Merged revisions 89886 via svnmerge from
[asterisk/asterisk.git] / main / autoservice.c
1 /*
2  * Asterisk -- An open source telephony toolkit.
3  *
4  * Copyright (C) 1999 - 2006, 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 Automatic channel service routines
22  *
23  * \author Mark Spencer <markster@digium.com> 
24  */
25
26 #include "asterisk.h"
27
28 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
29
30 #include <sys/time.h>
31 #include <signal.h>
32
33 #include "asterisk/pbx.h"
34 #include "asterisk/frame.h"
35 #include "asterisk/sched.h"
36 #include "asterisk/channel.h"
37 #include "asterisk/file.h"
38 #include "asterisk/translate.h"
39 #include "asterisk/manager.h"
40 #include "asterisk/chanvars.h"
41 #include "asterisk/linkedlists.h"
42 #include "asterisk/indications.h"
43 #include "asterisk/lock.h"
44 #include "asterisk/utils.h"
45
46 #define MAX_AUTOMONS 256
47
48 struct asent {
49         struct ast_channel *chan;
50         /*! This gets incremented each time autoservice gets started on the same
51          *  channel.  It will ensure that it doesn't actually get stopped until 
52          *  it gets stopped for the last time. */
53         unsigned int use_count;
54         AST_LIST_HEAD_NOLOCK(, ast_frame) dtmf_frames;
55         AST_LIST_ENTRY(asent) list;
56 };
57
58 static AST_RWLIST_HEAD_STATIC(aslist, asent);
59
60 static pthread_t asthread = AST_PTHREADT_NULL;
61
62 static void *autoservice_run(void *ign)
63 {
64
65         for (;;) {
66                 struct ast_channel *mons[MAX_AUTOMONS], *chan;
67                 struct asent *as;
68                 int x = 0, ms = 500;
69
70                 AST_RWLIST_RDLOCK(&aslist);
71                 AST_RWLIST_TRAVERSE(&aslist, as, list) {
72                         if (!ast_check_hangup(as->chan)) {
73                                 if (x < MAX_AUTOMONS)
74                                         mons[x++] = as->chan;
75                                 else
76                                         ast_log(LOG_WARNING, "Exceeded maximum number of automatic monitoring events.  Fix autoservice.c\n");
77                         }
78                 }
79                 AST_RWLIST_UNLOCK(&aslist);
80
81                 if ((chan = ast_waitfor_n(mons, x, &ms))) {
82                         struct ast_frame *f = ast_read(chan);
83         
84                         if (!f)
85                                 continue;
86                         
87                         /* Do not add a default entry in this switch statement.  Each new
88                          * frame type should be addressed directly as to whether it should
89                          * be queued up or not. */
90                         switch (f->frametype) {
91                         /* Save these frames */
92                         case AST_FRAME_DTMF_BEGIN:
93                         case AST_FRAME_DTMF_END:
94                         case AST_FRAME_CONTROL:
95                         case AST_FRAME_TEXT:
96                         case AST_FRAME_IMAGE:
97                         case AST_FRAME_HTML:
98                         {
99                                 struct ast_frame *dup_f;
100
101                                 AST_RWLIST_WRLOCK(&aslist);
102                                 AST_RWLIST_TRAVERSE(&aslist, as, list) {
103                                         if (as->chan != chan)
104                                                 continue;
105                                         if ((dup_f = ast_frdup(f)))
106                                                 AST_LIST_INSERT_TAIL(&as->dtmf_frames, dup_f, frame_list);
107                                 }
108                                 AST_RWLIST_UNLOCK(&aslist);
109                         }
110
111                         /* Throw these frames away */
112                         case AST_FRAME_VOICE:
113                         case AST_FRAME_VIDEO:
114                         case AST_FRAME_NULL:
115                         case AST_FRAME_IAX:
116                         case AST_FRAME_CNG:
117                         case AST_FRAME_MODEM:
118                                 break;
119                         }
120
121                         if (f)
122                                 ast_frfree(f);
123                 }
124         }
125
126         asthread = AST_PTHREADT_NULL;
127
128         return NULL;
129 }
130
131 int ast_autoservice_start(struct ast_channel *chan)
132 {
133         int res = -1;
134         struct asent *as;
135
136         AST_RWLIST_WRLOCK(&aslist);
137
138         /* Check if the channel already has autoservice */
139         AST_RWLIST_TRAVERSE(&aslist, as, list) {
140                 if (as->chan == chan) {
141                         as->use_count++;
142                         break;
143                 }
144         }
145
146         /* If not, start autoservice on channel */
147         if (!as && (as = ast_calloc(1, sizeof(*as)))) {
148                 as->chan = chan;
149                 as->use_count = 1;
150                 AST_RWLIST_INSERT_HEAD(&aslist, as, list);
151                 res = 0;
152                 if (asthread == AST_PTHREADT_NULL) { /* need start the thread */
153                         if (ast_pthread_create_background(&asthread, NULL, autoservice_run, NULL)) {
154                                 ast_log(LOG_WARNING, "Unable to create autoservice thread :(\n");
155                                 /* There will only be a single member in the list at this point,
156                                    the one we just added. */
157                                 AST_RWLIST_REMOVE(&aslist, as, list);
158                                 ast_free(as);
159                                 res = -1;
160                         } else
161                                 pthread_kill(asthread, SIGURG);
162                 }
163         }
164
165         AST_RWLIST_UNLOCK(&aslist);
166
167         return res;
168 }
169
170 int ast_autoservice_stop(struct ast_channel *chan)
171 {
172         int res = -1;
173         struct asent *as;
174         AST_LIST_HEAD_NOLOCK(, ast_frame) dtmf_frames;
175         struct ast_frame *f;
176         int removed = 1;
177
178         AST_LIST_HEAD_INIT_NOLOCK(&dtmf_frames);
179
180         AST_RWLIST_WRLOCK(&aslist);
181         AST_RWLIST_TRAVERSE_SAFE_BEGIN(&aslist, as, list) {     
182                 if (as->chan == chan) {
183                         AST_RWLIST_REMOVE_CURRENT(list);
184                         as->use_count--;
185                         if (as->use_count) {
186                                 removed = 0;
187                                 break;
188                         }
189                         AST_LIST_APPEND_LIST(&dtmf_frames, &as->dtmf_frames, frame_list);
190                         ast_free(as);
191                         if (!ast_check_hangup(chan))
192                                 res = 0;
193                         break;
194                 }
195         }
196         AST_RWLIST_TRAVERSE_SAFE_END;
197
198         if (removed && asthread != AST_PTHREADT_NULL) 
199                 pthread_kill(asthread, SIGURG);
200         
201         AST_RWLIST_UNLOCK(&aslist);
202
203         if (!removed)
204                 return 0;
205
206         /* Wait for it to un-block */
207         while (ast_test_flag(chan, AST_FLAG_BLOCKING))
208                 usleep(1000);
209
210         while ((f = AST_LIST_REMOVE_HEAD(&dtmf_frames, frame_list))) {
211                 ast_queue_frame(chan, f);
212                 ast_frfree(f);
213         }
214
215         return res;
216 }