1 files changed, 17 insertions, 76 deletions

diff --git a/ipc/chromium/src/base/condition_variable.h b/ipc/chromium/src/base/condition_variable.h
index 63610e0e3b..f274c8eabe 100644
--- a/ipc/chromium/src/base/condition_variable.h
+++ b/ipc/chromium/src/base/condition_variable.h
@@ -1,5 +1,4 @@
-/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -66,7 +65,17 @@
 #ifndef BASE_CONDITION_VARIABLE_H_
 #define BASE_CONDITION_VARIABLE_H_
 
+#include "base/basictypes.h"
 #include "base/lock.h"
+#include "build/build_config.h"
+
+#if defined(OS_POSIX)
+#include <pthread.h>
+#endif
+
+#if defined(OS_WIN)
+#include <windows.h>
+#endif
 
 namespace base {
   class TimeDelta;
@@ -80,11 +89,13 @@ class ConditionVariable {
   ~ConditionVariable();
 
   // Wait() releases the caller's critical section atomically as it starts to
-  // sleep, and the reacquires it when it is signaled.
+  // sleep, and the reacquires it when it is signaled. The wait functions are
+  // susceptible to spurious wakeups. (See usage note 1 for more details.)
   void Wait();
   void TimedWait(const base::TimeDelta& max_time);
 
-  // Broadcast() revives all waiting threads.
+  // Broadcast() revives all waiting threads. (See usage note 2 for more
+  // details.)
   void Broadcast();
   // Signal() revives one waiting thread.
   void Signal();
@@ -92,81 +103,11 @@ class ConditionVariable {
  private:
 
 #if defined(OS_WIN)
-
-  // Define Event class that is used to form circularly linked lists.
-  // The list container is an element with NULL as its handle_ value.
-  // The actual list elements have a non-zero handle_ value.
-  // All calls to methods MUST be done under protection of a lock so that links
-  // can be validated.  Without the lock, some links might asynchronously
-  // change, and the assertions would fail (as would list change operations).
-  class Event {
-   public:
-    // Default constructor with no arguments creates a list container.
-    Event();
-    ~Event();
-
-    // InitListElement transitions an instance from a container, to an element.
-    void InitListElement();
-
-    // Methods for use on lists.
-    bool IsEmpty() const;
-    void PushBack(Event* other);
-    Event* PopFront();
-    Event* PopBack();
-
-    // Methods for use on list elements.
-    // Accessor method.
-    HANDLE handle() const;
-    // Pull an element from a list (if it's in one).
-    Event* Extract();
-
-    // Method for use on a list element or on a list.
-    bool IsSingleton() const;
-
-   private:
-    // Provide pre/post conditions to validate correct manipulations.
-    bool ValidateAsDistinct(Event* other) const;
-    bool ValidateAsItem() const;
-    bool ValidateAsList() const;
-    bool ValidateLinks() const;
-
-    HANDLE handle_;
-    Event* next_;
-    Event* prev_;
-    DISALLOW_COPY_AND_ASSIGN(Event);
-  };
-
-  // Note that RUNNING is an unlikely number to have in RAM by accident.
-  // This helps with defensive destructor coding in the face of user error.
-  enum RunState { SHUTDOWN = 0, RUNNING = 64213 };
-
-  // Internal implementation methods supporting Wait().
-  Event* GetEventForWaiting();
-  void RecycleEvent(Event* used_event);
-
-  RunState run_state_;
-
-  // Private critical section for access to member data.
-  Lock internal_lock_;
-
-  // Lock that is acquired before calling Wait().
-  Lock& user_lock_;
-
-  // Events that threads are blocked on.
-  Event waiting_list_;
-
-  // Free list for old events.
-  Event recycling_list_;
-  int recycling_list_size_;
-
-  // The number of allocated, but not yet deleted events.
-  int allocation_counter_;
-
+  CONDITION_VARIABLE cv_;
+  SRWLOCK* const srwlock_;
 #elif defined(OS_POSIX)
-
   pthread_cond_t condition_;
   pthread_mutex_t* user_mutex_;
-
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(ConditionVariable);