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Asterisk developer's documentation


func_audiohookinherit.c
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1 /*
2  * Asterisk -- An open source telephony toolkit.
3  *
4  * Copyright (C) 2008, Digium, Inc.
5  *
6  * Mark Michelson <mmichelson@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  * Please follow coding guidelines
19  * http://svn.digium.com/view/asterisk/trunk/doc/CODING-GUIDELINES
20  */
21 
22 /*! \file
23  *
24  * \brief Audiohook inheritance function
25  *
26  * \author Mark Michelson <mmichelson@digium.com>
27  *
28  * \ingroup functions
29  */
30 
31 /*** MODULEINFO
32  <support_level>core</support_level>
33  ***/
34 
35 #include "asterisk.h"
36 #include "asterisk/datastore.h"
37 #include "asterisk/channel.h"
38 #include "asterisk/logger.h"
39 #include "asterisk/audiohook.h"
40 #include "asterisk/pbx.h"
41 #include "asterisk/module.h"
42 
43 /*** DOCUMENTATION
44  <function name = "AUDIOHOOK_INHERIT" language="en_US">
45  <synopsis>
46  Set whether an audiohook may be inherited to another channel
47  </synopsis>
48  <syntax>
49  <parameter name="source" required="true">
50  <para>The built-in sources in Asterisk are</para>
51  <enumlist>
52  <enum name="MixMonitor" />
53  <enum name="Chanspy" />
54  <enum name="Volume" />
55  <enum name="Speex" />
56  <enum name="pitch_shift" />
57  <enum name="JACK_HOOK" />
58  <enum name="Mute" />
59  </enumlist>
60  <para>Note that the names are not case-sensitive</para>
61  </parameter>
62  </syntax>
63  <description>
64  <para>By enabling audiohook inheritance on the channel, you are giving
65  permission for an audiohook to be inherited by a descendent channel.
66  Inheritance may be be disabled at any point as well.</para>
67 
68  <para>Example scenario:</para>
69  <para>exten => 2000,1,MixMonitor(blah.wav)</para>
70  <para>exten => 2000,n,Set(AUDIOHOOK_INHERIT(MixMonitor)=yes)</para>
71  <para>exten => 2000,n,Dial(SIP/2000)</para>
72  <para>
73  </para>
74  <para>exten => 4000,1,Dial(SIP/4000)</para>
75  <para>
76  </para>
77  <para>exten => 5000,1,MixMonitor(blah2.wav)</para>
78  <para>exten => 5000,n,Dial(SIP/5000)</para>
79  <para>
80  </para>
81  <para>In this basic dialplan scenario, let's consider the following sample calls</para>
82  <para>Call 1: Caller dials 2000. The person who answers then executes an attended</para>
83  <para> transfer to 4000.</para>
84  <para>Result: Since extension 2000 set MixMonitor to be inheritable, after the</para>
85  <para> transfer to 4000 has completed, the call will continue to be recorded
86  to blah.wav</para>
87  <para>
88  </para>
89  <para>Call 2: Caller dials 5000. The person who answers then executes an attended</para>
90  <para> transfer to 4000.</para>
91  <para>Result: Since extension 5000 did not set MixMonitor to be inheritable, the</para>
92  <para> recording will stop once the call has been transferred to 4000.</para>
93  </description>
94  </function>
95  ***/
96 
99  char source[1];
100 };
101 
104 };
105 
106 static void audiohook_inheritance_fixup(void *data, struct ast_channel *old_chan, struct ast_channel *new_chan);
107 static void audiohook_inheritance_destroy (void *data);
109  .type = "audiohook inheritance",
111  .chan_fixup = audiohook_inheritance_fixup,
112 };
113 
114 /*! \brief Move audiohooks as defined by previous calls to the AUDIOHOOK_INHERIT function
115  *
116  * Move allowed audiohooks from the old channel to the new channel.
117  *
118  * \param data The ast_datastore containing audiohook inheritance information that will be moved
119  * \param old_chan The "clone" channel from a masquerade. We are moving the audiohook in question off of this channel
120  * \param new_chan The "original" channel from a masquerade. We are moving the audiohook in question to this channel
121  * \return Void
122  */
123 static void audiohook_inheritance_fixup(void *data, struct ast_channel *old_chan, struct ast_channel *new_chan)
124 {
125  struct inheritable_audiohook *audiohook = NULL;
126  struct audiohook_inheritance_datastore *datastore = data;
127 
128  ast_debug(2, "inheritance fixup occurring for channels %s(%p) and %s(%p)", old_chan->name, old_chan, new_chan->name, new_chan);
129 
130  AST_LIST_TRAVERSE(&datastore->allowed_list, audiohook, list) {
131  ast_audiohook_move_by_source(old_chan, new_chan, audiohook->source);
132  ast_debug(3, "Moved audiohook %s from %s(%p) to %s(%p)\n",
133  audiohook->source, old_chan->name, old_chan, new_chan->name, new_chan);
134  }
135  return;
136 }
137 
138 /*! \brief Destroy dynamically allocated data on an audiohook_inheritance_datastore
139  *
140  * \param data Pointer to the audiohook_inheritance_datastore in question.
141  * \return Void
142  */
143 static void audiohook_inheritance_destroy(void *data)
144 {
145  struct audiohook_inheritance_datastore *audiohook_inheritance_datastore = data;
147 
148  while ((inheritable_audiohook = AST_LIST_REMOVE_HEAD(&audiohook_inheritance_datastore->allowed_list, list))) {
149  ast_free(inheritable_audiohook);
150  }
151 
152  ast_free(audiohook_inheritance_datastore);
153 }
154 
155 /*! \brief create an audiohook_inheritance_datastore and attach it to a channel
156  *
157  * \param chan The channel to which we wish to attach the new datastore
158  * \return Returns the newly created audiohook_inheritance_datastore or NULL on error
159  */
160 static struct audiohook_inheritance_datastore *setup_inheritance_datastore(struct ast_channel *chan)
161 {
162  struct ast_datastore *datastore = NULL;
163  struct audiohook_inheritance_datastore *audiohook_inheritance_datastore = NULL;
164 
165  if (!(datastore = ast_datastore_alloc(&audiohook_inheritance_info, NULL))) {
166  return NULL;
167  }
168 
169  if (!(audiohook_inheritance_datastore = ast_calloc(1, sizeof(*audiohook_inheritance_datastore)))) {
170  ast_datastore_free(datastore);
171  return NULL;
172  }
173 
174  datastore->data = audiohook_inheritance_datastore;
175  ast_channel_lock(chan);
176  ast_channel_datastore_add(chan, datastore);
177  ast_channel_unlock(chan);
178  return audiohook_inheritance_datastore;
179 }
180 
181 /*! \brief Create a new inheritable_audiohook structure and add it to an audiohook_inheritance_datastore
182  *
183  * \param audiohook_inheritance_datastore The audiohook_inheritance_datastore we want to add the new inheritable_audiohook to
184  * \param source The audiohook source for the newly created inheritable_audiohook
185  * \retval 0 Success
186  * \retval non-zero Failure
187  */
188 static int setup_inheritable_audiohook(struct audiohook_inheritance_datastore *audiohook_inheritance_datastore, const char *source)
189 {
191 
192  inheritable_audiohook = ast_calloc(1, sizeof(*inheritable_audiohook) + strlen(source));
193 
194  if (!inheritable_audiohook) {
195  return -1;
196  }
197 
198  strcpy(inheritable_audiohook->source, source);
199  AST_LIST_INSERT_TAIL(&audiohook_inheritance_datastore->allowed_list, inheritable_audiohook, list);
200  ast_debug(3, "Set audiohook %s to be inheritable\n", source);
201  return 0;
202 }
203 
204 /*! \brief Set the permissibility of inheritance for a particular audiohook source on a channel
205  *
206  * For details regarding what happens in the function, see the inline comments
207  *
208  * \param chan The channel we are operating on
209  * \param function The name of the dialplan function (AUDIOHOOK_INHERIT)
210  * \param data The audiohook source for which we are setting inheritance permissions
211  * \param value The value indicating the permission for audiohook inheritance
212  */
213 static int func_inheritance_write(struct ast_channel *chan, const char *function, char *data, const char *value)
214 {
215  int allow;
216  struct ast_datastore *datastore = NULL;
217  struct audiohook_inheritance_datastore *inheritance_datastore = NULL;
219 
220  /* Step 1: Get data from function call */
221  if (ast_strlen_zero(data)) {
222  ast_log(LOG_WARNING, "No argument provided to INHERITANCE function.\n");
223  return -1;
224  }
225 
226  if (ast_strlen_zero(value)) {
227  ast_log(LOG_WARNING, "No value provided to INHERITANCE function.\n");
228  return -1;
229  }
230 
231  if (!chan) {
232  ast_log(LOG_WARNING, "No channel was provided to INHERITANCE function.\n");
233  return -1;
234  }
235 
236  allow = ast_true(value);
237 
238  /* Step 2: retrieve or set up datastore */
239  ast_channel_lock(chan);
240  if (!(datastore = ast_channel_datastore_find(chan, &audiohook_inheritance_info, NULL))) {
241  ast_channel_unlock(chan);
242  /* In the case where we cannot find the datastore, we can take a few shortcuts */
243  if (!allow) {
244  ast_debug(1, "Audiohook %s is already set to not be inheritable on channel %s\n", data, chan->name);
245  return 0;
246  } else if (!(inheritance_datastore = setup_inheritance_datastore(chan))) {
247  ast_log(LOG_WARNING, "Unable to set up audiohook inheritance datastore on channel %s\n", chan->name);
248  return -1;
249  } else {
250  return setup_inheritable_audiohook(inheritance_datastore, data);
251  }
252  } else {
253  inheritance_datastore = datastore->data;
254  }
255  ast_channel_unlock(chan);
256 
257  /* Step 3: Traverse the list to see if we're trying something redundant */
258 
259  AST_LIST_TRAVERSE_SAFE_BEGIN(&inheritance_datastore->allowed_list, inheritable_audiohook, list) {
260  if (!strcasecmp(inheritable_audiohook->source, data)) {
261  if (allow) {
262  ast_debug(2, "Audiohook source %s is already set up to be inherited from channel %s\n", data, chan->name);
263  return 0;
264  } else {
265  ast_debug(2, "Removing inheritability of audiohook %s from channel %s\n", data, chan->name);
267  ast_free(inheritable_audiohook);
268  return 0;
269  }
270  }
271  }
273 
274  /* Step 4: There is no step 4 */
275 
276  /* Step 5: This means we are addressing an audiohook source which we have not encountered yet for the channel. Create a new inheritable
277  * audiohook structure if we're allowing inheritance, or just return if not
278  */
279 
280  if (allow) {
281  return setup_inheritable_audiohook(inheritance_datastore, data);
282  } else {
283  ast_debug(1, "Audiohook %s is already set to not be inheritable on channel %s\n", data, chan->name);
284  return 0;
285  }
286 }
287 
289  .name = "AUDIOHOOK_INHERIT",
290  .write = func_inheritance_write,
291 };
292 
293 static int unload_module(void)
294 {
295  return ast_custom_function_unregister(&inheritance_function);
296 }
297 
298 static int load_module(void)
299 {
300  if (ast_custom_function_register(&inheritance_function)) {
302  } else {
304  }
305 }
306 AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Audiohook inheritance function");
const char * type
Definition: datastore.h:32
static struct ast_datastore_info audiohook_inheritance_info
#define ast_channel_lock(chan)
Definition: channel.h:2466
Main Channel structure associated with a channel.
Definition: channel.h:742
void ast_audiohook_move_by_source(struct ast_channel *old_chan, struct ast_channel *new_chan, const char *source)
Move an audiohook from one channel to a new one.
Definition: audiohook.c:480
#define AST_MODULE_INFO_STANDARD(keystr, desc)
Definition: module.h:396
static int func_inheritance_write(struct ast_channel *chan, const char *function, char *data, const char *value)
Set the permissibility of inheritance for a particular audiohook source on a channel.
Asterisk main include file. File version handling, generic pbx functions.
#define AST_LIST_HEAD(name, type)
Defines a structure to be used to hold a list of specified type.
Definition: linkedlists.h:172
struct audiohook_inheritance_datastore::@130 allowed_list
struct inheritable_audiohook::@129 list
#define LOG_WARNING
Definition: logger.h:144
Audiohooks Architecture.
Structure for a data store type.
Definition: datastore.h:31
static int setup_inheritable_audiohook(struct audiohook_inheritance_datastore *audiohook_inheritance_datastore, const char *source)
Create a new inheritable_audiohook structure and add it to an audiohook_inheritance_datastore.
Structure for a data store object.
Definition: datastore.h:54
struct ast_datastore * ast_channel_datastore_find(struct ast_channel *chan, const struct ast_datastore_info *info, const char *uid)
Find a datastore on a channel.
Definition: channel.c:2604
static int load_module(void)
int value
Definition: syslog.c:39
#define AST_LIST_TRAVERSE_SAFE_END
Closes a safe loop traversal block.
Definition: linkedlists.h:600
static struct ast_custom_function inheritance_function
static void audiohook_inheritance_destroy(void *data)
Destroy dynamically allocated data on an audiohook_inheritance_datastore.
int ast_custom_function_unregister(struct ast_custom_function *acf)
Unregister a custom function.
Definition: pbx.c:3814
int ast_datastore_free(struct ast_datastore *datastore)
Free a data store object.
Definition: datastore.c:65
Asterisk datastore objects.
static struct audiohook_inheritance_datastore * setup_inheritance_datastore(struct ast_channel *chan)
create an audiohook_inheritance_datastore and attach it to a channel
#define ast_debug(level,...)
Log a DEBUG message.
Definition: logger.h:236
General Asterisk PBX channel definitions.
static force_inline int attribute_pure ast_strlen_zero(const char *s)
Definition: strings.h:63
Data structure associated with a custom dialplan function.
Definition: pbx.h:95
#define AST_LIST_REMOVE_CURRENT(field)
Removes the current entry from a list during a traversal.
Definition: linkedlists.h:554
#define AST_LIST_REMOVE_HEAD(head, field)
Removes and returns the head entry from a list.
Definition: linkedlists.h:818
Core PBX routines and definitions.
#define AST_LIST_INSERT_TAIL(head, elm, field)
Appends a list entry to the tail of a list.
Definition: linkedlists.h:716
int attribute_pure ast_true(const char *val)
Make sure something is true. Determine if a string containing a boolean value is &quot;true&quot;. This function checks to see whether a string passed to it is an indication of an &quot;true&quot; value. It checks to see if the string is &quot;yes&quot;, &quot;true&quot;, &quot;y&quot;, &quot;t&quot;, &quot;on&quot; or &quot;1&quot;.
Definition: utils.c:1533
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
struct ast_datastore * ast_datastore_alloc(const struct ast_datastore_info *info, const char *uid)
Definition: datastore.c:98
#define AST_LIST_TRAVERSE(head, var, field)
Loops over (traverses) the entries in a list.
Definition: linkedlists.h:490
#define AST_LIST_ENTRY(type)
Declare a forward link structure inside a list entry.
Definition: linkedlists.h:409
#define ast_channel_unlock(chan)
Definition: channel.h:2467
#define ast_free(a)
Definition: astmm.h:97
static void audiohook_inheritance_fixup(void *data, struct ast_channel *old_chan, struct ast_channel *new_chan)
Move audiohooks as defined by previous calls to the AUDIOHOOK_INHERIT function.
Support for logging to various files, console and syslog Configuration in file logger.conf.
void * data
Definition: datastore.h:56
#define ast_calloc(a, b)
Definition: astmm.h:82
const char * name
Definition: pbx.h:96
#define AST_LIST_TRAVERSE_SAFE_BEGIN(head, var, field)
Loops safely over (traverses) the entries in a list.
Definition: linkedlists.h:528
#define ASTERISK_GPL_KEY
The text the key() function should return.
Definition: module.h:38
Asterisk module definitions.
int ast_channel_datastore_add(struct ast_channel *chan, struct ast_datastore *datastore)
Add a datastore to a channel.
Definition: channel.c:2590
static int unload_module(void)
#define ast_custom_function_register(acf)
Register a custom function.
Definition: pbx.h:1164