From 6f2dea22eebac012da24d8dbd29e8470ce1c38c6 Mon Sep 17 00:00:00 2001
From: Steve Fink <sfink@mozilla.com>
Date: Wed, 18 Jul 2012 14:32:39 -0700
Subject: [PATCH] Bug 776635 - Allow use of JSRootedObject using only external
headers. r=billm
Currently, JS::Rooted<JSObject*> requires the full definition of JSObject to be available (due to RootMethods<JSObject*>::kind() calling JSObject::rootKind()). This patch switches to using a RootKind<T> template that is explicitly specialized in jspubtd.h for externally-visible pointer types, but still falls back on T::rootKind() for other pointer types so that we don't need to explicitly specialize on eg all subclasses of JSString or JSObject.
--HG--
extra : rebase_source : 138a859babc1aac60e61fe6f08089d8dbb4995d2
---
js/src/gc/Root.h | 10 +++++++++-
js/src/jspubtd.h | 14 ++++++++++++++
js/src/jsscope.h | 3 +++
3 files changed, 26 insertions(+), 1 deletion(-)
diff --git a/js/src/gc/Root.h b/js/src/gc/Root.h
index e063d202a70f..ecf4640e2ef4 100644
--- a/js/src/gc/Root.h
+++ b/js/src/gc/Root.h
@@ -221,11 +221,19 @@ class MutableHandle : public MutableHandleBase<T>
typedef MutableHandle<JSObject*> MutableHandleObject;
typedef MutableHandle<Value> MutableHandleValue;
+/*
+ * By default, pointers should use the inheritance hierarchy to find their
+ * ThingRootKind. Some pointer types are explicitly set in jspubtd.h so that
+ * Rooted<T> may be used without the class definition being available.
+ */
+template <typename T>
+struct RootKind<T *> { static ThingRootKind rootKind() { return T::rootKind(); }; };
+
template <typename T>
struct RootMethods<T *>
{
static T *initial() { return NULL; }
- static ThingRootKind kind() { return T::rootKind(); }
+ static ThingRootKind kind() { return RootKind<T *>::rootKind(); }
static bool poisoned(T *v) { return IsPoisonedPtr(v); }
};
diff --git a/js/src/jspubtd.h b/js/src/jspubtd.h
index 45864ca0d695..7ba52f829188 100644
--- a/js/src/jspubtd.h
+++ b/js/src/jspubtd.h
@@ -240,6 +240,20 @@ enum ThingRootKind
THING_ROOT_LIMIT
};
+template <typename T>
+struct RootKind;
+
+/*
+ * Specifically mark the ThingRootKind of externally visible types, so that
+ * JSAPI users may use JSRooted... types without having the class definition
+ * available.
+ */
+template <> struct RootKind<JSObject *> { static ThingRootKind rootKind() { return THING_ROOT_OBJECT; }; };
+template <> struct RootKind<JSString *> { static ThingRootKind rootKind() { return THING_ROOT_STRING; }; };
+template <> struct RootKind<JSScript *> { static ThingRootKind rootKind() { return THING_ROOT_SCRIPT; }; };
+template <> struct RootKind<jsid> { static ThingRootKind rootKind() { return THING_ROOT_ID; }; };
+template <> struct RootKind<Value> { static ThingRootKind rootKind() { return THING_ROOT_VALUE; }; };
+
struct ContextFriendFields {
JSRuntime *const runtime;
diff --git a/js/src/jsscope.h b/js/src/jsscope.h
index 657c675a9c15..99820e1a5f3d 100644
--- a/js/src/jsscope.h
+++ b/js/src/jsscope.h
@@ -1182,6 +1182,9 @@ MarkNonNativePropertyFound(HandleObject obj, MutableHandleShape propp);
namespace JS {
template<> class AnchorPermitted<js::Shape *> { };
template<> class AnchorPermitted<const js::Shape *> { };
+
+ template<> struct RootKind<js::Shape *> { static ThingRootKind rootKind() { return THING_ROOT_SHAPE; }; };
+ template<> struct RootKind<js::BaseShape *> { static ThingRootKind rootKind() { return THING_ROOT_BASE_SHAPE; }; };
}
#endif /* jsscope_h___ */