Update //base to chromium 9659b08ea5a34f889dc4166217f438095ddc10d2

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/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;
 }  // namespace
 
@@ skipping 27 matching lines @@
   }
 
   HistogramBase* histogram_to_delete = NULL;
   HistogramBase* histogram_to_return = NULL;
   {
     base::AutoLock auto_lock(*lock_);
     if (histograms_ == NULL) {
       histogram_to_return = histogram;
     } else {
       const std::string& name = histogram->histogram_name();
-      HistogramMap::iterator it = histograms_->find(name);
+      HistogramMap::iterator it = histograms_->find(HistogramNameRef(name));
       if (histograms_->end() == it) {
-        (*histograms_)[name] = histogram;
+        (*histograms_)[HistogramNameRef(name)] = histogram;
         ANNOTATE_LEAKING_OBJECT_PTR(histogram);  // see crbug.com/79322
+        // If there are callbacks for this histogram, we set the kCallbackExists
+        // flag.
+        auto callback_iterator = callbacks_->find(name);
+        if (callback_iterator != callbacks_->end()) {
+          if (!callback_iterator->second.is_null())
+            histogram->SetFlags(HistogramBase::kCallbackExists);
+          else
+            histogram->ClearFlags(HistogramBase::kCallbackExists);
+        }
         histogram_to_return = histogram;
       } else if (histogram == it->second) {
         // The histogram was registered before.
         histogram_to_return = histogram;
       } else {
         // We already have one histogram with this name.
         histogram_to_return = it->second;
         histogram_to_delete = histogram;
       }
     }
@@ skipping 109 matching lines @@
 
 // static
 void StatisticsRecorder::GetHistograms(Histograms* output) {
   if (lock_ == NULL)
     return;
   base::AutoLock auto_lock(*lock_);
   if (histograms_ == NULL)
     return;
 
   for (const auto& entry : *histograms_) {
-    DCHECK_EQ(entry.first, entry.second->histogram_name());
+    DCHECK_EQ(entry.first.name_, entry.second->histogram_name());
     output->push_back(entry.second);
   }
 }
 
 // static
 void StatisticsRecorder::GetBucketRanges(
     std::vector<const BucketRanges*>* output) {
   if (lock_ == NULL)
     return;
   base::AutoLock auto_lock(*lock_);
   if (ranges_ == NULL)
     return;
 
   for (const auto& entry : *ranges_) {
     for (const auto& range_entry : *entry.second) {
       output->push_back(range_entry);
     }
   }
 }
 
 // static
 HistogramBase* StatisticsRecorder::FindHistogram(const std::string& name) {
   if (lock_ == NULL)
     return NULL;
   base::AutoLock auto_lock(*lock_);
   if (histograms_ == NULL)
     return NULL;
 
-  HistogramMap::iterator it = histograms_->find(name);
+  HistogramMap::iterator it = histograms_->find(HistogramNameRef(name));
   if (histograms_->end() == it)
     return NULL;
   return it->second;
 }
 
+// static
+bool StatisticsRecorder::SetCallback(
+    const std::string& name,
+    const StatisticsRecorder::OnSampleCallback& cb) {
+  DCHECK(!cb.is_null());
+  if (lock_ == NULL)
+    return false;
+  base::AutoLock auto_lock(*lock_);
+  if (histograms_ == NULL)
+    return false;
+
+  if (ContainsKey(*callbacks_, name))
+    return false;
+  callbacks_->insert(std::make_pair(name, cb));
+
+  auto histogram_iterator = histograms_->find(HistogramNameRef(name));
+  if (histogram_iterator != histograms_->end())
+    histogram_iterator->second->SetFlags(HistogramBase::kCallbackExists);
+
+  return true;
+}
+
+// static
+void StatisticsRecorder::ClearCallback(const std::string& name) {
+  if (lock_ == NULL)
+    return;
+  base::AutoLock auto_lock(*lock_);
+  if (histograms_ == NULL)
+    return;
+
+  callbacks_->erase(name);
+
+  // We also clear the flag from the histogram (if it exists).
+  auto histogram_iterator = histograms_->find(HistogramNameRef(name));
+  if (histogram_iterator != histograms_->end())
+    histogram_iterator->second->ClearFlags(HistogramBase::kCallbackExists);
+}
+
+// static
+StatisticsRecorder::OnSampleCallback StatisticsRecorder::FindCallback(
+    const std::string& name) {
+  if (lock_ == NULL)
+    return OnSampleCallback();
+  base::AutoLock auto_lock(*lock_);
+  if (histograms_ == NULL)
+    return OnSampleCallback();
+
+  auto callback_iterator = callbacks_->find(name);
+  return callback_iterator != callbacks_->end() ? callback_iterator->second
+                                                : OnSampleCallback();
+}
+
 // private static
 void StatisticsRecorder::GetSnapshot(const std::string& query,
                                      Histograms* snapshot) {
   if (lock_ == NULL)
     return;
   base::AutoLock auto_lock(*lock_);
   if (histograms_ == NULL)
     return;
 
   for (const auto& entry : *histograms_) {
-    if (entry.first.find(query) != std::string::npos)
+    if (entry.first.name_.find(query) != std::string::npos)
       snapshot->push_back(entry.second);
   }
 }
 
 // This singleton instance should be started during the single threaded portion
 // of main(), and hence it is not thread safe.  It initializes globals to
 // provide support for all future calls.
 StatisticsRecorder::StatisticsRecorder() {
   DCHECK(!histograms_);
   if (lock_ == NULL) {
     // This will leak on purpose. It's the only way to make sure we won't race
     // against the static uninitialization of the module while one of our
     // static methods relying on the lock get called at an inappropriate time
     // during the termination phase. Since it's a static data member, we will
     // leak one per process, which would be similar to the instance allocated
     // during static initialization and released only on  process termination.
     lock_ = new base::Lock;
   }
   base::AutoLock auto_lock(*lock_);
   histograms_ = new HistogramMap;
+  callbacks_ = new CallbackMap;
   ranges_ = new RangesMap;
 
   if (VLOG_IS_ON(1))
     AtExitManager::RegisterCallback(&DumpHistogramsToVlog, this);
 }
 
 // static
 void StatisticsRecorder::DumpHistogramsToVlog(void* instance) {
   std::string output;
   StatisticsRecorder::WriteGraph(std::string(), &output);
   VLOG(1) << output;
 }
 
 StatisticsRecorder::~StatisticsRecorder() {
   DCHECK(histograms_ && ranges_ && lock_);
 
   // Clean up.
   scoped_ptr<HistogramMap> histograms_deleter;
+  scoped_ptr<CallbackMap> callbacks_deleter;
   scoped_ptr<RangesMap> ranges_deleter;
   // We don't delete lock_ on purpose to avoid having to properly protect
   // against it going away after we checked for NULL in the static methods.
   {
     base::AutoLock auto_lock(*lock_);
     histograms_deleter.reset(histograms_);
+    callbacks_deleter.reset(callbacks_);
     ranges_deleter.reset(ranges_);
     histograms_ = NULL;
+    callbacks_ = NULL;
     ranges_ = NULL;
   }
   // We are going to leak the histograms and the ranges.
 }
 
 
 // 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