/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* vim:set ts=2 sw=2 sts=2 et cindent: */ /* This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ #include "mozilla/Logging.h" #include "mozilla/StaticPtr.h" #include "nsContentUtils.h" #include "MediaDecoder.h" #include "MediaShutdownManager.h" namespace mozilla { extern LazyLogModule gMediaDecoderLog; #define DECODER_LOG(type, msg) MOZ_LOG(gMediaDecoderLog, type, msg) NS_IMPL_ISUPPORTS(MediaShutdownManager, nsIAsyncShutdownBlocker) MediaShutdownManager::MediaShutdownManager() { MOZ_ASSERT(NS_IsMainThread()); MOZ_COUNT_CTOR(MediaShutdownManager); } MediaShutdownManager::~MediaShutdownManager() { MOZ_ASSERT(NS_IsMainThread()); MOZ_COUNT_DTOR(MediaShutdownManager); } // Note that we don't use ClearOnShutdown() on this StaticRefPtr, as that // may interfere with our shutdown listener. StaticRefPtr<MediaShutdownManager> MediaShutdownManager::sInstance; MediaShutdownManager& MediaShutdownManager::Instance() { MOZ_ASSERT(NS_IsMainThread()); MOZ_DIAGNOSTIC_ASSERT(sInstance); return *sInstance; } static nsCOMPtr<nsIAsyncShutdownClient> GetShutdownBarrier() { nsCOMPtr<nsIAsyncShutdownService> svc = services::GetAsyncShutdown(); MOZ_RELEASE_ASSERT(svc); nsCOMPtr<nsIAsyncShutdownClient> barrier; nsresult rv = svc->GetProfileBeforeChange(getter_AddRefs(barrier)); if (!barrier) { // We are probably in a content process. We need to do cleanup at // XPCOM shutdown in leakchecking builds. rv = svc->GetXpcomWillShutdown(getter_AddRefs(barrier)); } MOZ_RELEASE_ASSERT(NS_SUCCEEDED(rv)); MOZ_RELEASE_ASSERT(barrier); return barrier.forget(); } void MediaShutdownManager::InitStatics() { MOZ_ASSERT(NS_IsMainThread()); static bool sInitDone = false; if (sInitDone) { return; } sInitDone = true; sInstance = new MediaShutdownManager(); nsresult rv = GetShutdownBarrier()->AddBlocker( sInstance, NS_LITERAL_STRING(__FILE__), __LINE__, NS_LITERAL_STRING("MediaShutdownManager shutdown")); if (NS_FAILED(rv)) { MOZ_CRASH_UNSAFE_PRINTF("Failed to add shutdown blocker! rv=%x", uint32_t(rv)); } } void MediaShutdownManager::RemoveBlocker() { MOZ_ASSERT(NS_IsMainThread()); MOZ_ASSERT(mIsDoingXPCOMShutDown); MOZ_ASSERT(mDecoders.Count() == 0); GetShutdownBarrier()->RemoveBlocker(this); // Clear our singleton reference. This will probably delete // this instance, so don't deref |this| clearing sInstance. sInstance = nullptr; DECODER_LOG(LogLevel::Debug, ("MediaShutdownManager::BlockShutdown() end.")); } nsresult MediaShutdownManager::Register(MediaDecoder* aDecoder) { MOZ_ASSERT(NS_IsMainThread()); if (mIsDoingXPCOMShutDown) { return NS_ERROR_ABORT; } // Don't call Register() after you've Unregistered() all the decoders, // that's not going to work. MOZ_ASSERT(!mDecoders.Contains(aDecoder)); mDecoders.PutEntry(aDecoder); MOZ_ASSERT(mDecoders.Contains(aDecoder)); MOZ_ASSERT(mDecoders.Count() > 0); return NS_OK; } void MediaShutdownManager::Unregister(MediaDecoder* aDecoder) { MOZ_ASSERT(NS_IsMainThread()); if (!mDecoders.Contains(aDecoder)) { return; } mDecoders.RemoveEntry(aDecoder); if (mIsDoingXPCOMShutDown && mDecoders.Count() == 0) { RemoveBlocker(); } } NS_IMETHODIMP MediaShutdownManager::GetName(nsAString& aName) { aName = NS_LITERAL_STRING("MediaShutdownManager: shutdown"); return NS_OK; } NS_IMETHODIMP MediaShutdownManager::GetState(nsIPropertyBag**) { return NS_OK; } NS_IMETHODIMP MediaShutdownManager::BlockShutdown(nsIAsyncShutdownClient*) { MOZ_ASSERT(NS_IsMainThread()); MOZ_ASSERT(sInstance); DECODER_LOG(LogLevel::Debug, ("MediaShutdownManager::BlockShutdown() start...")); // Set this flag to ensure no Register() is allowed when Shutdown() begins. mIsDoingXPCOMShutDown = true; auto oldCount = mDecoders.Count(); if (oldCount == 0) { RemoveBlocker(); return NS_OK; } // Iterate over the decoders and shut them down. for (auto iter = mDecoders.Iter(); !iter.Done(); iter.Next()) { iter.Get()->GetKey()->NotifyXPCOMShutdown(); // Check MediaDecoder::Shutdown doesn't call Unregister() synchronously in // order not to corrupt our hashtable traversal. MOZ_ASSERT(mDecoders.Count() == oldCount); } return NS_OK; } } // namespace mozilla