Bug 792652 - Simplify IPDL type hierarchy (r=dvander)

Currently all our protocols inherit from IProtocolManager<IProtocol>. I have
no idea why. This patch switches everything over to IProtocol, without any
templates. I had to move ReadActor to the .cpp file to avoid redefinition
errors.

dom/media/ipc/VideoDecoderManagerParent.h

@@ -33,7 +33,7 @@ protected:
   bool RecvReadback(const SurfaceDescriptorGPUVideo& aSD, SurfaceDescriptor* aResult) override;
   bool RecvDeallocateSurfaceDescriptorGPUVideo(const SurfaceDescriptorGPUVideo& aSD) override;
 
-  void ActorDestroy(mozilla::ipc::IProtocolManager<mozilla::ipc::IProtocol>::ActorDestroyReason) override {}
+  void ActorDestroy(mozilla::ipc::IProtocol::ActorDestroyReason) override {}
 
   void DeallocPVideoDecoderManagerParent() override;
 

dom/media/systemservices/MediaParent.h

@@ -22,7 +22,7 @@ class OriginKeyStore;
 
 class NonE10s
 {
-  typedef mozilla::ipc::IProtocolManager<mozilla::ipc::IProtocol>::ActorDestroyReason
+  typedef mozilla::ipc::IProtocol::ActorDestroyReason
       ActorDestroyReason;
 public:
   virtual ~NonE10s() {}
@@ -45,7 +45,7 @@ protected:
 template<class Super>
 class Parent : public Super
 {
-  typedef mozilla::ipc::IProtocolManager<mozilla::ipc::IProtocol>::ActorDestroyReason
+  typedef mozilla::ipc::IProtocol::ActorDestroyReason
       ActorDestroyReason;
 public:
   NS_INLINE_DECL_THREADSAFE_REFCOUNTING(Parent<Super>)

gfx/layers/IPDLActor.h

@@ -38,7 +38,7 @@ public:
     return true;
   }
 
-  typedef ipc::IProtocolManager<ipc::IProtocol>::ActorDestroyReason Why;
+  typedef ipc::IProtocol::ActorDestroyReason Why;
 
   virtual void ActorDestroy(Why) override {
     DestroyIfNeeded();

ipc/glue/ProtocolUtils.cpp

@@ -365,5 +365,38 @@ TableToArray(const nsTHashtable<nsPtrHashKey<void>>& aTable,
   }
 }
 
+Maybe<IProtocol*>
+IProtocol::ReadActor(const IPC::Message* aMessage, PickleIterator* aIter, bool aNullable,
+                     const char* aActorDescription, int32_t aProtocolTypeId)
+{
+    int32_t id;
+    if (!IPC::ReadParam(aMessage, aIter, &id)) {
+        ActorIdReadError(aActorDescription);
+        return Nothing();
+    }
+
+    if (id == 1 || (id == 0 && !aNullable)) {
+        BadActorIdError(aActorDescription);
+        return Nothing();
+    }
+
+    if (id == 0) {
+        return Some(static_cast<IProtocol*>(nullptr));
+    }
+
+    IProtocol* listener = this->Lookup(id);
+    if (!listener) {
+        ActorLookupError(aActorDescription);
+        return Nothing();
+    }
+
+    if (listener->GetProtocolTypeId() != aProtocolTypeId) {
+        MismatchedActorTypeError(aActorDescription);
+        return Nothing();
+    }
+
+    return Some(listener);
+}
+
 } // namespace ipc
 } // namespace mozilla

ipc/glue/ProtocolUtils.h

@@ -130,8 +130,7 @@ struct Trigger
     uint32_t mMessage : 31;
 };
 
-template<class ListenerT>
-class IProtocolManager
+class IProtocol : public MessageListener
 {
 public:
     enum ActorDestroyReason {
@@ -144,11 +143,11 @@ public:
 
     typedef base::ProcessId ProcessId;
 
-    virtual int32_t Register(ListenerT*) = 0;
-    virtual int32_t RegisterID(ListenerT*, int32_t) = 0;
-    virtual ListenerT* Lookup(int32_t) = 0;
+    virtual int32_t Register(IProtocol*) = 0;
+    virtual int32_t RegisterID(IProtocol*, int32_t) = 0;
+    virtual IProtocol* Lookup(int32_t) = 0;
     virtual void Unregister(int32_t) = 0;
-    virtual void RemoveManagee(int32_t, ListenerT*) = 0;
+    virtual void RemoveManagee(int32_t, IProtocol*) = 0;
 
     virtual Shmem::SharedMemory* CreateSharedMemory(
         size_t, SharedMemory::SharedMemoryType, bool, int32_t*) = 0;
@@ -162,19 +161,12 @@ public:
 
     virtual void FatalError(const char* const aProtocolName, const char* const aErrorMsg) const = 0;
 
-    Maybe<ListenerT*> ReadActor(const IPC::Message* aMessage, PickleIterator* aIter, bool aNullable,
+    Maybe<IProtocol*> ReadActor(const IPC::Message* aMessage, PickleIterator* aIter, bool aNullable,
                                 const char* aActorDescription, int32_t aProtocolTypeId);
 };
 
 typedef IPCMessageStart ProtocolId;
 
-/**
- * All RPC protocols should implement this interface.
- */
-class IProtocol : public MessageListener
-{
-};
-
 template<class PFooSide>
 class Endpoint;
 
@@ -319,40 +311,6 @@ UnpackChannelOpened(const PrivateIPDLInterface&,
                     const IPC::Message&,
                     TransportDescriptor*, base::ProcessId*, ProtocolId*);
 
-template<typename ListenerT>
-Maybe<ListenerT*>
-IProtocolManager<ListenerT>::ReadActor(const IPC::Message* aMessage, PickleIterator* aIter, bool aNullable,
-                                       const char* aActorDescription, int32_t aProtocolTypeId)
-{
-    int32_t id;
-    if (!IPC::ReadParam(aMessage, aIter, &id)) {
-        ActorIdReadError(aActorDescription);
-        return Nothing();
-    }
-
-    if (id == 1 || (id == 0 && !aNullable)) {
-        BadActorIdError(aActorDescription);
-        return Nothing();
-    }
-
-    if (id == 0) {
-        return Some(static_cast<ListenerT*>(nullptr));
-    }
-
-    ListenerT* listener = this->Lookup(id);
-    if (!listener) {
-        ActorLookupError(aActorDescription);
-        return Nothing();
-    }
-
-    if (static_cast<MessageListener*>(listener)->GetProtocolTypeId() != aProtocolTypeId) {
-        MismatchedActorTypeError(aActorDescription);
-        return Nothing();
-    }
-
-    return Some(listener);
-}
-
 #if defined(XP_WIN)
 // This is a restricted version of Windows' DuplicateHandle() function
 // that works inside the sandbox and can send handles but not retrieve

ipc/ipdl/ipdl/lower.py

@@ -1093,13 +1093,8 @@ class Protocol(ipdl.ast.Protocol):
     def fqListenerName(self):
       return 'mozilla::ipc::MessageListener'
 
-    def fqBaseClass(self):
-        return 'mozilla::ipc::IProtocol'
-
     def managerInterfaceType(self, ptr=0):
-        return Type('mozilla::ipc::IProtocolManager',
-                    ptr=ptr,
-                    T=Type(self.fqBaseClass()))
+        return Type('mozilla::ipc::IProtocol', ptr=ptr)
 
     def openedProtocolInterfaceType(self, ptr=0):
         return Type('mozilla::ipc::IToplevelProtocol',
@@ -2625,7 +2620,7 @@ class _GenerateProtocolActorCode(ipdl.ast.Visitor):
 
     def standardTypedefs(self):
         return [
-            Typedef(Type(self.protocol.fqBaseClass()), 'ProtocolBase'),
+            Typedef(Type('mozilla::ipc::IProtocol'), 'ProtocolBase'),
             Typedef(Type('IPC::Message'), 'Message'),
             Typedef(Type(self.protocol.channelName()), 'Channel'),
             Typedef(Type(self.protocol.fqListenerName()), 'ChannelListener'),
@@ -2826,8 +2821,7 @@ class _GenerateProtocolActorCode(ipdl.ast.Visitor):
 
         self.cls = Class(
             self.clsname,
-            inherits=[ Inherit(Type(p.fqBaseClass()), viz='public'),
-                       Inherit(p.managerInterfaceType(), viz='protected') ] +
+            inherits=[ Inherit(p.managerInterfaceType(), viz='public') ] +
             optinherits,
             abstract=True)
 

js/ipc/WrapperOwner.h

@@ -20,8 +20,7 @@ namespace jsipc {
 class WrapperOwner : public virtual JavaScriptShared
 {
   public:
-    typedef mozilla::ipc::IProtocolManager<
-                       mozilla::ipc::IProtocol>::ActorDestroyReason
+    typedef mozilla::ipc::IProtocol::ActorDestroyReason
            ActorDestroyReason;
 
     WrapperOwner();