axmol/external/spidermonkey/include/mac/jsproxy.h

484 lines
20 KiB
C++

/* -*- 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 jsproxy_h
#define jsproxy_h
#include "mozilla/Maybe.h"
#include "jsfriendapi.h"
#include "js/CallNonGenericMethod.h"
#include "js/Class.h"
namespace js {
using JS::AutoIdVector;
using JS::CallArgs;
using JS::HandleId;
using JS::HandleObject;
using JS::HandleValue;
using JS::IsAcceptableThis;
using JS::MutableHandle;
using JS::MutableHandleObject;
using JS::MutableHandleValue;
using JS::NativeImpl;
using JS::PrivateValue;
using JS::Value;
class RegExpGuard;
class JS_FRIEND_API(Wrapper);
/*
* A proxy is a JSObject that implements generic behavior by providing custom
* implementations for each object trap. The implementation for each trap is
* provided by a C++ object stored on the proxy, known as its handler.
*
* A major use case for proxies is to forward each trap to another object,
* known as its target. The target can be an arbitrary C++ object. Not every
* proxy has the notion of a target, however.
*
* Proxy traps are grouped into fundamental and derived traps. Every proxy has
* to at least provide implementations for the fundamental traps, but the
* derived traps can be implemented in terms of the fundamental ones
* BaseProxyHandler provides implementations of the derived traps in terms of
* the (pure virtual) fundamental traps.
*
* To minimize code duplication, a set of abstract proxy handler classes is
* provided, from which other handlers may inherit. These abstract classes
* are organized in the following hierarchy:
*
* BaseProxyHandler
* |
* DirectProxyHandler
* |
* Wrapper
*/
/*
* BaseProxyHandler is the most generic kind of proxy handler. It does not make
* any assumptions about the target. Consequently, it does not provide any
* default implementation for the fundamental traps. It does, however, implement
* the derived traps in terms of the fundamental ones. This allows consumers of
* this class to define any custom behavior they want.
*/
class JS_FRIEND_API(BaseProxyHandler)
{
const void *mFamily;
bool mHasPrototype;
bool mHasPolicy;
protected:
// Subclasses may set this in their constructor.
void setHasPrototype(bool aHasPrototype) { mHasPrototype = aHasPrototype; }
void setHasPolicy(bool aHasPolicy) { mHasPolicy = aHasPolicy; }
public:
explicit BaseProxyHandler(const void *family);
virtual ~BaseProxyHandler();
bool hasPrototype() {
return mHasPrototype;
}
bool hasPolicy() {
return mHasPolicy;
}
inline const void *family() {
return mFamily;
}
static size_t offsetOfFamily() {
return offsetof(BaseProxyHandler, mFamily);
}
virtual bool isOuterWindow() {
return false;
}
virtual bool finalizeInBackground(Value priv) {
/*
* Called on creation of a proxy to determine whether its finalize
* method can be finalized on the background thread.
*/
return true;
}
/* Policy enforcement traps.
*
* enter() allows the policy to specify whether the caller may perform |act|
* on the proxy's |id| property. In the case when |act| is CALL, |id| is
* generally JSID_VOID.
*
* The |act| parameter to enter() specifies the action being performed.
* If |bp| is false, the trap suggests that the caller throw (though it
* may still decide to squelch the error).
*/
enum Action {
GET,
SET,
CALL
};
virtual bool enter(JSContext *cx, HandleObject wrapper, HandleId id, Action act,
bool *bp);
/* ES5 Harmony fundamental proxy traps. */
virtual bool preventExtensions(JSContext *cx, HandleObject proxy) = 0;
virtual bool getPropertyDescriptor(JSContext *cx, HandleObject proxy, HandleId id,
MutableHandle<JSPropertyDescriptor> desc,
unsigned flags) = 0;
virtual bool getOwnPropertyDescriptor(JSContext *cx, HandleObject proxy,
HandleId id, MutableHandle<JSPropertyDescriptor> desc,
unsigned flags) = 0;
virtual bool defineProperty(JSContext *cx, HandleObject proxy, HandleId id,
MutableHandle<JSPropertyDescriptor> desc) = 0;
virtual bool getOwnPropertyNames(JSContext *cx, HandleObject proxy,
AutoIdVector &props) = 0;
virtual bool delete_(JSContext *cx, HandleObject proxy, HandleId id, bool *bp) = 0;
virtual bool enumerate(JSContext *cx, HandleObject proxy, AutoIdVector &props) = 0;
/* ES5 Harmony derived proxy traps. */
virtual bool has(JSContext *cx, HandleObject proxy, HandleId id, bool *bp);
virtual bool hasOwn(JSContext *cx, HandleObject proxy, HandleId id, bool *bp);
virtual bool get(JSContext *cx, HandleObject proxy, HandleObject receiver,
HandleId id, MutableHandleValue vp);
virtual bool set(JSContext *cx, HandleObject proxy, HandleObject receiver,
HandleId id, bool strict, MutableHandleValue vp);
virtual bool keys(JSContext *cx, HandleObject proxy, AutoIdVector &props);
virtual bool iterate(JSContext *cx, HandleObject proxy, unsigned flags,
MutableHandleValue vp);
/* Spidermonkey extensions. */
virtual bool isExtensible(JSContext *cx, HandleObject proxy, bool *extensible) = 0;
virtual bool call(JSContext *cx, HandleObject proxy, const CallArgs &args);
virtual bool construct(JSContext *cx, HandleObject proxy, const CallArgs &args);
virtual bool nativeCall(JSContext *cx, IsAcceptableThis test, NativeImpl impl, CallArgs args);
virtual bool hasInstance(JSContext *cx, HandleObject proxy, MutableHandleValue v, bool *bp);
virtual bool objectClassIs(HandleObject obj, ESClassValue classValue, JSContext *cx);
virtual const char *className(JSContext *cx, HandleObject proxy);
virtual JSString *fun_toString(JSContext *cx, HandleObject proxy, unsigned indent);
virtual bool regexp_toShared(JSContext *cx, HandleObject proxy, RegExpGuard *g);
virtual bool defaultValue(JSContext *cx, HandleObject obj, JSType hint, MutableHandleValue vp);
virtual void finalize(JSFreeOp *fop, JSObject *proxy);
virtual bool getElementIfPresent(JSContext *cx, HandleObject obj, HandleObject receiver,
uint32_t index, MutableHandleValue vp, bool *present);
virtual bool getPrototypeOf(JSContext *cx, HandleObject proxy, MutableHandleObject protop);
// These two hooks must be overridden, or not overridden, in tandem -- no
// overriding just one!
virtual bool watch(JSContext *cx, JS::HandleObject proxy, JS::HandleId id,
JS::HandleObject callable);
virtual bool unwatch(JSContext *cx, JS::HandleObject proxy, JS::HandleId id);
/* See comment for weakmapKeyDelegateOp in js/Class.h. */
virtual JSObject *weakmapKeyDelegate(JSObject *proxy);
};
/*
* DirectProxyHandler includes a notion of a target object. All traps are
* reimplemented such that they forward their behavior to the target. This
* allows consumers of this class to forward to another object as transparently
* and efficiently as possible.
*/
class JS_PUBLIC_API(DirectProxyHandler) : public BaseProxyHandler
{
public:
explicit DirectProxyHandler(const void *family);
/* ES5 Harmony fundamental proxy traps. */
virtual bool preventExtensions(JSContext *cx, HandleObject proxy) MOZ_OVERRIDE;
virtual bool getPropertyDescriptor(JSContext *cx, HandleObject proxy, HandleId id,
MutableHandle<JSPropertyDescriptor> desc, unsigned flags) MOZ_OVERRIDE;
virtual bool getOwnPropertyDescriptor(JSContext *cx, HandleObject proxy,
HandleId id, MutableHandle<JSPropertyDescriptor> desc,
unsigned flags) MOZ_OVERRIDE;
virtual bool defineProperty(JSContext *cx, HandleObject proxy, HandleId id,
MutableHandle<JSPropertyDescriptor> desc) MOZ_OVERRIDE;
virtual bool getOwnPropertyNames(JSContext *cx, HandleObject proxy,
AutoIdVector &props) MOZ_OVERRIDE;
virtual bool delete_(JSContext *cx, HandleObject proxy, HandleId id,
bool *bp) MOZ_OVERRIDE;
virtual bool enumerate(JSContext *cx, HandleObject proxy,
AutoIdVector &props) MOZ_OVERRIDE;
/* ES5 Harmony derived proxy traps. */
virtual bool has(JSContext *cx, HandleObject proxy, HandleId id,
bool *bp) MOZ_OVERRIDE;
virtual bool hasOwn(JSContext *cx, HandleObject proxy, HandleId id,
bool *bp) MOZ_OVERRIDE;
virtual bool get(JSContext *cx, HandleObject proxy, HandleObject receiver,
HandleId id, MutableHandleValue vp) MOZ_OVERRIDE;
virtual bool set(JSContext *cx, HandleObject proxy, HandleObject receiver,
HandleId id, bool strict, MutableHandleValue vp) MOZ_OVERRIDE;
virtual bool keys(JSContext *cx, HandleObject proxy,
AutoIdVector &props) MOZ_OVERRIDE;
virtual bool iterate(JSContext *cx, HandleObject proxy, unsigned flags,
MutableHandleValue vp) MOZ_OVERRIDE;
/* Spidermonkey extensions. */
virtual bool isExtensible(JSContext *cx, HandleObject proxy, bool *extensible) MOZ_OVERRIDE;
virtual bool call(JSContext *cx, HandleObject proxy, const CallArgs &args) MOZ_OVERRIDE;
virtual bool construct(JSContext *cx, HandleObject proxy, const CallArgs &args) MOZ_OVERRIDE;
virtual bool nativeCall(JSContext *cx, IsAcceptableThis test, NativeImpl impl,
CallArgs args) MOZ_OVERRIDE;
virtual bool hasInstance(JSContext *cx, HandleObject proxy, MutableHandleValue v,
bool *bp) MOZ_OVERRIDE;
virtual bool objectClassIs(HandleObject obj, ESClassValue classValue,
JSContext *cx) MOZ_OVERRIDE;
virtual const char *className(JSContext *cx, HandleObject proxy) MOZ_OVERRIDE;
virtual JSString *fun_toString(JSContext *cx, HandleObject proxy,
unsigned indent) MOZ_OVERRIDE;
virtual bool regexp_toShared(JSContext *cx, HandleObject proxy,
RegExpGuard *g) MOZ_OVERRIDE;
virtual JSObject *weakmapKeyDelegate(JSObject *proxy);
};
/* Dispatch point for handlers that executes the appropriate C++ or scripted traps. */
class Proxy
{
public:
/* ES5 Harmony fundamental proxy traps. */
static bool preventExtensions(JSContext *cx, HandleObject proxy);
static bool getPropertyDescriptor(JSContext *cx, HandleObject proxy, HandleId id,
MutableHandle<JSPropertyDescriptor> desc, unsigned flags);
static bool getPropertyDescriptor(JSContext *cx, HandleObject proxy, unsigned flags, HandleId id,
MutableHandleValue vp);
static bool getOwnPropertyDescriptor(JSContext *cx, HandleObject proxy, HandleId id,
MutableHandle<JSPropertyDescriptor> desc, unsigned flags);
static bool getOwnPropertyDescriptor(JSContext *cx, HandleObject proxy, unsigned flags, HandleId id,
MutableHandleValue vp);
static bool defineProperty(JSContext *cx, HandleObject proxy, HandleId id,
MutableHandle<JSPropertyDescriptor> desc);
static bool defineProperty(JSContext *cx, HandleObject proxy, HandleId id, HandleValue v);
static bool getOwnPropertyNames(JSContext *cx, HandleObject proxy, AutoIdVector &props);
static bool delete_(JSContext *cx, HandleObject proxy, HandleId id, bool *bp);
static bool enumerate(JSContext *cx, HandleObject proxy, AutoIdVector &props);
/* ES5 Harmony derived proxy traps. */
static bool has(JSContext *cx, HandleObject proxy, HandleId id, bool *bp);
static bool hasOwn(JSContext *cx, HandleObject proxy, HandleId id, bool *bp);
static bool get(JSContext *cx, HandleObject proxy, HandleObject receiver, HandleId id,
MutableHandleValue vp);
static bool getElementIfPresent(JSContext *cx, HandleObject proxy, HandleObject receiver,
uint32_t index, MutableHandleValue vp, bool *present);
static bool set(JSContext *cx, HandleObject proxy, HandleObject receiver, HandleId id,
bool strict, MutableHandleValue vp);
static bool keys(JSContext *cx, HandleObject proxy, AutoIdVector &props);
static bool iterate(JSContext *cx, HandleObject proxy, unsigned flags, MutableHandleValue vp);
/* Spidermonkey extensions. */
static bool isExtensible(JSContext *cx, HandleObject proxy, bool *extensible);
static bool call(JSContext *cx, HandleObject proxy, const CallArgs &args);
static bool construct(JSContext *cx, HandleObject proxy, const CallArgs &args);
static bool nativeCall(JSContext *cx, IsAcceptableThis test, NativeImpl impl, CallArgs args);
static bool hasInstance(JSContext *cx, HandleObject proxy, MutableHandleValue v, bool *bp);
static bool objectClassIs(HandleObject obj, ESClassValue classValue, JSContext *cx);
static const char *className(JSContext *cx, HandleObject proxy);
static JSString *fun_toString(JSContext *cx, HandleObject proxy, unsigned indent);
static bool regexp_toShared(JSContext *cx, HandleObject proxy, RegExpGuard *g);
static bool defaultValue(JSContext *cx, HandleObject obj, JSType hint, MutableHandleValue vp);
static bool getPrototypeOf(JSContext *cx, HandleObject proxy, MutableHandleObject protop);
static bool watch(JSContext *cx, JS::HandleObject proxy, JS::HandleId id,
JS::HandleObject callable);
static bool unwatch(JSContext *cx, JS::HandleObject proxy, JS::HandleId id);
/* IC entry path for handling __noSuchMethod__ on access. */
static bool callProp(JSContext *cx, HandleObject proxy, HandleObject reveiver, HandleId id,
MutableHandleValue vp);
static JSObject * const LazyProto;
};
// Use these in places where you don't want to #include vm/ProxyObject.h.
extern JS_FRIEND_DATA(const js::Class* const) CallableProxyClassPtr;
extern JS_FRIEND_DATA(const js::Class* const) UncallableProxyClassPtr;
extern JS_FRIEND_DATA(const js::Class* const) OuterWindowProxyClassPtr;
inline bool IsProxyClass(const Class *clasp)
{
return clasp == CallableProxyClassPtr ||
clasp == UncallableProxyClassPtr ||
clasp == OuterWindowProxyClassPtr;
}
inline bool IsProxy(JSObject *obj)
{
return IsProxyClass(GetObjectClass(obj));
}
/*
* These are part of the API.
*
* NOTE: PROXY_PRIVATE_SLOT is 0 because that way slot 0 is usable by API
* clients for both proxy and non-proxy objects. So an API client that only
* needs to store one slot's worth of data doesn't need to branch on what sort
* of object it has.
*/
const uint32_t PROXY_PRIVATE_SLOT = 0;
const uint32_t PROXY_HANDLER_SLOT = 1;
const uint32_t PROXY_EXTRA_SLOT = 2;
inline BaseProxyHandler *
GetProxyHandler(JSObject *obj)
{
JS_ASSERT(IsProxy(obj));
return (BaseProxyHandler *) GetReservedSlot(obj, PROXY_HANDLER_SLOT).toPrivate();
}
inline const Value &
GetProxyPrivate(JSObject *obj)
{
JS_ASSERT(IsProxy(obj));
return GetReservedSlot(obj, PROXY_PRIVATE_SLOT);
}
inline JSObject *
GetProxyTargetObject(JSObject *obj)
{
JS_ASSERT(IsProxy(obj));
return GetProxyPrivate(obj).toObjectOrNull();
}
inline const Value &
GetProxyExtra(JSObject *obj, size_t n)
{
JS_ASSERT(IsProxy(obj));
return GetReservedSlot(obj, PROXY_EXTRA_SLOT + n);
}
inline void
SetProxyHandler(JSObject *obj, BaseProxyHandler *handler)
{
JS_ASSERT(IsProxy(obj));
SetReservedSlot(obj, PROXY_HANDLER_SLOT, PrivateValue(handler));
}
inline void
SetProxyExtra(JSObject *obj, size_t n, const Value &extra)
{
JS_ASSERT(IsProxy(obj));
JS_ASSERT(n <= 1);
SetReservedSlot(obj, PROXY_EXTRA_SLOT + n, extra);
}
class MOZ_STACK_CLASS ProxyOptions {
public:
ProxyOptions() : callable_(false),
singleton_(false),
forceForegroundFinalization_(false)
{}
bool callable() const { return callable_; }
ProxyOptions &setCallable(bool flag) {
callable_ = flag;
return *this;
}
bool singleton() const { return singleton_; }
ProxyOptions &setSingleton(bool flag) {
singleton_ = flag;
return *this;
}
bool forceForegroundFinalization() const {
return forceForegroundFinalization_;
}
ProxyOptions &setForceForegroundFinalization(bool flag) {
forceForegroundFinalization_ = true;
return *this;
}
private:
bool callable_;
bool singleton_;
bool forceForegroundFinalization_;
};
JS_FRIEND_API(JSObject *)
NewProxyObject(JSContext *cx, BaseProxyHandler *handler, HandleValue priv,
JSObject *proto, JSObject *parent, const ProxyOptions &options = ProxyOptions());
JSObject *
RenewProxyObject(JSContext *cx, JSObject *obj, BaseProxyHandler *handler, Value priv);
class JS_FRIEND_API(AutoEnterPolicy)
{
public:
typedef BaseProxyHandler::Action Action;
AutoEnterPolicy(JSContext *cx, BaseProxyHandler *handler,
HandleObject wrapper, HandleId id, Action act, bool mayThrow)
#ifdef DEBUG
: context(nullptr)
#endif
{
allow = handler->hasPolicy() ? handler->enter(cx, wrapper, id, act, &rv)
: true;
recordEnter(cx, wrapper, id);
// We want to throw an exception if all of the following are true:
// * The policy disallowed access.
// * The policy set rv to false, indicating that we should throw.
// * The caller did not instruct us to ignore exceptions.
// * The policy did not throw itself.
if (!allow && !rv && mayThrow)
reportErrorIfExceptionIsNotPending(cx, id);
}
virtual ~AutoEnterPolicy() { recordLeave(); }
inline bool allowed() { return allow; }
inline bool returnValue() { JS_ASSERT(!allowed()); return rv; }
protected:
// no-op constructor for subclass
AutoEnterPolicy()
#ifdef DEBUG
: context(nullptr)
#endif
{};
void reportErrorIfExceptionIsNotPending(JSContext *cx, jsid id);
bool allow;
bool rv;
#ifdef DEBUG
JSContext *context;
mozilla::Maybe<HandleObject> enteredProxy;
mozilla::Maybe<HandleId> enteredId;
// NB: We explicitly don't track the entered action here, because sometimes
// SET traps do an implicit GET during their implementation, leading to
// spurious assertions.
AutoEnterPolicy *prev;
void recordEnter(JSContext *cx, HandleObject proxy, HandleId id);
void recordLeave();
friend JS_FRIEND_API(void) assertEnteredPolicy(JSContext *cx, JSObject *proxy, jsid id);
#else
inline void recordEnter(JSContext *cx, JSObject *proxy, jsid id) {}
inline void recordLeave() {}
#endif
};
#ifdef DEBUG
class JS_FRIEND_API(AutoWaivePolicy) : public AutoEnterPolicy {
public:
AutoWaivePolicy(JSContext *cx, HandleObject proxy, HandleId id)
{
allow = true;
recordEnter(cx, proxy, id);
}
};
#else
class JS_FRIEND_API(AutoWaivePolicy) {
public: AutoWaivePolicy(JSContext *cx, HandleObject proxy, HandleId id) {};
};
#endif
} /* namespace js */
extern JS_FRIEND_API(JSObject *)
js_InitProxyClass(JSContext *cx, JS::HandleObject obj);
#endif /* jsproxy_h */