Changeset d493830e in mainline

Timestamp:

2010-12-27T19:16:47Z (14 years ago)

Author:

Jiri Svoboda <jiri@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

727f04f

Parents:

58fe0aa

Message:

Fix incoming TCP FIN handling. Signal end of data on the socket. Do not ACK if no new data arrived.

Location:

uspace

Files:

• lib/c/generic/net/socket_client.c (modified) (3 diffs)
• srv/net/tl/tcp/tcp.c (modified) (7 diffs)

uspace/lib/c/generic/net/socket_client.c

@@ -1006 +1006 @@
         // wait for a received packet
         ++socket->blocked;
-        while ((result = dyn_fifo_value(&socket->received)) <= 0) {
+        while ((result = dyn_fifo_value(&socket->received)) < 0) {
                 fibril_rwlock_read_unlock(&socket_globals.lock);
                 fibril_condvar_wait(&socket->receive_signal,
@@ -1018 +1018 @@
         --socket->blocked;
         fragments = (size_t) result;
+
+        if (fragments == 0) {
+                /* No more data, other side has closed the connection. */
+                return 0;
+        }
 
         // prepare lengths if more fragments
@@ -1057 +1062 @@
 
                 free(lengths);
-        } else {
+        } else { /* fragments == 1 */
                 // request packet data
                 message_id = async_send_4(socket->phone, message,

uspace/srv/net/tl/tcp/tcp.c

@@ -205 +205 @@
 static int tcp_queue_received_packet(socket_core_t *, tcp_socket_data_t *,
     packet_t *, int, size_t);
+static void tcp_queue_received_end_of_data(socket_core_t *socket);
 
 static int tcp_received_msg(device_id_t, packet_t *, services_t, services_t);
@@ -504 +505 @@
         size_t offset;
         uint32_t new_sequence_number;
+        bool forced_ack;
         int rc;
 
@@ -512 +514 @@
         assert(packet);
 
+        forced_ack = false;
+
         new_sequence_number = ntohl(header->sequence_number);
         old_incoming = socket_data->next_incoming;
 
-        if (header->finalize)
-                socket_data->fin_incoming = new_sequence_number;
+        if (header->finalize) {
+                socket_data->fin_incoming = new_sequence_number +
+                    total_length - TCP_HEADER_LENGTH(header);
+        }
 
         /* Trim begining if containing expected data */
@@ -760 +766 @@
                 /* Release duplicite or restricted */
                 pq_release_remote(tcp_globals.net_phone, packet_get_id(packet));
-        }
-
-        /* Change state according to the acknowledging incoming fin */
-        if (IS_IN_INTERVAL_OVERFLOW(old_incoming, socket_data->fin_incoming,
-            socket_data->next_incoming)) {
+                forced_ack = true;
+        }
+
+        if (header->finalize)
+                socket_data->next_incoming += 1;
+
+        /* If next in sequence is an incoming FIN */
+        if (socket_data->next_incoming == socket_data->fin_incoming) {
+                /* Advance sequence number */
+                socket_data->next_incoming += 1;
+
+                /* Handle FIN */
                 switch (socket_data->state) {
                 case TCP_SOCKET_FIN_WAIT_1:
@@ -771 +784 @@
                         socket_data->state = TCP_SOCKET_CLOSING;
                         break;
-                /*case TCP_ESTABLISHED:*/
+                case TCP_SOCKET_ESTABLISHED:
+                        /* Queue end-of-data marker on the socket. */
+                        tcp_queue_received_end_of_data(socket);
+                        socket_data->state = TCP_SOCKET_CLOSE_WAIT;
+                        break;
                 default:
                         socket_data->state = TCP_SOCKET_CLOSE_WAIT;
@@ -779 +796 @@
 
         packet = tcp_get_packets_to_send(socket, socket_data);
-        if (!packet) {
+        if (!packet && (socket_data->next_incoming != old_incoming || forced_ack)) {
                 /* Create the notification packet */
                 rc = tcp_create_notification_packet(&packet, socket,
@@ -835 +852 @@
 
         return EOK;
+}
+
+/** Queue end-of-data marker on the socket.
+ *
+ * Next element in the sequence space is FIN. Queue end-of-data marker
+ * on the socket.
+ *
+ * @param socket        Socket
+ */
+static void tcp_queue_received_end_of_data(socket_core_t *socket)
+{
+        assert(socket != NULL);
+
+        /* Notify the destination socket */
+        async_msg_5(socket->phone, NET_SOCKET_RECEIVED,
+            (sysarg_t) socket->socket_id,
+            0, 0, 0,
+            (sysarg_t) 0 /* 0 fragments == no more data */);
 }