[Spice-commits] gtk/spice-channel.c

[Marc-André Lureau]

 gtk/spice-channel.c |   61 +++++++++++++++++++++++++++++++---------------------
 1 file changed, 37 insertions(+), 24 deletions(-)

New commits:
commit 951ab42743f24109994fe57dc1fb4b634d4fe435
Author: Marc-André Lureau <marcandre.lureau at redhat.com>
Date:   Tue Nov 27 20:17:13 2012 +0100

    channel: switch to protocol 1 on error during link-time
    
    The Spice server doesn't wait until all the data are received by the
    remote before closing the socket (that would need SO_LINGER?). Under
    some racy conditions, the client may not have received the link reply
    indicating the server protocol version mismatch, which would trigger
    reconnection with compatible protocol.
    
    It seems to happen on local networks with Windows sockets (error
    WSAECONNRESET). To workaround that issue, spice-gtk can try to
    reconnect with protocol 1 when a socket error is encoutered during
    link-time.
    
    Fixes:
    https://bugzilla.redhat.com/show_bug.cgi?id=874698

diff --git a/gtk/spice-channel.c b/gtk/spice-channel.c
index 6336485..369a0a5 100644
--- a/gtk/spice-channel.c
+++ b/gtk/spice-channel.c
@@ -1165,6 +1165,15 @@ static void spice_channel_send_link(SpiceChannel *channel)
     free(buffer);
 }
 
+static void spice_channel_switch_protocol(SpiceChannel *channel, gint version)
+{
+    SpiceChannelPrivate *c = channel->priv;
+
+    g_object_set(c->session, "protocol", version, NULL);
+    SPICE_CHANNEL_GET_CLASS(channel)->channel_disconnect(channel);
+    spice_channel_connect(channel);
+}
+
 /* coroutine context */
 static void spice_channel_recv_link_hdr(SpiceChannel *channel)
 {
@@ -1173,39 +1182,40 @@ static void spice_channel_recv_link_hdr(SpiceChannel *channel)
 
     rc = spice_channel_read(channel, &c->peer_hdr, sizeof(c->peer_hdr));
     if (rc != sizeof(c->peer_hdr)) {
-        g_critical("incomplete link header (%d/%" G_GSIZE_FORMAT ")",
-                   rc, sizeof(c->peer_hdr));
+        g_warning("incomplete link header (%d/%" G_GSIZE_FORMAT ")",
+                  rc, sizeof(c->peer_hdr));
         goto error;
     }
     if (c->peer_hdr.magic != SPICE_MAGIC) {
-        g_critical("invalid SPICE_MAGIC!");
+        g_warning("invalid SPICE_MAGIC!");
         goto error;
     }
 
     CHANNEL_DEBUG(channel, "Peer version: %d:%d", c->peer_hdr.major_version, c->peer_hdr.minor_version);
     if (c->peer_hdr.major_version != c->link_hdr.major_version) {
-        if (c->peer_hdr.major_version == 1) {
-            /* enter spice 0.4 mode */
-            g_object_set(c->session, "protocol", 1, NULL);
-            CHANNEL_DEBUG(channel, "switching to protocol 1 (spice 0.4)");
-            SPICE_CHANNEL_GET_CLASS(channel)->channel_disconnect(channel);
-            spice_channel_connect(channel);
-            return;
-        }
-        g_critical("major mismatch (got %d, expected %d)",
-                   c->peer_hdr.major_version, c->link_hdr.major_version);
+        g_warning("major mismatch (got %d, expected %d)",
+                  c->peer_hdr.major_version, c->link_hdr.major_version);
         goto error;
     }
 
     c->peer_msg = spice_malloc(c->peer_hdr.size);
     if (c->peer_msg == NULL) {
-        g_critical("invalid peer header size: %u", c->peer_hdr.size);
+        g_warning("invalid peer header size: %u", c->peer_hdr.size);
         goto error;
     }
 
     return;
 
 error:
+    /* Windows socket seems to give early CONNRESET errors. The server
+       does not linger when closing the socket if the protocol is
+       incompatible. Try with the oldest protocol in this case: */
+    if (c->link_hdr.major_version != 1) {
+        SPICE_DEBUG("%s: error, switching to protocol 1 (spice 0.4)", c->name);
+        spice_channel_switch_protocol(channel, 1);
+        return;
+    }
+
     emit_main_context(channel, SPICE_CHANNEL_EVENT, SPICE_CHANNEL_ERROR_LINK);
 }
 
@@ -2060,8 +2070,19 @@ static gboolean spice_channel_iterate(SpiceChannel *channel)
 #endif
     } while (ret == 0); /* ret == 0 means no IO condition, but woken up */
 
-    if (ret & (G_IO_ERR|G_IO_HUP)) {
-        CHANNEL_DEBUG(channel, "got socket error before read(): %d", ret);
+    if (ret & G_IO_IN) {
+        do
+            SPICE_CHANNEL_GET_CLASS(channel)->iterate_read(channel);
+#if HAVE_SASL
+        while (c->sasl_decoded != NULL);
+#else
+        while (FALSE);
+#endif
+    }
+
+    if (c->state > SPICE_CHANNEL_STATE_CONNECTING &&
+        ret & (G_IO_ERR|G_IO_HUP)) {
+        SPICE_DEBUG("got socket error: %d", ret);
         emit_main_context(channel, SPICE_CHANNEL_EVENT,
                           c->state == SPICE_CHANNEL_STATE_READY ?
                           SPICE_CHANNEL_ERROR_IO : SPICE_CHANNEL_ERROR_LINK);
@@ -2069,14 +2090,6 @@ static gboolean spice_channel_iterate(SpiceChannel *channel)
         return FALSE;
     }
 
-    do
-        SPICE_CHANNEL_GET_CLASS(channel)->iterate_read(channel);
-#if HAVE_SASL
-    while (c->sasl_decoded != NULL);
-#else
-    while (FALSE);
-#endif
-
     return TRUE;
 }