shaka-packager/base/metrics/sparse_histogram.h

118 lines
3.8 KiB
C++

// 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.
#ifndef BASE_METRICS_SPARSE_HISTOGRAM_H_
#define BASE_METRICS_SPARSE_HISTOGRAM_H_
#include <map>
#include <string>
#include "base/base_export.h"
#include "base/basictypes.h"
#include "base/compiler_specific.h"
#include "base/logging.h"
#include "base/memory/scoped_ptr.h"
#include "base/metrics/histogram_base.h"
#include "base/metrics/sample_map.h"
#include "base/synchronization/lock.h"
namespace base {
// The common code for different SparseHistogram macros.
#define HISTOGRAM_SPARSE_COMMON(name, sample, flag) \
do { \
base::HistogramBase* histogram( \
base::SparseHistogram::FactoryGet(name, flag)); \
DCHECK_EQ(histogram->histogram_name(), name); \
histogram->Add(sample); \
} while (0)
#define HISTOGRAM_SPARSE_SLOWLY(name, sample) \
HISTOGRAM_SPARSE_COMMON(name, sample, base::HistogramBase::kNoFlags)
#define UMA_HISTOGRAM_SPARSE_SLOWLY(name, sample) \
HISTOGRAM_SPARSE_COMMON(name, sample, \
base::HistogramBase::kUmaTargetedHistogramFlag)
//------------------------------------------------------------------------------
// Define debug only version of macros.
#ifndef NDEBUG
#define DHISTOGRAM_SPARSE_SLOWLY(name, sample) \
HISTOGRAM_SPARSE_SLOWLY(name, sample)
#else // NDEBUG
#define DHISTOGRAM_SPARSE_SLOWLY(name, sample) \
while (0) { \
static_cast<void>(name); \
static_cast<void>(sample); \
}
#endif // NDEBUG
class HistogramSamples;
class BASE_EXPORT_PRIVATE SparseHistogram : public HistogramBase {
public:
// 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 expected_minimum,
Sample expected_maximum,
size_t expected_bucket_count) const OVERRIDE;
virtual void Add(Sample value) OVERRIDE;
virtual void AddSamples(const HistogramSamples& samples) OVERRIDE;
virtual bool AddSamplesFromPickle(PickleIterator* iter) OVERRIDE;
virtual scoped_ptr<HistogramSamples> SnapshotSamples() const OVERRIDE;
virtual void WriteHTMLGraph(std::string* output) const OVERRIDE;
virtual void WriteAscii(std::string* output) const OVERRIDE;
protected:
// HistogramBase implementation:
virtual bool SerializeInfoImpl(Pickle* pickle) const OVERRIDE;
private:
// Clients should always use FactoryGet to create SparseHistogram.
explicit SparseHistogram(const std::string& name);
friend BASE_EXPORT_PRIVATE HistogramBase* DeserializeHistogramInfo(
PickleIterator* iter);
static HistogramBase* DeserializeInfoImpl(PickleIterator* iter);
virtual void GetParameters(DictionaryValue* params) const OVERRIDE;
virtual void GetCountAndBucketData(Count* count,
int64* sum,
ListValue* buckets) const OVERRIDE;
// Helpers for emitting Ascii graphic. Each method appends data to output.
void WriteAsciiImpl(bool graph_it,
const std::string& newline,
std::string* output) const;
// Write a common header message describing this histogram.
void WriteAsciiHeader(const Count total_count,
std::string* output) const;
// For constuctor calling.
friend class SparseHistogramTest;
// Protects access to |samples_|.
mutable base::Lock lock_;
SampleMap samples_;
DISALLOW_COPY_AND_ASSIGN(SparseHistogram);
};
} // namespace base
#endif // BASE_METRICS_SPARSE_HISTOGRAM_H_