3c12f4dadb
Reason for revert: Caused static initializers. BUG=chromium:556866 TBR=tommi@webrtc.org Original issue's description: > Create rtc::AtomicInt POD struct. > > Prevents accidental non-atomic reads, increments and stores since > "volatile int" doesn't enforce atomic usage. > > BUG= > R=kwiberg@webrtc.org, tommi@webrtc.org > > Committed: https://crrev.com/b27f590ece487819c3d1fda400315e582fb975b6 > Cr-Commit-Position: refs/heads/master@{#10657} TBR=kwiberg@webrtc.org,tommi@webrtc.org NOPRESUBMIT=true NOTREECHECKS=true NOTRY=true BUG= Review URL: https://codereview.webrtc.org/1453093002 Cr-Commit-Position: refs/heads/master@{#10669}
69 lines
2.2 KiB
C++
69 lines
2.2 KiB
C++
/*
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* Copyright 2011 The WebRTC Project Authors. All rights reserved.
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*
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* Use of this source code is governed by a BSD-style license
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* that can be found in the LICENSE file in the root of the source
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* tree. An additional intellectual property rights grant can be found
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* in the file PATENTS. All contributing project authors may
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* be found in the AUTHORS file in the root of the source tree.
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*/
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#ifndef WEBRTC_BASE_ATOMICOPS_H_
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#define WEBRTC_BASE_ATOMICOPS_H_
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#if defined(WEBRTC_WIN)
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// Include winsock2.h before including <windows.h> to maintain consistency with
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// win32.h. We can't include win32.h directly here since it pulls in
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// headers such as basictypes.h which causes problems in Chromium where webrtc
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// exists as two separate projects, webrtc and libjingle.
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#include <winsock2.h>
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#include <windows.h>
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#endif // defined(WEBRTC_WIN)
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namespace rtc {
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class AtomicOps {
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public:
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#if defined(WEBRTC_WIN)
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// Assumes sizeof(int) == sizeof(LONG), which it is on Win32 and Win64.
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static int Increment(volatile int* i) {
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return ::InterlockedIncrement(reinterpret_cast<volatile LONG*>(i));
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}
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static int Decrement(volatile int* i) {
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return ::InterlockedDecrement(reinterpret_cast<volatile LONG*>(i));
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}
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static int AcquireLoad(volatile const int* i) {
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return *i;
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}
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static void ReleaseStore(volatile int* i, int value) {
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*i = value;
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}
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static int CompareAndSwap(volatile int* i, int old_value, int new_value) {
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return ::InterlockedCompareExchange(reinterpret_cast<volatile LONG*>(i),
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new_value,
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old_value);
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}
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#else
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static int Increment(volatile int* i) {
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return __sync_add_and_fetch(i, 1);
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}
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static int Decrement(volatile int* i) {
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return __sync_sub_and_fetch(i, 1);
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}
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static int AcquireLoad(volatile const int* i) {
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return __atomic_load_n(i, __ATOMIC_ACQUIRE);
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}
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static void ReleaseStore(volatile int* i, int value) {
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__atomic_store_n(i, value, __ATOMIC_RELEASE);
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}
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static int CompareAndSwap(volatile int* i, int old_value, int new_value) {
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return __sync_val_compare_and_swap(i, old_value, new_value);
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}
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#endif
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};
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}
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#endif // WEBRTC_BASE_ATOMICOPS_H_
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