apps/app_milliwatt.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 Digital Milliwatt Test
  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 <stdlib.h>
  33 #include <stdio.h>
  34 #include <string.h>
  35 #include <unistd.h>
  36 #include <errno.h>
  37
  38 #include "asterisk/lock.h"
  39 #include "asterisk/file.h"
  40 #include "asterisk/logger.h"
  41 #include "asterisk/channel.h"
  42 #include "asterisk/pbx.h"
  43 #include "asterisk/module.h"
  44 #include "asterisk/utils.h"
  45
  46 static char *app = "Milliwatt";
  47
  48 static char *synopsis = "Generate a Constant 1000Hz tone at 0dbm (mu-law)";
  49
  50 static char *descrip =
  51 "Milliwatt(): Generate a Constant 1000Hz tone at 0dbm (mu-law)\n";
  52
  53
  54 static char digital_milliwatt[] = {0x1e,0x0b,0x0b,0x1e,0x9e,0x8b,0x8b,0x9e} ;
  55
  56 static void *milliwatt_alloc(struct ast_channel *chan, void *params)
  57 {
  58         return ast_calloc(1, sizeof(int));
  59 }
  60
  61 static void milliwatt_release(struct ast_channel *chan, void *data)
  62 {
  63         free(data);
  64         return;
  65 }
  66
  67 static int milliwatt_generate(struct ast_channel *chan, void *data, int len, int samples)
  68 {
  69         unsigned char buf[AST_FRIENDLY_OFFSET + 640];
  70         const int maxsamples = sizeof (buf) / sizeof (buf[0]);
  71         int i, *indexp = (int *) data;
  72         struct ast_frame wf = {
  73                 .frametype = AST_FRAME_VOICE,
  74                 .subclass = AST_FORMAT_ULAW,
  75                 .offset = AST_FRIENDLY_OFFSET,
  76                 .data = buf + AST_FRIENDLY_OFFSET,
  77                 .src = __FUNCTION__,
  78         };
  79
  80         /* Instead of len, use samples, because channel.c generator_force
  81         * generate(chan, tmp, 0, 160) ignores len. In any case, len is
  82         * a multiple of samples, given by number of samples times bytes per
  83         * sample. In the case of ulaw, len = samples. for signed linear
  84         * len = 2 * samples */
  85
  86         if (samples > maxsamples) {
  87                 ast_log(LOG_WARNING, "Only doing %d samples (%d requested)\n", maxsamples, samples);
  88                 samples = maxsamples;
  89         }
  90         len = samples * sizeof (buf[0]);
  91         wf.datalen = len;
  92         wf.samples = samples;
  93         /* create a buffer containing the digital milliwatt pattern */
  94         for(i = 0; i < len; i++)
  95         {
  96                 buf[AST_FRIENDLY_OFFSET + i] = digital_milliwatt[(*indexp)++];
  97                 *indexp &= 7;
  98         }
  99         if (ast_write(chan,&wf) < 0)
 100         {
 101                 ast_log(LOG_WARNING,"Failed to write frame to '%s': %s\n",chan->name,strerror(errno));
 102                 return -1;
 103         }
 104         return 0;
 105 }
 106
 107 static struct ast_generator milliwattgen =
 108 {
 109         alloc: milliwatt_alloc,
 110         release: milliwatt_release,
 111         generate: milliwatt_generate,
 112 } ;
 113
 114 static int milliwatt_exec(struct ast_channel *chan, void *data)
 115 {
 116
 117         struct ast_module_user *u;
 118         u = ast_module_user_add(chan);
 119         ast_set_write_format(chan, AST_FORMAT_ULAW);
 120         ast_set_read_format(chan, AST_FORMAT_ULAW);
 121         if (chan->_state != AST_STATE_UP)
 122         {
 123                 ast_answer(chan);
 124         }
 125         if (ast_activate_generator(chan,&milliwattgen,"milliwatt") < 0)
 126         {
 127                 ast_log(LOG_WARNING,"Failed to activate generator on '%s'\n",chan->name);
 128                 ast_module_user_remove(u);
 129                 return -1;
 130         }
 131         while(!ast_safe_sleep(chan, 10000));
 132         ast_deactivate_generator(chan);
 133         ast_module_user_remove(u);
 134         return -1;
 135 }
 136
 137 static int unload_module(void)
 138 {
 139         int res;
 140
 141         res = ast_unregister_application(app);
 142
 143         ast_module_user_hangup_all();
 144
 145         return res;
 146 }
 147
 148 static int load_module(void)
 149 {
 150         return ast_register_application(app, milliwatt_exec, synopsis, descrip);
 151 }
 152
 153 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Digital Milliwatt (mu-law) Test Application");