chromium/base/metrics/persistent_histogram_allocator.h

// Copyright 2016 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef BASE_METRICS_PERSISTENT_HISTOGRAM_ALLOCATOR_H_
#define BASE_METRICS_PERSISTENT_HISTOGRAM_ALLOCATOR_H_

#include <atomic>
#include <map>
#include <memory>
#include <optional>
#include <string>
#include <string_view>
#include <vector>

#include "base/base_export.h"
#include "base/memory/raw_ptr.h"
#include "base/metrics/histogram_base.h"
#include "base/metrics/persistent_memory_allocator.h"
#include "base/metrics/ranges_manager.h"
#include "base/process/process_handle.h"
#include "base/synchronization/lock.h"
#include "build/build_config.h"

namespace base {

class BucketRanges;
class FilePath;
class PersistentSampleMapRecords;
class PersistentSparseHistogramDataManager;
class UnsafeSharedMemoryRegion;

// A data manager for sparse histograms so each instance of such doesn't have
// to separately iterate over the entire memory segment.
class BASE_EXPORT PersistentSparseHistogramDataManager { … };


// This class manages sample-records used by a PersistentSampleMap container
// that underlies a persistent SparseHistogram object. It is broken out into a
// top-level class so that it can be forward-declared in other header files
// rather than include this entire file as would be necessary if it were
// declared within the PersistentSparseHistogramDataManager class above.
class BASE_EXPORT PersistentSampleMapRecords { … };


// This class manages histograms created within a PersistentMemoryAllocator.
class BASE_EXPORT PersistentHistogramAllocator { … };


// A special case of the PersistentHistogramAllocator that operates on a
// global scale, collecting histograms created through standard macros and
// the FactoryGet() method.
class BASE_EXPORT GlobalHistogramAllocator
    : public PersistentHistogramAllocator { … };

}  // namespace base

#endif  // BASE_METRICS_PERSISTENT_HISTOGRAM_ALLOCATOR_H_