summaryrefslogtreecommitdiffstats
path: root/third_party/libwebrtc/api/notifier.h
diff options
context:
space:
mode:
Diffstat (limited to 'third_party/libwebrtc/api/notifier.h')
-rw-r--r--third_party/libwebrtc/api/notifier.h68
1 files changed, 68 insertions, 0 deletions
diff --git a/third_party/libwebrtc/api/notifier.h b/third_party/libwebrtc/api/notifier.h
new file mode 100644
index 0000000000..fc2480e00a
--- /dev/null
+++ b/third_party/libwebrtc/api/notifier.h
@@ -0,0 +1,68 @@
+/*
+ * Copyright 2011 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef API_NOTIFIER_H_
+#define API_NOTIFIER_H_
+
+#include <list>
+
+#include "api/media_stream_interface.h"
+#include "api/sequence_checker.h"
+#include "rtc_base/checks.h"
+#include "rtc_base/system/no_unique_address.h"
+
+namespace webrtc {
+
+// Implements a template version of a notifier.
+// TODO(deadbeef): This is an implementation detail; move out of api/.
+template <class T>
+class Notifier : public T {
+ public:
+ Notifier() { sequence_checker_.Detach(); }
+
+ virtual void RegisterObserver(ObserverInterface* observer) {
+ RTC_DCHECK_RUN_ON(&sequence_checker_);
+ RTC_DCHECK(observer != nullptr);
+ observers_.push_back(observer);
+ }
+
+ virtual void UnregisterObserver(ObserverInterface* observer) {
+ RTC_DCHECK_RUN_ON(&sequence_checker_);
+ for (std::list<ObserverInterface*>::iterator it = observers_.begin();
+ it != observers_.end(); it++) {
+ if (*it == observer) {
+ observers_.erase(it);
+ break;
+ }
+ }
+ }
+
+ void FireOnChanged() {
+ RTC_DCHECK_RUN_ON(&sequence_checker_);
+ // Copy the list of observers to avoid a crash if the observer object
+ // unregisters as a result of the OnChanged() call. If the same list is used
+ // UnregisterObserver will affect the list make the iterator invalid.
+ std::list<ObserverInterface*> observers = observers_;
+ for (std::list<ObserverInterface*>::iterator it = observers.begin();
+ it != observers.end(); ++it) {
+ (*it)->OnChanged();
+ }
+ }
+
+ protected:
+ std::list<ObserverInterface*> observers_ RTC_GUARDED_BY(sequence_checker_);
+
+ private:
+ RTC_NO_UNIQUE_ADDRESS SequenceChecker sequence_checker_;
+};
+
+} // namespace webrtc
+
+#endif // API_NOTIFIER_H_