Fixed a severe issue where a misdn_read would lock the channel, but read would

not return because it blocks. later chan_misdn would try to queue a frame like
a AST_CONTROL_ANSWER which could result in a deadlock situation. misdn_read
will now not block forever anymore, and we don't queue the ANSWER frame at all
when we already was called with misdn_answer -> answer would be called twice.

Also we don't explicitly send a RELEASE_COMPLETE on receiption of a RELEASE
anymore, because mISDN does that for us, this resulted in a problem on some
switches, which would block our port after some calls for a short while.



git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@81367 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_misdn.c

@@ -2674,11 +2674,36 @@ static struct ast_frame  *misdn_read(struct ast_channel *ast)
 		return NULL;
 	}
 
-	len=read(tmp->pipe[0],tmp->ast_rd_buf,sizeof(tmp->ast_rd_buf));
+	fd_set rrfs;
+	struct timeval tv;
+	tv.tv_sec=0;
+	tv.tv_usec=20000;
 
-	if (len<=0) {
-		/* we hangup here, since our pipe is closed */
-		chan_misdn_log(2,tmp->bc->port,"misdn_read: Pipe closed, hanging up\n");
+	FD_ZERO(&rrfs);
+	FD_SET(tmp->pipe[0],&rrfs);
+
+	int t=select(FD_SETSIZE,&rrfs,NULL, NULL,&tv);
+
+	if (!t) {
+		chan_misdn_log(3, tmp->bc->port, "read Select Timed out\n");
+		len=160;
+	}
+
+	if (t<0) {
+		chan_misdn_log(-1, tmp->bc->port, "Select Error (err=%s)\n",strerror(errno));
+		return NULL;
+	}
+
+	if (FD_ISSET(tmp->pipe[0],&rrfs)) {
+		len=read(tmp->pipe[0],tmp->ast_rd_buf,sizeof(tmp->ast_rd_buf));
+
+		if (len<=0) {
+			/* we hangup here, since our pipe is closed */
+			chan_misdn_log(2,tmp->bc->port,"misdn_read: Pipe closed, hanging up\n");
+			return NULL;
+		}
+
+	} else {
 		return NULL;
 	}
 
@@ -4468,8 +4493,15 @@ cb_events(enum event_e event, struct misdn_bchannel *bc, void *user_data)
 			}
 		}
 	}
+	ch->l3id=bc->l3_id;
+	ch->addr=bc->addr;
+
+	start_bc_tones(ch);
 	
-	/* notice that we don't break here!*/
+	ch->state = MISDN_CONNECTED;
+	
+	ast_queue_control(ch->ast, AST_CONTROL_ANSWER);
+	break;
 	case EVENT_CONNECT_ACKNOWLEDGE:
 	{
 		ch->l3id=bc->l3_id;
@@ -4478,10 +4510,6 @@ cb_events(enum event_e event, struct misdn_bchannel *bc, void *user_data)
 		start_bc_tones(ch);
 		
 		ch->state = MISDN_CONNECTED;
-		
-		if (!ch->ast) break;
-
-		ast_queue_control(ch->ast, AST_CONTROL_ANSWER);
 	}
 	break;
 	case EVENT_DISCONNECT:
@@ -4541,9 +4569,6 @@ cb_events(enum event_e event, struct misdn_bchannel *bc, void *user_data)
 
 			hangup_chan(ch);
 			release_chan(bc);
-		
-			if (bc->need_release_complete) 
-				misdn_lib_send_event(bc,EVENT_RELEASE_COMPLETE);
 		}
 		break;
 	case EVENT_RELEASE_COMPLETE:

channels/misdn/isdn_lib.c

@@ -1566,9 +1566,6 @@ static int handle_event ( struct misdn_bchannel *bc, enum event_e event, iframe_
 		case EVENT_PROGRESS:
 		case EVENT_PROCEEDING:
 		case EVENT_SETUP_ACKNOWLEDGE:
-
-		setup_bc(bc);
-
 		case EVENT_SETUP:
 		{
 			if (bc->channel == 0xff || bc->channel<=0)
@@ -1580,6 +1577,8 @@ static int handle_event ( struct misdn_bchannel *bc, enum event_e event, iframe_
 				return -1;
 			}
 		}
+
+		setup_bc(bc);
 		break;
 
 		case EVENT_RELEASE_COMPLETE: