apps/app_echo.c

   1 /*
   2  * Asterisk -- An open source telephony toolkit.
   3  *
   4  * Copyright (C) 1999 - 2005, Digium, Inc.
   5  *
   6  * Mark Spencer <markster@digium.com>
   7  *
   8  * See http://www.asterisk.org for more information about
   9  * the Asterisk project. Please do not directly contact
  10  * any of the maintainers of this project for assistance;
  11  * the project provides a web site, mailing lists and IRC
  12  * channels for your use.
  13  *
  14  * This program is free software, distributed under the terms of
  15  * the GNU General Public License Version 2. See the LICENSE file
  16  * at the top of the source tree.
  17  */
  18
  19 /*! \file
  20  *
  21  * \brief Echo application -- play back what you hear to evaluate latency
  22  *
  23  * \author Mark Spencer <markster@digium.com>
  24  *
  25  * \ingroup applications
  26  */
  27
  28 #include "asterisk.h"
  29
  30 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
  31
  32 #include "asterisk/file.h"
  33 #include "asterisk/module.h"
  34 #include "asterisk/channel.h"
  35
  36 static char *app = "Echo";
  37
  38 static char *synopsis = "Echo audio, video, or DTMF back to the calling party";
  39
  40 static char *descrip =
  41 "  Echo(): This application will echo any audio, video, or DTMF frames read from\n"
  42 "the calling channel back to itself. If the DTMF digit '#' is received, the\n"
  43 "application will exit.\n";
  44
  45
  46 static int echo_exec(struct ast_channel *chan, void *data)
  47 {
  48         int res = -1;
  49         int format;
  50
  51         format = ast_best_codec(chan->nativeformats);
  52         ast_set_write_format(chan, format);
  53         ast_set_read_format(chan, format);
  54
  55         while (ast_waitfor(chan, -1) > -1) {
  56                 struct ast_frame *f = ast_read(chan);
  57                 if (!f)
  58                         break;
  59                 f->delivery.tv_sec = 0;
  60                 f->delivery.tv_usec = 0;
  61                 if (ast_write(chan, f)) {
  62                         ast_frfree(f);
  63                         goto end;
  64                 }
  65                 if ((f->frametype == AST_FRAME_DTMF) && (f->subclass == '#')) {
  66                         res = 0;
  67                         ast_frfree(f);
  68                         goto end;
  69                 }
  70                 ast_frfree(f);
  71         }
  72 end:
  73         return res;
  74 }
  75
  76 static int unload_module(void)
  77 {
  78         return ast_unregister_application(app);
  79 }
  80
  81 static int load_module(void)
  82 {
  83         return ast_register_application(app, echo_exec, synopsis, descrip);
  84 }
  85
  86 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Simple Echo Application");