glib: Add GSocket patch for race condition on Windows

https://bugzilla.gnome.org/show_bug.cgi?id=762283

1 files changed, 309 insertions, 0 deletions

diff --git a/recipes/glib/0017-GSocket-Fix-race-conditions-on-Win32-if-multiple-thr.patch b/recipes/glib/0017-GSocket-Fix-race-conditions-on-Win32-if-multiple-thr.patch
new file mode 100644
index 00000000..8634baca
--- /dev/null
+++ b/recipes/glib/0017-GSocket-Fix-race-conditions-on-Win32-if-multiple-thr.patch
@@ -0,0 +1,309 @@
+From e5ae075ff9b3cba2ee7b7393bc7f4b49c3d3ee79 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Sebastian=20Dr=C3=B6ge?= <sebastian@centricular.com>
+Date: Mon, 5 Dec 2016 12:28:57 +0200
+Subject: [PATCH] GSocket: Fix race conditions on Win32 if multiple threads are
+ waiting on conditions for the same socket
+
+WSAWaitForMultipleEvents() only returns for one of the waiting threads, and
+that one might not even be the one waiting for the condition that changed. As
+such, only let a single thread wait on the event and use a GCond for all other
+threads.
+
+With this it is possible to e.g. have an UDP socket that is written to from
+one thread and read from in another thread on Win32 too. On POSIX systems this
+was working before already.
+
+https://bugzilla.gnome.org/show_bug.cgi?id=762283
+---
+ gio/gsocket.c | 94 ++++++++++++++++++++++++++++++++++++++++++-----------------
+ 1 file changed, 68 insertions(+), 26 deletions(-)
+
+diff --git a/gio/gsocket.c b/gio/gsocket.c
+index 5a2f33285..ff5403b6f 100644
+--- a/gio/gsocket.c
++++ b/gio/gsocket.c
+@@ -249,11 +249,14 @@ struct _GSocketPrivate
+   guint           connect_pending : 1;
+ #ifdef G_OS_WIN32
+   WSAEVENT        event;
++  gboolean        waiting;
++  DWORD           waiting_result;
+   int             current_events;
+   int             current_errors;
+   int             selected_events;
+   GList          *requested_conditions; /* list of requested GIOCondition * */
+   GMutex          win32_source_lock;
++  GCond           win32_source_cond;
+ #endif
+ 
+   struct {
+@@ -333,8 +336,10 @@ socket_strerror (int err)
+ static void
+ _win32_unset_event_mask (GSocket *socket, int mask)
+ {
++  g_mutex_lock (&socket->priv->win32_source_lock);
+   socket->priv->current_events &= ~mask;
+   socket->priv->current_errors &= ~mask;
++  g_mutex_unlock (&socket->priv->win32_source_lock);
+ }
+ #else
+ #define win32_unset_event_mask(_socket, _mask)
+@@ -831,6 +836,7 @@ g_socket_finalize (GObject *object)
+ 
+   g_assert (socket->priv->requested_conditions == NULL);
+   g_mutex_clear (&socket->priv->win32_source_lock);
++  g_cond_clear (&socket->priv->win32_source_cond);
+ #endif
+ 
+   for (i = 0; i < RECV_ADDR_CACHE_SIZE; i++)
+@@ -1058,6 +1064,7 @@ g_socket_init (GSocket *socket)
+ #ifdef G_OS_WIN32
+   socket->priv->event = WSA_INVALID_EVENT;
+   g_mutex_init (&socket->priv->win32_source_lock);
++  g_cond_init (&socket->priv->win32_source_cond);
+ #endif
+ }
+ 
+@@ -2441,6 +2448,8 @@ g_socket_accept (GSocket       *socket,
+ 
+   while (TRUE)
+     {
++      win32_unset_event_mask (socket, FD_ACCEPT);
++
+       if ((ret = accept (socket->priv->fd, NULL, 0)) < 0)
+ 	{
+ 	  int errsv = get_socket_errno ();
+@@ -2455,8 +2464,6 @@ g_socket_accept (GSocket       *socket,
+               errsv == EAGAIN)
+ #endif
+             {
+-              win32_unset_event_mask (socket, FD_ACCEPT);
+-
+               if (socket->priv->blocking)
+                 {
+                   if (!g_socket_condition_wait (socket,
+@@ -2473,8 +2480,6 @@ g_socket_accept (GSocket       *socket,
+       break;
+     }
+ 
+-  win32_unset_event_mask (socket, FD_ACCEPT);
+-
+ #ifdef G_OS_WIN32
+   {
+     /* The socket inherits the accepting sockets event mask and even object,
+@@ -2563,6 +2568,8 @@ g_socket_connect (GSocket         *socket,
+ 
+   while (1)
+     {
++      win32_unset_event_mask (socket, FD_CONNECT);
++
+       if (connect (socket->priv->fd, (struct sockaddr *) &buffer,
+ 		   g_socket_address_get_native_size (address)) < 0)
+ 	{
+@@ -2577,8 +2584,6 @@ g_socket_connect (GSocket         *socket,
+ 	  if (errsv == WSAEWOULDBLOCK)
+ #endif
+ 	    {
+-              win32_unset_event_mask (socket, FD_CONNECT);
+-
+ 	      if (socket->priv->blocking)
+ 		{
+ 		  if (g_socket_condition_wait (socket, G_IO_OUT, cancellable, error))
+@@ -2604,8 +2609,6 @@ g_socket_connect (GSocket         *socket,
+       break;
+     }
+ 
+-  win32_unset_event_mask (socket, FD_CONNECT);
+-
+   socket->priv->connected_read = TRUE;
+   socket->priv->connected_write = TRUE;
+ 
+@@ -2785,6 +2788,8 @@ g_socket_receive_with_timeout (GSocket       *socket,
+ 
+   while (1)
+     {
++      win32_unset_event_mask (socket, FD_READ);
++
+       if ((ret = recv (socket->priv->fd, buffer, size, 0)) < 0)
+ 	{
+ 	  int errsv = get_socket_errno ();
+@@ -2799,8 +2804,6 @@ g_socket_receive_with_timeout (GSocket       *socket,
+               errsv == EAGAIN)
+ #endif
+             {
+-              win32_unset_event_mask (socket, FD_READ);
+-
+               if (timeout != 0)
+                 {
+                   if (!block_on_timeout (socket, G_IO_IN, timeout, start_time,
+@@ -2811,14 +2814,10 @@ g_socket_receive_with_timeout (GSocket       *socket,
+                 }
+             }
+ 
+-	  win32_unset_event_mask (socket, FD_READ);
+-
+ 	  socket_set_error_lazy (error, errsv, _("Error receiving data: %s"));
+ 	  return -1;
+ 	}
+ 
+-      win32_unset_event_mask (socket, FD_READ);
+-
+       break;
+     }
+ 
+@@ -2984,6 +2983,8 @@ g_socket_send_with_timeout (GSocket       *socket,
+ 
+   while (1)
+     {
++      win32_unset_event_mask (socket, FD_WRITE);
++
+       if ((ret = send (socket->priv->fd, buffer, size, G_SOCKET_DEFAULT_SEND_FLAGS)) < 0)
+ 	{
+ 	  int errsv = get_socket_errno ();
+@@ -2998,8 +2999,6 @@ g_socket_send_with_timeout (GSocket       *socket,
+               errsv == EAGAIN)
+ #endif
+             {
+-              win32_unset_event_mask (socket, FD_WRITE);
+-
+               if (timeout != 0)
+                 {
+                   if (!block_on_timeout (socket, G_IO_OUT, timeout, start_time,
+@@ -3414,7 +3413,7 @@ remove_condition_watch (GSocket      *socket,
+ }
+ 
+ static GIOCondition
+-update_condition (GSocket *socket)
++update_condition_unlocked (GSocket *socket)
+ {
+   WSANETWORKEVENTS events;
+   GIOCondition condition;
+@@ -3481,6 +3480,16 @@ update_condition (GSocket *socket)
+ 
+   return condition;
+ }
++
++static GIOCondition
++update_condition (GSocket *socket)
++{
++  GIOCondition res;
++  g_mutex_lock (&socket->priv->win32_source_lock);
++  res = update_condition_unlocked (socket);
++  g_mutex_unlock (&socket->priv->win32_source_lock);
++  return res;
++}
+ #endif
+ 
+ typedef struct {
+@@ -3876,11 +3885,44 @@ g_socket_condition_timed_wait (GSocket       *socket,
+     if (timeout == -1)
+       timeout = WSA_INFINITE;
+ 
+-    current_condition = update_condition (socket);
++    g_mutex_lock (&socket->priv->win32_source_lock);
++    current_condition = update_condition_unlocked (socket);
+     while ((condition & current_condition) == 0)
+       {
+-	res = WSAWaitForMultipleEvents (num_events, events,
+-					FALSE, timeout, FALSE);
++        if (!socket->priv->waiting)
++          {
++            socket->priv->waiting = TRUE;
++            socket->priv->waiting_result = 0;
++            g_mutex_unlock (&socket->priv->win32_source_lock);
++
++            res = WSAWaitForMultipleEvents (num_events, events, FALSE, timeout, FALSE);
++
++            g_mutex_lock (&socket->priv->win32_source_lock);
++            socket->priv->waiting = FALSE;
++            socket->priv->waiting_result = res;
++            g_cond_broadcast (&socket->priv->win32_source_cond);
++          }
++        else
++          {
++            if (timeout != WSA_INFINITE)
++              {
++                if (!g_cond_wait_until (&socket->priv->win32_source_cond, &socket->priv->win32_source_lock, timeout))
++                  {
++                    res = WSA_WAIT_TIMEOUT;
++                    break;
++                  }
++                else
++                  {
++                    res = socket->priv->waiting_result;
++                  }
++              }
++            else
++              {
++                g_cond_wait (&socket->priv->win32_source_cond, &socket->priv->win32_source_lock);
++                res = socket->priv->waiting_result;
++              }
++          }
++
+ 	if (res == WSA_WAIT_FAILED)
+ 	  {
+ 	    int errsv = get_socket_errno ();
+@@ -3901,7 +3943,7 @@ g_socket_condition_timed_wait (GSocket       *socket,
+ 	if (g_cancellable_set_error_if_cancelled (cancellable, error))
+ 	  break;
+ 
+-	current_condition = update_condition (socket);
++        current_condition = update_condition_unlocked (socket);
+ 
+ 	if (timeout != WSA_INFINITE)
+ 	  {
+@@ -3910,6 +3952,7 @@ g_socket_condition_timed_wait (GSocket       *socket,
+ 	      timeout = 0;
+ 	  }
+       }
++    g_mutex_unlock (&socket->priv->win32_source_lock);
+     remove_condition_watch (socket, &condition);
+     if (num_events > 1)
+       g_cancellable_release_fd (cancellable);
+@@ -4405,6 +4448,8 @@ g_socket_send_message_with_timeout (GSocket                *socket,
+ 
+     while (1)
+       {
++        win32_unset_event_mask (socket, FD_WRITE);
++
+ 	if (address)
+ 	  result = WSASendTo (socket->priv->fd,
+ 			      bufs, num_vectors,
+@@ -4426,8 +4471,6 @@ g_socket_send_message_with_timeout (GSocket                *socket,
+ 
+ 	    if (errsv == WSAEWOULDBLOCK)
+               {
+-                win32_unset_event_mask (socket, FD_WRITE);
+-
+                 if (timeout != 0)
+                   {
+                     if (!block_on_timeout (socket, G_IO_OUT, timeout,
+@@ -4875,6 +4918,8 @@ g_socket_receive_message_with_timeout (GSocket                 *socket,
+     /* do it */
+     while (1)
+       {
++        win32_unset_event_mask (socket, FD_READ);
++
+ 	addrlen = sizeof addr;
+ 	if (address)
+ 	  result = WSARecvFrom (socket->priv->fd,
+@@ -4896,8 +4941,6 @@ g_socket_receive_message_with_timeout (GSocket                 *socket,
+ 
+             if (errsv == WSAEWOULDBLOCK)
+               {
+-                win32_unset_event_mask (socket, FD_READ);
+-
+                 if (timeout != 0)
+                   {
+                     if (!block_on_timeout (socket, G_IO_IN, timeout,
+@@ -4911,7 +4954,6 @@ g_socket_receive_message_with_timeout (GSocket                 *socket,
+ 	    socket_set_error_lazy (error, errsv, _("Error receiving message: %s"));
+ 	    return -1;
+ 	  }
+-	win32_unset_event_mask (socket, FD_READ);
+ 	break;
+       }
+ 
+-- 
+2.11.0
+