Chromium Code Reviews| Index: base/metrics/histogram_samples.h |
| =================================================================== |
| --- base/metrics/histogram_samples.h (revision 0) |
| +++ base/metrics/histogram_samples.h (revision 0) |
| @@ -0,0 +1,82 @@ |
| +// 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_HISTOGRAM_SAMPLES_H_ |
| +#define BASE_METRICS_HISTOGRAM_SAMPLES_H_ |
| + |
| +#include "base/basictypes.h" |
| +#include "base/metrics/histogram_base.h" |
| +#include "base/memory/scoped_ptr.h" |
| + |
| +class Pickle; |
| +class PickleIterator; |
| + |
| +namespace base { |
| + |
| +class SampleCountIterator; |
| + |
| +// HistogramSamples is a container storing all samples of a histogram. |
| +class BASE_EXPORT HistogramSamples { |
| + public: |
| + HistogramSamples(); |
| + virtual ~HistogramSamples(); |
| + |
| + virtual void Accumulate(HistogramBase::Sample value, |
| + HistogramBase::Count count) = 0; |
| + virtual HistogramBase::Count GetCount(HistogramBase::Sample value) const = 0; |
| + virtual HistogramBase::Count TotalCount() const = 0; |
| + |
| + virtual void Add(const HistogramSamples& other); |
| + |
| + // Add from serialized samples. |
| + virtual bool AddFromPickle(PickleIterator* iter); |
| + |
| + virtual void Subtract(const HistogramSamples& other); |
| + |
| + virtual scoped_ptr<SampleCountIterator> Iterator() const = 0; |
| + virtual bool Serialize(Pickle* pickle) const; |
| + |
| + // Accessor fuctions. |
| + int64 sum() const { return sum_; } |
| + HistogramBase::Count redundant_count() const { return redundant_count_; } |
| + |
| + protected: |
| + // Add/subtract sample counts data from the iterator. |
| + virtual bool AddSubtractImpl(SampleCountIterator* iter, bool is_add) = 0; |
| + |
| + void set_sum(int64 sum) { sum_ = sum; } |
| + void set_redundant_count(HistogramBase::Count redundant_count) { |
| + redundant_count_ = redundant_count; |
| + } |
| + |
| + private: |
| + int64 sum_; |
| + |
| + // |redundant_count_| helps identify memory corruption. It redundantly stores |
| + // the total number of samples accumulated in the histogram. We can compare |
| + // this count to the sum of the counts (TotalCount() function), and detect |
| + // problems. Note, depending on the implementation of different histogram |
| + // types, there might be races during histogram accumulation and snapshotting |
| + // that we choose to accept. In this case, the tallies might mismatch even |
| + // when no memory corruption has happened. |
| + HistogramBase::Count redundant_count_; |
| +}; |
| + |
| +class BASE_EXPORT SampleCountIterator { |
| + public: |
| + virtual ~SampleCountIterator(); |
| + |
| + virtual bool Done() = 0; |
|
Ilya Sherman
2012/08/29 08:48:16
nit: const?
kaiwang
2012/08/29 22:42:16
Done.
|
| + virtual void Next() = 0; |
| + |
| + // Get the sample and count at current position. |
| + // |min| |max| and |count| can be NULL if the value is not interested. |
|
Ilya Sherman
2012/08/29 08:48:16
nit: "interested" -> "of interest"
kaiwang
2012/08/29 22:42:16
Done.
|
| + virtual void Get(HistogramBase::Sample* min, |
| + HistogramBase::Sample* max, |
| + HistogramBase::Count* count) = 0; |
|
Ilya Sherman
2012/08/29 08:48:16
nit: const?
kaiwang
2012/08/29 22:42:16
Done.
|
| +}; |
| + |
| +} // namespace base |
| + |
| +#endif // BASE_METRICS_HISTOGRAM_SAMPLES_H_ |
| Property changes on: base/metrics/histogram_samples.h |
| ___________________________________________________________________ |
| Added: svn:eol-style |
| + LF |