/*
 * Copyright (C) 2013 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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#ifndef THIRD_PARTY_BLINK_RENDERER_PLATFORM_WTF_ALLOCATOR_PARTITIONS_H_
#define THIRD_PARTY_BLINK_RENDERER_PLATFORM_WTF_ALLOCATOR_PARTITIONS_H_

#include "base/check.h"
#include "base/memory/scoped_refptr.h"
#include "base/numerics/checked_math.h"
#include "partition_alloc/partition_alloc_forward.h"
#include "third_party/blink/renderer/platform/wtf/wtf_export.h"

namespace base {
class SequencedTaskRunner;
}

namespace blink {

class WTF_EXPORT Partitions {
 public:
  // Name of allocator used by tracing for marking sub-allocations while take
  // memory snapshots.
  static const char* const kAllocatedObjectPoolName;

  // Should be called on the thread which is or will become the main one.
  static void Initialize();
  static void InitializeArrayBufferPartition();
  static void StartMemoryReclaimer(
      scoped_refptr<base::SequencedTaskRunner> task_runner);

  // The ArrayBufferPartition is initialized separately from the other
  // partitions and so may not always be available. This function can be used to
  // determine whether the partition has been initialized.
  ALWAYS_INLINE static bool ArrayBufferPartitionInitialized() {
    return array_buffer_root_ != nullptr;
  }

  ALWAYS_INLINE static partition_alloc::PartitionRoot* ArrayBufferPartition() {
    DCHECK(initialized_);
    DCHECK(ArrayBufferPartitionInitialized());
    return array_buffer_root_;
  }

  ALWAYS_INLINE static partition_alloc::PartitionRoot* BufferPartition() {
    DCHECK(initialized_);
    return buffer_root_;
  }

  ALWAYS_INLINE static size_t ComputeAllocationSize(size_t count, size_t size) {
    base::CheckedNumeric<size_t> total = count;
    total *= size;
    return total.ValueOrDie();
  }

  static size_t TotalSizeOfCommittedPages();

  static size_t TotalActiveBytes();

  static void DumpMemoryStats(bool is_light_dump,
                              partition_alloc::PartitionStatsDumper*);

  static void* PA_MALLOC_FN BufferMalloc(size_t n, const char* type_name);
  static void* BufferTryRealloc(void* p, size_t n, const char* type_name);
  static void* PA_MALLOC_FN BufferTryAlignedZeroedMalloc(size_t n,
                                                         size_t alignment,
                                                         const char* type_name);
  static void BufferFree(void* p);
  static void BufferAlignedFree(void* p);
  static void BufferFreeWithSize(void* p, size_t size);
  static size_t BufferPotentialCapacity(size_t n);

  static void* PA_MALLOC_FN FastMalloc(size_t n, const char* type_name);
  static void* PA_MALLOC_FN FastZeroedMalloc(size_t n, const char* type_name);
  static void FastFree(void* p);

  static void HandleOutOfMemory(size_t size);

  // Adjusts the size of the partitions based on process state.
  static void AdjustPartitionsForForeground();
  static void AdjustPartitionsForBackground();

 private:
  ALWAYS_INLINE static partition_alloc::PartitionRoot* FastMallocPartition() {
    DCHECK(initialized_);
    return fast_malloc_root_;
  }

  static bool InitializeOnce();

  static bool initialized_;
  // See Allocator.md for a description of these partitions.
  static partition_alloc::PartitionRoot* fast_malloc_root_;
  static partition_alloc::PartitionRoot* array_buffer_root_;
  static partition_alloc::PartitionRoot* buffer_root_;
};

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_PLATFORM_WTF_ALLOCATOR_PARTITIONS_H_