Add a default implementation in metrics_default.cc of histograms methods in system_wrappers/interfac

webrtc/test/histogram.cc

-/*
- *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree. An additional intellectual property rights grant can be found
- *  in the file PATENTS.  All contributing project authors may
- *  be found in the AUTHORS file in the root of the source tree.
- */
-
-#include "webrtc/test/histogram.h"
-
-#include <map>
-
-#include "webrtc/base/checks.h"
-#include "webrtc/base/criticalsection.h"
-#include "webrtc/base/thread_annotations.h"
-#include "webrtc/system_wrappers/include/metrics.h"
-
-// Test implementation of histogram methods in
-// webrtc/system_wrappers/include/metrics.h.
-
-namespace webrtc {
-namespace {
-struct SampleInfo {
-  SampleInfo(const std::string& name) : name_(name), last_(-1), total_(0) {}
-  const std::string name_;
-  int last_;   // Last added sample.
-  int total_;  // Total number of added samples.
-};
-
-rtc::CriticalSection histogram_crit_;
-// Map holding info about added samples to a histogram (mapped by the histogram
-// name).
-std::map<std::string, SampleInfo> histograms_ GUARDED_BY(histogram_crit_);
-}  // namespace
-
-namespace metrics {
-Histogram* HistogramFactoryGetCounts(const std::string& name, int min, int max,
-                                     int bucket_count) {
-  rtc::CritScope cs(&histogram_crit_);
-  if (histograms_.find(name) == histograms_.end()) {
-    histograms_.insert(std::make_pair(name, SampleInfo(name)));
-  }
-  auto it = histograms_.find(name);
-  return reinterpret_cast<Histogram*>(&it->second);
-}
-
-Histogram* HistogramFactoryGetEnumeration(const std::string& name,
-                                          int boundary) {
-  rtc::CritScope cs(&histogram_crit_);
-  if (histograms_.find(name) == histograms_.end()) {
-    histograms_.insert(std::make_pair(name, SampleInfo(name)));
-  }
-  auto it = histograms_.find(name);
-  return reinterpret_cast<Histogram*>(&it->second);
-}
-
-void HistogramAdd(
-    Histogram* histogram_pointer, const std::string& name, int sample) {
-  rtc::CritScope cs(&histogram_crit_);
-  SampleInfo* ptr = reinterpret_cast<SampleInfo*>(histogram_pointer);
-  // The name should not vary.
-  RTC_CHECK(ptr->name_ == name);
-  ptr->last_ = sample;
-  ++ptr->total_;
-}
-}  // namespace metrics
-
-namespace test {
-int LastHistogramSample(const std::string& name) {
-  rtc::CritScope cs(&histogram_crit_);
-  const auto it = histograms_.find(name);
-  if (it == histograms_.end()) {
-    return -1;
-  }
-  return it->second.last_;
-}
-
-int NumHistogramSamples(const std::string& name) {
-  rtc::CritScope cs(&histogram_crit_);
-  const auto it = histograms_.find(name);
-  if (it == histograms_.end()) {
-    return 0;
-  }
-  return it->second.total_;
-}
-
-void ClearHistograms() {
-  rtc::CritScope cs(&histogram_crit_);
-  for (auto& it : histograms_) {
-    it.second.last_ = -1;
-    it.second.total_ = 0;
-  }
-}
-}  // namespace test
-}  // namespace webrtc