From 5b45981df55a85a45adc2992cc6ddaba2c862b70 Mon Sep 17 00:00:00 2001
From: Chris Pearce <cpearce@mozilla.com>
Date: Tue, 5 Aug 2014 10:18:31 +1200
Subject: [PATCH] Bug 1048107 - Add GMPTimer implementation and placeholder GMP
 clock. r=jesup

---
 content/media/gmp/GMPChild.cpp           | 29 +++++++-
 content/media/gmp/GMPChild.h             |  9 +++
 content/media/gmp/GMPDecryptorChild.h    |  2 +-
 content/media/gmp/GMPParent.cpp          | 25 ++++++-
 content/media/gmp/GMPParent.h            |  7 +-
 content/media/gmp/GMPPlatform.cpp        | 28 +++++++-
 content/media/gmp/GMPPlatform.h          |  4 +-
 content/media/gmp/GMPTimerChild.cpp      | 67 ++++++++++++++++++
 content/media/gmp/GMPTimerChild.h        | 46 +++++++++++++
 content/media/gmp/GMPTimerParent.cpp     | 88 ++++++++++++++++++++++++
 content/media/gmp/GMPTimerParent.h       | 61 ++++++++++++++++
 content/media/gmp/PGMP.ipdl              |  3 +
 content/media/gmp/PGMPTimer.ipdl         | 22 ++++++
 content/media/gmp/gmp-api/gmp-platform.h |  2 +
 content/media/gmp/moz.build              |  5 ++
 15 files changed, 390 insertions(+), 8 deletions(-)
 create mode 100644 content/media/gmp/GMPTimerChild.cpp
 create mode 100644 content/media/gmp/GMPTimerChild.h
 create mode 100644 content/media/gmp/GMPTimerParent.cpp
 create mode 100644 content/media/gmp/GMPTimerParent.h
 create mode 100644 content/media/gmp/PGMPTimer.ipdl

diff --git a/content/media/gmp/GMPChild.cpp b/content/media/gmp/GMPChild.cpp
index 0adf7034e7e2..f24dcd7144ff 100644
--- a/content/media/gmp/GMPChild.cpp
+++ b/content/media/gmp/GMPChild.cpp
@@ -110,7 +110,7 @@ GMPChild::LoadPluginLibrary(const std::string& aPluginPath)
   }
 
   auto platformAPI = new GMPPlatformAPI();
-  InitPlatformAPI(*platformAPI);
+  InitPlatformAPI(*platformAPI, this);
 
   if (initFunc(platformAPI) != GMPNoErr) {
     return false;
@@ -301,6 +301,33 @@ GMPChild::RecvPGMPDecryptorConstructor(PGMPDecryptorChild* aActor)
   return true;
 }
 
+PGMPTimerChild*
+GMPChild::AllocPGMPTimerChild()
+{
+  return new GMPTimerChild(this);
+}
+
+bool
+GMPChild::DeallocPGMPTimerChild(PGMPTimerChild* aActor)
+{
+  MOZ_ASSERT(mTimerChild == static_cast<GMPTimerChild*>(aActor));
+  mTimerChild = nullptr;
+  return true;
+}
+
+GMPTimerChild*
+GMPChild::GetGMPTimers()
+{
+  if (!mTimerChild) {
+    PGMPTimerChild* sc = SendPGMPTimerConstructor();
+    if (!sc) {
+      return nullptr;
+    }
+    mTimerChild = static_cast<GMPTimerChild*>(sc);
+  }
+  return mTimerChild;
+}
+
 bool
 GMPChild::RecvCrashPluginNow()
 {
diff --git a/content/media/gmp/GMPChild.h b/content/media/gmp/GMPChild.h
index 93c054d7bcdf..dd453cde4050 100644
--- a/content/media/gmp/GMPChild.h
+++ b/content/media/gmp/GMPChild.h
@@ -8,6 +8,7 @@
 
 #include "mozilla/gmp/PGMPChild.h"
 #include "GMPSharedMemManager.h"
+#include "GMPTimerChild.h"
 #include "gmp-entrypoints.h"
 #include "prlink.h"
 
@@ -28,6 +29,9 @@ public:
   bool LoadPluginLibrary(const std::string& aPluginPath);
   MessageLoop* GMPMessageLoop();
 
+  // Main thread only.
+  GMPTimerChild* GetGMPTimers();
+
   // GMPSharedMem
   virtual void CheckThread() MOZ_OVERRIDE;
 
@@ -51,11 +55,16 @@ private:
   virtual bool DeallocPGMPAudioDecoderChild(PGMPAudioDecoderChild* aActor) MOZ_OVERRIDE;
   virtual bool RecvPGMPAudioDecoderConstructor(PGMPAudioDecoderChild* aActor) MOZ_OVERRIDE;
 
+  virtual PGMPTimerChild* AllocPGMPTimerChild() MOZ_OVERRIDE;
+  virtual bool DeallocPGMPTimerChild(PGMPTimerChild* aActor) MOZ_OVERRIDE;
+
   virtual bool RecvCrashPluginNow() MOZ_OVERRIDE;
 
   virtual void ActorDestroy(ActorDestroyReason aWhy) MOZ_OVERRIDE;
   virtual void ProcessingError(Result aWhat) MOZ_OVERRIDE;
 
+  nsRefPtr<GMPTimerChild> mTimerChild;
+
   PRLibrary* mLib;
   GMPGetAPIFunc mGetAPIFunc;
   MessageLoop* mGMPMessageLoop;
diff --git a/content/media/gmp/GMPDecryptorChild.h b/content/media/gmp/GMPDecryptorChild.h
index ecc6229f50e4..6e9a9eb4a886 100644
--- a/content/media/gmp/GMPDecryptorChild.h
+++ b/content/media/gmp/GMPDecryptorChild.h
@@ -120,7 +120,7 @@ private:
 
 #ifdef DEBUG
   GMPChild* mPlugin;
-#endif           
+#endif
 };
 
 } // namespace gmp
diff --git a/content/media/gmp/GMPParent.cpp b/content/media/gmp/GMPParent.cpp
index 791a333b71f6..b3a6e149e4ce 100644
--- a/content/media/gmp/GMPParent.cpp
+++ b/content/media/gmp/GMPParent.cpp
@@ -16,6 +16,7 @@
 #include "mozIGeckoMediaPluginService.h"
 #include "mozilla/unused.h"
 #include "nsIObserverService.h"
+#include "GMPTimerParent.h"
 #include "runnable_utils.h"
 
 #include "mozilla/dom/CrashReporterParent.h"
@@ -92,7 +93,7 @@ GMPParent::Init(GeckoMediaPluginService *aService, nsIFile* aPluginDir)
   if (NS_FAILED(rv)) {
     return rv;
   }
-  LOGD(("%s::%s: %p for %s", __CLASS__, __FUNCTION__, this, 
+  LOGD(("%s::%s: %p for %s", __CLASS__, __FUNCTION__, this,
        NS_LossyConvertUTF16toASCII(leafname).get()));
 
   MOZ_ASSERT(leafname.Length() > 4);
@@ -618,6 +619,28 @@ GMPParent::DeallocPGMPAudioDecoderParent(PGMPAudioDecoderParent* aActor)
   return true;
 }
 
+bool
+GMPParent::RecvPGMPTimerConstructor(PGMPTimerParent* actor)
+{
+  return true;
+}
+
+PGMPTimerParent*
+GMPParent::AllocPGMPTimerParent()
+{
+  GMPTimerParent* p = new GMPTimerParent(GMPThread());
+  NS_ADDREF(p); // Released in DeallocPGMPTimerParent.
+  return p;
+}
+
+bool
+GMPParent::DeallocPGMPTimerParent(PGMPTimerParent* aActor)
+{
+  GMPTimerParent* p = static_cast<GMPTimerParent*>(aActor);
+  NS_RELEASE(p);
+  return true;
+}
+
 nsresult
 ParseNextRecord(nsILineInputStream* aLineInputStream,
                 const nsCString& aPrefix,
diff --git a/content/media/gmp/GMPParent.h b/content/media/gmp/GMPParent.h
index d513b82aebfa..f215f899e059 100644
--- a/content/media/gmp/GMPParent.h
+++ b/content/media/gmp/GMPParent.h
@@ -12,6 +12,7 @@
 #include "GMPDecryptorParent.h"
 #include "GMPVideoDecoderParent.h"
 #include "GMPVideoEncoderParent.h"
+#include "GMPTimerParent.h"
 #include "mozilla/gmp/PGMPParent.h"
 #include "nsCOMPtr.h"
 #include "nscore.h"
@@ -143,7 +144,7 @@ private:
 
   virtual PGMPVideoDecoderParent* AllocPGMPVideoDecoderParent() MOZ_OVERRIDE;
   virtual bool DeallocPGMPVideoDecoderParent(PGMPVideoDecoderParent* aActor) MOZ_OVERRIDE;
-  
+
   virtual PGMPVideoEncoderParent* AllocPGMPVideoEncoderParent() MOZ_OVERRIDE;
   virtual bool DeallocPGMPVideoEncoderParent(PGMPVideoEncoderParent* aActor) MOZ_OVERRIDE;
 
@@ -153,6 +154,10 @@ private:
   virtual PGMPAudioDecoderParent* AllocPGMPAudioDecoderParent() MOZ_OVERRIDE;
   virtual bool DeallocPGMPAudioDecoderParent(PGMPAudioDecoderParent* aActor) MOZ_OVERRIDE;
 
+  virtual bool RecvPGMPTimerConstructor(PGMPTimerParent* actor) MOZ_OVERRIDE;
+  virtual PGMPTimerParent* AllocPGMPTimerParent() MOZ_OVERRIDE;
+  virtual bool DeallocPGMPTimerParent(PGMPTimerParent* aActor) MOZ_OVERRIDE;
+
   GMPState mState;
   nsCOMPtr<nsIFile> mDirectory; // plugin directory on disk
   nsString mName; // base name of plugin on disk, UTF-16 because used for paths
diff --git a/content/media/gmp/GMPPlatform.cpp b/content/media/gmp/GMPPlatform.cpp
index 82ee879d4601..e58b7bd3eb49 100644
--- a/content/media/gmp/GMPPlatform.cpp
+++ b/content/media/gmp/GMPPlatform.cpp
@@ -4,13 +4,17 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "GMPPlatform.h"
+#include "GMPTimerChild.h"
 #include "mozilla/Monitor.h"
 #include "nsAutoPtr.h"
+#include "GMPChild.h"
+#include <ctime>
 
 namespace mozilla {
 namespace gmp {
 
 static MessageLoop* sMainLoop = nullptr;
+static GMPChild* sChild = nullptr;
 
 // We just need a refcounted wrapper for GMPTask objects.
 class Runnable MOZ_FINAL
@@ -141,12 +145,30 @@ CreateMutex(GMPMutex** aMutex)
   return GMPNoErr;
 }
 
+GMPErr
+SetTimerOnMainThread(GMPTask* aTask, int64_t aTimeoutMS)
+{
+  GMPTimerChild* timers = sChild->GetGMPTimers();
+  NS_ENSURE_TRUE(timers, GMPGenericErr);
+  return timers->SetTimer(aTask, aTimeoutMS);
+}
+
+GMPErr
+GetClock(GMPTimestamp* aOutTime)
+{
+  *aOutTime = time(0) * 1000;
+  return GMPNoErr;
+}
+
 void
-InitPlatformAPI(GMPPlatformAPI& aPlatformAPI)
+InitPlatformAPI(GMPPlatformAPI& aPlatformAPI, GMPChild* aChild)
 {
   if (!sMainLoop) {
     sMainLoop = MessageLoop::current();
   }
+  if (!sChild) {
+    sChild = aChild;
+  }
 
   aPlatformAPI.version = 0;
   aPlatformAPI.createthread = &CreateThread;
@@ -154,8 +176,8 @@ InitPlatformAPI(GMPPlatformAPI& aPlatformAPI)
   aPlatformAPI.syncrunonmainthread = &SyncRunOnMainThread;
   aPlatformAPI.createmutex = &CreateMutex;
   aPlatformAPI.createrecord = nullptr;
-  aPlatformAPI.settimer = nullptr;
-  aPlatformAPI.getcurrenttime = nullptr;
+  aPlatformAPI.settimer = &SetTimerOnMainThread;
+  aPlatformAPI.getcurrenttime = &GetClock;
 }
 
 GMPThreadImpl::GMPThreadImpl()
diff --git a/content/media/gmp/GMPPlatform.h b/content/media/gmp/GMPPlatform.h
index 5d0051f6fce2..9323d53d91dc 100644
--- a/content/media/gmp/GMPPlatform.h
+++ b/content/media/gmp/GMPPlatform.h
@@ -15,7 +15,9 @@ namespace gmp {
 
 class GMPChild;
 
-void InitPlatformAPI(GMPPlatformAPI& aPlatformAPI);
+void InitPlatformAPI(GMPPlatformAPI& aPlatformAPI, GMPChild* aChild);
+
+GMPErr RunOnMainThread(GMPTask* aTask);
 
 class GMPThreadImpl : public GMPThread
 {
diff --git a/content/media/gmp/GMPTimerChild.cpp b/content/media/gmp/GMPTimerChild.cpp
new file mode 100644
index 000000000000..0b2b55c79e14
--- /dev/null
+++ b/content/media/gmp/GMPTimerChild.cpp
@@ -0,0 +1,67 @@
+/* -*- 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/. */
+
+#include "GMPTimerChild.h"
+#include "GMPPlatform.h"
+#include "GMPChild.h"
+
+#define MAX_NUM_TIMERS 1000
+
+namespace mozilla {
+namespace gmp {
+
+GMPTimerChild::GMPTimerChild(GMPChild* aPlugin)
+  : mTimerCount(1)
+  , mPlugin(aPlugin)
+{
+  MOZ_ASSERT(mPlugin->GMPMessageLoop() == MessageLoop::current());
+}
+
+GMPTimerChild::~GMPTimerChild()
+{
+  MOZ_ASSERT(mPlugin->GMPMessageLoop() == MessageLoop::current());
+}
+
+GMPErr
+GMPTimerChild::SetTimer(GMPTask* aTask, int64_t aTimeoutMS)
+{
+  if (!aTask) {
+    NS_WARNING("Tried to set timer with null task!");
+    return GMPGenericErr;
+  }
+
+  if (mPlugin->GMPMessageLoop() != MessageLoop::current()) {
+    NS_WARNING("Tried to set GMP timer on non-main thread.");
+    return GMPGenericErr;
+  }
+
+  if (mTimers.Count() > MAX_NUM_TIMERS) {
+    return GMPQuotaExceededErr;
+  }
+  uint32_t timerId = mTimerCount;
+  mTimers.Put(timerId, aTask);
+  mTimerCount++;
+
+  if (!SendSetTimer(timerId, aTimeoutMS)) {
+    return GMPGenericErr;
+  }
+  return GMPNoErr;
+}
+
+bool
+GMPTimerChild::RecvTimerExpired(const uint32_t& aTimerId)
+{
+  MOZ_ASSERT(mPlugin->GMPMessageLoop() == MessageLoop::current());
+
+  GMPTask* task = mTimers.Get(aTimerId);
+  mTimers.Remove(aTimerId);
+  if (task) {
+    RunOnMainThread(task);
+  }
+  return true;
+}
+
+} // namespace gmp
+} // namespace mozilla
diff --git a/content/media/gmp/GMPTimerChild.h b/content/media/gmp/GMPTimerChild.h
new file mode 100644
index 000000000000..eb153dbd9f70
--- /dev/null
+++ b/content/media/gmp/GMPTimerChild.h
@@ -0,0 +1,46 @@
+/* -*- 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 GMPTimerChild_h_
+#define GMPTimerChild_h_
+
+#include "mozilla/gmp/PGMPTimerChild.h"
+#include "mozilla/Monitor.h"
+#include "nsDataHashtable.h"
+#include "nsHashKeys.h"
+#include "gmp-errors.h"
+#include "gmp-platform.h"
+
+namespace mozilla {
+namespace gmp {
+
+class GMPChild;
+
+class GMPTimerChild : public PGMPTimerChild
+{
+public:
+  NS_INLINE_DECL_REFCOUNTING(GMPTimerChild)
+
+  GMPTimerChild(GMPChild* aPlugin);
+
+  GMPErr SetTimer(GMPTask* aTask, int64_t aTimeoutMS);
+
+protected:
+  // GMPTimerChild
+  virtual bool RecvTimerExpired(const uint32_t& aTimerId) MOZ_OVERRIDE;
+
+private:
+  ~GMPTimerChild();
+
+  nsDataHashtable<nsUint32HashKey, GMPTask*> mTimers;
+  uint32_t mTimerCount;
+
+  GMPChild* mPlugin;
+};
+
+} // namespace gmp
+} // namespace mozilla
+
+#endif // GMPTimerChild_h_
diff --git a/content/media/gmp/GMPTimerParent.cpp b/content/media/gmp/GMPTimerParent.cpp
new file mode 100644
index 000000000000..23307bfc892a
--- /dev/null
+++ b/content/media/gmp/GMPTimerParent.cpp
@@ -0,0 +1,88 @@
+/* -*- 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/. */
+
+#include "GMPTimerParent.h"
+#include "nsComponentManagerUtils.h"
+#include "mozilla/unused.h"
+
+namespace mozilla {
+namespace gmp {
+
+GMPTimerParent::GMPTimerParent(nsIThread* aGMPThread)
+  : mGMPThread(aGMPThread)
+{
+}
+
+bool
+GMPTimerParent::RecvSetTimer(const uint32_t& aTimerId,
+                             const uint32_t& aTimeoutMs)
+{
+  MOZ_ASSERT(mGMPThread == NS_GetCurrentThread());
+
+  nsresult rv;
+  nsAutoPtr<Context> ctx(new Context());
+  ctx->mTimer = do_CreateInstance("@mozilla.org/timer;1", &rv);
+  NS_ENSURE_SUCCESS(rv, true);
+
+  ctx->mId = aTimerId;
+  rv = ctx->mTimer->SetTarget(mGMPThread);
+  NS_ENSURE_SUCCESS(rv, true);
+  ctx->mParent = this;
+
+  rv = ctx->mTimer->InitWithFuncCallback(&GMPTimerParent::GMPTimerExpired,
+                                          ctx,
+                                          aTimeoutMs,
+                                          nsITimer::TYPE_ONE_SHOT);
+  NS_ENSURE_SUCCESS(rv, true);
+
+  mTimers.PutEntry(ctx.forget());
+
+  return true;
+}
+
+/*static */
+PLDHashOperator
+GMPTimerParent::CancelTimers(nsPtrHashKey<Context>* aContext, void* aClosure)
+{
+  auto context = aContext->GetKey();
+  context->mTimer->Cancel();
+  delete context;
+  return PL_DHASH_NEXT;
+}
+
+void
+GMPTimerParent::ActorDestroy(ActorDestroyReason aWhy)
+{
+  MOZ_ASSERT(mGMPThread == NS_GetCurrentThread());
+  mTimers.EnumerateEntries(GMPTimerParent::CancelTimers, nullptr);
+  mTimers.Clear();
+}
+
+/* static */
+void
+GMPTimerParent::GMPTimerExpired(nsITimer *aTimer, void *aClosure)
+{
+  MOZ_ASSERT(aClosure);
+  nsAutoPtr<Context> ctx = static_cast<Context*>(aClosure);
+  MOZ_ASSERT(ctx->mParent);
+  if (ctx->mParent) {
+    ctx->mParent->TimerExpired(ctx);
+  }
+}
+
+void
+GMPTimerParent::TimerExpired(Context* aContext)
+{
+  MOZ_ASSERT(mGMPThread == NS_GetCurrentThread());
+
+  uint32_t id = aContext->mId;
+  mTimers.RemoveEntry(aContext);
+  if (id) {
+    unused << SendTimerExpired(id);
+  }
+}
+
+} // namespace gmp
+} // namespace mozilla
diff --git a/content/media/gmp/GMPTimerParent.h b/content/media/gmp/GMPTimerParent.h
new file mode 100644
index 000000000000..06385a6d1d24
--- /dev/null
+++ b/content/media/gmp/GMPTimerParent.h
@@ -0,0 +1,61 @@
+/* -*- 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 GMPTimerParent_h_
+#define GMPTimerParent_h_
+
+#include "mozilla/gmp/PGMPTimerParent.h"
+#include "nsITimer.h"
+#include "nsCOMPtr.h"
+#include "nsClassHashtable.h"
+#include "nsHashKeys.h"
+#include "nsAutoPtr.h"
+#include "mozilla/Monitor.h"
+#include "nsIThread.h"
+
+namespace mozilla {
+namespace gmp {
+
+class GMPTimerParent : public PGMPTimerParent {
+public:
+  NS_INLINE_DECL_REFCOUNTING(GMPTimerParent)
+  GMPTimerParent(nsIThread* aGMPThread);
+
+protected:
+  virtual bool RecvSetTimer(const uint32_t& aTimerId,
+                            const uint32_t& aTimeoutMs) MOZ_OVERRIDE;
+  virtual void ActorDestroy(ActorDestroyReason aWhy) MOZ_OVERRIDE;
+
+private:
+  ~GMPTimerParent() {}
+
+  static void GMPTimerExpired(nsITimer *aTimer, void *aClosure);
+
+  struct Context {
+    Context() {
+      MOZ_COUNT_CTOR(Context);
+    }
+    ~Context() {
+      MOZ_COUNT_DTOR(Context);
+    }
+    nsCOMPtr<nsITimer> mTimer;
+    nsRefPtr<GMPTimerParent> mParent; // Note: live timers keep the GMPTimerParent alive.
+    uint32_t mId;
+  };
+
+  static PLDHashOperator
+  CancelTimers(nsPtrHashKey<Context>* aContext, void* aClosure);
+
+  void TimerExpired(Context* aContext);
+
+  nsTHashtable<nsPtrHashKey<Context>> mTimers;
+
+  nsCOMPtr<nsIThread> mGMPThread;
+};
+
+} // namespace gmp
+} // namespace mozilla
+
+#endif // GMPTimerParent_h_
diff --git a/content/media/gmp/PGMP.ipdl b/content/media/gmp/PGMP.ipdl
index 80bebacdeb64..86dfe0bf2ca9 100644
--- a/content/media/gmp/PGMP.ipdl
+++ b/content/media/gmp/PGMP.ipdl
@@ -8,6 +8,7 @@ include protocol PGMPVideoEncoder;
 include protocol PCrashReporter;
 include protocol PGMPDecryptor;
 include protocol PGMPAudioDecoder;
+include protocol PGMPTimer;
 
 using mozilla::dom::NativeThreadId from "mozilla/dom/TabMessageUtils.h";
 
@@ -21,9 +22,11 @@ intr protocol PGMP
   manages PGMPVideoDecoder;
   manages PGMPVideoEncoder;
   manages PCrashReporter;
+  manages PGMPTimer;
 
 parent:
   async PCrashReporter(NativeThreadId tid);
+  async PGMPTimer();
 
 child:
   async PGMPAudioDecoder();
diff --git a/content/media/gmp/PGMPTimer.ipdl b/content/media/gmp/PGMPTimer.ipdl
new file mode 100644
index 000000000000..fdcf694c0c75
--- /dev/null
+++ b/content/media/gmp/PGMPTimer.ipdl
@@ -0,0 +1,22 @@
+/* -*- 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/. */
+
+include protocol PGMP;
+
+namespace mozilla {
+namespace gmp {
+
+async protocol PGMPTimer
+{
+  manager PGMP;
+child:
+  TimerExpired(uint32_t aTimerId);
+parent:
+  SetTimer(uint32_t aTimerId, uint32_t aTimeoutMs);
+  __delete__();
+};
+
+} // namespace gmp
+} // namespace mozilla
diff --git a/content/media/gmp/gmp-api/gmp-platform.h b/content/media/gmp/gmp-api/gmp-platform.h
index d35cf888fd6b..feffe0133daf 100644
--- a/content/media/gmp/gmp-api/gmp-platform.h
+++ b/content/media/gmp/gmp-api/gmp-platform.h
@@ -73,6 +73,8 @@ typedef GMPErr (*GMPCreateRecordPtr)(const char* aRecordName,
                                      uint32_t aRecordNameSize,
                                      GMPRecord** aOutRecord,
                                      GMPRecordClient* aClient);
+
+// Call on main thread only.
 typedef GMPErr (*GMPSetTimerOnMainThreadPtr)(GMPTask* aTask, int64_t aTimeoutMS);
 typedef GMPErr (*GMPGetCurrentTimePtr)(GMPTimestamp* aOutTime);
 
diff --git a/content/media/gmp/moz.build b/content/media/gmp/moz.build
index c93fc8d6f45e..2bf2083d1ee6 100644
--- a/content/media/gmp/moz.build
+++ b/content/media/gmp/moz.build
@@ -46,6 +46,8 @@ EXPORTS += [
     'GMPProcessParent.h',
     'GMPService.h',
     'GMPSharedMemManager.h',
+    'GMPTimerChild.h',
+    'GMPTimerParent.h',
     'GMPVideoDecoderChild.h',
     'GMPVideoDecoderParent.h',
     'GMPVideoDecoderProxy.h',
@@ -72,6 +74,8 @@ UNIFIED_SOURCES += [
     'GMPProcessParent.cpp',
     'GMPService.cpp',
     'GMPSharedMemManager.cpp',
+    'GMPTimerChild.cpp',
+    'GMPTimerParent.cpp',
     'GMPVideoDecoderChild.cpp',
     'GMPVideoDecoderParent.cpp',
     'GMPVideoEncodedFrameImpl.cpp',
@@ -87,6 +91,7 @@ IPDL_SOURCES += [
   'PGMP.ipdl',
   'PGMPAudioDecoder.ipdl',
   'PGMPDecryptor.ipdl',
+  'PGMPTimer.ipdl',
   'PGMPVideoDecoder.ipdl',
   'PGMPVideoEncoder.ipdl',
 ]