Refactor structured clone JSAPI to prevent mismatched scopes.

Roll-up of bugs 1442722, 1455071, 1433642, 1456604 and 1458320.

2 files changed, 14 insertions, 13 deletions

diff --git a/dom/ipc/StructuredCloneData.cpp b/dom/ipc/StructuredCloneData.cpp
index 98f56904f..2c1fff2ac 100644
--- a/dom/ipc/StructuredCloneData.cpp
+++ b/dom/ipc/StructuredCloneData.cpp
@@ -88,7 +88,7 @@ StructuredCloneData::Write(JSContext* aCx,
     return;
   }
 
-  JSStructuredCloneData data;
+  JSStructuredCloneData data(mBuffer->scope());
   mBuffer->abandon();
   mBuffer->steal(&data);
   mBuffer = nullptr;
@@ -107,7 +107,7 @@ StructuredCloneData::ReadIPCParams(const IPC::Message* aMsg,
                                    PickleIterator* aIter)
 {
   MOZ_ASSERT(!mInitialized);
-  JSStructuredCloneData data;
+  JSStructuredCloneData data(JS::StructuredCloneScope::DifferentProcess);
   if (!ReadParam(aMsg, aIter, &data)) {
     return false;
   }
diff --git a/dom/ipc/StructuredCloneData.h b/dom/ipc/StructuredCloneData.h
index 9e427e938..64cfd1935 100644
--- a/dom/ipc/StructuredCloneData.h
+++ b/dom/ipc/StructuredCloneData.h
@@ -31,8 +31,8 @@ public:
   static already_AddRefed<SharedJSAllocatedData>
   CreateFromExternalData(const char* aData, size_t aDataLength)
   {
-    JSStructuredCloneData buf;
-    buf.WriteBytes(aData, aDataLength);
+    JSStructuredCloneData buf(JS::StructuredCloneScope::DifferentProcess);
+    buf.AppendBytes(aData, aDataLength);
     RefPtr<SharedJSAllocatedData> sharedData =
       new SharedJSAllocatedData(Move(buf));
     return sharedData.forget();
@@ -41,12 +41,8 @@ public:
   static already_AddRefed<SharedJSAllocatedData>
   CreateFromExternalData(const JSStructuredCloneData& aData)
   {
-    JSStructuredCloneData buf;
-    auto iter = aData.Iter();
-    while (!iter.Done()) {
-      buf.WriteBytes(iter.Data(), iter.RemainingInSegment());
-      iter.Advance(aData, iter.RemainingInSegment());
-    }
+    JSStructuredCloneData buf(aData.scope());
+    buf.Append(aData);
     RefPtr<SharedJSAllocatedData> sharedData =
       new SharedJSAllocatedData(Move(buf));
     return sharedData.forget();
@@ -70,6 +66,7 @@ public:
     : StructuredCloneHolder(StructuredCloneHolder::CloningSupported,
                             StructuredCloneHolder::TransferringSupported,
                             StructuredCloneHolder::StructuredCloneScope::DifferentProcess)
+    , mExternalData(StructuredCloneHolder::StructuredCloneScope::DifferentProcess)
     , mInitialized(false)
   {}
 
@@ -113,10 +110,9 @@ public:
 
   bool UseExternalData(const JSStructuredCloneData& aData)
   {
-    auto iter = aData.Iter();
+    auto iter = aData.Start();
     bool success = false;
-    mExternalData =
-      aData.Borrow<js::SystemAllocPolicy>(iter, aData.Size(), &success);
+    mExternalData = aData.Borrow(iter, aData.Size(), &success);
     mInitialized = true;
     return success;
   }
@@ -133,6 +129,11 @@ public:
     return mSharedData ? mSharedData->Data() : mExternalData;
   }
 
+  void InitScope(JS::StructuredCloneScope aScope)
+  {
+    Data().initScope(aScope);
+  }
+
   size_t DataLength() const
   {
     return mSharedData ? mSharedData->DataLength() : mExternalData.Size();