Tue Sep 30 01:19:45 2008

Asterisk developer's documentation


autoservice.c File Reference

Automatic channel service routines. More...

#include "asterisk.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <signal.h>
#include <errno.h>
#include <unistd.h>
#include "asterisk/pbx.h"
#include "asterisk/frame.h"
#include "asterisk/sched.h"
#include "asterisk/options.h"
#include "asterisk/channel.h"
#include "asterisk/logger.h"
#include "asterisk/file.h"
#include "asterisk/translate.h"
#include "asterisk/manager.h"
#include "asterisk/chanvars.h"
#include "asterisk/linkedlists.h"
#include "asterisk/indications.h"
#include "asterisk/lock.h"
#include "asterisk/utils.h"

Include dependency graph for autoservice.c:

Go to the source code of this file.

Data Structures

struct  asent

Defines

#define MAX_AUTOMONS   1500

Functions

void ast_autoservice_init (void)
int ast_autoservice_start (struct ast_channel *chan)
 Automatically service a channel for us...
int ast_autoservice_stop (struct ast_channel *chan)
 Stop servicing a channel for us...
static AST_LIST_HEAD_STATIC (aslist, asent)
static void * autoservice_run (void *ign)

Variables

static int as_chan_list_state
static ast_cond_t as_cond
static pthread_t asthread = AST_PTHREADT_NULL


Detailed Description

Automatic channel service routines.

Author:
Mark Spencer <markster@digium.com>

Russell Bryant <russell@digium.com>

Definition in file autoservice.c.


Define Documentation

#define MAX_AUTOMONS   1500

Definition at line 55 of file autoservice.c.

Referenced by autoservice_run().


Function Documentation

void ast_autoservice_init ( void   ) 

Provided by astobj2.c Provided by autoservice.c

Definition at line 311 of file autoservice.c.

References as_cond, and ast_cond_init().

Referenced by main().

00312 {
00313    ast_cond_init(&as_cond, NULL);
00314 }

int ast_autoservice_start ( struct ast_channel chan  ) 

Automatically service a channel for us...

Return values:
0 success
-1 failure, or the channel is already being autoserviced

Definition at line 186 of file autoservice.c.

References as_cond, ast_calloc, ast_channel_lock, ast_channel_unlock, ast_cond_signal(), AST_FLAG_END_DTMF_ONLY, AST_LIST_EMPTY, AST_LIST_INSERT_HEAD, AST_LIST_LOCK, AST_LIST_REMOVE, AST_LIST_TRAVERSE, AST_LIST_UNLOCK, ast_log(), ast_pthread_create_background, AST_PTHREADT_NULL, ast_set_flag, ast_test_flag, asthread, autoservice_run(), asent::chan, free, LOG_WARNING, asent::orig_end_dtmf_flag, and asent::use_count.

Referenced by _macro_exec(), acf_curl_exec(), acf_cut_exec(), acf_odbc_read(), acf_odbc_write(), array(), ast_dtmf_stream(), ast_get_enum(), ast_get_srv(), ast_get_txt(), bridge_playfile(), builtin_atxfer(), builtin_automonitor(), builtin_blindtransfer(), conf_play(), feature_exec_app(), function_eval(), function_fieldqty(), function_realtime_read(), function_realtime_write(), osplookup_exec(), pbx_find_extension(), sla_station_exec(), smdi_msg_retrieve_read(), system_exec_helper(), and try_calling().

00187 {
00188    int res = 0;
00189    struct asent *as;
00190 
00191    /* Check if the channel already has autoservice */
00192    AST_LIST_LOCK(&aslist);
00193    AST_LIST_TRAVERSE(&aslist, as, list) {
00194       if (as->chan == chan) {
00195          as->use_count++;
00196          break;
00197       }
00198    }
00199    AST_LIST_UNLOCK(&aslist);
00200 
00201    if (as) {
00202       /* Entry exists, autoservice is already handling this channel */
00203       return 0;
00204    }
00205 
00206    if (!(as = ast_calloc(1, sizeof(*as))))
00207       return -1;
00208    
00209    /* New entry created */
00210    as->chan = chan;
00211    as->use_count = 1;
00212 
00213    ast_channel_lock(chan);
00214    as->orig_end_dtmf_flag = ast_test_flag(chan, AST_FLAG_END_DTMF_ONLY) ? 1 : 0;
00215    if (!as->orig_end_dtmf_flag)
00216       ast_set_flag(chan, AST_FLAG_END_DTMF_ONLY);
00217    ast_channel_unlock(chan);
00218 
00219    AST_LIST_LOCK(&aslist);
00220 
00221    if (AST_LIST_EMPTY(&aslist) && asthread != AST_PTHREADT_NULL) {
00222       ast_cond_signal(&as_cond);
00223    }
00224 
00225    AST_LIST_INSERT_HEAD(&aslist, as, list);
00226 
00227    if (asthread == AST_PTHREADT_NULL) { /* need start the thread */
00228       if (ast_pthread_create_background(&asthread, NULL, autoservice_run, NULL)) {
00229          ast_log(LOG_WARNING, "Unable to create autoservice thread :(\n");
00230          /* There will only be a single member in the list at this point,
00231             the one we just added. */
00232          AST_LIST_REMOVE(&aslist, as, list);
00233          free(as);
00234          asthread = AST_PTHREADT_NULL;
00235          res = -1;
00236       } else {
00237          pthread_kill(asthread, SIGURG);
00238       }
00239    }
00240 
00241    AST_LIST_UNLOCK(&aslist);
00242 
00243    return res;
00244 }

int ast_autoservice_stop ( struct ast_channel chan  ) 

Stop servicing a channel for us...

Return values:
0 success
-1 error, or the channel has been hungup

Definition at line 246 of file autoservice.c.

References ast_channel::_softhangup, as_chan_list_state, ast_clear_flag, AST_FLAG_END_DTMF_ONLY, ast_frfree, AST_LIST_LOCK, AST_LIST_REMOVE_CURRENT, AST_LIST_REMOVE_HEAD, AST_LIST_TRAVERSE_SAFE_BEGIN, AST_LIST_TRAVERSE_SAFE_END, AST_LIST_UNLOCK, AST_PTHREADT_NULL, ast_queue_frame(), asthread, asent::chan, f, free, asent::orig_end_dtmf_flag, and asent::use_count.

Referenced by _macro_exec(), acf_curl_exec(), acf_cut_exec(), acf_odbc_read(), acf_odbc_write(), array(), ast_dtmf_stream(), ast_get_enum(), ast_get_srv(), ast_get_txt(), ast_hangup(), bridge_playfile(), builtin_atxfer(), builtin_automonitor(), conf_play(), feature_exec_app(), finishup(), function_eval(), function_fieldqty(), function_realtime_read(), function_realtime_write(), osplookup_exec(), pbx_find_extension(), sla_station_exec(), smdi_msg_retrieve_read(), system_exec_helper(), and try_calling().

00247 {
00248    int res = -1;
00249    struct asent *as, *removed = NULL;
00250    struct ast_frame *f;
00251    int chan_list_state;
00252 
00253    AST_LIST_LOCK(&aslist);
00254 
00255    /* Save the autoservice channel list state.  We _must_ verify that the channel
00256     * list has been rebuilt before we return.  Because, after we return, the channel
00257     * could get destroyed and we don't want our poor autoservice thread to step on
00258     * it after its gone! */
00259    chan_list_state = as_chan_list_state;
00260 
00261    /* Find the entry, but do not free it because it still can be in the
00262       autoservice thread array */
00263    AST_LIST_TRAVERSE_SAFE_BEGIN(&aslist, as, list) {  
00264       if (as->chan == chan) {
00265          as->use_count--;
00266          if (as->use_count < 1) {
00267             AST_LIST_REMOVE_CURRENT(&aslist, list);
00268             removed = as;
00269          }
00270          break;
00271       }
00272    }
00273    AST_LIST_TRAVERSE_SAFE_END
00274 
00275    if (removed && asthread != AST_PTHREADT_NULL) {
00276       pthread_kill(asthread, SIGURG);
00277    }
00278 
00279    AST_LIST_UNLOCK(&aslist);
00280 
00281    if (!removed) {
00282       return 0;
00283    }
00284 
00285    /* Wait while autoservice thread rebuilds its list. */
00286    while (chan_list_state == as_chan_list_state) {
00287       usleep(1000);
00288    }
00289 
00290    /* Now autoservice thread should have no references to our entry
00291       and we can safely destroy it */
00292 
00293    if (!chan->_softhangup) {
00294       res = 0;
00295    }
00296 
00297    if (!as->orig_end_dtmf_flag) {
00298       ast_clear_flag(chan, AST_FLAG_END_DTMF_ONLY);
00299    }
00300 
00301    while ((f = AST_LIST_REMOVE_HEAD(&as->deferred_frames, frame_list))) {
00302       ast_queue_frame(chan, f);
00303       ast_frfree(f);
00304    }
00305 
00306    free(as);
00307 
00308    return res;
00309 }

static AST_LIST_HEAD_STATIC ( aslist  ,
asent   
) [static]

static void* autoservice_run ( void *  ign  )  [static]

Definition at line 75 of file autoservice.c.

References ast_channel::_softhangup, ast_cond_wait(), AST_CONTROL_HANGUP, AST_FRAME_CNG, AST_FRAME_CONTROL, AST_FRAME_DTMF_BEGIN, AST_FRAME_DTMF_END, AST_FRAME_HTML, AST_FRAME_IAX, AST_FRAME_IMAGE, AST_FRAME_MODEM, AST_FRAME_NULL, AST_FRAME_TEXT, AST_FRAME_VIDEO, AST_FRAME_VOICE, ast_frdup(), ast_frfree, AST_LIST_EMPTY, AST_LIST_INSERT_TAIL, AST_LIST_LOCK, AST_LIST_TRAVERSE, AST_LIST_UNLOCK, ast_log(), ast_read(), ast_waitfor_n(), asthread, asent::chan, f, ast_frame::frametype, LOG_WARNING, MAX_AUTOMONS, and ast_frame::subclass.

Referenced by ast_autoservice_start().

00076 {
00077    for (;;) {
00078       struct ast_channel *mons[MAX_AUTOMONS];
00079       struct asent *ents[MAX_AUTOMONS];
00080       struct ast_channel *chan;
00081       struct asent *as;
00082       int i, x = 0, ms = 50;
00083       struct ast_frame *f = NULL;
00084       struct ast_frame *defer_frame = NULL;
00085 
00086       AST_LIST_LOCK(&aslist);
00087 
00088       /* At this point, we know that no channels that have been removed are going
00089        * to get used again. */
00090       as_chan_list_state++;
00091 
00092       if (AST_LIST_EMPTY(&aslist)) {
00093          ast_cond_wait(&as_cond, &aslist.lock);
00094       }
00095 
00096       AST_LIST_TRAVERSE(&aslist, as, list) {
00097          if (!as->chan->_softhangup) {
00098             if (x < MAX_AUTOMONS) {
00099                ents[x] = as;
00100                mons[x++] = as->chan;
00101             } else {
00102                ast_log(LOG_WARNING, "Exceeded maximum number of automatic monitoring events.  Fix autoservice.c\n");
00103             }
00104          }
00105       }
00106 
00107       AST_LIST_UNLOCK(&aslist);
00108 
00109       chan = ast_waitfor_n(mons, x, &ms);
00110       if (!chan) {
00111          continue;
00112       }
00113 
00114       f = ast_read(chan);
00115    
00116       if (!f) {
00117          struct ast_frame hangup_frame = { 0, };
00118          /* No frame means the channel has been hung up.
00119           * A hangup frame needs to be queued here as ast_waitfor() may
00120           * never return again for the condition to be detected outside
00121           * of autoservice.  So, we'll leave a HANGUP queued up so the
00122           * thread in charge of this channel will know. */
00123 
00124          hangup_frame.frametype = AST_FRAME_CONTROL;
00125          hangup_frame.subclass = AST_CONTROL_HANGUP;
00126 
00127          defer_frame = &hangup_frame;
00128       } else {
00129 
00130          /* Do not add a default entry in this switch statement.  Each new
00131           * frame type should be addressed directly as to whether it should
00132           * be queued up or not. */
00133 
00134          switch (f->frametype) {
00135          /* Save these frames */
00136          case AST_FRAME_DTMF_END:
00137          case AST_FRAME_CONTROL:
00138          case AST_FRAME_TEXT:
00139          case AST_FRAME_IMAGE:
00140          case AST_FRAME_HTML:
00141             defer_frame = f;
00142             break;
00143 
00144          /* Throw these frames away */
00145          case AST_FRAME_DTMF_BEGIN:
00146          case AST_FRAME_VOICE:
00147          case AST_FRAME_VIDEO:
00148          case AST_FRAME_NULL:
00149          case AST_FRAME_IAX:
00150          case AST_FRAME_CNG:
00151          case AST_FRAME_MODEM:
00152             break;
00153          }
00154       }
00155 
00156       if (!defer_frame) {
00157          if (f) {
00158             ast_frfree(f);
00159          }
00160          continue;
00161       }
00162 
00163       if (f) {
00164          for (i = 0; i < x; i++) {
00165             struct ast_frame *dup_f;
00166             
00167             if (mons[i] != chan) {
00168                continue;
00169             }
00170             
00171             if ((dup_f = ast_frdup(f))) {
00172                AST_LIST_INSERT_TAIL(&ents[i]->deferred_frames, dup_f, frame_list);
00173             }
00174             
00175             break;
00176          }
00177          ast_frfree(f);
00178       }
00179    }
00180 
00181    asthread = AST_PTHREADT_NULL;
00182 
00183    return NULL;
00184 }


Variable Documentation

int as_chan_list_state [static]

Definition at line 73 of file autoservice.c.

Referenced by ast_autoservice_stop().

ast_cond_t as_cond [static]

Definition at line 69 of file autoservice.c.

Referenced by ast_autoservice_init(), and ast_autoservice_start().

pthread_t asthread = AST_PTHREADT_NULL [static]

Definition at line 71 of file autoservice.c.

Referenced by ast_autoservice_start(), ast_autoservice_stop(), and autoservice_run().


Generated on Tue Sep 30 01:19:45 2008 for Asterisk - the Open Source PBX by  doxygen 1.5.6