Thu Aug 3 21:49:27 UTC 2006 Carlos O'Ryan <coryan@atdesk.com>fix_bug_2540

3 files changed, 30 insertions, 6 deletions

diff --git a/ChangeLog b/ChangeLog
index 436605b25ba..b361d555dad 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+Thu Aug  3 21:49:27 UTC 2006  Carlos O'Ryan  <coryan@atdesk.com>
+
+        * ace/TP_Reactor.cpp:
+        * ace/Select_Reactor_T.cpp:
+          Avoid the problems described in bug 2540 by detecting the
+          infinite loop and recomputing the number of active handlers.
+          Thanks to Jody Hagins for correcting my original "fix."
+
 Thu Aug  3 10:39:12 UTC 2006  Johnny Willemsen  <jwillemsen@remedy.nl>
 
         * ace/Connector.h:
diff --git a/ace/Select_Reactor_T.cpp b/ace/Select_Reactor_T.cpp
index 1dd2fc26b2a..50c9eec5dc1 100644
--- a/ace/Select_Reactor_T.cpp
+++ b/ace/Select_Reactor_T.cpp
@@ -1286,6 +1286,13 @@ ACE_Select_Reactor_T<ACE_SELECT_REACTOR_TOKEN>::dispatch
 
   do
     {
+      // We expect that the loop will decrease the number of active
+      // handles in each iteration.  If it does not, then something is
+      // inconsistent in the state of the Reactor and we should avoid
+      // the loop.  Please read the comments on bug 2540 for more
+      // details.
+      int initial_handle_count = active_handle_count;
+
       // Note that we keep track of changes to our state.  If any of
       // the dispatch_*() methods below return -1 it means that the
       // <wait_set_> state has changed as the result of an
@@ -1360,11 +1367,10 @@ ACE_Select_Reactor_T<ACE_SELECT_REACTOR_TOKEN>::dispatch
 
       // if state changed, we need to re-eval active_handle_count,
       // so we will not end with an endless loop
-      if (this->state_changed_)
+      if (initial_handle_count == active_handle_count
+          || this->state_changed_)
       {
-          active_handle_count = this->dispatch_set_.rd_mask_.num_set ()
-              + this->dispatch_set_.wr_mask_.num_set ()
-              + this->dispatch_set_.ex_mask_.num_set ();
+        active_handle_count = this->any_ready (dispatch_set);
       }
     }
   while (active_handle_count > 0);
diff --git a/ace/TP_Reactor.cpp b/ace/TP_Reactor.cpp
index 1207cd7c93b..6773bf72ada 100644
--- a/ace/TP_Reactor.cpp
+++ b/ace/TP_Reactor.cpp
@@ -255,6 +255,10 @@ ACE_TP_Reactor::dispatch_i (ACE_Time_Value *max_wait_time,
   int event_count =
     this->get_event_for_dispatching (max_wait_time);
 
+  // We use this count to detect potential infinite loops as described
+  // in bug 2540.
+  int initial_event_count = event_count;
+
   int result = 0;
 
   // Note: We are passing the <event_count> around, to have record of
@@ -310,8 +314,14 @@ ACE_TP_Reactor::dispatch_i (ACE_Time_Value *max_wait_time,
   if (event_count > 0)
     {
       // Handle socket events
-      return this->handle_socket_events (event_count,
-                                         guard);
+      result = this->handle_socket_events (event_count,
+                                           guard);
+    }
+
+  if (event_count != 0
+      && event_count == initial_event_count)
+    {
+      this->state_changed_ = true;
     }
 
   return 0;