If a full frame is received while one of the iax2 threads is in the middle

of handling a full frame for the same call, queue it up for processing by that
same thread later instead of dropping it.
(issue #9937, patch by me)


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@70866 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_iax2.c

@@ -682,6 +682,12 @@ static int ast_cli_netstats(struct mansession *s, int fd, int limit_fmt);
 #define IAX_TYPE_POOL    1
 #define IAX_TYPE_DYNAMIC 2
 
+struct iax2_pkt_buf {
+	AST_LIST_ENTRY(iax2_pkt_buf) entry;
+	size_t len;
+	unsigned char buf[1];
+};
+
 struct iax2_thread {
 	AST_LIST_ENTRY(iax2_thread) list;
 	int type;
@@ -697,8 +703,10 @@ struct iax2_thread {
 	pthread_t threadid;
 	int threadnum;
 	struct sockaddr_in iosin;
-	unsigned char buf[4096]; 
-	int iores;
+	unsigned char readbuf[4096]; 
+	unsigned char *buf;
+	size_t buf_len;
+	size_t buf_size;
 	int iofd;
 	time_t checktime;
 	ast_mutex_t lock;
@@ -713,6 +721,10 @@ struct iax2_thread {
 		unsigned char type;
 		unsigned char csub;
 	} ffinfo;
+	/*! Queued up full frames for processing.  If more full frames arrive for
+	 *  a call which this thread is already processing a full frame for, they
+	 *  are queued up here. */
+	AST_LIST_HEAD_NOLOCK(, iax2_pkt_buf) full_frames;
 };
 
 /* Thread lists */
@@ -6272,6 +6284,69 @@ static void save_rr(struct iax_frame *fr, struct iax_ies *ies)
 	iaxs[fr->callno]->remote_rr.ooo = ies->rr_ooo;
 }
 
+static int socket_process(struct iax2_thread *thread);
+
+/*!
+ * \brief Handle any deferred full frames for this thread
+ */
+static void handle_deferred_full_frames(struct iax2_thread *thread)
+{
+	struct iax2_pkt_buf *pkt_buf;
+
+	ast_mutex_lock(&thread->lock);
+
+	while ((pkt_buf = AST_LIST_REMOVE_HEAD(&thread->full_frames, entry))) {
+		ast_mutex_unlock(&thread->lock);
+
+		thread->buf = pkt_buf->buf;
+		thread->buf_len = pkt_buf->len;
+		thread->buf_size = pkt_buf->len + 1;
+		
+		socket_process(thread);
+
+		thread->buf = NULL;
+		ast_free(pkt_buf);
+
+		ast_mutex_lock(&thread->lock);
+	}
+
+	ast_mutex_unlock(&thread->lock);
+}
+
+/*!
+ * \brief Queue the last read full frame for processing by a certain thread
+ *
+ * If there are already any full frames queued, they are sorted
+ * by sequence number.
+ */
+static void defer_full_frame(struct iax2_thread *thread)
+{
+	struct iax2_pkt_buf *pkt_buf, *cur_pkt_buf;
+	struct ast_iax2_full_hdr *fh, *cur_fh;
+
+	if (!(pkt_buf = ast_calloc(1, sizeof(*pkt_buf) + thread->buf_len)))
+		return;
+
+	pkt_buf->len = thread->buf_len;
+	memcpy(pkt_buf->buf, thread->buf, pkt_buf->len);
+
+	fh = (struct ast_iax2_full_hdr *) pkt_buf->buf;
+	ast_mutex_lock(&thread->lock);
+	AST_LIST_TRAVERSE_SAFE_BEGIN(&thread->full_frames, cur_pkt_buf, entry) {
+		cur_fh = (struct ast_iax2_full_hdr *) cur_pkt_buf->buf;
+		if (fh->oseqno < cur_fh->oseqno) {
+			AST_LIST_INSERT_BEFORE_CURRENT(&thread->full_frames, pkt_buf, entry);
+			break;
+		}
+	}
+	AST_LIST_TRAVERSE_SAFE_END
+
+	if (!cur_pkt_buf)
+		AST_LIST_INSERT_TAIL(&thread->full_frames, pkt_buf, entry);
+	
+	ast_mutex_unlock(&thread->lock);
+}
+
 static int socket_read(int *id, int fd, short events, void *cbdata)
 {
 	struct iax2_thread *thread;
@@ -6291,8 +6366,10 @@ static int socket_read(int *id, int fd, short events, void *cbdata)
 
 	len = sizeof(thread->iosin);
 	thread->iofd = fd;
-	thread->iores = recvfrom(fd, thread->buf, sizeof(thread->buf), 0, (struct sockaddr *) &thread->iosin, &len);
-	if (thread->iores < 0) {
+	thread->buf_len = recvfrom(fd, thread->readbuf, sizeof(thread->buf), 0, (struct sockaddr *) &thread->iosin, &len);
+	thread->buf_size = sizeof(thread->readbuf);
+	thread->buf = thread->readbuf;
+	if (thread->buf_len < 0) {
 		if (errno != ECONNREFUSED && errno != EAGAIN)
 			ast_log(LOG_WARNING, "Error: %s\n", strerror(errno));
 		handle_error();
@@ -6317,16 +6394,11 @@ static int socket_read(int *id, int fd, short events, void *cbdata)
 			    !inaddrcmp(&cur->ffinfo.sin, &thread->iosin))
 				break;
 		}
-		AST_LIST_UNLOCK(&active_list);
 		if (cur) {
 			/* we found another thread processing a full frame for this call,
-			   so we can't accept this frame */
-			if (option_debug)
-				ast_log(LOG_DEBUG, "Dropping frame from %s (callno %d) of type %d (subclass %d) due to frame of type %d (subclass %d) already in process\n",
-				ast_inet_ntoa(thread->iosin.sin_addr), cur->ffinfo.callno,
-				fh->type, uncompress_subclass(fh->csub),
-				cur->ffinfo.type, uncompress_subclass(cur->ffinfo.csub));
-			insert_idle_thread(thread);
+			   so queue it up for processing later. */
+			defer_full_frame(thread);
+			AST_LIST_UNLOCK(&active_list);
 			return 1;
 		} else {
 			/* this thread is going to process this frame, so mark it */
@@ -6335,6 +6407,7 @@ static int socket_read(int *id, int fd, short events, void *cbdata)
 			thread->ffinfo.type = fh->type;
 			thread->ffinfo.csub = fh->csub;
 		}
+		AST_LIST_UNLOCK(&active_list);
 	}
 	
 	/* Mark as ready and send on its way */
@@ -6389,7 +6462,7 @@ static int socket_process(struct iax2_thread *thread)
 	fr->callno = 0;
 
 	/* Copy frequently used parameters to the stack */
-	res = thread->iores;
+	res = thread->buf_len;
 	fd = thread->iofd;
 	memcpy(&sin, &thread->iosin, sizeof(sin));
 
@@ -6671,7 +6744,7 @@ static int socket_process(struct iax2_thread *thread)
 		}
 		/* Ensure text frames are NULL-terminated */
 		if (f.frametype == AST_FRAME_TEXT && thread->buf[res - 1] != '\0') {
-			if (res < sizeof(thread->buf))
+			if (res < thread->buf_size)
 				thread->buf[res++] = '\0';
 			else /* Trims one character from the text message, but that's better than overwriting the end of the buffer. */
 				thread->buf[res - 1] = '\0';
@@ -7807,6 +7880,7 @@ static void *iax2_process_thread(void *data)
 			thread->actions++;
 			thread->iostate = IAX_IOSTATE_PROCESSING;
 			socket_process(thread);
+			handle_deferred_full_frames(thread);
 			break;
 		case IAX_IOSTATE_SCHEDREADY:
 			thread->actions++;
@@ -7827,6 +7901,9 @@ static void *iax2_process_thread(void *data)
 		AST_LIST_REMOVE(&active_list, thread, list);
 		AST_LIST_UNLOCK(&active_list);
 
+		/* Make sure another frame didn't sneak in there after we thought we were done. */
+		handle_deferred_full_frames(thread);
+
 		/* Go back into our respective list */
 		put_into_idle = 1;
 	}