1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/js/xpconnect/src/XPCQuickStubs.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,644 @@
1.4 +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
1.5 +/* vim: set ts=8 sts=4 et sw=4 tw=99: */
1.6 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +#ifndef xpcquickstubs_h___
1.11 +#define xpcquickstubs_h___
1.12 +
1.13 +#include "XPCForwards.h"
1.14 +
1.15 +class qsObjectHelper;
1.16 +namespace mozilla {
1.17 +namespace dom {
1.18 +class NativePropertiesHolder;
1.19 +}
1.20 +}
1.21 +
1.22 +/* XPCQuickStubs.h - Support functions used only by quick stubs. */
1.23 +
1.24 +class XPCCallContext;
1.25 +
1.26 +#define XPC_QS_NULL_INDEX ((uint16_t) -1)
1.27 +
1.28 +struct xpc_qsPropertySpec {
1.29 + uint16_t name_index;
1.30 + JSNative getter;
1.31 + JSNative setter;
1.32 +};
1.33 +
1.34 +struct xpc_qsFunctionSpec {
1.35 + uint16_t name_index;
1.36 + uint16_t arity;
1.37 + JSNative native;
1.38 +};
1.39 +
1.40 +/** A table mapping interfaces to quick stubs. */
1.41 +struct xpc_qsHashEntry {
1.42 + nsID iid;
1.43 + uint16_t prop_index;
1.44 + uint16_t n_props;
1.45 + uint16_t func_index;
1.46 + uint16_t n_funcs;
1.47 + const mozilla::dom::NativePropertiesHolder* newBindingProperties;
1.48 + // These last two fields index to other entries in the same table.
1.49 + // XPC_QS_NULL_ENTRY indicates there are no more entries in the chain.
1.50 + uint16_t parentInterface;
1.51 + uint16_t chain;
1.52 +};
1.53 +
1.54 +bool
1.55 +xpc_qsDefineQuickStubs(JSContext *cx, JSObject *proto, unsigned extraFlags,
1.56 + uint32_t ifacec, const nsIID **interfaces,
1.57 + uint32_t tableSize, const xpc_qsHashEntry *table,
1.58 + const xpc_qsPropertySpec *propspecs,
1.59 + const xpc_qsFunctionSpec *funcspecs,
1.60 + const char *stringTable);
1.61 +
1.62 +/** Raise an exception on @a cx and return false. */
1.63 +bool
1.64 +xpc_qsThrow(JSContext *cx, nsresult rv);
1.65 +
1.66 +/**
1.67 + * Fail after an XPCOM getter or setter returned rv.
1.68 + *
1.69 + * NOTE: Here @a obj must be the JSObject whose private data field points to an
1.70 + * XPCWrappedNative, not merely an object that has an XPCWrappedNative
1.71 + * somewhere along the prototype chain! The same applies to @a obj in
1.72 + * xpc_qsThrowBadSetterValue and <code>vp[1]</code> in xpc_qsThrowMethodFailed
1.73 + * and xpc_qsThrowBadArg.
1.74 + *
1.75 + * This is one reason the UnwrapThis functions below have an out parameter that
1.76 + * receives the wrapper JSObject. (The other reason is to help the caller keep
1.77 + * that JSObject GC-reachable.)
1.78 + */
1.79 +bool
1.80 +xpc_qsThrowGetterSetterFailed(JSContext *cx, nsresult rv,
1.81 + JSObject *obj, jsid memberId);
1.82 +// And variants using strings and string tables
1.83 +bool
1.84 +xpc_qsThrowGetterSetterFailed(JSContext *cx, nsresult rv,
1.85 + JSObject *obj, const char* memberName);
1.86 +bool
1.87 +xpc_qsThrowGetterSetterFailed(JSContext *cx, nsresult rv,
1.88 + JSObject *obj, uint16_t memberIndex);
1.89 +
1.90 +/**
1.91 + * Fail after an XPCOM method returned rv.
1.92 + *
1.93 + * See NOTE at xpc_qsThrowGetterSetterFailed.
1.94 + */
1.95 +bool
1.96 +xpc_qsThrowMethodFailed(JSContext *cx, nsresult rv, jsval *vp);
1.97 +
1.98 +/**
1.99 + * Fail after converting a method argument fails.
1.100 + *
1.101 + * See NOTE at xpc_qsThrowGetterSetterFailed.
1.102 + */
1.103 +void
1.104 +xpc_qsThrowBadArg(JSContext *cx, nsresult rv, jsval *vp, unsigned paramnum);
1.105 +
1.106 +void
1.107 +xpc_qsThrowBadArgWithCcx(XPCCallContext &ccx, nsresult rv, unsigned paramnum);
1.108 +
1.109 +void
1.110 +xpc_qsThrowBadArgWithDetails(JSContext *cx, nsresult rv, unsigned paramnum,
1.111 + const char *ifaceName, const char *memberName);
1.112 +
1.113 +/**
1.114 + * Fail after converting a setter argument fails.
1.115 + *
1.116 + * See NOTE at xpc_qsThrowGetterSetterFailed.
1.117 + */
1.118 +void
1.119 +xpc_qsThrowBadSetterValue(JSContext *cx, nsresult rv, JSObject *obj,
1.120 + jsid propId);
1.121 +// And variants using strings and string tables
1.122 +void
1.123 +xpc_qsThrowBadSetterValue(JSContext *cx, nsresult rv, JSObject *obj,
1.124 + const char* propName);
1.125 +void
1.126 +xpc_qsThrowBadSetterValue(JSContext *cx, nsresult rv, JSObject *obj,
1.127 + uint16_t name_index);
1.128 +
1.129 +
1.130 +bool
1.131 +xpc_qsGetterOnlyPropertyStub(JSContext *cx, JS::HandleObject obj, JS::HandleId id,
1.132 + bool strict, JS::MutableHandleValue vp);
1.133 +
1.134 +bool
1.135 +xpc_qsGetterOnlyNativeStub(JSContext *cx, unsigned argc, jsval *vp);
1.136 +
1.137 +/* Functions for converting values between COM and JS. */
1.138 +
1.139 +inline bool
1.140 +xpc_qsInt64ToJsval(JSContext *cx, int64_t i, JS::MutableHandleValue rv)
1.141 +{
1.142 + rv.setNumber(static_cast<double>(i));
1.143 + return true;
1.144 +}
1.145 +
1.146 +inline bool
1.147 +xpc_qsUint64ToJsval(JSContext *cx, uint64_t u, JS::MutableHandleValue rv)
1.148 +{
1.149 + rv.setNumber(static_cast<double>(u));
1.150 + return true;
1.151 +}
1.152 +
1.153 +
1.154 +/* Classes for converting jsvals to string types. */
1.155 +
1.156 +template <class S, class T>
1.157 +class xpc_qsBasicString
1.158 +{
1.159 +public:
1.160 + typedef S interface_type;
1.161 + typedef T implementation_type;
1.162 +
1.163 + ~xpc_qsBasicString()
1.164 + {
1.165 + if (mValid)
1.166 + Ptr()->~implementation_type();
1.167 + }
1.168 +
1.169 + bool IsValid() const { return mValid; }
1.170 +
1.171 + implementation_type *Ptr()
1.172 + {
1.173 + MOZ_ASSERT(mValid);
1.174 + return reinterpret_cast<implementation_type *>(mBuf);
1.175 + }
1.176 +
1.177 + const implementation_type *Ptr() const
1.178 + {
1.179 + MOZ_ASSERT(mValid);
1.180 + return reinterpret_cast<const implementation_type *>(mBuf);
1.181 + }
1.182 +
1.183 + operator interface_type &()
1.184 + {
1.185 + MOZ_ASSERT(mValid);
1.186 + return *Ptr();
1.187 + }
1.188 +
1.189 + operator const interface_type &() const
1.190 + {
1.191 + MOZ_ASSERT(mValid);
1.192 + return *Ptr();
1.193 + }
1.194 +
1.195 + /* Enum that defines how JS |null| and |undefined| should be treated. See
1.196 + * the WebIDL specification. eStringify means convert to the string "null"
1.197 + * or "undefined" respectively, via the standard JS ToString() operation;
1.198 + * eEmpty means convert to the string ""; eNull means convert to an empty
1.199 + * string with the void bit set.
1.200 + *
1.201 + * Per webidl the default behavior of an unannotated interface is
1.202 + * eStringify, but our de-facto behavior has been eNull for |null| and
1.203 + * eStringify for |undefined|, so leaving it that way for now. If we ever
1.204 + * get to a point where we go through and annotate our interfaces as
1.205 + * needed, we can change that.
1.206 + */
1.207 + enum StringificationBehavior {
1.208 + eStringify,
1.209 + eEmpty,
1.210 + eNull,
1.211 + eDefaultNullBehavior = eNull,
1.212 + eDefaultUndefinedBehavior = eStringify
1.213 + };
1.214 +
1.215 +protected:
1.216 + /*
1.217 + * Neither field is initialized; that is left to the derived class
1.218 + * constructor. However, the destructor destroys the string object
1.219 + * stored in mBuf, if mValid is true.
1.220 + */
1.221 + void *mBuf[JS_HOWMANY(sizeof(implementation_type), sizeof(void *))];
1.222 + bool mValid;
1.223 +
1.224 + /*
1.225 + * If null is returned, then we either failed or fully initialized
1.226 + * |this|; in either case the caller should return immediately
1.227 + * without doing anything else. Otherwise, the JSString* created
1.228 + * from |v| will be returned. It'll be rooted, as needed, in
1.229 + * *pval. nullBehavior and undefinedBehavior control what happens
1.230 + * when |v| is JSVAL_IS_NULL and JSVAL_IS_VOID respectively.
1.231 + */
1.232 + template<class traits>
1.233 + JSString* InitOrStringify(JSContext* cx, JS::HandleValue v,
1.234 + JS::MutableHandleValue pval,
1.235 + bool notpassed,
1.236 + StringificationBehavior nullBehavior,
1.237 + StringificationBehavior undefinedBehavior) {
1.238 + JSString *s;
1.239 + if (JSVAL_IS_STRING(v)) {
1.240 + s = JSVAL_TO_STRING(v);
1.241 + } else {
1.242 + StringificationBehavior behavior = eStringify;
1.243 + if (JSVAL_IS_NULL(v)) {
1.244 + behavior = nullBehavior;
1.245 + } else if (JSVAL_IS_VOID(v)) {
1.246 + behavior = undefinedBehavior;
1.247 + }
1.248 +
1.249 + // If pval is null, that means the argument was optional and
1.250 + // not passed; turn those into void strings if they're
1.251 + // supposed to be stringified.
1.252 + if (behavior != eStringify || notpassed) {
1.253 + // Here behavior == eStringify implies notpassed, so both eNull and
1.254 + // eStringify should end up with void strings.
1.255 + (new(mBuf) implementation_type(traits::sEmptyBuffer, uint32_t(0)))->
1.256 + SetIsVoid(behavior != eEmpty);
1.257 + mValid = true;
1.258 + return nullptr;
1.259 + }
1.260 +
1.261 + s = JS::ToString(cx, v);
1.262 + if (!s) {
1.263 + mValid = false;
1.264 + return nullptr;
1.265 + }
1.266 + pval.setString(s); // Root the new string.
1.267 + }
1.268 +
1.269 + return s;
1.270 + }
1.271 +};
1.272 +
1.273 +/**
1.274 + * Class for converting a jsval to DOMString.
1.275 + *
1.276 + * xpc_qsDOMString arg0(cx, &argv[0]);
1.277 + * if (!arg0.IsValid())
1.278 + * return false;
1.279 + *
1.280 + * The second argument to the constructor is an in-out parameter. It must
1.281 + * point to a rooted jsval, such as a JSNative argument or return value slot.
1.282 + * The value in the jsval on entry is converted to a string. The constructor
1.283 + * may overwrite that jsval with a string value, to protect the characters of
1.284 + * the string from garbage collection. The caller must leave the jsval alone
1.285 + * for the lifetime of the xpc_qsDOMString.
1.286 + */
1.287 +class xpc_qsDOMString : public xpc_qsBasicString<nsAString, nsDependentString>
1.288 +{
1.289 +public:
1.290 + xpc_qsDOMString(JSContext *cx, JS::HandleValue v,
1.291 + JS::MutableHandleValue pval, bool notpassed,
1.292 + StringificationBehavior nullBehavior,
1.293 + StringificationBehavior undefinedBehavior);
1.294 +};
1.295 +
1.296 +/**
1.297 + * The same as xpc_qsDOMString, but with slightly different conversion behavior,
1.298 + * corresponding to the [astring] magic XPIDL annotation rather than [domstring].
1.299 + */
1.300 +class xpc_qsAString : public xpc_qsDOMString
1.301 +{
1.302 +public:
1.303 + xpc_qsAString(JSContext *cx, JS::HandleValue v,
1.304 + JS::MutableHandleValue pval, bool notpassed)
1.305 + : xpc_qsDOMString(cx, v, pval, notpassed, eNull, eNull)
1.306 + {}
1.307 +};
1.308 +
1.309 +/**
1.310 + * Like xpc_qsDOMString and xpc_qsAString, but for XPIDL native types annotated
1.311 + * with [cstring] rather than [domstring] or [astring].
1.312 + */
1.313 +class xpc_qsACString : public xpc_qsBasicString<nsACString, nsCString>
1.314 +{
1.315 +public:
1.316 + xpc_qsACString(JSContext *cx, JS::HandleValue v,
1.317 + JS::MutableHandleValue pval, bool notpassed,
1.318 + StringificationBehavior nullBehavior = eNull,
1.319 + StringificationBehavior undefinedBehavior = eNull);
1.320 +};
1.321 +
1.322 +/**
1.323 + * And similar for AUTF8String.
1.324 + */
1.325 +class xpc_qsAUTF8String :
1.326 + public xpc_qsBasicString<nsACString, NS_ConvertUTF16toUTF8>
1.327 +{
1.328 +public:
1.329 + xpc_qsAUTF8String(JSContext* cx, JS::HandleValue v,
1.330 + JS::MutableHandleValue pval, bool notpassed);
1.331 +};
1.332 +
1.333 +struct xpc_qsSelfRef
1.334 +{
1.335 + xpc_qsSelfRef() : ptr(nullptr) {}
1.336 + explicit xpc_qsSelfRef(nsISupports *p) : ptr(p) {}
1.337 + ~xpc_qsSelfRef() { NS_IF_RELEASE(ptr); }
1.338 +
1.339 + nsISupports* ptr;
1.340 +};
1.341 +
1.342 +/**
1.343 + * Convert a jsval to char*, returning true on success.
1.344 + *
1.345 + * @param cx
1.346 + * A context.
1.347 + * @param v
1.348 + * A value to convert.
1.349 + * @param bytes
1.350 + * Out. On success it receives the converted string unless v is null or
1.351 + * undefinedin which case bytes->ptr() remains null.
1.352 + */
1.353 +bool
1.354 +xpc_qsJsvalToCharStr(JSContext *cx, jsval v, JSAutoByteString *bytes);
1.355 +
1.356 +bool
1.357 +xpc_qsJsvalToWcharStr(JSContext *cx, jsval v, JS::MutableHandleValue pval, const char16_t **pstr);
1.358 +
1.359 +
1.360 +nsresult
1.361 +getWrapper(JSContext *cx,
1.362 + JSObject *obj,
1.363 + XPCWrappedNative **wrapper,
1.364 + JSObject **cur,
1.365 + XPCWrappedNativeTearOff **tearoff);
1.366 +
1.367 +nsresult
1.368 +castNative(JSContext *cx,
1.369 + XPCWrappedNative *wrapper,
1.370 + JSObject *cur,
1.371 + XPCWrappedNativeTearOff *tearoff,
1.372 + const nsIID &iid,
1.373 + void **ppThis,
1.374 + nsISupports **ppThisRef,
1.375 + JS::MutableHandleValue vp);
1.376 +
1.377 +/**
1.378 + * Search @a obj and its prototype chain for an XPCOM object that implements
1.379 + * the interface T.
1.380 + *
1.381 + * If an object implementing T is found, store a reference to the wrapper
1.382 + * JSObject in @a *pThisVal, store a pointer to the T in @a *ppThis, and return
1.383 + * true. Otherwise, raise an exception on @a cx and return false.
1.384 + *
1.385 + * @a *pThisRef receives the same pointer as *ppThis if the T was AddRefed.
1.386 + * Otherwise it receives null (even on error).
1.387 + *
1.388 + * This supports split objects and XPConnect tear-offs and it sees through
1.389 + * XOWs, XPCNativeWrappers, and SafeJSObjectWrappers.
1.390 + *
1.391 + * Requires a request on @a cx.
1.392 + */
1.393 +template <class T>
1.394 +inline bool
1.395 +xpc_qsUnwrapThis(JSContext *cx,
1.396 + JS::HandleObject obj,
1.397 + T **ppThis,
1.398 + nsISupports **pThisRef,
1.399 + JS::MutableHandleValue pThisVal,
1.400 + bool failureFatal = true)
1.401 +{
1.402 + XPCWrappedNative *wrapper;
1.403 + XPCWrappedNativeTearOff *tearoff;
1.404 + JS::RootedObject current(cx);
1.405 + nsresult rv = getWrapper(cx, obj, &wrapper, current.address(), &tearoff);
1.406 + if (NS_SUCCEEDED(rv))
1.407 + rv = castNative(cx, wrapper, current, tearoff, NS_GET_TEMPLATE_IID(T),
1.408 + reinterpret_cast<void **>(ppThis), pThisRef, pThisVal);
1.409 +
1.410 + if (failureFatal)
1.411 + return NS_SUCCEEDED(rv) || xpc_qsThrow(cx, rv);
1.412 +
1.413 + if (NS_FAILED(rv))
1.414 + *ppThis = nullptr;
1.415 + return true;
1.416 +}
1.417 +
1.418 +nsISupports*
1.419 +castNativeFromWrapper(JSContext *cx,
1.420 + JSObject *obj,
1.421 + uint32_t interfaceBit,
1.422 + uint32_t protoID,
1.423 + int32_t protoDepth,
1.424 + nsISupports **pRef,
1.425 + JS::MutableHandleValue pVal,
1.426 + nsresult *rv);
1.427 +
1.428 +bool
1.429 +xpc_qsUnwrapThisFromCcxImpl(XPCCallContext &ccx,
1.430 + const nsIID &iid,
1.431 + void **ppThis,
1.432 + nsISupports **pThisRef,
1.433 + JS::MutableHandleValue vp);
1.434 +
1.435 +/**
1.436 + * Alternate implementation of xpc_qsUnwrapThis using information already
1.437 + * present in the given XPCCallContext.
1.438 + */
1.439 +template <class T>
1.440 +inline bool
1.441 +xpc_qsUnwrapThisFromCcx(XPCCallContext &ccx,
1.442 + T **ppThis,
1.443 + nsISupports **pThisRef,
1.444 + JS::MutableHandleValue pThisVal)
1.445 +{
1.446 + return xpc_qsUnwrapThisFromCcxImpl(ccx,
1.447 + NS_GET_TEMPLATE_IID(T),
1.448 + reinterpret_cast<void **>(ppThis),
1.449 + pThisRef,
1.450 + pThisVal);
1.451 +}
1.452 +
1.453 +MOZ_ALWAYS_INLINE JSObject*
1.454 +xpc_qsUnwrapObj(jsval v, nsISupports **ppArgRef, nsresult *rv)
1.455 +{
1.456 + *rv = NS_OK;
1.457 + if (v.isObject()) {
1.458 + return &v.toObject();
1.459 + }
1.460 +
1.461 + if (!v.isNullOrUndefined()) {
1.462 + *rv = ((v.isInt32() && v.toInt32() == 0)
1.463 + ? NS_ERROR_XPC_BAD_CONVERT_JS_ZERO_ISNOT_NULL
1.464 + : NS_ERROR_XPC_BAD_CONVERT_JS);
1.465 + }
1.466 +
1.467 + *ppArgRef = nullptr;
1.468 + return nullptr;
1.469 +}
1.470 +
1.471 +nsresult
1.472 +xpc_qsUnwrapArgImpl(JSContext *cx, JS::HandleValue v, const nsIID &iid, void **ppArg,
1.473 + nsISupports **ppArgRef, JS::MutableHandleValue vp);
1.474 +
1.475 +/** Convert a jsval to an XPCOM pointer. */
1.476 +template <class Interface, class StrongRefType>
1.477 +inline nsresult
1.478 +xpc_qsUnwrapArg(JSContext *cx, JS::HandleValue v, Interface **ppArg,
1.479 + StrongRefType **ppArgRef, JS::MutableHandleValue vp)
1.480 +{
1.481 + nsISupports* argRef = *ppArgRef;
1.482 + nsresult rv = xpc_qsUnwrapArgImpl(cx, v, NS_GET_TEMPLATE_IID(Interface),
1.483 + reinterpret_cast<void **>(ppArg), &argRef,
1.484 + vp);
1.485 + *ppArgRef = static_cast<StrongRefType*>(argRef);
1.486 + return rv;
1.487 +}
1.488 +
1.489 +MOZ_ALWAYS_INLINE nsISupports*
1.490 +castNativeArgFromWrapper(JSContext *cx,
1.491 + jsval v,
1.492 + uint32_t bit,
1.493 + uint32_t protoID,
1.494 + int32_t protoDepth,
1.495 + nsISupports **pArgRef,
1.496 + JS::MutableHandleValue vp,
1.497 + nsresult *rv)
1.498 +{
1.499 + JSObject *src = xpc_qsUnwrapObj(v, pArgRef, rv);
1.500 + if (!src)
1.501 + return nullptr;
1.502 +
1.503 + return castNativeFromWrapper(cx, src, bit, protoID, protoDepth, pArgRef, vp, rv);
1.504 +}
1.505 +
1.506 +inline nsWrapperCache*
1.507 +xpc_qsGetWrapperCache(nsWrapperCache *cache)
1.508 +{
1.509 + return cache;
1.510 +}
1.511 +
1.512 +inline nsWrapperCache*
1.513 +xpc_qsGetWrapperCache(void *p)
1.514 +{
1.515 + return nullptr;
1.516 +}
1.517 +
1.518 +/** Convert an XPCOM pointer to jsval. Return true on success.
1.519 + * aIdentity is a performance optimization. Set it to true,
1.520 + * only if p is the identity pointer.
1.521 + */
1.522 +bool
1.523 +xpc_qsXPCOMObjectToJsval(JSContext *aCx,
1.524 + qsObjectHelper &aHelper,
1.525 + const nsIID *iid,
1.526 + XPCNativeInterface **iface,
1.527 + JS::MutableHandleValue rval);
1.528 +
1.529 +/**
1.530 + * Convert a variant to jsval. Return true on success.
1.531 + */
1.532 +bool
1.533 +xpc_qsVariantToJsval(JSContext *cx,
1.534 + nsIVariant *p,
1.535 + JS::MutableHandleValue rval);
1.536 +
1.537 +#ifdef DEBUG
1.538 +void
1.539 +xpc_qsAssertContextOK(JSContext *cx);
1.540 +
1.541 +inline bool
1.542 +xpc_qsSameResult(nsISupports *result1, nsISupports *result2)
1.543 +{
1.544 + return SameCOMIdentity(result1, result2);
1.545 +}
1.546 +
1.547 +inline bool
1.548 +xpc_qsSameResult(const nsString &result1, const nsString &result2)
1.549 +{
1.550 + return result1.Equals(result2);
1.551 +}
1.552 +
1.553 +inline bool
1.554 +xpc_qsSameResult(int32_t result1, int32_t result2)
1.555 +{
1.556 + return result1 == result2;
1.557 +}
1.558 +
1.559 +#define XPC_QS_ASSERT_CONTEXT_OK(cx) xpc_qsAssertContextOK(cx)
1.560 +#else
1.561 +#define XPC_QS_ASSERT_CONTEXT_OK(cx) ((void) 0)
1.562 +#endif
1.563 +
1.564 +// Apply |op| to |obj|, |id|, and |vp|. If |op| is a setter, treat the assignment as lenient.
1.565 +template<typename Op>
1.566 +inline bool ApplyPropertyOp(JSContext *cx, Op op, JS::HandleObject obj, JS::HandleId id,
1.567 + JS::MutableHandleValue vp);
1.568 +
1.569 +template<>
1.570 +inline bool
1.571 +ApplyPropertyOp<JSPropertyOp>(JSContext *cx, JSPropertyOp op, JS::HandleObject obj, JS::HandleId id,
1.572 + JS::MutableHandleValue vp)
1.573 +{
1.574 + return op(cx, obj, id, vp);
1.575 +}
1.576 +
1.577 +template<>
1.578 +inline bool
1.579 +ApplyPropertyOp<JSStrictPropertyOp>(JSContext *cx, JSStrictPropertyOp op, JS::HandleObject obj,
1.580 + JS::HandleId id, JS::MutableHandleValue vp)
1.581 +{
1.582 + return op(cx, obj, id, true, vp);
1.583 +}
1.584 +
1.585 +template<typename Op>
1.586 +bool
1.587 +PropertyOpForwarder(JSContext *cx, unsigned argc, jsval *vp)
1.588 +{
1.589 + // Layout:
1.590 + // this = our this
1.591 + // property op to call = callee reserved slot 0
1.592 + // name of the property = callee reserved slot 1
1.593 +
1.594 + JS::CallArgs args = CallArgsFromVp(argc, vp);
1.595 +
1.596 + JS::RootedObject callee(cx, &args.callee());
1.597 + JS::RootedObject obj(cx, JS_THIS_OBJECT(cx, vp));
1.598 + if (!obj)
1.599 + return false;
1.600 +
1.601 + JS::RootedValue v(cx, js::GetFunctionNativeReserved(callee, 0));
1.602 +
1.603 + JSObject *ptrobj = JSVAL_TO_OBJECT(v);
1.604 + Op *popp = static_cast<Op *>(JS_GetPrivate(ptrobj));
1.605 +
1.606 + v = js::GetFunctionNativeReserved(callee, 1);
1.607 +
1.608 + JS::RootedValue argval(cx, args.get(0));
1.609 + JS::RootedId id(cx);
1.610 + if (!JS_ValueToId(cx, v, &id))
1.611 + return false;
1.612 + args.rval().set(argval);
1.613 + return ApplyPropertyOp<Op>(cx, *popp, obj, id, args.rval());
1.614 +}
1.615 +
1.616 +extern const JSClass PointerHolderClass;
1.617 +
1.618 +template<typename Op>
1.619 +JSObject *
1.620 +GeneratePropertyOp(JSContext *cx, JS::HandleObject obj, JS::HandleId id, unsigned argc, Op pop)
1.621 +{
1.622 + // The JS engine provides two reserved slots on function objects for
1.623 + // XPConnect to use. Use them to stick the necessary info here.
1.624 + JSFunction *fun =
1.625 + js::NewFunctionByIdWithReserved(cx, PropertyOpForwarder<Op>, argc, 0, obj, id);
1.626 + if (!fun)
1.627 + return nullptr;
1.628 +
1.629 + JS::RootedObject funobj(cx, JS_GetFunctionObject(fun));
1.630 +
1.631 + // Unfortunately, we cannot guarantee that Op is aligned. Use a
1.632 + // second object to work around this.
1.633 + JSObject *ptrobj = JS_NewObject(cx, &PointerHolderClass, JS::NullPtr(), funobj);
1.634 + if (!ptrobj)
1.635 + return nullptr;
1.636 + Op *popp = new Op;
1.637 + if (!popp)
1.638 + return nullptr;
1.639 + *popp = pop;
1.640 + JS_SetPrivate(ptrobj, popp);
1.641 +
1.642 + js::SetFunctionNativeReserved(funobj, 0, OBJECT_TO_JSVAL(ptrobj));
1.643 + js::SetFunctionNativeReserved(funobj, 1, js::IdToValue(id));
1.644 + return funobj;
1.645 +}
1.646 +
1.647 +#endif /* xpcquickstubs_h___ */
