[GNUnet-SVN] r37093 - in branches/mhd-0.9.50: . src/microhttpd

[gnunet]

Author: Karlson2k
Date: 2016-04-29 23:14:23 +0200 (Fri, 29 Apr 2016)
New Revision: 37093

Modified:
   branches/mhd-0.9.50/ChangeLog
   branches/mhd-0.9.50/src/microhttpd/daemon.c
Log:
Fixed rare situations when suspended connection can't be resumed.

Modified: branches/mhd-0.9.50/ChangeLog
===================================================================
--- branches/mhd-0.9.50/ChangeLog       2016-04-29 21:14:21 UTC (rev 37092)
+++ branches/mhd-0.9.50/ChangeLog       2016-04-29 21:14:23 UTC (rev 37093)
@@ -1,3 +1,9 @@
+Mon Apr 18 19:35:14 CET 2016
+       Fixed handling of MHD_OPTION_THREAD_POOL_SIZE with
+       MHD_USE_SUSPEND_RESUME (regression in 0.9.49).
+       Fixed data races leading to inability in rare situations to
+       resume suspended connection. -EG
+
 Tue Apr 13 21:46:01 CET 2016
        Ignored specific errors in 'test_post' test until libcurl
        will implement workaround for WinSock bug.

Modified: branches/mhd-0.9.50/src/microhttpd/daemon.c
===================================================================
--- branches/mhd-0.9.50/src/microhttpd/daemon.c 2016-04-29 21:14:21 UTC (rev 
37092)
+++ branches/mhd-0.9.50/src/microhttpd/daemon.c 2016-04-29 21:14:23 UTC (rev 
37093)
@@ -958,7 +958,7 @@
              break;
            }
 #if WINDOWS
-          /* drain signaling pipe */
+          /* drain signaling pipe before other processing */
           if ( (MHD_INVALID_PIPE_ != spipe) &&
                (FD_ISSET (spipe, &rs)) )
             MHD_pipe_drain_ (spipe);
@@ -1030,7 +1030,7 @@
              break;
            }
 #if WINDOWS
-          /* drain signaling pipe */
+          /* drain signaling pipe before other processing */
           if ( (MHD_INVALID_PIPE_ != spipe) &&
                (0 != (p[1].revents & (POLLERR | POLLHUP))) )
             MHD_pipe_drain_ (spipe);
@@ -1811,9 +1811,11 @@
   if ( (0 != (daemon->options & MHD_USE_THREAD_PER_CONNECTION)) &&
        (MHD_YES != MHD_mutex_lock_ (&daemon->cleanup_connection_mutex)) )
     MHD_PANIC ("Failed to acquire cleanup mutex\n");
-  if (MHD_YES == daemon->resuming)
+  if (MHD_NO != daemon->resuming)
     next = daemon->suspended_connections_head;
-
+ 
+  if (NULL != next)
+    daemon->resuming = MHD_NO;
   while (NULL != (pos = next))
     {
       next = pos->next;
@@ -1851,7 +1853,6 @@
       pos->suspended = MHD_NO;
       pos->resuming = MHD_NO;
     }
-  daemon->resuming = MHD_NO;
   if ( (0 != (daemon->options & MHD_USE_THREAD_PER_CONNECTION)) &&
        (MHD_YES != MHD_mutex_unlock_ (&daemon->cleanup_connection_mutex)) )
     MHD_PANIC ("Failed to release cleanup mutex\n");
@@ -2249,6 +2250,13 @@
   unsigned int mask = MHD_USE_SUSPEND_RESUME | 
MHD_USE_EPOLL_INTERNALLY_LINUX_ONLY |
     MHD_USE_SELECT_INTERNALLY | MHD_USE_POLL_INTERNALLY | 
MHD_USE_THREAD_PER_CONNECTION;
 
+  /* drain signaling pipe to avoid spinning select */
+  /* Do it before any other processing so new signals
+     will trigger select again and will be processed */
+  if ((MHD_INVALID_PIPE_ != daemon->wpipe[0]) &&
+      (FD_ISSET (daemon->wpipe[0], read_fd_set)))
+    MHD_pipe_drain_ (daemon->wpipe[0]);
+
   /* Resuming external connections when using an extern mainloop  */
   if (MHD_USE_SUSPEND_RESUME == (daemon->options & mask))
     resume_suspended_connections (daemon);
@@ -2270,10 +2278,6 @@
   if ( (MHD_INVALID_SOCKET != (ds = daemon->socket_fd)) &&
        (FD_ISSET (ds, read_fd_set)) )
     (void) MHD_accept_connection (daemon);
-  /* drain signaling pipe to avoid spinning select */
-  if ( (MHD_INVALID_PIPE_ != daemon->wpipe[0]) &&
-       (FD_ISSET (daemon->wpipe[0], read_fd_set)) )
-    MHD_pipe_drain_ (daemon->wpipe[0]);
 
   if (0 == (daemon->options & MHD_USE_THREAD_PER_CONNECTION))
     {
@@ -2578,6 +2582,13 @@
         free(p);
        return MHD_NO;
       }
+    /* handle pipe FD */
+    /* do it before any other processing so
+       new signals will be processed in next loop */
+    if ( (-1 != poll_pipe) &&
+         (0 != (p[poll_pipe].revents & POLLIN)) )
+      MHD_pipe_drain_ (daemon->wpipe[0]);
+
     /* handle shutdown */
     if (MHD_YES == daemon->shutdown)
       {
@@ -2632,11 +2643,6 @@
         (0 != (p[poll_listen].revents & POLLIN)) )
       (void) MHD_accept_connection (daemon);
 
-    /* handle pipe FD */
-    if ( (-1 != poll_pipe) &&
-         (0 != (p[poll_pipe].revents & POLLIN)) )
-      MHD_pipe_drain_ (daemon->wpipe[0]);
-
     free(p);
   }
   return MHD_YES;
@@ -2844,6 +2850,8 @@
           if ( (MHD_INVALID_PIPE_ != daemon->wpipe[0]) &&
                (daemon->wpipe[0] == events[i].data.fd) )
             {
+              /* It's OK to drain pipe here as all external
+                 conditions will be processed later. */
               MHD_pipe_drain_ (daemon->wpipe[0]);
               continue;
             }