[asp.net] Fix for bug #669807. Cache session item locks as the item m…

…ight be cleared before the lock needs to be released.
baulig · Feb 21, 2011 · 01e4a9b · 01e4a9b
1 parent e09f898
commit 01e4a9b
Showing 1 changed file with 22 additions and 11 deletions.
diff --git a/mcs/class/System.Web/System.Web.SessionState_2.0/SessionInProcHandler.cs b/mcs/class/System.Web/System.Web.SessionState_2.0/SessionInProcHandler.cs
@@ -254,17 +254,20 @@ public override void InitializeRequest (HttpContext context)
 				return;
 
 			bool locked = false;
+			ReaderWriterLockSlim itemLock = null;
+
 			try {
-				if (item.rwlock.TryEnterWriteLock (lockAcquireTimeout))
+				itemLock = item.rwlock;
+				if (itemLock != null && itemLock.TryEnterWriteLock (lockAcquireTimeout))
 					locked = true;
 				else
 					throw new ApplicationException ("Failed to acquire lock");
 				item.locked = false;
 			} catch {
 				throw;
 			} finally {
-				if (locked)
-					item.rwlock.ExitWriteLock ();
+				if (locked && itemLock != null)
+					itemLock.ExitWriteLock ();
 			}
 		}
 
@@ -282,8 +285,11 @@ public override void InitializeRequest (HttpContext context)
 				return;
 
 			bool locked = false;
+			ReaderWriterLockSlim itemLock = null;
+
 			try {
-				if (inProcItem.rwlock.TryEnterWriteLock (lockAcquireTimeout))
+				itemLock = inProcItem.rwlock;
+				if (itemLock != null && itemLock.TryEnterWriteLock (lockAcquireTimeout))
 					locked = true;
 				else
 					throw new ApplicationException ("Failed to acquire lock after");
@@ -292,7 +298,7 @@ public override void InitializeRequest (HttpContext context)
 				throw;
 			} finally {
 				if (locked)
-					inProcItem.rwlock.ExitWriteLock ();
+					itemLock.ExitWriteLock ();
 			}
 		}
 
@@ -307,8 +313,11 @@ public override void ResetItemTimeout (HttpContext context, string id)
 				return;
 
 			bool locked = false;
+			ReaderWriterLockSlim itemLock = null;
+
 			try {
-				if (item.rwlock.TryEnterWriteLock (lockAcquireTimeout))
+				itemLock = item.rwlock;
+				if (itemLock != null && itemLock.TryEnterWriteLock (lockAcquireTimeout))
 					locked = true;
 				else
 					throw new ApplicationException ("Failed to acquire lock after");
@@ -318,8 +327,8 @@ public override void ResetItemTimeout (HttpContext context, string id)
 			} catch {
 				throw;
 			} finally {
-				if (locked)
-					item.rwlock.ExitWriteLock ();
+				if (locked && itemLock != null)
+					itemLock.ExitWriteLock ();
 			}
 		}
 
@@ -366,8 +375,10 @@ public override void ResetItemTimeout (HttpContext context, string id)
 			}
 
 			bool locked = false;
+			ReaderWriterLockSlim itemLock = null;
 			try {
-				if (inProcItem.rwlock.TryEnterWriteLock (lockAcquireTimeout))
+				itemLock = inProcItem.rwlock;
+				if (itemLock != null && itemLock.TryEnterWriteLock (lockAcquireTimeout))
 					locked = true;
 				else
 					throw new ApplicationException ("Failed to acquire lock");
@@ -378,8 +389,8 @@ public override void ResetItemTimeout (HttpContext context, string id)
 			} catch {
 				throw;
 			} finally {
-				if (locked)
-					inProcItem.rwlock.ExitWriteLock ();
+				if (locked && itemLock != null)
+					itemLock.ExitWriteLock ();
 			}
 		}