return ast_register_application(app, mp3_exec, synopsis, descrip);
    00256 }
    00257
    00258 char *description(void)
    00259 {
    00260    return tdesc;
    00261 }
    00262
    00263 int usecount(void)
    00264 {
    00265    int res;
    00266    STANDARD_USECOUNT(res);
    00267    return res;
    00268 }
    00269
    00270 char *key()
    00271 {
    00272    return ASTERISK_GPL_KEY;
    00273 }