michael@0: // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
michael@0: // Use of this source code is governed by a BSD-style license that can be
michael@0: // found in the LICENSE file.
michael@0: 
michael@0: #include "chrome/common/notification_service.h"
michael@0: 
michael@0: #include "base/lazy_instance.h"
michael@0: #include "base/thread_local.h"
michael@0: 
michael@0: static base::LazyInstance<base::ThreadLocalPointer<NotificationService> >
michael@0:     lazy_tls_ptr(base::LINKER_INITIALIZED);
michael@0: 
michael@0: // static
michael@0: NotificationService* NotificationService::current() {
michael@0:   return lazy_tls_ptr.Pointer()->Get();
michael@0: }
michael@0: 
michael@0: // static
michael@0: bool NotificationService::HasKey(const NotificationSourceMap& map,
michael@0:                                  const NotificationSource& source) {
michael@0:   return map.find(source.map_key()) != map.end();
michael@0: }
michael@0: 
michael@0: NotificationService::NotificationService() {
michael@0:   DCHECK(current() == NULL);
michael@0: #ifndef NDEBUG
michael@0:   memset(observer_counts_, 0, sizeof(observer_counts_));
michael@0: #endif
michael@0: 
michael@0:   lazy_tls_ptr.Pointer()->Set(this);
michael@0: }
michael@0: 
michael@0: void NotificationService::AddObserver(NotificationObserver* observer,
michael@0:                                       NotificationType type,
michael@0:                                       const NotificationSource& source) {
michael@0:   DCHECK(type.value < NotificationType::NOTIFICATION_TYPE_COUNT);
michael@0: 
michael@0:   // We have gotten some crashes where the observer pointer is NULL. The problem
michael@0:   // is that this happens when we actually execute a notification, so have no
michael@0:   // way of knowing who the bad observer was. We want to know when this happens
michael@0:   // in release mode so we know what code to blame the crash on (since this is
michael@0:   // guaranteed to crash later).
michael@0:   CHECK(observer);
michael@0: 
michael@0:   NotificationObserverList* observer_list;
michael@0:   if (HasKey(observers_[type.value], source)) {
michael@0:     observer_list = observers_[type.value][source.map_key()];
michael@0:   } else {
michael@0:     observer_list = new NotificationObserverList;
michael@0:     observers_[type.value][source.map_key()] = observer_list;
michael@0:   }
michael@0: 
michael@0:   observer_list->AddObserver(observer);
michael@0: #ifndef NDEBUG
michael@0:   ++observer_counts_[type.value];
michael@0: #endif
michael@0: }
michael@0: 
michael@0: void NotificationService::RemoveObserver(NotificationObserver* observer,
michael@0:                                          NotificationType type,
michael@0:                                          const NotificationSource& source) {
michael@0:   DCHECK(type.value < NotificationType::NOTIFICATION_TYPE_COUNT);
michael@0:   DCHECK(HasKey(observers_[type.value], source));
michael@0: 
michael@0:   NotificationObserverList* observer_list =
michael@0:       observers_[type.value][source.map_key()];
michael@0:   if (observer_list) {
michael@0:     observer_list->RemoveObserver(observer);
michael@0: #ifndef NDEBUG
michael@0:     --observer_counts_[type.value];
michael@0: #endif
michael@0:   }
michael@0: 
michael@0:   // TODO(jhughes): Remove observer list from map if empty?
michael@0: }
michael@0: 
michael@0: void NotificationService::Notify(NotificationType type,
michael@0:                                  const NotificationSource& source,
michael@0:                                  const NotificationDetails& details) {
michael@0:   DCHECK(type.value > NotificationType::ALL) <<
michael@0:       "Allowed for observing, but not posting.";
michael@0:   DCHECK(type.value < NotificationType::NOTIFICATION_TYPE_COUNT);
michael@0: 
michael@0:   // There's no particular reason for the order in which the different
michael@0:   // classes of observers get notified here.
michael@0: 
michael@0:   // Notify observers of all types and all sources
michael@0:   if (HasKey(observers_[NotificationType::ALL], AllSources()) &&
michael@0:       source != AllSources()) {
michael@0:     FOR_EACH_OBSERVER(NotificationObserver,
michael@0:        *observers_[NotificationType::ALL][AllSources().map_key()],
michael@0:        Observe(type, source, details));
michael@0:   }
michael@0: 
michael@0:   // Notify observers of all types and the given source
michael@0:   if (HasKey(observers_[NotificationType::ALL], source)) {
michael@0:     FOR_EACH_OBSERVER(NotificationObserver,
michael@0:         *observers_[NotificationType::ALL][source.map_key()],
michael@0:         Observe(type, source, details));
michael@0:   }
michael@0: 
michael@0:   // Notify observers of the given type and all sources
michael@0:   if (HasKey(observers_[type.value], AllSources()) &&
michael@0:       source != AllSources()) {
michael@0:     FOR_EACH_OBSERVER(NotificationObserver,
michael@0:                       *observers_[type.value][AllSources().map_key()],
michael@0:                       Observe(type, source, details));
michael@0:   }
michael@0: 
michael@0:   // Notify observers of the given type and the given source
michael@0:   if (HasKey(observers_[type.value], source)) {
michael@0:     FOR_EACH_OBSERVER(NotificationObserver,
michael@0:                       *observers_[type.value][source.map_key()],
michael@0:                       Observe(type, source, details));
michael@0:   }
michael@0: }
michael@0: 
michael@0: 
michael@0: NotificationService::~NotificationService() {
michael@0:   lazy_tls_ptr.Pointer()->Set(NULL);
michael@0: 
michael@0: #ifndef NDEBUG
michael@0:   for (int i = 0; i < NotificationType::NOTIFICATION_TYPE_COUNT; i++) {
michael@0:     if (observer_counts_[i] > 0) {
michael@0:       // This may not be completely fixable -- see
michael@0:       // http://code.google.com/p/chromium/issues/detail?id=11010 .
michael@0:       // But any new leaks should be fixed.
michael@0:       CHROMIUM_LOG(WARNING) << observer_counts_[i] << " notification observer(s) leaked"
michael@0:                             << " of notification type " << i;
michael@0:     }
michael@0:   }
michael@0: #endif
michael@0: 
michael@0:   for (int i = 0; i < NotificationType::NOTIFICATION_TYPE_COUNT; i++) {
michael@0:     NotificationSourceMap omap = observers_[i];
michael@0:     for (NotificationSourceMap::iterator it = omap.begin();
michael@0:          it != omap.end(); ++it) {
michael@0:       delete it->second;
michael@0:     }
michael@0:   }
michael@0: }
michael@0: 
michael@0: NotificationObserver::~NotificationObserver() {}