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-rw-r--r--security/sandbox/chromium/base/lazy_instance.cc54
1 files changed, 0 insertions, 54 deletions
diff --git a/security/sandbox/chromium/base/lazy_instance.cc b/security/sandbox/chromium/base/lazy_instance.cc
deleted file mode 100644
index 54680655a..000000000
--- a/security/sandbox/chromium/base/lazy_instance.cc
+++ /dev/null
@@ -1,54 +0,0 @@
-// 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.
-
-#include "base/lazy_instance.h"
-
-#include "base/at_exit.h"
-#include "base/atomicops.h"
-#include "base/threading/platform_thread.h"
-
-namespace base {
-namespace internal {
-
-// TODO(joth): This function could be shared with Singleton, in place of its
-// WaitForInstance() call.
-bool NeedsLazyInstance(subtle::AtomicWord* state) {
- // Try to create the instance, if we're the first, will go from 0 to
- // kLazyInstanceStateCreating, otherwise we've already been beaten here.
- // The memory access has no memory ordering as state 0 and
- // kLazyInstanceStateCreating have no associated data (memory barriers are
- // all about ordering of memory accesses to *associated* data).
- if (subtle::NoBarrier_CompareAndSwap(state, 0,
- kLazyInstanceStateCreating) == 0)
- // Caller must create instance
- return true;
-
- // It's either in the process of being created, or already created. Spin.
- // The load has acquire memory ordering as a thread which sees
- // state_ == STATE_CREATED needs to acquire visibility over
- // the associated data (buf_). Pairing Release_Store is in
- // CompleteLazyInstance().
- while (subtle::Acquire_Load(state) == kLazyInstanceStateCreating) {
- PlatformThread::YieldCurrentThread();
- }
- // Someone else created the instance.
- return false;
-}
-
-void CompleteLazyInstance(subtle::AtomicWord* state,
- subtle::AtomicWord new_instance,
- void* lazy_instance,
- void (*dtor)(void*)) {
- // Instance is created, go from CREATING to CREATED.
- // Releases visibility over private_buf_ to readers. Pairing Acquire_Load's
- // are in NeedsInstance() and Pointer().
- subtle::Release_Store(state, new_instance);
-
- // Make sure that the lazily instantiated object will get destroyed at exit.
- if (dtor)
- AtExitManager::RegisterCallback(dtor, lazy_instance);
-}
-
-} // namespace internal
-} // namespace base