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gecko-dev/js/src/jsobj.cpp

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/* -*- 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/. */
/*
* JS object implementation.
*/
#include "jsobjinlines.h"
#include "mozilla/ArrayUtils.h"
#include "mozilla/MathAlgorithms.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/TemplateLib.h"
#include <string.h>
#include "jsapi.h"
#include "jsarray.h"
#include "jsatom.h"
#include "jscntxt.h"
#include "jsfriendapi.h"
#include "jsfun.h"
#include "jsgc.h"
#include "jsiter.h"
#include "jsnum.h"
#include "jsopcode.h"
#include "jsprf.h"
#include "jsproxy.h"
#include "jsscript.h"
#include "jsstr.h"
#include "jstypes.h"
#include "jsutil.h"
#include "jswatchpoint.h"
#include "jswrapper.h"
#include "builtin/Object.h"
#include "frontend/BytecodeCompiler.h"
#include "gc/Marking.h"
#include "jit/AsmJSModule.h"
#include "jit/BaselineJIT.h"
#include "js/MemoryMetrics.h"
#include "js/OldDebugAPI.h"
#include "vm/ArgumentsObject.h"
#include "vm/Interpreter.h"
#include "vm/ProxyObject.h"
#include "vm/RegExpStaticsObject.h"
#include "vm/Shape.h"
#include "jsatominlines.h"
#include "jsboolinlines.h"
#include "jscntxtinlines.h"
#include "jscompartmentinlines.h"
#include "vm/ArrayObject-inl.h"
#include "vm/BooleanObject-inl.h"
#include "vm/NumberObject-inl.h"
#include "vm/ObjectImpl-inl.h"
#include "vm/Runtime-inl.h"
#include "vm/Shape-inl.h"
#include "vm/StringObject-inl.h"
using namespace js;
using namespace js::gc;
using namespace js::types;
using js::frontend::IsIdentifier;
using mozilla::ArrayLength;
using mozilla::DebugOnly;
using mozilla::Maybe;
using mozilla::RoundUpPow2;
JS_STATIC_ASSERT(int32_t((JSObject::NELEMENTS_LIMIT - 1) * sizeof(Value)) == int64_t((JSObject::NELEMENTS_LIMIT - 1) * sizeof(Value)));
const Class JSObject::class_ = {
js_Object_str,
JSCLASS_HAS_CACHED_PROTO(JSProto_Object),
JS_PropertyStub, /* addProperty */
JS_DeletePropertyStub, /* delProperty */
JS_PropertyStub, /* getProperty */
JS_StrictPropertyStub, /* setProperty */
JS_EnumerateStub,
JS_ResolveStub,
JS_ConvertStub
};
const Class* const js::ObjectClassPtr = &JSObject::class_;
JS_FRIEND_API(JSObject *)
JS_ObjectToInnerObject(JSContext *cx, JSObject *objArg)
{
RootedObject obj(cx, objArg);
if (!obj) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_INACTIVE);
return nullptr;
}
return GetInnerObject(cx, obj);
}
JS_FRIEND_API(JSObject *)
JS_ObjectToOuterObject(JSContext *cx, JSObject *obj_)
{
Rooted<JSObject*> obj(cx, obj_);
assertSameCompartment(cx, obj);
return GetOuterObject(cx, obj);
}
JSObject *
js::NonNullObject(JSContext *cx, const Value &v)
{
if (v.isPrimitive()) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_NOT_NONNULL_OBJECT);
return nullptr;
}
return &v.toObject();
}
const char *
js::InformalValueTypeName(const Value &v)
{
if (v.isObject())
return v.toObject().getClass()->name;
if (v.isString())
return "string";
if (v.isNumber())
return "number";
if (v.isBoolean())
return "boolean";
if (v.isNull())
return "null";
if (v.isUndefined())
return "undefined";
return "value";
}
bool
js::NewPropertyDescriptorObject(JSContext *cx, Handle<PropertyDescriptor> desc,
MutableHandleValue vp)
{
if (!desc.object()) {
vp.setUndefined();
return true;
}
/* We have our own property, so start creating the descriptor. */
AutoPropDescRooter d(cx);
d.initFromPropertyDescriptor(desc);
if (!d.makeObject(cx))
return false;
vp.set(d.pd());
return true;
}
void
PropDesc::initFromPropertyDescriptor(Handle<PropertyDescriptor> desc)
{
isUndefined_ = false;
pd_.setUndefined();
attrs = uint8_t(desc.attributes());
JS_ASSERT_IF(attrs & JSPROP_READONLY, !(attrs & (JSPROP_GETTER | JSPROP_SETTER)));
if (desc.hasGetterOrSetterObject()) {
hasGet_ = true;
get_ = desc.hasGetterObject() && desc.getterObject()
? ObjectValue(*desc.getterObject())
: UndefinedValue();
hasSet_ = true;
set_ = desc.hasSetterObject() && desc.setterObject()
? ObjectValue(*desc.setterObject())
: UndefinedValue();
hasValue_ = false;
value_.setUndefined();
hasWritable_ = false;
} else {
hasGet_ = false;
get_.setUndefined();
hasSet_ = false;
set_.setUndefined();
hasValue_ = true;
value_ = desc.value();
hasWritable_ = true;
}
hasEnumerable_ = true;
hasConfigurable_ = true;
}
bool
PropDesc::makeObject(JSContext *cx)
{
MOZ_ASSERT(!isUndefined());
RootedObject obj(cx, NewBuiltinClassInstance(cx, &JSObject::class_));
if (!obj)
return false;
const JSAtomState &names = cx->names();
RootedValue configurableVal(cx, BooleanValue((attrs & JSPROP_PERMANENT) == 0));
RootedValue enumerableVal(cx, BooleanValue((attrs & JSPROP_ENUMERATE) != 0));
RootedValue writableVal(cx, BooleanValue((attrs & JSPROP_READONLY) == 0));
if ((hasConfigurable() &&
!JSObject::defineProperty(cx, obj, names.configurable, configurableVal)) ||
(hasEnumerable() &&
!JSObject::defineProperty(cx, obj, names.enumerable, enumerableVal)) ||
(hasGet() &&
!JSObject::defineProperty(cx, obj, names.get, getterValue())) ||
(hasSet() &&
!JSObject::defineProperty(cx, obj, names.set, setterValue())) ||
(hasValue() &&
!JSObject::defineProperty(cx, obj, names.value, value())) ||
(hasWritable() &&
!JSObject::defineProperty(cx, obj, names.writable, writableVal)))
{
return false;
}
pd_.setObject(*obj);
return true;
}
bool
js::GetOwnPropertyDescriptor(JSContext *cx, HandleObject obj, HandleId id,
MutableHandle<PropertyDescriptor> desc)
{
// FIXME: Call TrapGetOwnProperty directly once ScriptedIndirectProxies is removed
if (obj->is<ProxyObject>())
return Proxy::getOwnPropertyDescriptor(cx, obj, id, desc, 0);
RootedObject pobj(cx);
RootedShape shape(cx);
if (!HasOwnProperty<CanGC>(cx, obj->getOps()->lookupGeneric, obj, id, &pobj, &shape))
return false;
if (!shape) {
desc.object().set(nullptr);
return true;
}
bool doGet = true;
if (pobj->isNative()) {
desc.setAttributes(GetShapeAttributes(shape));
if (desc.hasGetterOrSetterObject()) {
doGet = false;
if (desc.hasGetterObject())
desc.setGetterObject(shape->getterObject());
if (desc.hasSetterObject())
desc.setSetterObject(shape->setterObject());
}
} else {
if (!JSObject::getGenericAttributes(cx, pobj, id, &desc.attributesRef()))
return false;
}
RootedValue value(cx);
if (doGet && !JSObject::getGeneric(cx, obj, obj, id, &value))
return false;
desc.value().set(value);
desc.object().set(obj);
return true;
}
bool
js::GetOwnPropertyDescriptor(JSContext *cx, HandleObject obj, HandleId id, MutableHandleValue vp)
{
Rooted<PropertyDescriptor> desc(cx);
return GetOwnPropertyDescriptor(cx, obj, id, &desc) &&
NewPropertyDescriptorObject(cx, desc, vp);
}
bool
js::GetFirstArgumentAsObject(JSContext *cx, const CallArgs &args, const char *method,
MutableHandleObject objp)
{
if (args.length() == 0) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_MORE_ARGS_NEEDED,
method, "0", "s");
return false;
}
HandleValue v = args[0];
if (!v.isObject()) {
char *bytes = DecompileValueGenerator(cx, JSDVG_SEARCH_STACK, v, NullPtr());
if (!bytes)
return false;
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_UNEXPECTED_TYPE,
bytes, "not an object");
js_free(bytes);
return false;
}
objp.set(&v.toObject());
return true;
}
static bool
HasProperty(JSContext *cx, HandleObject obj, HandleId id, MutableHandleValue vp, bool *foundp)
{
if (!JSObject::hasProperty(cx, obj, id, foundp, 0))
return false;
if (!*foundp) {
vp.setUndefined();
return true;
}
/*
* We must go through the method read barrier in case id is 'get' or 'set'.
* There is no obvious way to defer cloning a joined function object whose
* identity will be used by DefinePropertyOnObject, e.g., or reflected via
* js::GetOwnPropertyDescriptor, as the getter or setter callable object.
*/
return !!JSObject::getGeneric(cx, obj, obj, id, vp);
}
bool
PropDesc::initialize(JSContext *cx, const Value &origval, bool checkAccessors)
{
RootedValue v(cx, origval);
/* 8.10.5 step 1 */
if (v.isPrimitive()) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_NOT_NONNULL_OBJECT);
return false;
}
RootedObject desc(cx, &v.toObject());
/* Make a copy of the descriptor. We might need it later. */
pd_ = v;
isUndefined_ = false;
/*
* Start with the proper defaults. XXX shouldn't be necessary when we get
* rid of PropDesc::attributes()
*/
attrs = JSPROP_PERMANENT | JSPROP_READONLY;
bool found = false;
RootedId id(cx);
/* 8.10.5 step 3 */
id = NameToId(cx->names().enumerable);
if (!HasProperty(cx, desc, id, &v, &found))
return false;
if (found) {
hasEnumerable_ = true;
if (ToBoolean(v))
attrs |= JSPROP_ENUMERATE;
}
/* 8.10.5 step 4 */
id = NameToId(cx->names().configurable);
if (!HasProperty(cx, desc, id, &v, &found))
return false;
if (found) {
hasConfigurable_ = true;
if (ToBoolean(v))
attrs &= ~JSPROP_PERMANENT;
}
/* 8.10.5 step 5 */
id = NameToId(cx->names().value);
if (!HasProperty(cx, desc, id, &v, &found))
return false;
if (found) {
hasValue_ = true;
value_ = v;
}
/* 8.10.6 step 6 */
id = NameToId(cx->names().writable);
if (!HasProperty(cx, desc, id, &v, &found))
return false;
if (found) {
hasWritable_ = true;
if (ToBoolean(v))
attrs &= ~JSPROP_READONLY;
}
/* 8.10.7 step 7 */
id = NameToId(cx->names().get);
if (!HasProperty(cx, desc, id, &v, &found))
return false;
if (found) {
hasGet_ = true;
get_ = v;
attrs |= JSPROP_GETTER | JSPROP_SHARED;
attrs &= ~JSPROP_READONLY;
if (checkAccessors && !checkGetter(cx))
return false;
}
/* 8.10.7 step 8 */
id = NameToId(cx->names().set);
if (!HasProperty(cx, desc, id, &v, &found))
return false;
if (found) {
hasSet_ = true;
set_ = v;
attrs |= JSPROP_SETTER | JSPROP_SHARED;
attrs &= ~JSPROP_READONLY;
if (checkAccessors && !checkSetter(cx))
return false;
}
/* 8.10.7 step 9 */
if ((hasGet() || hasSet()) && (hasValue() || hasWritable())) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_INVALID_DESCRIPTOR);
return false;
}
JS_ASSERT_IF(attrs & JSPROP_READONLY, !(attrs & (JSPROP_GETTER | JSPROP_SETTER)));
return true;
}
void
PropDesc::complete()
{
if (isGenericDescriptor() || isDataDescriptor()) {
if (!hasValue_) {
hasValue_ = true;
value_.setUndefined();
}
if (!hasWritable_) {
hasWritable_ = true;
attrs |= JSPROP_READONLY;
}
} else {
if (!hasGet_) {
hasGet_ = true;
get_.setUndefined();
}
if (!hasSet_) {
hasSet_ = true;
set_.setUndefined();
}
}
if (!hasEnumerable_) {
hasEnumerable_ = true;
attrs &= ~JSPROP_ENUMERATE;
}
if (!hasConfigurable_) {
hasConfigurable_ = true;
attrs |= JSPROP_PERMANENT;
}
}
bool
js::Throw(JSContext *cx, jsid id, unsigned errorNumber)
{
JS_ASSERT(js_ErrorFormatString[errorNumber].argCount == 1);
JSString *idstr = IdToString(cx, id);
if (!idstr)
return false;
JSAutoByteString bytes(cx, idstr);
if (!bytes)
return false;
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, errorNumber, bytes.ptr());
return false;
}
bool
js::Throw(JSContext *cx, JSObject *obj, unsigned errorNumber)
{
if (js_ErrorFormatString[errorNumber].argCount == 1) {
RootedValue val(cx, ObjectValue(*obj));
js_ReportValueErrorFlags(cx, JSREPORT_ERROR, errorNumber,
JSDVG_IGNORE_STACK, val, NullPtr(),
nullptr, nullptr);
} else {
JS_ASSERT(js_ErrorFormatString[errorNumber].argCount == 0);
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, errorNumber);
}
return false;
}
static bool
Reject(JSContext *cx, unsigned errorNumber, bool throwError, jsid id, bool *rval)
{
if (throwError)
return Throw(cx, id, errorNumber);
*rval = false;
return true;
}
static bool
Reject(JSContext *cx, JSObject *obj, unsigned errorNumber, bool throwError, bool *rval)
{
if (throwError)
return Throw(cx, obj, errorNumber);
*rval = false;
return true;
}
static bool
Reject(JSContext *cx, HandleId id, unsigned errorNumber, bool throwError, bool *rval)
{
if (throwError)
return Throw(cx, id, errorNumber);
*rval = false;
return true;
}
// See comments on CheckDefineProperty in jsobj.h.
//
// DefinePropertyOnObject has its own implementation of these checks.
//
JS_FRIEND_API(bool)
js::CheckDefineProperty(JSContext *cx, HandleObject obj, HandleId id, HandleValue value,
PropertyOp getter, StrictPropertyOp setter, unsigned attrs)
{
if (!obj->isNative())
return true;
// ES5 8.12.9 Step 1. Even though we know obj is native, we use generic
// APIs for shorter, more readable code.
Rooted<PropertyDescriptor> desc(cx);
if (!GetOwnPropertyDescriptor(cx, obj, id, &desc))
return false;
// This does not have to check obj's extensibility when !desc.obj (steps
// 2-3) because the low-level methods JSObject::{add,put}Property check
// for that.
if (desc.object() && desc.isPermanent()) {
// Steps 6-11, skipping step 10.a.ii. Prohibit redefining a permanent
// property with different metadata, except to make a writable property
// non-writable.
if (getter != desc.getter() ||
setter != desc.setter() ||
(attrs != desc.attributes() && attrs != (desc.attributes() | JSPROP_READONLY)))
{
return Throw(cx, id, JSMSG_CANT_REDEFINE_PROP);
}
// Step 10.a.ii. Prohibit changing the value of a non-configurable,
// non-writable data property.
if ((desc.attributes() & (JSPROP_GETTER | JSPROP_SETTER | JSPROP_READONLY)) == JSPROP_READONLY) {
bool same;
if (!SameValue(cx, value, desc.value(), &same))
return false;
if (!same)
return JSObject::reportReadOnly(cx, id);
}
}
return true;
}
static bool
DefinePropertyOnObject(JSContext *cx, HandleObject obj, HandleId id, const PropDesc &desc,
bool throwError, bool *rval)
{
/* 8.12.9 step 1. */
RootedShape shape(cx);
RootedObject obj2(cx);
JS_ASSERT(!obj->getOps()->lookupGeneric);
if (!HasOwnProperty<CanGC>(cx, nullptr, obj, id, &obj2, &shape))
return false;
JS_ASSERT(!obj->getOps()->defineProperty);
/* 8.12.9 steps 2-4. */
if (!shape) {
bool extensible;
if (!JSObject::isExtensible(cx, obj, &extensible))
return false;
if (!extensible)
return Reject(cx, obj, JSMSG_OBJECT_NOT_EXTENSIBLE, throwError, rval);
*rval = true;
if (desc.isGenericDescriptor() || desc.isDataDescriptor()) {
JS_ASSERT(!obj->getOps()->defineProperty);
RootedValue v(cx, desc.hasValue() ? desc.value() : UndefinedValue());
return baseops::DefineGeneric(cx, obj, id, v,
JS_PropertyStub, JS_StrictPropertyStub,
desc.attributes());
}
JS_ASSERT(desc.isAccessorDescriptor());
/*
* Getters and setters are just like watchpoints from an access
* control point of view.
*/
RootedValue dummy(cx);
unsigned dummyAttrs;
if (!CheckAccess(cx, obj, id, JSACC_WATCH, &dummy, &dummyAttrs))
return false;
RootedValue tmp(cx, UndefinedValue());
return baseops::DefineGeneric(cx, obj, id, tmp,
desc.getter(), desc.setter(), desc.attributes());
}
/* 8.12.9 steps 5-6 (note 5 is merely a special case of 6). */
RootedValue v(cx, UndefinedValue());
JS_ASSERT(obj == obj2);
bool shapeDataDescriptor = true,
shapeAccessorDescriptor = false,
shapeWritable = true,
shapeConfigurable = true,
shapeEnumerable = true,
shapeHasDefaultGetter = true,
shapeHasDefaultSetter = true,
shapeHasGetterValue = false,
shapeHasSetterValue = false;
uint8_t shapeAttributes = JSPROP_ENUMERATE;
if (!IsImplicitDenseElement(shape)) {
shapeDataDescriptor = shape->isDataDescriptor();
shapeAccessorDescriptor = shape->isAccessorDescriptor();
shapeWritable = shape->writable();
shapeConfigurable = shape->configurable();
shapeEnumerable = shape->enumerable();
shapeHasDefaultGetter = shape->hasDefaultGetter();
shapeHasDefaultSetter = shape->hasDefaultSetter();
shapeHasGetterValue = shape->hasGetterValue();
shapeHasSetterValue = shape->hasSetterValue();
shapeAttributes = shape->attributes();
}
do {
if (desc.isAccessorDescriptor()) {
if (!shapeAccessorDescriptor)
break;
if (desc.hasGet()) {
bool same;
if (!SameValue(cx, desc.getterValue(), shape->getterOrUndefined(), &same))
return false;
if (!same)
break;
}
if (desc.hasSet()) {
bool same;
if (!SameValue(cx, desc.setterValue(), shape->setterOrUndefined(), &same))
return false;
if (!same)
break;
}
} else {
/*
* Determine the current value of the property once, if the current
* value might actually need to be used or preserved later. NB: we
* guard on whether the current property is a data descriptor to
* avoid calling a getter; we won't need the value if it's not a
* data descriptor.
*/
if (IsImplicitDenseElement(shape)) {
v = obj->getDenseElement(JSID_TO_INT(id));
} else if (shape->isDataDescriptor()) {
/*
* We must rule out a non-configurable js::PropertyOp-guarded
* property becoming a writable unguarded data property, since
* such a property can have its value changed to one the getter
* and setter preclude.
*
* A desc lacking writable but with value is a data descriptor
* and we must reject it as if it had writable: true if current
* is writable.
*/
if (!shape->configurable() &&
(!shape->hasDefaultGetter() || !shape->hasDefaultSetter()) &&
desc.isDataDescriptor() &&
(desc.hasWritable() ? desc.writable() : shape->writable()))
{
return Reject(cx, JSMSG_CANT_REDEFINE_PROP, throwError, id, rval);
}
if (!NativeGet(cx, obj, obj2, shape, &v))
return false;
}
if (desc.isDataDescriptor()) {
if (!shapeDataDescriptor)
break;
bool same;
if (desc.hasValue()) {
if (!SameValue(cx, desc.value(), v, &same))
return false;
if (!same) {
/*
* Insist that a non-configurable js::PropertyOp data
* property is frozen at exactly the last-got value.
*
* Duplicate the first part of the big conjunction that
* we tested above, rather than add a local bool flag.
* Likewise, don't try to keep shape->writable() in a
* flag we veto from true to false for non-configurable
* PropertyOp-based data properties and test before the
* SameValue check later on in order to re-use that "if
* (!SameValue) Reject" logic.
*
* This function is large and complex enough that it
* seems best to repeat a small bit of code and return
* Reject(...) ASAP, instead of being clever.
*/
if (!shapeConfigurable &&
(!shape->hasDefaultGetter() || !shape->hasDefaultSetter()))
{
return Reject(cx, JSMSG_CANT_REDEFINE_PROP, throwError, id, rval);
}
break;
}
}
if (desc.hasWritable() && desc.writable() != shapeWritable)
break;
} else {
/* The only fields in desc will be handled below. */
JS_ASSERT(desc.isGenericDescriptor());
}
}
if (desc.hasConfigurable() && desc.configurable() != shapeConfigurable)
break;
if (desc.hasEnumerable() && desc.enumerable() != shapeEnumerable)
break;
/* The conditions imposed by step 5 or step 6 apply. */
*rval = true;
return true;
} while (0);
/* 8.12.9 step 7. */
if (!shapeConfigurable) {
if ((desc.hasConfigurable() && desc.configurable()) ||
(desc.hasEnumerable() && desc.enumerable() != shape->enumerable())) {
return Reject(cx, JSMSG_CANT_REDEFINE_PROP, throwError, id, rval);
}
}
bool callDelProperty = false;
if (desc.isGenericDescriptor()) {
/* 8.12.9 step 8, no validation required */
} else if (desc.isDataDescriptor() != shapeDataDescriptor) {
/* 8.12.9 step 9. */
if (!shapeConfigurable)
return Reject(cx, JSMSG_CANT_REDEFINE_PROP, throwError, id, rval);
} else if (desc.isDataDescriptor()) {
/* 8.12.9 step 10. */
JS_ASSERT(shapeDataDescriptor);
if (!shapeConfigurable && !shape->writable()) {
if (desc.hasWritable() && desc.writable())
return Reject(cx, JSMSG_CANT_REDEFINE_PROP, throwError, id, rval);
if (desc.hasValue()) {
bool same;
if (!SameValue(cx, desc.value(), v, &same))
return false;
if (!same)
return Reject(cx, JSMSG_CANT_REDEFINE_PROP, throwError, id, rval);
}
}
callDelProperty = !shapeHasDefaultGetter || !shapeHasDefaultSetter;
} else {
/* 8.12.9 step 11. */
JS_ASSERT(desc.isAccessorDescriptor() && shape->isAccessorDescriptor());
if (!shape->configurable()) {
if (desc.hasSet()) {
bool same;
if (!SameValue(cx, desc.setterValue(), shape->setterOrUndefined(), &same))
return false;
if (!same)
return Reject(cx, JSMSG_CANT_REDEFINE_PROP, throwError, id, rval);
}
if (desc.hasGet()) {
bool same;
if (!SameValue(cx, desc.getterValue(), shape->getterOrUndefined(), &same))
return false;
if (!same)
return Reject(cx, JSMSG_CANT_REDEFINE_PROP, throwError, id, rval);
}
}
}
/* 8.12.9 step 12. */
unsigned attrs;
PropertyOp getter;
StrictPropertyOp setter;
if (desc.isGenericDescriptor()) {
unsigned changed = 0;
if (desc.hasConfigurable())
changed |= JSPROP_PERMANENT;
if (desc.hasEnumerable())
changed |= JSPROP_ENUMERATE;
attrs = (shapeAttributes & ~changed) | (desc.attributes() & changed);
getter = IsImplicitDenseElement(shape) ? JS_PropertyStub : shape->getter();
setter = IsImplicitDenseElement(shape) ? JS_StrictPropertyStub : shape->setter();
} else if (desc.isDataDescriptor()) {
unsigned unchanged = 0;
if (!desc.hasConfigurable())
unchanged |= JSPROP_PERMANENT;
if (!desc.hasEnumerable())
unchanged |= JSPROP_ENUMERATE;
/* Watch out for accessor -> data transformations here. */
if (!desc.hasWritable() && shapeDataDescriptor)
unchanged |= JSPROP_READONLY;
if (desc.hasValue())
v = desc.value();
attrs = (desc.attributes() & ~unchanged) | (shapeAttributes & unchanged);
getter = JS_PropertyStub;
setter = JS_StrictPropertyStub;
} else {
JS_ASSERT(desc.isAccessorDescriptor());
/*
* Getters and setters are just like watchpoints from an access
* control point of view.
*/
RootedValue dummy(cx);
if (!CheckAccess(cx, obj2, id, JSACC_WATCH, &dummy, &attrs))
return false;
/* 8.12.9 step 12. */
unsigned changed = 0;
if (desc.hasConfigurable())
changed |= JSPROP_PERMANENT;
if (desc.hasEnumerable())
changed |= JSPROP_ENUMERATE;
if (desc.hasGet())
changed |= JSPROP_GETTER | JSPROP_SHARED | JSPROP_READONLY;
if (desc.hasSet())
changed |= JSPROP_SETTER | JSPROP_SHARED | JSPROP_READONLY;
attrs = (desc.attributes() & changed) | (shapeAttributes & ~changed);
if (desc.hasGet()) {
getter = desc.getter();
} else {
getter = (shapeHasDefaultGetter && !shapeHasGetterValue)
? JS_PropertyStub
: shape->getter();
}
if (desc.hasSet()) {
setter = desc.setter();
} else {
setter = (shapeHasDefaultSetter && !shapeHasSetterValue)
? JS_StrictPropertyStub
: shape->setter();
}
}
*rval = true;
/*
* Since "data" properties implemented using native C functions may rely on
* side effects during setting, we must make them aware that they have been
* "assigned"; deleting the property before redefining it does the trick.
* See bug 539766, where we ran into problems when we redefined
* arguments.length without making the property aware that its value had
* been changed (which would have happened if we had deleted it before
* redefining it or we had invoked its setter to change its value).
*/
if (callDelProperty) {
bool succeeded;
if (!CallJSDeletePropertyOp(cx, obj2->getClass()->delProperty, obj2, id, &succeeded))
return false;
}
return baseops::DefineGeneric(cx, obj, id, v, getter, setter, attrs);
}
/* ES6 20130308 draft 8.4.2.1 [[DefineOwnProperty]] */
static bool
DefinePropertyOnArray(JSContext *cx, Handle<ArrayObject*> arr, HandleId id, const PropDesc &desc,
bool throwError, bool *rval)
{
/* Step 2. */
if (id == NameToId(cx->names().length)) {
// Canonicalize value, if necessary, before proceeding any further. It
// would be better if this were always/only done by ArraySetLength.
// But canonicalization may throw a RangeError (or other exception, if
// the value is an object with user-defined conversion semantics)
// before other attributes are checked. So as long as our internal
// defineProperty hook doesn't match the ECMA one, this duplicate
// checking can't be helped.
RootedValue v(cx);
if (desc.hasValue()) {
uint32_t newLen;
if (!CanonicalizeArrayLengthValue<SequentialExecution>(cx, desc.value(), &newLen))
return false;
v.setNumber(newLen);
} else {
v.setNumber(arr->length());
}
if (desc.hasConfigurable() && desc.configurable())
return Reject(cx, id, JSMSG_CANT_REDEFINE_PROP, throwError, rval);
if (desc.hasEnumerable() && desc.enumerable())
return Reject(cx, id, JSMSG_CANT_REDEFINE_PROP, throwError, rval);
if (desc.isAccessorDescriptor())
return Reject(cx, id, JSMSG_CANT_REDEFINE_PROP, throwError, rval);
unsigned attrs = arr->nativeLookup(cx, id)->attributes();
if (!arr->lengthIsWritable()) {
if (desc.hasWritable() && desc.writable())
return Reject(cx, id, JSMSG_CANT_REDEFINE_PROP, throwError, rval);
} else {
if (desc.hasWritable() && !desc.writable())
attrs = attrs | JSPROP_READONLY;
}
return ArraySetLength<SequentialExecution>(cx, arr, id, attrs, v, throwError);
}
/* Step 3. */
uint32_t index;
if (js_IdIsIndex(id, &index)) {
/* Step 3b. */
uint32_t oldLen = arr->length();
/* Steps 3a, 3e. */
if (index >= oldLen && !arr->lengthIsWritable())
return Reject(cx, arr, JSMSG_CANT_APPEND_TO_ARRAY, throwError, rval);
/* Steps 3f-j. */
return DefinePropertyOnObject(cx, arr, id, desc, throwError, rval);
}
/* Step 4. */
return DefinePropertyOnObject(cx, arr, id, desc, throwError, rval);
}
bool
js::DefineProperty(JSContext *cx, HandleObject obj, HandleId id, const PropDesc &desc,
bool throwError, bool *rval)
{
if (obj->is<ArrayObject>()) {
Rooted<ArrayObject*> arr(cx, &obj->as<ArrayObject>());
return DefinePropertyOnArray(cx, arr, id, desc, throwError, rval);
}
if (obj->getOps()->lookupGeneric) {
/*
* FIXME: Once ScriptedIndirectProxies are removed, this code should call
* TrapDefineOwnProperty directly
*/
if (obj->is<ProxyObject>()) {
RootedValue pd(cx, desc.pd());
return Proxy::defineProperty(cx, obj, id, pd);
}
return Reject(cx, obj, JSMSG_OBJECT_NOT_EXTENSIBLE, throwError, rval);
}
return DefinePropertyOnObject(cx, obj, id, desc, throwError, rval);
}
bool
js::DefineOwnProperty(JSContext *cx, HandleObject obj, HandleId id, HandleValue descriptor,
bool *bp)
{
AutoPropDescArrayRooter descs(cx);
PropDesc *desc = descs.append();
if (!desc || !desc->initialize(cx, descriptor))
return false;
bool rval;
if (!DefineProperty(cx, obj, id, *desc, true, &rval))
return false;
*bp = !!rval;
return true;
}
bool
js::DefineOwnProperty(JSContext *cx, HandleObject obj, HandleId id,
Handle<PropertyDescriptor> descriptor, bool *bp)
{
AutoPropDescArrayRooter descs(cx);
PropDesc *desc = descs.append();
if (!desc)
return false;
desc->initFromPropertyDescriptor(descriptor);
bool rval;
if (!DefineProperty(cx, obj, id, *desc, true, &rval))
return false;
*bp = !!rval;
return true;
}
bool
js::ReadPropertyDescriptors(JSContext *cx, HandleObject props, bool checkAccessors,
AutoIdVector *ids, AutoPropDescArrayRooter *descs)
{
if (!GetPropertyNames(cx, props, JSITER_OWNONLY, ids))
return false;
RootedId id(cx);
for (size_t i = 0, len = ids->length(); i < len; i++) {
id = (*ids)[i];
PropDesc* desc = descs->append();
RootedValue v(cx);
if (!desc ||
!JSObject::getGeneric(cx, props, props, id, &v) ||
!desc->initialize(cx, v, checkAccessors))
{
return false;
}
}
return true;
}
bool
js::DefineProperties(JSContext *cx, HandleObject obj, HandleObject props)
{
AutoIdVector ids(cx);
AutoPropDescArrayRooter descs(cx);
if (!ReadPropertyDescriptors(cx, props, true, &ids, &descs))
return false;
if (obj->is<ArrayObject>()) {
bool dummy;
Rooted<ArrayObject*> arr(cx, &obj->as<ArrayObject>());
for (size_t i = 0, len = ids.length(); i < len; i++) {
if (!DefinePropertyOnArray(cx, arr, ids.handleAt(i), descs[i], true, &dummy))
return false;
}
return true;
}
if (obj->getOps()->lookupGeneric) {
/*
* FIXME: Once ScriptedIndirectProxies are removed, this code should call
* TrapDefineOwnProperty directly
*/
if (obj->is<ProxyObject>()) {
for (size_t i = 0, len = ids.length(); i < len; i++) {
RootedValue pd(cx, descs[i].pd());
if (!Proxy::defineProperty(cx, obj, ids.handleAt(i), pd))
return false;
}
return true;
}
bool dummy;
return Reject(cx, obj, JSMSG_OBJECT_NOT_EXTENSIBLE, true, &dummy);
}
bool dummy;
for (size_t i = 0, len = ids.length(); i < len; i++) {
if (!DefinePropertyOnObject(cx, obj, ids.handleAt(i), descs[i], true, &dummy))
return false;
}
return true;
}
extern bool
js_PopulateObject(JSContext *cx, HandleObject newborn, HandleObject props)
{
return DefineProperties(cx, newborn, props);
}
js::types::TypeObject*
JSObject::uninlinedGetType(JSContext *cx)
{
return getType(cx);
}
void
JSObject::uninlinedSetType(js::types::TypeObject *newType)
{
setType(newType);
}
/* static */ inline unsigned
JSObject::getSealedOrFrozenAttributes(unsigned attrs, ImmutabilityType it)
{
/* Make all attributes permanent; if freezing, make data attributes read-only. */
if (it == FREEZE && !(attrs & (JSPROP_GETTER | JSPROP_SETTER)))
return JSPROP_PERMANENT | JSPROP_READONLY;
return JSPROP_PERMANENT;
}
/* static */ bool
JSObject::sealOrFreeze(JSContext *cx, HandleObject obj, ImmutabilityType it)
{
assertSameCompartment(cx, obj);
JS_ASSERT(it == SEAL || it == FREEZE);
bool extensible;
if (!JSObject::isExtensible(cx, obj, &extensible))
return false;
if (extensible && !JSObject::preventExtensions(cx, obj))
return false;
AutoIdVector props(cx);
if (!GetPropertyNames(cx, obj, JSITER_HIDDEN | JSITER_OWNONLY, &props))
return false;
/* preventExtensions must sparsify dense objects, so we can assign to holes without checks. */
JS_ASSERT_IF(obj->isNative(), obj->getDenseCapacity() == 0);
if (obj->isNative() && !obj->inDictionaryMode()) {
/*
* Seal/freeze non-dictionary objects by constructing a new shape
* hierarchy mirroring the original one, which can be shared if many
* objects with the same structure are sealed/frozen. If we use the
* generic path below then any non-empty object will be converted to
* dictionary mode.
*/
RootedShape last(cx, EmptyShape::getInitialShape(cx, obj->getClass(),
obj->getTaggedProto(),
obj->getParent(),
obj->getMetadata(),
obj->numFixedSlots(),
obj->lastProperty()->getObjectFlags()));
if (!last)
return false;
/* Get an in order list of the shapes in this object. */
AutoShapeVector shapes(cx);
for (Shape::Range<NoGC> r(obj->lastProperty()); !r.empty(); r.popFront()) {
if (!shapes.append(&r.front()))
return false;
}
Reverse(shapes.begin(), shapes.end());
for (size_t i = 0; i < shapes.length(); i++) {
StackShape child(shapes[i]);
StackShape::AutoRooter rooter(cx, &child);
child.attrs |= getSealedOrFrozenAttributes(child.attrs, it);
if (!JSID_IS_EMPTY(child.propid))
MarkTypePropertyConfigured(cx, obj, child.propid);
last = cx->compartment()->propertyTree.getChild(cx, last, obj->numFixedSlots(), child);
if (!last)
return false;
}
JS_ASSERT(obj->lastProperty()->slotSpan() == last->slotSpan());
JS_ALWAYS_TRUE(setLastProperty(cx, obj, last));
} else {
RootedId id(cx);
for (size_t i = 0; i < props.length(); i++) {
id = props[i];
unsigned attrs;
if (!getGenericAttributes(cx, obj, id, &attrs))
return false;
unsigned new_attrs = getSealedOrFrozenAttributes(attrs, it);
/* If we already have the attributes we need, skip the setAttributes call. */
if ((attrs | new_attrs) == attrs)
continue;
attrs |= new_attrs;
if (!setGenericAttributes(cx, obj, id, &attrs))
return false;
}
}
// Ordinarily ArraySetLength handles this, but we're going behind its back
// right now, so we must do this manually. Neither the custom property
// tree mutations nor the setGenericAttributes call in the above code will
// do this for us.
//
// ArraySetLength also implements the capacity <= length invariant for
// arrays with non-writable length. We don't need to do anything special
// for that, because capacity was zeroed out by preventExtensions. (See
// the assertion before the if-else above.)
if (it == FREEZE && obj->is<ArrayObject>())
obj->getElementsHeader()->setNonwritableArrayLength();
return true;
}
/* static */ bool
JSObject::isSealedOrFrozen(JSContext *cx, HandleObject obj, ImmutabilityType it, bool *resultp)
{
bool extensible;
if (!JSObject::isExtensible(cx, obj, &extensible))
return false;
if (extensible) {
*resultp = false;
return true;
}
if (obj->is<TypedArrayObject>()) {
if (it == SEAL) {
// Typed arrays are always sealed.
*resultp = true;
} else {
// Typed arrays cannot be frozen, but an empty typed array is
// trivially frozen.
*resultp = (obj->as<TypedArrayObject>().length() == 0);
}
return true;
}
AutoIdVector props(cx);
if (!GetPropertyNames(cx, obj, JSITER_HIDDEN | JSITER_OWNONLY, &props))
return false;
RootedId id(cx);
for (size_t i = 0, len = props.length(); i < len; i++) {
id = props[i];
unsigned attrs;
if (!getGenericAttributes(cx, obj, id, &attrs))
return false;
/*
* If the property is configurable, this object is neither sealed nor
* frozen. If the property is a writable data property, this object is
* not frozen.
*/
if (!(attrs & JSPROP_PERMANENT) ||
(it == FREEZE && !(attrs & (JSPROP_READONLY | JSPROP_GETTER | JSPROP_SETTER))))
{
*resultp = false;
return true;
}
}
/* All properties checked out. This object is sealed/frozen. */
*resultp = true;
return true;
}
/* static */
const char *
JSObject::className(JSContext *cx, HandleObject obj)
{
assertSameCompartment(cx, obj);
if (obj->is<ProxyObject>())
return Proxy::className(cx, obj);
return obj->getClass()->name;
}
/*
* Get the GC kind to use for scripted 'new' on the given class.
* FIXME bug 547327: estimate the size from the allocation site.
*/
static inline gc::AllocKind
NewObjectGCKind(const js::Class *clasp)
{
if (clasp == &ArrayObject::class_)
return gc::FINALIZE_OBJECT8;
if (clasp == &JSFunction::class_)
return gc::FINALIZE_OBJECT2;
return gc::FINALIZE_OBJECT4;
}
static inline JSObject *
NewObject(ExclusiveContext *cx, const Class *clasp, types::TypeObject *type_, JSObject *parent,
gc::AllocKind kind, NewObjectKind newKind)
{
JS_ASSERT(clasp != &ArrayObject::class_);
JS_ASSERT_IF(clasp == &JSFunction::class_,
kind == JSFunction::FinalizeKind || kind == JSFunction::ExtendedFinalizeKind);
JS_ASSERT_IF(parent, &parent->global() == cx->global());
RootedTypeObject type(cx, type_);
JSObject *metadata = nullptr;
if (!NewObjectMetadata(cx, &metadata))
return nullptr;
RootedShape shape(cx, EmptyShape::getInitialShape(cx, clasp, type->proto(),
parent, metadata, kind));
if (!shape)
return nullptr;
gc::InitialHeap heap = GetInitialHeap(newKind, clasp);
JSObject *obj = JSObject::create(cx, kind, heap, shape, type);
if (!obj)
return nullptr;
if (newKind == SingletonObject) {
RootedObject nobj(cx, obj);
if (!JSObject::setSingletonType(cx, nobj))
return nullptr;
obj = nobj;
}
/*
* This will cancel an already-running incremental GC from doing any more
* slices, and it will prevent any future incremental GCs.
*/
if (clasp->trace && !(clasp->flags & JSCLASS_IMPLEMENTS_BARRIERS)) {
if (!cx->shouldBeJSContext())
return nullptr;
JSRuntime *rt = cx->asJSContext()->runtime();
rt->gcIncrementalEnabled = false;
#ifdef DEBUG
if (rt->gcMode() == JSGC_MODE_INCREMENTAL) {
fprintf(stderr,
"The class %s has a trace hook but does not declare the\n"
"JSCLASS_IMPLEMENTS_BARRIERS flag. Please ensure that it correctly\n"
"implements write barriers and then set the flag.\n",
clasp->name);
MOZ_CRASH();
}
#endif
}
probes::CreateObject(cx, obj);
return obj;
}
void
NewObjectCache::fillProto(EntryIndex entry, const Class *clasp, js::TaggedProto proto,
gc::AllocKind kind, JSObject *obj)
{
JS_ASSERT_IF(proto.isObject(), !proto.toObject()->is<GlobalObject>());
JS_ASSERT(obj->getTaggedProto() == proto);
return fill(entry, clasp, proto.raw(), kind, obj);
}
JSObject *
js::NewObjectWithGivenProto(ExclusiveContext *cxArg, const js::Class *clasp,
js::TaggedProto proto_, JSObject *parent_,
gc::AllocKind allocKind, NewObjectKind newKind)
{
Rooted<TaggedProto> proto(cxArg, proto_);
RootedObject parent(cxArg, parent_);
if (CanBeFinalizedInBackground(allocKind, clasp))
allocKind = GetBackgroundAllocKind(allocKind);
NewObjectCache::EntryIndex entry = -1;
if (JSContext *cx = cxArg->maybeJSContext()) {
NewObjectCache &cache = cx->runtime()->newObjectCache;
if (proto.isObject() &&
newKind == GenericObject &&
!cx->compartment()->hasObjectMetadataCallback() &&
(!parent || parent == proto.toObject()->getParent()) &&
!proto.toObject()->is<GlobalObject>())
{
if (cache.lookupProto(clasp, proto.toObject(), allocKind, &entry)) {
JSObject *obj = cache.newObjectFromHit(cx, entry, GetInitialHeap(newKind, clasp));
if (obj)
return obj;
}
}
}
types::TypeObject *type = cxArg->getNewType(clasp, proto, nullptr);
if (!type)
return nullptr;
/*
* Default parent to the parent of the prototype, which was set from
* the parent of the prototype's constructor.
*/
if (!parent && proto.isObject())
parent = proto.toObject()->getParent();
RootedObject obj(cxArg, NewObject(cxArg, clasp, type, parent, allocKind, newKind));
if (!obj)
return nullptr;
if (entry != -1 && !obj->hasDynamicSlots()) {
cxArg->asJSContext()->runtime()->newObjectCache.fillProto(entry, clasp,
proto, allocKind, obj);
}
return obj;
}
JSObject *
js::NewObjectWithClassProtoCommon(ExclusiveContext *cxArg,
const js::Class *clasp, JSObject *protoArg, JSObject *parentArg,
gc::AllocKind allocKind, NewObjectKind newKind)
{
if (protoArg)
return NewObjectWithGivenProto(cxArg, clasp, protoArg, parentArg, allocKind, newKind);
if (CanBeFinalizedInBackground(allocKind, clasp))
allocKind = GetBackgroundAllocKind(allocKind);
if (!parentArg)
parentArg = cxArg->global();
/*
* Use the object cache, except for classes without a cached proto key.
* On these objects, FindProto will do a dynamic property lookup to get
* global[className].prototype, where changes to either the className or
* prototype property would render the cached lookup incorrect. For classes
* with a proto key, the prototype created during class initialization is
* stored in an immutable slot on the global (except for ClearScope, which
* will flush the new object cache).
*/
JSProtoKey protoKey = GetClassProtoKey(clasp);
NewObjectCache::EntryIndex entry = -1;
if (JSContext *cx = cxArg->maybeJSContext()) {
NewObjectCache &cache = cx->runtime()->newObjectCache;
if (parentArg->is<GlobalObject>() &&
protoKey != JSProto_Null &&
newKind == GenericObject &&
!cx->compartment()->hasObjectMetadataCallback())
{
if (cache.lookupGlobal(clasp, &parentArg->as<GlobalObject>(), allocKind, &entry)) {
JSObject *obj = cache.newObjectFromHit(cx, entry, GetInitialHeap(newKind, clasp));
if (obj)
return obj;
}
}
}
RootedObject parent(cxArg, parentArg);
RootedObject proto(cxArg, protoArg);
if (!FindProto(cxArg, clasp, &proto))
return nullptr;
types::TypeObject *type = cxArg->getNewType(clasp, proto.get());
if (!type)
return nullptr;
JSObject *obj = NewObject(cxArg, clasp, type, parent, allocKind, newKind);
if (!obj)
return nullptr;
if (entry != -1 && !obj->hasDynamicSlots()) {
cxArg->asJSContext()->runtime()->newObjectCache.fillGlobal(entry, clasp,
&parent->as<GlobalObject>(),
allocKind, obj);
}
return obj;
}
/*
* Create a plain object with the specified type. This bypasses getNewType to
* avoid losing creation site information for objects made by scripted 'new'.
*/
JSObject *
js::NewObjectWithType(JSContext *cx, HandleTypeObject type, JSObject *parent, gc::AllocKind allocKind,
NewObjectKind newKind)
{
JS_ASSERT(parent);
JS_ASSERT(allocKind <= gc::FINALIZE_OBJECT_LAST);
if (CanBeFinalizedInBackground(allocKind, &JSObject::class_))
allocKind = GetBackgroundAllocKind(allocKind);
NewObjectCache &cache = cx->runtime()->newObjectCache;
NewObjectCache::EntryIndex entry = -1;
if (parent == type->proto().toObject()->getParent() &&
newKind == GenericObject &&
!cx->compartment()->hasObjectMetadataCallback())
{
if (cache.lookupType(&JSObject::class_, type, allocKind, &entry)) {
JSObject *obj = cache.newObjectFromHit(cx, entry, GetInitialHeap(newKind, &JSObject::class_));
if (obj)
return obj;
}
}
JSObject *obj = NewObject(cx, &JSObject::class_, type, parent, allocKind, newKind);
if (!obj)
return nullptr;
if (entry != -1 && !obj->hasDynamicSlots())
cache.fillType(entry, &JSObject::class_, type, allocKind, obj);
return obj;
}
bool
js::NewObjectScriptedCall(JSContext *cx, MutableHandleObject pobj)
{
jsbytecode *pc;
RootedScript script(cx, cx->currentScript(&pc));
gc::AllocKind allocKind = NewObjectGCKind(&JSObject::class_);
NewObjectKind newKind = script
? UseNewTypeForInitializer(script, pc, &JSObject::class_)
: GenericObject;
RootedObject obj(cx, NewBuiltinClassInstance(cx, &JSObject::class_, allocKind, newKind));
if (!obj)
return false;
if (script) {
/* Try to specialize the type of the object to the scripted call site. */
if (!types::SetInitializerObjectType(cx, script, pc, obj, newKind))
return false;
}
pobj.set(obj);
return true;
}
JSObject*
js::CreateThis(JSContext *cx, const Class *newclasp, HandleObject callee)
{
RootedValue protov(cx);
if (!JSObject::getProperty(cx, callee, callee, cx->names().prototype, &protov))
return nullptr;
JSObject *proto = protov.isObjectOrNull() ? protov.toObjectOrNull() : nullptr;
JSObject *parent = callee->getParent();
gc::AllocKind kind = NewObjectGCKind(newclasp);
return NewObjectWithClassProto(cx, newclasp, proto, parent, kind);
}
static inline JSObject *
CreateThisForFunctionWithType(JSContext *cx, HandleTypeObject type, JSObject *parent,
NewObjectKind newKind)
{
if (type->hasNewScript()) {
/*
* Make an object with the type's associated finalize kind and shape,
* which reflects any properties that will definitely be added to the
* object before it is read from.
*/
RootedObject templateObject(cx, type->newScript()->templateObject);
JS_ASSERT(templateObject->type() == type);
RootedObject res(cx, CopyInitializerObject(cx, templateObject, newKind));
if (!res)
return nullptr;
if (newKind == SingletonObject) {
Rooted<TaggedProto> proto(cx, templateObject->getProto());
if (!res->splicePrototype(cx, &JSObject::class_, proto))
return nullptr;
} else {
res->setType(type);
}
return res;
}
gc::AllocKind allocKind = NewObjectGCKind(&JSObject::class_);
return NewObjectWithType(cx, type, parent, allocKind, newKind);
}
JSObject *
js::CreateThisForFunctionWithProto(JSContext *cx, HandleObject callee, JSObject *proto,
NewObjectKind newKind /* = GenericObject */)
{
RootedObject res(cx);
if (proto) {
RootedTypeObject type(cx, cx->getNewType(&JSObject::class_, proto, &callee->as<JSFunction>()));
if (!type)
return nullptr;
res = CreateThisForFunctionWithType(cx, type, callee->getParent(), newKind);
} else {
gc::AllocKind allocKind = NewObjectGCKind(&JSObject::class_);
res = NewObjectWithClassProto(cx, &JSObject::class_, proto, callee->getParent(), allocKind, newKind);
}
if (res && cx->typeInferenceEnabled()) {
JSScript *script = callee->as<JSFunction>().getOrCreateScript(cx);
if (!script)
return nullptr;
TypeScript::SetThis(cx, script, types::Type::ObjectType(res));
}
return res;
}
JSObject *
js::CreateThisForFunction(JSContext *cx, HandleObject callee, NewObjectKind newKind)
{
RootedValue protov(cx);
if (!JSObject::getProperty(cx, callee, callee, cx->names().prototype, &protov))
return nullptr;
JSObject *proto;
if (protov.isObject())
proto = &protov.toObject();
else
proto = nullptr;
JSObject *obj = CreateThisForFunctionWithProto(cx, callee, proto, newKind);
if (obj && newKind == SingletonObject) {
RootedObject nobj(cx, obj);
/* Reshape the singleton before passing it as the 'this' value. */
JSObject::clear(cx, nobj);
JSScript *calleeScript = callee->as<JSFunction>().nonLazyScript();
TypeScript::SetThis(cx, calleeScript, types::Type::ObjectType(nobj));
return nobj;
}
return obj;
}
/*
* Given pc pointing after a property accessing bytecode, return true if the
* access is "object-detecting" in the sense used by web scripts, e.g., when
* checking whether document.all is defined.
*/
static bool
Detecting(JSContext *cx, JSScript *script, jsbytecode *pc)
{
JS_ASSERT(script->containsPC(pc));
/* General case: a branch or equality op follows the access. */
JSOp op = JSOp(*pc);
if (js_CodeSpec[op].format & JOF_DETECTING)
return true;
jsbytecode *endpc = script->codeEnd();
if (op == JSOP_NULL) {
/*
* Special case #1: handle (document.all == null). Don't sweat
* about JS1.2's revision of the equality operators here.
*/
if (++pc < endpc) {
op = JSOp(*pc);
return op == JSOP_EQ || op == JSOP_NE;
}
return false;
}
if (op == JSOP_GETGNAME || op == JSOP_NAME) {
/*
* Special case #2: handle (document.all == undefined). Don't worry
* about a local variable named |undefined| shadowing the immutable
* global binding...because, really?
*/
JSAtom *atom = script->getAtom(GET_UINT32_INDEX(pc));
if (atom == cx->names().undefined &&
(pc += js_CodeSpec[op].length) < endpc) {
op = JSOp(*pc);
return op == JSOP_EQ || op == JSOP_NE || op == JSOP_STRICTEQ || op == JSOP_STRICTNE;
}
}
return false;
}
/*
* Infer lookup flags from the currently executing bytecode, returning
* defaultFlags if a currently executing bytecode cannot be determined.
*/
unsigned
js_InferFlags(JSContext *cx, unsigned defaultFlags)
{
/*
* We intentionally want to look across compartment boundaries to correctly
* handle the case of cross-compartment property access.
*/
jsbytecode *pc;
JSScript *script = cx->currentScript(&pc, JSContext::ALLOW_CROSS_COMPARTMENT);
if (!script)
return defaultFlags;
uint32_t format = js_CodeSpec[*pc].format;
unsigned flags = 0;
if (format & JOF_SET)
flags |= JSRESOLVE_ASSIGNING;
return flags;
}
/* static */ bool
JSObject::nonNativeSetProperty(JSContext *cx, HandleObject obj,
HandleId id, MutableHandleValue vp, bool strict)
{
if (JS_UNLIKELY(obj->watched())) {
WatchpointMap *wpmap = cx->compartment()->watchpointMap;
if (wpmap && !wpmap->triggerWatchpoint(cx, obj, id, vp))
return false;
}
return obj->getOps()->setGeneric(cx, obj, id, vp, strict);
}
/* static */ bool
JSObject::nonNativeSetElement(JSContext *cx, HandleObject obj,
uint32_t index, MutableHandleValue vp, bool strict)
{
if (JS_UNLIKELY(obj->watched())) {
RootedId id(cx);
if (!IndexToId(cx, index, &id))
return false;
WatchpointMap *wpmap = cx->compartment()->watchpointMap;
if (wpmap && !wpmap->triggerWatchpoint(cx, obj, id, vp))
return false;
}
return obj->getOps()->setElement(cx, obj, index, vp, strict);
}
/* static */ bool
JSObject::deleteByValue(JSContext *cx, HandleObject obj, const Value &property, bool *succeeded)
{
uint32_t index;
if (IsDefinitelyIndex(property, &index))
return deleteElement(cx, obj, index, succeeded);
RootedValue propval(cx, property);
Rooted<SpecialId> sid(cx);
if (ValueIsSpecial(obj, &propval, &sid, cx))
return deleteSpecial(cx, obj, sid, succeeded);
JSAtom *name = ToAtom<CanGC>(cx, propval);
if (!name)
return false;
if (name->isIndex(&index))
return deleteElement(cx, obj, index, succeeded);
Rooted<PropertyName*> propname(cx, name->asPropertyName());
return deleteProperty(cx, obj, propname, succeeded);
}
JS_FRIEND_API(bool)
JS_CopyPropertyFrom(JSContext *cx, HandleId id, HandleObject target,
HandleObject obj)
{
// |obj| and |cx| are generally not same-compartment with |target| here.
assertSameCompartment(cx, obj, id);
Rooted<JSPropertyDescriptor> desc(cx);
if (!GetOwnPropertyDescriptor(cx, obj, id, &desc))
return false;
MOZ_ASSERT(desc.object());
// Silently skip JSPropertyOp-implemented accessors.
if (desc.getter() && !desc.hasGetterObject())
return true;
if (desc.setter() && !desc.hasSetterObject())
return true;
JSAutoCompartment ac(cx, target);
RootedId wrappedId(cx, id);
if (!cx->compartment()->wrap(cx, &desc))
return false;
if (!cx->compartment()->wrapId(cx, wrappedId.address()))
return false;
bool ignored;
return DefineOwnProperty(cx, target, wrappedId, desc, &ignored);
}
JS_FRIEND_API(bool)
JS_CopyPropertiesFrom(JSContext *cx, JSObject *targetArg, JSObject *objArg)
{
RootedObject target(cx, targetArg);
RootedObject obj(cx, objArg);
JSAutoCompartment ac(cx, obj);
AutoIdVector props(cx);
if (!GetPropertyNames(cx, obj, JSITER_OWNONLY | JSITER_HIDDEN, &props))
return false;
for (size_t i = 0; i < props.length(); ++i) {
if (!JS_CopyPropertyFrom(cx, props.handleAt(i), target, obj))
return false;
}
return true;
}
static bool
CopySlots(JSContext *cx, HandleObject from, HandleObject to)
{
JS_ASSERT(!from->isNative() && !to->isNative());
JS_ASSERT(from->getClass() == to->getClass());
size_t n = 0;
if (from->is<WrapperObject>() &&
(Wrapper::wrapperHandler(from)->flags() &
Wrapper::CROSS_COMPARTMENT)) {
to->setSlot(0, from->getSlot(0));
to->setSlot(1, from->getSlot(1));
n = 2;
}
size_t span = JSCLASS_RESERVED_SLOTS(from->getClass());
RootedValue v(cx);
for (; n < span; ++n) {
v = from->getSlot(n);
if (!cx->compartment()->wrap(cx, &v))
return false;
to->setSlot(n, v);
}
return true;
}
JSObject *
js::CloneObject(JSContext *cx, HandleObject obj, Handle<js::TaggedProto> proto, HandleObject parent)
{
if (!obj->isNative() && !obj->is<ProxyObject>()) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr,
JSMSG_CANT_CLONE_OBJECT);
return nullptr;
}
RootedObject clone(cx, NewObjectWithGivenProto(cx, obj->getClass(), proto, parent));
if (!clone)
return nullptr;
if (obj->isNative()) {
if (clone->is<JSFunction>() && (obj->compartment() != clone->compartment())) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr,
JSMSG_CANT_CLONE_OBJECT);
return nullptr;
}
if (obj->hasPrivate())
clone->setPrivate(obj->getPrivate());
} else {
JS_ASSERT(obj->is<ProxyObject>());
if (!CopySlots(cx, obj, clone))
return nullptr;
}
return clone;
}
JSObject *
js::CloneObjectLiteral(JSContext *cx, HandleObject parent, HandleObject srcObj)
{
Rooted<TypeObject*> typeObj(cx);
typeObj = cx->getNewType(&JSObject::class_, cx->global()->getOrCreateObjectPrototype(cx));
JS_ASSERT(srcObj->getClass() == &JSObject::class_);
AllocKind kind = GetBackgroundAllocKind(GuessObjectGCKind(srcObj->numFixedSlots()));
JS_ASSERT_IF(srcObj->isTenured(), kind == srcObj->tenuredGetAllocKind());
RootedShape shape(cx, srcObj->lastProperty());
return NewReshapedObject(cx, typeObj, parent, kind, shape);
}
struct JSObject::TradeGutsReserved {
Vector<Value> avals;
Vector<Value> bvals;
int newafixed;
int newbfixed;
RootedShape newashape;
RootedShape newbshape;
HeapSlot *newaslots;
HeapSlot *newbslots;
TradeGutsReserved(JSContext *cx)
: avals(cx), bvals(cx),
newafixed(0), newbfixed(0),
newashape(cx), newbshape(cx),
newaslots(nullptr), newbslots(nullptr)
{}
~TradeGutsReserved()
{
js_free(newaslots);
js_free(newbslots);
}
};
bool
JSObject::ReserveForTradeGuts(JSContext *cx, JSObject *aArg, JSObject *bArg,
TradeGutsReserved &reserved)
{
/*
* Avoid GC in here to avoid confusing the tracing code with our
* intermediate state.
*/
AutoSuppressGC suppress(cx);
RootedObject a(cx, aArg);
RootedObject b(cx, bArg);
JS_ASSERT(a->compartment() == b->compartment());
AutoCompartment ac(cx, a);
/*
* When performing multiple swaps between objects which may have different
* numbers of fixed slots, we reserve all space ahead of time so that the
* swaps can be performed infallibly.
*/
/*
* Swap prototypes and classes on the two objects, so that TradeGuts can
* preserve the types of the two objects.
*/
const Class *aClass = a->getClass();
const Class *bClass = b->getClass();
Rooted<TaggedProto> aProto(cx, a->getTaggedProto());
Rooted<TaggedProto> bProto(cx, b->getTaggedProto());
bool success;
if (!SetClassAndProto(cx, a, bClass, bProto, &success) || !success)
return false;
if (!SetClassAndProto(cx, b, aClass, aProto, &success) || !success)
return false;
if (a->tenuredSizeOfThis() == b->tenuredSizeOfThis())
return true;
/*
* If either object is native, it needs a new shape to preserve the
* invariant that objects with the same shape have the same number of
* inline slots. The fixed slots will be updated in place during TradeGuts.
* Non-native objects need to be reshaped according to the new count.
*/
if (a->isNative()) {
if (!a->generateOwnShape(cx))
return false;
} else {
reserved.newbshape = EmptyShape::getInitialShape(cx, aClass, aProto, a->getParent(), a->getMetadata(),
b->tenuredGetAllocKind());
if (!reserved.newbshape)
return false;
}
if (b->isNative()) {
if (!b->generateOwnShape(cx))
return false;
} else {
reserved.newashape = EmptyShape::getInitialShape(cx, bClass, bProto, b->getParent(), b->getMetadata(),
a->tenuredGetAllocKind());
if (!reserved.newashape)
return false;
}
/* The avals/bvals vectors hold all original values from the objects. */
if (!reserved.avals.reserve(a->slotSpan()))
return false;
if (!reserved.bvals.reserve(b->slotSpan()))
return false;
/*
* The newafixed/newbfixed hold the number of fixed slots in the objects
* after the swap. Adjust these counts according to whether the objects
* use their last fixed slot for storing private data.
*/
reserved.newafixed = a->numFixedSlots();
reserved.newbfixed = b->numFixedSlots();
if (aClass->hasPrivate()) {
reserved.newafixed++;
reserved.newbfixed--;
}
if (bClass->hasPrivate()) {
reserved.newbfixed++;
reserved.newafixed--;
}
JS_ASSERT(reserved.newafixed >= 0);
JS_ASSERT(reserved.newbfixed >= 0);
/*
* The newaslots/newbslots arrays hold any dynamic slots for the objects
* if they do not have enough fixed slots to accomodate the slots in the
* other object.
*/
unsigned adynamic = dynamicSlotsCount(reserved.newafixed, b->slotSpan());
unsigned bdynamic = dynamicSlotsCount(reserved.newbfixed, a->slotSpan());
if (adynamic) {
reserved.newaslots = cx->pod_malloc<HeapSlot>(adynamic);
if (!reserved.newaslots)
return false;
Debug_SetSlotRangeToCrashOnTouch(reserved.newaslots, adynamic);
}
if (bdynamic) {
reserved.newbslots = cx->pod_malloc<HeapSlot>(bdynamic);
if (!reserved.newbslots)
return false;
Debug_SetSlotRangeToCrashOnTouch(reserved.newbslots, bdynamic);
}
return true;
}
void
JSObject::TradeGuts(JSContext *cx, JSObject *a, JSObject *b, TradeGutsReserved &reserved)
{
JS_ASSERT(a->compartment() == b->compartment());
JS_ASSERT(a->is<JSFunction>() == b->is<JSFunction>());
/*
* Swap the object's types, to restore their initial type information.
* The prototypes and classes of the objects were swapped in ReserveForTradeGuts.
*/
{
AutoLockForCompilation lock(cx);
TypeObject *tmp = a->type_;
a->type_ = b->type_;
b->type_ = tmp;
}
/* Don't try to swap a JSFunction for a plain function JSObject. */
JS_ASSERT_IF(a->is<JSFunction>(), a->tenuredSizeOfThis() == b->tenuredSizeOfThis());
/*
* Regexp guts are more complicated -- we would need to migrate the
* refcounted JIT code blob for them across compartments instead of just
* swapping guts.
*/
JS_ASSERT(!a->is<RegExpObject>() && !b->is<RegExpObject>());
/* Arrays can use their fixed storage for elements. */
JS_ASSERT(!a->is<ArrayObject>() && !b->is<ArrayObject>());
/*
* Callers should not try to swap ArrayBuffer objects,
* these use a different slot representation from other objects.
*/
JS_ASSERT(!a->is<ArrayBufferObject>() && !b->is<ArrayBufferObject>());
/* Trade the guts of the objects. */
const size_t size = a->tenuredSizeOfThis();
if (size == b->tenuredSizeOfThis()) {
/*
* If the objects are the same size, then we make no assumptions about
* whether they have dynamically allocated slots and instead just copy
* them over wholesale.
*/
char tmp[mozilla::tl::Max<sizeof(JSFunction), sizeof(JSObject_Slots16)>::value];
JS_ASSERT(size <= sizeof(tmp));
{
AutoLockForCompilation lock(cx);
js_memcpy(tmp, a, size);
js_memcpy(a, b, size);
js_memcpy(b, tmp, size);
}
#ifdef JSGC_GENERATIONAL
/*
* Trigger post barriers for fixed slots. JSObject bits are barriered
* below, in common with the other case.
*/
for (size_t i = 0; i < a->numFixedSlots(); ++i) {
HeapSlot::writeBarrierPost(cx->runtime(), a, HeapSlot::Slot, i, a->getSlot(i));
HeapSlot::writeBarrierPost(cx->runtime(), b, HeapSlot::Slot, i, b->getSlot(i));
}
#endif
} else {
/*
* If the objects are of differing sizes, use the space we reserved
* earlier to save the slots from each object and then copy them into
* the new layout for the other object.
*/
uint32_t acap = a->slotSpan();
uint32_t bcap = b->slotSpan();
for (size_t i = 0; i < acap; i++)
reserved.avals.infallibleAppend(a->getSlot(i));
for (size_t i = 0; i < bcap; i++)
reserved.bvals.infallibleAppend(b->getSlot(i));
/* Done with the dynamic slots. */
if (a->hasDynamicSlots())
js_free(a->slots);
if (b->hasDynamicSlots())
js_free(b->slots);
void *apriv = a->hasPrivate() ? a->getPrivate() : nullptr;
void *bpriv = b->hasPrivate() ? b->getPrivate() : nullptr;
char tmp[sizeof(JSObject)];
{
AutoLockForCompilation lock(cx);
js_memcpy(&tmp, a, sizeof tmp);
js_memcpy(a, b, sizeof tmp);
js_memcpy(b, &tmp, sizeof tmp);
}
if (a->isNative())
a->shape_->setNumFixedSlots(reserved.newafixed);
else
a->shape_ = reserved.newashape;
a->slots = reserved.newaslots;
a->initSlotRange(0, reserved.bvals.begin(), bcap);
if (a->hasPrivate())
a->initPrivate(bpriv);
if (b->isNative())
b->shape_->setNumFixedSlots(reserved.newbfixed);
else
b->shape_ = reserved.newbshape;
b->slots = reserved.newbslots;
b->initSlotRange(0, reserved.avals.begin(), acap);
if (b->hasPrivate())
b->initPrivate(apriv);
/* Make sure the destructor for reserved doesn't free the slots. */
reserved.newaslots = nullptr;
reserved.newbslots = nullptr;
}
#ifdef JSGC_GENERATIONAL
Shape::writeBarrierPost(a->shape_, &a->shape_);
Shape::writeBarrierPost(b->shape_, &b->shape_);
types::TypeObject::writeBarrierPost(a->type_, &a->type_);
types::TypeObject::writeBarrierPost(b->type_, &b->type_);
#endif
if (a->inDictionaryMode())
a->lastProperty()->listp = &a->shape_;
if (b->inDictionaryMode())
b->lastProperty()->listp = &b->shape_;
#ifdef JSGC_INCREMENTAL
/*
* We need a write barrier here. If |a| was marked and |b| was not, then
* after the swap, |b|'s guts would never be marked. The write barrier
* solves this.
*
* Normally write barriers happen before the write. However, that's not
* necessary here because nothing is being destroyed. We're just swapping.
* We don't do the barrier before TradeGuts because ReserveForTradeGuts
* makes changes to the objects that might confuse the tracing code.
*/
JS::Zone *zone = a->zone();
if (zone->needsBarrier()) {
MarkChildren(zone->barrierTracer(), a);
MarkChildren(zone->barrierTracer(), b);
}
#endif
}
/* Use this method with extreme caution. It trades the guts of two objects. */
bool
JSObject::swap(JSContext *cx, HandleObject a, HandleObject b)
{
AutoMarkInDeadZone adc1(a->zone());
AutoMarkInDeadZone adc2(b->zone());
// Ensure swap doesn't cause a finalizer to not be run.
JS_ASSERT(IsBackgroundFinalized(a->tenuredGetAllocKind()) ==
IsBackgroundFinalized(b->tenuredGetAllocKind()));
JS_ASSERT(a->compartment() == b->compartment());
unsigned r = NotifyGCPreSwap(a, b);
TradeGutsReserved reserved(cx);
if (!ReserveForTradeGuts(cx, a, b, reserved)) {
NotifyGCPostSwap(b, a, r);
return false;
}
TradeGuts(cx, a, b, reserved);
NotifyGCPostSwap(a, b, r);
return true;
}
static bool
DefineStandardSlot(JSContext *cx, HandleObject obj, JSProtoKey key, JSAtom *atom,
HandleValue v, uint32_t attrs, bool &named)
{
RootedId id(cx, AtomToId(atom));
if (key != JSProto_Null) {
/*
* Initializing an actual standard class on a global object. If the
* property is not yet present, force it into a new one bound to a
* reserved slot. Otherwise, go through the normal property path.
*/
JS_ASSERT(obj->is<GlobalObject>());
JS_ASSERT(obj->isNative());
if (!obj->nativeLookup(cx, id)) {
obj->as<GlobalObject>().setConstructorPropertySlot(key, v);
uint32_t slot = GlobalObject::constructorPropertySlot(key);
if (!JSObject::addProperty(cx, obj, id, JS_PropertyStub, JS_StrictPropertyStub, slot, attrs, 0, 0))
return false;
named = true;
return true;
}
}
named = JSObject::defineGeneric(cx, obj, id,
v, JS_PropertyStub, JS_StrictPropertyStub, attrs);
return named;
}
static void
SetClassObject(JSObject *obj, JSProtoKey key, JSObject *cobj, JSObject *proto)
{
JS_ASSERT(!obj->getParent());
if (!obj->is<GlobalObject>())
return;
obj->as<GlobalObject>().setConstructor(key, ObjectOrNullValue(cobj));
obj->as<GlobalObject>().setPrototype(key, ObjectOrNullValue(proto));
}
static void
ClearClassObject(JSObject *obj, JSProtoKey key)
{
JS_ASSERT(!obj->getParent());
if (!obj->is<GlobalObject>())
return;
obj->as<GlobalObject>().setConstructor(key, UndefinedValue());
obj->as<GlobalObject>().setPrototype(key, UndefinedValue());
}
JSObject *
js::DefineConstructorAndPrototype(JSContext *cx, HandleObject obj, JSProtoKey key, HandleAtom atom,
JSObject *protoProto, const Class *clasp,
Native constructor, unsigned nargs,
const JSPropertySpec *ps, const JSFunctionSpec *fs,
const JSPropertySpec *static_ps, const JSFunctionSpec *static_fs,
JSObject **ctorp, AllocKind ctorKind)
{
/*
* Create a prototype object for this class.
*
* FIXME: lazy standard (built-in) class initialization and even older
* eager boostrapping code rely on all of these properties:
*
* 1. NewObject attempting to compute a default prototype object when
* passed null for proto; and
*
* 2. NewObject tolerating no default prototype (null proto slot value)
* due to this js_InitClass call coming from js_InitFunctionClass on an
* otherwise-uninitialized global.
*
* 3. NewObject allocating a JSFunction-sized GC-thing when clasp is
* &JSFunction::class_, not a JSObject-sized (smaller) GC-thing.
*
* The JS_NewObjectForGivenProto and JS_NewObject APIs also allow clasp to
* be &JSFunction::class_ (we could break compatibility easily). But
* fixing (3) is not enough without addressing the bootstrapping dependency
* on (1) and (2).
*/
/*
* Create the prototype object. (GlobalObject::createBlankPrototype isn't
* used because it parents the prototype object to the global and because
* it uses WithProto::Given. FIXME: Undo dependencies on this parentage
* [which already needs to happen for bug 638316], figure out nicer
* semantics for null-protoProto, and use createBlankPrototype.)
*/
RootedObject proto(cx, NewObjectWithClassProto(cx, clasp, protoProto, obj, SingletonObject));
if (!proto)
return nullptr;
/* After this point, control must exit via label bad or out. */
RootedObject ctor(cx);
bool named = false;
bool cached = false;
if (!constructor) {
/*
* Lacking a constructor, name the prototype (e.g., Math) unless this
* class (a) is anonymous, i.e. for internal use only; (b) the class
* of obj (the global object) is has a reserved slot indexed by key;
* and (c) key is not the null key.
*/
if (!(clasp->flags & JSCLASS_IS_ANONYMOUS) || !obj->is<GlobalObject>() ||
key == JSProto_Null)
{
uint32_t attrs = (clasp->flags & JSCLASS_IS_ANONYMOUS)
? JSPROP_READONLY | JSPROP_PERMANENT
: 0;
RootedValue value(cx, ObjectValue(*proto));
if (!DefineStandardSlot(cx, obj, key, atom, value, attrs, named))
goto bad;
}
ctor = proto;
} else {
/*
* Create the constructor, not using GlobalObject::createConstructor
* because the constructor currently must have |obj| as its parent.
* (FIXME: remove this dependency on the exact identity of the parent,
* perhaps as part of bug 638316.)
*/
RootedFunction fun(cx, NewFunction(cx, NullPtr(), constructor, nargs,
JSFunction::NATIVE_CTOR, obj, atom, ctorKind));
if (!fun)
goto bad;
/*
* Set the class object early for standard class constructors. Type
* inference may need to access these, and js_GetClassPrototype will
* fail if it tries to do a reentrant reconstruction of the class.
*/
if (key != JSProto_Null) {
SetClassObject(obj, key, fun, proto);
cached = true;
}
RootedValue value(cx, ObjectValue(*fun));
if (!DefineStandardSlot(cx, obj, key, atom, value, 0, named))
goto bad;
/*
* Optionally construct the prototype object, before the class has
* been fully initialized. Allow the ctor to replace proto with a
* different object, as is done for operator new.
*/
ctor = fun;
if (!LinkConstructorAndPrototype(cx, ctor, proto))
goto bad;
/* Bootstrap Function.prototype (see also JS_InitStandardClasses). */
Rooted<TaggedProto> tagged(cx, TaggedProto(proto));
if (ctor->getClass() == clasp && !ctor->splicePrototype(cx, clasp, tagged))
goto bad;
}
if (!DefinePropertiesAndBrand(cx, proto, ps, fs) ||
(ctor != proto && !DefinePropertiesAndBrand(cx, ctor, static_ps, static_fs)))
{
goto bad;
}
if (clasp->flags & (JSCLASS_FREEZE_PROTO|JSCLASS_FREEZE_CTOR)) {
JS_ASSERT_IF(ctor == proto, !(clasp->flags & JSCLASS_FREEZE_CTOR));
if (proto && (clasp->flags & JSCLASS_FREEZE_PROTO) && !JSObject::freeze(cx, proto))
goto bad;
if (ctor && (clasp->flags & JSCLASS_FREEZE_CTOR) && !JSObject::freeze(cx, ctor))
goto bad;
}
/* If this is a standard class, cache its prototype. */
if (!cached && key != JSProto_Null)
SetClassObject(obj, key, ctor, proto);
if (ctorp)
*ctorp = ctor;
return proto;
bad:
if (named) {
bool succeeded;
JSObject::deleteByValue(cx, obj, StringValue(atom), &succeeded);
}
if (cached)
ClearClassObject(obj, key);
return nullptr;
}
JSObject *
js_InitClass(JSContext *cx, HandleObject obj, JSObject *protoProto_,
const Class *clasp, Native constructor, unsigned nargs,
const JSPropertySpec *ps, const JSFunctionSpec *fs,
const JSPropertySpec *static_ps, const JSFunctionSpec *static_fs,
JSObject **ctorp, AllocKind ctorKind)
{
RootedObject protoProto(cx, protoProto_);
/* Assert mandatory function pointer members. */
JS_ASSERT(clasp->addProperty);
JS_ASSERT(clasp->delProperty);
JS_ASSERT(clasp->getProperty);
JS_ASSERT(clasp->setProperty);
JS_ASSERT(clasp->enumerate);
JS_ASSERT(clasp->resolve);
JS_ASSERT(clasp->convert);
RootedAtom atom(cx, Atomize(cx, clasp->name, strlen(clasp->name)));
if (!atom)
return nullptr;
/*
* All instances of the class will inherit properties from the prototype
* object we are about to create (in DefineConstructorAndPrototype), which
* in turn will inherit from protoProto.
*
* When initializing a standard class (other than Object), if protoProto is
* null, default to the Object prototype object. The engine's internal uses
* of js_InitClass depend on this nicety. Note that in
* js_InitFunctionAndObjectClasses, we specially hack the resolving table
* and then depend on js_GetClassPrototype here leaving protoProto nullptr
* and returning true.
*/
JSProtoKey key = JSCLASS_CACHED_PROTO_KEY(clasp);
if (key != JSProto_Null &&
!protoProto &&
!js_GetClassPrototype(cx, JSProto_Object, &protoProto)) {
return nullptr;
}
return DefineConstructorAndPrototype(cx, obj, key, atom, protoProto, clasp, constructor, nargs,
ps, fs, static_ps, static_fs, ctorp, ctorKind);
}
/* static */ inline bool
JSObject::updateSlotsForSpan(ThreadSafeContext *cx,
HandleObject obj, size_t oldSpan, size_t newSpan)
{
JS_ASSERT(cx->isThreadLocal(obj));
JS_ASSERT(oldSpan != newSpan);
size_t oldCount = dynamicSlotsCount(obj->numFixedSlots(), oldSpan);
size_t newCount = dynamicSlotsCount(obj->numFixedSlots(), newSpan);
if (oldSpan < newSpan) {
if (oldCount < newCount && !JSObject::growSlots(cx, obj, oldCount, newCount))
return false;
if (newSpan == oldSpan + 1)
obj->initSlotUnchecked(oldSpan, UndefinedValue());
else
obj->initializeSlotRange(oldSpan, newSpan - oldSpan);
} else {
/* Trigger write barriers on the old slots before reallocating. */
obj->prepareSlotRangeForOverwrite(newSpan, oldSpan);
obj->invalidateSlotRange(newSpan, oldSpan - newSpan);
if (oldCount > newCount)
JSObject::shrinkSlots(cx, obj, oldCount, newCount);
}
return true;
}
/* static */ bool
JSObject::setLastProperty(ThreadSafeContext *cx, HandleObject obj, HandleShape shape)
{
JS_ASSERT(cx->isThreadLocal(obj));
JS_ASSERT(!obj->inDictionaryMode());
JS_ASSERT(!shape->inDictionary());
JS_ASSERT(shape->compartment() == obj->compartment());
JS_ASSERT(shape->numFixedSlots() == obj->numFixedSlots());
size_t oldSpan = obj->lastProperty()->slotSpan();
size_t newSpan = shape->slotSpan();
if (oldSpan == newSpan) {
obj->shape_ = shape;
return true;
}
if (!updateSlotsForSpan(cx, obj, oldSpan, newSpan))
return false;
obj->shape_ = shape;
return true;
}
/* static */ bool
JSObject::setSlotSpan(ThreadSafeContext *cx, HandleObject obj, uint32_t span)
{
JS_ASSERT(cx->isThreadLocal(obj));
JS_ASSERT(obj->inDictionaryMode());
size_t oldSpan = obj->lastProperty()->base()->slotSpan();
if (oldSpan == span)
return true;
if (!JSObject::updateSlotsForSpan(cx, obj, oldSpan, span))
return false;
obj->lastProperty()->base()->setSlotSpan(span);
return true;
}
static HeapSlot *
AllocateSlots(ThreadSafeContext *cx, JSObject *obj, uint32_t nslots)
{
#ifdef JSGC_GENERATIONAL
if (cx->isJSContext())
return cx->asJSContext()->runtime()->gcNursery.allocateSlots(cx->asJSContext(), obj, nslots);
#endif
return cx->pod_malloc<HeapSlot>(nslots);
}
static HeapSlot *
ReallocateSlots(ThreadSafeContext *cx, JSObject *obj, HeapSlot *oldSlots,
uint32_t oldCount, uint32_t newCount)
{
#ifdef JSGC_GENERATIONAL
if (cx->isJSContext()) {
return cx->asJSContext()->runtime()->gcNursery.reallocateSlots(cx->asJSContext(),
obj, oldSlots,
oldCount, newCount);
}
#endif
return (HeapSlot *)cx->realloc_(oldSlots, oldCount * sizeof(HeapSlot),
newCount * sizeof(HeapSlot));
}
/* static */ bool
JSObject::growSlots(ThreadSafeContext *cx, HandleObject obj, uint32_t oldCount, uint32_t newCount)
{
JS_ASSERT(cx->isThreadLocal(obj));
JS_ASSERT(newCount > oldCount);
JS_ASSERT(newCount >= SLOT_CAPACITY_MIN);
/*
* Slot capacities are determined by the span of allocated objects. Due to
* the limited number of bits to store shape slots, object growth is
* throttled well before the slot capacity can overflow.
*/
JS_ASSERT(newCount < NELEMENTS_LIMIT);
/*
* If we are allocating slots for an object whose type is always created
* by calling 'new' on a particular script, bump the GC kind for that
* type to give these objects a larger number of fixed slots when future
* objects are constructed.
*/
if (!obj->hasLazyType() && !oldCount && obj->type()->hasNewScript()) {
JSObject *oldTemplate = obj->type()->newScript()->templateObject;
gc::AllocKind kind = gc::GetGCObjectFixedSlotsKind(oldTemplate->numFixedSlots());
uint32_t newScriptSlots = gc::GetGCKindSlots(kind);
if (newScriptSlots == obj->numFixedSlots() &&
gc::TryIncrementAllocKind(&kind) &&
cx->isJSContext())
{
JSContext *ncx = cx->asJSContext();
AutoEnterAnalysis enter(ncx);
Rooted<TypeObject*> typeObj(cx, obj->type());
RootedShape shape(cx, oldTemplate->lastProperty());
JSObject *reshapedObj = NewReshapedObject(ncx, typeObj, obj->getParent(), kind, shape,
MaybeSingletonObject);
if (!reshapedObj)
return false;
typeObj->newScript()->templateObject = reshapedObj;
typeObj->markStateChange(ncx);
}
}
// Global slots may be read during off thread compilation, and updates to
// their slot pointers need to be synchronized.
Maybe<AutoLockForCompilation> lock;
if (obj->is<GlobalObject>())
lock.construct(cx->asExclusiveContext());
if (!oldCount) {
obj->slots = AllocateSlots(cx, obj, newCount);
if (!obj->slots)
return false;
Debug_SetSlotRangeToCrashOnTouch(obj->slots, newCount);
return true;
}
HeapSlot *newslots = ReallocateSlots(cx, obj, obj->slots, oldCount, newCount);
if (!newslots)
return false; /* Leave slots at its old size. */
obj->slots = newslots;
Debug_SetSlotRangeToCrashOnTouch(obj->slots + oldCount, newCount - oldCount);
return true;
}
static void
FreeSlots(ThreadSafeContext *cx, HeapSlot *slots)
{
// Note: threads without a JSContext do not have access to nursery allocated things.
#ifdef JSGC_GENERATIONAL
if (cx->isJSContext())
return cx->asJSContext()->runtime()->gcNursery.freeSlots(cx->asJSContext(), slots);
#endif
js_free(slots);
}
/* static */ void
JSObject::shrinkSlots(ThreadSafeContext *cx, HandleObject obj, uint32_t oldCount, uint32_t newCount)
{
JS_ASSERT(cx->isThreadLocal(obj));
JS_ASSERT(newCount < oldCount);
if (newCount == 0) {
FreeSlots(cx, obj->slots);
obj->slots = nullptr;
return;
}
JS_ASSERT(newCount >= SLOT_CAPACITY_MIN);
// Global slots may be read during off thread compilation, and updates to
// their slot pointers need to be synchronized.
Maybe<AutoLockForCompilation> lock;
if (obj->is<GlobalObject>())
lock.construct(cx->asExclusiveContext());
HeapSlot *newslots = ReallocateSlots(cx, obj, obj->slots, oldCount, newCount);
if (!newslots)
return; /* Leave slots at its old size. */
obj->slots = newslots;
}
/* static */ bool
JSObject::sparsifyDenseElement(ExclusiveContext *cx, HandleObject obj, uint32_t index)
{
RootedValue value(cx, obj->getDenseElement(index));
JS_ASSERT(!value.isMagic(JS_ELEMENTS_HOLE));
JSObject::removeDenseElementForSparseIndex(cx, obj, index);
uint32_t slot = obj->slotSpan();
if (!obj->addDataProperty(cx, INT_TO_JSID(index), slot, JSPROP_ENUMERATE)) {
obj->setDenseElement(index, value);
return false;
}
JS_ASSERT(slot == obj->slotSpan() - 1);
obj->initSlot(slot, value);
return true;
}
/* static */ bool
JSObject::sparsifyDenseElements(js::ExclusiveContext *cx, HandleObject obj)
{
uint32_t initialized = obj->getDenseInitializedLength();
/* Create new properties with the value of non-hole dense elements. */
for (uint32_t i = 0; i < initialized; i++) {
if (obj->getDenseElement(i).isMagic(JS_ELEMENTS_HOLE))
continue;
if (!sparsifyDenseElement(cx, obj, i))
return false;
}
if (initialized)
obj->setDenseInitializedLength(0);
/*
* Reduce storage for dense elements which are now holes. Explicitly mark
* the elements capacity as zero, so that any attempts to add dense
* elements will be caught in ensureDenseElements.
*/
if (obj->getDenseCapacity()) {
obj->shrinkElements(cx, 0);
obj->getElementsHeader()->capacity = 0;
}
return true;
}
bool
JSObject::willBeSparseElements(uint32_t requiredCapacity, uint32_t newElementsHint)
{
JS_ASSERT(isNative());
JS_ASSERT(requiredCapacity > MIN_SPARSE_INDEX);
uint32_t cap = getDenseCapacity();
JS_ASSERT(requiredCapacity >= cap);
if (requiredCapacity >= NELEMENTS_LIMIT)
return true;
uint32_t minimalDenseCount = requiredCapacity / SPARSE_DENSITY_RATIO;
if (newElementsHint >= minimalDenseCount)
return false;
minimalDenseCount -= newElementsHint;
if (minimalDenseCount > cap)
return true;
uint32_t len = getDenseInitializedLength();
const Value *elems = getDenseElements();
for (uint32_t i = 0; i < len; i++) {
if (!elems[i].isMagic(JS_ELEMENTS_HOLE) && !--minimalDenseCount)
return false;
}
return true;
}
/* static */ JSObject::EnsureDenseResult
JSObject::maybeDensifySparseElements(js::ExclusiveContext *cx, HandleObject obj)
{
/*
* Wait until after the object goes into dictionary mode, which must happen
* when sparsely packing any array with more than MIN_SPARSE_INDEX elements
* (see PropertyTree::MAX_HEIGHT).
*/
if (!obj->inDictionaryMode())
return ED_SPARSE;
/*
* Only measure the number of indexed properties every log(n) times when
* populating the object.
*/
uint32_t slotSpan = obj->slotSpan();
if (slotSpan != RoundUpPow2(slotSpan))
return ED_SPARSE;
/* Watch for conditions under which an object's elements cannot be dense. */
if (!obj->nonProxyIsExtensible() || obj->watched())
return ED_SPARSE;
/*
* The indexes in the object need to be sufficiently dense before they can
* be converted to dense mode.
*/
uint32_t numDenseElements = 0;
uint32_t newInitializedLength = 0;
RootedShape shape(cx, obj->lastProperty());
while (!shape->isEmptyShape()) {
uint32_t index;
if (js_IdIsIndex(shape->propid(), &index)) {
if (shape->attributes() == JSPROP_ENUMERATE &&
shape->hasDefaultGetter() &&
shape->hasDefaultSetter())
{
numDenseElements++;
newInitializedLength = Max(newInitializedLength, index + 1);
} else {
/*
* For simplicity, only densify the object if all indexed
* properties can be converted to dense elements.
*/
return ED_SPARSE;
}
}
shape = shape->previous();
}
if (numDenseElements * SPARSE_DENSITY_RATIO < newInitializedLength)
return ED_SPARSE;
if (newInitializedLength >= NELEMENTS_LIMIT)
return ED_SPARSE;
/*
* This object meets all necessary restrictions, convert all indexed
* properties into dense elements.
*/
if (newInitializedLength > obj->getDenseCapacity()) {
if (!obj->growElements(cx, newInitializedLength))
return ED_FAILED;
}
obj->ensureDenseInitializedLength(cx, newInitializedLength, 0);
RootedValue value(cx);
shape = obj->lastProperty();
while (!shape->isEmptyShape()) {
jsid id = shape->propid();
uint32_t index;
if (js_IdIsIndex(id, &index)) {
value = obj->getSlot(shape->slot());
/*
* When removing a property from a dictionary, the specified
* property will be removed from the dictionary list and the
* last property will then be changed due to reshaping the object.
* Compute the next shape in the traverse, watching for such
* removals from the list.
*/
if (shape != obj->lastProperty()) {
shape = shape->previous();
if (!obj->removeProperty(cx, id))
return ED_FAILED;
} else {
if (!obj->removeProperty(cx, id))
return ED_FAILED;
shape = obj->lastProperty();
}
obj->setDenseElement(index, value);
} else {
shape = shape->previous();
}
}
/*
* All indexed properties on the object are now dense, clear the indexed
* flag so that we will not start using sparse indexes again if we need
* to grow the object.
*/
if (!obj->clearFlag(cx, BaseShape::INDEXED))
return ED_FAILED;
return ED_OK;
}
static ObjectElements *
AllocateElements(ThreadSafeContext *cx, JSObject *obj, uint32_t nelems)
{
#ifdef JSGC_GENERATIONAL
if (cx->isJSContext())
return cx->asJSContext()->runtime()->gcNursery.allocateElements(cx->asJSContext(), obj, nelems);
#endif
return static_cast<js::ObjectElements *>(cx->malloc_(nelems * sizeof(HeapValue)));
}
static ObjectElements *
ReallocateElements(ThreadSafeContext *cx, JSObject *obj, ObjectElements *oldHeader,
uint32_t oldCount, uint32_t newCount)
{
#ifdef JSGC_GENERATIONAL
if (cx->isJSContext()) {
return cx->asJSContext()->runtime()-> gcNursery.reallocateElements(cx->asJSContext(), obj, oldHeader,
oldCount, newCount);
}
#endif
return static_cast<js::ObjectElements *>(cx->realloc_(oldHeader, oldCount * sizeof(HeapSlot),
newCount * sizeof(HeapSlot)));
}
bool
JSObject::growElements(ThreadSafeContext *cx, uint32_t newcap)
{
JS_ASSERT(nonProxyIsExtensible());
/*
* When an object with CAPACITY_DOUBLING_MAX or fewer elements needs to
* grow, double its capacity, to add N elements in amortized O(N) time.
*
* Above this limit, grow by 12.5% each time. Speed is still amortized
* O(N), with a higher constant factor, and we waste less space.
*/
static const size_t CAPACITY_DOUBLING_MAX = 1024 * 1024;
static const size_t CAPACITY_CHUNK = CAPACITY_DOUBLING_MAX / sizeof(Value);
uint32_t oldcap = getDenseCapacity();
JS_ASSERT(oldcap <= newcap);
uint32_t nextsize = (oldcap <= CAPACITY_DOUBLING_MAX)
? oldcap * 2
: oldcap + (oldcap >> 3);
uint32_t actualCapacity;
if (is<ArrayObject>() && !as<ArrayObject>().lengthIsWritable()) {
JS_ASSERT(newcap <= as<ArrayObject>().length());
// Preserve the |capacity <= length| invariant for arrays with
// non-writable length. See also js::ArraySetLength which initially
// enforces this requirement.
actualCapacity = newcap;
} else {
actualCapacity = Max(newcap, nextsize);
if (actualCapacity >= CAPACITY_CHUNK)
actualCapacity = JS_ROUNDUP(actualCapacity, CAPACITY_CHUNK);
else if (actualCapacity < SLOT_CAPACITY_MIN)
actualCapacity = SLOT_CAPACITY_MIN;
/* Don't let nelements get close to wrapping around uint32_t. */
if (actualCapacity >= NELEMENTS_LIMIT || actualCapacity < oldcap || actualCapacity < newcap)
return false;
}
uint32_t initlen = getDenseInitializedLength();
uint32_t oldAllocated = oldcap + ObjectElements::VALUES_PER_HEADER;
uint32_t newAllocated = actualCapacity + ObjectElements::VALUES_PER_HEADER;
ObjectElements *newheader;
if (hasDynamicElements()) {
newheader = ReallocateElements(cx, this, getElementsHeader(), oldAllocated, newAllocated);
if (!newheader)
return false; /* Leave elements as its old size. */
} else {
newheader = AllocateElements(cx, this, newAllocated);
if (!newheader)
return false; /* Leave elements as its old size. */
js_memcpy(newheader, getElementsHeader(),
(ObjectElements::VALUES_PER_HEADER + initlen) * sizeof(Value));
}
newheader->capacity = actualCapacity;
elements = newheader->elements();
Debug_SetSlotRangeToCrashOnTouch(elements + initlen, actualCapacity - initlen);
return true;
}
void
JSObject::shrinkElements(ThreadSafeContext *cx, uint32_t newcap)
{
JS_ASSERT(cx->isThreadLocal(this));
uint32_t oldcap = getDenseCapacity();
JS_ASSERT(newcap <= oldcap);
/* Don't shrink elements below the minimum capacity. */
if (oldcap <= SLOT_CAPACITY_MIN || !hasDynamicElements())
return;
newcap = Max(newcap, SLOT_CAPACITY_MIN);
uint32_t oldAllocated = oldcap + ObjectElements::VALUES_PER_HEADER;
uint32_t newAllocated = newcap + ObjectElements::VALUES_PER_HEADER;
ObjectElements *newheader = ReallocateElements(cx, this, getElementsHeader(),
oldAllocated, newAllocated);
if (!newheader)
return; /* Leave elements at its old size. */
newheader->capacity = newcap;
elements = newheader->elements();
}
static JSObject *
js_InitNullClass(JSContext *cx, HandleObject obj)
{
JS_ASSERT(0);
return nullptr;
}
#define DECLARE_PROTOTYPE_CLASS_INIT(name,code,init,clasp) \
extern JSObject *init(JSContext *cx, Handle<JSObject*> obj);
JS_FOR_EACH_PROTOTYPE(DECLARE_PROTOTYPE_CLASS_INIT)
#undef DECLARE_PROTOTYPE_CLASS_INIT
static const ClassInitializerOp lazy_prototype_init[JSProto_LIMIT] = {
#define LAZY_PROTOTYPE_INIT(name,code,init,clasp) init,
JS_FOR_EACH_PROTOTYPE(LAZY_PROTOTYPE_INIT)
#undef LAZY_PROTOTYPE_INIT
};
bool
js::SetClassAndProto(JSContext *cx, HandleObject obj,
const Class *clasp, Handle<js::TaggedProto> proto,
bool *succeeded)
{
/*
* Regenerate shapes for all of the scopes along the old prototype chain,
* in case any entries were filled by looking up through obj. Stop when a
* non-native object is found, prototype lookups will not be cached across
* these.
*
* How this shape change is done is very delicate; the change can be made
* either by marking the object's prototype as uncacheable (such that the
* property cache and JIT'ed ICs cannot assume the shape determines the
* prototype) or by just generating a new shape for the object. Choosing
* the former is bad if the object is on the prototype chain of other
* objects, as the uncacheable prototype can inhibit iterator caches on
* those objects and slow down prototype accesses. Choosing the latter is
* bad if there are many similar objects to this one which will have their
* prototype mutated, as the generateOwnShape forces the object into
* dictionary mode and similar property lineages will be repeatedly cloned.
*
* :XXX: bug 707717 make this code less brittle.
*/
*succeeded = false;
RootedObject oldproto(cx, obj);
while (oldproto && oldproto->isNative()) {
if (oldproto->hasSingletonType()) {
if (!oldproto->generateOwnShape(cx))
return false;
} else {
if (!oldproto->setUncacheableProto(cx))
return false;
}
oldproto = oldproto->getProto();
}
if (obj->hasSingletonType()) {
/*
* Just splice the prototype, but mark the properties as unknown for
* consistent behavior.
*/
if (!obj->splicePrototype(cx, clasp, proto))
return false;
MarkTypeObjectUnknownProperties(cx, obj->type());
*succeeded = true;
return true;
}
if (proto.isObject()) {
RootedObject protoObj(cx, proto.toObject());
if (!JSObject::setNewTypeUnknown(cx, clasp, protoObj))
return false;
}
TypeObject *type = cx->getNewType(clasp, proto);
if (!type)
return false;
/*
* Setting __proto__ on an object that has escaped and may be referenced by
* other heap objects can only be done if the properties of both objects
* are unknown. Type sets containing this object will contain the original
* type but not the new type of the object, so we need to go and scan the
* entire compartment for type sets which have these objects and mark them
* as containing generic objects.
*/
MarkTypeObjectUnknownProperties(cx, obj->type(), true);
MarkTypeObjectUnknownProperties(cx, type, true);
{
AutoLockForCompilation lock(cx);
obj->setType(type);
}
*succeeded = true;
return true;
}
bool
js_GetClassObject(ExclusiveContext *cxArg, JSObject *obj, JSProtoKey key, MutableHandleObject objp)
{
Rooted<GlobalObject*> global(cxArg, &obj->global());
Value v = global->getConstructor(key);
if (v.isObject()) {
objp.set(&v.toObject());
return true;
}
// Classes can only be initialized on the main thread.
if (!cxArg->shouldBeJSContext())
return false;
JSContext *cx = cxArg->asJSContext();
RootedId name(cx, NameToId(ClassName(key, cx)));
AutoResolving resolving(cx, global, name);
if (resolving.alreadyStarted()) {
/* Already caching id in global -- suppress recursion. */
objp.set(nullptr);
return true;
}
RootedObject cobj(cx, nullptr);
if (ClassInitializerOp init = lazy_prototype_init[key]) {
if (!init(cx, global))
return false;
v = global->getConstructor(key);
if (v.isObject())
cobj = &v.toObject();
}
objp.set(cobj);
return true;
}
JSProtoKey
js_IdentifyClassPrototype(JSObject *obj)
{
// First, get the key off the JSClass. This tells us which prototype we
// _might_ be. But we still don't know for sure, since the prototype shares
// its JSClass with instances.
JSProtoKey key = JSCLASS_CACHED_PROTO_KEY(obj->getClass());
if (key == JSProto_Null)
return JSProto_Null;
// Now, see if the cached object matches |obj|.
//
// Note that standard class objects are cached in the range [0, JSProto_LIMIT),
// and the prototypes are cached in [JSProto_LIMIT, 2*JSProto_LIMIT).
GlobalObject &global = obj->global();
Value v = global.getPrototype(key);
if (v.isObject() && obj == &v.toObject())
return key;
// False alarm - just an instance.
return JSProto_Null;
}
bool
js_FindClassObject(ExclusiveContext *cx, JSProtoKey protoKey, MutableHandleValue vp, const Class *clasp)
{
RootedId id(cx);
if (protoKey != JSProto_Null) {
JS_ASSERT(JSProto_Null < protoKey);
JS_ASSERT(protoKey < JSProto_LIMIT);
RootedObject cobj(cx);
if (!js_GetClassObject(cx, cx->global(), protoKey, &cobj))
return false;
if (cobj) {
vp.set(ObjectValue(*cobj));
return true;
}
id = NameToId(ClassName(protoKey, cx));
} else {
JSAtom *atom = Atomize(cx, clasp->name, strlen(clasp->name));
if (!atom)
return false;
id = AtomToId(atom);
}
RootedObject pobj(cx);
RootedShape shape(cx);
if (!LookupPropertyWithFlags(cx, cx->global(), id, 0, &pobj, &shape))
return false;
RootedValue v(cx, UndefinedValue());
if (shape && pobj->isNative()) {
if (shape->hasSlot()) {
v = pobj->nativeGetSlot(shape->slot());
if (v.get().isPrimitive())
v.get().setUndefined();
}
}
vp.set(v);
return true;
}
/* static */ bool
JSObject::allocSlot(ThreadSafeContext *cx, HandleObject obj, uint32_t *slotp)
{
JS_ASSERT(cx->isThreadLocal(obj));
uint32_t slot = obj->slotSpan();
JS_ASSERT(slot >= JSSLOT_FREE(obj->getClass()));
/*
* If this object is in dictionary mode, try to pull a free slot from the
* shape table's slot-number freelist.
*/
if (obj->inDictionaryMode()) {
ShapeTable &table = obj->lastProperty()->table();
uint32_t last = table.freelist;
if (last != SHAPE_INVALID_SLOT) {
#ifdef DEBUG
JS_ASSERT(last < slot);
uint32_t next = obj->getSlot(last).toPrivateUint32();
JS_ASSERT_IF(next != SHAPE_INVALID_SLOT, next < slot);
#endif
*slotp = last;
const Value &vref = obj->getSlot(last);
table.freelist = vref.toPrivateUint32();
obj->setSlot(last, UndefinedValue());
return true;
}
}
if (slot >= SHAPE_MAXIMUM_SLOT) {
js_ReportOutOfMemory(cx);
return false;
}
*slotp = slot;
if (obj->inDictionaryMode() && !setSlotSpan(cx, obj, slot + 1))
return false;
return true;
}
void
JSObject::freeSlot(uint32_t slot)
{
JS_ASSERT(slot < slotSpan());
if (inDictionaryMode()) {
uint32_t &last = lastProperty()->table().freelist;
/* Can't afford to check the whole freelist, but let's check the head. */
JS_ASSERT_IF(last != SHAPE_INVALID_SLOT, last < slotSpan() && last != slot);
/*
* Place all freed slots other than reserved slots (bug 595230) on the
* dictionary's free list.
*/
if (JSSLOT_FREE(getClass()) <= slot) {
JS_ASSERT_IF(last != SHAPE_INVALID_SLOT, last < slotSpan());
setSlot(slot, PrivateUint32Value(last));
last = slot;
return;
}
}
setSlot(slot, UndefinedValue());
}
static bool
PurgeProtoChain(ExclusiveContext *cx, JSObject *objArg, HandleId id)
{
/* Root locally so we can re-assign. */
RootedObject obj(cx, objArg);
RootedShape shape(cx);
while (obj) {
/* Lookups will not be cached through non-native protos. */
if (!obj->isNative())
break;
shape = obj->nativeLookup(cx, id);
if (shape) {
if (!obj->shadowingShapeChange(cx, *shape))
return false;
obj->shadowingShapeChange(cx, *shape);
return true;
}
obj = obj->getProto();
}
return true;
}
static bool
PurgeScopeChainHelper(ExclusiveContext *cx, HandleObject objArg, HandleId id)
{
/* Re-root locally so we can re-assign. */
RootedObject obj(cx, objArg);
JS_ASSERT(obj->isNative());
JS_ASSERT(obj->isDelegate());
/* Lookups on integer ids cannot be cached through prototypes. */
if (JSID_IS_INT(id))
return true;
PurgeProtoChain(cx, obj->getProto(), id);
/*
* We must purge the scope chain only for Call objects as they are the only
* kind of cacheable non-global object that can gain properties after outer
* properties with the same names have been cached or traced. Call objects
* may gain such properties via eval introducing new vars; see bug 490364.
*/
if (obj->is<CallObject>()) {
while ((obj = obj->enclosingScope()) != nullptr) {
if (!PurgeProtoChain(cx, obj, id))
return false;
}
}
return true;
}
/*
* PurgeScopeChain does nothing if obj is not itself a prototype or parent
* scope, else it reshapes the scope and prototype chains it links. It calls
* PurgeScopeChainHelper, which asserts that obj is flagged as a delegate
* (i.e., obj has ever been on a prototype or parent chain).
*/
static inline bool
PurgeScopeChain(ExclusiveContext *cx, JS::HandleObject obj, JS::HandleId id)
{
if (obj->isDelegate())
return PurgeScopeChainHelper(cx, obj, id);
return true;
}
bool
baseops::DefineGeneric(ExclusiveContext *cx, HandleObject obj, HandleId id, HandleValue value,
PropertyOp getter, StrictPropertyOp setter, unsigned attrs)
{
return DefineNativeProperty(cx, obj, id, value, getter, setter, attrs, 0, 0);
}
/* static */ bool
JSObject::defineGeneric(ExclusiveContext *cx, HandleObject obj,
HandleId id, HandleValue value,
JSPropertyOp getter, JSStrictPropertyOp setter, unsigned attrs)
{
JS_ASSERT(!(attrs & JSPROP_NATIVE_ACCESSORS));
js::DefineGenericOp op = obj->getOps()->defineGeneric;
if (op) {
if (!cx->shouldBeJSContext())
return false;
return op(cx->asJSContext(), obj, id, value, getter, setter, attrs);
}
return baseops::DefineGeneric(cx, obj, id, value, getter, setter, attrs);
}
/* static */ bool
JSObject::defineProperty(ExclusiveContext *cx, HandleObject obj,
PropertyName *name, HandleValue value,
JSPropertyOp getter, JSStrictPropertyOp setter, unsigned attrs)
{
RootedId id(cx, NameToId(name));
return defineGeneric(cx, obj, id, value, getter, setter, attrs);
}
/* static */ bool
JSObject::defineSpecial(ExclusiveContext *cx, HandleObject obj,
SpecialId sid, HandleValue value,
JSPropertyOp getter, JSStrictPropertyOp setter, unsigned attrs)
{
RootedId id(cx, SPECIALID_TO_JSID(sid));
return defineGeneric(cx, obj, id, value, getter, setter, attrs);
}
bool
baseops::DefineElement(ExclusiveContext *cx, HandleObject obj, uint32_t index, HandleValue value,
PropertyOp getter, StrictPropertyOp setter, unsigned attrs)
{
RootedId id(cx);
if (index <= JSID_INT_MAX) {
id = INT_TO_JSID(index);
return DefineNativeProperty(cx, obj, id, value, getter, setter, attrs, 0, 0);
}
AutoRooterGetterSetter gsRoot(cx, attrs, &getter, &setter);
if (!IndexToId(cx, index, &id))
return false;
return DefineNativeProperty(cx, obj, id, value, getter, setter, attrs, 0, 0);
}
/* static */ bool
JSObject::defineElement(ExclusiveContext *cx, HandleObject obj,
uint32_t index, HandleValue value,
JSPropertyOp getter, JSStrictPropertyOp setter, unsigned attrs)
{
js::DefineElementOp op = obj->getOps()->defineElement;
if (op) {
if (!cx->shouldBeJSContext())
return false;
return op(cx->asJSContext(), obj, index, value, getter, setter, attrs);
}
return baseops::DefineElement(cx, obj, index, value, getter, setter, attrs);
}
Shape *
JSObject::addDataProperty(ExclusiveContext *cx, jsid idArg, uint32_t slot, unsigned attrs)
{
JS_ASSERT(!(attrs & (JSPROP_GETTER | JSPROP_SETTER)));
RootedObject self(cx, this);
RootedId id(cx, idArg);
return addProperty(cx, self, id, nullptr, nullptr, slot, attrs, 0, 0);
}
Shape *
JSObject::addDataProperty(ExclusiveContext *cx, HandlePropertyName name,
uint32_t slot, unsigned attrs)
{
JS_ASSERT(!(attrs & (JSPROP_GETTER | JSPROP_SETTER)));
RootedObject self(cx, this);
RootedId id(cx, NameToId(name));
return addProperty(cx, self, id, nullptr, nullptr, slot, attrs, 0, 0);
}
/*
* Backward compatibility requires allowing addProperty hooks to mutate the
* nominal initial value of a slotful property, while GC safety wants that
* value to be stored before the call-out through the hook. Optimize to do
* both while saving cycles for classes that stub their addProperty hook.
*/
template <ExecutionMode mode>
static inline bool
CallAddPropertyHook(typename ExecutionModeTraits<mode>::ExclusiveContextType cxArg,
const Class *clasp, HandleObject obj, HandleShape shape,
HandleValue nominal)
{
if (clasp->addProperty != JS_PropertyStub) {
if (mode == ParallelExecution)
return false;
ExclusiveContext *cx = cxArg->asExclusiveContext();
if (!cx->shouldBeJSContext())
return false;
/* Make a local copy of value so addProperty can mutate its inout parameter. */
RootedValue value(cx, nominal);
Rooted<jsid> id(cx, shape->propid());
if (!CallJSPropertyOp(cx->asJSContext(), clasp->addProperty, obj, id, &value)) {
obj->removeProperty(cx, shape->propid());
return false;
}
if (value.get() != nominal) {
if (shape->hasSlot())
obj->nativeSetSlotWithType(cx, shape, value);
}
}
return true;
}
template <ExecutionMode mode>
static inline bool
CallAddPropertyHookDense(typename ExecutionModeTraits<mode>::ExclusiveContextType cxArg,
const Class *clasp, HandleObject obj, uint32_t index,
HandleValue nominal)
{
/* Inline addProperty for array objects. */
if (obj->is<ArrayObject>()) {
Rooted<ArrayObject*> arr(cxArg, &obj->as<ArrayObject>());
uint32_t length = arr->length();
if (index >= length) {
if (mode == ParallelExecution) {
/* We cannot deal with overflows in parallel. */
if (length > INT32_MAX)
return false;
arr->setLengthInt32(index + 1);
} else {
ArrayObject::setLength(cxArg->asExclusiveContext(), arr, index + 1);
}
}
return true;
}
if (clasp->addProperty != JS_PropertyStub) {
if (mode == ParallelExecution)
return false;
ExclusiveContext *cx = cxArg->asExclusiveContext();
if (!cx->shouldBeJSContext())
return false;
/* Make a local copy of value so addProperty can mutate its inout parameter. */
RootedValue value(cx, nominal);
Rooted<jsid> id(cx, INT_TO_JSID(index));
if (!CallJSPropertyOp(cx->asJSContext(), clasp->addProperty, obj, id, &value)) {
obj->setDenseElementHole(cx, index);
return false;
}
if (value.get() != nominal)
obj->setDenseElementWithType(cx, index, value);
}
return true;
}
template <ExecutionMode mode>
static bool
UpdateShapeTypeAndValue(typename ExecutionModeTraits<mode>::ExclusiveContextType cx,
JSObject *obj, Shape *shape, const Value &value)
{
jsid id = shape->propid();
if (shape->hasSlot()) {
if (mode == ParallelExecution) {
if (!obj->nativeSetSlotIfHasType(shape, value))
return false;
} else {
obj->nativeSetSlotWithType(cx->asExclusiveContext(), shape, value);
}
}
if (!shape->hasSlot() || !shape->writable() ||
!shape->hasDefaultGetter() || !shape->hasDefaultSetter())
{
if (mode == ParallelExecution) {
if (!IsTypePropertyIdMarkedConfigured(obj, id))
return false;
} else {
MarkTypePropertyConfigured(cx->asExclusiveContext(), obj, id);
}
}
return true;
}
template <ExecutionMode mode>
static inline bool
DefinePropertyOrElement(typename ExecutionModeTraits<mode>::ExclusiveContextType cx,
HandleObject obj, HandleId id,
PropertyOp getter, StrictPropertyOp setter,
unsigned attrs, unsigned flags, int shortid,
HandleValue value, bool callSetterAfterwards, bool setterIsStrict)
{
/* Use dense storage for new indexed properties where possible. */
if (JSID_IS_INT(id) &&
getter == JS_PropertyStub &&
setter == JS_StrictPropertyStub &&
attrs == JSPROP_ENUMERATE &&
(!obj->isIndexed() || !obj->nativeContainsPure(id)))
{
uint32_t index = JSID_TO_INT(id);
bool definesPast;
if (!WouldDefinePastNonwritableLength(cx, obj, index, setterIsStrict, &definesPast))
return false;
if (definesPast)
return true;
JSObject::EnsureDenseResult result;
if (mode == ParallelExecution) {
if (obj->writeToIndexWouldMarkNotPacked(index))
return false;
result = obj->ensureDenseElementsPreservePackedFlag(cx, index, 1);
} else {
result = obj->ensureDenseElements(cx->asExclusiveContext(), index, 1);
}
if (result == JSObject::ED_FAILED)
return false;
if (result == JSObject::ED_OK) {
if (mode == ParallelExecution) {
if (!obj->setDenseElementIfHasType(index, value))
return false;
} else {
obj->setDenseElementWithType(cx->asExclusiveContext(), index, value);
}
return CallAddPropertyHookDense<mode>(cx, obj->getClass(), obj, index, value);
}
}
if (obj->is<ArrayObject>()) {
Rooted<ArrayObject*> arr(cx, &obj->as<ArrayObject>());
if (id == NameToId(cx->names().length)) {
if (mode == SequentialExecution && !cx->shouldBeJSContext())
return false;
return ArraySetLength<mode>(ExecutionModeTraits<mode>::toContextType(cx), arr, id,
attrs, value, setterIsStrict);
}
uint32_t index;
if (js_IdIsIndex(id, &index)) {
bool definesPast;
if (!WouldDefinePastNonwritableLength(cx, arr, index, setterIsStrict, &definesPast))
return false;
if (definesPast)
return true;
}
}
AutoRooterGetterSetter gsRoot(cx, attrs, &getter, &setter);
RootedShape shape(cx, JSObject::putProperty<mode>(cx, obj, id, getter, setter,
SHAPE_INVALID_SLOT,
attrs, flags, shortid));
if (!shape)
return false;
if (!UpdateShapeTypeAndValue<mode>(cx, obj, shape, value))
return false;
/*
* Clear any existing dense index after adding a sparse indexed property,
* and investigate converting the object to dense indexes.
*/
if (JSID_IS_INT(id)) {
if (mode == ParallelExecution)
return false;
ExclusiveContext *ncx = cx->asExclusiveContext();
uint32_t index = JSID_TO_INT(id);
JSObject::removeDenseElementForSparseIndex(ncx, obj, index);
JSObject::EnsureDenseResult result = JSObject::maybeDensifySparseElements(ncx, obj);
if (result == JSObject::ED_FAILED)
return false;
if (result == JSObject::ED_OK) {
JS_ASSERT(setter == JS_StrictPropertyStub);
return CallAddPropertyHookDense<mode>(cx, obj->getClass(), obj, index, value);
}
}
if (!CallAddPropertyHook<mode>(cx, obj->getClass(), obj, shape, value))
return false;
if (callSetterAfterwards && setter != JS_StrictPropertyStub) {
if (!cx->shouldBeJSContext())
return false;
RootedValue nvalue(cx, value);
return NativeSet<mode>(ExecutionModeTraits<mode>::toContextType(cx),
obj, obj, shape, setterIsStrict, &nvalue);
}
return true;
}
static bool
NativeLookupOwnProperty(ExclusiveContext *cx, HandleObject obj, HandleId id, unsigned flags,
MutableHandle<Shape*> shapep);
bool
js::DefineNativeProperty(ExclusiveContext *cx, HandleObject obj, HandleId id, HandleValue value,
PropertyOp getter, StrictPropertyOp setter, unsigned attrs,
unsigned flags, int shortid, unsigned defineHow /* = 0 */)
{
JS_ASSERT((defineHow & ~DNP_DONT_PURGE) == 0);
JS_ASSERT(!(attrs & JSPROP_NATIVE_ACCESSORS));
AutoRooterGetterSetter gsRoot(cx, attrs, &getter, &setter);
/*
* If defining a getter or setter, we must check for its counterpart and
* update the attributes and property ops. A getter or setter is really
* only half of a property.
*/
RootedShape shape(cx);
if (attrs & (JSPROP_GETTER | JSPROP_SETTER)) {
/*
* If we are defining a getter whose setter was already defined, or
* vice versa, finish the job via obj->changeProperty.
*/
if (!NativeLookupOwnProperty(cx, obj, id, flags, &shape))
return false;
if (shape) {
if (IsImplicitDenseElement(shape)) {
if (!JSObject::sparsifyDenseElement(cx, obj, JSID_TO_INT(id)))
return false;
shape = obj->nativeLookup(cx, id);
}
if (shape->isAccessorDescriptor()) {
shape = JSObject::changeProperty<SequentialExecution>(cx, obj, shape, attrs,
JSPROP_GETTER | JSPROP_SETTER,
(attrs & JSPROP_GETTER)
? getter
: shape->getter(),
(attrs & JSPROP_SETTER)
? setter
: shape->setter());
if (!shape)
return false;
} else {
shape = nullptr;
}
}
}
/*
* Purge the property cache of any properties named by id that are about
* to be shadowed in obj's scope chain unless it is known a priori that it
* is not possible.
*/
if (!(defineHow & DNP_DONT_PURGE)) {
if (!PurgeScopeChain(cx, obj, id))
return false;
}
/* Use the object's class getter and setter by default. */
const Class *clasp = obj->getClass();
if (!getter && !(attrs & JSPROP_GETTER))
getter = clasp->getProperty;
if (!setter && !(attrs & JSPROP_SETTER))
setter = clasp->setProperty;
if (!shape) {
return DefinePropertyOrElement<SequentialExecution>(cx, obj, id, getter, setter,
attrs, flags, shortid, value,
false, false);
}
JS_ALWAYS_TRUE(UpdateShapeTypeAndValue<SequentialExecution>(cx, obj, shape, value));
return CallAddPropertyHook<SequentialExecution>(cx, clasp, obj, shape, value);
}
/*
* Call obj's resolve hook.
*
* cx, id, and flags are the parameters initially passed to the ongoing lookup;
* objp and propp are its out parameters. obj is an object along the prototype
* chain from where the lookup started.
*
* There are four possible outcomes:
*
* - On failure, report an error or exception and return false.
*
* - If we are already resolving a property of *curobjp, set *recursedp = true,
* and return true.
*
* - If the resolve hook finds or defines the sought property, set *objp and
* *propp appropriately, set *recursedp = false, and return true.
*
* - Otherwise no property was resolved. Set *propp = nullptr and
* *recursedp = false and return true.
*/
static JS_ALWAYS_INLINE bool
CallResolveOp(JSContext *cx, HandleObject obj, HandleId id, unsigned flags,
MutableHandleObject objp, MutableHandleShape propp, bool *recursedp)
{
const Class *clasp = obj->getClass();
JSResolveOp resolve = clasp->resolve;
/*
* Avoid recursion on (obj, id) already being resolved on cx.
*
* Once we have successfully added an entry for (obj, key) to
* cx->resolvingTable, control must go through cleanup: before
* returning. But note that JS_DHASH_ADD may find an existing
* entry, in which case we bail to suppress runaway recursion.
*/
AutoResolving resolving(cx, obj, id);
if (resolving.alreadyStarted()) {
/* Already resolving id in obj -- suppress recursion. */
*recursedp = true;
return true;
}
*recursedp = false;
propp.set(nullptr);
if (clasp->flags & JSCLASS_NEW_RESOLVE) {
JSNewResolveOp newresolve = reinterpret_cast<JSNewResolveOp>(resolve);
if (flags == RESOLVE_INFER)
flags = js_InferFlags(cx, 0);
RootedObject obj2(cx, nullptr);
if (!newresolve(cx, obj, id, flags, &obj2))
return false;
/*
* We trust the new style resolve hook to set obj2 to nullptr when
* the id cannot be resolved. But, when obj2 is not null, we do
* not assume that id must exist and do full nativeLookup for
* compatibility.
*/
if (!obj2)
return true;
if (!obj2->isNative()) {
/* Whoops, newresolve handed back a foreign obj2. */
JS_ASSERT(obj2 != obj);
return JSObject::lookupGeneric(cx, obj2, id, objp, propp);
}
objp.set(obj2);
} else {
if (!resolve(cx, obj, id))
return false;
objp.set(obj);
}
if (JSID_IS_INT(id) && objp->containsDenseElement(JSID_TO_INT(id))) {
MarkDenseElementFound<CanGC>(propp);
return true;
}
Shape *shape;
if (!objp->nativeEmpty() && (shape = objp->nativeLookup(cx, id)))
propp.set(shape);
else
objp.set(nullptr);
return true;
}
template <AllowGC allowGC>
static JS_ALWAYS_INLINE bool
LookupOwnPropertyWithFlagsInline(ExclusiveContext *cx,
typename MaybeRooted<JSObject*, allowGC>::HandleType obj,
typename MaybeRooted<jsid, allowGC>::HandleType id,
unsigned flags,
typename MaybeRooted<JSObject*, allowGC>::MutableHandleType objp,
typename MaybeRooted<Shape*, allowGC>::MutableHandleType propp,
bool *donep)
{
// Check for a native dense element.
if (JSID_IS_INT(id) && obj->containsDenseElement(JSID_TO_INT(id))) {
objp.set(obj);
MarkDenseElementFound<allowGC>(propp);
*donep = true;
return true;
}
// Check for a native property.
if (Shape *shape = obj->nativeLookup(cx, id)) {
objp.set(obj);
propp.set(shape);
*donep = true;
return true;
}
// id was not found in obj. Try obj's resolve hook, if any.
if (obj->getClass()->resolve != JS_ResolveStub) {
if (!cx->shouldBeJSContext() || !allowGC)
return false;
bool recursed;
if (!CallResolveOp(cx->asJSContext(),
MaybeRooted<JSObject*, allowGC>::toHandle(obj),
MaybeRooted<jsid, allowGC>::toHandle(id),
flags,
MaybeRooted<JSObject*, allowGC>::toMutableHandle(objp),
MaybeRooted<Shape*, allowGC>::toMutableHandle(propp),
&recursed))
{
return false;
}
if (recursed) {
objp.set(nullptr);
propp.set(nullptr);
*donep = true;
return true;
}
if (propp) {
*donep = true;
return true;
}
}
*donep = false;
return true;
}
static bool
NativeLookupOwnProperty(ExclusiveContext *cx, HandleObject obj, HandleId id, unsigned flags,
MutableHandle<Shape*> shapep)
{
RootedObject pobj(cx);
bool done;
if (!LookupOwnPropertyWithFlagsInline<CanGC>(cx, obj, id, flags, &pobj, shapep, &done))
return false;
if (!done || pobj != obj)
shapep.set(nullptr);
return true;
}
template <AllowGC allowGC>
static JS_ALWAYS_INLINE bool
LookupPropertyWithFlagsInline(ExclusiveContext *cx,
typename MaybeRooted<JSObject*, allowGC>::HandleType obj,
typename MaybeRooted<jsid, allowGC>::HandleType id,
unsigned flags,
typename MaybeRooted<JSObject*, allowGC>::MutableHandleType objp,
typename MaybeRooted<Shape*, allowGC>::MutableHandleType propp)
{
/* NB: The logic of this procedure is implicitly reflected in IonBuilder.cpp's
* |CanEffectlesslyCallLookupGenericOnObject| logic.
* If this changes, please remember to update the logic there as well.
*/
/* Search scopes starting with obj and following the prototype link. */
typename MaybeRooted<JSObject*, allowGC>::RootType current(cx, obj);
while (true) {
bool done;
if (!LookupOwnPropertyWithFlagsInline<allowGC>(cx, current, id, flags, objp, propp, &done))
return false;
if (done)
return true;
typename MaybeRooted<JSObject*, allowGC>::RootType proto(cx, current->getProto());
if (!proto)
break;
if (!proto->isNative()) {
if (!cx->shouldBeJSContext() || !allowGC)
return false;
return JSObject::lookupGeneric(cx->asJSContext(),
MaybeRooted<JSObject*, allowGC>::toHandle(proto),
MaybeRooted<jsid, allowGC>::toHandle(id),
MaybeRooted<JSObject*, allowGC>::toMutableHandle(objp),
MaybeRooted<Shape*, allowGC>::toMutableHandle(propp));
}
current = proto;
}
objp.set(nullptr);
propp.set(nullptr);
return true;
}
template <AllowGC allowGC>
bool
baseops::LookupProperty(ExclusiveContext *cx,
typename MaybeRooted<JSObject*, allowGC>::HandleType obj,
typename MaybeRooted<jsid, allowGC>::HandleType id,
typename MaybeRooted<JSObject*, allowGC>::MutableHandleType objp,
typename MaybeRooted<Shape*, allowGC>::MutableHandleType propp)
{
/* NB: The logic of this procedure is implicitly reflected in IonBuilder.cpp's
* |CanEffectlesslyCallLookupGenericOnObject| logic.
* If this changes, please remember to update the logic there as well.
*/
uint32_t resolveFlags =
cx->isJSContext() ? cx->asJSContext()->resolveFlags : 0;
return LookupPropertyWithFlagsInline<allowGC>(cx, obj, id, resolveFlags, objp, propp);
}
template bool
baseops::LookupProperty<CanGC>(ExclusiveContext *cx, HandleObject obj, HandleId id,
MutableHandleObject objp, MutableHandleShape propp);
template bool
baseops::LookupProperty<NoGC>(ExclusiveContext *cx, JSObject *obj, jsid id,
FakeMutableHandle<JSObject*> objp,
FakeMutableHandle<Shape*> propp);
/* static */ bool
JSObject::lookupGeneric(JSContext *cx, HandleObject obj, js::HandleId id,
MutableHandleObject objp, MutableHandleShape propp)
{
/*
* NB: The logic of lookupGeneric is implicitly reflected in IonBuilder.cpp's
* |CanEffectlesslyCallLookupGenericOnObject| logic.
* If this changes, please remember to update the logic there as well.
*/
LookupGenericOp op = obj->getOps()->lookupGeneric;
if (op)
return op(cx, obj, id, objp, propp);
return baseops::LookupProperty<js::CanGC>(cx, obj, id, objp, propp);
}
bool
baseops::LookupElement(JSContext *cx, HandleObject obj, uint32_t index,
MutableHandleObject objp, MutableHandleShape propp)
{
RootedId id(cx);
if (!IndexToId(cx, index, &id))
return false;
return LookupPropertyWithFlagsInline<CanGC>(cx, obj, id, cx->resolveFlags, objp, propp);
}
bool
js::LookupPropertyWithFlags(ExclusiveContext *cx, HandleObject obj, HandleId id, unsigned flags,
MutableHandleObject objp, MutableHandleShape propp)
{
return LookupPropertyWithFlagsInline<CanGC>(cx, obj, id, flags, objp, propp);
}
bool
js::LookupName(JSContext *cx, HandlePropertyName name, HandleObject scopeChain,
MutableHandleObject objp, MutableHandleObject pobjp, MutableHandleShape propp)
{
RootedId id(cx, NameToId(name));
for (RootedObject scope(cx, scopeChain); scope; scope = scope->enclosingScope()) {
if (!JSObject::lookupGeneric(cx, scope, id, pobjp, propp))
return false;
if (propp) {
objp.set(scope);
return true;
}
}
objp.set(nullptr);
pobjp.set(nullptr);
propp.set(nullptr);
return true;
}
bool
js::LookupNameNoGC(JSContext *cx, PropertyName *name, JSObject *scopeChain,
JSObject **objp, JSObject **pobjp, Shape **propp)
{
AutoAssertNoException nogc(cx);
JS_ASSERT(!*objp && !*pobjp && !*propp);
for (JSObject *scope = scopeChain; scope; scope = scope->enclosingScope()) {
if (scope->getOps()->lookupGeneric)
return false;
if (!LookupPropertyWithFlagsInline<NoGC>(cx, scope, NameToId(name),
cx->resolveFlags, pobjp, propp))
{
return false;
}
if (*propp) {
*objp = scope;
return true;
}
}
return true;
}
bool
js::LookupNameWithGlobalDefault(JSContext *cx, HandlePropertyName name, HandleObject scopeChain,
MutableHandleObject objp)
{
RootedId id(cx, NameToId(name));
RootedObject pobj(cx);
RootedShape prop(cx);
RootedObject scope(cx, scopeChain);
for (; !scope->is<GlobalObject>(); scope = scope->enclosingScope()) {
if (!JSObject::lookupGeneric(cx, scope, id, &pobj, &prop))
return false;
if (prop)
break;
}
objp.set(scope);
return true;
}
template <AllowGC allowGC>
bool
js::HasOwnProperty(JSContext *cx, LookupGenericOp lookup,
typename MaybeRooted<JSObject*, allowGC>::HandleType obj,
typename MaybeRooted<jsid, allowGC>::HandleType id,
typename MaybeRooted<JSObject*, allowGC>::MutableHandleType objp,
typename MaybeRooted<Shape*, allowGC>::MutableHandleType propp)
{
if (lookup) {
JSAutoResolveFlags rf(cx, 0);
if (!allowGC)
return false;
if (!lookup(cx,
MaybeRooted<JSObject*, allowGC>::toHandle(obj),
MaybeRooted<jsid, allowGC>::toHandle(id),
MaybeRooted<JSObject*, allowGC>::toMutableHandle(objp),
MaybeRooted<Shape*, allowGC>::toMutableHandle(propp)))
{
return false;
}
} else {
bool done;
if (!LookupOwnPropertyWithFlagsInline<allowGC>(cx, obj, id, 0, objp, propp, &done))
return false;
if (!done) {
objp.set(nullptr);
propp.set(nullptr);
return true;
}
}
if (!propp)
return true;
if (objp == obj)
return true;
JSObject *outer = nullptr;
if (JSObjectOp op = objp->getClass()->ext.outerObject) {
if (!allowGC)
return false;
RootedObject inner(cx, objp);
outer = op(cx, inner);
if (!outer)
return false;
}
if (outer != objp)
propp.set(nullptr);
return true;
}
template bool
js::HasOwnProperty<CanGC>(JSContext *cx, LookupGenericOp lookup,
HandleObject obj, HandleId id,
MutableHandleObject objp, MutableHandleShape propp);
template bool
js::HasOwnProperty<NoGC>(JSContext *cx, LookupGenericOp lookup,
JSObject *obj, jsid id,
FakeMutableHandle<JSObject*> objp, FakeMutableHandle<Shape*> propp);
template <AllowGC allowGC>
static JS_ALWAYS_INLINE bool
NativeGetInline(JSContext *cx,
typename MaybeRooted<JSObject*, allowGC>::HandleType obj,
typename MaybeRooted<JSObject*, allowGC>::HandleType receiver,
typename MaybeRooted<JSObject*, allowGC>::HandleType pobj,
typename MaybeRooted<Shape*, allowGC>::HandleType shape,
typename MaybeRooted<Value, allowGC>::MutableHandleType vp)
{
JS_ASSERT(pobj->isNative());
if (shape->hasSlot()) {
vp.set(pobj->nativeGetSlot(shape->slot()));
JS_ASSERT(!vp.isMagic());
JS_ASSERT_IF(!pobj->hasSingletonType() &&
!pobj->template is<ScopeObject>() &&
shape->hasDefaultGetter(),
js::types::TypeHasProperty(cx, pobj->type(), shape->propid(), vp));
} else {
vp.setUndefined();
}
if (shape->hasDefaultGetter())
return true;
{
jsbytecode *pc;
JSScript *script = cx->currentScript(&pc);
#ifdef JS_ION
if (script && script->hasBaselineScript()) {
switch (JSOp(*pc)) {
case JSOP_GETPROP:
case JSOP_CALLPROP:
case JSOP_LENGTH:
script->baselineScript()->noteAccessedGetter(cx, script->pcToOffset(pc));
break;
default:
break;
}
}
#endif
}
if (!allowGC)
return false;
if (!shape->get(cx,
MaybeRooted<JSObject*, allowGC>::toHandle(receiver),
MaybeRooted<JSObject*, allowGC>::toHandle(obj),
MaybeRooted<JSObject*, allowGC>::toHandle(pobj),
MaybeRooted<Value, allowGC>::toMutableHandle(vp)))
{
return false;
}
/* Update slotful shapes according to the value produced by the getter. */
if (shape->hasSlot() && pobj->nativeContains(cx, shape))
pobj->nativeSetSlot(shape->slot(), vp);
return true;
}
bool
js::NativeGet(JSContext *cx, Handle<JSObject*> obj, Handle<JSObject*> pobj, Handle<Shape*> shape,
MutableHandle<Value> vp)
{
return NativeGetInline<CanGC>(cx, obj, obj, pobj, shape, vp);
}
template <ExecutionMode mode>
bool
js::NativeSet(typename ExecutionModeTraits<mode>::ContextType cxArg,
Handle<JSObject*> obj, Handle<JSObject*> receiver,
HandleShape shape, bool strict, MutableHandleValue vp)
{
JS_ASSERT(cxArg->isThreadLocal(obj));
JS_ASSERT(obj->isNative());
if (shape->hasSlot()) {
/* If shape has a stub setter, just store vp. */
if (shape->hasDefaultSetter()) {
if (mode == ParallelExecution) {
if (!obj->nativeSetSlotIfHasType(shape, vp))
return false;
} else {
obj->nativeSetSlotWithType(cxArg->asExclusiveContext(), shape, vp);
}
return true;
}
}
if (mode == ParallelExecution)
return false;
JSContext *cx = cxArg->asJSContext();
if (!shape->hasSlot()) {
/*
* Allow API consumers to create shared properties with stub setters.
* Such properties effectively function as data descriptors which are
* not writable, so attempting to set such a property should do nothing
* or throw if we're in strict mode.
*/
if (!shape->hasGetterValue() && shape->hasDefaultSetter())
return js_ReportGetterOnlyAssignment(cx, strict);
}
RootedValue ovp(cx, vp);
uint32_t sample = cx->runtime()->propertyRemovals;
if (!shape->set(cx, obj, receiver, strict, vp))
return false;
/*
* Update any slot for the shape with the value produced by the setter,
* unless the setter deleted the shape.
*/
if (shape->hasSlot() &&
(JS_LIKELY(cx->runtime()->propertyRemovals == sample) ||
obj->nativeContains(cx, shape)))
{
obj->setSlot(shape->slot(), vp);
}
return true;
}
template bool
js::NativeSet<SequentialExecution>(JSContext *cx,
Handle<JSObject*> obj, Handle<JSObject*> receiver,
HandleShape shape, bool strict, MutableHandleValue vp);
template bool
js::NativeSet<ParallelExecution>(ForkJoinSlice *slice,
Handle<JSObject*> obj, Handle<JSObject*> receiver,
HandleShape shape, bool strict, MutableHandleValue vp);
template <AllowGC allowGC>
static JS_ALWAYS_INLINE bool
GetPropertyHelperInline(JSContext *cx,
typename MaybeRooted<JSObject*, allowGC>::HandleType obj,
typename MaybeRooted<JSObject*, allowGC>::HandleType receiver,
typename MaybeRooted<jsid, allowGC>::HandleType id,
typename MaybeRooted<Value, allowGC>::MutableHandleType vp)
{
/* This call site is hot -- use the always-inlined variant of LookupPropertyWithFlags(). */
typename MaybeRooted<JSObject*, allowGC>::RootType obj2(cx);
typename MaybeRooted<Shape*, allowGC>::RootType shape(cx);
if (!LookupPropertyWithFlagsInline<allowGC>(cx, obj, id, cx->resolveFlags, &obj2, &shape))
return false;
if (!shape) {
if (!allowGC)
return false;
vp.setUndefined();
if (!CallJSPropertyOp(cx, obj->getClass()->getProperty,
MaybeRooted<JSObject*, allowGC>::toHandle(obj),
MaybeRooted<jsid, allowGC>::toHandle(id),
MaybeRooted<Value, allowGC>::toMutableHandle(vp)))
{
return false;
}
/*
* Give a strict warning if foo.bar is evaluated by a script for an
* object foo with no property named 'bar'.
*/
if (vp.isUndefined()) {
jsbytecode *pc = nullptr;
RootedScript script(cx, cx->currentScript(&pc));
if (!pc)
return true;
JSOp op = (JSOp) *pc;
if (op == JSOP_GETXPROP) {
/* Undefined property during a name lookup, report an error. */
JSAutoByteString printable;
if (js_ValueToPrintable(cx, IdToValue(id), &printable))
js_ReportIsNotDefined(cx, printable.ptr());
return false;
}
/* Don't warn if extra warnings not enabled or for random getprop operations. */
if (!cx->options().extraWarnings() || (op != JSOP_GETPROP && op != JSOP_GETELEM))
return true;
/* Don't warn repeatedly for the same script. */
if (!script || script->warnedAboutUndefinedProp())
return true;
/*
* Don't warn in self-hosted code (where the further presence of
* JS::ContextOptions::werror() would result in impossible-to-avoid
* errors to entirely-innocent client code).
*/
if (script->selfHosted())
return true;
/* We may just be checking if that object has an iterator. */
if (JSID_IS_ATOM(id, cx->names().iteratorIntrinsic))
return true;
/* Do not warn about tests like (obj[prop] == undefined). */
if (cx->resolveFlags == RESOLVE_INFER) {
pc += js_CodeSpec[op].length;
if (Detecting(cx, script, pc))
return true;
}
unsigned flags = JSREPORT_WARNING | JSREPORT_STRICT;
script->setWarnedAboutUndefinedProp();
/* Ok, bad undefined property reference: whine about it. */
RootedValue val(cx, IdToValue(id));
if (!js_ReportValueErrorFlags(cx, flags, JSMSG_UNDEFINED_PROP,
JSDVG_IGNORE_STACK, val, js::NullPtr(),
nullptr, nullptr))
{
return false;
}
}
return true;
}
if (!obj2->isNative()) {
if (!allowGC)
return false;
HandleObject obj2Handle = MaybeRooted<JSObject*, allowGC>::toHandle(obj2);
HandleObject receiverHandle = MaybeRooted<JSObject*, allowGC>::toHandle(receiver);
HandleId idHandle = MaybeRooted<jsid, allowGC>::toHandle(id);
MutableHandleValue vpHandle = MaybeRooted<Value, allowGC>::toMutableHandle(vp);
return obj2->template is<ProxyObject>()
? Proxy::get(cx, obj2Handle, receiverHandle, idHandle, vpHandle)
: JSObject::getGeneric(cx, obj2Handle, obj2Handle, idHandle, vpHandle);
}
if (IsImplicitDenseElement(shape)) {
vp.set(obj2->getDenseElement(JSID_TO_INT(id)));
return true;
}
/* This call site is hot -- use the always-inlined variant of NativeGet(). */
if (!NativeGetInline<allowGC>(cx, obj, receiver, obj2, shape, vp))
return false;
return true;
}
bool
baseops::GetProperty(JSContext *cx, HandleObject obj, HandleObject receiver, HandleId id, MutableHandleValue vp)
{
/* This call site is hot -- use the always-inlined variant of GetPropertyHelper(). */
return GetPropertyHelperInline<CanGC>(cx, obj, receiver, id, vp);
}
bool
baseops::GetPropertyNoGC(JSContext *cx, JSObject *obj, JSObject *receiver, jsid id, Value *vp)
{
AutoAssertNoException nogc(cx);
return GetPropertyHelperInline<NoGC>(cx, obj, receiver, id, vp);
}
static JS_ALWAYS_INLINE bool
LookupPropertyPureInline(JSObject *obj, jsid id, JSObject **objp, Shape **propp)
{
if (!obj->isNative())
return false;
JSObject *current = obj;
while (true) {
/* Search for a native dense element or property. */
{
if (JSID_IS_INT(id) && current->containsDenseElement(JSID_TO_INT(id))) {
*objp = current;
MarkDenseElementFound<NoGC>(propp);
return true;
}
if (Shape *shape = current->nativeLookupPure(id)) {
*objp = current;
*propp = shape;
return true;
}
}
/* Fail if there's a resolve hook. */
if (current->getClass()->resolve != JS_ResolveStub)
return false;
JSObject *proto = current->getProto();
if (!proto)
break;
if (!proto->isNative())
return false;
current = proto;
}
*objp = nullptr;
*propp = nullptr;
return true;
}
static JS_ALWAYS_INLINE bool
NativeGetPureInline(JSObject *pobj, Shape *shape, Value *vp)
{
JS_ASSERT(pobj->isNative());
if (shape->hasSlot()) {
*vp = pobj->nativeGetSlot(shape->slot());
JS_ASSERT(!vp->isMagic());
} else {
vp->setUndefined();
}
/* Fail if we have a custom getter. */
return shape->hasDefaultGetter();
}
bool
js::LookupPropertyPure(JSObject *obj, jsid id, JSObject **objp, Shape **propp)
{
return LookupPropertyPureInline(obj, id, objp, propp);
}
static inline bool
IdIsLength(ThreadSafeContext *cx, jsid id)
{
return JSID_IS_ATOM(id) && cx->names().length == JSID_TO_ATOM(id);
}
/*
* A pure version of GetPropertyHelper that can be called from parallel code
* without locking. This code path cannot GC. This variant returns false
* whenever a side-effect might have occured in the effectful version. This
* includes, but is not limited to:
*
* - Any object in the lookup chain has a non-stub resolve hook.
* - Any object in the lookup chain is non-native.
* - The property has a getter.
*/
bool
js::GetPropertyPure(ThreadSafeContext *cx, JSObject *obj, jsid id, Value *vp)
{
/* Typed arrays are not native, so we fast-path them here. */
if (obj->is<TypedArrayObject>()) {
TypedArrayObject *tarr = &obj->as<TypedArrayObject>();
if (JSID_IS_INT(id)) {
uint32_t index = JSID_TO_INT(id);
if (index < tarr->length()) {
MutableHandleValue vpHandle = MutableHandleValue::fromMarkedLocation(vp);
tarr->copyTypedArrayElement(index, vpHandle);
return true;
}
return false;
}
if (IdIsLength(cx, id)) {
vp->setNumber(tarr->length());
return true;
}
return false;
}
/* Deal with native objects. */
JSObject *obj2;
Shape *shape;
if (!LookupPropertyPureInline(obj, id, &obj2, &shape))
return false;
if (!shape) {
/* Fail if we have a non-stub class op hooks. */
if (obj->getClass()->getProperty && obj->getClass()->getProperty != JS_PropertyStub)
return false;
if (obj->getOps()->getElement)
return false;
/* Vanilla native object, return undefined. */
vp->setUndefined();
return true;
}
if (IsImplicitDenseElement(shape)) {
*vp = obj2->getDenseElement(JSID_TO_INT(id));
return true;
}
/* Special case 'length' on Array. */
if (obj->is<ArrayObject>() && IdIsLength(cx, id)) {
vp->setNumber(obj->as<ArrayObject>().length());
return true;
}
return NativeGetPureInline(obj2, shape, vp);
}
static bool
JS_ALWAYS_INLINE
GetElementPure(ThreadSafeContext *cx, JSObject *obj, uint32_t index, Value *vp)
{
if (index <= JSID_INT_MAX)
return GetPropertyPure(cx, obj, INT_TO_JSID(index), vp);
return false;
}
/*
* A pure version of GetObjectElementOperation that can be called from
* parallel code without locking. This variant returns false whenever a
* side-effect might have occurred.
*/
bool
js::GetObjectElementOperationPure(ThreadSafeContext *cx, JSObject *obj, const Value &prop,
Value *vp)
{
uint32_t index;
if (IsDefinitelyIndex(prop, &index))
return GetElementPure(cx, obj, index, vp);
/* Atomizing the property value is effectful and not threadsafe. */
if (!prop.isString() || !prop.toString()->isAtom())
return false;
JSAtom *name = &prop.toString()->asAtom();
if (name->isIndex(&index))
return GetElementPure(cx, obj, index, vp);
return GetPropertyPure(cx, obj, NameToId(name->asPropertyName()), vp);
}
bool
baseops::GetElement(JSContext *cx, HandleObject obj, HandleObject receiver, uint32_t index,
MutableHandleValue vp)
{
RootedId id(cx);
if (!IndexToId(cx, index, &id))
return false;
/* This call site is hot -- use the always-inlined variant of js_GetPropertyHelper(). */
return GetPropertyHelperInline<CanGC>(cx, obj, receiver, id, vp);
}
static bool
MaybeReportUndeclaredVarAssignment(JSContext *cx, JSString *propname)
{
{
JSScript *script = cx->currentScript(nullptr, JSContext::ALLOW_CROSS_COMPARTMENT);
if (!script)
return true;
// If the code is not strict and extra warnings aren't enabled, then no
// check is needed.
if (!script->strict() && !cx->options().extraWarnings())
return true;
}
JSAutoByteString bytes(cx, propname);
return !!bytes &&
JS_ReportErrorFlagsAndNumber(cx,
(JSREPORT_WARNING | JSREPORT_STRICT
| JSREPORT_STRICT_MODE_ERROR),
js_GetErrorMessage, nullptr,
JSMSG_UNDECLARED_VAR, bytes.ptr());
}
bool
js::ReportIfUndeclaredVarAssignment(JSContext *cx, HandleString propname)
{
{
jsbytecode *pc;
JSScript *script = cx->currentScript(&pc, JSContext::ALLOW_CROSS_COMPARTMENT);
if (!script)
return true;
// If the code is not strict and extra warnings aren't enabled, then no
// check is needed.
if (!script->strict() && !cx->options().extraWarnings())
return true;
/*
* We only need to check for bare name mutations: we shouldn't be
* warning, or throwing, or whatever, if we're not doing a variable
* access.
*
* TryConvertToGname in frontend/BytecodeEmitter.cpp checks for rather
* more opcodes when it does, in the normal course of events, what this
* method does in the abnormal course of events. Because we're called
* in narrower circumstances, we only need check two. We don't need to
* check for the increment/decrement opcodes because they're no-ops:
* the actual semantics are implemented by desugaring. And we don't
* need to check name-access because this method is only supposed to be
* called in assignment contexts.
*/
MOZ_ASSERT(*pc != JSOP_NAME);
MOZ_ASSERT(*pc != JSOP_GETGNAME);
if (*pc != JSOP_SETNAME && *pc != JSOP_SETGNAME)
return true;
}
JSAutoByteString bytes(cx, propname);
return !!bytes &&
JS_ReportErrorFlagsAndNumber(cx,
JSREPORT_WARNING | JSREPORT_STRICT |
JSREPORT_STRICT_MODE_ERROR,
js_GetErrorMessage, nullptr,
JSMSG_UNDECLARED_VAR, bytes.ptr());
}
bool
JSObject::reportReadOnly(ThreadSafeContext *cxArg, jsid id, unsigned report)
{
if (cxArg->isForkJoinSlice())
return cxArg->asForkJoinSlice()->reportError(ParallelBailoutUnsupportedVM, report);
if (!cxArg->isJSContext())
return true;
JSContext *cx = cxArg->asJSContext();
RootedValue val(cx, IdToValue(id));
return js_ReportValueErrorFlags(cx, report, JSMSG_READ_ONLY,
JSDVG_IGNORE_STACK, val, js::NullPtr(),
nullptr, nullptr);
}
bool
JSObject::reportNotConfigurable(ThreadSafeContext *cxArg, jsid id, unsigned report)
{
if (cxArg->isForkJoinSlice())
return cxArg->asForkJoinSlice()->reportError(ParallelBailoutUnsupportedVM, report);
if (!cxArg->isJSContext())
return true;
JSContext *cx = cxArg->asJSContext();
RootedValue val(cx, IdToValue(id));
return js_ReportValueErrorFlags(cx, report, JSMSG_CANT_DELETE,
JSDVG_IGNORE_STACK, val, js::NullPtr(),
nullptr, nullptr);
}
bool
JSObject::reportNotExtensible(ThreadSafeContext *cxArg, unsigned report)
{
if (cxArg->isForkJoinSlice())
return cxArg->asForkJoinSlice()->reportError(ParallelBailoutUnsupportedVM, report);
if (!cxArg->isJSContext())
return true;
JSContext *cx = cxArg->asJSContext();
RootedValue val(cx, ObjectValue(*this));
return js_ReportValueErrorFlags(cx, report, JSMSG_OBJECT_NOT_EXTENSIBLE,
JSDVG_IGNORE_STACK, val, js::NullPtr(),
nullptr, nullptr);
}
bool
JSObject::callMethod(JSContext *cx, HandleId id, unsigned argc, Value *argv, MutableHandleValue vp)
{
RootedValue fval(cx);
RootedObject obj(cx, this);
if (!JSObject::getGeneric(cx, obj, obj, id, &fval))
return false;
return Invoke(cx, ObjectValue(*obj), fval, argc, argv, vp);
}
template <ExecutionMode mode>
bool
baseops::SetPropertyHelper(typename ExecutionModeTraits<mode>::ContextType cxArg,
HandleObject obj, HandleObject receiver, HandleId id,
unsigned defineHow, MutableHandleValue vp, bool strict)
{
JS_ASSERT(cxArg->isThreadLocal(obj));
JS_ASSERT((defineHow & ~DNP_UNQUALIFIED) == 0);
if (JS_UNLIKELY(obj->watched())) {
if (mode == ParallelExecution)
return false;
/* Fire watchpoints, if any. */
JSContext *cx = cxArg->asJSContext();
WatchpointMap *wpmap = cx->compartment()->watchpointMap;
if (wpmap && !wpmap->triggerWatchpoint(cx, obj, id, vp))
return false;
}
RootedObject pobj(cxArg);
RootedShape shape(cxArg);
if (mode == ParallelExecution) {
if (!LookupPropertyPure(obj, id, pobj.address(), shape.address()))
return false;
} else {
JSContext *cx = cxArg->asJSContext();
if (!LookupPropertyWithFlags(cx, obj, id, cx->resolveFlags, &pobj, &shape))
return false;
}
if (shape) {
if (!pobj->isNative()) {
if (pobj->is<ProxyObject>()) {
if (mode == ParallelExecution)
return false;
JSContext *cx = cxArg->asJSContext();
Rooted<PropertyDescriptor> pd(cx);
if (!Proxy::getPropertyDescriptor(cx, pobj, id, &pd, JSRESOLVE_ASSIGNING))
return false;
if ((pd.attributes() & (JSPROP_SHARED | JSPROP_SHADOWABLE)) == JSPROP_SHARED) {
return !pd.setter() ||
CallSetter(cx, receiver, id, pd.setter(), pd.attributes(),
pd.shortid(), strict, vp);
}
if (pd.isReadonly()) {
if (strict)
return JSObject::reportReadOnly(cx, id, JSREPORT_ERROR);
if (cx->options().extraWarnings())
return JSObject::reportReadOnly(cx, id, JSREPORT_STRICT | JSREPORT_WARNING);
return true;
}
}
shape = nullptr;
}
} else {
/* We should never add properties to lexical blocks. */
JS_ASSERT(!obj->is<BlockObject>());
if (obj->is<GlobalObject>() && (defineHow & DNP_UNQUALIFIED)) {
if (mode == ParallelExecution)
return false;
if (!MaybeReportUndeclaredVarAssignment(cxArg->asJSContext(), JSID_TO_STRING(id)))
return false;
}
}
/*
* Now either shape is null, meaning id was not found in obj or one of its
* prototypes; or shape is non-null, meaning id was found directly in pobj.
*/
unsigned attrs = JSPROP_ENUMERATE;
unsigned flags = 0;
int shortid = 0;
const Class *clasp = obj->getClass();
PropertyOp getter = clasp->getProperty;
StrictPropertyOp setter = clasp->setProperty;
if (IsImplicitDenseElement(shape)) {
/* ES5 8.12.4 [[Put]] step 2, for a dense data property on pobj. */
if (pobj != obj)
shape = nullptr;
} else if (shape) {
/* ES5 8.12.4 [[Put]] step 2. */
if (shape->isAccessorDescriptor()) {
if (shape->hasDefaultSetter()) {
/* Bail out of parallel execution if we are strict to throw. */
if (mode == ParallelExecution)
return !strict;
return js_ReportGetterOnlyAssignment(cxArg->asJSContext(), strict);
}
} else {
JS_ASSERT(shape->isDataDescriptor());
if (!shape->writable()) {
/*
* Error in strict mode code, warn with extra warnings
* options, otherwise do nothing.
*
* Bail out of parallel execution if we are strict to throw.
*/
if (mode == ParallelExecution)
return !strict;
JSContext *cx = cxArg->asJSContext();
if (strict)
return JSObject::reportReadOnly(cx, id, JSREPORT_ERROR);
if (cx->options().extraWarnings())
return JSObject::reportReadOnly(cx, id, JSREPORT_STRICT | JSREPORT_WARNING);
return true;
}
}
attrs = shape->attributes();
if (pobj != obj) {
/*
* We found id in a prototype object: prepare to share or shadow.
*/
if (!shape->shadowable()) {
if (shape->hasDefaultSetter() && !shape->hasGetterValue())
return true;
if (mode == ParallelExecution)
return false;
return shape->set(cxArg->asJSContext(), obj, receiver, strict, vp);
}
/*
* Preserve attrs except JSPROP_SHARED, getter, and setter when
* shadowing any property that has no slot (is shared). We must
* clear the shared attribute for the shadowing shape so that the
* property in obj that it defines has a slot to retain the value
* being set, in case the setter simply cannot operate on instances
* of obj's class by storing the value in some class-specific
* location.
*
* A subset of slotless shared properties is the set of properties
* with shortids, which must be preserved too. An old API requires
* that the property's getter and setter receive the shortid, not
* id, when they are called on the shadowing property that we are
* about to create in obj.
*/
if (!shape->hasSlot()) {
if (shape->hasShortID()) {
flags = Shape::HAS_SHORTID;
shortid = shape->shortid();
}
attrs &= ~JSPROP_SHARED;
getter = shape->getter();
setter = shape->setter();
} else {
/* Restore attrs to the ECMA default for new properties. */
attrs = JSPROP_ENUMERATE;
}
/*
* Forget we found the proto-property now that we've copied any
* needed member values.
*/
shape = nullptr;
}
}
if (IsImplicitDenseElement(shape)) {
uint32_t index = JSID_TO_INT(id);
bool definesPast;
if (!WouldDefinePastNonwritableLength(cxArg, obj, index, strict, &definesPast))
return false;
if (definesPast) {
/* Bail out of parallel execution if we are strict to throw. */
if (mode == ParallelExecution)
return !strict;
return true;
}
if (mode == ParallelExecution)
obj->setDenseElementIfHasType(index, vp);
else
obj->setDenseElementWithType(cxArg->asJSContext(), index, vp);
return true;
}
if (obj->is<ArrayObject>() && id == NameToId(cxArg->names().length)) {
Rooted<ArrayObject*> arr(cxArg, &obj->as<ArrayObject>());
return ArraySetLength<mode>(cxArg, arr, id, attrs, vp, strict);
}
if (!shape) {
bool extensible;
if (mode == ParallelExecution) {
if (obj->is<ProxyObject>())
return false;
extensible = obj->nonProxyIsExtensible();
} else {
if (!JSObject::isExtensible(cxArg->asJSContext(), obj, &extensible))
return false;
}
if (!extensible) {
/* Error in strict mode code, warn with extra warnings option, otherwise do nothing. */
if (strict)
return obj->reportNotExtensible(cxArg);
if (mode == SequentialExecution && cxArg->asJSContext()->options().extraWarnings())
return obj->reportNotExtensible(cxArg, JSREPORT_STRICT | JSREPORT_WARNING);
return true;
}
if (mode == ParallelExecution) {
if (obj->isDelegate())
return false;
if (getter != JS_PropertyStub || !HasTypePropertyId(obj, id, vp))
return false;
} else {
JSContext *cx = cxArg->asJSContext();
/* Purge the property cache of now-shadowed id in obj's scope chain. */
if (!PurgeScopeChain(cx, obj, id))
return false;
}
return DefinePropertyOrElement<mode>(cxArg, obj, id, getter, setter,
attrs, flags, shortid, vp, true, strict);
}
return NativeSet<mode>(cxArg, obj, receiver, shape, strict, vp);
}
template bool
baseops::SetPropertyHelper<SequentialExecution>(JSContext *cx, HandleObject obj,
HandleObject receiver,
HandleId id, unsigned defineHow,
MutableHandleValue vp, bool strict);
template bool
baseops::SetPropertyHelper<ParallelExecution>(ForkJoinSlice *slice, HandleObject obj,
HandleObject receiver,
HandleId id, unsigned defineHow,
MutableHandleValue vp, bool strict);
bool
baseops::SetElementHelper(JSContext *cx, HandleObject obj, HandleObject receiver, uint32_t index,
unsigned defineHow, MutableHandleValue vp, bool strict)
{
RootedId id(cx);
if (!IndexToId(cx, index, &id))
return false;
return baseops::SetPropertyHelper<SequentialExecution>(cx, obj, receiver, id, defineHow, vp,
strict);
}
bool
baseops::GetAttributes(JSContext *cx, HandleObject obj, HandleId id, unsigned *attrsp)
{
RootedObject nobj(cx);
RootedShape shape(cx);
if (!baseops::LookupProperty<CanGC>(cx, obj, id, &nobj, &shape))
return false;
if (!shape) {
*attrsp = 0;
return true;
}
if (!nobj->isNative())
return JSObject::getGenericAttributes(cx, nobj, id, attrsp);
*attrsp = GetShapeAttributes(shape);
return true;
}
bool
baseops::SetAttributes(JSContext *cx, HandleObject obj, HandleId id, unsigned *attrsp)
{
RootedObject nobj(cx);
RootedShape shape(cx);
if (!baseops::LookupProperty<CanGC>(cx, obj, id, &nobj, &shape))
return false;
if (!shape)
return true;
if (nobj->isNative() && IsImplicitDenseElement(shape)) {
if (!JSObject::sparsifyDenseElement(cx, nobj, JSID_TO_INT(id)))
return false;
shape = obj->nativeLookup(cx, id);
}
if (nobj->isNative()) {
if (!JSObject::changePropertyAttributes(cx, nobj, shape, *attrsp))
return false;
if (*attrsp & JSPROP_READONLY)
MarkTypePropertyConfigured(cx, obj, id);
return true;
} else {
return JSObject::setGenericAttributes(cx, nobj, id, attrsp);
}
}
bool
baseops::DeleteGeneric(JSContext *cx, HandleObject obj, HandleId id, bool *succeeded)
{
RootedObject proto(cx);
RootedShape shape(cx);
if (!baseops::LookupProperty<CanGC>(cx, obj, id, &proto, &shape))
return false;
if (!shape || proto != obj) {
/*
* If no property, or the property comes from a prototype, call the
* class's delProperty hook, passing succeeded as the result parameter.
*/
return CallJSDeletePropertyOp(cx, obj->getClass()->delProperty, obj, id, succeeded);
}
GCPoke(cx->runtime());
if (IsImplicitDenseElement(shape)) {
if (!CallJSDeletePropertyOp(cx, obj->getClass()->delProperty, obj, id, succeeded))
return false;
if (!succeeded)
return true;
obj->setDenseElementHole(cx, JSID_TO_INT(id));
return js_SuppressDeletedProperty(cx, obj, id);
}
if (!shape->configurable()) {
*succeeded = false;
return true;
}
RootedId userid(cx);
if (!shape->getUserId(cx, &userid))
return false;
if (!CallJSDeletePropertyOp(cx, obj->getClass()->delProperty, obj, userid, succeeded))
return false;
if (!succeeded)
return true;
return obj->removeProperty(cx, id) && js_SuppressDeletedProperty(cx, obj, id);
}
bool
baseops::DeleteProperty(JSContext *cx, HandleObject obj, HandlePropertyName name,
bool *succeeded)
{
Rooted<jsid> id(cx, NameToId(name));
return baseops::DeleteGeneric(cx, obj, id, succeeded);
}
bool
baseops::DeleteElement(JSContext *cx, HandleObject obj, uint32_t index, bool *succeeded)
{
RootedId id(cx);
if (!IndexToId(cx, index, &id))
return false;
return baseops::DeleteGeneric(cx, obj, id, succeeded);
}
bool
baseops::DeleteSpecial(JSContext *cx, HandleObject obj, HandleSpecialId sid, bool *succeeded)
{
Rooted<jsid> id(cx, SPECIALID_TO_JSID(sid));
return baseops::DeleteGeneric(cx, obj, id, succeeded);
}
bool
js::WatchGuts(JSContext *cx, JS::HandleObject origObj, JS::HandleId id, JS::HandleObject callable)
{
RootedObject obj(cx, GetInnerObject(cx, origObj));
if (origObj != obj) {
// If by unwrapping and innerizing, we changed the object, check again
// to make sure that we're allowed to set a watch point.
RootedValue v(cx);
unsigned attrs;
if (!CheckAccess(cx, obj, id, JSACC_WATCH, &v, &attrs))
return false;
}
if (obj->isNative()) {
// Use sparse indexes for watched objects, as dense elements can be
// written to without checking the watchpoint map.
if (!JSObject::sparsifyDenseElements(cx, obj))
return false;
types::MarkTypePropertyConfigured(cx, obj, id);
}
WatchpointMap *wpmap = cx->compartment()->watchpointMap;
if (!wpmap) {
wpmap = cx->runtime()->new_<WatchpointMap>();
if (!wpmap || !wpmap->init()) {
js_ReportOutOfMemory(cx);
return false;
}
cx->compartment()->watchpointMap = wpmap;
}
return wpmap->watch(cx, obj, id, js::WatchHandler, callable);
}
bool
baseops::Watch(JSContext *cx, JS::HandleObject obj, JS::HandleId id, JS::HandleObject callable)
{
if (!obj->isNative()) {
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_CANT_WATCH,
obj->getClass()->name);
return false;
}
return WatchGuts(cx, obj, id, callable);
}
bool
js::UnwatchGuts(JSContext *cx, JS::HandleObject origObj, JS::HandleId id)
{
// Looking in the map for an unsupported object will never hit, so we don't
// need to check for nativeness or watchable-ness here.
RootedObject obj(cx, GetInnerObject(cx, origObj));
if (WatchpointMap *wpmap = cx->compartment()->watchpointMap)
wpmap->unwatch(obj, id, nullptr, nullptr);
return true;
}
bool
baseops::Unwatch(JSContext *cx, JS::HandleObject obj, JS::HandleId id)
{
return UnwatchGuts(cx, obj, id);
}
bool
js::HasDataProperty(JSContext *cx, JSObject *obj, jsid id, Value *vp)
{
if (JSID_IS_INT(id) && obj->containsDenseElement(JSID_TO_INT(id))) {
*vp = obj->getDenseElement(JSID_TO_INT(id));
return true;
}
if (Shape *shape = obj->nativeLookup(cx, id)) {
if (shape->hasDefaultGetter() && shape->hasSlot()) {
*vp = obj->nativeGetSlot(shape->slot());
return true;
}
}
return false;
}
/*
* Gets |obj[id]|. If that value's not callable, returns true and stores a
* non-primitive value in *vp. If it's callable, calls it with no arguments
* and |obj| as |this|, returning the result in *vp.
*
* This is a mini-abstraction for ES5 8.12.8 [[DefaultValue]], either steps 1-2
* or steps 3-4.
*/
static bool
MaybeCallMethod(JSContext *cx, HandleObject obj, HandleId id, MutableHandleValue vp)
{
if (!JSObject::getGeneric(cx, obj, obj, id, vp))
return false;
if (!js_IsCallable(vp)) {
vp.setObject(*obj);
return true;
}
return Invoke(cx, ObjectValue(*obj), vp, 0, nullptr, vp);
}
JS_FRIEND_API(bool)
js::DefaultValue(JSContext *cx, HandleObject obj, JSType hint, MutableHandleValue vp)
{
JS_ASSERT(hint == JSTYPE_NUMBER || hint == JSTYPE_STRING || hint == JSTYPE_VOID);
Rooted<jsid> id(cx);
const Class *clasp = obj->getClass();
if (hint == JSTYPE_STRING) {
id = NameToId(cx->names().toString);
/* Optimize (new String(...)).toString(). */
if (clasp == &StringObject::class_) {
if (ClassMethodIsNative(cx, obj, &StringObject::class_, id, js_str_toString)) {
vp.setString(obj->as<StringObject>().unbox());
return true;
}
}
if (!MaybeCallMethod(cx, obj, id, vp))
return false;
if (vp.isPrimitive())
return true;
id = NameToId(cx->names().valueOf);
if (!MaybeCallMethod(cx, obj, id, vp))
return false;
if (vp.isPrimitive())
return true;
} else {
/* Optimize new String(...).valueOf(). */
if (clasp == &StringObject::class_) {
id = NameToId(cx->names().valueOf);
if (ClassMethodIsNative(cx, obj, &StringObject::class_, id, js_str_toString)) {
vp.setString(obj->as<StringObject>().unbox());
return true;
}
}
/* Optimize new Number(...).valueOf(). */
if (clasp == &NumberObject::class_) {
id = NameToId(cx->names().valueOf);
if (ClassMethodIsNative(cx, obj, &NumberObject::class_, id, js_num_valueOf)) {
vp.setNumber(obj->as<NumberObject>().unbox());
return true;
}
}
id = NameToId(cx->names().valueOf);
if (!MaybeCallMethod(cx, obj, id, vp))
return false;
if (vp.isPrimitive())
return true;
id = NameToId(cx->names().toString);
if (!MaybeCallMethod(cx, obj, id, vp))
return false;
if (vp.isPrimitive())
return true;
}
/* Avoid recursive death when decompiling in js_ReportValueError. */
RootedString str(cx);
if (hint == JSTYPE_STRING) {
str = JS_InternString(cx, clasp->name);
if (!str)
return false;
} else {
str = nullptr;
}
RootedValue val(cx, ObjectValue(*obj));
js_ReportValueError2(cx, JSMSG_CANT_CONVERT_TO, JSDVG_SEARCH_STACK, val, str,
(hint == JSTYPE_VOID) ? "primitive type" : TypeStrings[hint]);
return false;
}
JS_FRIEND_API(bool)
JS_EnumerateState(JSContext *cx, HandleObject obj, JSIterateOp enum_op,
MutableHandleValue statep, JS::MutableHandleId idp)
{
/* If the class has a custom JSCLASS_NEW_ENUMERATE hook, call it. */
const Class *clasp = obj->getClass();
JSEnumerateOp enumerate = clasp->enumerate;
if (clasp->flags & JSCLASS_NEW_ENUMERATE) {
JS_ASSERT(enumerate != JS_EnumerateStub);
return ((JSNewEnumerateOp) enumerate)(cx, obj, enum_op, statep, idp);
}
if (!enumerate(cx, obj))
return false;
/* Tell InitNativeIterator to treat us like a native object. */
JS_ASSERT(enum_op == JSENUMERATE_INIT || enum_op == JSENUMERATE_INIT_ALL);
statep.setMagic(JS_NATIVE_ENUMERATE);
return true;
}
bool
js::CheckAccess(JSContext *cx, JSObject *obj_, HandleId id, JSAccessMode mode,
MutableHandleValue vp, unsigned *attrsp)
{
bool writing;
RootedObject obj(cx, obj_), pobj(cx);
while (JS_UNLIKELY(obj->is<WithObject>()))
obj = obj->getProto();
writing = (mode & JSACC_WRITE) != 0;
switch (mode & JSACC_TYPEMASK) {
case JSACC_PROTO:
pobj = obj;
if (!writing) {
RootedObject proto(cx);
if (!JSObject::getProto(cx, obj, &proto))
return false;
vp.setObjectOrNull(proto);
}
*attrsp = JSPROP_PERMANENT;
break;
default:
RootedShape shape(cx);
if (!JSObject::lookupGeneric(cx, obj, id, &pobj, &shape))
return false;
if (!shape) {
if (!writing)
vp.setUndefined();
*attrsp = 0;
pobj = obj;
break;
}
if (!pobj->isNative()) {
if (!writing) {
vp.setUndefined();
*attrsp = 0;
}
break;
}
*attrsp = GetShapeAttributes(shape);
if (!writing) {
if (IsImplicitDenseElement(shape)) {
vp.set(pobj->getDenseElement(JSID_TO_INT(id)));
} else {
if (shape->hasSlot())
vp.set(pobj->nativeGetSlot(shape->slot()));
else
vp.setUndefined();
}
}
}
JS_ASSERT_IF(*attrsp & JSPROP_READONLY, !(*attrsp & (JSPROP_GETTER | JSPROP_SETTER)));
/*
* If obj's class has a stub (null) checkAccess hook, use the per-runtime
* checkObjectAccess callback, if configured.
*
* We don't want to require all classes to supply a checkAccess hook; we
* need that hook only for certain classes used when precompiling scripts
* and functions ("brutal sharing"). But for general safety of built-in
* magic properties like __proto__, we route all access checks, even for
* classes that stub out checkAccess, through the global checkObjectAccess
* hook. This covers precompilation-based sharing and (possibly
* unintended) runtime sharing across trust boundaries.
*/
JSCheckAccessOp check = pobj->getClass()->checkAccess;
if (!check)
check = cx->runtime()->securityCallbacks->checkObjectAccess;
return !check || check(cx, pobj, id, mode, vp);
}
bool
js::IsDelegate(JSContext *cx, HandleObject obj, const js::Value &v, bool *result)
{
if (v.isPrimitive()) {
*result = false;
return true;
}
RootedObject obj2(cx, &v.toObject());
for (;;) {
if (!JSObject::getProto(cx, obj2, &obj2))
return false;
if (!obj2) {
*result = false;
return true;
}
if (obj2 == obj) {
*result = true;
return true;
}
}
}
JSObject *
js::GetClassPrototypePure(GlobalObject *global, JSProtoKey protoKey)
{
JS_ASSERT(JSProto_Null <= protoKey);
JS_ASSERT(protoKey < JSProto_LIMIT);
if (protoKey != JSProto_Null) {
const Value &v = global->getPrototype(protoKey);
if (v.isObject())
return &v.toObject();
}
return nullptr;
}
/*
* The first part of this function has been hand-expanded and optimized into
* NewBuiltinClassInstance in jsobjinlines.h.
*/
bool
js_GetClassPrototype(ExclusiveContext *cx, JSProtoKey protoKey,
MutableHandleObject protop, const Class *clasp)
{
if (JSObject *proto = GetClassPrototypePure(cx->global(), protoKey)) {
protop.set(proto);
return true;
}
RootedValue v(cx);
if (!js_FindClassObject(cx, protoKey, &v, clasp))
return false;
if (IsFunctionObject(v)) {
RootedObject ctor(cx, &v.get().toObject());
if (cx->isJSContext()) {
if (!JSObject::getProperty(cx->asJSContext(),
ctor, ctor, cx->names().prototype, &v))
{
return false;
}
} else {
Shape *shape = ctor->nativeLookup(cx, cx->names().prototype);
if (!shape || !NativeGetPureInline(ctor, shape, v.address()))
return false;
}
}
protop.set(v.get().isObject() ? &v.get().toObject() : nullptr);
return true;
}
JSObject *
js::PrimitiveToObject(JSContext *cx, const Value &v)
{
if (v.isString()) {
Rooted<JSString*> str(cx, v.toString());
return StringObject::create(cx, str);
}
if (v.isNumber())
return NumberObject::create(cx, v.toNumber());
JS_ASSERT(v.isBoolean());
return BooleanObject::create(cx, v.toBoolean());
}
/* Callers must handle the already-object case . */
JSObject *
js::ToObjectSlow(JSContext *cx, HandleValue val, bool reportScanStack)
{
JS_ASSERT(!val.isMagic());
JS_ASSERT(!val.isObject());
if (val.isNullOrUndefined()) {
if (reportScanStack) {
js_ReportIsNullOrUndefined(cx, JSDVG_SEARCH_STACK, val, NullPtr());
} else {
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_CANT_CONVERT_TO,
val.isNull() ? "null" : "undefined", "object");
}
return nullptr;
}
return PrimitiveToObject(cx, val);
}
void
js_GetObjectSlotName(JSTracer *trc, char *buf, size_t bufsize)
{
JS_ASSERT(trc->debugPrinter == js_GetObjectSlotName);
JSObject *obj = (JSObject *)trc->debugPrintArg;
uint32_t slot = uint32_t(trc->debugPrintIndex);
Shape *shape;
if (obj->isNative()) {
shape = obj->lastProperty();
while (shape && (!shape->hasSlot() || shape->slot() != slot))
shape = shape->previous();
} else {
shape = nullptr;
}
if (!shape) {
const char *slotname = nullptr;
if (obj->is<GlobalObject>()) {
#define TEST_SLOT_MATCHES_PROTOTYPE(name,code,init,clasp) \
if ((code) == slot) { slotname = js_##name##_str; goto found; }
JS_FOR_EACH_PROTOTYPE(TEST_SLOT_MATCHES_PROTOTYPE)
#undef TEST_SLOT_MATCHES_PROTOTYPE
}
found:
if (slotname)
JS_snprintf(buf, bufsize, "CLASS_OBJECT(%s)", slotname);
else
JS_snprintf(buf, bufsize, "**UNKNOWN SLOT %ld**", (long)slot);
} else {
jsid propid = shape->propid();
if (JSID_IS_INT(propid)) {
JS_snprintf(buf, bufsize, "%ld", (long)JSID_TO_INT(propid));
} else if (JSID_IS_ATOM(propid)) {
PutEscapedString(buf, bufsize, JSID_TO_ATOM(propid), 0);
} else {
JS_snprintf(buf, bufsize, "**FINALIZED ATOM KEY**");
}
}
}
bool
js_ReportGetterOnlyAssignment(JSContext *cx, bool strict)
{
return JS_ReportErrorFlagsAndNumber(cx,
strict
? JSREPORT_ERROR
: JSREPORT_WARNING | JSREPORT_STRICT,
js_GetErrorMessage, nullptr,
JSMSG_GETTER_ONLY);
}
JS_FRIEND_API(bool)
js_GetterOnlyPropertyStub(JSContext *cx, HandleObject obj, HandleId id, bool strict,
MutableHandleValue vp)
{
JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_GETTER_ONLY);
return false;
}
#ifdef DEBUG
/*
* Routines to print out values during debugging. These are FRIEND_API to help
* the debugger find them and to support temporarily hacking js_Dump* calls
* into other code.
*/
static void
dumpValue(const Value &v)
{
if (v.isNull())
fprintf(stderr, "null");
else if (v.isUndefined())
fprintf(stderr, "undefined");
else if (v.isInt32())
fprintf(stderr, "%d", v.toInt32());
else if (v.isDouble())
fprintf(stderr, "%g", v.toDouble());
else if (v.isString())
v.toString()->dump();
else if (v.isObject() && v.toObject().is<JSFunction>()) {
JSFunction *fun = &v.toObject().as<JSFunction>();
if (fun->displayAtom()) {
fputs("<function ", stderr);
FileEscapedString(stderr, fun->displayAtom(), 0);
} else {
fputs("<unnamed function", stderr);
}
if (fun->hasScript()) {
JSScript *script = fun->nonLazyScript();
fprintf(stderr, " (%s:%d)",
script->filename() ? script->filename() : "", (int) script->lineno());
}
fprintf(stderr, " at %p>", (void *) fun);
} else if (v.isObject()) {
JSObject *obj = &v.toObject();
const Class *clasp = obj->getClass();
fprintf(stderr, "<%s%s at %p>",
clasp->name,
(clasp == &JSObject::class_) ? "" : " object",
(void *) obj);
} else if (v.isBoolean()) {
if (v.toBoolean())
fprintf(stderr, "true");
else
fprintf(stderr, "false");
} else if (v.isMagic()) {
fprintf(stderr, "<invalid");
#ifdef DEBUG
switch (v.whyMagic()) {
case JS_ELEMENTS_HOLE: fprintf(stderr, " elements hole"); break;
case JS_NATIVE_ENUMERATE: fprintf(stderr, " native enumeration"); break;
case JS_NO_ITER_VALUE: fprintf(stderr, " no iter value"); break;
case JS_GENERATOR_CLOSING: fprintf(stderr, " generator closing"); break;
default: fprintf(stderr, " ?!"); break;
}
#endif
fprintf(stderr, ">");
} else {
fprintf(stderr, "unexpected value");
}
}
JS_FRIEND_API(void)
js_DumpValue(const Value &val)
{
dumpValue(val);
fputc('\n', stderr);
}
JS_FRIEND_API(void)
js_DumpId(jsid id)
{
fprintf(stderr, "jsid %p = ", (void *) JSID_BITS(id));
dumpValue(IdToValue(id));
fputc('\n', stderr);
}
static void
DumpProperty(JSObject *obj, Shape &shape)
{
jsid id = shape.propid();
uint8_t attrs = shape.attributes();
fprintf(stderr, " ((JSShape *) %p) ", (void *) &shape);
if (attrs & JSPROP_ENUMERATE) fprintf(stderr, "enumerate ");
if (attrs & JSPROP_READONLY) fprintf(stderr, "readonly ");
if (attrs & JSPROP_PERMANENT) fprintf(stderr, "permanent ");
if (attrs & JSPROP_SHARED) fprintf(stderr, "shared ");
if (shape.hasGetterValue())
fprintf(stderr, "getterValue=%p ", (void *) shape.getterObject());
else if (!shape.hasDefaultGetter())
fprintf(stderr, "getterOp=%p ", JS_FUNC_TO_DATA_PTR(void *, shape.getterOp()));
if (shape.hasSetterValue())
fprintf(stderr, "setterValue=%p ", (void *) shape.setterObject());
else if (!shape.hasDefaultSetter())
fprintf(stderr, "setterOp=%p ", JS_FUNC_TO_DATA_PTR(void *, shape.setterOp()));
if (JSID_IS_ATOM(id))
JSID_TO_STRING(id)->dump();
else if (JSID_IS_INT(id))
fprintf(stderr, "%d", (int) JSID_TO_INT(id));
else
fprintf(stderr, "unknown jsid %p", (void *) JSID_BITS(id));
uint32_t slot = shape.hasSlot() ? shape.maybeSlot() : SHAPE_INVALID_SLOT;
fprintf(stderr, ": slot %d", slot);
if (shape.hasSlot()) {
fprintf(stderr, " = ");
dumpValue(obj->getSlot(slot));
} else if (slot != SHAPE_INVALID_SLOT) {
fprintf(stderr, " (INVALID!)");
}
fprintf(stderr, "\n");
}
bool
JSObject::uninlinedIsProxy() const
{
AutoThreadSafeAccess ts0(this);
AutoThreadSafeAccess ts1(type_);
return is<ProxyObject>();
}
void
JSObject::dump()
{
JSObject *obj = this;
fprintf(stderr, "object %p\n", (void *) obj);
const Class *clasp = obj->getClass();
fprintf(stderr, "class %p %s\n", (const void *)clasp, clasp->name);
fprintf(stderr, "flags:");
if (obj->isDelegate()) fprintf(stderr, " delegate");
if (!obj->is<ProxyObject>() && !obj->nonProxyIsExtensible()) fprintf(stderr, " not_extensible");
if (obj->isIndexed()) fprintf(stderr, " indexed");
if (obj->isNative()) {
if (obj->inDictionaryMode())
fprintf(stderr, " inDictionaryMode");
if (obj->hasShapeTable())
fprintf(stderr, " hasShapeTable");
}
fprintf(stderr, "\n");
if (obj->isNative()) {
uint32_t slots = obj->getDenseInitializedLength();
if (slots) {
fprintf(stderr, "elements\n");
for (uint32_t i = 0; i < slots; i++) {
fprintf(stderr, " %3d: ", i);
dumpValue(obj->getDenseElement(i));
fprintf(stderr, "\n");
fflush(stderr);
}
}
}
fprintf(stderr, "proto ");
TaggedProto proto = obj->getTaggedProto();
if (proto.isLazy())
fprintf(stderr, "<lazy>");
else
dumpValue(ObjectOrNullValue(proto.toObjectOrNull()));
fputc('\n', stderr);
fprintf(stderr, "parent ");
dumpValue(ObjectOrNullValue(obj->getParent()));
fputc('\n', stderr);
if (clasp->flags & JSCLASS_HAS_PRIVATE)
fprintf(stderr, "private %p\n", obj->getPrivate());
if (!obj->isNative())
fprintf(stderr, "not native\n");
uint32_t reservedEnd = JSCLASS_RESERVED_SLOTS(clasp);
uint32_t slots = obj->slotSpan();
uint32_t stop = obj->isNative() ? reservedEnd : slots;
if (stop > 0)
fprintf(stderr, obj->isNative() ? "reserved slots:\n" : "slots:\n");
for (uint32_t i = 0; i < stop; i++) {
fprintf(stderr, " %3d ", i);
if (i < reservedEnd)
fprintf(stderr, "(reserved) ");
fprintf(stderr, "= ");
dumpValue(obj->getSlot(i));
fputc('\n', stderr);
}
if (obj->isNative()) {
fprintf(stderr, "properties:\n");
Vector<Shape *, 8, SystemAllocPolicy> props;
for (Shape::Range<NoGC> r(obj->lastProperty()); !r.empty(); r.popFront())
props.append(&r.front());
for (size_t i = props.length(); i-- != 0;)
DumpProperty(obj, *props[i]);
}
fputc('\n', stderr);
}
static void
MaybeDumpObject(const char *name, JSObject *obj)
{
if (obj) {
fprintf(stderr, " %s: ", name);
dumpValue(ObjectValue(*obj));
fputc('\n', stderr);
}
}
static void
MaybeDumpValue(const char *name, const Value &v)
{
if (!v.isNull()) {
fprintf(stderr, " %s: ", name);
dumpValue(v);
fputc('\n', stderr);
}
}
JS_FRIEND_API(void)
js_DumpStackFrame(JSContext *cx, StackFrame *start)
{
/* This should only called during live debugging. */
ScriptFrameIter i(cx, ScriptFrameIter::GO_THROUGH_SAVED);
if (!start) {
if (i.done()) {
fprintf(stderr, "no stack for cx = %p\n", (void*) cx);
return;
}
} else {
while (!i.done() && !i.isJit() && i.interpFrame() != start)
++i;
if (i.done()) {
fprintf(stderr, "fp = %p not found in cx = %p\n",
(void *)start, (void *)cx);
return;
}
}
for (; !i.done(); ++i) {
if (i.isJit())
fprintf(stderr, "JIT frame\n");
else
fprintf(stderr, "StackFrame at %p\n", (void *) i.interpFrame());
if (i.isFunctionFrame()) {
fprintf(stderr, "callee fun: ");
dumpValue(i.calleev());
} else {
fprintf(stderr, "global frame, no callee");
}
fputc('\n', stderr);
fprintf(stderr, "file %s line %u\n",
i.script()->filename(), (unsigned) i.script()->lineno());
if (jsbytecode *pc = i.pc()) {
fprintf(stderr, " pc = %p\n", pc);
fprintf(stderr, " current op: %s\n", js_CodeName[*pc]);
MaybeDumpObject("blockChain", i.script()->getBlockScope(pc));
}
MaybeDumpValue("this", i.thisv());
if (!i.isJit()) {
fprintf(stderr, " rval: ");
dumpValue(i.interpFrame()->returnValue());
fputc('\n', stderr);
}
fprintf(stderr, " flags:");
if (i.isConstructing())
fprintf(stderr, " constructing");
if (!i.isJit() && i.interpFrame()->isDebuggerFrame())
fprintf(stderr, " debugger");
if (i.isEvalFrame())
fprintf(stderr, " eval");
if (!i.isJit() && i.interpFrame()->isYielding())
fprintf(stderr, " yielding");
if (!i.isJit() && i.interpFrame()->isGeneratorFrame())
fprintf(stderr, " generator");
fputc('\n', stderr);
fprintf(stderr, " scopeChain: (JSObject *) %p\n", (void *) i.scopeChain());
fputc('\n', stderr);
}
}
#endif /* DEBUG */
JS_FRIEND_API(void)
js_DumpBacktrace(JSContext *cx)
{
Sprinter sprinter(cx);
sprinter.init();
size_t depth = 0;
for (ScriptFrameIter i(cx); !i.done(); ++i, ++depth) {
const char *filename = JS_GetScriptFilename(cx, i.script());
unsigned line = JS_PCToLineNumber(cx, i.script(), i.pc());
JSScript *script = i.script();
sprinter.printf("#%d %14p %s:%d (%p @ %d)\n",
depth, (i.isJit() ? 0 : i.interpFrame()), filename, line,
script, script->pcToOffset(i.pc()));
}
fprintf(stdout, "%s", sprinter.string());
}
void
JSObject::addSizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf, JS::ObjectsExtraSizes *sizes)
{
if (hasDynamicSlots())
sizes->mallocHeapSlots += mallocSizeOf(slots);
if (hasDynamicElements()) {
js::ObjectElements *elements = getElementsHeader();
if (JS_UNLIKELY(elements->isAsmJSArrayBuffer())) {
#if defined (JS_CPU_X64)
// On x64, ArrayBufferObject::prepareForAsmJS switches the
// ArrayBufferObject to use mmap'd storage.
sizes->nonHeapElementsAsmJS += as<ArrayBufferObject>().byteLength();
#else
sizes->mallocHeapElementsAsmJS += mallocSizeOf(elements);
#endif
} else {
sizes->mallocHeapElementsNonAsmJS += mallocSizeOf(elements);
}
}
// Other things may be measured in the future if DMD indicates it is worthwhile.
if (is<JSFunction>() ||
is<JSObject>() ||
is<ArrayObject>() ||
is<CallObject>() ||
is<RegExpObject>() ||
is<ProxyObject>())
{
// Do nothing. But this function is hot, and we win by getting the
// common cases out of the way early. Some stats on the most common
// classes, as measured during a vanilla browser session:
// - (53.7%, 53.7%): Function
// - (18.0%, 71.7%): Object
// - (16.9%, 88.6%): Array
// - ( 3.9%, 92.5%): Call
// - ( 2.8%, 95.3%): RegExp
// - ( 1.0%, 96.4%): Proxy
} else if (is<ArgumentsObject>()) {
sizes->mallocHeapArgumentsData += as<ArgumentsObject>().sizeOfMisc(mallocSizeOf);
} else if (is<RegExpStaticsObject>()) {
sizes->mallocHeapRegExpStatics += as<RegExpStaticsObject>().sizeOfData(mallocSizeOf);
} else if (is<PropertyIteratorObject>()) {
sizes->mallocHeapPropertyIteratorData += as<PropertyIteratorObject>().sizeOfMisc(mallocSizeOf);
#ifdef JS_ION
} else if (is<AsmJSModuleObject>()) {
as<AsmJSModuleObject>().addSizeOfMisc(mallocSizeOf, &sizes->nonHeapCodeAsmJS,
&sizes->mallocHeapAsmJSModuleData);
#endif
#ifdef JS_HAS_CTYPES
} else {
// This must be the last case.
sizes->mallocHeapCtypesData +=
js::SizeOfDataIfCDataObject(mallocSizeOf, const_cast<JSObject *>(this));
#endif
}
}
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