Add m-esr52 at 52.6.0

1 files changed, 145 insertions, 0 deletions

diff --git a/js/src/vm/ProxyObject.h b/js/src/vm/ProxyObject.h
new file mode 100644
index 000000000..a0a929b20
--- /dev/null
+++ b/js/src/vm/ProxyObject.h
@@ -0,0 +1,145 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: set ts=8 sts=4 et sw=4 tw=99:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef vm_ProxyObject_h
+#define vm_ProxyObject_h
+
+#include "js/Proxy.h"
+#include "vm/ShapedObject.h"
+
+namespace js {
+
+/**
+ * This is the base class for the various kinds of proxy objects.  It's never
+ * instantiated.
+ *
+ * Proxy objects use ShapedObject::shape_ primarily to record flags.  Property
+ * information, &c. is all dynamically computed.
+ */
+class ProxyObject : public ShapedObject
+{
+    // GetProxyDataLayout computes the address of this field.
+    detail::ProxyDataLayout data;
+
+    void static_asserts() {
+        static_assert(sizeof(ProxyObject) == sizeof(JSObject_Slots0),
+                      "proxy object size must match GC thing size");
+        static_assert(offsetof(ProxyObject, data) == detail::ProxyDataOffset,
+                      "proxy object layout must match shadow interface");
+    }
+
+  public:
+    static ProxyObject* New(JSContext* cx, const BaseProxyHandler* handler, HandleValue priv,
+                            TaggedProto proto_, const ProxyOptions& options);
+
+    const Value& private_() {
+        return GetProxyPrivate(this);
+    }
+
+    void setCrossCompartmentPrivate(const Value& priv);
+    void setSameCompartmentPrivate(const Value& priv);
+
+    GCPtrValue* slotOfPrivate() {
+        return reinterpret_cast<GCPtrValue*>(&detail::GetProxyDataLayout(this)->values->privateSlot);
+    }
+
+    JSObject* target() const {
+        return const_cast<ProxyObject*>(this)->private_().toObjectOrNull();
+    }
+
+    const BaseProxyHandler* handler() const {
+        return GetProxyHandler(const_cast<ProxyObject*>(this));
+    }
+
+    void setHandler(const BaseProxyHandler* handler) {
+        SetProxyHandler(this, handler);
+    }
+
+    static size_t offsetOfValues() {
+        return offsetof(ProxyObject, data.values);
+    }
+    static size_t offsetOfHandler() {
+        return offsetof(ProxyObject, data.handler);
+    }
+    static size_t offsetOfExtraSlotInValues(size_t slot) {
+        MOZ_ASSERT(slot < detail::PROXY_EXTRA_SLOTS);
+        return offsetof(detail::ProxyValueArray, extraSlots) + slot * sizeof(Value);
+    }
+
+    const Value& extra(size_t n) const {
+        return GetProxyExtra(const_cast<ProxyObject*>(this), n);
+    }
+
+    void setExtra(size_t n, const Value& extra) {
+        SetProxyExtra(this, n, extra);
+    }
+
+    gc::AllocKind allocKindForTenure() const;
+    static size_t objectMovedDuringMinorGC(TenuringTracer* trc, JSObject* dst, JSObject* src);
+
+  private:
+    GCPtrValue* slotOfExtra(size_t n) {
+        MOZ_ASSERT(n < detail::PROXY_EXTRA_SLOTS);
+        return reinterpret_cast<GCPtrValue*>(&detail::GetProxyDataLayout(this)->values->extraSlots[n]);
+    }
+
+    static bool isValidProxyClass(const Class* clasp) {
+        // Since we can take classes from the outside, make sure that they
+        // are "sane". They have to quack enough like proxies for us to belive
+        // they should be treated as such.
+
+        // proxy_Trace is just a trivial wrapper around ProxyObject::trace for
+        // friend api exposure.
+
+        // Proxy classes are not allowed to have call or construct hooks directly. Their
+        // callability is instead decided by handler()->isCallable().
+        return clasp->isProxy() &&
+               clasp->isTrace(proxy_Trace) &&
+               !clasp->getCall() && !clasp->getConstruct();
+    }
+
+  public:
+    static unsigned grayLinkExtraSlot(JSObject* obj);
+
+    void renew(JSContext* cx, const BaseProxyHandler* handler, const Value& priv);
+
+    static void trace(JSTracer* trc, JSObject* obj);
+
+    void nuke();
+
+    // There is no class_ member to force specialization of JSObject::is<T>().
+    // The implementation in JSObject is incorrect for proxies since it doesn't
+    // take account of the handler type.
+    static const Class proxyClass;
+};
+
+inline bool
+IsProxyClass(const Class* clasp)
+{
+    return clasp->isProxy();
+}
+
+bool IsDerivedProxyObject(const JSObject* obj, const js::BaseProxyHandler* handler);
+
+} // namespace js
+
+template<>
+inline bool
+JSObject::is<js::ProxyObject>() const
+{
+    // Note: this method is implemented in terms of the IsProxy() friend API
+    // functions to ensure the implementations are tied together.
+    // Note 2: this specialization isn't used for subclasses of ProxyObject
+    // which must supply their own implementation.
+    return js::IsProxy(const_cast<JSObject*>(this));
+}
+
+inline bool
+js::IsDerivedProxyObject(const JSObject* obj, const js::BaseProxyHandler* handler) {
+    return obj->is<js::ProxyObject>() && obj->as<js::ProxyObject>().handler() == handler;
+}
+
+#endif /* vm_ProxyObject_h */