Bug 1505895 - Add handler for changes to a recording/replaying child's state, r=lsmyth.

--HG--
extra : rebase_source : 5cf996fd6d7dfef4a9fc85d697ad35819809ad96

devtools/server/actors/replay/debugger.js

@@ -76,6 +76,8 @@ ReplayDebugger.prototype = {
     return this._sendRequest({ type: "recordingEndpoint" });
   },
 
+  replayIsRecording: RecordReplayControl.childIsRecording,
+
   addDebuggee() {},
   removeAllDebuggees() {},
 
@@ -384,6 +386,14 @@ ReplayDebugger.prototype = {
                                        handler.call(this, this.getNewestFrame()); });
   },
 
+  get replayingOnPositionChange() {
+    return this._breakpointKindGetter("PositionChange");
+  },
+  set replayingOnPositionChange(handler) {
+    this._breakpointKindSetter("PositionChange", handler,
+                               () => { handler.call(this); });
+  },
+
   getNewConsoleMessage() {
     const message = this._sendRequest({ type: "getNewConsoleMessage" });
     return this._convertConsoleMessage(message);

toolkit/recordreplay/ipc/JSControl.cpp

@@ -432,6 +432,14 @@ Middleman_HadRepaintFailure(JSContext* aCx, unsigned aArgc, Value* aVp)
   return true;
 }
 
+static bool
+Middleman_ChildIsRecording(JSContext* aCx, unsigned aArgc, Value* aVp)
+{
+  CallArgs args = CallArgsFromVp(aArgc, aVp);
+  args.rval().setBoolean(parent::ActiveChildIsRecording());
+  return true;
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 // Devtools Sandbox
 ///////////////////////////////////////////////////////////////////////////////
@@ -931,6 +939,7 @@ static const JSFunctionSpec gMiddlemanMethods[] = {
   JS_FN("maybeSwitchToReplayingChild", Middleman_MaybeSwitchToReplayingChild, 0, 0),
   JS_FN("hadRepaint", Middleman_HadRepaint, 2, 0),
   JS_FN("hadRepaintFailure", Middleman_HadRepaintFailure, 0, 0),
+  JS_FN("childIsRecording", Middleman_ChildIsRecording, 0, 0),
   JS_FS_END
 };
 

toolkit/recordreplay/ipc/JSControl.h

@@ -66,7 +66,11 @@ struct BreakpointPosition
     // Break when the debugger should pause even if no breakpoint has been
     // set: the beginning or end of the replay has been reached, or a time
     // warp has reached its destination.
-    ForcedPause
+    ForcedPause,
+
+    // Break when the child process reaches a checkpoint or we switch between
+    // recording and replaying child processes.
+    PositionChange
   ));
 
   Kind mKind;
@@ -120,6 +124,7 @@ struct BreakpointPosition
     case ConsoleMessage: return "ConsoleMessage";
     case WarpTarget: return "WarpTarget";
     case ForcedPause: return "ForcedPause";
+    case PositionChange: return "PositionChange";
     }
     MOZ_CRASH("Bad BreakpointPosition kind");
   }

toolkit/recordreplay/ipc/ParentIPC.cpp

@@ -14,6 +14,7 @@
 #include "js/Proxy.h"
 #include "mozilla/dom/ContentProcessMessageManager.h"
 #include "InfallibleVector.h"
+#include "JSControl.h"
 #include "Monitor.h"
 #include "ProcessRecordReplay.h"
 #include "ProcessRedirect.h"
@@ -583,6 +584,10 @@ SpawnReplayingChildren()
   AssignMajorCheckpoint(gSecondReplayingChild, CheckpointId::First);
 }
 
+// Hit any installed breakpoints with the specified kind.
+static void HitBreakpointsWithKind(js::BreakpointPosition::Kind aKind,
+                                   bool aRecordingBoundary = false);
+
 // Change the current active child, and select a new role for the old one.
 static void
 SwitchActiveChild(ChildProcessInfo* aChild, bool aRecoverPosition = true)
@@ -608,6 +613,12 @@ SwitchActiveChild(ChildProcessInfo* aChild, bool aRecoverPosition = true)
     oldActiveChild->RecoverToCheckpoint(oldActiveChild->MostRecentSavedCheckpoint());
     oldActiveChild->SetRole(MakeUnique<ChildRoleStandby>());
   }
+
+  // Position state is affected when we switch between recording and
+  // replaying children.
+  if (aChild->IsRecording() != oldActiveChild->IsRecording()) {
+    HitBreakpointsWithKind(js::BreakpointPosition::Kind::PositionChange);
+  }
 }
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -995,9 +1006,6 @@ static bool gChildExecuteBackward = false;
 // main thread. This will continue execution in the preferred direction.
 static bool gResumeForwardOrBackward = false;
 
-// Hit any breakpoints installed for forced pauses.
-static void HitForcedPauseBreakpoints(bool aRecordingBoundary);
-
 static void
 MaybeSendRepaintMessage()
 {
@@ -1050,7 +1058,8 @@ Resume(bool aForward)
     // Don't rewind if we are at the beginning of the recording.
     if (targetCheckpoint == CheckpointId::Invalid) {
       SendMessageToUIProcess("HitRecordingBeginning");
-      HitForcedPauseBreakpoints(true);
+      HitBreakpointsWithKind(js::BreakpointPosition::Kind::ForcedPause,
+                             /* aRecordingBoundary = */ true);
       return;
     }
 
@@ -1077,7 +1086,8 @@ Resume(bool aForward)
       MOZ_RELEASE_ASSERT(!gActiveChild->IsRecording());
       if (!gRecordingChild) {
         SendMessageToUIProcess("HitRecordingEndpoint");
-        HitForcedPauseBreakpoints(true);
+        HitBreakpointsWithKind(js::BreakpointPosition::Kind::ForcedPause,
+                               /* aRecordingBoundary = */ true);
         return;
       }
 
@@ -1142,7 +1152,7 @@ TimeWarp(const js::ExecutionPoint& aTarget)
 
   gActiveChild->WaitUntilPaused();
   SendMessageToUIProcess("TimeWarpFinished");
-  HitForcedPauseBreakpoints(false);
+  HitBreakpointsWithKind(js::BreakpointPosition::Kind::ForcedPause);
 }
 
 void
@@ -1189,6 +1199,9 @@ RecvHitCheckpoint(const HitCheckpointMessage& aMsg)
   UpdateCheckpointTimes(aMsg);
   MaybeUpdateGraphicsAtCheckpoint(aMsg.mCheckpointId);
 
+  // Position state is affected when new checkpoints are reached.
+  HitBreakpointsWithKind(js::BreakpointPosition::Kind::PositionChange);
+
   // Resume either forwards or backwards. Break the resume off into a separate
   // runnable, to avoid starving any code already on the stack and waiting for
   // the process to pause. Immediately resume if the main thread is blocked.
@@ -1247,11 +1260,11 @@ RecvHitBreakpoint(const HitBreakpointMessage& aMsg)
 }
 
 static void
-HitForcedPauseBreakpoints(bool aRecordingBoundary)
+HitBreakpointsWithKind(js::BreakpointPosition::Kind aKind, bool aRecordingBoundary)
 {
   Vector<uint32_t> breakpoints;
-  gActiveChild->GetMatchingInstalledBreakpoints([=](js::BreakpointPosition::Kind aKind) {
+  gActiveChild->GetMatchingInstalledBreakpoints([=](js::BreakpointPosition::Kind aInstalled) {
-      return aKind == js::BreakpointPosition::ForcedPause;
+      return aInstalled == aKind;
     }, breakpoints);
   if (!breakpoints.empty()) {
     uint32_t* newBreakpoints = new uint32_t[breakpoints.length()];