From 3fb149d9d73289ba0d68c50d7fdf8c88394c07ae Mon Sep 17 00:00:00 2001
From: Bobby Holley <bobbyholley@gmail.com>
Date: Fri, 21 Feb 2014 15:55:31 -0800
Subject: [PATCH] Bug 975277 - Clean up the XPCWN XrayHolder a bit. r=gabor

---
 js/xpconnect/wrappers/AccessCheck.cpp    |  2 +-
 js/xpconnect/wrappers/WrapperFactory.cpp |  2 +-
 js/xpconnect/wrappers/XrayWrapper.cpp    | 31 +++++++++++++++---------
 js/xpconnect/wrappers/XrayWrapper.h      |  2 +-
 4 files changed, 22 insertions(+), 15 deletions(-)

diff --git a/js/xpconnect/wrappers/AccessCheck.cpp b/js/xpconnect/wrappers/AccessCheck.cpp
index c1e48a6e3920..5363afadc7bf 100644
--- a/js/xpconnect/wrappers/AccessCheck.cpp
+++ b/js/xpconnect/wrappers/AccessCheck.cpp
@@ -205,7 +205,7 @@ AccessCheck::isCrossOriginAccessPermitted(JSContext *cx, JSObject *wrapperArg, j
 
     const char *name;
     const js::Class *clasp = js::GetObjectClass(obj);
-    MOZ_ASSERT(Jsvalify(clasp) != &XrayUtils::HolderClass, "shouldn't have a holder here");
+    MOZ_ASSERT(!XrayUtils::IsXPCWNHolderClass(Jsvalify(clasp)), "shouldn't have a holder here");
     if (clasp->ext.innerObject)
         name = "Window";
     else
diff --git a/js/xpconnect/wrappers/WrapperFactory.cpp b/js/xpconnect/wrappers/WrapperFactory.cpp
index fba833c9ab39..ebad2e187638 100644
--- a/js/xpconnect/wrappers/WrapperFactory.cpp
+++ b/js/xpconnect/wrappers/WrapperFactory.cpp
@@ -374,7 +374,7 @@ WrapperFactory::Rewrap(JSContext *cx, HandleObject existing, HandleObject obj,
                GetProxyHandler(obj) == &XrayWaiver ||
                js::GetObjectClass(obj)->ext.innerObject,
                "wrapped object passed to rewrap");
-    MOZ_ASSERT(JS_GetClass(obj) != &XrayUtils::HolderClass, "trying to wrap a holder");
+    MOZ_ASSERT(!XrayUtils::IsXPCWNHolderClass(JS_GetClass(obj)), "trying to wrap a holder");
     MOZ_ASSERT(!js::IsInnerObject(obj));
     // We sometimes end up here after nsContentUtils has been shut down but before
     // XPConnect has been shut down, so check the context stack the roundabout way.
diff --git a/js/xpconnect/wrappers/XrayWrapper.cpp b/js/xpconnect/wrappers/XrayWrapper.cpp
index 79bfd7f5e105..9aa45ac2c0bd 100644
--- a/js/xpconnect/wrappers/XrayWrapper.cpp
+++ b/js/xpconnect/wrappers/XrayWrapper.cpp
@@ -37,18 +37,6 @@ using js::CheckedUnwrap;
 
 namespace xpc {
 
-static const uint32_t JSSLOT_RESOLVING = 0;
-
-namespace XrayUtils {
-
-const JSClass HolderClass = {
-    "NativePropertyHolder",
-    JSCLASS_HAS_RESERVED_SLOTS(2),
-    JS_PropertyStub,        JS_DeletePropertyStub, holder_get,      holder_set,
-    JS_EnumerateStub,       JS_ResolveStub,  JS_ConvertStub
-};
-}
-
 using namespace XrayUtils;
 
 XrayType
@@ -65,6 +53,7 @@ GetXrayType(JSObject *obj)
     return NotXray;
 }
 
+const uint32_t JSSLOT_RESOLVING = 0;
 ResolvingId::ResolvingId(JSContext *cx, HandleObject wrapper, HandleId id)
   : mId(id),
     mHolder(cx, getHolderObject(wrapper)),
@@ -231,9 +220,16 @@ public:
 
     virtual JSObject* createHolder(JSContext *cx, JSObject *wrapper);
 
+    static const JSClass HolderClass;
     static XPCWrappedNativeXrayTraits singleton;
 };
 
+const JSClass XPCWrappedNativeXrayTraits::HolderClass = {
+    "NativePropertyHolder", JSCLASS_HAS_RESERVED_SLOTS(2),
+    JS_PropertyStub, JS_DeletePropertyStub, holder_get, holder_set,
+    JS_EnumerateStub, JS_ResolveStub, JS_ConvertStub
+};
+
 class DOMXrayTraits : public XrayTraits
 {
 public:
@@ -535,6 +531,17 @@ XPCWrappedNativeXrayTraits::isResolving(JSContext *cx, JSObject *holder,
     return cur->isResolving(id);
 }
 
+namespace XrayUtils {
+
+bool
+IsXPCWNHolderClass(const JSClass *clasp)
+{
+  return clasp == &XPCWrappedNativeXrayTraits::HolderClass;
+}
+
+}
+
+
 // Some DOM objects have shared properties that don't have an explicit
 // getter/setter and rely on the class getter/setter. We install a
 // class getter/setter on the holder object to trigger them.
diff --git a/js/xpconnect/wrappers/XrayWrapper.h b/js/xpconnect/wrappers/XrayWrapper.h
index 9b1cee748232..3910aca5bf87 100644
--- a/js/xpconnect/wrappers/XrayWrapper.h
+++ b/js/xpconnect/wrappers/XrayWrapper.h
@@ -28,7 +28,7 @@ holder_set(JSContext *cx, JS::HandleObject holder, JS::HandleId id, bool strict,
 
 namespace XrayUtils {
 
-extern const JSClass HolderClass;
+bool IsXPCWNHolderClass(const JSClass *clasp);
 
 bool CloneExpandoChain(JSContext *cx, JSObject *src, JSObject *dst);