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@@ -1,77 +0,0 @@
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-//
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-// Urho3D Engine
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-// Copyright (c) 2008-2011 Lasse Öörni
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-//
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-// Permission is hereby granted, free of charge, to any person obtaining a copy
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-// of this software and associated documentation files (the "Software"), to deal
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-// in the Software without restriction, including without limitation the rights
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-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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-// copies of the Software, and to permit persons to whom the Software is
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-// furnished to do so, subject to the following conditions:
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-//
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-// The above copyright notice and this permission notice shall be included in
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-// all copies or substantial portions of the Software.
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-//
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-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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-// THE SOFTWARE.
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-//
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-
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-#pragma once
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-
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-/// Non-reentrant userspace mutual exclusion primitive.
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-class SpinLock
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-{
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-public:
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- /// Construct.
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- SpinLock() :
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- locked_(0)
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- {
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- }
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-
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- /// Acquire the lock. Spin in a loop while waiting.
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- void Acquire()
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- {
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- for (;;)
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- {
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- if (TestAndSet(&locked_, 1) == 0)
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- break;
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- }
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- }
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-
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- /// Try to acquire the lock without waiting. Return true if successfully acquired.
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- bool TryAcquire()
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- {
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- return TestAndSet(&locked_, 1) == 0;
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- }
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-
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- /// Release the lock.
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- void Release()
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- {
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- locked_ = 0;
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- }
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-
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-private:
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- /// Test-and-set a value atomically and return the previous value.
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- static unsigned TestAndSet(unsigned* dest, unsigned newValue)
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- {
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- #ifdef _MSC_VER
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- __asm
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- {
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- mov edx, dest
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- mov eax, newValue
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- lock xchg eax, dword ptr [edx]
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- }
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- #else
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- return __sync_lock_test_and_set(dest, newValue);
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- #endif
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- }
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-
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- /// Locked flag.
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- unsigned locked_;
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-};
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-
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