Bug 1779792 - Part 3: Use an endpoint to bind the initial actor in parent processes, r=ipc-reviewers,necko-reviewers,media-playback-reviewers,alwu,mccr8

This improves consistency with the child process case, and will make it easier
to attach additional state without needing to thread it through every child
process callsite manually.

Differential Revision: https://phabricator.services.mozilla.com/D153619

dom/ipc/ContentParent.cpp

@@ -2681,9 +2681,7 @@ bool ContentParent::LaunchSubprocessResolve(bool aIsSync,
     sCreatedFirstContentProcess = true;
   }
 
-  base::ProcessId procId =
-      base::GetProcId(mSubprocess->GetChildProcessHandle());
-  Open(mSubprocess->TakeInitialPort(), procId);
+  mSubprocess->TakeInitialEndpoint().Bind(this);
 
   ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
   if (!cpm) {

dom/media/gmp/GMPParent.cpp

@@ -326,8 +326,7 @@ nsresult GMPParent::LoadProcess() {
     mChildPid = base::GetProcId(mProcess->GetChildProcessHandle());
     GMP_PARENT_LOG_DEBUG("%s: Launched new child process", __FUNCTION__);
 
-    bool opened = Open(mProcess->TakeInitialPort(),
-                       base::GetProcId(mProcess->GetChildProcessHandle()));
+    bool opened = mProcess->TakeInitialEndpoint().Bind(this);
     if (!opened) {
       GMP_PARENT_LOG_DEBUG("%s: Failed to open channel to new child process",
                            __FUNCTION__);

dom/media/ipc/RDDProcessHost.cpp

@@ -169,8 +169,7 @@ void RDDProcessHost::InitAfterConnect(bool aSucceeded) {
   }
   mProcessToken = ++sRDDProcessTokenCounter;
   mRDDChild = MakeUnique<RDDChild>(this);
-  DebugOnly<bool> rv = mRDDChild->Open(
-      TakeInitialPort(), base::GetProcId(GetChildProcessHandle()));
+  DebugOnly<bool> rv = TakeInitialEndpoint().Bind(mRDDChild.get());
   MOZ_ASSERT(rv);
 
   // Only clear mPrefSerializer in the success case to avoid a

gfx/ipc/GPUProcessHost.cpp

@@ -144,8 +144,7 @@ void GPUProcessHost::InitAfterConnect(bool aSucceeded) {
   if (aSucceeded) {
     mProcessToken = ++sProcessTokenCounter;
     mGPUChild = MakeUnique<GPUChild>(this);
-    DebugOnly<bool> rv = mGPUChild->Open(
-        TakeInitialPort(), base::GetProcId(GetChildProcessHandle()));
+    DebugOnly<bool> rv = TakeInitialEndpoint().Bind(mGPUChild.get());
     MOZ_ASSERT(rv);
 
     mGPUChild->Init();

gfx/vr/ipc/VRProcessParent.cpp

@@ -163,8 +163,7 @@ bool VRProcessParent::InitAfterConnect(bool aSucceeded) {
 
     mVRChild = MakeUnique<VRChild>(this);
 
-    DebugOnly<bool> rv = mVRChild->Open(
-        TakeInitialPort(), base::GetProcId(GetChildProcessHandle()));
+    DebugOnly<bool> rv = TakeInitialEndpoint().Bind(mVRChild.get());
     MOZ_ASSERT(rv);
 
     mVRChild->Init();

ipc/docs/processes.rst

@@ -560,7 +560,8 @@ behavior is fairly clear:
               return;
             }
 
-            new DemoParent(std::move(host));
+            auto actor = MakeRefPtr<DemoParent>(std::move(host));
+            actor->Init();
           });
     }
 
@@ -579,20 +580,21 @@ the new host, if successful.
 
 In this sample, the ``DemoParent`` is owned (in the reference-counting sense)
 by IPDL, which is why it doesn't get assigned to anything.  This simplifies the
-design dramatically.  IPDL takes ownership when the actor calls ``Open`` in its
-constructor:
+design dramatically.  IPDL takes ownership when the actor calls ``Bind`` from
+the ``Init`` method:
 
 .. code-block:: c++
 
     DemoParent::DemoParent(UniqueHost&& aHost)
-        : mHost(std::move(aHost)) {
-      Open(mHost->TakeInitialPort(),
-           base::GetProcId(mHost->GetChildProcessHandle()));
+        : mHost(std::move(aHost)) {}
+
+    DemoParent::Init() {
+      mHost->TakeInitialEndpoint().Bind(this);
       // ...
       mHost->MakeBridgeAndResolve();
     }
 
-After the ``Open`` call, the actor is live and communication with the new
+After the ``Bind`` call, the actor is live and communication with the new
 process can begin.  The constructor concludes by initiating the process of
 connecting the ``PDemoHelpline`` actors; ``Host::MakeBridgeAndResolve`` will be
 covered in `Creating a New Top Level Actor`_.  However, before we get into

ipc/glue/GeckoChildProcessHost.h

@@ -14,6 +14,7 @@
 #include "chrome/common/ipc_message.h"
 #include "mojo/core/ports/port_ref.h"
 
+#include "mozilla/ipc/Endpoint.h"
 #include "mozilla/ipc/FileDescriptor.h"
 #include "mozilla/ipc/NodeChannel.h"
 #include "mozilla/ipc/ScopedPort.h"
@@ -127,7 +128,11 @@ class GeckoChildProcessHost : public ChildProcessHost,
   IPC::Channel* GetChannel() { return channelp(); }
   ChannelId GetChannelId() { return channel_id(); }
 
-  ScopedPort TakeInitialPort() { return std::move(mInitialPort); }
+  UntypedEndpoint TakeInitialEndpoint() {
+    return UntypedEndpoint{PrivateIPDLInterface{}, std::move(mInitialPort),
+                           base::GetCurrentProcId(),
+                           base::GetProcId(mChildProcessHandle)};
+  }
 
   // Returns a "borrowed" handle to the child process - the handle returned
   // by this function must not be closed by the caller.

ipc/glue/UtilityProcessHost.cpp

@@ -182,8 +182,7 @@ void UtilityProcessHost::InitAfterConnect(bool aSucceeded) {
   }
 
   mUtilityProcessParent = MakeRefPtr<UtilityProcessParent>(this);
-  DebugOnly<bool> rv = mUtilityProcessParent->Open(
-      TakeInitialPort(), base::GetProcId(GetChildProcessHandle()));
+  DebugOnly<bool> rv = TakeInitialEndpoint().Bind(mUtilityProcessParent.get());
   MOZ_ASSERT(rv);
 
   // Only clear mPrefSerializer in the success case to avoid a

ipc/ipdl/test/gtest/IPDLUnitTest.cpp

@@ -61,9 +61,7 @@ already_AddRefed<IPDLUnitTestParent> IPDLUnitTestParent::CreateCrossProcess() {
     return nullptr;
   }
 
-  if (!parent->Open(
-          parent->mSubprocess->TakeInitialPort(),
-          base::GetProcId(parent->mSubprocess->GetChildProcessHandle()))) {
+  if (!parent->mSubprocess->TakeInitialEndpoint().Bind(parent.get())) {
     ADD_FAILURE() << "Opening the parent actor failed";
     return nullptr;
   }

netwerk/ipc/SocketProcessHost.cpp

@@ -166,8 +166,7 @@ void SocketProcessHost::InitAfterConnect(bool aSucceeded) {
   }
 
   mSocketProcessParent = MakeUnique<SocketProcessParent>(this);
-  DebugOnly<bool> rv = mSocketProcessParent->Open(
-      TakeInitialPort(), base::GetProcId(GetChildProcessHandle()));
+  DebugOnly<bool> rv = TakeInitialEndpoint().Bind(mSocketProcessParent.get());
   MOZ_ASSERT(rv);
 
   SocketPorcessInitAttributes attributes;

security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerParent.cpp

@@ -27,7 +27,7 @@ RefPtr<GenericPromise> RemoteSandboxBrokerParent::Launch(
   // Note: we rely on the caller to keep this instance alive while we launch
   // the process, so that these closures point to valid memory.
   auto resolve = [this](base::ProcessHandle handle) {
-    mOpened = Open(mProcess->TakeInitialPort(), base::GetProcId(handle));
+    mOpened = mProcess->TakeInitialEndpoint().Bind(this);
     if (!mOpened) {
       mProcess->Destroy();
       mProcess = nullptr;