funcs/func_channel.c

   1 /*
   2  * Asterisk -- An open source telephony toolkit.
   3  *
   4  * Copyright (C) 2006, Digium, Inc.
   5  *
   6  * See http://www.asterisk.org for more information about
   7  * the Asterisk project. Please do not directly contact
   8  * any of the maintainers of this project for assistance;
   9  * the project provides a web site, mailing lists and IRC
  10  * channels for your use.
  11  *
  12  * This program is free software, distributed under the terms of
  13  * the GNU General Public License Version 2. See the LICENSE file
  14  * at the top of the source tree.
  15  */
  16
  17 /*! \file
  18  *
  19  * \brief Channel info dialplan function
  20  *
  21  * \author Kevin P. Fleming <kpfleming@digium.com>
  22  *
  23  */
  24
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <sys/types.h>
  28
  29 #include "asterisk.h"
  30
  31 ASTERISK_FILE_VERSION(__FILE__, "$Revision:  $")
  32 #include "asterisk/module.h"
  33 #include "asterisk/channel.h"
  34 #include "asterisk/pbx.h"
  35 #include "asterisk/logger.h"
  36 #include "asterisk/utils.h"
  37 #include "asterisk/app.h"
  38 #include "asterisk/indications.h"
  39 #include "asterisk/stringfields.h"
  40 #define locked_copy_string(chan, dest, source, len) \
  41         do { \
  42                 ast_mutex_lock(&chan->lock); \
  43                 ast_copy_string(dest, source, len); \
  44                 ast_mutex_unlock(&chan->lock); \
  45         } while (0)
  46 #define locked_string_field_set(chan, field, source) \
  47         do { \
  48                 ast_mutex_lock(&chan->lock); \
  49                 ast_string_field_set(chan, field, source); \
  50                 ast_mutex_unlock(&chan->lock); \
  51         } while (0)
  52
  53 static int func_channel_read(struct ast_channel *chan, char *function,
  54                              char *data, char *buf, size_t len)
  55 {
  56         int ret = 0;
  57
  58         if (!strcasecmp(data, "audionativeformat"))
  59                 /* use the _multiple version when chan->nativeformats holds multiple formats */
  60                 /* ast_getformatname_multiple(buf, len, chan->nativeformats & AST_FORMAT_AUDIO_MASK); */
  61                 ast_copy_string(buf, ast_getformatname(chan->nativeformats & AST_FORMAT_AUDIO_MASK), len);
  62         else if (!strcasecmp(data, "videonativeformat"))
  63                 /* use the _multiple version when chan->nativeformats holds multiple formats */
  64                 /* ast_getformatname_multiple(buf, len, chan->nativeformats & AST_FORMAT_VIDEO_MASK); */
  65                 ast_copy_string(buf, ast_getformatname(chan->nativeformats & AST_FORMAT_VIDEO_MASK), len);
  66         else if (!strcasecmp(data, "audioreadformat"))
  67                 ast_copy_string(buf, ast_getformatname(chan->readformat), len);
  68         else if (!strcasecmp(data, "audiowriteformat"))
  69                 ast_copy_string(buf, ast_getformatname(chan->writeformat), len);
  70         else if (!strcasecmp(data, "tonezone") && chan->zone)
  71                 locked_copy_string(chan, buf, chan->zone->country, len);
  72         else if (!strcasecmp(data, "language"))
  73                 locked_copy_string(chan, buf, chan->language, len);
  74         else if (!strcasecmp(data, "musicclass"))
  75                 locked_copy_string(chan, buf, chan->musicclass, len);
  76         else if (!chan->tech->func_channel_read
  77                  || chan->tech->func_channel_read(chan, function, data, buf, len)) {
  78                 ast_log(LOG_WARNING, "Unknown or unavailable item requested: '%s'\n", data);
  79                 ret = -1;
  80         }
  81
  82         return ret;
  83 }
  84
  85 static int func_channel_write(struct ast_channel *chan, char *function,
  86                               char *data, const char *value)
  87 {
  88         int ret = 0;
  89
  90         if (!strcasecmp(data, "language"))
  91                 locked_string_field_set(chan, language, value);
  92         else if (!strcasecmp(data, "musicclass"))
  93                 locked_string_field_set(chan, musicclass, value);
  94         else if (!chan->tech->func_channel_write
  95                  || chan->tech->func_channel_write(chan, function, data, value)) {
  96                 ast_log(LOG_WARNING, "Unknown or unavailable item requested: '%s'\n",
  97                                 data);
  98                 ret = -1;
  99         }
 100
 101         return ret;
 102 }
 103
 104 static struct ast_custom_function channel_function = {
 105         .name = "CHANNEL",
 106         .synopsis = "Gets/sets various pieces of information about the channel.",
 107         .syntax = "CHANNEL(item)",
 108         .desc = "Gets/set various pieces of information about the channel.\n"
 109                 "Standard items (provided by all channel technologies) are:\n"
 110                 "R/O    audioreadformat         format currently being read\n"
 111                 "R/O    audionativeformat       format used natively for audio\n"
 112                 "R/O    audiowriteformat        format currently being written\n"
 113                 "R/W    language                language for sounds played\n"
 114                 "R/W    musicclass              class (from musiconhold.conf) for hold music\n"
 115                 "R/O    tonezone                zone for indications played\n"
 116                 "R/O    videonativeformat       format used natively for video\n"
 117                 "\n"
 118                 "Additional items may be available from the channel driver providing\n"
 119                 "the channel; see its documentation for details.\n"
 120                 "\n"
 121                 "Any item requested that is not available on the current channel will\n"
 122                 "return an empty string.\n",
 123         .read = func_channel_read,
 124         .write = func_channel_write,
 125 };
 126
 127 static char *tdesc = "Channel information dialplan function";
 128
 129 int unload_module(void)
 130 {
 131         return ast_custom_function_unregister(&channel_function);
 132 }
 133
 134 int load_module(void)
 135 {
 136         return ast_custom_function_register(&channel_function);
 137 }
 138
 139 char *description(void)
 140 {
 141         return tdesc;
 142 }
 143
 144 int usecount(void)
 145 {
 146         return 0;
 147 }
 148
 149 char *key()
 150 {
 151         return ASTERISK_GPL_KEY;
 152 }