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Diffstat (limited to 'dom/media/gmp/GMPServiceChild.h')
| -rw-r--r-- | dom/media/gmp/GMPServiceChild.h | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/dom/media/gmp/GMPServiceChild.h b/dom/media/gmp/GMPServiceChild.h new file mode 100644 index 0000000000..2775a83489 --- /dev/null +++ b/dom/media/gmp/GMPServiceChild.h @@ -0,0 +1,164 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* 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/. */ + +#ifndef GMPServiceChild_h_ +#define GMPServiceChild_h_ + +#include "GMPService.h" +#include "MediaResult.h" +#include "base/process.h" +#include "mozilla/dom/PContent.h" +#include "mozilla/gmp/PGMPServiceChild.h" +#include "mozilla/MozPromise.h" +#include "nsIAsyncShutdown.h" +#include "nsRefPtrHashtable.h" + +namespace mozilla::gmp { + +class GMPContentParent; +class GMPServiceChild; + +class GeckoMediaPluginServiceChild : public GeckoMediaPluginService, + public nsIAsyncShutdownBlocker { + friend class GMPServiceChild; + + public: + static already_AddRefed<GeckoMediaPluginServiceChild> GetSingleton(); + nsresult Init() override; + + NS_DECL_ISUPPORTS_INHERITED + NS_DECL_NSIASYNCSHUTDOWNBLOCKER + + NS_IMETHOD HasPluginForAPI(const nsACString& aAPI, + const nsTArray<nsCString>& aTags, + bool* aRetVal) override; + NS_IMETHOD GetNodeId(const nsAString& aOrigin, + const nsAString& aTopLevelOrigin, + const nsAString& aGMPName, + UniquePtr<GetNodeIdCallback>&& aCallback) override; + + NS_DECL_NSIOBSERVER + + void SetServiceChild(RefPtr<GMPServiceChild>&& aServiceChild); + + void RemoveGMPContentParent(GMPContentParent* aGMPContentParent); + + static void UpdateGMPCapabilities( + nsTArray<mozilla::dom::GMPCapabilityData>&& aCapabilities); + + void BeginShutdown(); + + protected: + void InitializePlugins(nsISerialEventTarget*) override { + // Nothing to do here. + } + + RefPtr<GetGMPContentParentPromise> GetContentParent( + GMPCrashHelper* aHelper, const NodeIdVariant& aNodeIdVariant, + const nsACString& aAPI, const nsTArray<nsCString>& aTags) override; + + private: + friend class OpenPGMPServiceChild; + + ~GeckoMediaPluginServiceChild() override; + + typedef MozPromise<GMPServiceChild*, MediaResult, /* IsExclusive = */ true> + GetServiceChildPromise; + RefPtr<GetServiceChildPromise> GetServiceChild(); + + nsTArray<MozPromiseHolder<GetServiceChildPromise>> mGetServiceChildPromises; + RefPtr<GMPServiceChild> mServiceChild; + + // Shutdown blocker management. A shutdown blocker is used to ensure that + // we do not shutdown until all content parents are removed from + // GMPServiceChild::mContentParents. + // + // The following rules let us shutdown block (and thus we shouldn't + // violate them): + // - We will only call GetContentParent if mShuttingDownOnGMPThread is false. + // - mShuttingDownOnGMPThread will become true once profile teardown is + // observed in the parent process (and once GMPServiceChild receives a + // message from GMPServiceParent) or if we block shutdown (which implies + // we're in shutdown). + // - If we currently have mPendingGetContentParents > 0 or parents in + // GMPServiceChild::mContentParents we should block shutdown so such + // parents can be cleanly shutdown. + // therefore + // - We can block shutdown at xpcom-will-shutdown until our content parents + // are handled. + // - Because once mShuttingDownOnGMPThread is true we cannot add new content + // parents, we know that when mShuttingDownOnGMPThread && all content + // parents are handled we'll never add more and it's safe to stop blocking + // shutdown. + // this relies on + // - Once we're shutting down, we need to ensure all content parents are + // shutdown and removed. Failure to do so will result in a shutdown stall. + + // Note that at the time of writing there are significant differences in how + // xpcom shutdown is handled in release and non-release builds. For example, + // in release builds content processes are exited early, so xpcom shutdown + // is not observed (and not blocked by blockers). This is important to keep + // in mind when testing the shutdown blocking machinery (you won't see most + // of it be invoked in release). + + // All of these members should only be used on the GMP thread unless + // otherwise noted! + + // Add a shutdown blocker. Main thread only. Should only be called once when + // we init the service. + nsresult AddShutdownBlocker(); + // Remove a shutdown blocker. Should be called once at most and only when + // mShuttingDownOnGMPThread. Prefer RemoveShutdownBlockerIfNeeded unless + // absolutely certain you need to call this directly. + void RemoveShutdownBlocker(); + // Remove shutdown blocker if the following conditions are met: + // - mShuttingDownOnGMPThread. + // - !mServiceChild->HaveContentParents. + // - mPendingGetContentParents == 0. + // - mShutdownBlockerHasBeenAdded. + void RemoveShutdownBlockerIfNeeded(); + +#ifdef DEBUG + // Track if we've added a shutdown blocker for sanity checking. Main thread + // only. + bool mShutdownBlockerAdded = false; +#endif // DEBUG + // The number of GetContentParent calls that have not yet been resolved or + // rejected. We use this value to help determine if we need to block + // shutdown. Should only be used on GMP thread to avoid races. + uint32_t mPendingGetContentParents = 0; + // End shutdown blocker management. +}; + +class GMPServiceChild : public PGMPServiceChild { + public: + // Mark AddRef and Release as `final`, as they overload pure virtual + // implementations in PGMPServiceChild. + NS_INLINE_DECL_THREADSAFE_REFCOUNTING(GMPServiceChild, final) + + explicit GMPServiceChild() = default; + + already_AddRefed<GMPContentParent> GetBridgedGMPContentParent( + ProcessId aOtherPid, ipc::Endpoint<PGMPContentParent>&& endpoint); + + void RemoveGMPContentParent(GMPContentParent* aGMPContentParent); + + void GetAlreadyBridgedTo(nsTArray<ProcessId>& aAlreadyBridgedTo); + + static bool Create(Endpoint<PGMPServiceChild>&& aGMPService); + + ipc::IPCResult RecvBeginShutdown() override; + + bool HaveContentParents() const; + + private: + ~GMPServiceChild() = default; + + nsRefPtrHashtable<nsUint64HashKey, GMPContentParent> mContentParents; +}; + +} // namespace mozilla::gmp + +#endif // GMPServiceChild_h_ |