content/media/MediaShutdownManager.cpp

Wed, 31 Dec 2014 06:09:35 +0100

author
Michael Schloh von Bennewitz <michael@schloh.com>
date
Wed, 31 Dec 2014 06:09:35 +0100
changeset 0
6474c204b198
permissions
-rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

michael@0 1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0 2 /* vim:set ts=2 sw=2 sts=2 et cindent: */
michael@0 3 /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0 4 * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0 5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0 6
michael@0 7 #include "MediaShutdownManager.h"
michael@0 8 #include "nsContentUtils.h"
michael@0 9 #include "mozilla/StaticPtr.h"
michael@0 10 #include "MediaDecoder.h"
michael@0 11 #include "SharedThreadPool.h"
michael@0 12 #include "prlog.h"
michael@0 13
michael@0 14 namespace mozilla {
michael@0 15
michael@0 16 #ifdef PR_LOGGING
michael@0 17 extern PRLogModuleInfo* gMediaDecoderLog;
michael@0 18 #define DECODER_LOG(type, msg) PR_LOG(gMediaDecoderLog, type, msg)
michael@0 19 #else
michael@0 20 #define DECODER_LOG(type, msg)
michael@0 21 #endif
michael@0 22
michael@0 23 NS_IMPL_ISUPPORTS(MediaShutdownManager, nsIObserver)
michael@0 24
michael@0 25 MediaShutdownManager::MediaShutdownManager()
michael@0 26 : mIsObservingShutdown(false),
michael@0 27 mIsDoingXPCOMShutDown(false)
michael@0 28 {
michael@0 29 MOZ_ASSERT(NS_IsMainThread());
michael@0 30 MOZ_COUNT_CTOR(MediaShutdownManager);
michael@0 31 }
michael@0 32
michael@0 33 MediaShutdownManager::~MediaShutdownManager()
michael@0 34 {
michael@0 35 MOZ_ASSERT(NS_IsMainThread());
michael@0 36 MOZ_COUNT_DTOR(MediaShutdownManager);
michael@0 37 }
michael@0 38
michael@0 39 // Note that we don't use ClearOnShutdown() on this StaticRefPtr, as that
michael@0 40 // may interfere with our shutdown listener.
michael@0 41 StaticRefPtr<MediaShutdownManager> MediaShutdownManager::sInstance;
michael@0 42
michael@0 43 MediaShutdownManager&
michael@0 44 MediaShutdownManager::Instance()
michael@0 45 {
michael@0 46 MOZ_ASSERT(NS_IsMainThread());
michael@0 47 if (!sInstance) {
michael@0 48 sInstance = new MediaShutdownManager();
michael@0 49 }
michael@0 50 return *sInstance;
michael@0 51 }
michael@0 52
michael@0 53 void
michael@0 54 MediaShutdownManager::EnsureCorrectShutdownObserverState()
michael@0 55 {
michael@0 56 MOZ_ASSERT(!mIsDoingXPCOMShutDown);
michael@0 57 bool needShutdownObserver = mDecoders.Count() > 0;
michael@0 58 if (needShutdownObserver != mIsObservingShutdown) {
michael@0 59 mIsObservingShutdown = needShutdownObserver;
michael@0 60 if (mIsObservingShutdown) {
michael@0 61 nsContentUtils::RegisterShutdownObserver(this);
michael@0 62 } else {
michael@0 63 nsContentUtils::UnregisterShutdownObserver(this);
michael@0 64 // Clear our singleton reference. This will probably delete
michael@0 65 // this instance, so don't deref |this| clearing sInstance.
michael@0 66 sInstance = nullptr;
michael@0 67 }
michael@0 68 }
michael@0 69 }
michael@0 70
michael@0 71 void
michael@0 72 MediaShutdownManager::Register(MediaDecoder* aDecoder)
michael@0 73 {
michael@0 74 MOZ_ASSERT(NS_IsMainThread());
michael@0 75 // Don't call Register() after you've Unregistered() all the decoders,
michael@0 76 // that's not going to work.
michael@0 77 MOZ_ASSERT(!mDecoders.Contains(aDecoder));
michael@0 78 mDecoders.PutEntry(aDecoder);
michael@0 79 MOZ_ASSERT(mDecoders.Contains(aDecoder));
michael@0 80 MOZ_ASSERT(mDecoders.Count() > 0);
michael@0 81 EnsureCorrectShutdownObserverState();
michael@0 82 }
michael@0 83
michael@0 84 void
michael@0 85 MediaShutdownManager::Unregister(MediaDecoder* aDecoder)
michael@0 86 {
michael@0 87 MOZ_ASSERT(NS_IsMainThread());
michael@0 88 MOZ_ASSERT(mDecoders.Contains(aDecoder));
michael@0 89 if (!mIsDoingXPCOMShutDown) {
michael@0 90 mDecoders.RemoveEntry(aDecoder);
michael@0 91 EnsureCorrectShutdownObserverState();
michael@0 92 }
michael@0 93 }
michael@0 94
michael@0 95 NS_IMETHODIMP
michael@0 96 MediaShutdownManager::Observe(nsISupports *aSubjet,
michael@0 97 const char *aTopic,
michael@0 98 const char16_t *someData)
michael@0 99 {
michael@0 100 MOZ_ASSERT(NS_IsMainThread());
michael@0 101 if (strcmp(aTopic, NS_XPCOM_SHUTDOWN_OBSERVER_ID) == 0) {
michael@0 102 Shutdown();
michael@0 103 }
michael@0 104 return NS_OK;
michael@0 105 }
michael@0 106
michael@0 107 static PLDHashOperator
michael@0 108 ShutdownMediaDecoder(nsRefPtrHashKey<MediaDecoder>* aEntry, void*)
michael@0 109 {
michael@0 110 aEntry->GetKey()->Shutdown();
michael@0 111 return PL_DHASH_REMOVE;
michael@0 112 }
michael@0 113
michael@0 114 void
michael@0 115 MediaShutdownManager::Shutdown()
michael@0 116 {
michael@0 117 MOZ_ASSERT(NS_IsMainThread());
michael@0 118 MOZ_ASSERT(sInstance);
michael@0 119
michael@0 120 DECODER_LOG(PR_LOG_DEBUG, ("MediaShutdownManager::Shutdown() start..."));
michael@0 121
michael@0 122 // Mark that we're shutting down, so that Unregister(*) calls don't remove
michael@0 123 // hashtable entries. If Unregsiter(*) was to remove from the hash table,
michael@0 124 // the iterations over the hashtables below would be disrupted.
michael@0 125 mIsDoingXPCOMShutDown = true;
michael@0 126
michael@0 127 // Iterate over the decoders and shut them down, and remove them from the
michael@0 128 // hashtable.
michael@0 129 mDecoders.EnumerateEntries(ShutdownMediaDecoder, nullptr);
michael@0 130
michael@0 131 // Ensure all media shared thread pools are shutdown. This joins with all
michael@0 132 // threads in the state machine thread pool, the decoder thread pool, and
michael@0 133 // any others.
michael@0 134 SharedThreadPool::SpinUntilShutdown();
michael@0 135
michael@0 136 // Remove the MediaShutdownManager instance from the shutdown observer
michael@0 137 // list.
michael@0 138 nsContentUtils::UnregisterShutdownObserver(this);
michael@0 139
michael@0 140 // Clear the singleton instance. The only remaining reference should be the
michael@0 141 // reference that the observer service used to call us with. The
michael@0 142 // MediaShutdownManager will be deleted once the observer service cleans
michael@0 143 // up after it finishes its notifications.
michael@0 144 sInstance = nullptr;
michael@0 145
michael@0 146 DECODER_LOG(PR_LOG_DEBUG, ("MediaShutdownManager::Shutdown() end."));
michael@0 147 }
michael@0 148
michael@0 149 } // namespace mozilla

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