8695414eafb7605f32c4e2d90e4515a081941c09
[asterisk/asterisk.git] / res / res_fax.c
1 /*
2  * Asterisk -- An open source telephony toolkit.
3  *
4  * Copyright (C) 2008-2009, Digium, Inc.
5  *
6  * Dwayne M. Hubbard <dhubbard@digium.com>
7  * Kevin P. Fleming <kpfleming@digium.com>
8  *
9  * See http://www.asterisk.org for more information about
10  * the Asterisk project. Please do not directly contact
11  * any of the maintainers of this project for assistance;
12  * the project provides a web site, mailing lists and IRC
13  * channels for your use.
14  *
15  * This program is free software, distributed under the terms of
16  * the GNU General Public License Version 2. See the LICENSE file
17  * at the top of the source tree.
18  */
19
20 /*** MODULEINFO
21         <conflict>app_fax</conflict>
22 ***/
23
24 /*! \file
25  *
26  * \brief Generic FAX Resource for FAX technology resource modules
27  *
28  * \author Dwayne M. Hubbard <dhubbard@digium.com>
29  * \author Kevin P. Fleming <kpfleming@digium.com>
30  * 
31  * A generic FAX resource module that provides SendFAX and ReceiveFAX applications.
32  * This module requires FAX technology modules, like res_fax_spandsp, to register with it
33  * so it can use the technology modules to perform the actual FAX transmissions.
34  * \ingroup applications
35  */
36
37 #include "asterisk.h"
38
39 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
40
41 #include "asterisk/io.h"
42 #include "asterisk/file.h"
43 #include "asterisk/logger.h"
44 #include "asterisk/module.h"
45 #include "asterisk/app.h"
46 #include "asterisk/lock.h"
47 #include "asterisk/options.h"
48 #include "asterisk/strings.h"
49 #include "asterisk/cli.h"
50 #include "asterisk/utils.h"
51 #include "asterisk/config.h"
52 #include "asterisk/astobj2.h"
53 #include "asterisk/res_fax.h"
54 #include "asterisk/file.h"
55 #include "asterisk/channel.h"
56 #include "asterisk/pbx.h"
57 #include "asterisk/manager.h"
58 #include "asterisk/dsp.h"
59 #include "asterisk/indications.h"
60 #include "asterisk/ast_version.h"
61
62 /*** DOCUMENTATION
63         <application name="ReceiveFax" language="en_US">
64                 <synopsis>
65                         Receive a FAX and save as a TIFF/F file.
66                 </synopsis>
67                 <syntax>
68                         <parameter name="filename" required="true" />
69                         <parameter name="options">
70                                 <optionlist>
71                                         <option name="d">
72                                                 <para>Enable FAX debugging.</para>
73                                         </option>
74                                         <option name="f">
75                                                 <para>Allow audio fallback FAX transfer on T.38 capable channels.</para>
76                                         </option>
77                                         <option name="s">
78                                                 <para>Send progress Manager events (overrides statusevents setting in res_fax.conf).</para>
79                                         </option>
80                                 </optionlist>
81                         </parameter>
82                 </syntax>
83                 <description>
84                         <para>This application is provided by res_fax, which is a FAX technology agnostic module
85                         that utilizes FAX technology resource modules to complete a FAX transmission.</para>
86                         <para>Session arguments can be set by the FAXOPT function and to check results of the ReceiveFax() application.</para>
87                 </description>
88                 <see-also>
89                         <ref type="function">FAXOPT</ref>
90                 </see-also>
91         </application>
92         <application name="SendeFax" language="en_US">
93                 <synopsis>
94                         Sends a specified TIFF/F file as a FAX.
95                 </synopsis>
96                 <syntax>
97                         <parameter name="filename" required="true" argsep="&amp;">
98                                 <argument name="filename2" multiple="true">
99                                         <para>TIFF file to send as a FAX.</para>
100                                 </argument>
101                         </parameter>
102                         <parameter name="options">
103                                 <optionlist>
104                                         <option name="d">
105                                                 <para>Enable FAX debugging.</para>
106                                         </option>
107                                         <option name="f">
108                                                 <para>Allow audio fallback FAX transfer on T.38 capable channels.</para>
109                                         </option>
110                                         <option name="s">
111                                                 <para>Send progress Manager events (overrides statusevents setting in res_fax.conf).</para>
112                                         </option>
113                                         <option name="z">
114                                                 <para>Initiate a T.38 reinvite on the channel if the remote end does not.</para>
115                                         </option>
116                                 </optionlist>
117                         </parameter>
118                 </syntax>
119                 <description>
120                         <para>This application is provided by res_fax, which is a FAX technology agnostic module
121                         that utilizes FAX technology resource modules to complete a FAX transmission.</para>
122                         <para>Session arguments can be set by the FAXOPT function and to check results of the SendFax() application.</para>
123                 </description>
124                 <see-also>
125                         <ref type="function">FAXOPT</ref>
126                 </see-also>
127         </application>
128         <function name="FAXOPT" language="en_US">
129                 <synopsis>
130                         Gets/sets various pieces of information about a fax session.
131                 </synopsis>
132                 <syntax>
133                         <parameter name="item" required="true">
134                                 <enumlist>
135                                         <enum name="ecm">
136                                                 <para>R/W Error Correction Mode (ECM) enable with 'yes', disable with 'no'.</para>
137                                         </enum>
138                                         <enum name="error">
139                                                 <para>R/O FAX transmission error code upon failure.</para>
140                                         </enum>
141                                         <enum name="filename">
142                                                 <para>R/O Filename of the first file of the FAX transmission.</para>
143                                         </enum>
144                                         <enum name="filenames">
145                                                 <para>R/O Filenames of all of the files in the FAX transmission (comma separated).</para>
146                                         </enum>
147                                         <enum name="headerinfo">
148                                                 <para>R/W FAX header information.</para>
149                                         </enum>
150                                         <enum name="localstationid">
151                                                 <para>R/W Local Station Identification.</para>
152                                         </enum>
153                                         <enum name="minrate">
154                                                 <para>R/W Minimum transfer rate set before transmission.</para>
155                                         </enum>
156                                         <enum name="maxrate">
157                                                 <para>R/W Maximum transfer rate set before transmission.</para>
158                                         </enum>
159                                         <enum name="modem">
160                                                 <para>R/W Modem type (v17/v27/v29).</para>
161                                         </enum>
162                                         <enum name="pages">
163                                                 <para>R/O Number of pages transferred.</para>
164                                         </enum>
165                                         <enum name="rate">
166                                                 <para>R/O Negotiated transmission rate.</para>
167                                         </enum>
168                                         <enum name="remotestationid">
169                                                 <para>R/O Remote Station Identification after transmission.</para>
170                                         </enum>
171                                         <enum name="resolution">
172                                                 <para>R/O Negotiated image resolution after transmission.</para>
173                                         </enum>
174                                         <enum name="sessionid">
175                                                 <para>R/O Session ID of the FAX transmission.</para>
176                                         </enum>
177                                         <enum name="status">
178                                                 <para>R/O Result Status of the FAX transmission.</para>
179                                         </enum>
180                                         <enum name="statusstr">
181                                                 <para>R/O Verbose Result Status of the FAX transmission.</para>
182                                         </enum>
183                                 </enumlist>
184                         </parameter>
185                 </syntax>
186                 <description>
187                         <para>FAXOPT can be used to override the settings for a FAX session listed in <filename>res_fax.conf</filename>,
188                         it can also be used to retreive information about a FAX session that has finished eg. pages/status.</para>
189                 </description>
190                 <see-also>
191                         <ref type="application">ReceiveFax</ref>
192                         <ref type="application">SendFax</ref>
193                 </see-also>
194         </function>
195 ***/
196
197 static const char app_receivefax[] = "ReceiveFAX";
198 static const char app_sendfax[] = "SendFAX";
199
200 struct debug_info_history {
201         unsigned int consec_frames;
202         unsigned int consec_ms;
203         unsigned char silence;
204 };
205
206 struct ast_fax_debug_info {
207         struct timeval base_tv;
208         struct debug_info_history c2s, s2c;
209         struct ast_dsp *dsp;
210 };
211
212 static int fax_logger_level = -1;
213
214 /*! \brief maximum buckets for res_fax ao2 containers */
215 #define FAX_MAXBUCKETS 10
216
217 #define RES_FAX_TIMEOUT 10000
218
219 /*! \brief The faxregistry is used to manage information and statistics for all FAX sessions. */
220 static struct {
221         /*! The number of active FAX sessions */
222         int active_sessions;
223         /*! active sessions are astobj2 objects */
224         struct ao2_container *container;
225         /*! Total number of Tx FAX attempts */
226         int fax_tx_attempts;
227         /*! Total number of Rx FAX attempts */
228         int fax_rx_attempts;
229         /*! Number of successful FAX transmissions */
230         int fax_complete;
231         /*! Number of failed FAX transmissions */
232         int fax_failures;
233         /*! the next unique session name */
234         int nextsessionname;
235 } faxregistry;
236
237 /*! \brief registered FAX technology modules are put into this list */
238 struct fax_module {
239         const struct ast_fax_tech *tech;
240         AST_RWLIST_ENTRY(fax_module) list;
241 };
242 static AST_RWLIST_HEAD_STATIC(faxmodules, fax_module);
243
244 #define RES_FAX_MINRATE 2400
245 #define RES_FAX_MAXRATE 14400
246 #define RES_FAX_STATUSEVENTS 0
247 #define RES_FAX_MODEM (AST_FAX_MODEM_V17 | AST_FAX_MODEM_V27 | AST_FAX_MODEM_V29)
248
249 static struct {
250         enum ast_fax_modems modems;
251         uint32_t statusevents:1;
252         uint32_t ecm:1;
253         unsigned int minrate;   
254         unsigned int maxrate;
255 } general_options;
256
257 static const char *config = "res_fax.conf";
258
259 static int global_fax_debug = 0;
260
261 enum {
262         OPT_CALLEDMODE  = (1 << 0),
263         OPT_CALLERMODE  = (1 << 1),
264         OPT_DEBUG       = (1 << 2),
265         OPT_STATUS      = (1 << 3),
266         OPT_ALLOWAUDIO  = (1 << 5),
267         OPT_REQUEST_T38 = (1 << 6),
268 };
269
270 AST_APP_OPTIONS(fax_exec_options, BEGIN_OPTIONS
271         AST_APP_OPTION('a', OPT_CALLEDMODE),
272         AST_APP_OPTION('c', OPT_CALLERMODE),
273         AST_APP_OPTION('d', OPT_DEBUG),
274         AST_APP_OPTION('f', OPT_ALLOWAUDIO),
275         AST_APP_OPTION('s', OPT_STATUS),
276         AST_APP_OPTION('z', OPT_REQUEST_T38),
277 END_OPTIONS);
278
279 struct manager_event_info {
280         char context[AST_MAX_CONTEXT];
281         char exten[AST_MAX_EXTENSION];
282         char cid[128];
283 };
284
285 static void debug_check_frame_for_silence(struct ast_fax_session *s, unsigned int c2s, struct ast_frame *frame)
286 {       
287         struct debug_info_history *history = c2s ? &s->debug_info->c2s : &s->debug_info->s2c;
288         int dspsilence;
289         unsigned int last_consec_frames, last_consec_ms;
290         unsigned char wassil;
291         struct timeval diff;
292
293         diff = ast_tvsub(ast_tvnow(), s->debug_info->base_tv);
294
295         ast_dsp_reset(s->debug_info->dsp);
296         ast_dsp_silence(s->debug_info->dsp, frame, &dspsilence);
297
298         wassil = history->silence;
299         history->silence = (dspsilence != 0) ? 1 : 0;
300         if (history->silence != wassil) {
301                 last_consec_frames = history->consec_frames;
302                 last_consec_ms = history->consec_ms;
303                 history->consec_frames = 0;
304                 history->consec_ms = 0;
305
306                 if ((last_consec_frames != 0)) {
307                         ast_verb(6, "Channel '%s' fax session '%d', [ %.3ld.%.6ld ], %s sent %d frames (%d ms) of %s.\n",
308                                  s->channame, s->id, (long) diff.tv_sec, (long int) diff.tv_usec,
309                                  (c2s) ? "channel" : "stack", last_consec_frames, last_consec_ms,
310                                  (wassil) ? "silence" : "energy");
311                 }
312         }
313
314         history->consec_frames++;
315         history->consec_ms += (frame->samples / 8);
316 }
317
318 static void destroy_callback(void *data) 
319 {
320         if (data) {
321                 ao2_ref(data, -1);
322         }
323 }
324
325 static const struct ast_datastore_info fax_datastore = {
326         .type = "res_fax",
327         .destroy = destroy_callback,
328 };
329
330 /*! \brief returns a reference counted pointer to a fax datastore, if it exists */
331 static struct ast_fax_session_details *find_details(struct ast_channel *chan)
332 {
333         struct ast_fax_session_details *details;
334         struct ast_datastore *datastore;
335
336         ast_channel_lock(chan); 
337         if (!(datastore = ast_channel_datastore_find(chan, &fax_datastore, NULL))) {
338                 ast_channel_unlock(chan);       
339                 return NULL;
340         }
341         if (!(details = datastore->data)) {
342                 ast_log(LOG_WARNING, "Huh?  channel '%s' has a FAX datastore without data!\n", chan->name);
343                 ast_channel_unlock(chan);
344                 return NULL;
345         }
346         ao2_ref(details, 1);    
347         ast_channel_unlock(chan);       
348
349         return details;
350 }
351
352 /*! \brief destroy a FAX session details structure */
353 static void destroy_session_details(void *details)
354 {
355         struct ast_fax_session_details *d = details;
356         struct ast_fax_document *doc;
357         
358         while ((doc = AST_LIST_REMOVE_HEAD(&d->documents, next))) {
359                 ast_free(doc);
360         }
361         ast_string_field_free_memory(d);        
362 }
363
364 /*! \brief create a FAX session details structure */
365 static struct ast_fax_session_details *session_details_new(void)
366 {
367         struct ast_fax_session_details *d;
368
369         if (!(d = ao2_alloc(sizeof(*d), destroy_session_details))) {
370                 return NULL;
371         }
372         
373         if (ast_string_field_init(d, 512)) {
374                 ao2_ref(d, -1);
375                 return NULL;
376         }
377
378         AST_LIST_HEAD_INIT_NOLOCK(&d->documents);
379
380         /* These options need to be set to the configured default and may be overridden by
381          * SendFAX, ReceiveFAX, or FAXOPT */
382         d->option.request_t38 = AST_FAX_OPTFLAG_FALSE;
383         d->option.send_cng = AST_FAX_OPTFLAG_FALSE;
384         d->option.send_ced = AST_FAX_OPTFLAG_FALSE;
385         d->option.ecm = general_options.ecm;
386         d->option.statusevents = general_options.statusevents;
387         d->modems = general_options.modems;
388         d->minrate = general_options.minrate;
389         d->maxrate = general_options.maxrate;
390         ast_string_field_set(d, result, "FAILED");
391         ast_string_field_set(d, resultstr, "error starting fax session");
392         ast_string_field_set(d, error, "INIT_ERROR");
393
394         return d;
395 }
396
397 /*! \brief returns a reference counted details structure from the channel's fax datastore.  If the datastore
398  * does not exist it will be created */ 
399 static struct ast_fax_session_details *find_or_create_details(struct ast_channel *chan)
400 {
401         struct ast_fax_session_details *details;
402         struct ast_datastore *datastore;
403
404         if ((details = find_details(chan))) {
405                 return details;
406         }
407         /* channel does not have one so we must create one */
408         if (!(details = session_details_new())) {
409                 ast_log(LOG_WARNING, "channel '%s' can't get a FAX details structure for the datastore!\n", chan->name);
410                 return NULL;
411         }
412         if (!(datastore = ast_datastore_alloc(&fax_datastore, NULL))) {
413                 ao2_ref(details, -1);
414                 ast_log(LOG_WARNING, "channel '%s' can't get a datastore!\n", chan->name);
415                 return NULL;
416         }
417         /* add the datastore to the channel and increment the refcount */
418         datastore->data = details;
419         ao2_ref(details, 1);
420         ast_channel_lock(chan);
421         ast_channel_datastore_add(chan, datastore);
422         ast_channel_unlock(chan);
423         return details;
424 }
425
426 unsigned int ast_fax_maxrate(void)
427 {
428         return general_options.maxrate;
429 }
430
431 unsigned int ast_fax_minrate(void)
432 {
433         return general_options.minrate;
434 }
435
436 static int update_modem_bits(enum ast_fax_modems *bits, const char *value)
437 {               
438         char *m[5], *tok, *v = (char *)value;
439         int i = 0, j;
440
441         if (!(tok = strchr(v, ','))) {
442                 m[i++] = v;
443                 m[i] = NULL;
444         } else {
445                 tok = strtok(v, ", ");
446                 while (tok && (i < 5)) {
447                         m[i++] = tok;
448                         tok = strtok(NULL, ", ");
449                 }
450                 m[i] = NULL;
451         }
452
453         *bits = 0;
454         for (j = 0; j < i; j++) {
455                 if (!strcasecmp(m[j], "v17")) {
456                         *bits |= AST_FAX_MODEM_V17;
457                 } else if (!strcasecmp(m[j], "v27")) {
458                         *bits |= AST_FAX_MODEM_V27;
459                 } else if (!strcasecmp(m[j], "v29")) {
460                         *bits |= AST_FAX_MODEM_V29;
461                 } else if (!strcasecmp(m[j], "v34")) {
462                         *bits |= AST_FAX_MODEM_V34;
463                 } else {
464                         ast_log(LOG_WARNING, "ignoring invalid modem setting: '%s', valid options {v17 | v27 | v29 | v34}\n", m[j]);
465                 }
466         }
467         return 0;
468 }
469
470 static int ast_fax_modem_to_str(enum ast_fax_modems bits, char *tbuf, size_t bufsize)
471 {
472         int count = 0;
473
474         if (bits & AST_FAX_MODEM_V17) {
475                 strcat(tbuf, "V17");
476                 count++;
477         }
478         if (bits & AST_FAX_MODEM_V27) {
479                 if (count) {
480                         strcat(tbuf, ",");
481                 }
482                 strcat(tbuf, "V27");
483                 count++;
484         }
485         if (bits & AST_FAX_MODEM_V29) {
486                 if (count) {
487                         strcat(tbuf, ",");
488                 }
489                 strcat(tbuf, "V29");
490                 count++;
491         }
492         if (bits & AST_FAX_MODEM_V34) {
493                 if (count) {
494                         strcat(tbuf, ",");
495                 }
496                 strcat(tbuf, "V34");
497                 count++;
498         }
499
500         return 0;
501 }
502
503 /*! \brief register a FAX technology module */
504 int ast_fax_tech_register(struct ast_fax_tech *tech)
505 {
506         struct fax_module *fax;
507
508         if (!(fax = ast_calloc(1, sizeof(*fax)))) {
509                 return -1;
510         }
511         fax->tech = tech;
512         AST_RWLIST_WRLOCK(&faxmodules);
513         AST_RWLIST_INSERT_TAIL(&faxmodules, fax, list);
514         AST_RWLIST_UNLOCK(&faxmodules);
515         ast_module_ref(ast_module_info->self);
516
517         ast_verb(3, "Registered handler for '%s' (%s)\n", fax->tech->type, fax->tech->description);
518
519         return 0;
520 }
521
522 /*! \brief unregister a FAX technology module */
523 void ast_fax_tech_unregister(struct ast_fax_tech *tech)
524 {
525         struct fax_module *fax;
526
527         ast_verb(3, "Unregistering FAX module type '%s'\n", tech->type);
528
529         AST_RWLIST_WRLOCK(&faxmodules);
530         AST_RWLIST_TRAVERSE_SAFE_BEGIN(&faxmodules, fax, list) {
531                 if (fax->tech != tech) {
532                         continue;
533                 }
534                 AST_RWLIST_REMOVE_CURRENT(list);
535                 ast_module_unref(ast_module_info->self);
536                 ast_free(fax);
537                 ast_verb(4, "Unregistered FAX module type '%s'\n", tech->type);
538                 break;  
539         }
540         AST_RWLIST_TRAVERSE_SAFE_END;
541         AST_RWLIST_UNLOCK(&faxmodules);
542 }
543
544 /*! \brief convert a ast_fax_state to a string */
545 const char *ast_fax_state_to_str(enum ast_fax_state state)
546 {
547         switch (state) {
548         case AST_FAX_STATE_UNINITIALIZED:
549                 return "Uninitialized";
550         case AST_FAX_STATE_INITIALIZED:
551                 return "Initialized";
552         case AST_FAX_STATE_OPEN:
553                 return "Open";
554         case AST_FAX_STATE_ACTIVE:
555                 return "Active";
556         case AST_FAX_STATE_COMPLETE:
557                 return "Complete";
558         default:
559                 ast_log(LOG_WARNING, "unhandled FAX state: %d\n", state);
560                 return "Unknown";
561         }
562 }
563
564 void ast_fax_log(int level, const char *file, const int line, const char *function, const char *msg)
565 {
566         if (fax_logger_level != -1) {
567                 ast_log_dynamic_level(fax_logger_level, "%s", msg);
568         } else {
569                 ast_log(level, file, line, function, "%s", msg);
570         }
571 }
572
573 /*! \brief convert a rate string to a rate */
574 static unsigned int fax_rate_str_to_int(const char *ratestr)
575 {
576         int rate;
577
578         if (sscanf(ratestr, "%d", &rate) != 1) {
579                 ast_log(LOG_ERROR, "failed to sscanf '%s' to rate\n", ratestr);
580                 return 0;
581         }
582         switch (rate) {
583         case 2400:
584         case 4800:
585         case 7200:
586         case 9600:
587         case 12000:
588         case 14400:
589         case 28800:
590         case 33600:
591                 return rate;
592         default:
593                 ast_log(LOG_WARNING, "ignoring invalid rate '%s'.  Valid options are {2400 | 4800 | 7200 | 9600 | 12000 | 14400 | 28800 | 33600}\n", ratestr);
594                 return 0;
595         }
596 }
597
598 /*! \brief destroy a FAX session structure */
599 static void destroy_session(void *session)
600 {
601         struct ast_fax_session *s = session;
602
603         if (s->tech) {
604                 if (s->tech_pvt) {
605                         s->tech->destroy_session(s);
606                 }
607                 ast_module_unref(s->tech->module);
608         }
609
610         if (s->details) {
611                 ao2_ref(s->details, -1);
612         }
613         
614         if (s->debug_info) {
615                 ast_dsp_free(s->debug_info->dsp);
616                 ast_free(s->debug_info);
617         }
618
619         if (s->smoother) {
620                 ast_smoother_free(s->smoother);
621         }
622
623         ast_atomic_fetchadd_int(&faxregistry.active_sessions, -1);
624
625         ast_free(s->channame);
626         ast_free(s->chan_uniqueid);
627 }
628
629 /*! \brief create a FAX session */
630 static struct ast_fax_session *fax_session_new(struct ast_fax_session_details *details, struct ast_channel *chan)
631 {
632         struct ast_fax_session *s;
633         struct fax_module *faxmod;
634
635         if (!(s = ao2_alloc(sizeof(*s), destroy_session))) {
636                 return NULL;
637         }
638
639         ast_atomic_fetchadd_int(&faxregistry.active_sessions, 1);
640
641         if (details->option.debug && (details->caps & AST_FAX_TECH_AUDIO)) {
642                 if (!(s->debug_info = ast_calloc(1, sizeof(*(s->debug_info))))) {
643                         ao2_ref(s, -1);
644                         return NULL;
645                 }
646                 if (!(s->debug_info->dsp = ast_dsp_new())) {
647                         ast_free(s->debug_info);
648                         s->debug_info = NULL;
649                         ao2_ref(s, -1);
650                         return NULL;
651                 }
652                 ast_dsp_set_threshold(s->debug_info->dsp, 128);
653         }       
654
655         if (!(s->channame = ast_strdup(chan->name))) {
656                 ao2_ref(s, -1);
657                 return NULL;
658         }
659
660         if (!(s->chan_uniqueid = ast_strdup(chan->uniqueid))) {
661                 ao2_ref(s, -1);
662                 return NULL;
663         }
664
665         s->chan = chan;
666         s->details = details;
667         ao2_ref(s->details, 1);
668         s->state = AST_FAX_STATE_UNINITIALIZED;
669
670         details->id = s->id = ast_atomic_fetchadd_int(&faxregistry.nextsessionname, 1);
671
672         /* locate a FAX technology module that can handle said requirements */
673         AST_RWLIST_RDLOCK(&faxmodules);
674         AST_RWLIST_TRAVERSE(&faxmodules, faxmod, list) {
675                 if ((faxmod->tech->caps & details->caps) != details->caps) {
676                         continue;
677                 }
678                 ast_debug(4, "Requesting a new FAX session from '%s'.\n", faxmod->tech->description);
679                 ast_module_ref(faxmod->tech->module);
680                 s->tech = faxmod->tech;
681                 break;
682         }
683         AST_RWLIST_UNLOCK(&faxmodules);
684
685         if (!faxmod) {
686                 ast_log(LOG_ERROR, "Could not locate a FAX technology module with capabilities (0x%X)\n", details->caps);
687                 ao2_ref(s, -1);
688                 return NULL;
689         }
690         if (!(s->tech_pvt = s->tech->new_session(s, NULL))) {
691                 ast_log(LOG_ERROR, "FAX session failed to initialize.\n");
692                 ao2_ref(s, -1);
693                 ast_module_unref(faxmod->tech->module);
694                 return NULL;
695         }
696         /* link the session to the session container */
697         if (!(ao2_link(faxregistry.container, s))) {
698                 ast_log(LOG_ERROR, "failed to add FAX session '%d' to container.\n", s->id);
699                 ao2_ref(s, -1);
700                 ast_module_unref(faxmod->tech->module);
701                 return NULL;
702         }
703         ast_debug(4, "channel '%s' using FAX session '%d'\n", s->channame, s->id);
704
705         return s;
706 }
707
708 static void get_manager_event_info(struct ast_channel *chan, struct manager_event_info *info)
709 {
710         pbx_substitute_variables_helper(chan, "${CONTEXT}", info->context, sizeof(info->context));
711         pbx_substitute_variables_helper(chan, "${EXTEN}", info->exten, sizeof(info->exten));
712         pbx_substitute_variables_helper(chan, "${CALLERID(num)}", info->cid, sizeof(info->cid));
713 }
714
715
716 /* \brief Generate a string of filenames using the given prefix and separator.
717  * \param details the fax session details
718  * \param prefix the prefix to each filename
719  * \param separator the separator between filenames
720  *
721  * This function generates a string of filenames from the given details
722  * structure and using the given prefix and separator.
723  *
724  * \retval NULL there was an error generating the string
725  * \return the string generated string
726  */
727 static char *generate_filenames_string(struct ast_fax_session_details *details, char *prefix, char *separator)
728 {
729         char *filenames, *c;
730         size_t size = 0;
731         int first = 1;
732         struct ast_fax_document *doc;
733
734         /* don't process empty lists */
735         if (AST_LIST_EMPTY(&details->documents)) {
736                 return NULL;
737         }
738
739         /* Calculate the total length of all of the file names */
740         AST_LIST_TRAVERSE(&details->documents, doc, next) {
741                 size += strlen(separator) + strlen(prefix) + strlen(doc->filename);
742         }
743         size += 1; /* add space for the terminating null */
744
745         if (!(filenames = ast_malloc(size))) {
746                 return NULL;
747         }
748         c = filenames;
749
750         ast_build_string(&c, &size, "%s%s", prefix, AST_LIST_FIRST(&details->documents)->filename);
751         AST_LIST_TRAVERSE(&details->documents, doc, next) {
752                 if (first) {
753                         first = 0;
754                         continue;
755                 }
756
757                 ast_build_string(&c, &size, "%s%s%s", separator, prefix, doc->filename);
758         }
759
760         return filenames;
761 }
762
763 /*! \brief send a FAX status manager event */
764 static int report_fax_status(struct ast_channel *chan, struct ast_fax_session_details *details, const char *status)
765 {
766         char *filenames = generate_filenames_string(details, "FileName: ", "\r\n");
767         if (!filenames) {
768                 return 1;
769         }
770
771         ast_channel_lock(chan);
772         pbx_builtin_setvar_helper(chan, "FAXSTATUSSTRING", status);
773         if (details->option.statusevents) {
774                 struct manager_event_info info;
775
776                 get_manager_event_info(chan, &info);
777                 manager_event(EVENT_FLAG_CALL,
778                               (details->caps & AST_FAX_TECH_RECEIVE) ? "ReceiveFAXStatus" : "SendFAXStatus",
779                               "Status: %s\r\n"
780                               "Channel: %s\r\n"
781                               "Context: %s\r\n"
782                               "Exten: %s\r\n"
783                               "CallerID: %s\r\n"
784                               "LocalStationID: %s\r\n"
785                               "%s\r\n",
786                               status,
787                               chan->name,
788                               info.context,
789                               info.exten,
790                               info.cid,
791                               details->localstationid,
792                               filenames);
793         }
794         ast_channel_unlock(chan);
795         ast_free(filenames);
796
797         return 0;
798 }
799
800 #define GENERIC_FAX_EXEC_ERROR(fax, chan, errorstr, reason)     \
801         do {    \
802                 ast_log(LOG_ERROR, "channel '%s' FAX session '%d' failure, reason: '%s' (%s)\n", chan->name, fax->id, reason, errorstr); \
803                 pbx_builtin_setvar_helper(chan, "FAXSTATUSSTRING", reason); \
804                 if (ast_strlen_zero(fax->details->result)) ast_string_field_set(fax->details, result, "FAILED"); \
805                 if (ast_strlen_zero(fax->details->resultstr)) ast_string_field_set(fax->details, resultstr, reason); \
806                 if (ast_strlen_zero(fax->details->error)) ast_string_field_set(fax->details, error, errorstr); \
807                 res = ms = -1; \
808         } while (0)
809
810 static void t38_parameters_ast_to_fax(struct ast_fax_t38_parameters *dst, const struct ast_control_t38_parameters *src)
811 {
812         dst->version = src->version;
813         dst->max_ifp = src->max_ifp;
814         dst->rate = src->rate;
815         dst->rate_management = src->rate_management;
816         dst->fill_bit_removal = src->fill_bit_removal;
817         dst->transcoding_mmr = src->transcoding_mmr;
818         dst->transcoding_jbig = src->transcoding_jbig;
819 }
820
821 static void t38_parameters_fax_to_ast(struct ast_control_t38_parameters *dst, const struct ast_fax_t38_parameters *src)
822 {
823         dst->version = src->version;
824         dst->max_ifp = src->max_ifp;
825         dst->rate = src->rate;
826         dst->rate_management = src->rate_management;
827         dst->fill_bit_removal = src->fill_bit_removal;
828         dst->transcoding_mmr = src->transcoding_mmr;
829         dst->transcoding_jbig = src->transcoding_jbig;
830 }
831
832 static int set_fax_t38_caps(struct ast_channel *chan, struct ast_fax_session_details *details)
833 {
834         switch (ast_channel_get_t38_state(chan)) {
835         case T38_STATE_UNKNOWN:
836                 details->caps |= AST_FAX_TECH_T38;
837                 break;
838         case T38_STATE_UNAVAILABLE:
839                 details->caps |= AST_FAX_TECH_AUDIO;
840                 break;
841         case T38_STATE_NEGOTIATING: {
842                 /* the other end already sent us a T.38 reinvite, so we need to prod the channel
843                  * driver into resending their parameters to us if it supports doing so... if
844                  * not, we can't proceed, because we can't create a proper reply without them.
845                  * if it does work, the channel driver will send an AST_CONTROL_T38_PARAMETERS
846                  * with a request of AST_T38_REQUEST_NEGOTIATE, which will be read by the function
847                  * that gets called after this one completes
848                  */
849                 struct ast_control_t38_parameters parameters = { .request_response = AST_T38_REQUEST_PARMS, };
850                 if (ast_indicate_data(chan, AST_CONTROL_T38_PARAMETERS, &parameters, sizeof(parameters)) != AST_T38_REQUEST_PARMS) {
851                         ast_log(LOG_ERROR, "channel '%s' is in an unsupported T.38 negotiation state, cannot continue.\n", chan->name);
852                         return -1;
853                 }
854                 details->caps |= AST_FAX_TECH_T38;
855                 break;
856         }
857         default:
858                 ast_log(LOG_ERROR, "channel '%s' is in an unsupported T.38 negotiation state, cannot continue.\n", chan->name);
859                 return -1;
860         }
861
862         return 0;
863 }
864
865 static int disable_t38(struct ast_channel *chan)
866 {
867         int ms;
868         struct ast_frame *frame = NULL;
869         struct ast_control_t38_parameters t38_parameters = { .request_response = AST_T38_REQUEST_TERMINATE, };
870
871         ast_debug(1, "Shutting down T.38 on %s\n", chan->name);
872         if (ast_indicate_data(chan, AST_CONTROL_T38_PARAMETERS, &t38_parameters, sizeof(t38_parameters)) != 0) {
873                 ast_log(LOG_WARNING, "error while disabling T.38 on channel '%s'\n", chan->name);
874                 return -1;
875         }
876
877         /* wait up to five seconds for negotiation to complete */
878         ms = 5000;
879
880         while (ms > 0) {
881                 ms = ast_waitfor(chan, ms);
882                 if (ms < 0) {
883                         ast_log(LOG_WARNING, "error while disabling T.38 on channel '%s'\n", chan->name);
884                         return -1;
885                 }
886
887                 if (ms == 0) { /* all done, nothing happened */
888                         ast_log(LOG_WARNING, "channel '%s' timed-out during T.38 shutdown\n", chan->name);
889                         break;
890                 }
891
892                 if (!(frame = ast_read(chan))) {
893                         return -1;
894                 }
895                 if ((frame->frametype == AST_FRAME_CONTROL) &&
896                     (frame->subclass.integer == AST_CONTROL_T38_PARAMETERS) &&
897                     (frame->datalen == sizeof(t38_parameters))) {
898                         struct ast_control_t38_parameters *parameters = frame->data.ptr;
899
900                         switch (parameters->request_response) {
901                         case AST_T38_TERMINATED:
902                                 ast_debug(1, "Shut down T.38 on %s\n", chan->name);
903                                 break;
904                         case AST_T38_REFUSED:
905                                 ast_log(LOG_WARNING, "channel '%s' refused to disable T.38\n", chan->name);
906                                 ast_frfree(frame);
907                                 return -1;
908                         default:
909                                 ast_log(LOG_ERROR, "channel '%s' failed to disable T.38\n", chan->name);
910                                 ast_frfree(frame);
911                                 return -1;
912                         }
913                         ast_frfree(frame);
914                         break;
915                 }
916                 ast_frfree(frame);
917         }
918
919         return 0;
920 }
921
922 static struct ast_control_t38_parameters our_t38_parameters = {
923         .version = 0,
924         .max_ifp = 400,
925         .rate = AST_T38_RATE_14400,
926         .rate_management = AST_T38_RATE_MANAGEMENT_TRANSFERRED_TCF,
927 };
928
929 /*! \brief this is the generic FAX session handling function */
930 static int generic_fax_exec(struct ast_channel *chan, struct ast_fax_session_details *details)
931 {
932         int ms;
933         int timeout = RES_FAX_TIMEOUT;
934         int res = 0, chancount;
935         unsigned int expected_frametype = -1;
936         union ast_frame_subclass expected_framesubclass = { .integer = -1 };
937         char tbuf[10];
938         unsigned int t38negotiated = (ast_channel_get_t38_state(chan) == T38_STATE_NEGOTIATED);
939         struct ast_control_t38_parameters t38_parameters;
940         const char *tempvar;
941         struct ast_fax_session *fax = NULL;
942         struct ast_frame *frame = NULL;
943         struct ast_channel *c = chan;
944         unsigned int orig_write_format = 0, orig_read_format = 0;
945
946         chancount = 1;
947
948         /* create the FAX session */
949         if (!(fax = fax_session_new(details, chan))) {
950                 ast_log(LOG_ERROR, "Can't create a FAX session, FAX attempt failed.\n");
951                 report_fax_status(chan, details, "No Available Resource");
952                 return -1;
953         }
954
955         ast_channel_lock(chan);
956         /* update session details */    
957         if (ast_strlen_zero(details->headerinfo) && (tempvar = pbx_builtin_getvar_helper(chan, "LOCALHEADERINFO"))) {
958                 ast_string_field_set(details, headerinfo, tempvar);
959         }
960         if (ast_strlen_zero(details->localstationid)) {
961                 tempvar = pbx_builtin_getvar_helper(chan, "LOCALSTATIONID");
962                 ast_string_field_set(details, localstationid, tempvar ? tempvar : "unknown");
963         }
964         ast_channel_unlock(chan);
965
966         report_fax_status(chan, details, "Allocating Resources");
967
968         if (details->caps & AST_FAX_TECH_AUDIO) {
969                 expected_frametype = AST_FRAME_VOICE;;
970                 expected_framesubclass.codec = AST_FORMAT_SLINEAR;
971                 orig_write_format = chan->writeformat;
972                 if (ast_set_write_format(chan, AST_FORMAT_SLINEAR) < 0) {
973                         ast_log(LOG_ERROR, "channel '%s' failed to set write format to signed linear'.\n", chan->name);
974                         ao2_lock(faxregistry.container);
975                         ao2_unlink(faxregistry.container, fax);
976                         ao2_unlock(faxregistry.container);
977                         ao2_ref(fax, -1);
978                         ast_channel_unlock(chan);
979                         return -1;
980                 }
981                 orig_read_format = chan->readformat;
982                 if (ast_set_read_format(chan, AST_FORMAT_SLINEAR) < 0) {
983                         ast_log(LOG_ERROR, "channel '%s' failed to set read format to signed linear.\n", chan->name);
984                         ao2_lock(faxregistry.container);
985                         ao2_unlink(faxregistry.container, fax);
986                         ao2_unlock(faxregistry.container);
987                         ao2_ref(fax, -1);
988                         ast_channel_unlock(chan);
989                         return -1;
990                 }
991                 if (fax->smoother) {
992                         ast_smoother_free(fax->smoother);
993                         fax->smoother = NULL;
994                 }
995                 if (!(fax->smoother = ast_smoother_new(320))) {
996                         ast_log(LOG_WARNING, "Channel '%s' FAX session '%d' failed to obtain a smoother.\n", chan->name, fax->id);
997                 }
998         } else {
999                 expected_frametype = AST_FRAME_MODEM;
1000                 expected_framesubclass.codec = AST_MODEM_T38;
1001         }
1002
1003         if (fax->debug_info) {
1004                 fax->debug_info->base_tv = ast_tvnow();
1005         }
1006
1007         /* reset our result fields just in case the fax tech driver wants to
1008          * set custom error messages */
1009         ast_string_field_set(details, result, "");
1010         ast_string_field_set(details, resultstr, "");
1011         ast_string_field_set(details, error, "");
1012
1013         if (fax->tech->start_session(fax) < 0) {
1014                 GENERIC_FAX_EXEC_ERROR(fax, chan, "INIT_ERROR", "failed to start FAX session");
1015         }
1016
1017         pbx_builtin_setvar_helper(chan, "FAXSTATUS", NULL);
1018         pbx_builtin_setvar_helper(chan, "FAXERROR", NULL);
1019         report_fax_status(chan, details, "FAX Transmission In Progress");
1020
1021         ast_debug(5, "channel %s will wait on FAX fd %d\n", chan->name, fax->fd);
1022
1023         /* handle frames for the session */
1024         ms = 1000;
1025         while ((res > -1) && (ms > -1) && (timeout > 0)) {
1026                 struct ast_channel *ready_chan;
1027                 int ofd, exception;
1028
1029                 ms = 1000;
1030                 errno = 0;
1031                 ready_chan = ast_waitfor_nandfds(&c, chancount, &fax->fd, 1, &exception, &ofd, &ms);
1032                 if (ready_chan) {
1033                         if (!(frame = ast_read(chan))) {
1034                                 /* the channel is probably gone, so lets stop polling on it and let the
1035                                  * FAX session complete before we exit the application.  if needed,
1036                                  * send the FAX stack silence so the modems can finish their session without
1037                                  * any problems */
1038                                 ast_log(LOG_NOTICE, "Channel '%s' did not return a frame; probably hung up.\n", chan->name);
1039                                 c = NULL;
1040                                 chancount = 0;
1041                                 timeout -= (1000 - ms);
1042                                 fax->tech->cancel_session(fax);
1043                                 if (fax->tech->generate_silence) {
1044                                         fax->tech->generate_silence(fax);
1045                                 }
1046                                 continue;
1047                         }
1048
1049                         if ((frame->frametype == AST_FRAME_CONTROL) &&
1050                             (frame->subclass.integer == AST_CONTROL_T38_PARAMETERS) &&
1051                             (frame->datalen == sizeof(t38_parameters))) {
1052                                 unsigned int was_t38 = t38negotiated;
1053                                 struct ast_control_t38_parameters *parameters = frame->data.ptr;
1054                                 
1055                                 switch (parameters->request_response) {
1056                                 case AST_T38_REQUEST_NEGOTIATE:
1057                                         /* the other end has requested a switch to T.38, so reply that we are willing, if we can
1058                                          * do T.38 as well
1059                                          */
1060                                         t38_parameters_fax_to_ast(&t38_parameters, &details->our_t38_parameters);
1061                                         t38_parameters.request_response = (details->caps & AST_FAX_TECH_T38) ? AST_T38_NEGOTIATED : AST_T38_REFUSED;
1062                                         ast_indicate_data(chan, AST_CONTROL_T38_PARAMETERS, &t38_parameters, sizeof(t38_parameters));
1063                                         break;
1064                                 case AST_T38_NEGOTIATED:
1065                                         t38_parameters_ast_to_fax(&details->their_t38_parameters, parameters);
1066                                         t38negotiated = 1;
1067                                         break;
1068                                 default:
1069                                         break;
1070                                 }
1071                                 if (t38negotiated && !was_t38) {
1072                                         fax->tech->switch_to_t38(fax);
1073                                         details->caps &= ~AST_FAX_TECH_AUDIO;
1074                                         expected_frametype = AST_FRAME_MODEM;
1075                                         expected_framesubclass.codec = AST_MODEM_T38;
1076                                         if (fax->smoother) {
1077                                                 ast_smoother_free(fax->smoother);
1078                                                 fax->smoother = NULL;
1079                                         }
1080                                         
1081                                         report_fax_status(chan, details, "T.38 Negotiated");
1082                                         
1083                                         ast_verb(3, "Channel '%s' switched to T.38 FAX session '%d'.\n", chan->name, fax->id);
1084                                 }
1085                         } else if ((frame->frametype == expected_frametype) &&
1086                                    (!memcmp(&frame->subclass, &expected_framesubclass, sizeof(frame->subclass)))) {
1087                                 struct ast_frame *f;
1088                                 
1089                                 if (fax->smoother) {
1090                                         /* push the frame into a smoother */
1091                                         if (ast_smoother_feed(fax->smoother, frame) < 0) {
1092                                                 GENERIC_FAX_EXEC_ERROR(fax, chan, "UNKNOWN", "Failed to feed the smoother");
1093                                         }
1094                                         while ((f = ast_smoother_read(fax->smoother)) && (f->data.ptr)) {
1095                                                 if (fax->debug_info) {
1096                                                         debug_check_frame_for_silence(fax, 1, f);
1097                                                 }
1098                                                 /* write the frame to the FAX stack */
1099                                                 fax->tech->write(fax, f);
1100                                                 fax->frames_received++;
1101                                                 if (f != frame) {
1102                                                         ast_frfree(f);
1103                                                 }
1104                                         }
1105                                 } else {
1106                                         /* write the frame to the FAX stack */
1107                                         fax->tech->write(fax, frame);
1108                                         fax->frames_received++;
1109                                 }
1110                                 timeout = RES_FAX_TIMEOUT;
1111                         }
1112                         ast_frfree(frame);
1113                 } else if (ofd == fax->fd) {
1114                         /* read a frame from the FAX stack and send it out the channel.
1115                          * the FAX stack will return a NULL if the FAX session has already completed */
1116                         if (!(frame = fax->tech->read(fax))) {
1117                                 break;
1118                         }
1119
1120                         if (fax->debug_info && (frame->frametype == AST_FRAME_VOICE)) {
1121                                 debug_check_frame_for_silence(fax, 0, frame);
1122                         }
1123
1124                         ast_write(chan, frame);
1125                         fax->frames_sent++;
1126                         ast_frfree(frame);
1127                         timeout = RES_FAX_TIMEOUT;
1128                 } else {
1129                         if (ms && (ofd < 0)) {
1130                                 if ((errno == 0) || (errno == EINTR)) {
1131                                         timeout -= (1000 - ms);
1132                                         continue;
1133                                 } else {
1134                                         ast_log(LOG_WARNING, "something bad happened while channel '%s' was polling.\n", chan->name);
1135                                         res = ms;
1136                                         break;
1137                                 }
1138                         } else {
1139                                 /* nothing happened */
1140                                 if (timeout > 0) {
1141                                         timeout -= 1000;
1142                                         continue;
1143                                 } else {
1144                                         ast_log(LOG_WARNING, "channel '%s' timed-out during the FAX transmission.\n", chan->name);
1145                                         GENERIC_FAX_EXEC_ERROR(fax, chan, "TIMEOUT", "fax session timed-out");
1146                                         break;
1147                                 }
1148                         }
1149                 }
1150         }
1151         ast_debug(3, "channel '%s' - event loop stopped { timeout: %d, ms: %d, res: %d }\n", chan->name, timeout, ms, res);
1152
1153         pbx_builtin_setvar_helper(chan, "FAXSTATUS", details->result);
1154         pbx_builtin_setvar_helper(chan, "FAXERROR", details->error);
1155         pbx_builtin_setvar_helper(chan, "FAXSTATUSSTRING", details->resultstr);
1156         pbx_builtin_setvar_helper(chan, "REMOTESTATIONID", details->remotestationid);
1157         pbx_builtin_setvar_helper(chan, "FAXBITRATE", details->transfer_rate);
1158         pbx_builtin_setvar_helper(chan, "FAXRESOLUTION", details->resolution);
1159
1160         snprintf(tbuf, sizeof(tbuf), "%d", details->pages_transferred);
1161         pbx_builtin_setvar_helper(chan, "FAXPAGES", tbuf);
1162
1163         ast_atomic_fetchadd_int(&faxregistry.fax_complete, 1);
1164         if (!strcasecmp(details->result, "FAILED")) {
1165                 ast_atomic_fetchadd_int(&faxregistry.fax_failures, 1);
1166         }
1167
1168         if (fax) {
1169                 ao2_lock(faxregistry.container);
1170                 ao2_unlink(faxregistry.container, fax);
1171                 ao2_unlock(faxregistry.container);
1172                 ao2_ref(fax, -1);
1173         }
1174
1175         /* if the channel is still alive, and we changed its read/write formats,
1176          * restore them now
1177          */
1178         if (chancount) {
1179                 if (orig_read_format) {
1180                         ast_set_read_format(chan, orig_read_format);
1181                 }
1182                 if (orig_write_format) {
1183                         ast_set_write_format(chan, orig_write_format);
1184                 }
1185         }
1186
1187         /* return the chancount so the calling function can determine if the channel hungup during this FAX session or not */
1188         return chancount;
1189 }
1190
1191 static int receivefax_t38_init(struct ast_channel *chan, struct ast_fax_session_details *details)
1192 {
1193         int ms;
1194         struct ast_frame *frame = NULL;
1195         struct ast_control_t38_parameters t38_parameters;
1196
1197         t38_parameters_ast_to_fax(&details->our_t38_parameters, &our_t38_parameters);
1198
1199         /* don't send any audio if we've already received a T.38 reinvite */
1200         if (ast_channel_get_t38_state(chan) != T38_STATE_NEGOTIATING) {
1201                 /* generate 3 seconds of CED */
1202                 if (ast_playtones_start(chan, 1024, "!2100/3000", 1)) {
1203                         ast_log(LOG_ERROR, "error generating CED tone on %s\n", chan->name);
1204                         return -1;
1205                 }
1206
1207                 ms = 3000;
1208                 while (ms > 0) {
1209                         ms = ast_waitfor(chan, ms);
1210                         if (ms < 0) {
1211                                 ast_log(LOG_ERROR, "error while generating CED tone on %s\n", chan->name);
1212                                 ast_playtones_stop(chan);
1213                                 return -1;
1214                         }
1215
1216                         if (ms == 0) { /* all done, nothing happened */
1217                                 break;
1218                         }
1219
1220                         if (!(frame = ast_read(chan))) {
1221                                 ast_log(LOG_ERROR, "error reading frame while generating CED tone on %s\n", chan->name);
1222                                 ast_playtones_stop(chan);
1223                                 return -1;
1224                         }
1225
1226                         if ((frame->frametype == AST_FRAME_CONTROL) &&
1227                             (frame->subclass.integer == AST_CONTROL_T38_PARAMETERS) &&
1228                             (frame->datalen == sizeof(t38_parameters))) {
1229                                 struct ast_control_t38_parameters *parameters = frame->data.ptr;
1230
1231                                 switch (parameters->request_response) {
1232                                 case AST_T38_REQUEST_NEGOTIATE:
1233                                         /* the other end has requested a switch to T.38, so reply that we are willing, if we can
1234                                          * do T.38 as well
1235                                          */
1236                                         t38_parameters_fax_to_ast(&t38_parameters, &details->our_t38_parameters);
1237                                         t38_parameters.request_response = (details->caps & AST_FAX_TECH_T38) ? AST_T38_NEGOTIATED : AST_T38_REFUSED;
1238                                         ast_indicate_data(chan, AST_CONTROL_T38_PARAMETERS, &t38_parameters, sizeof(t38_parameters));
1239                                         ast_playtones_stop(chan);
1240                                         break;
1241                                 case AST_T38_NEGOTIATED:
1242                                         ast_log(LOG_NOTICE, "Negotiated T.38 for receive on %s\n", chan->name);
1243                                         t38_parameters_ast_to_fax(&details->their_t38_parameters, parameters);
1244                                         details->caps &= ~AST_FAX_TECH_AUDIO;
1245                                         report_fax_status(chan, details, "T.38 Negotiated");
1246                                         break;
1247                                 default:
1248                                         break;
1249                                 }
1250                         }
1251                         ast_frfree(frame);
1252                 }
1253
1254                 ast_playtones_stop(chan);
1255         }
1256
1257         /* if T.38 was negotiated, we are done initializing */
1258         if (ast_channel_get_t38_state(chan) == T38_STATE_NEGOTIATED) {
1259                 return 0;
1260         }
1261
1262         /* request T.38 */
1263         ast_log(LOG_NOTICE, "Negotiating T.38 for receive on %s\n", chan->name);
1264
1265         /* wait up to five seconds for negotiation to complete */
1266         ms = 5000;
1267
1268         /* set parameters based on the session's parameters */
1269         t38_parameters_fax_to_ast(&t38_parameters, &details->our_t38_parameters);
1270         t38_parameters.request_response = AST_T38_REQUEST_NEGOTIATE;
1271         if ((ast_indicate_data(chan, AST_CONTROL_T38_PARAMETERS, &t38_parameters, sizeof(t38_parameters)) != 0)) {
1272                 return -1;
1273         }
1274
1275         while (ms > 0) {
1276                 ms = ast_waitfor(chan, ms);
1277                 if (ms < 0) {
1278                         ast_log(LOG_WARNING, "error on '%s' while waiting for T.38 negotiation.\n", chan->name);
1279                         return -1;
1280                 }
1281
1282                 if (ms == 0) { /* all done, nothing happened */
1283                         ast_log(LOG_WARNING, "channel '%s' timed-out during the T.38 negotiation.\n", chan->name);
1284                         details->caps &= ~AST_FAX_TECH_T38;
1285                         break;
1286                 }
1287
1288                 if (!(frame = ast_read(chan))) {
1289                         ast_log(LOG_WARNING, "error on '%s' while waiting for T.38 negotiation.\n", chan->name);
1290                         return -1;
1291                 }
1292
1293                 if ((frame->frametype == AST_FRAME_CONTROL) &&
1294                                 (frame->subclass.integer == AST_CONTROL_T38_PARAMETERS) &&
1295                                 (frame->datalen == sizeof(t38_parameters))) {
1296                         struct ast_control_t38_parameters *parameters = frame->data.ptr;
1297
1298                         switch (parameters->request_response) {
1299                         case AST_T38_REQUEST_NEGOTIATE:
1300                                 t38_parameters_fax_to_ast(&t38_parameters, &details->our_t38_parameters);
1301                                 t38_parameters.request_response = AST_T38_NEGOTIATED;
1302                                 ast_indicate_data(chan, AST_CONTROL_T38_PARAMETERS, &t38_parameters, sizeof(t38_parameters));
1303                                 break;
1304                         case AST_T38_NEGOTIATED:
1305                                 ast_log(LOG_NOTICE, "Negotiated T.38 for receive on %s\n", chan->name);
1306                                 t38_parameters_ast_to_fax(&details->their_t38_parameters, parameters);
1307                                 details->caps &= ~AST_FAX_TECH_AUDIO;
1308                                 report_fax_status(chan, details, "T.38 Negotiated");
1309                                 ms = 0;
1310                                 break;
1311                         case AST_T38_REFUSED:
1312                                 ast_log(LOG_WARNING, "channel '%s' refused to negotiate T.38\n", chan->name);
1313                                 details->caps &= ~AST_FAX_TECH_T38;
1314                                 ms = 0;
1315                                 break;
1316                         default:
1317                                 ast_log(LOG_ERROR, "channel '%s' failed to negotiate T.38\n", chan->name);
1318                                 details->caps &= ~AST_FAX_TECH_T38;
1319                                 ms = 0;
1320                                 break;
1321                         }
1322                 }
1323                 ast_frfree(frame);
1324         }
1325
1326         /* if T.38 was negotiated, we are done initializing */
1327         if (ast_channel_get_t38_state(chan) == T38_STATE_NEGOTIATED) {
1328                 return 0;
1329         }
1330
1331         /* if we made it here, then T.38 failed, check the 'f' flag */
1332         if (details->option.allow_audio != AST_FAX_OPTFLAG_TRUE) {
1333                 ast_log(LOG_WARNING, "Audio FAX not allowed on channel '%s' and T.38 negotiation failed; aborting.\n", chan->name);
1334                 return -1;
1335         }
1336
1337         /* ok, audio fallback is allowed */
1338         details->caps |= AST_FAX_TECH_AUDIO;
1339
1340         return 0;
1341 }
1342
1343 /*! \brief initiate a receive FAX session */
1344 static int receivefax_exec(struct ast_channel *chan, const char *data)
1345 {
1346         char *parse;
1347         int channel_alive;
1348         struct ast_fax_session_details *details;
1349         struct ast_fax_document *doc;
1350         AST_DECLARE_APP_ARGS(args,
1351                 AST_APP_ARG(filename);
1352                 AST_APP_ARG(options);
1353         );
1354         struct ast_flags opts = { 0, };
1355         struct manager_event_info info;
1356
1357         /* Get a FAX session details structure from the channel's FAX datastore and create one if
1358          * it does not already exist. */
1359         if (!(details = find_or_create_details(chan))) {
1360                 ast_log(LOG_ERROR, "System cannot provide memory for session requirements.\n");
1361                 return -1;
1362         }
1363
1364
1365         if (ast_strlen_zero(data)) {
1366                 ast_string_field_set(details, error, "INVALID_ARGUMENTS");
1367                 ast_string_field_set(details, resultstr, "invalid arguments");
1368                 ast_log(LOG_WARNING, "%s requires an argument (filename[,options])\n", app_receivefax);
1369                 return -1;
1370         }
1371         parse = ast_strdupa(data);
1372         AST_STANDARD_APP_ARGS(args, parse);
1373         
1374         /* initialize output channel variables */
1375         pbx_builtin_setvar_helper(chan, "FAXSTATUS", "FAILED");
1376         pbx_builtin_setvar_helper(chan, "FAXERROR", "Application Problems");
1377         pbx_builtin_setvar_helper(chan, "FAXSTATUSSTRING", "Invalid application arguments.");
1378         pbx_builtin_setvar_helper(chan, "REMOTESTATIONID", NULL);
1379         pbx_builtin_setvar_helper(chan, "FAXPAGES", "0");
1380         pbx_builtin_setvar_helper(chan, "FAXBITRATE", NULL);
1381         pbx_builtin_setvar_helper(chan, "FAXRESOLUTION", NULL);
1382
1383         if (!ast_strlen_zero(args.options) &&
1384             ast_app_parse_options(fax_exec_options, &opts, NULL, args.options)) {
1385                 return -1;
1386         }
1387         if (ast_strlen_zero(args.filename)) {
1388                 ast_string_field_set(details, error, "INVALID_ARGUMENTS");
1389                 ast_string_field_set(details, resultstr, "invalid arguments");
1390                 ast_log(LOG_WARNING, "%s requires an argument (filename[,options])\n", app_receivefax);
1391                 return -1;
1392         }
1393
1394         /* check for unsupported FAX application options */
1395         if (ast_test_flag(&opts, OPT_CALLERMODE) || ast_test_flag(&opts, OPT_CALLEDMODE)) {
1396                 ast_string_field_set(details, error, "INVALID_ARGUMENTS");
1397                 ast_string_field_set(details, resultstr, "invalid arguments");
1398                 ast_log(LOG_WARNING, "%s does not support polling\n", app_receivefax);
1399                 return -1;
1400         }
1401         
1402         /* make sure the channel is up */
1403         if (chan->_state != AST_STATE_UP) {
1404                 if (ast_answer(chan)) {
1405                         ast_log(LOG_WARNING, "Channel '%s' failed answer attempt.\n", chan->name);
1406                         return -1;
1407                 }
1408         }
1409
1410         ast_atomic_fetchadd_int(&faxregistry.fax_rx_attempts, 1);
1411
1412         pbx_builtin_setvar_helper(chan, "FAXERROR", "Channel Problems");
1413         pbx_builtin_setvar_helper(chan, "FAXSTATUSSTRING", "Error before FAX transmission started.");
1414
1415         if (!(doc = ast_calloc(1, sizeof(*doc) + strlen(args.filename) + 1))) {
1416                 ast_string_field_set(details, error, "MEMORY_ERROR");
1417                 ast_string_field_set(details, resultstr, "error allocating memory");
1418                 ast_log(LOG_ERROR, "System cannot provide memory for session requirements.\n");
1419                 ao2_ref(details, -1);
1420                 return -1;
1421         }
1422
1423         strcpy(doc->filename, args.filename);
1424         AST_LIST_INSERT_TAIL(&details->documents, doc, next);
1425
1426         ast_verb(3, "Channel '%s' receiving FAX '%s'\n", chan->name, args.filename);
1427
1428         details->caps = AST_FAX_TECH_RECEIVE;
1429
1430         /* check for debug */
1431         if (ast_test_flag(&opts, OPT_DEBUG) || global_fax_debug) {
1432                 details->option.debug = AST_FAX_OPTFLAG_TRUE;
1433         }
1434
1435         /* check for request for status events */
1436         if (ast_test_flag(&opts, OPT_STATUS)) {
1437                 details->option.statusevents = AST_FAX_OPTFLAG_TRUE;
1438         }
1439
1440         if ((ast_channel_get_t38_state(chan) == T38_STATE_UNAVAILABLE) ||
1441             ast_test_flag(&opts, OPT_ALLOWAUDIO)) {
1442                 details->option.allow_audio = AST_FAX_OPTFLAG_TRUE;
1443         }
1444
1445         if (set_fax_t38_caps(chan, details)) {
1446                 ast_string_field_set(details, error, "T38_NEG_ERROR");
1447                 ast_string_field_set(details, resultstr, "error negotiating T.38");
1448                 ao2_ref(details, -1);
1449                 return -1;
1450         }
1451
1452         if (details->caps & AST_FAX_TECH_T38) {
1453                 if (receivefax_t38_init(chan, details)) {
1454                         ast_string_field_set(details, error, "T38_NEG_ERROR");
1455                         ast_string_field_set(details, resultstr, "error negotiating T.38");
1456                         ao2_ref(details, -1);
1457                         ast_log(LOG_ERROR, "error initializing channel '%s' in T.38 mode\n", chan->name);
1458                         return -1;
1459                 }
1460         } else {
1461                 details->option.send_ced = 1;
1462         }
1463
1464         if ((channel_alive = generic_fax_exec(chan, details)) < 0) {
1465                 ast_atomic_fetchadd_int(&faxregistry.fax_failures, 1);
1466         }
1467
1468         if (ast_channel_get_t38_state(chan) == T38_STATE_NEGOTIATED) {
1469                 if (disable_t38(chan)) {
1470                         ast_log(LOG_WARNING, "error disabling T.38 mode on %s\n", chan->name);
1471                 }
1472         }
1473
1474         /* send out the AMI completion event */
1475         ast_channel_lock(chan);
1476
1477         get_manager_event_info(chan, &info);
1478         manager_event(EVENT_FLAG_CALL,
1479                       "ReceiveFAX", 
1480                       "Channel: %s\r\n"
1481                       "Context: %s\r\n"
1482                       "Exten: %s\r\n"
1483                       "CallerID: %s\r\n"
1484                       "RemoteStationID: %s\r\n"
1485                       "LocalStationID: %s\r\n"
1486                       "PagesTransferred: %s\r\n"
1487                       "Resolution: %s\r\n"
1488                       "TransferRate: %s\r\n"
1489                       "FileName: %s\r\n",
1490                       chan->name,
1491                       info.context,
1492                       info.exten,
1493                       info.cid,
1494                       pbx_builtin_getvar_helper(chan, "REMOTESTATIONID"),
1495                       pbx_builtin_getvar_helper(chan, "LOCALSTATIONID"),
1496                       pbx_builtin_getvar_helper(chan, "FAXPAGES"),
1497                       pbx_builtin_getvar_helper(chan, "FAXRESOLUTION"),
1498                       pbx_builtin_getvar_helper(chan, "FAXBITRATE"),
1499                       args.filename);
1500         ast_channel_unlock(chan);
1501
1502         ao2_ref(details, -1);
1503
1504         /* If the channel hungup return -1; otherwise, return 0 to continue in the dialplan */
1505         return (!channel_alive) ? -1 : 0;
1506 }
1507
1508 static int sendfax_t38_init(struct ast_channel *chan, struct ast_fax_session_details *details)
1509 {
1510         int ms;
1511         struct ast_frame *frame = NULL;
1512         struct ast_control_t38_parameters t38_parameters;
1513
1514         t38_parameters_ast_to_fax(&details->our_t38_parameters, &our_t38_parameters);
1515
1516         /* send CNG tone while listening for the receiver to initiate a switch
1517          * to T.38 mode; if they do, stop sending the CNG tone and proceed with
1518          * the switch.
1519          *
1520          * 10500 is enough time for 3 CNG tones
1521          */
1522         ms = 10500;
1523
1524         /* don't send any audio if we've already received a T.38 reinvite */
1525         if (ast_channel_get_t38_state(chan) != T38_STATE_NEGOTIATING) {
1526                 if (ast_playtones_start(chan, 1024, "!1100/500,!0/3000,!1100/500,!0/3000,!1100/500,!0/3000", 1)) {
1527                         ast_log(LOG_ERROR, "error generating CNG tone on %s\n", chan->name);
1528                         return -1;
1529                 }
1530         }
1531
1532         while (ms > 0) {
1533                 ms = ast_waitfor(chan, ms);
1534                 if (ms < 0) {
1535                         ast_log(LOG_ERROR, "error while generating CNG tone on %s\n", chan->name);
1536                         ast_playtones_stop(chan);
1537                         return -1;
1538                 }
1539
1540                 if (ms == 0) { /* all done, nothing happened */
1541                         break;
1542                 }
1543
1544                 if (!(frame = ast_read(chan))) {
1545                         ast_log(LOG_ERROR, "error reading frame while generating CNG tone on %s\n", chan->name);
1546                         ast_playtones_stop(chan);
1547                         return -1;
1548                 }
1549
1550                 if ((frame->frametype == AST_FRAME_CONTROL) &&
1551                                 (frame->subclass.integer == AST_CONTROL_T38_PARAMETERS) &&
1552                                 (frame->datalen == sizeof(t38_parameters))) {
1553                         struct ast_control_t38_parameters *parameters = frame->data.ptr;
1554
1555                         switch (parameters->request_response) {
1556                         case AST_T38_REQUEST_NEGOTIATE:
1557                                 /* the other end has requested a switch to T.38, so reply that we are willing, if we can
1558                                  * do T.38 as well
1559                                  */
1560                                 t38_parameters_fax_to_ast(&t38_parameters, &details->our_t38_parameters);
1561                                 t38_parameters.request_response = (details->caps & AST_FAX_TECH_T38) ? AST_T38_NEGOTIATED : AST_T38_REFUSED;
1562                                 ast_indicate_data(chan, AST_CONTROL_T38_PARAMETERS, &t38_parameters, sizeof(t38_parameters));
1563                                 ast_playtones_stop(chan);
1564                                 break;
1565                         case AST_T38_NEGOTIATED:
1566                                 ast_log(LOG_NOTICE, "Negotiated T.38 for send on %s\n", chan->name);
1567                                 t38_parameters_ast_to_fax(&details->their_t38_parameters, parameters);
1568                                 details->caps &= ~AST_FAX_TECH_AUDIO;
1569                                 report_fax_status(chan, details, "T.38 Negotiated");
1570                                 ms = 0;
1571                                 break;
1572                         default:
1573                                 break;
1574                         }
1575                 }
1576                 ast_frfree(frame);
1577         }
1578
1579         ast_playtones_stop(chan);
1580
1581         if (ast_channel_get_t38_state(chan) == T38_STATE_NEGOTIATED) {
1582                 return 0;
1583         }
1584
1585         /* T.38 negotiation did not happen, initiate a switch if requested */
1586         if (details->option.request_t38 == AST_FAX_OPTFLAG_TRUE) {
1587                 ast_log(LOG_NOTICE, "Negotiating T.38 for send on %s\n", chan->name);
1588
1589                 /* wait up to five seconds for negotiation to complete */
1590                 ms = 5000;
1591
1592                 /* set parameters based on the session's parameters */
1593                 t38_parameters_fax_to_ast(&t38_parameters, &details->our_t38_parameters);
1594                 t38_parameters.request_response = AST_T38_REQUEST_NEGOTIATE;
1595                 if ((ast_indicate_data(chan, AST_CONTROL_T38_PARAMETERS, &t38_parameters, sizeof(t38_parameters)) != 0)) {
1596                         return -1;
1597                 }
1598
1599                 while (ms > 0) {
1600                         ms = ast_waitfor(chan, ms);
1601                         if (ms < 0) {
1602                                 ast_log(LOG_WARNING, "error on '%s' while waiting for T.38 negotiation.\n", chan->name);
1603                                 return -1;
1604                         }
1605
1606                         if (ms == 0) { /* all done, nothing happened */
1607                                 ast_log(LOG_WARNING, "channel '%s' timed-out during the T.38 negotiation.\n", chan->name);
1608                                 details->caps &= ~AST_FAX_TECH_T38;
1609                                 break;
1610                         }
1611
1612                         if (!(frame = ast_read(chan))) {
1613                                 ast_log(LOG_WARNING, "error on '%s' while waiting for T.38 negotiation.\n", chan->name);
1614                                 return -1;
1615                         }
1616
1617                         if ((frame->frametype == AST_FRAME_CONTROL) &&
1618                                         (frame->subclass.integer == AST_CONTROL_T38_PARAMETERS) &&
1619                                         (frame->datalen == sizeof(t38_parameters))) {
1620                                 struct ast_control_t38_parameters *parameters = frame->data.ptr;
1621
1622                                 switch (parameters->request_response) {
1623                                 case AST_T38_REQUEST_NEGOTIATE:
1624                                         t38_parameters_fax_to_ast(&t38_parameters, &details->our_t38_parameters);
1625                                         t38_parameters.request_response = AST_T38_NEGOTIATED;
1626                                         ast_indicate_data(chan, AST_CONTROL_T38_PARAMETERS, &t38_parameters, sizeof(t38_parameters));
1627                                         break;
1628                                 case AST_T38_NEGOTIATED:
1629                                         ast_log(LOG_NOTICE, "Negotiated T.38 for receive on %s\n", chan->name);
1630                                         t38_parameters_ast_to_fax(&details->their_t38_parameters, parameters);
1631                                         details->caps &= ~AST_FAX_TECH_AUDIO;
1632                                         report_fax_status(chan, details, "T.38 Negotiated");
1633                                         ms = 0;
1634                                         break;
1635                                 case AST_T38_REFUSED:
1636                                         ast_log(LOG_WARNING, "channel '%s' refused to negotiate T.38\n", chan->name);
1637                                         details->caps &= ~AST_FAX_TECH_T38;
1638                                         ms = 0;
1639                                         break;
1640                                 default:
1641                                         ast_log(LOG_ERROR, "channel '%s' failed to negotiate T.38\n", chan->name);
1642                                         details->caps &= ~AST_FAX_TECH_T38;
1643                                         ms = 0;
1644                                         break;
1645                                 }
1646                         }
1647                         ast_frfree(frame);
1648                 }
1649
1650                 /* if T.38 was negotiated, we are done initializing */
1651                 if (ast_channel_get_t38_state(chan) == T38_STATE_NEGOTIATED) {
1652                         return 0;
1653                 }
1654
1655                 /* send one more CNG tone to get audio going again for some
1656                  * carriers if we are going to fall back to audio mode */
1657                 if (details->option.allow_audio == AST_FAX_OPTFLAG_TRUE) {
1658                         if (ast_playtones_start(chan, 1024, "!1100/500,!0/3000", 1)) {
1659                                 ast_log(LOG_ERROR, "error generating second CNG tone on %s\n", chan->name);
1660                                 return -1;
1661                         }
1662
1663                         ms = 3500;
1664                         while (ms > 0) {
1665                                 ms = ast_waitfor(chan, ms);
1666                                 if (ms < 0) {
1667                                         ast_log(LOG_ERROR, "error while generating second CNG tone on %s\n", chan->name);
1668                                         ast_playtones_stop(chan);
1669                                         return -1;
1670                                 }
1671
1672                                 if (ms == 0) { /* all done, nothing happened */
1673                                         break;
1674                                 }
1675
1676                                 if (!(frame = ast_read(chan))) {
1677                                         ast_log(LOG_ERROR, "error reading frame while generating second CNG tone on %s\n", chan->name);
1678                                         ast_playtones_stop(chan);
1679                                         return -1;
1680                                 }
1681
1682                                 if ((frame->frametype == AST_FRAME_CONTROL) &&
1683                                                 (frame->subclass.integer == AST_CONTROL_T38_PARAMETERS) &&
1684                                                 (frame->datalen == sizeof(t38_parameters))) {
1685                                         struct ast_control_t38_parameters *parameters = frame->data.ptr;
1686
1687                                         switch (parameters->request_response) {
1688                                         case AST_T38_REQUEST_NEGOTIATE:
1689                                                 /* the other end has requested a switch to T.38, so reply that we are willing, if we can
1690                                                  * do T.38 as well
1691                                                  */
1692                                                 t38_parameters_fax_to_ast(&t38_parameters, &details->our_t38_parameters);
1693                                                 t38_parameters.request_response = (details->caps & AST_FAX_TECH_T38) ? AST_T38_NEGOTIATED : AST_T38_REFUSED;
1694                                                 ast_indicate_data(chan, AST_CONTROL_T38_PARAMETERS, &t38_parameters, sizeof(t38_parameters));
1695                                                 ast_playtones_stop(chan);
1696                                                 break;
1697                                         case AST_T38_NEGOTIATED:
1698                                                 ast_log(LOG_NOTICE, "Negotiated T.38 for send on %s\n", chan->name);
1699                                                 t38_parameters_ast_to_fax(&details->their_t38_parameters, parameters);
1700                                                 details->caps &= ~AST_FAX_TECH_AUDIO;
1701                                                 report_fax_status(chan, details, "T.38 Negotiated");
1702                                                 ms = 0;
1703                                                 break;
1704                                         default:
1705                                                 break;
1706                                         }
1707                                 }
1708                                 ast_frfree(frame);
1709                         }
1710
1711                         ast_playtones_stop(chan);
1712
1713                         /* if T.38 was negotiated, we are done initializing */
1714                         if (ast_channel_get_t38_state(chan) == T38_STATE_NEGOTIATED) {
1715                                 return 0;
1716                         }
1717                 }
1718         }
1719
1720         /* if we made it here, then T.38 failed, check the 'f' flag */
1721         if (details->option.allow_audio == AST_FAX_OPTFLAG_FALSE) {
1722                 ast_log(LOG_WARNING, "Audio FAX not allowed on channel '%s' and T.38 negotiation failed; aborting.\n", chan->name);
1723                 return -1;
1724         }
1725
1726         /* ok, audio fallback is allowed */
1727         details->caps |= AST_FAX_TECH_AUDIO;
1728
1729         return 0;
1730 }
1731
1732
1733 /*! \brief initiate a send FAX session */
1734 static int sendfax_exec(struct ast_channel *chan, const char *data)
1735 {
1736         char *parse, *filenames, *c;
1737         int channel_alive, file_count;
1738         struct ast_fax_session_details *details;
1739         struct ast_fax_document *doc;
1740         AST_DECLARE_APP_ARGS(args,
1741                 AST_APP_ARG(filenames);
1742                 AST_APP_ARG(options);
1743         );
1744         struct ast_flags opts = { 0, };
1745         struct manager_event_info info;
1746
1747         /* Get a requirement structure and set it.  This structure is used
1748          * to tell the FAX technology module about the higher level FAX session */
1749         if (!(details = find_or_create_details(chan))) {
1750                 ast_log(LOG_ERROR, "System cannot provide memory for session requirements.\n");
1751                 return -1;
1752         }
1753
1754         if (ast_strlen_zero(data)) {
1755                 ast_string_field_set(details, error, "INVALID_ARGUMENTS");
1756                 ast_string_field_set(details, resultstr, "invalid arguments");
1757                 ast_log(LOG_WARNING, "%s requires an argument (filename[&filename[&filename]][,options])\n", app_sendfax);
1758                 return -1;
1759         }
1760         parse = ast_strdupa(data);
1761         AST_STANDARD_APP_ARGS(args, parse);
1762
1763         /* initialize output channel variables */
1764         pbx_builtin_setvar_helper(chan, "FAXSTATUS", "FAILED");
1765         pbx_builtin_setvar_helper(chan, "FAXERROR", "Application Problems");
1766         pbx_builtin_setvar_helper(chan, "FAXSTATUSSTRING", "Invalid application arguments.");
1767         pbx_builtin_setvar_helper(chan, "REMOTESTATIONID", NULL);
1768         pbx_builtin_setvar_helper(chan, "FAXPAGES", "0");
1769         pbx_builtin_setvar_helper(chan, "FAXBITRATE", NULL);
1770         pbx_builtin_setvar_helper(chan, "FAXRESOLUTION", NULL);
1771
1772         if (!ast_strlen_zero(args.options) &&
1773             ast_app_parse_options(fax_exec_options, &opts, NULL, args.options)) {
1774                 return -1;
1775         }
1776         if (ast_strlen_zero(args.filenames)) {
1777                 ast_string_field_set(details, error, "INVALID_ARGUMENTS");
1778                 ast_string_field_set(details, resultstr, "invalid arguments");
1779                 ast_log(LOG_WARNING, "%s requires an argument (filename[&filename[&filename]],options])\n", app_sendfax);
1780                 return -1;
1781         }
1782         
1783         /* check for unsupported FAX application options */
1784         if (ast_test_flag(&opts, OPT_CALLERMODE) || ast_test_flag(&opts, OPT_CALLEDMODE)) {
1785                 ast_string_field_set(details, error, "INVALID_ARGUMENTS");
1786                 ast_string_field_set(details, resultstr, "invalid arguments");
1787                 ast_log(LOG_WARNING, "%s does not support polling\n", app_sendfax);
1788                 return -1;
1789         }
1790
1791         /* make sure the channel is up */
1792         if (chan->_state != AST_STATE_UP) {
1793                 if (ast_answer(chan)) {
1794                         ast_log(LOG_WARNING, "Channel '%s' failed answer attempt.\n", chan->name);
1795                         return -1;
1796                 }
1797         }
1798
1799         ast_atomic_fetchadd_int(&faxregistry.fax_tx_attempts, 1);
1800         
1801         pbx_builtin_setvar_helper(chan, "FAXERROR", "Channel Problems");
1802         pbx_builtin_setvar_helper(chan, "FAXSTATUSSTRING", "Error before FAX transmission started.");
1803
1804         file_count = 0;
1805         filenames = args.filenames;
1806         while ((c = strsep(&filenames, "&"))) {
1807                 if (access(c, (F_OK | R_OK)) < 0) {
1808                         ast_string_field_set(details, error, "FILE_ERROR");
1809                         ast_string_field_set(details, resultstr, "error reading file");
1810                         ast_log(LOG_ERROR, "access failure.  Verify '%s' exists and check permissions.\n", args.filenames);
1811                         ao2_ref(details, -1);
1812                         return -1;
1813                 }
1814
1815                 if (!(doc = ast_calloc(1, sizeof(*doc) + strlen(c) + 1))) {
1816                         ast_string_field_set(details, error, "MEMORY_ERROR");
1817                         ast_string_field_set(details, resultstr, "error allocating memory");
1818                         ast_log(LOG_ERROR, "System cannot provide memory for session requirements.\n");
1819                         ao2_ref(details, -1);
1820                         return -1;
1821                 }
1822
1823                 strcpy(doc->filename, c);
1824                 AST_LIST_INSERT_TAIL(&details->documents, doc, next);
1825                 file_count++;
1826         }
1827
1828         if (file_count > 1) {
1829                 details->caps |= AST_FAX_TECH_MULTI_DOC;
1830         }
1831
1832         ast_verb(3, "Channel '%s' sending FAX:\n", chan->name);
1833         AST_LIST_TRAVERSE(&details->documents, doc, next) {
1834                 ast_verb(3, "   %s\n", doc->filename);
1835         }
1836
1837         details->caps = AST_FAX_TECH_SEND;
1838
1839         /* check for debug */
1840         if (ast_test_flag(&opts, OPT_DEBUG) || global_fax_debug) {
1841                 details->option.debug = AST_FAX_OPTFLAG_TRUE;
1842         }
1843
1844         /* check for request for status events */
1845         if (ast_test_flag(&opts, OPT_STATUS)) {
1846                 details->option.statusevents = AST_FAX_OPTFLAG_TRUE;
1847         }
1848
1849         if ((ast_channel_get_t38_state(chan) == T38_STATE_UNAVAILABLE) ||
1850             ast_test_flag(&opts, OPT_ALLOWAUDIO)) {
1851                 details->option.allow_audio = AST_FAX_OPTFLAG_TRUE;
1852         }
1853
1854         if (ast_test_flag(&opts, OPT_REQUEST_T38)) {
1855                 details->option.request_t38 = AST_FAX_OPTFLAG_TRUE;
1856         }
1857
1858         if (set_fax_t38_caps(chan, details)) {
1859                 ast_string_field_set(details, error, "T38_NEG_ERROR");
1860                 ast_string_field_set(details, resultstr, "error negotiating T.38");
1861                 ao2_ref(details, -1);
1862                 return -1;
1863         }
1864
1865         if (details->caps & AST_FAX_TECH_T38) {
1866                 if (sendfax_t38_init(chan, details)) {
1867                         ast_string_field_set(details, error, "T38_NEG_ERROR");
1868                         ast_string_field_set(details, resultstr, "error negotiating T.38");
1869                         ao2_ref(details, -1);
1870                         ast_log(LOG_ERROR, "error initializing channel '%s' in T.38 mode\n", chan->name);
1871                         return -1;
1872                 }
1873         } else {
1874                 details->option.send_cng = 1;
1875         }
1876
1877         if ((channel_alive = generic_fax_exec(chan, details)) < 0) {
1878                 ast_atomic_fetchadd_int(&faxregistry.fax_failures, 1);
1879         }
1880
1881         if (ast_channel_get_t38_state(chan) == T38_STATE_NEGOTIATED) {
1882                 if (disable_t38(chan)) {
1883                         ast_log(LOG_WARNING, "error disabling T.38 mode on %s\n", chan->name);
1884                 }
1885         }
1886
1887         if (!(filenames = generate_filenames_string(details, "FileName: ", "\r\n"))) {
1888                 ast_log(LOG_ERROR, "Error generating SendFAX manager event\n");
1889                 ao2_ref(details, -1);
1890                 return (!channel_alive) ? -1 : 0;
1891         }
1892
1893         /* send out the AMI completion event */
1894         ast_channel_lock(chan);
1895         get_manager_event_info(chan, &info);
1896         manager_event(EVENT_FLAG_CALL,
1897                       "SendFAX", 
1898                       "Channel: %s\r\n"
1899                       "Context: %s\r\n"
1900                       "Exten: %s\r\n"
1901                       "CallerID: %s\r\n"
1902                       "RemoteStationID: %s\r\n"
1903                       "LocalStationID: %s\r\n"
1904                       "PagesTransferred: %s\r\n"
1905                       "Resolution: %s\r\n"
1906                       "TransferRate: %s\r\n"
1907                       "%s\r\n",
1908                       chan->name,
1909                       info.context,
1910                       info.exten,
1911                       info.cid,
1912                       pbx_builtin_getvar_helper(chan, "REMOTESTATIONID"),
1913                       pbx_builtin_getvar_helper(chan, "LOCALSTATIONID"),
1914                       pbx_builtin_getvar_helper(chan, "FAXPAGES"),
1915                       pbx_builtin_getvar_helper(chan, "FAXRESOLUTION"),
1916                       pbx_builtin_getvar_helper(chan, "FAXBITRATE"),
1917                       filenames);
1918         ast_channel_unlock(chan);
1919
1920         ast_free(filenames);
1921
1922         ao2_ref(details, -1);
1923
1924         /* If the channel hungup return -1; otherwise, return 0 to continue in the dialplan */
1925         return (!channel_alive) ? -1 : 0;
1926 }
1927
1928 /*! \brief hash callback for ao2 */
1929 static int session_hash_cb(const void *obj, const int flags)
1930 {
1931         const struct ast_fax_session *s = obj;
1932
1933         return s->id;
1934 }
1935
1936 /*! \brief compare callback for ao2 */
1937 static int session_cmp_cb(void *obj, void *arg, int flags)
1938 {
1939         struct ast_fax_session *lhs = obj, *rhs = arg;
1940
1941         return (lhs->id == rhs->id) ? CMP_MATCH | CMP_STOP : 0;
1942 }
1943
1944 /*! \brief fax session tab completion */
1945 static char *fax_session_tab_complete(struct ast_cli_args *a)
1946 {
1947         int tklen;
1948         int wordnum = 0;
1949         char *name = NULL;
1950         struct ao2_iterator i;
1951         struct ast_fax_session *s;
1952         char tbuf[5];
1953
1954         if (a->pos != 3) {
1955                 return NULL;
1956         }
1957
1958         tklen = strlen(a->word);
1959         i = ao2_iterator_init(faxregistry.container, 0);
1960         while ((s = ao2_iterator_next(&i))) {
1961                 snprintf(tbuf, sizeof(tbuf), "%d", s->id);
1962                 if (!strncasecmp(a->word, tbuf, tklen) && ++wordnum > a->n) {
1963                         name = ast_strdup(tbuf);
1964                         ao2_ref(s, -1);
1965                         break;
1966                 }
1967                 ao2_ref(s, -1);
1968         }
1969         if (ao2_iterator_destroy != NULL) {
1970                 ao2_iterator_destroy(&i);
1971         }
1972         return name;
1973 }
1974
1975 static char *cli_fax_show_version(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
1976 {
1977         struct fax_module *fax;
1978
1979         switch(cmd) {
1980         case CLI_INIT:
1981                 e->command = "fax show version";
1982                 e->usage =
1983                         "Usage: fax show version\n"
1984                         "       Show versions of FAX For Asterisk components.\n";
1985                 return NULL;
1986         case CLI_GENERATE:
1987                 return NULL;
1988         }
1989
1990         if (a->argc != 3) {
1991                 return CLI_SHOWUSAGE;
1992         }
1993
1994         ast_cli(a->fd, "FAX For Asterisk Components:\n");
1995         ast_cli(a->fd, "\tApplications: %s\n", ast_get_version());
1996         AST_RWLIST_RDLOCK(&faxmodules);
1997         AST_RWLIST_TRAVERSE(&faxmodules, fax, list) {
1998                 ast_cli(a->fd, "\t%s: %s\n", fax->tech->description, fax->tech->version);
1999         }
2000         AST_RWLIST_UNLOCK(&faxmodules);
2001         ast_cli(a->fd, "\n");
2002
2003         return CLI_SUCCESS;
2004 }
2005
2006 /*! \brief enable FAX debugging */
2007 static char *cli_fax_set_debug(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
2008 {
2009         int flag;
2010         const char *what;
2011
2012         switch (cmd) {
2013         case CLI_INIT:
2014                 e->command = "fax set debug {on|off}";
2015                 e->usage = 
2016                         "Usage: fax set debug { on | off }\n"
2017                         "       Enable/Disable FAX debugging on new FAX sessions.  The basic FAX debugging will result in\n"
2018                         "       additional events sent to manager sessions with 'call' class permissions.  When\n"
2019                         "       verbosity is greater than '5' events will be displayed to the console and audio versus\n"
2020                         "       energy analysis will be performed and displayed to the console.\n";
2021                 return NULL;
2022         case CLI_GENERATE:
2023                 return NULL;
2024         }
2025
2026         what = a->argv[e->args-1];      /* guaranteed to exist */
2027         if (!strcasecmp(what, "on")) {
2028                 flag = 1;
2029         } else if (!strcasecmp(what, "off")) {
2030                 flag = 0;
2031         } else {
2032                 return CLI_SHOWUSAGE;
2033         }
2034
2035         global_fax_debug = flag;
2036         ast_cli(a->fd, "\n\nFAX Debug %s\n\n", (flag) ? "Enabled" : "Disabled");
2037
2038         return CLI_SUCCESS;
2039 }
2040
2041 /*! \brief display registered FAX capabilities */
2042 static char *cli_fax_show_capabilities(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
2043 {
2044         struct fax_module *fax;
2045         unsigned int num_modules = 0;
2046         
2047         switch (cmd) {
2048         case CLI_INIT:
2049                 e->command = "fax show capabilities";
2050                 e->usage = 
2051                         "Usage: fax show capabilities\n"
2052                         "       Shows the capabilities of the registered FAX technology modules\n";
2053                 return NULL;
2054         case CLI_GENERATE:
2055                 return NULL;
2056         }
2057
2058         ast_cli(a->fd, "\n\nRegistered FAX Technology Modules:\n\n");
2059         AST_RWLIST_RDLOCK(&faxmodules);
2060         AST_RWLIST_TRAVERSE(&faxmodules, fax, list) {
2061                 ast_cli(a->fd, "%-15s : %s\n%-15s : %s\n%-15s : ", "Type", fax->tech->type, "Description", fax->tech->description, "Capabilities");
2062                 fax->tech->cli_show_capabilities(a->fd);
2063                 num_modules++;
2064         }
2065         AST_RWLIST_UNLOCK(&faxmodules);
2066         ast_cli(a->fd, "%d registered modules\n\n", num_modules);
2067
2068         return CLI_SUCCESS;
2069 }
2070
2071 /*! \brief display global defaults and settings */
2072 static char *cli_fax_show_settings(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
2073 {
2074         struct fax_module *fax;
2075         char modems[128] = "";
2076
2077         switch (cmd) {
2078         case CLI_INIT:
2079                 e->command = "fax show settings";
2080                 e->usage =
2081                         "Usage: fax show settings\n"
2082                         "       Show the global settings and defaults of both the FAX core and technology modules\n";
2083                 return NULL;
2084         case CLI_GENERATE:
2085                 return NULL;
2086         }
2087
2088         ast_cli(a->fd, "FAX For Asterisk Settings:\n");
2089         ast_cli(a->fd, "\tECM: %s\n", general_options.ecm ? "Enabled" : "Disabled");
2090         ast_cli(a->fd, "\tStatus Events: %s\n",  general_options.statusevents ? "On" : "Off");
2091         ast_cli(a->fd, "\tMinimum Bit Rate: %d\n", general_options.minrate);
2092         ast_cli(a->fd, "\tMaximum Bit Rate: %d\n", general_options.maxrate);
2093         ast_fax_modem_to_str(general_options.modems, modems, sizeof(modems));
2094         ast_cli(a->fd, "\tModem Modulations Allowed: %s\n", modems);
2095         ast_cli(a->fd, "\n\nFAX Technology Modules:\n\n");
2096         AST_RWLIST_RDLOCK(&faxmodules);
2097         AST_RWLIST_TRAVERSE(&faxmodules, fax, list) {
2098                 ast_cli(a->fd, "%s (%s) Settings:\n", fax->tech->type, fax->tech->description);
2099                 fax->tech->cli_show_settings(a->fd);
2100         }
2101         AST_RWLIST_UNLOCK(&faxmodules);
2102
2103         return CLI_SUCCESS;
2104 }
2105
2106 /*! \brief display details of a specified fax session */
2107 static char *cli_fax_show_session(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
2108 {
2109         struct ast_fax_session *s, tmp;
2110
2111         switch (cmd) {
2112         case CLI_INIT:
2113                 e->command = "fax show session";
2114                 e->usage =
2115                         "Usage: fax show session <session number>\n"
2116                         "       Shows status of the named FAX session\n";
2117                 return NULL;
2118         case CLI_GENERATE:
2119                 return fax_session_tab_complete(a);
2120         }
2121
2122         if (a->argc != 4) {
2123                 return CLI_SHOWUSAGE;
2124         }
2125
2126         if (sscanf(a->argv[3], "%d", &tmp.id) != 1) {
2127                 ast_log(LOG_ERROR, "invalid session id: '%s'\n", a->argv[3]);
2128                 return RESULT_SUCCESS;
2129         }
2130
2131         ast_cli(a->fd, "\nFAX Session Details:\n--------------------\n\n");
2132         s = ao2_find(faxregistry.container, &tmp, OBJ_POINTER);
2133         if (s) {
2134                 s->tech->cli_show_session(s, a->fd);
2135                 ao2_ref(s, -1);
2136         }
2137         ast_cli(a->fd, "\n\n");
2138
2139         return CLI_SUCCESS;
2140 }
2141         
2142 /*! \brief display fax stats */
2143 static char *cli_fax_show_stats(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
2144 {
2145         struct fax_module *fax;
2146         
2147         switch (cmd) {
2148         case CLI_INIT:
2149                 e->command = "fax show stats";
2150                 e->usage =
2151                         "Usage: fax show stats\n"
2152                         "       Shows a statistical summary of FAX transmissions\n";
2153                 return NULL;
2154         case CLI_GENERATE:
2155                 return NULL;
2156         }
2157
2158         ast_cli(a->fd, "\nFAX Statistics:\n---------------\n\n");
2159         ast_cli(a->fd, "%-20.20s : %d\n", "Current Sessions", faxregistry.active_sessions);
2160         ast_cli(a->fd, "%-20.20s : %d\n", "Transmit Attempts", faxregistry.fax_tx_attempts);
2161         ast_cli(a->fd, "%-20.20s : %d\n", "Receive Attempts", faxregistry.fax_rx_attempts);
2162         ast_cli(a->fd, "%-20.20s : %d\n", "Completed FAXes", faxregistry.fax_complete);
2163         ast_cli(a->fd, "%-20.20s : %d\n", "Failed FAXes", faxregistry.fax_failures);
2164         AST_RWLIST_RDLOCK(&faxmodules);
2165         AST_RWLIST_TRAVERSE(&faxmodules, fax, list) {
2166                 fax->tech->cli_show_stats(a->fd);
2167         }
2168         AST_RWLIST_UNLOCK(&faxmodules);
2169         ast_cli(a->fd, "\n\n");
2170
2171         return CLI_SUCCESS;
2172 }
2173
2174 /*! \brief display fax sessions */
2175 static char *cli_fax_show_sessions(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
2176 {
2177         struct ast_fax_session *s;
2178         struct ao2_iterator i;
2179         int session_count;
2180         char *filenames;
2181
2182         switch (cmd) {
2183         case CLI_INIT:
2184                 e->command = "fax show sessions";
2185                 e->usage =
2186                         "Usage: fax show sessions\n"
2187                         "       Shows the current FAX sessions\n";
2188                 return NULL;
2189         case CLI_GENERATE:
2190                 return NULL;
2191         }
2192
2193         ast_cli(a->fd, "\nCurrent FAX Sessions:\n\n");
2194         ast_cli(a->fd, "%-20.20s %-10.10s %-10.10s %-5.5s %-10.10s %-15.15s %-30.30s\n",
2195                 "Channel", "Tech", "FAXID", "Type", "Operation", "State", "File(s)");
2196         i = ao2_iterator_init(faxregistry.container, 0);
2197         while ((s = ao2_iterator_next(&i))) {
2198                 ao2_lock(s);
2199
2200                 if (!(filenames = generate_filenames_string(s->details, "", ", "))) {
2201                         ast_log(LOG_ERROR, "error printing filenames for 'fax show sessions' command");
2202                         ao2_unlock(s);
2203                         ao2_ref(s, -1);
2204                         if (ao2_iterator_destroy != NULL) {
2205                                 ao2_iterator_destroy(&i);
2206                         }
2207                         return CLI_FAILURE;
2208                 }
2209
2210                 ast_cli(a->fd, "%-20.20s %-10.10s %-10d %-5.5s %-10.10s %-15.15s %-30s\n",
2211                         s->channame, s->tech->type, s->id,
2212                         (s->details->caps & AST_FAX_TECH_AUDIO) ? "G.711" : "T.38",
2213                         (s->details->caps & AST_FAX_TECH_SEND) ? "send" : "receive",
2214                         ast_fax_state_to_str(s->state), filenames);
2215
2216                 ast_free(filenames);
2217                 ao2_unlock(s);
2218                 ao2_ref(s, -1);
2219         }
2220         if (ao2_iterator_destroy != NULL) {
2221                 ao2_iterator_destroy(&i);
2222         }
2223         session_count = ao2_container_count(faxregistry.container);
2224         ast_cli(a->fd, "\n%d FAX sessions\n\n", session_count);
2225
2226         return CLI_SUCCESS;
2227 }
2228
2229 static struct ast_cli_entry fax_cli[] = {
2230         AST_CLI_DEFINE(cli_fax_show_version, "Show versions of FAX For Asterisk components"),
2231         AST_CLI_DEFINE(cli_fax_set_debug, "Enable/Disable FAX debugging on new FAX sessions"),
2232         AST_CLI_DEFINE(cli_fax_show_capabilities, "Show the capabilities of the registered FAX technology modules"),
2233         AST_CLI_DEFINE(cli_fax_show_settings, "Show the global settings and defaults of both the FAX core and technology modules"),
2234         AST_CLI_DEFINE(cli_fax_show_session, "Show the status of the named FAX sessions"),
2235         AST_CLI_DEFINE(cli_fax_show_sessions, "Show the current FAX sessions"),
2236         AST_CLI_DEFINE(cli_fax_show_stats, "Summarize FAX session history"),
2237 };
2238
2239 /*! \brief configure res_fax */
2240 static int set_config(const char *config_file)
2241 {
2242         struct ast_config *cfg;
2243         struct ast_variable *v;
2244         struct ast_flags config_flags = { 0 };
2245
2246         /* set defaults */      
2247         general_options.minrate = RES_FAX_MINRATE;
2248         general_options.maxrate = RES_FAX_MAXRATE;      
2249         general_options.statusevents = RES_FAX_STATUSEVENTS;
2250         general_options.modems = RES_FAX_MODEM;
2251         general_options.ecm = AST_FAX_OPTFLAG_TRUE;
2252
2253         /* read configuration */
2254         if (!(cfg = ast_config_load2(config_file, "res_fax", config_flags))) {
2255                 ast_log(LOG_NOTICE, "Configuration file '%s' not found, using default options.\n", config_file);
2256                 return 0;
2257         }
2258         if (cfg == CONFIG_STATUS_FILEUNCHANGED) {
2259                 ast_clear_flag(&config_flags, CONFIG_FLAG_FILEUNCHANGED);
2260                 cfg = ast_config_load2(config_file, "res_fax", config_flags);
2261         }
2262
2263         /* create configuration */
2264         for (v = ast_variable_browse(cfg, "general"); v; v = v->next) {
2265                 int rate;
2266
2267                 if (!strcasecmp(v->name, "minrate")) {
2268                         ast_debug(3, "reading minrate '%s' from configuration file\n", v->value);
2269                         if ((rate = fax_rate_str_to_int(v->value)) == 0) {
2270                                 ast_config_destroy(cfg);
2271                                 return -1;
2272                         }
2273                         general_options.minrate = rate;
2274                 } else if (!strcasecmp(v->name, "maxrate")) {
2275                         ast_debug(3, "reading maxrate '%s' from configuration file\n", v->value);
2276                         if ((rate = fax_rate_str_to_int(v->value)) == 0) {
2277                                 ast_config_destroy(cfg);
2278                                 return -1;
2279                         }
2280                         general_options.maxrate = rate;
2281                 } else if (!strcasecmp(v->name, "statusevents")) {
2282                         ast_debug(3, "reading statusevents '%s' from configuration file\n", v->value);
2283                         general_options.statusevents = ast_true(v->value);
2284                 } else if (!strcasecmp(v->name, "ecm")) {
2285                         ast_debug(3, "reading ecm '%s' from configuration file\n", v->value);
2286                         general_options.ecm = ast_true(v->value);
2287                 } else if ((!strcasecmp(v->name, "modem")) || (!strcasecmp(v->name, "modems"))) {
2288                         general_options.modems = 0;
2289                         update_modem_bits(&general_options.modems, v->value);
2290                 }
2291         }
2292
2293         ast_config_destroy(cfg);
2294
2295         return 0;
2296 }
2297
2298 /*! \brief FAXOPT read function returns the contents of a FAX option */
2299 static int acf_faxopt_read(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t len)
2300 {
2301         struct ast_fax_session_details *details = find_details(chan);
2302         int res = 0;
2303         char *filenames;
2304
2305         if (!details) {
2306                 ast_log(LOG_ERROR, "channel '%s' can't read FAXOPT(%s) because it has never been written.\n", chan->name, data);
2307                 return -1;
2308         }
2309         if (!strcasecmp(data, "ecm")) {
2310                 ast_copy_string(buf, details->option.ecm ? "yes" : "no", len);
2311         } else if (!strcasecmp(data, "error")) {
2312                 ast_copy_string(buf, details->error, len);
2313         } else if (!strcasecmp(data, "filename")) {
2314                 if (AST_LIST_EMPTY(&details->documents)) {
2315                         ast_log(LOG_ERROR, "channel '%s' can't read FAXOPT(%s) because it has never been written.\n", chan->name, data);
2316                         res = -1;
2317                 } else {
2318                         ast_copy_string(buf, AST_LIST_FIRST(&details->documents)->filename, len);
2319                 }
2320         } else if (!strcasecmp(data, "filenames")) {
2321                 if (AST_LIST_EMPTY(&details->documents)) {
2322                         ast_log(LOG_ERROR, "channel '%s' can't read FAXOPT(%s) because it has never been written.\n", chan->name, data);
2323                         res = -1;
2324                 } else if ((filenames = generate_filenames_string(details, "", ","))) {
2325                         ast_copy_string(buf, filenames, len);
2326                         ast_free(filenames);
2327                 } else {
2328                         ast_log(LOG_ERROR, "channel '%s' can't read FAXOPT(%s), there was an error generating the filenames list.\n", chan->name, data);
2329                         res = -1;
2330                 }
2331         } else if (!strcasecmp(data, "headerinfo")) {
2332                 ast_copy_string(buf, details->headerinfo, len);
2333         } else if (!strcasecmp(data, "localstationid")) {
2334                 ast_copy_string(buf, details->localstationid, len);
2335         } else if (!strcasecmp(data, "maxrate")) {
2336                 snprintf(buf, len, "%d", details->maxrate);
2337         } else if (!strcasecmp(data, "minrate")) {
2338                 snprintf(buf, len, "%d", details->minrate);
2339         } else if (!strcasecmp(data, "pages")) {
2340                 snprintf(buf, len, "%d", details->pages_transferred);
2341         } else if (!strcasecmp(data, "rate")) {
2342                 ast_copy_string(buf, details->transfer_rate, len);
2343         } else if (!strcasecmp(data, "remotestationid")) {
2344                 ast_copy_string(buf, details->remotestationid, len);
2345         } else if (!strcasecmp(data, "resolution")) {
2346                 ast_copy_string(buf, details->resolution, len);
2347         } else if (!strcasecmp(data, "sessionid")) {
2348                 snprintf(buf, len, "%d", details->id);
2349         } else if (!strcasecmp(data, "status")) {
2350                 ast_copy_string(buf, details->result, len);
2351         } else if (!strcasecmp(data, "statusstr")) {
2352                 ast_copy_string(buf, details->resultstr, len);
2353         } else if ((!strcasecmp(data, "modem")) || (!strcasecmp(data, "modems"))) {
2354                 ast_fax_modem_to_str(details->modems, buf, len);
2355         } else {
2356                 ast_log(LOG_WARNING, "channel '%s' can't read FAXOPT(%s) because it is unhandled!\n", chan->name, data);
2357                 res = -1;
2358         }
2359         ao2_ref(details, -1);
2360
2361         return res;
2362 }
2363
2364 /*! \brief FAXOPT write function modifies the contents of a FAX option */
2365 static int acf_faxopt_write(struct ast_channel *chan, const char *cmd, char *data, const char *value)
2366 {
2367         int res = 0;
2368         struct ast_fax_session_details *details;
2369
2370         if (!(details = find_or_create_details(chan))) {
2371                 ast_log(LOG_WARNING, "channel '%s' can't set FAXOPT(%s) to '%s' because it failed to create a datastore.\n", chan->name, data, value);
2372                 return -1;
2373         }
2374         ast_debug(3, "channel '%s' setting FAXOPT(%s) to '%s'\n", chan->name, data, value);
2375
2376         if (!strcasecmp(data, "ecm")) {
2377                 const char *val = ast_skip_blanks(value);
2378                 if (ast_true(val)) {
2379                         details->option.ecm = AST_FAX_OPTFLAG_TRUE;
2380                 } else if (ast_false(val)) {
2381                         details->option.ecm = AST_FAX_OPTFLAG_FALSE;
2382                 } else {
2383                         ast_log(LOG_WARNING, "Unsupported value '%s' passed to FAXOPT(ecm).\n", value);
2384                 }
2385         } else if (!strcasecmp(data, "headerinfo")) {
2386                 ast_string_field_set(details, headerinfo, value);
2387         } else if (!strcasecmp(data, "localstationid")) {
2388                 ast_string_field_set(details, localstationid, value);
2389         } else if (!strcasecmp(data, "maxrate")) {
2390                 details->maxrate = fax_rate_str_to_int(value);
2391                 if (!details->maxrate) {
2392                         details->maxrate = ast_fax_maxrate();
2393                 }
2394         } else if (!strcasecmp(data, "minrate")) {
2395                 details->minrate = fax_rate_str_to_int(value);
2396                 if (!details->minrate) {
2397                         details->minrate = ast_fax_minrate();
2398                 }
2399         } else if ((!strcasecmp(data, "modem")) || (!strcasecmp(data, "modems"))) {
2400                 update_modem_bits(&details->modems, value);
2401         } else {
2402                 ast_log(LOG_WARNING, "channel '%s' set FAXOPT(%s) to '%s' is unhandled!\n", chan->name, data, value);
2403                 res = -1;
2404         }
2405
2406         ao2_ref(details, -1);
2407
2408         return res;
2409 }
2410
2411 /*! \brief FAXOPT dialplan function */
2412 struct ast_custom_function acf_faxopt = {
2413         .name = "FAXOPT",
2414         .read = acf_faxopt_read,
2415         .write = acf_faxopt_write,
2416 };
2417
2418 /*! \brief unload res_fax */
2419 static int unload_module(void)
2420 {
2421         ast_cli_unregister_multiple(fax_cli, ARRAY_LEN(fax_cli));
2422         
2423         if (ast_custom_function_unregister(&acf_faxopt) < 0) {
2424                 ast_log(LOG_WARNING, "failed to unregister function '%s'\n", acf_faxopt.name);
2425         }
2426
2427         if (ast_unregister_application(app_sendfax) < 0) {
2428                 ast_log(LOG_WARNING, "failed to unregister '%s'\n", app_sendfax);
2429         }
2430
2431         if (ast_unregister_application(app_receivefax) < 0) {
2432                 ast_log(LOG_WARNING, "failed to unregister '%s'\n", app_receivefax);
2433         }
2434
2435         if (fax_logger_level != -1) {
2436                 ast_logger_unregister_level("FAX");
2437         }
2438
2439         ao2_ref(faxregistry.container, -1);
2440
2441         return 0;
2442 }
2443
2444 /*! \brief load res_fax */
2445 static int load_module(void)
2446 {
2447         int res;
2448
2449         /* initialize the registry */
2450         faxregistry.active_sessions = 0;
2451         if (!(faxregistry.container = ao2_container_alloc(FAX_MAXBUCKETS, session_hash_cb, session_cmp_cb))) {
2452                 return AST_MODULE_LOAD_DECLINE;
2453         }
2454         
2455         if (set_config(config) < 0) {
2456                 ast_log(LOG_ERROR, "failed to load configuration file '%s'\n", config);
2457                 ao2_ref(faxregistry.container, -1);
2458                 return AST_MODULE_LOAD_DECLINE;
2459         }
2460
2461         /* register CLI operations and applications */
2462         if (ast_register_application_xml(app_sendfax, sendfax_exec) < 0) {
2463                 ast_log(LOG_WARNING, "failed to register '%s'.\n", app_sendfax);
2464                 ao2_ref(faxregistry.container, -1);
2465                 return AST_MODULE_LOAD_DECLINE;
2466         }
2467         if (ast_register_application_xml(app_receivefax, receivefax_exec) < 0) {
2468                 ast_log(LOG_WARNING, "failed to register '%s'.\n", app_receivefax);
2469                 ast_unregister_application(app_sendfax);
2470                 ao2_ref(faxregistry.container, -1);
2471                 return AST_MODULE_LOAD_DECLINE;
2472         }
2473         ast_cli_register_multiple(fax_cli, ARRAY_LEN(fax_cli));
2474         res = ast_custom_function_register(&acf_faxopt);        
2475         fax_logger_level = ast_logger_register_level("FAX");
2476
2477         return res;
2478 }
2479
2480
2481 AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_GLOBAL_SYMBOLS | AST_MODFLAG_LOAD_ORDER, "Generic FAX Applications",
2482                 .load = load_module,
2483                 .unload = unload_module,
2484                 .load_pri = AST_MODPRI_APP_DEPEND,
2485                );