blob: 5d355d5d52405150938b8d1d294d1148d55a5be6 [file] [log] [blame]
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <map>
#include <string>
#include "base/base_export.h"
#include "base/basictypes.h"
#include "base/compiler_specific.h"
#include "base/memory/scoped_ptr.h"
#include "base/metrics/histogram_base.h"
#include "base/synchronization/lock.h"
namespace base {
class HistogramSamples;
class BASE_EXPORT_PRIVATE SparseHistogram : public HistogramBase {
// If there's one with same name, return the existing one. If not, create a
// new one.
static HistogramBase* FactoryGet(const std::string& name, int32 flags);
virtual ~SparseHistogram();
// HistogramBase implementation:
virtual HistogramType GetHistogramType() const override;
virtual bool HasConstructionArguments(Sample minimum,
Sample maximum,
size_t bucket_count) const override;
virtual void Add(Sample value) override;
virtual void WriteHTMLGraph(std::string* output) const override;
virtual void WriteAscii(std::string* output) const override;
virtual scoped_ptr<HistogramSamples> SnapshotSamples() const override;
// Clients should always use FactoryGet to create SparseHistogram.
SparseHistogram(const std::string& name);
virtual void GetParameters(DictionaryValue* params) const override;
virtual void GetCountAndBucketData(Count* count,
ListValue* buckets) const override;
friend class SparseHistogramTest; // For constuctor calling.
// Protects access to |sample_counts_| and |redundant_count_|.
mutable base::Lock lock_;
std::map<HistogramBase::Sample, HistogramBase::Count> sample_counts_;
HistogramBase::Count redundant_count_;
} // namespace base