components/metrics/histogram_encoder.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 // This file defines an utility function that records any changes in a given
   6 // histogram for transmission.
   7
   8 #ifndef COMPONENTS_METRICS_HISTOGRAM_ENCODER_H_
   9 #define COMPONENTS_METRICS_HISTOGRAM_ENCODER_H_
  10
  11 #include <string>
  12
  13 #include "base/basictypes.h"
  14 #include "components/metrics/proto/chrome_user_metrics_extension.pb.h"
  15
  16 namespace base {
  17 class HistogramSamples;
  18 }
  19
  20 namespace metrics {
  21
  22 // Record any changes (histogram deltas of counts from |snapshot|) into
  23 // |uma_proto| for the given histogram (|histogram_name|).
  24 void EncodeHistogramDelta(const std::string& histogram_name,
  25                           const base::HistogramSamples& snapshot,
  26                           ChromeUserMetricsExtension* uma_proto);
  27
  28 }  // namespace metrics
  29
  30 #endif  // COMPONENTS_METRICS_HISTOGRAM_ENCODER_H_