Thu Jul 9 13:40:19 2009

Asterisk developer's documentation


app_nbscat.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 NBScat file -- uses nbscat8k
00022  *
00023  * \author Mark Spencer <markster@digium.com>
00024  *  
00025  * \ingroup applications
00026  */
00027  
00028 /*** MODULEINFO
00029    <depend>working_fork</depend>
00030  ***/
00031 
00032 #include "asterisk.h"
00033 
00034 ASTERISK_FILE_VERSION(__FILE__, "$Revision: 182945 $")
00035 
00036 #include <fcntl.h>
00037 #include <sys/time.h>
00038 #include <sys/socket.h>
00039 #include <signal.h>
00040 #ifdef HAVE_CAP
00041 #include <sys/capability.h>
00042 #endif /* HAVE_CAP */
00043 
00044 #include "asterisk/lock.h"
00045 #include "asterisk/file.h"
00046 #include "asterisk/channel.h"
00047 #include "asterisk/frame.h"
00048 #include "asterisk/pbx.h"
00049 #include "asterisk/module.h"
00050 #include "asterisk/translate.h"
00051 
00052 #define LOCAL_NBSCAT "/usr/local/bin/nbscat8k"
00053 #define NBSCAT "/usr/bin/nbscat8k"
00054 
00055 #ifndef AF_LOCAL
00056 #define AF_LOCAL AF_UNIX
00057 #endif
00058 
00059 static char *app = "NBScat";
00060 
00061 static char *synopsis = "Play an NBS local stream";
00062 
00063 static char *descrip = 
00064 "  NBScat(): Executes nbscat to listen to the local NBS stream.\n"
00065 "User can exit by pressing any key.\n";
00066 
00067 
00068 static int NBScatplay(int fd)
00069 {
00070    int res;
00071    int x;
00072    sigset_t fullset, oldset;
00073 #ifdef HAVE_CAP
00074    cap_t cap;
00075 #endif
00076 
00077    sigfillset(&fullset);
00078    pthread_sigmask(SIG_BLOCK, &fullset, &oldset);
00079 
00080    res = fork();
00081    if (res < 0) 
00082       ast_log(LOG_WARNING, "Fork failed\n");
00083    if (res) {
00084       pthread_sigmask(SIG_SETMASK, &oldset, NULL);
00085       return res;
00086    }
00087    signal(SIGPIPE, SIG_DFL);
00088    pthread_sigmask(SIG_UNBLOCK, &fullset, NULL);
00089 
00090 #ifdef HAVE_CAP
00091    cap = cap_from_text("cap_net_admin-eip");
00092 
00093    if (cap_set_proc(cap)) {
00094       /* Careful with order! Logging cannot happen after we close FDs */
00095       ast_log(LOG_WARNING, "Unable to remove capabilities.\n");
00096    }
00097    cap_free(cap);
00098 #endif
00099    if (ast_opt_high_priority)
00100       ast_set_priority(0);
00101 
00102    dup2(fd, STDOUT_FILENO);
00103    for (x = STDERR_FILENO + 1; x < 1024; x++) {
00104       if (x != STDOUT_FILENO)
00105          close(x);
00106    }
00107    /* Most commonly installed in /usr/local/bin */
00108    execl(NBSCAT, "nbscat8k", "-d", (char *)NULL);
00109    execl(LOCAL_NBSCAT, "nbscat8k", "-d", (char *)NULL);
00110    ast_log(LOG_WARNING, "Execute of nbscat8k failed\n");
00111    _exit(0);
00112 }
00113 
00114 static int timed_read(int fd, void *data, int datalen)
00115 {
00116    int res;
00117    struct pollfd fds[1];
00118    fds[0].fd = fd;
00119    fds[0].events = POLLIN;
00120    res = ast_poll(fds, 1, 2000);
00121    if (res < 1) {
00122       ast_log(LOG_NOTICE, "Selected timed out/errored out with %d\n", res);
00123       return -1;
00124    }
00125    return read(fd, data, datalen);
00126    
00127 }
00128 
00129 static int NBScat_exec(struct ast_channel *chan, void *data)
00130 {
00131    int res=0;
00132    int fds[2];
00133    int ms = -1;
00134    int pid = -1;
00135    int owriteformat;
00136    struct timeval next;
00137    struct ast_frame *f;
00138    struct myframe {
00139       struct ast_frame f;
00140       char offset[AST_FRIENDLY_OFFSET];
00141       short frdata[160];
00142    } myf;
00143    
00144    if (socketpair(AF_LOCAL, SOCK_STREAM, 0, fds)) {
00145       ast_log(LOG_WARNING, "Unable to create socketpair\n");
00146       return -1;
00147    }
00148    
00149    ast_stopstream(chan);
00150 
00151    owriteformat = chan->writeformat;
00152    res = ast_set_write_format(chan, AST_FORMAT_SLINEAR);
00153    if (res < 0) {
00154       ast_log(LOG_WARNING, "Unable to set write format to signed linear\n");
00155       return -1;
00156    }
00157    
00158    res = NBScatplay(fds[1]);
00159    /* Wait 1000 ms first */
00160    next = ast_tvnow();
00161    next.tv_sec += 1;
00162    if (res >= 0) {
00163       pid = res;
00164       /* Order is important -- there's almost always going to be mp3...  we want to prioritize the
00165          user */
00166       for (;;) {
00167          ms = ast_tvdiff_ms(next, ast_tvnow());
00168          if (ms <= 0) {
00169             res = timed_read(fds[0], myf.frdata, sizeof(myf.frdata));
00170             if (res > 0) {
00171                myf.f.frametype = AST_FRAME_VOICE;
00172                myf.f.subclass = AST_FORMAT_SLINEAR;
00173                myf.f.datalen = res;
00174                myf.f.samples = res / 2;
00175                myf.f.mallocd = 0;
00176                myf.f.offset = AST_FRIENDLY_OFFSET;
00177                myf.f.src = __PRETTY_FUNCTION__;
00178                myf.f.delivery.tv_sec = 0;
00179                myf.f.delivery.tv_usec = 0;
00180                myf.f.data = myf.frdata;
00181                if (ast_write(chan, &myf.f) < 0) {
00182                   res = -1;
00183                   break;
00184                }
00185             } else {
00186                ast_debug(1, "No more mp3\n");
00187                res = 0;
00188                break;
00189             }
00190             next = ast_tvadd(next, ast_samp2tv(myf.f.samples, 8000));
00191          } else {
00192             ms = ast_waitfor(chan, ms);
00193             if (ms < 0) {
00194                ast_debug(1, "Hangup detected\n");
00195                res = -1;
00196                break;
00197             }
00198             if (ms) {
00199                f = ast_read(chan);
00200                if (!f) {
00201                   ast_debug(1, "Null frame == hangup() detected\n");
00202                   res = -1;
00203                   break;
00204                }
00205                if (f->frametype == AST_FRAME_DTMF) {
00206                   ast_debug(1, "User pressed a key\n");
00207                   ast_frfree(f);
00208                   res = 0;
00209                   break;
00210                }
00211                ast_frfree(f);
00212             } 
00213          }
00214       }
00215    }
00216    close(fds[0]);
00217    close(fds[1]);
00218    
00219    if (pid > -1)
00220       kill(pid, SIGKILL);
00221    if (!res && owriteformat)
00222       ast_set_write_format(chan, owriteformat);
00223 
00224    return res;
00225 }
00226 
00227 static int unload_module(void)
00228 {
00229    return ast_unregister_application(app);
00230 }
00231 
00232 static int load_module(void)
00233 {
00234    return ast_register_application(app, NBScat_exec, synopsis, descrip);
00235 }
00236 
00237 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Silly NBS Stream Application");

Generated on Thu Jul 9 13:40:19 2009 for Asterisk - the Open Source PBX by  doxygen 1.4.7