1// Copyright 2013 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#include "base/memory/discardable_memory_emulated.h" 6 7#include "base/lazy_instance.h" 8#include "base/memory/discardable_memory_provider.h" 9 10namespace base { 11 12namespace { 13 14base::LazyInstance<internal::DiscardableMemoryProvider>::Leaky g_provider = 15 LAZY_INSTANCE_INITIALIZER; 16 17} // namespace 18 19namespace internal { 20 21DiscardableMemoryEmulated::DiscardableMemoryEmulated(size_t size) 22 : is_locked_(false) { 23 g_provider.Pointer()->Register(this, size); 24} 25 26DiscardableMemoryEmulated::~DiscardableMemoryEmulated() { 27 if (is_locked_) 28 Unlock(); 29 g_provider.Pointer()->Unregister(this); 30} 31 32bool DiscardableMemoryEmulated::Initialize() { 33 return Lock() == DISCARDABLE_MEMORY_PURGED; 34} 35 36LockDiscardableMemoryStatus DiscardableMemoryEmulated::Lock() { 37 DCHECK(!is_locked_); 38 39 bool purged = false; 40 memory_ = g_provider.Pointer()->Acquire(this, &purged); 41 if (!memory_) 42 return DISCARDABLE_MEMORY_FAILED; 43 44 is_locked_ = true; 45 return purged ? DISCARDABLE_MEMORY_PURGED : DISCARDABLE_MEMORY_SUCCESS; 46} 47 48void DiscardableMemoryEmulated::Unlock() { 49 DCHECK(is_locked_); 50 g_provider.Pointer()->Release(this, memory_.Pass()); 51 is_locked_ = false; 52} 53 54void* DiscardableMemoryEmulated::Memory() const { 55 DCHECK(memory_); 56 return memory_.get(); 57} 58 59// static 60void DiscardableMemoryEmulated::PurgeForTesting() { 61 g_provider.Pointer()->PurgeAll(); 62} 63 64} // namespace internal 65} // namespace base 66