ChangeLogTag: Tue Aug 27 18:31:53 2002 Balachandran Natarajan <bala@isis-server.vuse.vanderbilt.edu>

4 files changed, 46 insertions, 35 deletions

diff --git a/TAO/ChangeLog b/TAO/ChangeLog
index dba79fa12b7..c0d539670cd 100644
--- a/TAO/ChangeLog
+++ b/TAO/ChangeLog
@@ -1,3 +1,19 @@
+Tue Aug 27 18:31:53 2002  Balachandran Natarajan  <bala@isis-server.vuse.vanderbilt.edu>
+
+	* tao/Transport.cpp: Made the methods purge_entry () and make_idle 
+	  () more readable. Instead of checking whether the hash_map entry
+	  is available within the transport classes, just defer that
+	  decision to the Transport_Cache_Manager classes. 
+	
+	* tao/Transport_Cache_Manager.cpp:
+	* tao/Transport_Cache_Manager.inl: The make_idle () and
+	  purge_entry () methods now use the classical double-checked
+	  locking optimization pattern before calling the actual 
+	  implementations. 
+
+	  This fixes [BUG 1276]. Thanks to Carlos O'Ryan
+	  <coryan@atdesk.com> for supplying the patches.
+		
 Tue Aug 27 15:56:05 2002  Ossama Othman  <ossama@uci.edu>
 
 	* orbsvcs/tests/Security/Callback/server_i.cpp (test_request):
diff --git a/TAO/tao/Transport.cpp b/TAO/tao/Transport.cpp
index b42243d6a09..79d943f8c0a 100644
--- a/TAO/tao/Transport.cpp
+++ b/TAO/tao/Transport.cpp
@@ -144,10 +144,7 @@ TAO_Transport::~TAO_Transport (void)
   // Avoid making the call if we can.  This may be redundant, unless
   // someone called handle_close() on the connection handler from
   // outside the TAO_Transport.
-  if (this->cache_map_entry_ != 0)
-    {
-      this->transport_cache_manager ().purge_entry (this->cache_map_entry_);
-    }
+  this->transport_cache_manager ().purge_entry (this->cache_map_entry_);
 }
 
 
@@ -369,19 +366,13 @@ TAO_Transport::recache_transport (TAO_Transport_Descriptor_Interface *desc)
 void
 TAO_Transport::purge_entry (void)
 {
-  if (this->cache_map_entry_ != 0)
-    {
-      (void) this->transport_cache_manager ().purge_entry (this->cache_map_entry_);
-    }
+  (void) this->transport_cache_manager ().purge_entry (this->cache_map_entry_);
 }
 
 int
 TAO_Transport::make_idle (void)
 {
-  if (this->cache_map_entry_ != 0)
-    {
-      return this->transport_cache_manager ().make_idle (this->cache_map_entry_);
-    }
+  return this->transport_cache_manager ().make_idle (this->cache_map_entry_);
 
   return -1;
 }
@@ -695,7 +686,7 @@ TAO_Transport::close_connection_shared (int disable_purge,
                                         ACE_Event_Handler * eh)
 {
   // Purge the entry
-  if (!disable_purge && this->cache_map_entry_ != 0)
+  if (!disable_purge)
     {
       this->transport_cache_manager ().purge_entry (this->cache_map_entry_);
     }
diff --git a/TAO/tao/Transport_Cache_Manager.cpp b/TAO/tao/Transport_Cache_Manager.cpp
index 4afe4868fc4..3388cbdbc9d 100644
--- a/TAO/tao/Transport_Cache_Manager.cpp
+++ b/TAO/tao/Transport_Cache_Manager.cpp
@@ -258,6 +258,9 @@ TAO_Transport_Cache_Manager::find_i (const TAO_Cache_ExtId &key,
 int
 TAO_Transport_Cache_Manager::make_idle_i (HASH_MAP_ENTRY *&entry)
 {
+  if(entry == 0)
+    return -1;
+
   // First get the entry again (if at all things had changed in the
   // cache map in the mean time)
 
@@ -329,13 +332,12 @@ TAO_Transport_Cache_Manager::close_i (ACE_Handle_Set &reactor_registered,
 int
 TAO_Transport_Cache_Manager::purge_entry_i (HASH_MAP_ENTRY *&entry)
 {
-  int retval = 0;
+  if (entry == 0)
+    return 0;
 
-  if (entry)
-    {
-      // Remove the entry from the Map
-      retval =  this->cache_map_.unbind (entry);
-    }
+  // Remove the entry from the Map
+ int retval =
+    this->cache_map_.unbind (entry);
 
   // Set the entry pointer to zero
   entry = 0;
@@ -346,12 +348,11 @@ TAO_Transport_Cache_Manager::purge_entry_i (HASH_MAP_ENTRY *&entry)
 void
 TAO_Transport_Cache_Manager::mark_invalid_i (HASH_MAP_ENTRY *&entry)
 {
-  if (entry)
-    {
-      // Mark the entry as not usable
-      entry->int_id_.recycle_state (ACE_RECYCLABLE_PURGABLE_BUT_NOT_IDLE);
-    }
+  if (entry == 0)
+    return;
 
+  // Mark the entry as not usable
+  entry->int_id_.recycle_state (ACE_RECYCLABLE_PURGABLE_BUT_NOT_IDLE);
 }
 
 
diff --git a/TAO/tao/Transport_Cache_Manager.inl b/TAO/tao/Transport_Cache_Manager.inl
index 601864ade4f..c32192b6998 100644
--- a/TAO/tao/Transport_Cache_Manager.inl
+++ b/TAO/tao/Transport_Cache_Manager.inl
@@ -51,10 +51,11 @@ TAO_Transport_Cache_Manager::purge (void)
 ACE_INLINE int
 TAO_Transport_Cache_Manager::purge_entry (HASH_MAP_ENTRY *&entry)
 {
-  ACE_MT (ACE_GUARD_RETURN (ACE_Lock,
-                            guard,
-                            *this->cache_lock_,
-                            -1));
+  // Double checked locking
+  if(entry == 0)
+    return 0;
+
+  ACE_MT (ACE_GUARD_RETURN (ACE_Lock, guard, *this->cache_lock_, -1));
 
   return this->purge_entry_i (entry);
 }
@@ -62,9 +63,11 @@ TAO_Transport_Cache_Manager::purge_entry (HASH_MAP_ENTRY *&entry)
 ACE_INLINE void
 TAO_Transport_Cache_Manager::mark_invalid (HASH_MAP_ENTRY *&entry)
 {
-  ACE_MT (ACE_GUARD (ACE_Lock,
-                     guard,
-                     *this->cache_lock_));
+  if(entry == 0)
+    return;
+
+  // Double checked locking
+  ACE_MT (ACE_GUARD (ACE_Lock, guard, *this->cache_lock_));
 
   this->mark_invalid_i (entry);
 }
@@ -74,10 +77,10 @@ TAO_Transport_Cache_Manager::mark_invalid (HASH_MAP_ENTRY *&entry)
 ACE_INLINE int
 TAO_Transport_Cache_Manager::make_idle (HASH_MAP_ENTRY *&entry)
 {
-  ACE_MT (ACE_GUARD_RETURN (ACE_Lock,
-                            guard,
-                            *this->cache_lock_,
-                            -1));
+  if(entry == 0)
+    return -1;
+
+  ACE_MT (ACE_GUARD_RETURN (ACE_Lock, guard, *this->cache_lock_, -1));
   return this->make_idle_i (entry);
 }