https://github.com/mozilla/gecko-dev
Tip revision: f8c9d69b7f4d153bebd63ec52cb5399a404f82b7 authored by ffxbld on 26 June 2015, 18:24:57 UTC
Added FIREFOX_39_0_RELEASE FIREFOX_39_0_BUILD5 tag(s) for changeset 78c25ce5f523. DONTBUILD CLOSED TREE a=release
Added FIREFOX_39_0_RELEASE FIREFOX_39_0_BUILD5 tag(s) for changeset 78c25ce5f523. DONTBUILD CLOSED TREE a=release
Tip revision: f8c9d69
jsobj.cpp
/* -*- 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/SizePrintfMacros.h"
#include "mozilla/TemplateLib.h"
#include "mozilla/UniquePtr.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 "jsscript.h"
#include "jsstr.h"
#include "jstypes.h"
#include "jsutil.h"
#include "jswatchpoint.h"
#include "jswrapper.h"
#include "asmjs/AsmJSModule.h"
#include "builtin/Eval.h"
#include "builtin/Object.h"
#include "builtin/SymbolObject.h"
#include "frontend/BytecodeCompiler.h"
#include "gc/Marking.h"
#include "jit/BaselineJIT.h"
#include "js/MemoryMetrics.h"
#include "js/Proxy.h"
#include "vm/ArgumentsObject.h"
#include "vm/Interpreter.h"
#include "vm/ProxyObject.h"
#include "vm/RegExpStaticsObject.h"
#include "vm/Shape.h"
#include "vm/TypedArrayCommon.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/Interpreter-inl.h"
#include "vm/NativeObject-inl.h"
#include "vm/NumberObject-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 mozilla::DebugOnly;
using mozilla::Maybe;
using mozilla::UniquePtr;
JS_FRIEND_API(JSObject*)
JS_ObjectToInnerObject(JSContext* cx, HandleObject obj)
{
if (!obj) {
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_INACTIVE);
return nullptr;
}
return GetInnerObject(obj);
}
JS_FRIEND_API(JSObject*)
JS_ObjectToOuterObject(JSContext* cx, HandleObject obj)
{
assertSameCompartment(cx, obj);
return GetOuterObject(cx, obj);
}
JSObject*
js::NonNullObject(JSContext* cx, const Value& v)
{
if (v.isPrimitive()) {
RootedValue value(cx, v);
UniquePtr<char[], JS::FreePolicy> bytes =
DecompileValueGenerator(cx, JSDVG_SEARCH_STACK, value, NullPtr());
if (!bytes)
return nullptr;
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_NOT_NONNULL_OBJECT, bytes.get());
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.isSymbol())
return "symbol";
if (v.isNumber())
return "number";
if (v.isBoolean())
return "boolean";
if (v.isNull())
return "null";
if (v.isUndefined())
return "undefined";
return "value";
}
bool
js::FromPropertyDescriptor(JSContext* cx, Handle<PropertyDescriptor> desc,
MutableHandleValue vp)
{
if (!desc.object()) {
vp.setUndefined();
return true;
}
RootedObject obj(cx, NewBuiltinClassInstance<PlainObject>(cx));
if (!obj)
return false;
const JSAtomState& names = cx->names();
RootedValue v(cx);
if (desc.hasConfigurable()) {
v.setBoolean(desc.configurable());
if (!DefineProperty(cx, obj, names.configurable, v))
return false;
}
if (desc.hasEnumerable()) {
v.setBoolean(desc.enumerable());
if (!DefineProperty(cx, obj, names.enumerable, v))
return false;
}
if (desc.hasValue()) {
if (!DefineProperty(cx, obj, names.value, desc.value()))
return false;
}
if (desc.hasWritable()) {
v.setBoolean(desc.writable());
if (!DefineProperty(cx, obj, names.writable, v))
return false;
}
if (desc.hasGetterObject()) {
if (JSObject* get = desc.getterObject())
v.setObject(*get);
else
v.setUndefined();
if (!DefineProperty(cx, obj, names.get, v))
return false;
}
if (desc.hasSetterObject()) {
if (JSObject* set = desc.setterObject())
v.setObject(*set);
else
v.setUndefined();
if (!DefineProperty(cx, obj, names.set, v))
return false;
}
vp.setObject(*obj);
return true;
}
bool
js::GetFirstArgumentAsObject(JSContext* cx, const CallArgs& args, const char* method,
MutableHandleObject objp)
{
if (args.length() == 0) {
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_MORE_ARGS_NEEDED,
method, "0", "s");
return false;
}
HandleValue v = args[0];
if (!v.isObject()) {
UniquePtr<char[], JS::FreePolicy> bytes =
DecompileValueGenerator(cx, JSDVG_SEARCH_STACK, v, NullPtr());
if (!bytes)
return false;
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_UNEXPECTED_TYPE,
bytes.get(), "not an object");
return false;
}
objp.set(&v.toObject());
return true;
}
static bool
GetPropertyIfPresent(JSContext* cx, HandleObject obj, HandleId id, MutableHandleValue vp,
bool* foundp)
{
if (!HasProperty(cx, obj, id, foundp))
return false;
if (!*foundp) {
vp.setUndefined();
return true;
}
return GetProperty(cx, obj, obj, id, vp);
}
bool
js::Throw(JSContext* cx, jsid id, unsigned errorNumber)
{
MOZ_ASSERT(js_ErrorFormatString[errorNumber].argCount == 1);
RootedValue idVal(cx, IdToValue(id));
JSString* idstr = ValueToSource(cx, idVal);
if (!idstr)
return false;
JSAutoByteString bytes(cx, idstr);
if (!bytes)
return false;
JS_ReportErrorNumber(cx, 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));
ReportValueErrorFlags(cx, JSREPORT_ERROR, errorNumber,
JSDVG_IGNORE_STACK, val, NullPtr(),
nullptr, nullptr);
} else {
MOZ_ASSERT(js_ErrorFormatString[errorNumber].argCount == 0);
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, errorNumber);
}
return false;
}
/*** Standard-compliant property definition (used by Object.defineProperty) **********************/
static bool
DefinePropertyOnObject(JSContext* cx, HandleNativeObject obj, HandleId id,
Handle<PropertyDescriptor> desc, ObjectOpResult& result)
{
/* 8.12.9 step 1. */
RootedShape shape(cx);
MOZ_ASSERT(!obj->getOps()->lookupProperty);
if (!NativeLookupOwnProperty<CanGC>(cx, obj, id, &shape))
return false;
MOZ_ASSERT(!obj->getOps()->defineProperty);
/* 8.12.9 steps 2-4. */
if (!shape) {
bool extensible;
if (!IsExtensible(cx, obj, &extensible))
return false;
if (!extensible)
return result.fail(JSMSG_OBJECT_NOT_EXTENSIBLE);
if (desc.isGenericDescriptor() || desc.isDataDescriptor()) {
MOZ_ASSERT(!obj->getOps()->defineProperty);
RootedValue v(cx, desc.hasValue() ? desc.value() : UndefinedValue());
unsigned attrs = desc.attributes() & (JSPROP_PERMANENT | JSPROP_ENUMERATE | JSPROP_READONLY);
if (!desc.hasConfigurable())
attrs |= JSPROP_PERMANENT;
if (!desc.hasWritable())
attrs |= JSPROP_READONLY;
return NativeDefineProperty(cx, obj, id, v, nullptr, nullptr, attrs, result);
}
MOZ_ASSERT(desc.isAccessorDescriptor());
unsigned attrs = desc.attributes() & (JSPROP_PERMANENT | JSPROP_ENUMERATE |
JSPROP_SHARED | JSPROP_GETTER | JSPROP_SETTER);
if (!desc.hasConfigurable())
attrs |= JSPROP_PERMANENT;
return NativeDefineProperty(cx, obj, id, UndefinedHandleValue,
desc.getter(), desc.setter(), attrs, result);
}
/* 8.12.9 steps 5-6 (note 5 is merely a special case of 6). */
RootedValue v(cx);
bool shapeDataDescriptor = true,
shapeAccessorDescriptor = false,
shapeWritable = true,
shapeConfigurable = true,
shapeEnumerable = true,
shapeHasDefaultGetter = true,
shapeHasDefaultSetter = true,
shapeHasGetterValue = false,
shapeHasSetterValue = false;
uint8_t shapeAttributes = GetShapeAttributes(obj, shape);
if (!IsImplicitDenseOrTypedArrayElement(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.hasGetterObject()) {
if (!shape->hasGetterValue() || desc.getterObject() != shape->getterObject())
break;
}
if (desc.hasSetterObject()) {
if (!shape->hasSetterValue() || desc.setterObject() != shape->setterObject())
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 (IsImplicitDenseOrTypedArrayElement(shape)) {
v = obj->getDenseOrTypedArrayElement(JSID_TO_INT(id));
} else if (shape->isDataDescriptor()) {
/*
* We must rule out a non-configurable js::SetterOp-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 result.fail(JSMSG_CANT_REDEFINE_PROP);
}
if (!NativeGetExistingProperty(cx, obj, obj, 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::GetterOp 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
* GetterOp-based data properties and test before the
* SameValue check later on in order to re-use that "if
* (!SameValue) return false" logic.
*
* This function is large and complex enough that it
* seems best to repeat a small bit of code and return
* result.fail() ASAP, instead of being clever.
*/
if (!shapeConfigurable &&
(!shape->hasDefaultGetter() || !shape->hasDefaultSetter()))
{
return result.fail(JSMSG_CANT_REDEFINE_PROP);
}
break;
}
}
if (desc.hasWritable() && desc.writable() != shapeWritable)
break;
} else {
/* The only fields in desc will be handled below. */
MOZ_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. */
return result.succeed();
} while (0);
/* 8.12.9 step 7. */
if (!shapeConfigurable) {
if ((desc.hasConfigurable() && desc.configurable()) ||
(desc.hasEnumerable() && desc.enumerable() != shape->enumerable())) {
return result.fail(JSMSG_CANT_REDEFINE_PROP);
}
}
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 result.fail(JSMSG_CANT_REDEFINE_PROP);
} else if (desc.isDataDescriptor()) {
/* 8.12.9 step 10. */
MOZ_ASSERT(shapeDataDescriptor);
if (!shapeConfigurable && !shape->writable()) {
if (desc.hasWritable() && desc.writable())
return result.fail(JSMSG_CANT_REDEFINE_PROP);
if (desc.hasValue()) {
bool same;
if (!SameValue(cx, desc.value(), v, &same))
return false;
if (!same)
return result.fail(JSMSG_CANT_REDEFINE_PROP);
}
}
callDelProperty = !shapeHasDefaultGetter || !shapeHasDefaultSetter;
} else {
/* 8.12.9 step 11. */
MOZ_ASSERT(desc.isAccessorDescriptor() && shape->isAccessorDescriptor());
if (!shape->configurable()) {
// The hasSetterValue() and hasGetterValue() calls below ought to
// be redundant here, because accessor shapes should always have
// both JSPROP_GETTER and JSPROP_SETTER. But this is not the case
// currently; in particular Object.defineProperty(obj, key, {get: fn})
// creates a property without JSPROP_SETTER (bug 1133315).
if (desc.hasSetterObject() &&
desc.setterObject() != (shape->hasSetterValue() ? shape->setterObject() : nullptr))
{
return result.fail(JSMSG_CANT_REDEFINE_PROP);
}
if (desc.hasGetterObject() &&
desc.getterObject() != (shape->hasGetterValue() ? shape->getterObject() : nullptr))
{
return result.fail(JSMSG_CANT_REDEFINE_PROP);
}
}
}
/* 8.12.9 step 12. */
unsigned attrs;
GetterOp getter;
SetterOp 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 = IsImplicitDenseOrTypedArrayElement(shape) ? nullptr : shape->getter();
setter = IsImplicitDenseOrTypedArrayElement(shape) ? nullptr : shape->setter();
} else if (desc.isDataDescriptor()) {
/* Watch out for accessor -> data transformations here. */
unsigned changed = JSPROP_GETTER | JSPROP_SETTER | JSPROP_SHARED;
unsigned descAttrs = desc.attributes();
if (desc.hasConfigurable())
changed |= JSPROP_PERMANENT;
if (desc.hasEnumerable())
changed |= JSPROP_ENUMERATE;
if (desc.hasWritable()) {
changed |= JSPROP_READONLY;
} else if (!shapeDataDescriptor) {
changed |= JSPROP_READONLY;
descAttrs |= JSPROP_READONLY;
}
if (desc.hasValue())
v = desc.value();
attrs = (descAttrs & changed) | (shapeAttributes & ~changed);
getter = nullptr;
setter = nullptr;
} else {
MOZ_ASSERT(desc.isAccessorDescriptor());
/* 8.12.9 step 12. */
unsigned changed = 0;
if (desc.hasConfigurable())
changed |= JSPROP_PERMANENT;
if (desc.hasEnumerable())
changed |= JSPROP_ENUMERATE;
if (desc.hasGetterObject())
changed |= JSPROP_GETTER | JSPROP_SHARED | JSPROP_READONLY;
if (desc.hasSetterObject())
changed |= JSPROP_SETTER | JSPROP_SHARED | JSPROP_READONLY;
attrs = (desc.attributes() & changed) | (shapeAttributes & ~changed);
if (desc.hasGetterObject()) {
getter = desc.getter();
} else {
getter = (shapeHasDefaultGetter && !shapeHasGetterValue)
? nullptr
: shape->getter();
}
if (desc.hasSetterObject()) {
setter = desc.setter();
} else {
setter = (shapeHasDefaultSetter && !shapeHasSetterValue)
? nullptr
: shape->setter();
}
}
/*
* 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) {
ObjectOpResult ignored;
if (!CallJSDeletePropertyOp(cx, obj->getClass()->delProperty, obj, id, ignored))
return false;
}
return NativeDefineProperty(cx, obj, id, v, getter, setter, attrs, result);
}
/* ES6 20130308 draft 8.4.2.1 [[DefineOwnProperty]] */
static bool
DefinePropertyOnArray(JSContext* cx, Handle<ArrayObject*> arr, HandleId id,
Handle<PropertyDescriptor> desc, ObjectOpResult& result)
{
/* 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(cx, desc.value(), &newLen))
return false;
v.setNumber(newLen);
} else {
v.setNumber(arr->length());
}
if (desc.hasConfigurable() && desc.configurable())
return result.fail(JSMSG_CANT_REDEFINE_PROP);
if (desc.hasEnumerable() && desc.enumerable())
return result.fail(JSMSG_CANT_REDEFINE_PROP);
if (desc.isAccessorDescriptor())
return result.fail(JSMSG_CANT_REDEFINE_PROP);
unsigned attrs = arr->lookup(cx, id)->attributes();
if (!arr->lengthIsWritable()) {
if (desc.hasWritable() && desc.writable())
return result.fail(JSMSG_CANT_REDEFINE_PROP);
} else {
if (desc.hasWritable() && !desc.writable())
attrs = attrs | JSPROP_READONLY;
}
return ArraySetLength(cx, arr, id, attrs, v, result);
}
/* Step 3. */
uint32_t index;
if (IdIsIndex(id, &index)) {
/* Step 3b. */
uint32_t oldLen = arr->length();
/* Steps 3a, 3e. */
if (index >= oldLen && !arr->lengthIsWritable())
return result.fail(JSMSG_CANT_APPEND_TO_ARRAY);
/* Steps 3f-j. */
return DefinePropertyOnObject(cx, arr, id, desc, result);
}
/* Step 4. */
return DefinePropertyOnObject(cx, arr, id, desc, result);
}
// ES6 draft rev31 9.4.5.3 [[DefineOwnProperty]]
static bool
DefinePropertyOnTypedArray(JSContext* cx, HandleObject obj, HandleId id,
Handle<PropertyDescriptor> desc, ObjectOpResult& result)
{
MOZ_ASSERT(IsAnyTypedArray(obj));
// Steps 3.a-c.
uint64_t index;
if (IsTypedArrayIndex(id, &index)) {
// These are all substeps of 3.c.
// Steps i-vi.
// We (wrongly) ignore out of range defines with a value.
if (index >= AnyTypedArrayLength(obj))
return result.succeed();
// Step vii.
if (desc.isAccessorDescriptor())
return result.fail(JSMSG_CANT_REDEFINE_PROP);
// Step viii.
if (desc.hasConfigurable() && desc.configurable())
return result.fail(JSMSG_CANT_REDEFINE_PROP);
// Step ix.
if (desc.hasEnumerable() && !desc.enumerable())
return result.fail(JSMSG_CANT_REDEFINE_PROP);
// Step x.
if (desc.hasWritable() && !desc.writable())
return result.fail(JSMSG_CANT_REDEFINE_PROP);
// Step xi.
if (desc.hasValue()) {
double d;
if (!ToNumber(cx, desc.value(), &d))
return false;
if (obj->is<TypedArrayObject>())
TypedArrayObject::setElement(obj->as<TypedArrayObject>(), index, d);
else
SharedTypedArrayObject::setElement(obj->as<SharedTypedArrayObject>(), index, d);
}
// Step xii.
return result.succeed();
}
// Step 4.
return DefinePropertyOnObject(cx, obj.as<NativeObject>(), id, desc, result);
}
bool
js::StandardDefineProperty(JSContext* cx, HandleObject obj, HandleId id,
Handle<PropertyDescriptor> desc, ObjectOpResult& result)
{
if (obj->is<ArrayObject>()) {
Rooted<ArrayObject*> arr(cx, &obj->as<ArrayObject>());
return DefinePropertyOnArray(cx, arr, id, desc, result);
}
if (IsAnyTypedArray(obj))
return DefinePropertyOnTypedArray(cx, obj, id, desc, result);
if (obj->is<UnboxedPlainObject>() && !UnboxedPlainObject::convertToNative(cx, obj))
return false;
if (obj->getOps()->lookupProperty) {
if (obj->is<ProxyObject>()) {
Rooted<PropertyDescriptor> pd(cx, desc);
pd.object().set(obj);
return Proxy::defineProperty(cx, obj, id, pd, result);
}
return result.fail(JSMSG_OBJECT_NOT_EXTENSIBLE);
}
return DefinePropertyOnObject(cx, obj.as<NativeObject>(), id, desc, result);
}
bool
js::StandardDefineProperty(JSContext* cx, HandleObject obj, HandleId id,
Handle<PropertyDescriptor> desc)
{
ObjectOpResult success;
return StandardDefineProperty(cx, obj, id, desc, success) &&
success.checkStrict(cx, obj, id);
}
bool
CheckCallable(JSContext* cx, JSObject* obj, const char* fieldName)
{
if (obj && !obj->isCallable()) {
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_BAD_GET_SET_FIELD,
fieldName);
return false;
}
return true;
}
bool
js::ToPropertyDescriptor(JSContext* cx, HandleValue descval, bool checkAccessors,
MutableHandle<PropertyDescriptor> desc)
{
// step 2
if (!descval.isObject()) {
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_NOT_NONNULL_OBJECT,
InformalValueTypeName(descval));
return false;
}
RootedObject obj(cx, &descval.toObject());
// step 3
desc.clear();
bool found = false;
RootedId id(cx);
RootedValue v(cx);
unsigned attrs = 0;
// step 4
id = NameToId(cx->names().enumerable);
if (!GetPropertyIfPresent(cx, obj, id, &v, &found))
return false;
if (found) {
if (ToBoolean(v))
attrs |= JSPROP_ENUMERATE;
} else {
attrs |= JSPROP_IGNORE_ENUMERATE;
}
// step 5
id = NameToId(cx->names().configurable);
if (!GetPropertyIfPresent(cx, obj, id, &v, &found))
return false;
if (found) {
if (!ToBoolean(v))
attrs |= JSPROP_PERMANENT;
} else {
attrs |= JSPROP_IGNORE_PERMANENT;
}
// step 6
id = NameToId(cx->names().value);
if (!GetPropertyIfPresent(cx, obj, id, &v, &found))
return false;
if (found)
desc.value().set(v);
else
attrs |= JSPROP_IGNORE_VALUE;
// step 7
id = NameToId(cx->names().writable);
if (!GetPropertyIfPresent(cx, obj, id, &v, &found))
return false;
if (found) {
if (!ToBoolean(v))
attrs |= JSPROP_READONLY;
} else {
attrs |= JSPROP_IGNORE_READONLY;
}
// step 8
bool hasGetOrSet;
id = NameToId(cx->names().get);
if (!GetPropertyIfPresent(cx, obj, id, &v, &found))
return false;
hasGetOrSet = found;
if (found) {
if (v.isObject()) {
if (checkAccessors && !CheckCallable(cx, &v.toObject(), js_getter_str))
return false;
desc.setGetterObject(&v.toObject());
desc.attributesRef() |= JSPROP_GETTER;
} else if (!v.isUndefined()) {
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_BAD_GET_SET_FIELD,
js_getter_str);
return false;
}
attrs |= JSPROP_GETTER | JSPROP_SHARED;
}
// step 9
id = NameToId(cx->names().set);
if (!GetPropertyIfPresent(cx, obj, id, &v, &found))
return false;
hasGetOrSet |= found;
if (found) {
if (v.isObject()) {
if (checkAccessors && !CheckCallable(cx, &v.toObject(), js_setter_str))
return false;
desc.setSetterObject(&v.toObject());
desc.attributesRef() |= JSPROP_SETTER;
} else if (!v.isUndefined()) {
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_BAD_GET_SET_FIELD,
js_setter_str);
return false;
}
attrs |= JSPROP_SETTER | JSPROP_SHARED;
}
// step 10
if (hasGetOrSet) {
if (!(attrs & JSPROP_IGNORE_READONLY) || !(attrs & JSPROP_IGNORE_VALUE)) {
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_INVALID_DESCRIPTOR);
return false;
}
// By convention, these bits are not used on accessor descriptors.
attrs &= ~(JSPROP_IGNORE_READONLY | JSPROP_IGNORE_VALUE);
}
desc.setAttributes(attrs);
MOZ_ASSERT_IF(attrs & JSPROP_READONLY, !(attrs & (JSPROP_GETTER | JSPROP_SETTER)));
MOZ_ASSERT_IF(attrs & (JSPROP_GETTER | JSPROP_SETTER), attrs & JSPROP_SHARED);
return true;
}
bool
js::CheckPropertyDescriptorAccessors(JSContext* cx, Handle<PropertyDescriptor> desc)
{
if (desc.hasGetterObject()) {
if (!CheckCallable(cx, desc.getterObject(), js_getter_str))
return false;
}
if (desc.hasSetterObject()) {
if (!CheckCallable(cx, desc.setterObject(), js_setter_str))
return false;
}
return true;
}
void
js::CompletePropertyDescriptor(MutableHandle<PropertyDescriptor> desc)
{
if (desc.isGenericDescriptor() || desc.isDataDescriptor()) {
if (!desc.hasValue())
desc.value().setUndefined();
if (!desc.hasWritable())
desc.attributesRef() |= JSPROP_READONLY;
desc.attributesRef() &= ~(JSPROP_IGNORE_READONLY | JSPROP_IGNORE_VALUE);
} else {
if (!desc.hasGetterObject())
desc.setGetterObject(nullptr);
if (!desc.hasSetterObject())
desc.setSetterObject(nullptr);
desc.attributesRef() |= JSPROP_GETTER | JSPROP_SETTER | JSPROP_SHARED;
}
if (!desc.hasEnumerable())
desc.attributesRef() &= ~JSPROP_ENUMERATE;
if (!desc.hasConfigurable())
desc.attributesRef() |= JSPROP_PERMANENT;
desc.attributesRef() &= ~(JSPROP_IGNORE_PERMANENT | JSPROP_IGNORE_ENUMERATE);
}
bool
js::ReadPropertyDescriptors(JSContext* cx, HandleObject props, bool checkAccessors,
AutoIdVector* ids, AutoPropertyDescriptorVector* descs)
{
if (!GetPropertyKeys(cx, props, JSITER_OWNONLY | JSITER_SYMBOLS, ids))
return false;
RootedId id(cx);
for (size_t i = 0, len = ids->length(); i < len; i++) {
id = (*ids)[i];
Rooted<PropertyDescriptor> desc(cx);
RootedValue v(cx);
if (!GetProperty(cx, props, props, id, &v) ||
!ToPropertyDescriptor(cx, v, checkAccessors, &desc) ||
!descs->append(desc))
{
return false;
}
}
return true;
}
bool
js::DefineProperties(JSContext* cx, HandleObject obj, HandleObject props)
{
AutoIdVector ids(cx);
AutoPropertyDescriptorVector descs(cx);
if (!ReadPropertyDescriptors(cx, props, true, &ids, &descs))
return false;
for (size_t i = 0, len = ids.length(); i < len; i++) {
if (!StandardDefineProperty(cx, obj, ids[i], descs[i]))
return false;
}
return true;
}
/*** Seal and freeze *****************************************************************************/
static unsigned
GetSealedOrFrozenAttributes(unsigned attrs, IntegrityLevel level)
{
/* Make all attributes permanent; if freezing, make data attributes read-only. */
if (level == IntegrityLevel::Frozen && !(attrs & (JSPROP_GETTER | JSPROP_SETTER)))
return JSPROP_PERMANENT | JSPROP_READONLY;
return JSPROP_PERMANENT;
}
/* ES6 draft rev 29 (6 Dec 2014) 7.3.13. */
bool
js::SetIntegrityLevel(JSContext* cx, HandleObject obj, IntegrityLevel level)
{
assertSameCompartment(cx, obj);
// Steps 3-5. (Steps 1-2 are redundant assertions.)
if (!PreventExtensions(cx, obj))
return false;
// Steps 6-7.
AutoIdVector keys(cx);
if (!GetPropertyKeys(cx, obj, JSITER_HIDDEN | JSITER_OWNONLY | JSITER_SYMBOLS, &keys))
return false;
// PreventExtensions must sparsify dense objects, so we can assign to holes
// without checks.
MOZ_ASSERT_IF(obj->isNative(), obj->as<NativeObject>().getDenseCapacity() == 0);
// Steps 8-9, loosely interpreted.
if (obj->isNative() && !obj->as<NativeObject>().inDictionaryMode() && !IsAnyTypedArray(obj)) {
HandleNativeObject nobj = obj.as<NativeObject>();
// 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, nobj->getClass(),
nobj->getTaggedProto(),
nobj->numFixedSlots(),
nobj->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(nobj->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 unrootedChild(shapes[i]);
RootedGeneric<StackShape*> child(cx, &unrootedChild);
child->attrs |= GetSealedOrFrozenAttributes(child->attrs, level);
if (!JSID_IS_EMPTY(child->propid) && level == IntegrityLevel::Frozen)
MarkTypePropertyNonWritable(cx, nobj, child->propid);
last = cx->compartment()->propertyTree.getChild(cx, last, *child);
if (!last)
return false;
}
MOZ_ASSERT(nobj->lastProperty()->slotSpan() == last->slotSpan());
JS_ALWAYS_TRUE(nobj->setLastProperty(cx, last));
} else {
RootedId id(cx);
Rooted<PropertyDescriptor> desc(cx);
const unsigned AllowConfigure = JSPROP_IGNORE_ENUMERATE | JSPROP_IGNORE_READONLY |
JSPROP_IGNORE_VALUE;
const unsigned AllowConfigureAndWritable = AllowConfigure & ~JSPROP_IGNORE_READONLY;
// 8.a/9.a. The two different loops are merged here.
for (size_t i = 0; i < keys.length(); i++) {
id = keys[i];
if (level == IntegrityLevel::Sealed) {
// 8.a.i.
desc.setAttributes(AllowConfigure | JSPROP_PERMANENT);
} else {
// 9.a.i-ii.
Rooted<PropertyDescriptor> currentDesc(cx);
if (!GetOwnPropertyDescriptor(cx, obj, id, ¤tDesc))
return false;
// 9.a.iii.
if (!currentDesc.object())
continue;
// 9.a.iii.1-2
if (currentDesc.isAccessorDescriptor())
desc.setAttributes(AllowConfigure | JSPROP_PERMANENT);
else
desc.setAttributes(AllowConfigureAndWritable | JSPROP_PERMANENT | JSPROP_READONLY);
}
desc.object().set(obj);
// 8.a.i-ii. / 9.a.iii.3-4
if (!StandardDefineProperty(cx, obj, id, desc))
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 StandardDefineProperty 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 (level == IntegrityLevel::Frozen && obj->is<ArrayObject>()) {
if (!obj->as<ArrayObject>().maybeCopyElementsForWrite(cx))
return false;
obj->as<ArrayObject>().getElementsHeader()->setNonwritableArrayLength();
}
return true;
}
// ES6 draft rev33 (12 Feb 2015) 7.3.15
bool
js::TestIntegrityLevel(JSContext* cx, HandleObject obj, IntegrityLevel level, bool* result)
{
// Steps 3-6. (Steps 1-2 are redundant assertions.)
bool status;
if (!IsExtensible(cx, obj, &status))
return false;
if (status) {
*result = false;
return true;
}
// Steps 7-8.
AutoIdVector props(cx);
if (!GetPropertyKeys(cx, obj, JSITER_HIDDEN | JSITER_OWNONLY | JSITER_SYMBOLS, &props))
return false;
// Step 9.
RootedId id(cx);
Rooted<PropertyDescriptor> desc(cx);
for (size_t i = 0, len = props.length(); i < len; i++) {
id = props[i];
// Steps 9.a-b.
if (!GetOwnPropertyDescriptor(cx, obj, id, &desc))
return false;
// Step 9.c.
if (!desc.object())
continue;
// Steps 9.c.i-ii.
if (desc.configurable() ||
(level == IntegrityLevel::Frozen && desc.isDataDescriptor() && desc.writable()))
{
*result = false;
return true;
}
}
// Step 10.
*result = true;
return true;
}
/* * */
/*
* 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::AllocKind::OBJECT8;
if (clasp == &JSFunction::class_)
return gc::AllocKind::OBJECT2;
return gc::AllocKind::OBJECT4;
}
static inline JSObject*
NewObject(ExclusiveContext* cx, HandleObjectGroup group, gc::AllocKind kind,
NewObjectKind newKind)
{
const Class* clasp = group->clasp();
MOZ_ASSERT(clasp != &ArrayObject::class_);
MOZ_ASSERT_IF(clasp == &JSFunction::class_,
kind == JSFunction::FinalizeKind || kind == JSFunction::ExtendedFinalizeKind);
// For objects which can have fixed data following the object, only use
// enough fixed slots to cover the number of reserved slots in the object,
// regardless of the allocation kind specified.
size_t nfixed = ClassCanHaveFixedData(clasp)
? GetGCKindSlots(gc::GetGCObjectKind(clasp), clasp)
: GetGCKindSlots(kind, clasp);
RootedShape shape(cx, EmptyShape::getInitialShape(cx, clasp, group->proto(), nfixed));
if (!shape)
return nullptr;
gc::InitialHeap heap = GetInitialHeap(newKind, clasp);
JSObject* obj = JSObject::create(cx, kind, heap, shape, group);
if (!obj)
return nullptr;
if (newKind == SingletonObject) {
RootedObject nobj(cx, obj);
if (!JSObject::setSingleton(cx, nobj))
return nullptr;
obj = nobj;
}
bool globalWithoutCustomTrace = clasp->trace == JS_GlobalObjectTraceHook &&
!cx->compartment()->options().getTrace();
if (clasp->trace && !globalWithoutCustomTrace)
MOZ_RELEASE_ASSERT(clasp->flags & JSCLASS_IMPLEMENTS_BARRIERS);
probes::CreateObject(cx, obj);
return obj;
}
void
NewObjectCache::fillProto(EntryIndex entry, const Class* clasp, js::TaggedProto proto,
gc::AllocKind kind, NativeObject* obj)
{
MOZ_ASSERT_IF(proto.isObject(), !proto.toObject()->is<GlobalObject>());
MOZ_ASSERT(obj->getTaggedProto() == proto);
return fill(entry, clasp, proto.raw(), kind, obj);
}
static bool
NewObjectWithTaggedProtoIsCachable(ExclusiveContext* cxArg, Handle<TaggedProto> proto,
NewObjectKind newKind, const Class* clasp)
{
return cxArg->isJSContext() &&
proto.isObject() &&
newKind == GenericObject &&
clasp->isNative() &&
!proto.toObject()->is<GlobalObject>();
}
JSObject*
js::NewObjectWithGivenTaggedProto(ExclusiveContext* cxArg, const Class* clasp,
Handle<TaggedProto> proto,
gc::AllocKind allocKind, NewObjectKind newKind)
{
if (CanBeFinalizedInBackground(allocKind, clasp))
allocKind = GetBackgroundAllocKind(allocKind);
bool isCachable = NewObjectWithTaggedProtoIsCachable(cxArg, proto, newKind, clasp);
if (isCachable) {
JSContext* cx = cxArg->asJSContext();
JSRuntime* rt = cx->runtime();
NewObjectCache& cache = rt->newObjectCache;
NewObjectCache::EntryIndex entry = -1;
if (cache.lookupProto(clasp, proto.toObject(), allocKind, &entry)) {
JSObject* obj = cache.newObjectFromHit(cx, entry, GetInitialHeap(newKind, clasp));
if (obj)
return obj;
}
}
RootedObjectGroup group(cxArg, ObjectGroup::defaultNewGroup(cxArg, clasp, proto, nullptr));
if (!group)
return nullptr;
RootedObject obj(cxArg, NewObject(cxArg, group, allocKind, newKind));
if (!obj)
return nullptr;
if (isCachable && !obj->as<NativeObject>().hasDynamicSlots()) {
NewObjectCache& cache = cxArg->asJSContext()->runtime()->newObjectCache;
NewObjectCache::EntryIndex entry = -1;
cache.lookupProto(clasp, proto.toObject(), allocKind, &entry);
cache.fillProto(entry, clasp, proto, allocKind, &obj->as<NativeObject>());
}
return obj;
}
static JSProtoKey
ClassProtoKeyOrAnonymousOrNull(const js::Class* clasp)
{
JSProtoKey key = JSCLASS_CACHED_PROTO_KEY(clasp);
if (key != JSProto_Null)
return key;
if (clasp->flags & JSCLASS_IS_ANONYMOUS)
return JSProto_Object;
return JSProto_Null;
}
static inline bool
NativeGetPureInline(NativeObject* pobj, Shape* shape, Value* vp)
{
if (shape->hasSlot()) {
*vp = pobj->getSlot(shape->slot());
MOZ_ASSERT(!vp->isMagic());
} else {
vp->setUndefined();
}
/* Fail if we have a custom getter. */
return shape->hasDefaultGetter();
}
static bool
FindClassPrototype(ExclusiveContext* cx, MutableHandleObject protop, const Class* clasp)
{
protop.set(nullptr);
JSAtom* atom = Atomize(cx, clasp->name, strlen(clasp->name));
if (!atom)
return false;
RootedId id(cx, AtomToId(atom));
RootedObject pobj(cx);
RootedShape shape(cx);
if (!NativeLookupProperty<CanGC>(cx, cx->global(), id, &pobj, &shape))
return false;
RootedObject ctor(cx);
if (shape && pobj->isNative()) {
if (shape->hasSlot()) {
RootedValue v(cx, pobj->as<NativeObject>().getSlot(shape->slot()));
if (v.isObject())
ctor = &v.toObject();
}
}
if (ctor && ctor->is<JSFunction>()) {
JSFunction* nctor = &ctor->as<JSFunction>();
RootedValue v(cx);
if (cx->isJSContext()) {
if (!GetProperty(cx->asJSContext(), ctor, ctor, cx->names().prototype, &v))
return false;
} else {
Shape* shape = nctor->lookup(cx, cx->names().prototype);
if (!shape || !NativeGetPureInline(nctor, shape, v.address()))
return false;
}
if (v.isObject())
protop.set(&v.toObject());
}
return true;
}
// Find the appropriate proto for a class. There are three different ways to achieve this:
// 1. Built-in classes have a cached proto and anonymous classes get Object.prototype.
// 2. Lookup global[clasp->name].prototype
// 3. Fallback to Object.prototype
//
// Step 2 is in some circumstances an observable operation, which is probably wrong
// as a matter of specifications. It's legacy garbage that we're working to remove eventually.
static bool
FindProto(ExclusiveContext* cx, const js::Class* clasp, MutableHandleObject proto)
{
JSProtoKey protoKey = ClassProtoKeyOrAnonymousOrNull(clasp);
if (protoKey != JSProto_Null)
return GetBuiltinPrototype(cx, protoKey, proto);
if (!FindClassPrototype(cx, proto, clasp))
return false;
if (!proto) {
// We're looking for the prototype of a class that is currently being
// resolved; the global object's resolve hook is on the
// stack. js::FindClassPrototype detects this goofy case and returns
// true with proto null. Fall back on Object.prototype.
MOZ_ASSERT(JSCLASS_CACHED_PROTO_KEY(clasp) == JSProto_Null);
return GetBuiltinPrototype(cx, JSProto_Object, proto);
}
return true;
}
static bool
NewObjectWithClassProtoIsCachable(ExclusiveContext* cxArg,
JSProtoKey protoKey, NewObjectKind newKind, const Class* clasp)
{
return cxArg->isJSContext() &&
protoKey != JSProto_Null &&
newKind == GenericObject &&
clasp->isNative();
}
JSObject*
js::NewObjectWithClassProtoCommon(ExclusiveContext* cxArg, const Class* clasp,
HandleObject protoArg,
gc::AllocKind allocKind, NewObjectKind newKind)
{
if (protoArg) {
return NewObjectWithGivenTaggedProto(cxArg, clasp, AsTaggedProto(protoArg),
allocKind, newKind);
}
if (CanBeFinalizedInBackground(allocKind, clasp))
allocKind = GetBackgroundAllocKind(allocKind);
Handle<GlobalObject*> global = 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 = ClassProtoKeyOrAnonymousOrNull(clasp);
bool isCachable = NewObjectWithClassProtoIsCachable(cxArg, protoKey, newKind, clasp);
if (isCachable) {
JSContext* cx = cxArg->asJSContext();
JSRuntime* rt = cx->runtime();
NewObjectCache& cache = rt->newObjectCache;
NewObjectCache::EntryIndex entry = -1;
if (cache.lookupGlobal(clasp, global, allocKind, &entry)) {
JSObject* obj = cache.newObjectFromHit(cx, entry, GetInitialHeap(newKind, clasp));
if (obj)
return obj;
}
}
RootedObject proto(cxArg, protoArg);
if (!FindProto(cxArg, clasp, &proto))
return nullptr;
Rooted<TaggedProto> taggedProto(cxArg, TaggedProto(proto));
RootedObjectGroup group(cxArg, ObjectGroup::defaultNewGroup(cxArg, clasp, taggedProto));
if (!group)
return nullptr;
JSObject* obj = NewObject(cxArg, group, allocKind, newKind);
if (!obj)
return nullptr;
if (isCachable && !obj->as<NativeObject>().hasDynamicSlots()) {
NewObjectCache& cache = cxArg->asJSContext()->runtime()->newObjectCache;
NewObjectCache::EntryIndex entry = -1;
cache.lookupGlobal(clasp, global, allocKind, &entry);
cache.fillGlobal(entry, clasp, global, allocKind,
&obj->as<NativeObject>());
}
return obj;
}
static bool
NewObjectWithGroupIsCachable(ExclusiveContext* cx, HandleObjectGroup group,
NewObjectKind newKind)
{
return group->proto().isObject() &&
newKind == GenericObject &&
group->clasp()->isNative() &&
(!group->newScript() || group->newScript()->analyzed()) &&
cx->isJSContext();
}
/*
* Create a plain object with the specified group. This bypasses getNewGroup to
* avoid losing creation site information for objects made by scripted 'new'.
*/
JSObject*
js::NewObjectWithGroupCommon(ExclusiveContext* cx, HandleObjectGroup group,
gc::AllocKind allocKind, NewObjectKind newKind)
{
MOZ_ASSERT(gc::IsObjectAllocKind(allocKind));
if (CanBeFinalizedInBackground(allocKind, group->clasp()))
allocKind = GetBackgroundAllocKind(allocKind);
bool isCachable = NewObjectWithGroupIsCachable(cx, group, newKind);
if (isCachable) {
NewObjectCache& cache = cx->asJSContext()->runtime()->newObjectCache;
NewObjectCache::EntryIndex entry = -1;
if (cache.lookupGroup(group, allocKind, &entry)) {
JSObject* obj = cache.newObjectFromHit(cx->asJSContext(), entry,
GetInitialHeap(newKind, group->clasp()));
if (obj)
return obj;
}
}
JSObject* obj = NewObject(cx, group, allocKind, newKind);
if (!obj)
return nullptr;
if (isCachable && !obj->as<NativeObject>().hasDynamicSlots()) {
NewObjectCache& cache = cx->asJSContext()->runtime()->newObjectCache;
NewObjectCache::EntryIndex entry = -1;
cache.lookupGroup(group, allocKind, &entry);
cache.fillGroup(entry, group, allocKind, &obj->as<NativeObject>());
}
return obj;
}
bool
js::NewObjectScriptedCall(JSContext* cx, MutableHandleObject pobj)
{
jsbytecode* pc;
RootedScript script(cx, cx->currentScript(&pc));
gc::AllocKind allocKind = NewObjectGCKind(&PlainObject::class_);
NewObjectKind newKind = GenericObject;
if (script && ObjectGroup::useSingletonForAllocationSite(script, pc, &PlainObject::class_))
newKind = SingletonObject;
RootedObject obj(cx, NewBuiltinClassInstance<PlainObject>(cx, allocKind, newKind));
if (!obj)
return false;
if (script) {
/* Try to specialize the group of the object to the scripted call site. */
if (!ObjectGroup::setAllocationSiteObjectGroup(cx, script, pc, obj, newKind == SingletonObject))
return false;
}
pobj.set(obj);
return true;
}
JSObject*
js::CreateThis(JSContext* cx, const Class* newclasp, HandleObject callee)
{
RootedValue protov(cx);
if (!GetProperty(cx, callee, callee, cx->names().prototype, &protov))
return nullptr;
RootedObject proto(cx, protov.isObjectOrNull() ? protov.toObjectOrNull() : nullptr);
gc::AllocKind kind = NewObjectGCKind(newclasp);
return NewObjectWithClassProto(cx, newclasp, proto, kind);
}
static inline JSObject*
CreateThisForFunctionWithGroup(JSContext* cx, HandleObjectGroup group,
NewObjectKind newKind)
{
if (group->maybeUnboxedLayout() && newKind != SingletonObject)
return UnboxedPlainObject::create(cx, group, newKind);
if (TypeNewScript* newScript = group->newScript()) {
if (newScript->analyzed()) {
// The definite properties analysis has been performed for this
// group, so get the shape and alloc kind to use from the
// TypeNewScript's template.
RootedPlainObject templateObject(cx, newScript->templateObject());
MOZ_ASSERT(templateObject->group() == group);
RootedPlainObject res(cx, CopyInitializerObject(cx, templateObject, newKind));
if (!res)
return nullptr;
if (newKind == SingletonObject) {
Rooted<TaggedProto> proto(cx, TaggedProto(templateObject->getProto()));
if (!res->splicePrototype(cx, &PlainObject::class_, proto))
return nullptr;
} else {
res->setGroup(group);
}
return res;
}
// The initial objects registered with a TypeNewScript can't be in the
// nursery.
if (newKind == GenericObject)
newKind = MaybeSingletonObject;
// Not enough objects with this group have been created yet, so make a
// plain object and register it with the group. Use the maximum number
// of fixed slots, as is also required by the TypeNewScript.
gc::AllocKind allocKind = GuessObjectGCKind(NativeObject::MAX_FIXED_SLOTS);
PlainObject* res = NewObjectWithGroup<PlainObject>(cx, group, allocKind, newKind);
if (!res)
return nullptr;
if (newKind != SingletonObject)
newScript->registerNewObject(res);
return res;
}
gc::AllocKind allocKind = NewObjectGCKind(&PlainObject::class_);
if (newKind == SingletonObject) {
Rooted<TaggedProto> protoRoot(cx, group->proto());
return NewObjectWithGivenTaggedProto(cx, &PlainObject::class_, protoRoot, allocKind, newKind);
}
return NewObjectWithGroup<PlainObject>(cx, group, allocKind, newKind);
}
JSObject*
js::CreateThisForFunctionWithProto(JSContext* cx, HandleObject callee, HandleObject proto,
NewObjectKind newKind /* = GenericObject */)
{
RootedObject res(cx);
if (proto) {
RootedObjectGroup group(cx, ObjectGroup::defaultNewGroup(cx, nullptr, TaggedProto(proto),
&callee->as<JSFunction>()));
if (!group)
return nullptr;
if (group->newScript() && !group->newScript()->analyzed()) {
bool regenerate;
if (!group->newScript()->maybeAnalyze(cx, group, ®enerate))
return nullptr;
if (regenerate) {
// The script was analyzed successfully and may have changed
// the new type table, so refetch the group.
group = ObjectGroup::defaultNewGroup(cx, nullptr, TaggedProto(proto),
&callee->as<JSFunction>());
MOZ_ASSERT(group && group->newScript());
}
}
res = CreateThisForFunctionWithGroup(cx, group, newKind);
} else {
gc::AllocKind allocKind = NewObjectGCKind(&PlainObject::class_);
res = NewObjectWithProto<PlainObject>(cx, proto, allocKind, newKind);
}
if (res) {
JSScript* script = callee->as<JSFunction>().getOrCreateScript(cx);
if (!script)
return nullptr;
TypeScript::SetThis(cx, script, TypeSet::ObjectType(res));
}
return res;
}
JSObject*
js::CreateThisForFunction(JSContext* cx, HandleObject callee, NewObjectKind newKind)
{
RootedValue protov(cx);
if (!GetProperty(cx, callee, callee, cx->names().prototype, &protov))
return nullptr;
RootedObject proto(cx);
if (protov.isObject())
proto = &protov.toObject();
JSObject* obj = CreateThisForFunctionWithProto(cx, callee, proto, newKind);
if (obj && newKind == SingletonObject) {
RootedPlainObject nobj(cx, &obj->as<PlainObject>());
/* Reshape the singleton before passing it as the 'this' value. */
NativeObject::clear(cx, nobj);
JSScript* calleeScript = callee->as<JSFunction>().nonLazyScript();
TypeScript::SetThis(cx, calleeScript, TypeSet::ObjectType(nobj));
return nobj;
}
return obj;
}
/* static */ bool
JSObject::nonNativeSetProperty(JSContext* cx, HandleObject obj, HandleId id, HandleValue v,
HandleValue receiver, ObjectOpResult& result)
{
RootedValue value(cx, v);
if (MOZ_UNLIKELY(obj->watched())) {
WatchpointMap* wpmap = cx->compartment()->watchpointMap;
if (wpmap && !wpmap->triggerWatchpoint(cx, obj, id, &value))
return false;
}
return obj->getOps()->setProperty(cx, obj, id, value, receiver, result);
}
/* static */ bool
JSObject::nonNativeSetElement(JSContext* cx, HandleObject obj, uint32_t index, HandleValue v,
HandleValue receiver, ObjectOpResult& result)
{
RootedId id(cx);
if (!IndexToId(cx, index, &id))
return false;
return nonNativeSetProperty(cx, obj, id, v, receiver, result);
}
JS_FRIEND_API(bool)
JS_CopyPropertyFrom(JSContext* cx, HandleId id, HandleObject target,
HandleObject obj, PropertyCopyBehavior copyBehavior)
{
// |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 JSGetterOp/JSSetterOp-implemented accessors.
if (desc.getter() && !desc.hasGetterObject())
return true;
if (desc.setter() && !desc.hasSetterObject())
return true;
if (copyBehavior == MakeNonConfigurableIntoConfigurable) {
// Mask off the JSPROP_PERMANENT bit.
desc.attributesRef() &= ~JSPROP_PERMANENT;
}
JSAutoCompartment ac(cx, target);
RootedId wrappedId(cx, id);
if (!cx->compartment()->wrap(cx, &desc))
return false;
return StandardDefineProperty(cx, target, wrappedId, desc);
}
JS_FRIEND_API(bool)
JS_CopyPropertiesFrom(JSContext* cx, HandleObject target, HandleObject obj)
{
JSAutoCompartment ac(cx, obj);
AutoIdVector props(cx);
if (!GetPropertyKeys(cx, obj, JSITER_OWNONLY | JSITER_HIDDEN | JSITER_SYMBOLS, &props))
return false;
for (size_t i = 0; i < props.length(); ++i) {
if (!JS_CopyPropertyFrom(cx, props[i], target, obj))
return false;
}
return true;
}
static bool
CopyProxyObject(JSContext* cx, Handle<ProxyObject*> from, Handle<ProxyObject*> to)
{
MOZ_ASSERT(from->getClass() == to->getClass());
if (from->is<WrapperObject>() &&
(Wrapper::wrapperHandler(from)->flags() &
Wrapper::CROSS_COMPARTMENT))
{
to->setCrossCompartmentPrivate(GetProxyPrivate(from));
} else {
RootedValue v(cx, GetProxyPrivate(from));
if (!cx->compartment()->wrap(cx, &v))
return false;
to->setSameCompartmentPrivate(v);
}
RootedValue v(cx);
for (size_t n = 0; n < PROXY_EXTRA_SLOTS; n++) {
v = GetProxyExtra(from, n);
if (!cx->compartment()->wrap(cx, &v))
return false;
SetProxyExtra(to, n, v);
}
return true;
}
JSObject*
js::CloneObject(JSContext* cx, HandleObject obj, Handle<js::TaggedProto> proto)
{
if (!obj->isNative() && !obj->is<ProxyObject>()) {
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr,
JSMSG_CANT_CLONE_OBJECT);
return nullptr;
}
RootedObject clone(cx);
if (obj->isNative()) {
clone = NewObjectWithGivenTaggedProto(cx, obj->getClass(), proto);
if (!clone)
return nullptr;
if (clone->is<JSFunction>() && (obj->compartment() != clone->compartment())) {
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr,
JSMSG_CANT_CLONE_OBJECT);
return nullptr;
}
if (obj->as<NativeObject>().hasPrivate())
clone->as<NativeObject>().setPrivate(obj->as<NativeObject>().getPrivate());
} else {
ProxyOptions options;
options.setClass(obj->getClass());
clone = ProxyObject::New(cx, GetProxyHandler(obj), JS::NullHandleValue, proto, options);
if (!clone)
return nullptr;
if (!CopyProxyObject(cx, obj.as<ProxyObject>(), clone.as<ProxyObject>()))
return nullptr;
}
return clone;
}
static bool
GetScriptArrayObjectElements(JSContext* cx, HandleArrayObject obj, AutoValueVector& values)
{
MOZ_ASSERT(!obj->isSingleton());
if (obj->nonProxyIsExtensible()) {
MOZ_ASSERT(obj->slotSpan() == 0);
if (!values.appendN(MagicValue(JS_ELEMENTS_HOLE), obj->getDenseInitializedLength()))
return false;
for (size_t i = 0; i < obj->getDenseInitializedLength(); i++)
values[i].set(obj->getDenseElement(i));
} else {
// Call site objects are frozen before they escape to script, which
// converts their dense elements into data properties.
for (Shape::Range<NoGC> r(obj->lastProperty()); !r.empty(); r.popFront()) {
Shape& shape = r.front();
if (shape.propid() == NameToId(cx->names().length))
continue;
MOZ_ASSERT(shape.isDataDescriptor());
// The 'raw' property is added before freezing call site objects.
// After an XDR or deep clone the script object will no longer be
// frozen, and the two objects will be connected again the first
// time the JSOP_CALLSITEOBJ executes.
if (shape.propid() == NameToId(cx->names().raw))
continue;
uint32_t index = JSID_TO_INT(shape.propid());
while (index >= values.length()) {
if (!values.append(MagicValue(JS_ELEMENTS_HOLE)))
return false;
}
values[index].set(obj->getSlot(shape.slot()));
}
}
return true;
}
static bool
GetScriptPlainObjectProperties(JSContext* cx, HandleObject obj, AutoIdValueVector& properties)
{
if (obj->is<PlainObject>()) {
PlainObject* nobj = &obj->as<PlainObject>();
if (!properties.appendN(IdValuePair(), nobj->slotSpan()))
return false;
for (Shape::Range<NoGC> r(nobj->lastProperty()); !r.empty(); r.popFront()) {
Shape& shape = r.front();
MOZ_ASSERT(shape.isDataDescriptor());
uint32_t slot = shape.slot();
properties[slot].get().id = shape.propid();
properties[slot].get().value = nobj->getSlot(slot);
}
for (size_t i = 0; i < nobj->getDenseInitializedLength(); i++) {
Value v = nobj->getDenseElement(i);
if (!v.isMagic(JS_ELEMENTS_HOLE) && !properties.append(IdValuePair(INT_TO_JSID(i), v)))
return false;
}
return true;
}
if (obj->is<UnboxedPlainObject>()) {
UnboxedPlainObject* nobj = &obj->as<UnboxedPlainObject>();
const UnboxedLayout& layout = nobj->layout();
if (!properties.appendN(IdValuePair(), layout.properties().length()))
return false;
for (size_t i = 0; i < layout.properties().length(); i++) {
const UnboxedLayout::Property& property = layout.properties()[i];
properties[i].get().id = NameToId(property.name);
properties[i].get().value = nobj->getValue(property);
}
return true;
}
MOZ_CRASH("Bad object kind");
}
static bool
DeepCloneValue(JSContext* cx, Value* vp, NewObjectKind newKind)
{
if (vp->isObject()) {
RootedObject obj(cx, &vp->toObject());
obj = DeepCloneObjectLiteral(cx, obj, newKind);
if (!obj)
return false;
vp->setObject(*obj);
}
return true;
}
JSObject*
js::DeepCloneObjectLiteral(JSContext* cx, HandleObject obj, NewObjectKind newKind)
{
/* NB: Keep this in sync with XDRObjectLiteral. */
MOZ_ASSERT_IF(obj->isSingleton(),
JS::CompartmentOptionsRef(cx).getSingletonsAsTemplates());
MOZ_ASSERT(obj->is<PlainObject>() || obj->is<UnboxedPlainObject>() || obj->is<ArrayObject>());
MOZ_ASSERT(cx->isInsideCurrentCompartment(obj));
MOZ_ASSERT(newKind != SingletonObject);
if (obj->is<ArrayObject>()) {
HandleArrayObject aobj = obj.as<ArrayObject>();
AutoValueVector values(cx);
if (!GetScriptArrayObjectElements(cx, aobj, values))
return nullptr;
// Deep clone any elements.
uint32_t initialized = aobj->getDenseInitializedLength();
for (uint32_t i = 0; i < initialized; ++i) {
if (!DeepCloneValue(cx, values[i].address(), newKind))
return nullptr;
}
RootedArrayObject clone(cx, NewDenseUnallocatedArray(cx, aobj->length(),
NullPtr(), newKind));
if (!clone || !clone->ensureElements(cx, values.length()))
return nullptr;
clone->setDenseInitializedLength(values.length());
clone->initDenseElements(0, values.begin(), values.length());
if (aobj->denseElementsAreCopyOnWrite()) {
if (!ObjectElements::MakeElementsCopyOnWrite(cx, clone))
return nullptr;
} else {
ObjectGroup::fixArrayGroup(cx, &clone->as<ArrayObject>());
}
return clone;
}
AutoIdValueVector properties(cx);
if (!GetScriptPlainObjectProperties(cx, obj, properties))
return nullptr;
for (size_t i = 0; i < properties.length(); i++) {
if (!DeepCloneValue(cx, &properties[i].get().value, newKind))
return nullptr;
}
if (obj->isSingleton())
newKind = SingletonObject;
return ObjectGroup::newPlainObject(cx, properties.begin(), properties.length(), newKind);
}
static bool
InitializePropertiesFromCompatibleNativeObject(JSContext* cx,
HandleNativeObject dst,
HandleNativeObject src)
{
assertSameCompartment(cx, src, dst);
MOZ_ASSERT(src->getClass() == dst->getClass());
MOZ_ASSERT(dst->lastProperty()->getObjectFlags() == 0);
MOZ_ASSERT(!src->isSingleton());
MOZ_ASSERT(src->numFixedSlots() == dst->numFixedSlots());
if (!dst->ensureElements(cx, src->getDenseInitializedLength()))
return false;
uint32_t initialized = src->getDenseInitializedLength();
for (uint32_t i = 0; i < initialized; ++i) {
dst->setDenseInitializedLength(i + 1);
dst->initDenseElement(i, src->getDenseElement(i));
}
MOZ_ASSERT(!src->hasPrivate());
RootedShape shape(cx);
if (src->getProto() == dst->getProto()) {
shape = src->lastProperty();
} else {
// We need to generate a new shape for dst that has dst's proto but all
// the property information from src. Note that we asserted above that
// dst's object flags are 0.
shape = EmptyShape::getInitialShape(cx, dst->getClass(), dst->getTaggedProto(),
dst->numFixedSlots(), 0);
if (!shape)
return false;
// Get an in-order list of the shapes in the src object.
AutoShapeVector shapes(cx);
for (Shape::Range<NoGC> r(src->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 unrootedChild(shapes[i]);
RootedGeneric<StackShape*> child(cx, &unrootedChild);
shape = cx->compartment()->propertyTree.getChild(cx, shape, *child);
if (!shape)
return false;
}
}
size_t span = shape->slotSpan();
if (!dst->setLastProperty(cx, shape))
return false;
for (size_t i = JSCLASS_RESERVED_SLOTS(src->getClass()); i < span; i++)
dst->setSlot(i, src->getSlot(i));
return true;
}
JS_FRIEND_API(bool)
JS_InitializePropertiesFromCompatibleNativeObject(JSContext* cx,
HandleObject dst,
HandleObject src)
{
return InitializePropertiesFromCompatibleNativeObject(cx,
dst.as<NativeObject>(),
src.as<NativeObject>());
}
template<XDRMode mode>
bool
js::XDRObjectLiteral(XDRState<mode>* xdr, MutableHandleObject obj)
{
/* NB: Keep this in sync with DeepCloneObjectLiteral. */
JSContext* cx = xdr->cx();
MOZ_ASSERT_IF(mode == XDR_ENCODE && obj->isSingleton(),
JS::CompartmentOptionsRef(cx).getSingletonsAsTemplates());
// Distinguish between objects and array classes.
uint32_t isArray = 0;
{
if (mode == XDR_ENCODE) {
MOZ_ASSERT(obj->is<PlainObject>() ||
obj->is<UnboxedPlainObject>() ||
obj->is<ArrayObject>());
isArray = obj->is<ArrayObject>() ? 1 : 0;
}
if (!xdr->codeUint32(&isArray))
return false;
}
RootedValue tmpValue(cx), tmpIdValue(cx);
RootedId tmpId(cx);
if (isArray) {
uint32_t length;
RootedArrayObject aobj(cx);
if (mode == XDR_ENCODE) {
aobj = &obj->as<ArrayObject>();
length = aobj->length();
}
if (!xdr->codeUint32(&length))
return false;
if (mode == XDR_DECODE) {
obj.set(NewDenseUnallocatedArray(cx, length, NullPtr(), TenuredObject));
if (!obj)
return false;
aobj = &obj->as<ArrayObject>();
}
AutoValueVector values(cx);
if (mode == XDR_ENCODE && !GetScriptArrayObjectElements(cx, aobj, values))
return false;
uint32_t initialized;
{
if (mode == XDR_ENCODE)
initialized = values.length();
if (!xdr->codeUint32(&initialized))
return false;
if (mode == XDR_DECODE) {
if (initialized) {
if (!aobj->ensureElements(cx, initialized))
return false;
}
}
}
// Recursively copy dense elements.
for (unsigned i = 0; i < initialized; i++) {
if (mode == XDR_ENCODE)
tmpValue = values[i];
if (!xdr->codeConstValue(&tmpValue))
return false;
if (mode == XDR_DECODE) {
aobj->setDenseInitializedLength(i + 1);
aobj->initDenseElement(i, tmpValue);
}
}
uint32_t copyOnWrite;
if (mode == XDR_ENCODE)
copyOnWrite = aobj->denseElementsAreCopyOnWrite();
if (!xdr->codeUint32(©OnWrite))
return false;
if (mode == XDR_DECODE) {
if (copyOnWrite) {
if (!ObjectElements::MakeElementsCopyOnWrite(cx, aobj))
return false;
} else {
ObjectGroup::fixArrayGroup(cx, aobj);
}
}
return true;
}
// Code the properties in the object.
AutoIdValueVector properties(cx);
if (mode == XDR_ENCODE && !GetScriptPlainObjectProperties(cx, obj, properties))
return false;
uint32_t nproperties = properties.length();
if (!xdr->codeUint32(&nproperties))
return false;
if (mode == XDR_DECODE && !properties.appendN(IdValuePair(), nproperties))
return false;
for (size_t i = 0; i < nproperties; i++) {
if (mode == XDR_ENCODE) {
tmpIdValue = IdToValue(properties[i].get().id);
tmpValue = properties[i].get().value;
}
if (!xdr->codeConstValue(&tmpIdValue) || !xdr->codeConstValue(&tmpValue))
return false;
if (mode == XDR_DECODE) {
if (!ValueToId<CanGC>(cx, tmpIdValue, &tmpId))
return false;
properties[i].get().id = tmpId;
properties[i].get().value = tmpValue;
}
}
// Code whether the object is a singleton.
uint32_t isSingleton;
if (mode == XDR_ENCODE)
isSingleton = obj->isSingleton() ? 1 : 0;
if (!xdr->codeUint32(&isSingleton))
return false;
if (mode == XDR_DECODE) {
NewObjectKind newKind = isSingleton ? SingletonObject : TenuredObject;
obj.set(ObjectGroup::newPlainObject(cx, properties.begin(), properties.length(), newKind));
if (!obj)
return false;
}
return true;
}
template bool
js::XDRObjectLiteral(XDRState<XDR_ENCODE>* xdr, MutableHandleObject obj);
template bool
js::XDRObjectLiteral(XDRState<XDR_DECODE>* xdr, MutableHandleObject obj);
JSObject*
js::CloneObjectLiteral(JSContext* cx, HandleObject srcObj)
{
if (srcObj->is<PlainObject>()) {
AllocKind kind = GetBackgroundAllocKind(gc::GetGCObjectKind(srcObj->as<PlainObject>().numFixedSlots()));
MOZ_ASSERT_IF(srcObj->isTenured(), kind == srcObj->asTenured().getAllocKind());
RootedObject proto(cx, cx->global()->getOrCreateObjectPrototype(cx));
if (!proto)
return nullptr;
RootedObjectGroup group(cx, ObjectGroup::defaultNewGroup(cx, &PlainObject::class_,
TaggedProto(proto)));
if (!group)
return nullptr;
RootedPlainObject res(cx, NewObjectWithGroup<PlainObject>(cx, group, kind,
MaybeSingletonObject));
if (!res)
return nullptr;
// XXXbz Do we still need the reshape here? We got "kind" off the
// srcObj, no? See bug 1143270.
RootedShape newShape(cx, ReshapeForAllocKind(cx, srcObj->as<PlainObject>().lastProperty(),
TaggedProto(proto), kind));
if (!newShape || !res->setLastProperty(cx, newShape))
return nullptr;
return res;
}
RootedArrayObject srcArray(cx, &srcObj->as<ArrayObject>());
MOZ_ASSERT(srcArray->denseElementsAreCopyOnWrite());
MOZ_ASSERT(srcArray->getElementsHeader()->ownerObject() == srcObj);
size_t length = srcArray->as<ArrayObject>().length();
RootedArrayObject res(cx, NewDenseFullyAllocatedArray(cx, length, NullPtr(),
MaybeSingletonObject));
if (!res)
return nullptr;
RootedId id(cx);
RootedValue value(cx);
for (size_t i = 0; i < length; i++) {
// The only markable values in copy on write arrays are atoms, which
// can be freely copied between compartments.
value = srcArray->getDenseElement(i);
MOZ_ASSERT_IF(value.isMarkable(),
value.toGCThing()->isTenured() &&
cx->runtime()->isAtomsZone(value.toGCThing()->asTenured().zoneFromAnyThread()));
id = INT_TO_JSID(i);
if (!DefineProperty(cx, res, id, value, nullptr, nullptr, JSPROP_ENUMERATE))
return nullptr;
}
if (!ObjectElements::MakeElementsCopyOnWrite(cx, res))
return nullptr;
return res;
}
void
NativeObject::fillInAfterSwap(JSContext* cx, const Vector<Value>& values, void* priv)
{
// This object has just been swapped with some other object, and its shape
// no longer reflects its allocated size. Correct this information and
// fill the slots in with the specified values.
MOZ_ASSERT(slotSpan() == values.length());
// Make sure the shape's numFixedSlots() is correct.
size_t nfixed = gc::GetGCKindSlots(asTenured().getAllocKind(), getClass());
if (nfixed != shape_->numFixedSlots()) {
if (!generateOwnShape(cx))
CrashAtUnhandlableOOM("fillInAfterSwap");
shape_->setNumFixedSlots(nfixed);
}
if (hasPrivate())
setPrivate(priv);
else
MOZ_ASSERT(!priv);
if (slots_) {
js_free(slots_);
slots_ = nullptr;
}
if (size_t ndynamic = dynamicSlotsCount(nfixed, values.length(), getClass())) {
slots_ = cx->zone()->pod_malloc<HeapSlot>(ndynamic);
if (!slots_)
CrashAtUnhandlableOOM("fillInAfterSwap");
Debug_SetSlotRangeToCrashOnTouch(slots_, ndynamic);
}
initSlotRange(0, values.begin(), values.length());
}
void
JSObject::fixDictionaryShapeAfterSwap()
{
// Dictionary shapes can point back to their containing objects, so after
// swapping the guts of those objects fix the pointers up.
if (isNative() && as<NativeObject>().inDictionaryMode())
as<NativeObject>().shape_->listp = &as<NativeObject>().shape_;
}
/* Use this method with extreme caution. It trades the guts of two objects. */
bool
JSObject::swap(JSContext* cx, HandleObject a, HandleObject b)
{
// Ensure swap doesn't cause a finalizer to not be run.
MOZ_ASSERT(IsBackgroundFinalized(a->asTenured().getAllocKind()) ==
IsBackgroundFinalized(b->asTenured().getAllocKind()));
MOZ_ASSERT(a->compartment() == b->compartment());
AutoCompartment ac(cx, a);
if (!a->getGroup(cx))
CrashAtUnhandlableOOM("JSObject::swap");
if (!b->getGroup(cx))
CrashAtUnhandlableOOM("JSObject::swap");
/*
* Neither object may be in the nursery, but ensure we update any embedded
* nursery pointers in either object.
*/
MOZ_ASSERT(!IsInsideNursery(a) && !IsInsideNursery(b));
cx->runtime()->gc.storeBuffer.putWholeCellFromMainThread(a);
cx->runtime()->gc.storeBuffer.putWholeCellFromMainThread(b);
unsigned r = NotifyGCPreSwap(a, b);
// Do the fundamental swapping of the contents of two objects.
MOZ_ASSERT(a->compartment() == b->compartment());
MOZ_ASSERT(a->is<JSFunction>() == b->is<JSFunction>());
// Don't try to swap functions with different sizes.
MOZ_ASSERT_IF(a->is<JSFunction>(), a->tenuredSizeOfThis() == b->tenuredSizeOfThis());
// Watch for oddball objects that have special organizational issues and
// can't be swapped.
MOZ_ASSERT(!a->is<RegExpObject>() && !b->is<RegExpObject>());
MOZ_ASSERT(!a->is<ArrayObject>() && !b->is<ArrayObject>());
MOZ_ASSERT(!a->is<ArrayBufferObject>() && !b->is<ArrayBufferObject>());
MOZ_ASSERT(!a->is<TypedArrayObject>() && !b->is<TypedArrayObject>());
MOZ_ASSERT(!a->is<TypedObject>() && !b->is<TypedObject>());
if (a->tenuredSizeOfThis() == b->tenuredSizeOfThis()) {
// When both objects are the same size, just do a plain swap of their
// contents.
size_t size = a->tenuredSizeOfThis();
char tmp[mozilla::tl::Max<sizeof(JSFunction), sizeof(JSObject_Slots16)>::value];
MOZ_ASSERT(size <= sizeof(tmp));
js_memcpy(tmp, a, size);
js_memcpy(a, b, size);
js_memcpy(b, tmp, size);
a->fixDictionaryShapeAfterSwap();
b->fixDictionaryShapeAfterSwap();
} else {
// Avoid GC in here to avoid confusing the tracing code with our
// intermediate state.
AutoSuppressGC suppress(cx);
// When the objects have different sizes, they will have different
// numbers of fixed slots before and after the swap, so the slots for
// native objects will need to be rearranged.
NativeObject* na = a->isNative() ? &a->as<NativeObject>() : nullptr;
NativeObject* nb = b->isNative() ? &b->as<NativeObject>() : nullptr;
// Remember the original values from the objects.
Vector<Value> avals(cx);
void* apriv = nullptr;
if (na) {
apriv = na->hasPrivate() ? na->getPrivate() : nullptr;
for (size_t i = 0; i < na->slotSpan(); i++) {
if (!avals.append(na->getSlot(i)))
CrashAtUnhandlableOOM("JSObject::swap");
}
}
Vector<Value> bvals(cx);
void* bpriv = nullptr;
if (nb) {
bpriv = nb->hasPrivate() ? nb->getPrivate() : nullptr;
for (size_t i = 0; i < nb->slotSpan(); i++) {
if (!bvals.append(nb->getSlot(i)))
CrashAtUnhandlableOOM("JSObject::swap");
}
}
// Swap the main fields of the objects, whether they are native objects or proxies.
char tmp[sizeof(JSObject_Slots0)];
js_memcpy(&tmp, a, sizeof tmp);
js_memcpy(a, b, sizeof tmp);
js_memcpy(b, &tmp, sizeof tmp);
a->fixDictionaryShapeAfterSwap();
b->fixDictionaryShapeAfterSwap();
if (na)
b->as<NativeObject>().fillInAfterSwap(cx, avals, apriv);
if (nb)
a->as<NativeObject>().fillInAfterSwap(cx, bvals, bpriv);
}
// Swapping the contents of two objects invalidates type sets which contain
// either of the objects, so mark all such sets as unknown.
MarkObjectGroupUnknownProperties(cx, a->group());
MarkObjectGroupUnknownProperties(cx, b->group());
/*
* 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.
*/
JS::Zone* zone = a->zone();
if (zone->needsIncrementalBarrier()) {
a->markChildren(zone->barrierTracer());
b->markChildren(zone->barrierTracer());
}
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.
*/
Rooted<GlobalObject*> global(cx, &obj->as<GlobalObject>());
if (!global->lookup(cx, id)) {
global->setConstructorPropertySlot(key, v);
uint32_t slot = GlobalObject::constructorPropertySlot(key);
if (!NativeObject::addProperty(cx, global, id, nullptr, nullptr, slot, attrs, 0))
return false;
named = true;
return true;
}
}
named = DefineProperty(cx, obj, id, v, nullptr, nullptr, attrs);
return named;
}
static void
SetClassObject(JSObject* obj, JSProtoKey key, JSObject* cobj, JSObject* proto)
{
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)
{
if (!obj->is<GlobalObject>())
return;
obj->as<GlobalObject>().setConstructor(key, UndefinedValue());
obj->as<GlobalObject>().setPrototype(key, UndefinedValue());
}
static NativeObject*
DefineConstructorAndPrototype(JSContext* cx, HandleObject obj, JSProtoKey key, HandleAtom atom,
HandleObject protoProto, const Class* clasp,
Native constructor, unsigned nargs,
const JSPropertySpec* ps, const JSFunctionSpec* fs,
const JSPropertySpec* static_ps, const JSFunctionSpec* static_fs,
NativeObject** 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 won't let us use protoProto as the proto.
*/
RootedNativeObject proto(cx, NewNativeObjectWithClassProto(cx, clasp, protoProto, SingletonObject));
if (!proto)
return nullptr;
/* After this point, control must exit via label bad or out. */
RootedNativeObject 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 {
RootedFunction fun(cx, NewNativeConstructor(cx, constructor, nargs, atom, ctorKind));
if (!fun)
goto bad;
/*
* Set the class object early for standard class constructors. Type
* inference may need to access these, and js::GetBuiltinPrototype 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 (!DefinePropertiesAndFunctions(cx, proto, ps, fs) ||
(ctor != proto && !DefinePropertiesAndFunctions(cx, ctor, static_ps, static_fs)))
{
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) {
ObjectOpResult ignored;
RootedId id(cx, AtomToId(atom));
// XXX FIXME - absurd to call this here; instead define the property last.
DeleteProperty(cx, obj, id, ignored);
}
if (cached)
ClearClassObject(obj, key);
return nullptr;
}
NativeObject*
js::InitClass(JSContext* cx, HandleObject obj, HandleObject protoProto_,
const Class* clasp, Native constructor, unsigned nargs,
const JSPropertySpec* ps, const JSFunctionSpec* fs,
const JSPropertySpec* static_ps, const JSFunctionSpec* static_fs,
NativeObject** ctorp, AllocKind ctorKind)
{
RootedObject protoProto(cx, protoProto_);
/* Check function pointer members. */
MOZ_ASSERT(clasp->addProperty != JS_PropertyStub);
MOZ_ASSERT(clasp->getProperty != JS_PropertyStub);
MOZ_ASSERT(clasp->setProperty != JS_StrictPropertyStub);
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 Object.prototype. The engine's internal uses of
* js::InitClass depend on this nicety.
*/
JSProtoKey key = JSCLASS_CACHED_PROTO_KEY(clasp);
if (key != JSProto_Null &&
!protoProto &&
!GetBuiltinPrototype(cx, JSProto_Object, &protoProto))
{
return nullptr;
}
return DefineConstructorAndPrototype(cx, obj, key, atom, protoProto, clasp, constructor, nargs,
ps, fs, static_ps, static_fs, ctorp, ctorKind);
}
void
JSObject::fixupAfterMovingGC()
{
// For copy-on-write objects that don't own their elements, fix up the
// elements pointer if it points to inline elements in the owning object.
if (is<NativeObject>()) {
NativeObject& obj = as<NativeObject>();
if (obj.denseElementsAreCopyOnWrite()) {
NativeObject* owner = MaybeForwarded(obj.getElementsHeader()->ownerObject().get());
if (owner != &obj && owner->hasFixedElements())
obj.elements_ = owner->getElementsHeader()->elements();
MOZ_ASSERT(!IsForwarded(obj.getElementsHeader()->ownerObject().get()));
}
}
}
bool
js::SetClassAndProto(JSContext* cx, HandleObject obj,
const Class* clasp, Handle<js::TaggedProto> proto)
{
// Regenerate the object's shape. If the object is a proto (isDelegate()),
// we also need to regenerate shapes for all of the objects 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
// 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.
RootedObject oldproto(cx, obj);
while (oldproto && oldproto->isNative()) {
if (oldproto->isSingleton()) {
if (!oldproto->as<NativeObject>().generateOwnShape(cx))
return false;
} else {
if (!oldproto->setUncacheableProto(cx))
return false;
}
if (!obj->isDelegate()) {
// If |obj| is not a proto of another object, we don't need to
// reshape the whole proto chain.
MOZ_ASSERT(obj == oldproto);
break;
}
oldproto = oldproto->getProto();
}
if (proto.isObject() && !proto.toObject()->setDelegate(cx))
return false;
if (obj->isSingleton()) {
/*
* Just splice the prototype, but mark the properties as unknown for
* consistent behavior.
*/
if (!obj->splicePrototype(cx, clasp, proto))
return false;
MarkObjectGroupUnknownProperties(cx, obj->group());
return true;
}
if (proto.isObject()) {
RootedObject protoObj(cx, proto.toObject());
if (!JSObject::setNewGroupUnknown(cx, clasp, protoObj))
return false;
}
ObjectGroup* group = ObjectGroup::defaultNewGroup(cx, clasp, proto);
if (!group)
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 treat all such
* type sets as unknown.
*/
MarkObjectGroupUnknownProperties(cx, obj->group());
MarkObjectGroupUnknownProperties(cx, group);
obj->setGroup(group);
return true;
}
static bool
MaybeResolveConstructor(ExclusiveContext* cxArg, Handle<GlobalObject*> global, JSProtoKey key)
{
if (global->isStandardClassResolved(key))
return true;
if (!cxArg->shouldBeJSContext())
return false;
JSContext* cx = cxArg->asJSContext();
return GlobalObject::resolveConstructor(cx, global, key);
}
bool
js::GetBuiltinConstructor(ExclusiveContext* cx, JSProtoKey key, MutableHandleObject objp)
{
MOZ_ASSERT(key != JSProto_Null);
Rooted<GlobalObject*> global(cx, cx->global());
if (!MaybeResolveConstructor(cx, global, key))
return false;
objp.set(&global->getConstructor(key).toObject());
return true;
}
bool
js::GetBuiltinPrototype(ExclusiveContext* cx, JSProtoKey key, MutableHandleObject protop)
{
MOZ_ASSERT(key != JSProto_Null);
Rooted<GlobalObject*> global(cx, cx->global());
if (!MaybeResolveConstructor(cx, global, key))
return false;
protop.set(&global->getPrototype(key).toObject());
return true;
}
static bool
IsStandardPrototype(JSObject* obj, JSProtoKey key)
{
GlobalObject& global = obj->global();
Value v = global.getPrototype(key);
return v.isObject() && obj == &v.toObject();
}
JSProtoKey
JS::IdentifyStandardInstance(JSObject* obj)
{
// Note: The prototype shares its JSClass with instances.
MOZ_ASSERT(!obj->is<CrossCompartmentWrapperObject>());
JSProtoKey key = StandardProtoKeyOrNull(obj);
if (key != JSProto_Null && !IsStandardPrototype(obj, key))
return key;
return JSProto_Null;
}
JSProtoKey
JS::IdentifyStandardPrototype(JSObject* obj)
{
// Note: The prototype shares its JSClass with instances.
MOZ_ASSERT(!obj->is<CrossCompartmentWrapperObject>());
JSProtoKey key = StandardProtoKeyOrNull(obj);
if (key != JSProto_Null && IsStandardPrototype(obj, key))
return key;
return JSProto_Null;
}
JSProtoKey
JS::IdentifyStandardInstanceOrPrototype(JSObject* obj)
{
return StandardProtoKeyOrNull(obj);
}
JSProtoKey
JS::IdentifyStandardConstructor(JSObject* obj)
{
// Note that NATIVE_CTOR does not imply that we are a standard constructor,
// but the converse is true (at least until we start having self-hosted
// constructors for standard classes). This lets us avoid a costly loop for
// many functions (which, depending on the call site, may be the common case).
if (!obj->is<JSFunction>() || !(obj->as<JSFunction>().flags() & JSFunction::NATIVE_CTOR))
return JSProto_Null;
GlobalObject& global = obj->global();
for (size_t k = 0; k < JSProto_LIMIT; ++k) {
JSProtoKey key = static_cast<JSProtoKey>(k);
if (global.getConstructor(key) == ObjectValue(*obj))
return key;
}
return JSProto_Null;
}
bool
JSObject::isCallable() const
{
if (is<JSFunction>())
return true;
return callHook() != nullptr;
}
bool
JSObject::isConstructor() const
{
if (is<JSFunction>()) {
const JSFunction& fun = as<JSFunction>();
return fun.isNativeConstructor() || fun.isInterpretedConstructor();
}
return constructHook() != nullptr;
}
JSNative
JSObject::callHook() const
{
const js::Class* clasp = getClass();
if (clasp->call)
return clasp->call;
if (is<js::ProxyObject>()) {
const js::ProxyObject& p = as<js::ProxyObject>();
if (p.handler()->isCallable(const_cast<JSObject*>(this)))
return js::proxy_Call;
}
return nullptr;
}
JSNative
JSObject::constructHook() const
{
const js::Class* clasp = getClass();
if (clasp->construct)
return clasp->construct;
if (is<js::ProxyObject>()) {
const js::ProxyObject& p = as<js::ProxyObject>();
if (p.handler()->isConstructor(const_cast<JSObject*>(this)))
return js::proxy_Construct;
}
return nullptr;
}
bool
js::LookupProperty(JSContext* cx, HandleObject obj, js::HandleId id,
MutableHandleObject objp, MutableHandleShape propp)
{
/* NB: The logic of lookupProperty is implicitly reflected in
* BaselineIC.cpp's |EffectlesslyLookupProperty| logic.
* If this changes, please remember to update the logic there as well.
*/
if (LookupPropertyOp op = obj->getOps()->lookupProperty)
return op(cx, obj, id, objp, propp);
return NativeLookupProperty<CanGC>(cx, obj.as<NativeObject>(), id, 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 (!LookupProperty(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);
MOZ_ASSERT(!*objp && !*pobjp && !*propp);
for (JSObject* scope = scopeChain; scope; scope = scope->enclosingScope()) {
if (scope->getOps()->lookupProperty)
return false;
if (!LookupPropertyInline<NoGC>(cx, &scope->as<NativeObject>(), NameToId(name), 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 shape(cx);
RootedObject scope(cx, scopeChain);
for (; !scope->is<GlobalObject>(); scope = scope->enclosingScope()) {
if (!LookupProperty(cx, scope, id, &pobj, &shape))
return false;
if (shape)
break;
}
objp.set(scope);
return true;
}
bool
js::LookupNameUnqualified(JSContext* cx, HandlePropertyName name, HandleObject scopeChain,
MutableHandleObject objp)
{
RootedId id(cx, NameToId(name));
RootedObject pobj(cx);
RootedShape shape(cx);
RootedObject scope(cx, scopeChain);
for (; !scope->isUnqualifiedVarObj(); scope = scope->enclosingScope()) {
if (!LookupProperty(cx, scope, id, &pobj, &shape))
return false;
if (shape)
break;
}
// See note above UninitializedLexicalObject.
if (pobj == scope && IsUninitializedLexicalSlot(scope, shape)) {
scope = UninitializedLexicalObject::create(cx, scope);
if (!scope)
return false;
}
objp.set(scope);
return true;
}
bool
js::HasOwnProperty(JSContext* cx, HandleObject obj, HandleId id, bool* result)
{
if (obj->is<ProxyObject>())
return Proxy::hasOwn(cx, obj, id, result);
if (GetOwnPropertyOp op = obj->getOps()->getOwnPropertyDescriptor) {
Rooted<PropertyDescriptor> desc(cx);
if (!op(cx, obj, id, &desc))
return false;
*result = !!desc.object();
return true;
}
RootedShape shape(cx);
if (!NativeLookupOwnProperty<CanGC>(cx, obj.as<NativeObject>(), id, &shape))
return false;
*result = (shape != nullptr);
return true;
}
bool
js::LookupPropertyPure(ExclusiveContext* cx, JSObject* obj, jsid id, JSObject** objp,
Shape** propp)
{
do {
if (obj->isNative()) {
/* Search for a native dense element, typed array element, or property. */
if (JSID_IS_INT(id) && obj->as<NativeObject>().containsDenseElement(JSID_TO_INT(id))) {
*objp = obj;
MarkDenseOrTypedArrayElementFound<NoGC>(propp);
return true;
}
if (IsAnyTypedArray(obj)) {
uint64_t index;
if (IsTypedArrayIndex(id, &index)) {
if (index < AnyTypedArrayLength(obj)) {
*objp = obj;
MarkDenseOrTypedArrayElementFound<NoGC>(propp);
} else {
*objp = nullptr;
*propp = nullptr;
}
return true;
}
}
if (Shape* shape = obj->as<NativeObject>().lookupPure(id)) {
*objp = obj;
*propp = shape;
return true;
}
// Fail if there's a resolve hook. We allow the JSFunction resolve hook
// if we know it will never add a property with this name or str_resolve
// with a non-integer property.
do {
const Class* clasp = obj->getClass();
if (!clasp->resolve)
break;
if (clasp->resolve == fun_resolve && !FunctionHasResolveHook(cx->names(), id))
break;
if (clasp->resolve == str_resolve && !JSID_IS_INT(id))
break;
return false;
} while (0);
} else if (obj->is<UnboxedPlainObject>()) {
if (obj->as<UnboxedPlainObject>().containsUnboxedOrExpandoProperty(cx, id)) {
*objp = obj;
MarkNonNativePropertyFound<NoGC>(propp);
return true;
}
} else if (obj->is<TypedObject>()) {
if (obj->as<TypedObject>().typeDescr().hasProperty(cx->names(), id)) {
*objp = obj;
MarkNonNativePropertyFound<NoGC>(propp);
return true;
}
} else {
return false;
}
obj = obj->getProto();
} while (obj);
*objp = nullptr;
*propp = nullptr;
return true;
}
bool
js::GetPropertyPure(ExclusiveContext* cx, JSObject* obj, jsid id, Value* vp)
{
JSObject* pobj;
Shape* shape;
if (!LookupPropertyPure(cx, obj, id, &pobj, &shape))
return false;
return pobj->isNative() && NativeGetPureInline(&pobj->as<NativeObject>(), shape, vp);
}
bool
JSObject::reportReadOnly(JSContext* cx, jsid id, unsigned report)
{
RootedValue val(cx, IdToValue(id));
return ReportValueErrorFlags(cx, report, JSMSG_READ_ONLY,
JSDVG_IGNORE_STACK, val, js::NullPtr(),
nullptr, nullptr);
}
bool
JSObject::reportNotConfigurable(JSContext* cx, jsid id, unsigned report)
{
RootedValue val(cx, IdToValue(id));
return ReportValueErrorFlags(cx, report, JSMSG_CANT_DELETE,
JSDVG_IGNORE_STACK, val, js::NullPtr(),
nullptr, nullptr);
}
bool
JSObject::reportNotExtensible(JSContext* cx, unsigned report)
{
RootedValue val(cx, ObjectValue(*this));
return ReportValueErrorFlags(cx, report, JSMSG_OBJECT_NOT_EXTENSIBLE,
JSDVG_IGNORE_STACK, val, js::NullPtr(),
nullptr, nullptr);
}
/*** ES6 standard internal methods ***************************************************************/
bool
js::SetPrototype(JSContext* cx, HandleObject obj, HandleObject proto, JS::ObjectOpResult& result)
{
/*
* If |obj| has a "lazy" [[Prototype]], it is 1) a proxy 2) whose handler's
* {get,set}Prototype and setImmutablePrototype methods mediate access to
* |obj.[[Prototype]]|. The Proxy subsystem is responsible for responding
* to such attempts.
*/
if (obj->hasLazyPrototype()) {
MOZ_ASSERT(obj->is<ProxyObject>());
return Proxy::setPrototype(cx, obj, proto, result);
}
/* Disallow mutation of immutable [[Prototype]]s. */
if (obj->nonLazyPrototypeIsImmutable()) {
return result.fail(JSMSG_CANT_SET_PROTO);
}
/*
* Disallow mutating the [[Prototype]] on ArrayBuffer objects, which
* due to their complicated delegate-object shenanigans can't easily
* have a mutable [[Prototype]].
*/
if (obj->is<ArrayBufferObject>()) {
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_CANT_SET_PROTO_OF,
"incompatible ArrayBuffer");
return false;
}
/*
* Disallow mutating the [[Prototype]] on Typed Objects, per the spec.
*/
if (obj->is<TypedObject>()) {
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_CANT_SET_PROTO_OF,
"incompatible TypedObject");
return false;
}
/*
* Explicitly disallow mutating the [[Prototype]] of Location objects
* for flash-related security reasons.
*/
if (!strcmp(obj->getClass()->name, "Location")) {
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_CANT_SET_PROTO_OF,
"incompatible Location object");
return false;
}
/* ES6 9.1.2 step 5 forbids changing [[Prototype]] if not [[Extensible]]. */
bool extensible;
if (!IsExtensible(cx, obj, &extensible))
return false;
if (!extensible)
return result.fail(JSMSG_CANT_SET_PROTO);
/* ES6 9.1.2 step 6 forbids generating cyclical prototype chains. */
RootedObject obj2(cx);
for (obj2 = proto; obj2; ) {
if (obj2 == obj)
return result.fail(JSMSG_CANT_SET_PROTO_CYCLE);
if (!GetPrototype(cx, obj2, &obj2))
return false;
}
// Convert unboxed objects to their native representations before changing
// their prototype/group, as they depend on the group for their layout.
if (obj->is<UnboxedPlainObject>() && !UnboxedPlainObject::convertToNative(cx, obj))
return false;
Rooted<TaggedProto> taggedProto(cx, TaggedProto(proto));
if (!SetClassAndProto(cx, obj, obj->getClass(), taggedProto))
return false;
return result.succeed();
}
bool
js::SetPrototype(JSContext* cx, HandleObject obj, HandleObject proto)
{
ObjectOpResult result;
return SetPrototype(cx, obj, proto, result) && result.checkStrict(cx, obj);
}
bool
js::PreventExtensions(JSContext* cx, HandleObject obj, ObjectOpResult& result)
{
if (obj->is<ProxyObject>())
return js::Proxy::preventExtensions(cx, obj, result);
if (!obj->nonProxyIsExtensible())
return result.succeed();
// Force lazy properties to be resolved.
AutoIdVector props(cx);
if (!js::GetPropertyKeys(cx, obj, JSITER_HIDDEN | JSITER_OWNONLY, &props))
return false;
// Convert all dense elements to sparse properties. This will shrink the
// initialized length and capacity of the object to zero and ensure that no
// new dense elements can be added without calling growElements(), which
// checks isExtensible().
if (obj->isNative()) {
if (!NativeObject::sparsifyDenseElements(cx, obj.as<NativeObject>()))
return false;
}
if (!obj->setFlags(cx, BaseShape::NOT_EXTENSIBLE, JSObject::GENERATE_SHAPE))
return false;
return result.succeed();
}
bool
js::PreventExtensions(JSContext* cx, HandleObject obj)
{
ObjectOpResult result;
return PreventExtensions(cx, obj, result) && result.checkStrict(cx, obj);
}
bool
js::GetOwnPropertyDescriptor(JSContext* cx, HandleObject obj, HandleId id,
MutableHandle<PropertyDescriptor> desc)
{
if (GetOwnPropertyOp op = obj->getOps()->getOwnPropertyDescriptor)
return op(cx, obj, id, desc);
RootedShape shape(cx);
if (!NativeLookupOwnProperty<CanGC>(cx, obj.as<NativeObject>(), id, &shape))
return false;
if (!shape) {
desc.object().set(nullptr);
return true;
}
bool doGet = true;
desc.setAttributes(GetShapeAttributes(obj, shape));
if (desc.isAccessorDescriptor()) {
MOZ_ASSERT(desc.isShared());
doGet = false;
// The result of GetOwnPropertyDescriptor() must be either undefined or
// a complete property descriptor (per ES6 draft rev 32 (2015 Feb 2)
// 6.1.7.3, Invariants of the Essential Internal Methods).
//
// It is an unfortunate fact that in SM, properties can exist that have
// JSPROP_GETTER or JSPROP_SETTER but not both. In these cases, rather
// than return true with desc incomplete, we fill out the missing
// getter or setter with a null, following CompletePropertyDescriptor.
if (desc.hasGetterObject()) {
desc.setGetterObject(shape->getterObject());
} else {
desc.setGetterObject(nullptr);
desc.attributesRef() |= JSPROP_GETTER;
}
if (desc.hasSetterObject()) {
desc.setSetterObject(shape->setterObject());
} else {
desc.setSetterObject(nullptr);
desc.attributesRef() |= JSPROP_SETTER;
}
} else {
// This is either a straight-up data property or (rarely) a
// property with a JSGetterOp/JSSetterOp. The latter must be
// reported to the caller as a plain data property, so don't
// populate desc.getter/setter, and mask away the SHARED bit.
desc.attributesRef() &= ~JSPROP_SHARED;
}
RootedValue value(cx);
if (doGet && !GetProperty(cx, obj, obj, id, &value))
return false;
desc.value().set(value);
desc.object().set(obj);
return true;
}
bool
js::DefineProperty(JSContext* cx, HandleObject obj, HandleId id, Handle<PropertyDescriptor> desc,
ObjectOpResult& result)
{
if (DefinePropertyOp op = obj->getOps()->defineProperty)
return op(cx, obj, id, desc, result);
return NativeDefineProperty(cx, obj.as<NativeObject>(), id, desc, result);
}
bool
js::DefineProperty(ExclusiveContext* cx, HandleObject obj, HandleId id, HandleValue value,
JSGetterOp getter, JSSetterOp setter, unsigned attrs,
ObjectOpResult& result)
{
MOZ_ASSERT(!(attrs & JSPROP_PROPOP_ACCESSORS));
Rooted<PropertyDescriptor> desc(cx);
desc.initFields(obj, value, attrs, getter, setter);
if (DefinePropertyOp op = obj->getOps()->defineProperty) {
if (!cx->shouldBeJSContext())
return false;
return op(cx->asJSContext(), obj, id, desc, result);
}
return NativeDefineProperty(cx, obj.as<NativeObject>(), id, desc, result);
}
bool
js::DefineProperty(ExclusiveContext* cx, HandleObject obj, PropertyName* name, HandleValue value,
JSGetterOp getter, JSSetterOp setter, unsigned attrs,
ObjectOpResult& result)
{
RootedId id(cx, NameToId(name));
return DefineProperty(cx, obj, id, value, getter, setter, attrs, result);
}
bool
js::DefineElement(ExclusiveContext* cx, HandleObject obj, uint32_t index, HandleValue value,
JSGetterOp getter, JSSetterOp setter, unsigned attrs,
ObjectOpResult& result)
{
MOZ_ASSERT(getter != JS_PropertyStub);
MOZ_ASSERT(setter != JS_StrictPropertyStub);
RootedId id(cx);
if (!IndexToId(cx, index, &id))
return false;
return DefineProperty(cx, obj, id, value, getter, setter, attrs, result);
}
bool
js::DefineProperty(ExclusiveContext* cx, HandleObject obj, HandleId id, HandleValue value,
JSGetterOp getter, JSSetterOp setter, unsigned attrs)
{
ObjectOpResult result;
if (!DefineProperty(cx, obj, id, value, getter, setter, attrs, result))
return false;
if (!result) {
if (!cx->shouldBeJSContext())
return false;
result.reportError(cx->asJSContext(), obj, id);
return false;
}
return true;
}
bool
js::DefineProperty(ExclusiveContext* cx, HandleObject obj, PropertyName* name, HandleValue value,
JSGetterOp getter, JSSetterOp setter, unsigned attrs)
{
RootedId id(cx, NameToId(name));
return DefineProperty(cx, obj, id, value, getter, setter, attrs);
}
bool
js::DefineElement(ExclusiveContext* cx, HandleObject obj, uint32_t index, HandleValue value,
JSGetterOp getter, JSSetterOp setter, unsigned attrs)
{
MOZ_ASSERT(getter != JS_PropertyStub);
MOZ_ASSERT(setter != JS_StrictPropertyStub);
RootedId id(cx);
if (!IndexToId(cx, index, &id))
return false;
return DefineProperty(cx, obj, id, value, getter, setter, attrs);
}
/*** SpiderMonkey nonstandard internal methods ***************************************************/
bool
js::SetImmutablePrototype(ExclusiveContext* cx, HandleObject obj, bool* succeeded)
{
if (obj->hasLazyPrototype()) {
if (!cx->shouldBeJSContext())
return false;
return Proxy::setImmutablePrototype(cx->asJSContext(), obj, succeeded);
}
if (!obj->setFlags(cx, BaseShape::IMMUTABLE_PROTOTYPE))
return false;
*succeeded = true;
return true;
}
bool
js::GetPropertyDescriptor(JSContext* cx, HandleObject obj, HandleId id,
MutableHandle<PropertyDescriptor> desc)
{
RootedObject pobj(cx);
for (pobj = obj; pobj;) {
if (pobj->is<ProxyObject>())
return Proxy::getPropertyDescriptor(cx, pobj, id, desc);
if (!GetOwnPropertyDescriptor(cx, pobj, id, desc))
return false;
if (desc.object())
return true;
if (!GetPrototype(cx, pobj, &pobj))
return false;
}
MOZ_ASSERT(!desc.object());
return true;
}
bool
js::ToPrimitive(JSContext* cx, HandleObject obj, JSType hint, MutableHandleValue vp)
{
bool ok;
if (JSConvertOp op = obj->getClass()->convert)
ok = op(cx, obj, hint, vp);
else
ok = JS::OrdinaryToPrimitive(cx, obj, hint, vp);
MOZ_ASSERT_IF(ok, vp.isPrimitive());
return ok;
}
bool
js::WatchGuts(JSContext* cx, JS::HandleObject origObj, JS::HandleId id, JS::HandleObject callable)
{
RootedObject obj(cx, GetInnerObject(origObj));
if (obj->isNative()) {
// Use sparse indexes for watched objects, as dense elements can be
// written to without checking the watchpoint map.
if (!NativeObject::sparsifyDenseElements(cx, obj.as<NativeObject>()))
return false;
MarkTypePropertyNonData(cx, obj, id);
}
WatchpointMap* wpmap = cx->compartment()->watchpointMap;
if (!wpmap) {
wpmap = cx->runtime()->new_<WatchpointMap>();
if (!wpmap || !wpmap->init()) {
ReportOutOfMemory(cx);
return false;
}
cx->compartment()->watchpointMap = wpmap;
}
return wpmap->watch(cx, obj, id, js::WatchHandler, 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(origObj));
if (WatchpointMap* wpmap = cx->compartment()->watchpointMap)
wpmap->unwatch(obj, id, nullptr, nullptr);
return true;
}
bool
js::WatchProperty(JSContext* cx, HandleObject obj, HandleId id, HandleObject callable)
{
if (WatchOp op = obj->getOps()->watch)
return op(cx, obj, id, callable);
if (!obj->isNative() || IsAnyTypedArray(obj)) {
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_CANT_WATCH,
obj->getClass()->name);
return false;
}
return WatchGuts(cx, obj, id, callable);
}
bool
js::UnwatchProperty(JSContext* cx, HandleObject obj, HandleId id)
{
if (UnwatchOp op = obj->getOps()->unwatch)
return op(cx, obj, id);
return UnwatchGuts(cx, obj, id);
}
const char*
js::GetObjectClassName(JSContext* cx, HandleObject obj)
{
assertSameCompartment(cx, obj);
if (obj->is<ProxyObject>())
return Proxy::className(cx, obj);
return obj->getClass()->name;
}
bool
JSObject::callMethod(JSContext* cx, HandleId id, unsigned argc, Value* argv, MutableHandleValue vp)
{
RootedValue fval(cx);
RootedObject obj(cx, this);
if (!GetProperty(cx, obj, obj, id, &fval))
return false;
return Invoke(cx, ObjectValue(*obj), fval, argc, argv, vp);
}
/* * */
bool
js::HasDataProperty(JSContext* cx, NativeObject* 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->lookup(cx, id)) {
if (shape->hasDefaultGetter() && shape->hasSlot()) {
*vp = obj->getSlot(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 (!GetProperty(cx, obj, obj, id, vp))
return false;
if (!IsCallable(vp)) {
vp.setObject(*obj);
return true;
}
return Invoke(cx, ObjectValue(*obj), vp, 0, nullptr, vp);
}
bool
JS::OrdinaryToPrimitive(JSContext* cx, HandleObject obj, JSType hint, MutableHandleValue vp)
{
MOZ_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_) {
StringObject* nobj = &obj->as<StringObject>();
if (ClassMethodIsNative(cx, nobj, &StringObject::class_, id, str_toString)) {
vp.setString(nobj->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);
StringObject* nobj = &obj->as<StringObject>();
if (ClassMethodIsNative(cx, nobj, &StringObject::class_, id, str_toString)) {
vp.setString(nobj->unbox());
return true;
}
}
/* Optimize new Number(...).valueOf(). */
if (clasp == &NumberObject::class_) {
id = NameToId(cx->names().valueOf);
NumberObject* nobj = &obj->as<NumberObject>();
if (ClassMethodIsNative(cx, nobj, &NumberObject::class_, id, num_valueOf)) {
vp.setNumber(nobj->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 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));
ReportValueError2(cx, JSMSG_CANT_CONVERT_TO, JSDVG_SEARCH_STACK, val, str,
hint == JSTYPE_VOID
? "primitive type"
: hint == JSTYPE_STRING ? "string" : "number");
return false;
}
bool
js::IsDelegate(JSContext* cx, HandleObject obj, const js::Value& v, bool* result)
{
if (v.isPrimitive()) {
*result = false;
return true;
}
return IsDelegateOfObject(cx, obj, &v.toObject(), result);
}
bool
js::IsDelegateOfObject(JSContext* cx, HandleObject protoObj, JSObject* obj, bool* result)
{
RootedObject obj2(cx, obj);
for (;;) {
if (!GetPrototype(cx, obj2, &obj2))
return false;
if (!obj2) {
*result = false;
return true;
}
if (obj2 == protoObj) {
*result = true;
return true;
}
}
}
JSObject*
js::GetBuiltinPrototypePure(GlobalObject* global, JSProtoKey protoKey)
{
MOZ_ASSERT(JSProto_Null <= protoKey);
MOZ_ASSERT(protoKey < JSProto_LIMIT);
if (protoKey != JSProto_Null) {
const Value& v = global->getPrototype(protoKey);
if (v.isObject())
return &v.toObject();
}
return nullptr;
}
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());
if (v.isBoolean())
return BooleanObject::create(cx, v.toBoolean());
MOZ_ASSERT(v.isSymbol());
RootedSymbol symbol(cx, v.toSymbol());
return SymbolObject::create(cx, symbol);
}
/*
* Invokes the ES5 ToObject algorithm on vp, returning the result. If vp might
* already be an object, use ToObject. reportCantConvert controls how null and
* undefined errors are reported.
*
* Callers must handle the already-object case.
*/
JSObject*
js::ToObjectSlow(JSContext* cx, JS::HandleValue val, bool reportScanStack)
{
MOZ_ASSERT(!val.isMagic());
MOZ_ASSERT(!val.isObject());
if (val.isNullOrUndefined()) {
if (reportScanStack) {
ReportIsNullOrUndefined(cx, JSDVG_SEARCH_STACK, val, NullPtr());
} else {
JS_ReportErrorNumber(cx, 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)
{
MOZ_ASSERT(trc->debugPrinter() == GetObjectSlotName);
JSObject* obj = (JSObject*)trc->debugPrintArg();
uint32_t slot = uint32_t(trc->debugPrintIndex());
Shape* shape;
if (obj->isNative()) {
shape = obj->as<NativeObject>().lastProperty();
while (shape && (!shape->hasSlot() || shape->slot() != slot))
shape = shape->previous();
} else {
shape = nullptr;
}
if (!shape) {
do {
const char* slotname = nullptr;
const char* pattern = nullptr;
if (obj->is<GlobalObject>()) {
pattern = "CLASS_OBJECT(%s)";
if (false)
;
#define TEST_SLOT_MATCHES_PROTOTYPE(name,code,init,clasp) \
else if ((code) == slot) { slotname = js_##name##_str; }
JS_FOR_EACH_PROTOTYPE(TEST_SLOT_MATCHES_PROTOTYPE)
#undef TEST_SLOT_MATCHES_PROTOTYPE
} else {
pattern = "%s";
if (obj->is<ScopeObject>()) {
if (slot == ScopeObject::enclosingScopeSlot()) {
slotname = "enclosing_environment";
} else if (obj->is<CallObject>()) {
if (slot == CallObject::calleeSlot())
slotname = "callee_slot";
} else if (obj->is<DeclEnvObject>()) {
if (slot == DeclEnvObject::lambdaSlot())
slotname = "named_lambda";
} else if (obj->is<DynamicWithObject>()) {
if (slot == DynamicWithObject::objectSlot())
slotname = "with_object";
else if (slot == DynamicWithObject::thisSlot())
slotname = "with_this";
}
}
}
if (slotname)
JS_snprintf(buf, bufsize, pattern, slotname);
else
JS_snprintf(buf, bufsize, "**UNKNOWN SLOT %ld**", (long)slot);
} while (false);
} 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 if (JSID_IS_SYMBOL(propid)) {
JS_snprintf(buf, bufsize, "**SYMBOL KEY**");
} 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,
GetErrorMessage, nullptr,
JSMSG_GETTER_ONLY);
}
/*** Debugging routines **************************************************************************/
#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.isSymbol())
v.toSymbol()->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:%" PRIuSIZE ")",
script->filename() ? script->filename() : "", 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 == &PlainObject::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_NO_ITER_VALUE: fprintf(stderr, " no iter value"); break;
case JS_GENERATOR_CLOSING: fprintf(stderr, " generator closing"); break;
case JS_OPTIMIZED_OUT: fprintf(stderr, " optimized out"); 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(NativeObject* obj, Shape& shape)
{
jsid id = shape.propid();
uint8_t attrs = shape.attributes();
fprintf(stderr, " ((js::Shape*) %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_IS_INT(id) || JSID_IS_SYMBOL(id))
dumpValue(js::IdToValue(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
{
return is<ProxyObject>();
}
void
JSObject::dump()
{
JSObject* obj = this;
JSObject* globalObj = &global();
fprintf(stderr, "object %p from global %p [%s]\n", (void*) obj,
(void*) globalObj, globalObj->getClass()->name);
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->isBoundFunction()) fprintf(stderr, " bound_function");
if (obj->isQualifiedVarObj()) fprintf(stderr, " varobj");
if (obj->isUnqualifiedVarObj()) fprintf(stderr, " unqualified_varobj");
if (obj->watched()) fprintf(stderr, " watched");
if (obj->isIteratedSingleton()) fprintf(stderr, " iterated_singleton");
if (obj->isNewGroupUnknown()) fprintf(stderr, " new_type_unknown");
if (obj->hasUncacheableProto()) fprintf(stderr, " has_uncacheable_proto");
if (obj->hadElementsAccess()) fprintf(stderr, " had_elements_access");
if (obj->wasNewScriptCleared()) fprintf(stderr, " new_script_cleared");
if (obj->isNative()) {
NativeObject* nobj = &obj->as<NativeObject>();
if (nobj->inDictionaryMode())
fprintf(stderr, " inDictionaryMode");
if (nobj->hasShapeTable())
fprintf(stderr, " hasShapeTable");
}
fprintf(stderr, "\n");
if (obj->isNative()) {
NativeObject* nobj = &obj->as<NativeObject>();
uint32_t slots = nobj->getDenseInitializedLength();
if (slots) {
fprintf(stderr, "elements\n");
for (uint32_t i = 0; i < slots; i++) {
fprintf(stderr, " %3d: ", i);
dumpValue(nobj->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);
if (clasp->flags & JSCLASS_HAS_PRIVATE)
fprintf(stderr, "private %p\n", obj->as<NativeObject>().getPrivate());
if (!obj->isNative())
fprintf(stderr, "not native\n");
uint32_t reservedEnd = JSCLASS_RESERVED_SLOTS(clasp);
uint32_t slots = obj->isNative() ? obj->as<NativeObject>().slotSpan() : 0;
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->as<NativeObject>().getSlot(i));
fputc('\n', stderr);
}
if (obj->isNative()) {
fprintf(stderr, "properties:\n");
Vector<Shape*, 8, SystemAllocPolicy> props;
for (Shape::Range<NoGC> r(obj->as<NativeObject>().lastProperty()); !r.empty(); r.popFront())
props.append(&r.front());
for (size_t i = props.length(); i-- != 0;)
DumpProperty(&obj->as<NativeObject>(), *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::DumpInterpreterFrame(JSContext* cx, InterpreterFrame* 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, "InterpreterFrame at %p\n", (void*) i.interpFrame());
if (i.isFunctionFrame()) {
fprintf(stderr, "callee fun: ");
RootedValue v(cx);
JSObject* fun = i.callee(cx);
v.setObject(*fun);
dumpValue(v);
} else {
fprintf(stderr, "global frame, no callee");
}
fputc('\n', stderr);
fprintf(stderr, "file %s line %" PRIuSIZE "\n",
i.script()->filename(), i.script()->lineno());
if (jsbytecode* pc = i.pc()) {
fprintf(stderr, " pc = %p\n", pc);
fprintf(stderr, " current op: %s\n", js_CodeName[*pc]);
MaybeDumpObject("staticScope", i.script()->getStaticBlockScope(pc));
}
MaybeDumpValue("this", i.thisv(cx));
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()->isDebuggerEvalFrame())
fprintf(stderr, " debugger eval");
if (i.isEvalFrame())
fprintf(stderr, " eval");
fputc('\n', stderr);
fprintf(stderr, " scopeChain: (JSObject*) %p\n", (void*) i.scopeChain(cx));
fputc('\n', stderr);
}
}
#endif /* DEBUG */
JS_FRIEND_API(void)
js::DumpBacktrace(JSContext* cx)
{
Sprinter sprinter(cx);
sprinter.init();
size_t depth = 0;
for (AllFramesIter i(cx); !i.done(); ++i, ++depth) {
const char* filename = JS_GetScriptFilename(i.script());
unsigned line = PCToLineNumber(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());
#ifdef XP_WIN32
if (IsDebuggerPresent()) {
OutputDebugStringA(sprinter.string());
}
#endif
}
/* * */
void
JSObject::addSizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf, JS::ClassInfo* info)
{
if (is<NativeObject>() && as<NativeObject>().hasDynamicSlots())
info->objectsMallocHeapSlots += mallocSizeOf(as<NativeObject>().slots_);
if (is<NativeObject>() && as<NativeObject>().hasDynamicElements()) {
js::ObjectElements* elements = as<NativeObject>().getElementsHeader();
if (!elements->isCopyOnWrite() || elements->ownerObject() == this)
info->objectsMallocHeapElementsNonAsmJS += mallocSizeOf(elements);
}
// Other things may be measured in the future if DMD indicates it is worthwhile.
if (is<JSFunction>() ||
is<PlainObject>() ||
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>()) {
info->objectsMallocHeapMisc += as<ArgumentsObject>().sizeOfMisc(mallocSizeOf);
} else if (is<RegExpStaticsObject>()) {
info->objectsMallocHeapMisc += as<RegExpStaticsObject>().sizeOfData(mallocSizeOf);
} else if (is<PropertyIteratorObject>()) {
info->objectsMallocHeapMisc += as<PropertyIteratorObject>().sizeOfMisc(mallocSizeOf);
} else if (is<ArrayBufferObject>()) {
ArrayBufferObject::addSizeOfExcludingThis(this, mallocSizeOf, info);
} else if (is<SharedArrayBufferObject>()) {
SharedArrayBufferObject::addSizeOfExcludingThis(this, mallocSizeOf, info);
} else if (is<AsmJSModuleObject>()) {
as<AsmJSModuleObject>().addSizeOfMisc(mallocSizeOf, &info->objectsNonHeapCodeAsmJS,
&info->objectsMallocHeapMisc);
#ifdef JS_HAS_CTYPES
} else {
// This must be the last case.
info->objectsMallocHeapMisc +=
js::SizeOfDataIfCDataObject(mallocSizeOf, const_cast<JSObject*>(this));
#endif
}
}
void
JSObject::markChildren(JSTracer* trc)
{
MarkObjectGroup(trc, &group_, "group");
const Class* clasp = group_->clasp();
if (clasp->trace)
clasp->trace(trc, this);
if (clasp->isNative()) {
NativeObject* nobj = &as<NativeObject>();
MarkShape(trc, &nobj->shape_, "shape");
MarkObjectSlots(trc, nobj, 0, nobj->slotSpan());
do {
if (nobj->denseElementsAreCopyOnWrite()) {
HeapPtrNativeObject& owner = nobj->getElementsHeader()->ownerObject();
if (owner != nobj) {
MarkObject(trc, &owner, "objectElementsOwner");
break;
}
}
gc::MarkArraySlots(trc,
nobj->getDenseInitializedLength(),
nobj->getDenseElementsAllowCopyOnWrite(),
"objectElements");
} while (false);
}
}