Sort histograms by name before displaying them.

base/metrics/statistics_recorder.cc

 // 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/statistics_recorder.h"
 
 #include "base/at_exit.h"
 #include "base/debug/leak_annotations.h"
 #include "base/json/string_escape.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/metrics_hashes.h"
 #include "base/stl_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/synchronization/lock.h"
 #include "base/values.h"
 
 namespace {
+
 // Initialize histogram statistics gathering system.
 base::LazyInstance<base::StatisticsRecorder>::Leaky g_statistics_recorder_ =
     LAZY_INSTANCE_INITIALIZER;
+
+bool HistogramNameLesser(const base::HistogramBase* a,
+                         const base::HistogramBase* b) {
+  return a->histogram_name() < b->histogram_name();
+}
+
 }  // namespace
 
 namespace base {
 
 // static
 void StatisticsRecorder::Initialize() {
   // Ensure that an instance of the StatisticsRecorder object is created.
   g_statistics_recorder_.Get();
 }
 
@@ skipping 102 matching lines @@
 }
 
 // static
 void StatisticsRecorder::WriteHTMLGraph(const std::string& query,
                                         std::string* output) {
   if (!IsActive())
     return;
 
   Histograms snapshot;
   GetSnapshot(query, &snapshot);
+  std::sort(snapshot.begin(), snapshot.end(), &HistogramNameLesser);
   for (const HistogramBase* histogram : snapshot) {
     histogram->WriteHTMLGraph(output);
     output->append("<br><hr><br>");
   }
 }
 
 // static
 void StatisticsRecorder::WriteGraph(const std::string& query,
                                     std::string* output) {
   if (!IsActive())
     return;
   if (query.length())
     StringAppendF(output, "Collections of histograms for %s\n", query.c_str());
   else
     output->append("Collections of all histograms\n");
 
   Histograms snapshot;
   GetSnapshot(query, &snapshot);
+  std::sort(snapshot.begin(), snapshot.end(), &HistogramNameLesser);
   for (const HistogramBase* histogram : snapshot) {
     histogram->WriteAscii(output);
     output->append("\n");
   }
 }
 
 // static
 std::string StatisticsRecorder::ToJSON(const std::string& query) {
   if (!IsActive())
     return std::string();
@@ skipping 193 matching lines @@
 // static
 StatisticsRecorder::HistogramMap* StatisticsRecorder::histograms_ = NULL;
 // static
 StatisticsRecorder::CallbackMap* StatisticsRecorder::callbacks_ = NULL;
 // static
 StatisticsRecorder::RangesMap* StatisticsRecorder::ranges_ = NULL;
 // static
 base::Lock* StatisticsRecorder::lock_ = NULL;
 
 }  // namespace base