Bug 1850865: Add helpers for stringifying protocol sides. r=ipc-reviewers,nika

Depends on D187167

Differential Revision: https://phabricator.services.mozilla.com/D187213

dom/ipc/jsactor/JSActorManager.cpp

@@ -54,8 +54,9 @@ already_AddRefed<JSActor> JSActorManager::GetActor(JSContext* aCx,
     return nullptr;
   }
 
-  bool isParent = nativeActor->GetSide() == mozilla::ipc::ParentSide;
-  auto& side = isParent ? protocol->Parent() : protocol->Child();
+  auto& side = nativeActor->GetSide() == mozilla::ipc::ParentSide
+                   ? protocol->Parent()
+                   : protocol->Child();
 
   // We're about to construct the actor, so make sure we're in the JSM realm
   // while importing etc.
@@ -86,7 +87,7 @@ already_AddRefed<JSActor> JSActorManager::GetActor(JSContext* aCx,
     // Load the specific property from our module.
     JS::Rooted<JS::Value> ctor(aCx);
     nsAutoCString ctorName(aName);
-    ctorName.Append(isParent ? "Parent"_ns : "Child"_ns);
+    ctorName.Append(StringFromIPCSide(nativeActor->GetSide()));
     if (!JS_GetProperty(aCx, exports, ctorName.get(), &ctor)) {
       aRv.NoteJSContextException(aCx);
       return nullptr;

ipc/glue/MessageChannel.cpp

@@ -561,17 +561,6 @@ int MessageChannel::DispatchingSyncMessageNestedLevel() const {
              : 0;
 }
 
-static const char* StringFromIPCSide(Side side) {
-  switch (side) {
-    case ChildSide:
-      return "Child";
-    case ParentSide:
-      return "Parent";
-    default:
-      return "Unknown";
-  }
-}
-
 static void PrintErrorMessage(Side side, const char* channelName,
                               const char* msg) {
   printf_stderr("\n###!!! [%s][%s] Error: %s\n\n", StringFromIPCSide(side),
@@ -947,8 +936,7 @@ bool MessageChannel::MaybeInterceptSpecialIOMessage(const Message& aMsg) {
             "channel.\n",
             XRE_GeckoProcessTypeToString(XRE_GetProcessType()),
             static_cast<uint32_t>(base::GetCurrentProcId()),
-            mListener->GetProtocolName(),
-            (mSide == ChildSide) ? "Child" : "Parent");
+            mListener->GetProtocolName(), StringFromIPCSide(mSide));
       }
 
       // Notify the worker thread that the connection has been closed, as we
@@ -2217,8 +2205,7 @@ void MessageChannel::DebugAbort(const char* file, int line, const char* cond,
   printf_stderr(
       "###!!! [MessageChannel][%s][%s:%d] "
       "Assertion (%s) failed.  %s %s\n",
-      mSide == ChildSide ? "Child" : "Parent", file, line, cond, why,
-      reply ? "(reply)" : "");
+      StringFromIPCSide(mSide), file, line, cond, why, reply ? "(reply)" : "");
 
   MessageQueue pending = std::move(mPending);
   while (!pending.isEmpty()) {

ipc/glue/MessageLink.cpp

@@ -28,6 +28,17 @@ using namespace mozilla;
 namespace mozilla {
 namespace ipc {
 
+const char* StringFromIPCSide(Side side) {
+  switch (side) {
+    case ChildSide:
+      return "Child";
+    case ParentSide:
+      return "Parent";
+    default:
+      return "Unknown";
+  }
+}
+
 MessageLink::MessageLink(MessageChannel* aChan) : mChan(aChan) {}
 
 MessageLink::~MessageLink() {

ipc/glue/MessageLink.h

@@ -43,6 +43,8 @@ struct HasResultCodes {
 
 enum Side : uint8_t { ParentSide, ChildSide, UnknownSide };
 
+const char* StringFromIPCSide(Side side);
+
 class MessageLink {
  public:
   typedef IPC::Message Message;

ipc/glue/ProtocolUtils.cpp

@@ -331,8 +331,7 @@ IProtocol::~IProtocol() {
         nsPrintfCString("Actor destructor for '%s%s' called before IPC "
                         "lifecycle complete!\n"
                         "References to this actor may unexpectedly dangle!",
-                        GetProtocolName(),
-                        GetSide() == ChildSide ? "Child" : "Parent")
+                        GetProtocolName(), StringFromIPCSide(GetSide()))
             .get());
 
     mLifecycleProxy->mActor = nullptr;

ipc/ipdl/ipdl/lower.py

@@ -355,6 +355,13 @@ def _cxxLifecycleProxyType(ptr=False):
     return Type("mozilla::ipc::ActorLifecycleProxy", ptr=ptr)
 
 
+def _cxxSide(side):
+    if side == "child":
+        return ExprVar("mozilla::ipc::ChildSide")
+    if side == "parent":
+        return ExprVar("mozilla::ipc::ParentSide")
+    assert 0
+
 def _otherSide(side):
     if side == "child":
         return "parent"
@@ -1915,13 +1922,9 @@ class _ParamTraits:
 
     @classmethod
     def ifsideis(cls, rdrwtr, side, then, els=None):
-        cxxside = ExprVar("mozilla::ipc::ChildSide")
-        if side == "parent":
-            cxxside = ExprVar("mozilla::ipc::ParentSide")
-
         ifstmt = StmtIf(
             ExprBinary(
-                cxxside,
+                _cxxSide(side),
                 "==",
                 ExprCode("${rdrwtr}->GetActor()->GetSide()", rdrwtr=rdrwtr),
             )
@@ -5570,11 +5573,6 @@ class _GenerateProtocolActorCode(ipdl.ast.Visitor):
 
     def logMessage(self, md, msgptr, pfx, actor=None, receiving=False):
         actorname = _actorName(self.protocol.name, self.side)
-        if self.side == "parent":
-            side = ExprVar("mozilla::ipc::ParentSide")
-        else:
-            side = ExprVar("mozilla::ipc::ChildSide")
-
         return StmtCode(
             """
             if (mozilla::ipc::LoggingEnabledFor(${protocolname}, ${side})) {
@@ -5587,7 +5585,7 @@ class _GenerateProtocolActorCode(ipdl.ast.Visitor):
             }
             """,
             protocolname=ExprLiteral.String(self.protocol.name),
-            side=side,
+            side=_cxxSide(self.side),
             actorname=ExprLiteral.String(actorname),
             actor=actor or ExprVar.THIS,
             pfx=ExprLiteral.String(pfx),