Wed Jan 8 2020 09:49:40

Asterisk developer's documentation


app_milliwatt.c
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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 /*** MODULEINFO
29  <support_level>core</support_level>
30  ***/
31 
32 #include "asterisk.h"
33 
34 ASTERISK_FILE_VERSION(__FILE__, "$Revision: 361142 $")
35 
36 #include "asterisk/module.h"
37 #include "asterisk/channel.h"
38 #include "asterisk/pbx.h"
39 #include "asterisk/indications.h"
40 
41 /*** DOCUMENTATION
42  <application name="Milliwatt" language="en_US">
43  <synopsis>
44  Generate a Constant 1004Hz tone at 0dbm (mu-law).
45  </synopsis>
46  <syntax>
47  <parameter name="options">
48  <optionlist>
49  <option name="o">
50  <para>Generate the tone at 1000Hz like previous version.</para>
51  </option>
52  </optionlist>
53  </parameter>
54  </syntax>
55  <description>
56  <para>Previous versions of this application generated the tone at 1000Hz. If for
57  some reason you would prefer that behavior, supply the <literal>o</literal> option to get the
58  old behavior.</para>
59  </description>
60  </application>
61  ***/
62 
63 static const char app[] = "Milliwatt";
64 
65 static const char digital_milliwatt[] = {0x1e,0x0b,0x0b,0x1e,0x9e,0x8b,0x8b,0x9e} ;
66 
67 static void *milliwatt_alloc(struct ast_channel *chan, void *params)
68 {
69  return ast_calloc(1, sizeof(int));
70 }
71 
72 static void milliwatt_release(struct ast_channel *chan, void *data)
73 {
74  ast_free(data);
75  return;
76 }
77 
78 static int milliwatt_generate(struct ast_channel *chan, void *data, int len, int samples)
79 {
80  unsigned char buf[AST_FRIENDLY_OFFSET + 640];
81  const int maxsamples = ARRAY_LEN(buf) - (AST_FRIENDLY_OFFSET / sizeof(buf[0]));
82  int i, *indexp = (int *) data;
83  struct ast_frame wf = {
85  .subclass.codec = AST_FORMAT_ULAW,
86  .offset = AST_FRIENDLY_OFFSET,
87  .src = __FUNCTION__,
88  };
89  wf.data.ptr = buf + AST_FRIENDLY_OFFSET;
90 
91  /* Instead of len, use samples, because channel.c generator_force
92  * generate(chan, tmp, 0, 160) ignores len. In any case, len is
93  * a multiple of samples, given by number of samples times bytes per
94  * sample. In the case of ulaw, len = samples. for signed linear
95  * len = 2 * samples */
96  if (samples > maxsamples) {
97  ast_log(LOG_WARNING, "Only doing %d samples (%d requested)\n", maxsamples, samples);
98  samples = maxsamples;
99  }
100 
101  len = samples * sizeof (buf[0]);
102  wf.datalen = len;
103  wf.samples = samples;
104 
105  /* create a buffer containing the digital milliwatt pattern */
106  for (i = 0; i < len; i++) {
107  buf[AST_FRIENDLY_OFFSET + i] = digital_milliwatt[(*indexp)++];
108  *indexp &= 7;
109  }
110 
111  if (ast_write(chan,&wf) < 0) {
112  ast_log(LOG_WARNING,"Failed to write frame to '%s': %s\n",chan->name,strerror(errno));
113  return -1;
114  }
115 
116  return 0;
117 }
118 
119 static struct ast_generator milliwattgen = {
121  .release = milliwatt_release,
122  .generate = milliwatt_generate,
123 };
124 
125 static int old_milliwatt_exec(struct ast_channel *chan)
126 {
129 
130  if (chan->_state != AST_STATE_UP) {
131  ast_answer(chan);
132  }
133 
134  if (ast_activate_generator(chan,&milliwattgen,"milliwatt") < 0) {
135  ast_log(LOG_WARNING,"Failed to activate generator on '%s'\n",chan->name);
136  return -1;
137  }
138 
139  while (!ast_safe_sleep(chan, 10000))
140  ;
141 
143 
144  return -1;
145 }
146 
147 static int milliwatt_exec(struct ast_channel *chan, const char *data)
148 {
149  const char *options = data;
150  int res = -1;
151 
152  if (!ast_strlen_zero(options) && strchr(options, 'o')) {
153  return old_milliwatt_exec(chan);
154  }
155 
156  res = ast_playtones_start(chan, 23255, "1004/1000", 0);
157 
158  while (!res) {
159  res = ast_safe_sleep(chan, 10000);
160  }
161 
162  return res;
163 }
164 
165 static int unload_module(void)
166 {
167  return ast_unregister_application(app);
168 }
169 
170 static int load_module(void)
171 {
173 }
174 
175 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Digital Milliwatt (mu-law) Test Application");
int ast_safe_sleep(struct ast_channel *chan, int ms)
Wait for a specified amount of time, looking for hangups.
Definition: channel.c:1916
Tone Indication Support.
Main Channel structure associated with a channel.
Definition: channel.h:742
#define AST_MODULE_INFO_STANDARD(keystr, desc)
Definition: module.h:396
Asterisk main include file. File version handling, generic pbx functions.
#define ARRAY_LEN(a)
Definition: isdn_lib.c:42
static int unload_module(void)
int ast_activate_generator(struct ast_channel *chan, struct ast_generator *gen, void *params)
Definition: channel.c:3148
void * ptr
Definition: frame.h:160
#define LOG_WARNING
Definition: logger.h:144
int ast_unregister_application(const char *app)
Unregister an application.
Definition: pbx.c:7705
int ast_set_write_format(struct ast_channel *chan, format_t format)
Sets write format on channel chan Set write format for channel to whichever component of &quot;format&quot; is ...
Definition: channel.c:5307
int ast_set_read_format(struct ast_channel *chan, format_t format)
Sets read format on channel chan Set read format for channel to whichever component of &quot;format&quot; is be...
Definition: channel.c:5301
General Asterisk PBX channel definitions.
#define AST_FRIENDLY_OFFSET
Offset into a frame&#39;s data buffer.
Definition: frame.h:204
static force_inline int attribute_pure ast_strlen_zero(const char *s)
Definition: strings.h:63
int datalen
Definition: frame.h:148
static int load_module(void)
static int milliwatt_generate(struct ast_channel *chan, void *data, int len, int samples)
Definition: app_milliwatt.c:78
static void * milliwatt_alloc(struct ast_channel *chan, void *params)
Definition: app_milliwatt.c:67
Core PBX routines and definitions.
static void milliwatt_release(struct ast_channel *chan, void *data)
Definition: app_milliwatt.c:72
#define AST_FORMAT_ULAW
Definition: frame.h:246
static const char digital_milliwatt[]
Definition: app_milliwatt.c:65
static int len(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t buflen)
enum ast_channel_state _state
Definition: channel.h:839
const ast_string_field name
Definition: channel.h:787
void ast_log(int level, const char *file, int line, const char *function, const char *fmt,...)
Used for sending a log message This is the standard logger function. Probably the only way you will i...
Definition: logger.c:1207
void *(* alloc)(struct ast_channel *chan, void *params)
Definition: channel.h:180
int errno
#define ast_free(a)
Definition: astmm.h:97
int ast_write(struct ast_channel *chan, struct ast_frame *frame)
Write a frame to a channel This function writes the given frame to the indicated channel.
Definition: channel.c:4916
static struct ast_generator milliwattgen
static int milliwatt_exec(struct ast_channel *chan, const char *data)
void ast_deactivate_generator(struct ast_channel *chan)
Definition: channel.c:3107
#define ast_calloc(a, b)
Definition: astmm.h:82
int ast_answer(struct ast_channel *chan)
Answer a channel.
Definition: channel.c:3086
Data structure associated with a single frame of data.
Definition: frame.h:142
int ast_playtones_start(struct ast_channel *chan, int vol, const char *tonelist, int interruptible)
Start playing a list of tones on a channel.
Definition: indications.c:319
enum ast_frame_type frametype
Definition: frame.h:144
#define ASTERISK_GPL_KEY
The text the key() function should return.
Definition: module.h:38
static const char app[]
Definition: app_milliwatt.c:63
static int old_milliwatt_exec(struct ast_channel *chan)
union ast_frame::@172 data
#define ast_register_application_xml(app, execute)
Register an application using XML documentation.
Definition: module.h:437
#define ASTERISK_FILE_VERSION(file, version)
Register/unregister a source code file with the core.
Definition: asterisk.h:180
int samples
Definition: frame.h:150