// 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/sparse_histogram.h" #include "base/metrics/sample_map.h" #include "base/metrics/statistics_recorder.h" #include "base/pickle.h" #include "base/strings/stringprintf.h" #include "base/synchronization/lock.h" using std::map; using std::string; namespace base { typedef HistogramBase::Count Count; typedef HistogramBase::Sample Sample; // static HistogramBase* SparseHistogram::FactoryGet(const string& name, int32 flags) { HistogramBase* histogram = StatisticsRecorder::FindHistogram(name); if (!histogram) { // To avoid racy destruction at shutdown, the following will be leaked. HistogramBase* tentative_histogram = new SparseHistogram(name); tentative_histogram->SetFlags(flags); histogram = StatisticsRecorder::RegisterOrDeleteDuplicate(tentative_histogram); } DCHECK_EQ(SPARSE_HISTOGRAM, histogram->GetHistogramType()); return histogram; } SparseHistogram::~SparseHistogram() {} HistogramType SparseHistogram::GetHistogramType() const { return SPARSE_HISTOGRAM; } bool SparseHistogram::HasConstructionArguments( Sample expected_minimum, Sample expected_maximum, size_t expected_bucket_count) const { // SparseHistogram never has min/max/bucket_count limit. return false; } void SparseHistogram::Add(Sample value) { base::AutoLock auto_lock(lock_); samples_.Accumulate(value, 1); } scoped_ptr SparseHistogram::SnapshotSamples() const { scoped_ptr snapshot(new SampleMap()); base::AutoLock auto_lock(lock_); snapshot->Add(samples_); return snapshot.PassAs(); } void SparseHistogram::AddSamples(const HistogramSamples& samples) { base::AutoLock auto_lock(lock_); samples_.Add(samples); } bool SparseHistogram::AddSamplesFromPickle(PickleIterator* iter) { base::AutoLock auto_lock(lock_); return samples_.AddFromPickle(iter); } void SparseHistogram::WriteHTMLGraph(string* output) const { output->append("
");
  WriteAsciiImpl(true, "
", output); output->append("
"); } void SparseHistogram::WriteAscii(string* output) const { WriteAsciiImpl(true, "\n", output); } bool SparseHistogram::SerializeInfoImpl(Pickle* pickle) const { return pickle->WriteString(histogram_name()) && pickle->WriteInt(flags()); } SparseHistogram::SparseHistogram(const string& name) : HistogramBase(name) {} HistogramBase* SparseHistogram::DeserializeInfoImpl(PickleIterator* iter) { string histogram_name; int flags; if (!iter->ReadString(&histogram_name) || !iter->ReadInt(&flags)) { DLOG(ERROR) << "Pickle error decoding Histogram: " << histogram_name; return NULL; } DCHECK(flags & HistogramBase::kIPCSerializationSourceFlag); flags &= ~HistogramBase::kIPCSerializationSourceFlag; return SparseHistogram::FactoryGet(histogram_name, flags); } void SparseHistogram::GetParameters(DictionaryValue* params) const { // TODO(kaiwang): Implement. (See HistogramBase::WriteJSON.) } void SparseHistogram::GetCountAndBucketData(Count* count, int64* sum, ListValue* buckets) const { // TODO(kaiwang): Implement. (See HistogramBase::WriteJSON.) } void SparseHistogram::WriteAsciiImpl(bool graph_it, const std::string& newline, std::string* output) const { // Get a local copy of the data so we are consistent. scoped_ptr snapshot = SnapshotSamples(); Count total_count = snapshot->TotalCount(); double scaled_total_count = total_count / 100.0; WriteAsciiHeader(total_count, output); output->append(newline); // Determine how wide the largest bucket range is (how many digits to print), // so that we'll be able to right-align starts for the graphical bars. // Determine which bucket has the largest sample count so that we can // normalize the graphical bar-width relative to that sample count. Count largest_count = 0; Sample largest_sample = 0; scoped_ptr it = snapshot->Iterator(); while (!it->Done()) { Sample min; Sample max; Count count; it->Get(&min, &max, &count); if (min > largest_sample) largest_sample = min; if (count > largest_count) largest_count = count; it->Next(); } size_t print_width = GetSimpleAsciiBucketRange(largest_sample).size() + 1; // iterate over each item and display them it = snapshot->Iterator(); while (!it->Done()) { Sample min; Sample max; Count count; it->Get(&min, &max, &count); // value is min, so display it string range = GetSimpleAsciiBucketRange(min); output->append(range); for (size_t j = 0; range.size() + j < print_width + 1; ++j) output->push_back(' '); if (graph_it) WriteAsciiBucketGraph(count, largest_count, output); WriteAsciiBucketValue(count, scaled_total_count, output); output->append(newline); it->Next(); } } void SparseHistogram::WriteAsciiHeader(const Count total_count, std::string* output) const { StringAppendF(output, "Histogram: %s recorded %d samples", histogram_name().c_str(), total_count); if (flags() & ~kHexRangePrintingFlag) StringAppendF(output, " (flags = 0x%x)", flags() & ~kHexRangePrintingFlag); } } // namespace base