Reland the ULONG -> SIZE_T change from 317177
[chromium-blink-merge.git] / base / metrics / user_metrics.cc
blob9db5840ab57052746537bb223a8f6445735d53d9
1 // Copyright 2014 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #include "base/metrics/user_metrics.h"
7 #include <vector>
9 #include "base/lazy_instance.h"
10 #include "base/threading/thread_checker.h"
12 namespace base {
13 namespace {
15 // A helper class for tracking callbacks and ensuring thread-safety.
16 class Callbacks {
17 public:
18 Callbacks() {}
20 // Records the |action|.
21 void Record(const std::string& action) {
22 DCHECK(thread_checker_.CalledOnValidThread());
23 for (size_t i = 0; i < callbacks_.size(); ++i) {
24 callbacks_[i].Run(action);
28 // Adds |callback| to the list of |callbacks_|.
29 void AddCallback(const ActionCallback& callback) {
30 DCHECK(thread_checker_.CalledOnValidThread());
31 callbacks_.push_back(callback);
34 // Removes the first instance of |callback| from the list of |callbacks_|, if
35 // there is one.
36 void RemoveCallback(const ActionCallback& callback) {
37 DCHECK(thread_checker_.CalledOnValidThread());
38 for (size_t i = 0; i < callbacks_.size(); ++i) {
39 if (callbacks_[i].Equals(callback)) {
40 callbacks_.erase(callbacks_.begin() + i);
41 return;
46 private:
47 base::ThreadChecker thread_checker_;
48 std::vector<ActionCallback> callbacks_;
50 DISALLOW_COPY_AND_ASSIGN(Callbacks);
53 base::LazyInstance<Callbacks> g_callbacks = LAZY_INSTANCE_INITIALIZER;
55 } // namespace
57 void RecordAction(const UserMetricsAction& action) {
58 g_callbacks.Get().Record(action.str_);
61 void RecordComputedAction(const std::string& action) {
62 g_callbacks.Get().Record(action);
65 void AddActionCallback(const ActionCallback& callback) {
66 g_callbacks.Get().AddCallback(callback);
69 void RemoveActionCallback(const ActionCallback& callback) {
70 g_callbacks.Get().RemoveCallback(callback);
74 } // namespace base