Repo created

TMessagesProj/jni/voip/webrtc/base/metrics/sample_map.cc

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+// 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 "base/metrics/sample_map.h"
+
+#include "base/logging.h"
+#include "base/numerics/safe_conversions.h"
+#include "base/stl_util.h"
+
+namespace base {
+
+typedef HistogramBase::Count Count;
+typedef HistogramBase::Sample Sample;
+
+namespace {
+
+// An iterator for going through a SampleMap. The logic here is identical
+// to that of PersistentSampleMapIterator but with different data structures.
+// Changes here likely need to be duplicated there.
+class SampleMapIterator : public SampleCountIterator {
+ public:
+  typedef std::map<HistogramBase::Sample, HistogramBase::Count>
+      SampleToCountMap;
+
+  explicit SampleMapIterator(const SampleToCountMap& sample_counts);
+  ~SampleMapIterator() override;
+
+  // SampleCountIterator:
+  bool Done() const override;
+  void Next() override;
+  void Get(HistogramBase::Sample* min,
+           int64_t* max,
+           HistogramBase::Count* count) const override;
+
+ private:
+  void SkipEmptyBuckets();
+
+  SampleToCountMap::const_iterator iter_;
+  const SampleToCountMap::const_iterator end_;
+};
+
+SampleMapIterator::SampleMapIterator(const SampleToCountMap& sample_counts)
+    : iter_(sample_counts.begin()),
+      end_(sample_counts.end()) {
+  SkipEmptyBuckets();
+}
+
+SampleMapIterator::~SampleMapIterator() = default;
+
+bool SampleMapIterator::Done() const {
+  return iter_ == end_;
+}
+
+void SampleMapIterator::Next() {
+  DCHECK(!Done());
+  ++iter_;
+  SkipEmptyBuckets();
+}
+
+void SampleMapIterator::Get(Sample* min, int64_t* max, Count* count) const {
+  DCHECK(!Done());
+  if (min)
+    *min = iter_->first;
+  if (max)
+    *max = strict_cast<int64_t>(iter_->first) + 1;
+  if (count)
+    *count = iter_->second;
+}
+
+void SampleMapIterator::SkipEmptyBuckets() {
+  while (!Done() && iter_->second == 0) {
+    ++iter_;
+  }
+}
+
+}  // namespace
+
+SampleMap::SampleMap() : SampleMap(0) {}
+
+SampleMap::SampleMap(uint64_t id) : HistogramSamples(id, new LocalMetadata()) {}
+
+SampleMap::~SampleMap() {
+  delete static_cast<LocalMetadata*>(meta());
+}
+
+void SampleMap::Accumulate(Sample value, Count count) {
+  sample_counts_[value] += count;
+  IncreaseSumAndCount(strict_cast<int64_t>(count) * value, count);
+}
+
+Count SampleMap::GetCount(Sample value) const {
+  auto it = sample_counts_.find(value);
+  if (it == sample_counts_.end())
+    return 0;
+  return it->second;
+}
+
+Count SampleMap::TotalCount() const {
+  Count count = 0;
+  for (const auto& entry : sample_counts_) {
+    count += entry.second;
+  }
+  return count;
+}
+
+std::unique_ptr<SampleCountIterator> SampleMap::Iterator() const {
+  return std::make_unique<SampleMapIterator>(sample_counts_);
+}
+
+bool SampleMap::AddSubtractImpl(SampleCountIterator* iter, Operator op) {
+  Sample min;
+  int64_t max;
+  Count count;
+  for (; !iter->Done(); iter->Next()) {
+    iter->Get(&min, &max, &count);
+    if (strict_cast<int64_t>(min) + 1 != max)
+      return false;  // SparseHistogram only supports bucket with size 1.
+
+    sample_counts_[min] += (op == HistogramSamples::ADD) ? count : -count;
+  }
+  return true;
+}
+
+}  // namespace base