/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- * vim: set ts=8 sts=4 et sw=4 tw=99: * This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ /* * JS object implementation. */ #include "jsobjinlines.h" #include "mozilla/ArrayUtils.h" #include "mozilla/MathAlgorithms.h" #include "mozilla/MemoryReporting.h" #include "mozilla/TemplateLib.h" #include #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; JS_FRIEND_API(JSObject*) JS_ObjectToInnerObject(JSContext* cx, HandleObject obj) { if (!obj) { JS_ReportErrorNumber(cx, js_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()) { JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_NOT_NONNULL_OBJECT); return nullptr; } return &v.toObject(); } const char* js::InformalValueTypeName(const Value& v) { if (v.isObject()) return v.toObject().getClass()->name; if (v.isString()) return "string"; if (v.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::NewPropertyDescriptorObject(JSContext* cx, Handle desc, MutableHandleValue vp) { if (!desc.object()) { vp.setUndefined(); return true; } Rooted d(cx); d.initFromPropertyDescriptor(desc); RootedObject descObj(cx); if (!d.makeObject(cx, &descObj)) return false; vp.setObject(*descObj); return true; } void PropDesc::initFromPropertyDescriptor(Handle desc) { MOZ_ASSERT(isUndefined()); if (!desc.object()) return; isUndefined_ = false; attrs = uint8_t(desc.attributes()); MOZ_ASSERT_IF(attrs & JSPROP_READONLY, !(attrs & (JSPROP_GETTER | JSPROP_SETTER))); if (desc.hasGetterOrSetterObject()) { hasGet_ = true; get_ = desc.hasGetterObject() && desc.getterObject() ? ObjectValue(*desc.getterObject()) : UndefinedValue(); hasSet_ = true; set_ = desc.hasSetterObject() && desc.setterObject() ? ObjectValue(*desc.setterObject()) : UndefinedValue(); hasValue_ = false; value_.setUndefined(); hasWritable_ = false; } else { hasGet_ = false; get_.setUndefined(); hasSet_ = false; set_.setUndefined(); hasValue_ = !(desc.attributes() & JSPROP_IGNORE_VALUE); value_ = hasValue_ ? desc.value() : UndefinedValue(); hasWritable_ = !(desc.attributes() & JSPROP_IGNORE_READONLY); } hasEnumerable_ = !(desc.attributes() & JSPROP_IGNORE_ENUMERATE); hasConfigurable_ = !(desc.attributes() & JSPROP_IGNORE_PERMANENT); } void PropDesc::populatePropertyDescriptor(HandleObject obj, MutableHandle desc) const { if (isUndefined()) { desc.object().set(nullptr); return; } desc.value().set(hasValue() ? value() : UndefinedValue()); desc.setGetter(getter()); desc.setSetter(setter()); // Make sure we honor the "has" notions in some way. unsigned attrs = attributes(); if (!hasEnumerable()) attrs |= JSPROP_IGNORE_ENUMERATE; if (!hasWritable()) attrs |= JSPROP_IGNORE_READONLY; if (!hasConfigurable()) attrs |= JSPROP_IGNORE_PERMANENT; if (!hasValue()) attrs |= JSPROP_IGNORE_VALUE; desc.setAttributes(attrs); desc.object().set(obj); } bool PropDesc::makeObject(JSContext* cx, MutableHandleObject obj) { MOZ_ASSERT(!isUndefined()); obj.set(NewBuiltinClassInstance(cx)); if (!obj) return false; const JSAtomState& names = cx->names(); RootedValue configurableVal(cx, BooleanValue((attrs & JSPROP_PERMANENT) == 0)); RootedValue enumerableVal(cx, BooleanValue((attrs & JSPROP_ENUMERATE) != 0)); RootedValue writableVal(cx, BooleanValue((attrs & JSPROP_READONLY) == 0)); if ((hasConfigurable() && !DefineProperty(cx, obj, names.configurable, configurableVal)) || (hasEnumerable() && !DefineProperty(cx, obj, names.enumerable, enumerableVal)) || (hasGet() && !DefineProperty(cx, obj, names.get, getterValue())) || (hasSet() && !DefineProperty(cx, obj, names.set, setterValue())) || (hasValue() && !DefineProperty(cx, obj, names.value, value())) || (hasWritable() && !DefineProperty(cx, obj, names.writable, writableVal))) { return false; } return true; } bool js::GetFirstArgumentAsObject(JSContext* cx, const CallArgs& args, const char* method, MutableHandleObject objp) { if (args.length() == 0) { JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_MORE_ARGS_NEEDED, method, "0", "s"); return false; } HandleValue v = args[0]; if (!v.isObject()) { char* bytes = DecompileValueGenerator(cx, JSDVG_SEARCH_STACK, v, NullPtr()); if (!bytes) return false; JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_UNEXPECTED_TYPE, bytes, "not an object"); js_free(bytes); return false; } objp.set(&v.toObject()); return true; } static bool 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 PropDesc::initialize(JSContext* cx, const Value& origval, bool checkAccessors) { MOZ_ASSERT(isUndefined()); RootedValue v(cx, origval); /* 8.10.5 step 1 */ if (v.isPrimitive()) { JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_NOT_NONNULL_OBJECT); return false; } RootedObject desc(cx, &v.toObject()); isUndefined_ = false; /* * Start with the proper defaults. XXX shouldn't be necessary when we get * rid of PropDesc::attributes() */ attrs = JSPROP_PERMANENT | JSPROP_READONLY; bool found = false; RootedId id(cx); /* 8.10.5 step 3 */ id = NameToId(cx->names().enumerable); if (!GetPropertyIfPresent(cx, desc, id, &v, &found)) return false; if (found) { hasEnumerable_ = true; if (ToBoolean(v)) attrs |= JSPROP_ENUMERATE; } /* 8.10.5 step 4 */ id = NameToId(cx->names().configurable); if (!GetPropertyIfPresent(cx, desc, id, &v, &found)) return false; if (found) { hasConfigurable_ = true; if (ToBoolean(v)) attrs &= ~JSPROP_PERMANENT; } /* 8.10.5 step 5 */ id = NameToId(cx->names().value); if (!GetPropertyIfPresent(cx, desc, id, &v, &found)) return false; if (found) { hasValue_ = true; value_ = v; } /* 8.10.6 step 6 */ id = NameToId(cx->names().writable); if (!GetPropertyIfPresent(cx, desc, id, &v, &found)) return false; if (found) { hasWritable_ = true; if (ToBoolean(v)) attrs &= ~JSPROP_READONLY; } /* 8.10.7 step 7 */ id = NameToId(cx->names().get); if (!GetPropertyIfPresent(cx, desc, id, &v, &found)) return false; if (found) { hasGet_ = true; get_ = v; attrs |= JSPROP_GETTER | JSPROP_SHARED; attrs &= ~JSPROP_READONLY; if (checkAccessors && !checkGetter(cx)) return false; } /* 8.10.7 step 8 */ id = NameToId(cx->names().set); if (!GetPropertyIfPresent(cx, desc, id, &v, &found)) return false; if (found) { hasSet_ = true; set_ = v; attrs |= JSPROP_SETTER | JSPROP_SHARED; attrs &= ~JSPROP_READONLY; if (checkAccessors && !checkSetter(cx)) return false; } /* 8.10.7 step 9 */ if ((hasGet() || hasSet()) && (hasValue() || hasWritable())) { JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_INVALID_DESCRIPTOR); return false; } MOZ_ASSERT_IF(attrs & JSPROP_READONLY, !(attrs & (JSPROP_GETTER | JSPROP_SETTER))); return true; } void PropDesc::complete() { MOZ_ASSERT(!isUndefined()); if (isGenericDescriptor() || isDataDescriptor()) { if (!hasValue_) { hasValue_ = true; value_.setUndefined(); } if (!hasWritable_) { hasWritable_ = true; attrs |= JSPROP_READONLY; } } else { if (!hasGet_) { hasGet_ = true; get_.setUndefined(); } if (!hasSet_) { hasSet_ = true; set_.setUndefined(); } } if (!hasEnumerable_) { hasEnumerable_ = true; attrs &= ~JSPROP_ENUMERATE; } if (!hasConfigurable_) { hasConfigurable_ = true; attrs |= JSPROP_PERMANENT; } } bool js::Throw(JSContext* cx, jsid id, unsigned errorNumber) { 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, js_GetErrorMessage, nullptr, errorNumber, bytes.ptr()); return false; } bool js::Throw(JSContext* cx, JSObject* obj, unsigned errorNumber) { if (js_ErrorFormatString[errorNumber].argCount == 1) { RootedValue val(cx, ObjectValue(*obj)); js_ReportValueErrorFlags(cx, JSREPORT_ERROR, errorNumber, JSDVG_IGNORE_STACK, val, NullPtr(), nullptr, nullptr); } else { MOZ_ASSERT(js_ErrorFormatString[errorNumber].argCount == 0); JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, errorNumber); } return false; } static bool Reject(JSContext* cx, unsigned errorNumber, bool throwError, jsid id, bool* rval) { if (throwError) return Throw(cx, id, errorNumber); *rval = false; return true; } static bool Reject(JSContext* cx, JSObject* obj, unsigned errorNumber, bool throwError, bool* rval) { if (throwError) return Throw(cx, obj, errorNumber); *rval = false; return true; } static bool Reject(JSContext* cx, HandleId id, unsigned errorNumber, bool throwError, bool* rval) { if (throwError) return Throw(cx, id, errorNumber); *rval = false; return true; } /*** Standard-compliant property definition (used by Object.defineProperty) **********************/ static bool DefinePropertyOnObject(JSContext* cx, HandleNativeObject obj, HandleId id, const PropDesc& desc, bool throwError, bool* rval) { /* 8.12.9 step 1. */ RootedShape shape(cx); MOZ_ASSERT(!obj->getOps()->lookupProperty); if (!NativeLookupOwnProperty(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 Reject(cx, obj, JSMSG_OBJECT_NOT_EXTENSIBLE, throwError, rval); *rval = true; if (desc.isGenericDescriptor() || desc.isDataDescriptor()) { MOZ_ASSERT(!obj->getOps()->defineProperty); RootedValue v(cx, desc.hasValue() ? desc.value() : UndefinedValue()); return NativeDefineProperty(cx, obj, id, v, nullptr, nullptr, desc.attributes()); } MOZ_ASSERT(desc.isAccessorDescriptor()); return NativeDefineProperty(cx, obj, id, UndefinedHandleValue, desc.getter(), desc.setter(), desc.attributes()); } /* 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.hasGet()) { RootedValue getter(cx, shape->getterOrUndefined()); bool same; if (!SameValue(cx, desc.getterValue(), getter, &same)) return false; if (!same) break; } if (desc.hasSet()) { RootedValue setter(cx, shape->setterOrUndefined()); bool same; if (!SameValue(cx, desc.setterValue(), setter, &same)) return false; if (!same) break; } } else { /* * Determine the current value of the property once, if the current * value might actually need to be used or preserved later. NB: we * guard on whether the current property is a data descriptor to * avoid calling a getter; we won't need the value if it's not a * data descriptor. */ if (IsImplicitDenseOrTypedArrayElement(shape)) { v = obj->getDenseOrTypedArrayElement(JSID_TO_INT(id)); } else if (shape->isDataDescriptor()) { /* * We must rule out a non-configurable js::PropertyOp-guarded * property becoming a writable unguarded data property, since * such a property can have its value changed to one the getter * and setter preclude. * * A desc lacking writable but with value is a data descriptor * and we must reject it as if it had writable: true if current * is writable. */ if (!shape->configurable() && (!shape->hasDefaultGetter() || !shape->hasDefaultSetter()) && desc.isDataDescriptor() && (desc.hasWritable() ? desc.writable() : shape->writable())) { return Reject(cx, JSMSG_CANT_REDEFINE_PROP, throwError, id, rval); } if (!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::PropertyOp data * property is frozen at exactly the last-got value. * * Duplicate the first part of the big conjunction that * we tested above, rather than add a local bool flag. * Likewise, don't try to keep shape->writable() in a * flag we veto from true to false for non-configurable * PropertyOp-based data properties and test before the * SameValue check later on in order to re-use that "if * (!SameValue) Reject" logic. * * This function is large and complex enough that it * seems best to repeat a small bit of code and return * Reject(...) ASAP, instead of being clever. */ if (!shapeConfigurable && (!shape->hasDefaultGetter() || !shape->hasDefaultSetter())) { return Reject(cx, JSMSG_CANT_REDEFINE_PROP, throwError, id, rval); } break; } } if (desc.hasWritable() && desc.writable() != shapeWritable) break; } else { /* The only fields in desc will be handled below. */ 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. */ *rval = true; return true; } while (0); /* 8.12.9 step 7. */ if (!shapeConfigurable) { if ((desc.hasConfigurable() && desc.configurable()) || (desc.hasEnumerable() && desc.enumerable() != shape->enumerable())) { return Reject(cx, JSMSG_CANT_REDEFINE_PROP, throwError, id, rval); } } bool callDelProperty = false; if (desc.isGenericDescriptor()) { /* 8.12.9 step 8, no validation required */ } else if (desc.isDataDescriptor() != shapeDataDescriptor) { /* 8.12.9 step 9. */ if (!shapeConfigurable) return Reject(cx, JSMSG_CANT_REDEFINE_PROP, throwError, id, rval); } else if (desc.isDataDescriptor()) { /* 8.12.9 step 10. */ MOZ_ASSERT(shapeDataDescriptor); if (!shapeConfigurable && !shape->writable()) { if (desc.hasWritable() && desc.writable()) return Reject(cx, JSMSG_CANT_REDEFINE_PROP, throwError, id, rval); if (desc.hasValue()) { bool same; if (!SameValue(cx, desc.value(), v, &same)) return false; if (!same) return Reject(cx, JSMSG_CANT_REDEFINE_PROP, throwError, id, rval); } } callDelProperty = !shapeHasDefaultGetter || !shapeHasDefaultSetter; } else { /* 8.12.9 step 11. */ MOZ_ASSERT(desc.isAccessorDescriptor() && shape->isAccessorDescriptor()); if (!shape->configurable()) { if (desc.hasSet()) { RootedValue setter(cx, shape->setterOrUndefined()); bool same; if (!SameValue(cx, desc.setterValue(), setter, &same)) return false; if (!same) return Reject(cx, JSMSG_CANT_REDEFINE_PROP, throwError, id, rval); } if (desc.hasGet()) { RootedValue getter(cx, shape->getterOrUndefined()); bool same; if (!SameValue(cx, desc.getterValue(), getter, &same)) return false; if (!same) return Reject(cx, JSMSG_CANT_REDEFINE_PROP, throwError, id, rval); } } } /* 8.12.9 step 12. */ unsigned attrs; PropertyOp getter; StrictPropertyOp setter; if (desc.isGenericDescriptor()) { unsigned changed = 0; if (desc.hasConfigurable()) changed |= JSPROP_PERMANENT; if (desc.hasEnumerable()) changed |= JSPROP_ENUMERATE; attrs = (shapeAttributes & ~changed) | (desc.attributes() & changed); getter = IsImplicitDenseOrTypedArrayElement(shape) ? nullptr : shape->getter(); setter = IsImplicitDenseOrTypedArrayElement(shape) ? nullptr : shape->setter(); } else if (desc.isDataDescriptor()) { unsigned unchanged = 0; if (!desc.hasConfigurable()) unchanged |= JSPROP_PERMANENT; if (!desc.hasEnumerable()) unchanged |= JSPROP_ENUMERATE; /* Watch out for accessor -> data transformations here. */ if (!desc.hasWritable() && shapeDataDescriptor) unchanged |= JSPROP_READONLY; if (desc.hasValue()) v = desc.value(); attrs = (desc.attributes() & ~unchanged) | (shapeAttributes & unchanged); getter = 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.hasGet()) changed |= JSPROP_GETTER | JSPROP_SHARED | JSPROP_READONLY; if (desc.hasSet()) changed |= JSPROP_SETTER | JSPROP_SHARED | JSPROP_READONLY; attrs = (desc.attributes() & changed) | (shapeAttributes & ~changed); if (desc.hasGet()) { getter = desc.getter(); } else { getter = (shapeHasDefaultGetter && !shapeHasGetterValue) ? nullptr : shape->getter(); } if (desc.hasSet()) { setter = desc.setter(); } else { setter = (shapeHasDefaultSetter && !shapeHasSetterValue) ? nullptr : shape->setter(); } } *rval = true; /* * Since "data" properties implemented using native C functions may rely on * side effects during setting, we must make them aware that they have been * "assigned"; deleting the property before redefining it does the trick. * See bug 539766, where we ran into problems when we redefined * arguments.length without making the property aware that its value had * been changed (which would have happened if we had deleted it before * redefining it or we had invoked its setter to change its value). */ if (callDelProperty) { bool succeeded; if (!CallJSDeletePropertyOp(cx, obj->getClass()->delProperty, obj, id, &succeeded)) return false; } return NativeDefineProperty(cx, obj, id, v, getter, setter, attrs); } /* ES6 20130308 draft 8.4.2.1 [[DefineOwnProperty]] */ static bool DefinePropertyOnArray(JSContext* cx, Handle arr, HandleId id, const PropDesc& desc, bool throwError, bool* rval) { /* Step 2. */ if (id == NameToId(cx->names().length)) { // Canonicalize value, if necessary, before proceeding any further. It // would be better if this were always/only done by ArraySetLength. // But canonicalization may throw a RangeError (or other exception, if // the value is an object with user-defined conversion semantics) // before other attributes are checked. So as long as our internal // defineProperty hook doesn't match the ECMA one, this duplicate // checking can't be helped. RootedValue v(cx); if (desc.hasValue()) { uint32_t newLen; if (!CanonicalizeArrayLengthValue(cx, desc.value(), &newLen)) return false; v.setNumber(newLen); } else { v.setNumber(arr->length()); } if (desc.hasConfigurable() && desc.configurable()) return Reject(cx, id, JSMSG_CANT_REDEFINE_PROP, throwError, rval); if (desc.hasEnumerable() && desc.enumerable()) return Reject(cx, id, JSMSG_CANT_REDEFINE_PROP, throwError, rval); if (desc.isAccessorDescriptor()) return Reject(cx, id, JSMSG_CANT_REDEFINE_PROP, throwError, rval); unsigned attrs = arr->lookup(cx, id)->attributes(); if (!arr->lengthIsWritable()) { if (desc.hasWritable() && desc.writable()) return Reject(cx, id, JSMSG_CANT_REDEFINE_PROP, throwError, rval); } else { if (desc.hasWritable() && !desc.writable()) attrs = attrs | JSPROP_READONLY; } return ArraySetLength(cx, arr, id, attrs, v, throwError); } /* Step 3. */ uint32_t index; if (js_IdIsIndex(id, &index)) { /* Step 3b. */ uint32_t oldLen = arr->length(); /* Steps 3a, 3e. */ if (index >= oldLen && !arr->lengthIsWritable()) return Reject(cx, arr, JSMSG_CANT_APPEND_TO_ARRAY, throwError, rval); /* Steps 3f-j. */ return DefinePropertyOnObject(cx, arr, id, desc, throwError, rval); } /* Step 4. */ return DefinePropertyOnObject(cx, arr, id, desc, throwError, rval); } // ES6 draft rev31 9.4.5.3 [[DefineOwnProperty]] static bool DefinePropertyOnTypedArray(JSContext* cx, HandleObject obj, HandleId id, const PropDesc& desc, bool throwError, bool* rval) { 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)) { *rval = true; return true; } // Step vii. if (desc.isAccessorDescriptor()) return Reject(cx, id, JSMSG_CANT_REDEFINE_PROP, throwError, rval); // Step viii. if (desc.hasConfigurable() && desc.configurable()) return Reject(cx, id, JSMSG_CANT_REDEFINE_PROP, throwError, rval); // Step ix. if (desc.hasEnumerable() && !desc.enumerable()) return Reject(cx, id, JSMSG_CANT_REDEFINE_PROP, throwError, rval); // Step x. if (desc.hasWritable() && !desc.writable()) return Reject(cx, id, JSMSG_CANT_REDEFINE_PROP, throwError, rval); // Step xi. if (desc.hasValue()) { double d; if (!ToNumber(cx, desc.value(), &d)) return false; if (obj->is()) TypedArrayObject::setElement(obj->as(), index, d); else SharedTypedArrayObject::setElement(obj->as(), index, d); } // Step xii. *rval = true; return true; } // Step 4. return DefinePropertyOnObject(cx, obj.as(), id, desc, throwError, rval); } bool js::StandardDefineProperty(JSContext* cx, HandleObject obj, HandleId id, const PropDesc& desc, bool throwError, bool* rval) { if (obj->is()) { Rooted arr(cx, &obj->as()); return DefinePropertyOnArray(cx, arr, id, desc, throwError, rval); } if (IsAnyTypedArray(obj)) return DefinePropertyOnTypedArray(cx, obj, id, desc, throwError, rval); if (obj->is() && !UnboxedPlainObject::convertToNative(cx, obj)) return false; if (obj->getOps()->lookupProperty) { if (obj->is()) { Rooted pd(cx); desc.populatePropertyDescriptor(obj, &pd); pd.object().set(obj); return Proxy::defineProperty(cx, obj, id, &pd); } return Reject(cx, obj, JSMSG_OBJECT_NOT_EXTENSIBLE, throwError, rval); } return DefinePropertyOnObject(cx, obj.as(), id, desc, throwError, rval); } bool js::StandardDefineProperty(JSContext* cx, HandleObject obj, HandleId id, Handle descriptor, bool* bp) { Rooted desc(cx); desc.initFromPropertyDescriptor(descriptor); return StandardDefineProperty(cx, obj, id, desc, true, bp); } bool js::ReadPropertyDescriptors(JSContext* cx, HandleObject props, bool checkAccessors, AutoIdVector* ids, AutoPropDescVector* 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 desc(cx); RootedValue v(cx); if (!GetProperty(cx, props, props, id, &v) || !desc.initialize(cx, v, checkAccessors) || !descs->append(desc)) { return false; } } return true; } bool js::DefineProperties(JSContext* cx, HandleObject obj, HandleObject props) { AutoIdVector ids(cx); AutoPropDescVector descs(cx); if (!ReadPropertyDescriptors(cx, props, true, &ids, &descs)) return false; bool dummy; for (size_t i = 0, len = ids.length(); i < len; i++) { if (!StandardDefineProperty(cx, obj, ids[i], descs[i], true, &dummy)) 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.) bool status; if (!PreventExtensions(cx, obj, &status)) return false; if (!status) { JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_CANT_CHANGE_EXTENSIBILITY); 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().getDenseCapacity() == 0); // Steps 8-9, loosely interpreted. if (obj->isNative() && !obj->as().inDictionaryMode() && !IsAnyTypedArray(obj)) { HandleNativeObject nobj = obj.as(); // 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->getParent(), nobj->getMetadata(), 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 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 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 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 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 bool result; if (!StandardDefineProperty(cx, obj, id, desc, &result)) 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()) { if (!obj->as().maybeCopyElementsForWrite(cx)) return false; obj->as().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 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.isPermanent() || (level == IntegrityLevel::Frozen && desc.isDataDescriptor() && desc.isWritable())) { *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::FINALIZE_OBJECT8; if (clasp == &JSFunction::class_) return gc::FINALIZE_OBJECT2; return gc::FINALIZE_OBJECT4; } static inline JSObject* NewObject(ExclusiveContext* cx, HandleObjectGroup group, HandleObject parent, 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); MOZ_ASSERT_IF(parent, &parent->global() == cx->global()); JSObject* metadata = nullptr; if (!NewObjectMetadata(cx, &metadata)) return nullptr; // 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(), parent, metadata, 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()); MOZ_ASSERT(obj->getTaggedProto() == proto); return fill(entry, clasp, proto.raw(), kind, obj); } static bool NewObjectWithTaggedProtoIsCachable(ExclusiveContext* cxArg, Handle proto, NewObjectKind newKind, const Class* clasp, HandleObject parentArg) { return cxArg->isJSContext() && proto.isObject() && newKind == GenericObject && clasp->isNative() && !cxArg->asJSContext()->compartment()->hasObjectMetadataCallback() && (!parentArg || parentArg == proto.toObject()->getParent()) && !proto.toObject()->is(); } JSObject* js::NewObjectWithGivenTaggedProto(ExclusiveContext* cxArg, const Class* clasp, Handle proto, HandleObject parentArg, gc::AllocKind allocKind, NewObjectKind newKind) { if (CanBeFinalizedInBackground(allocKind, clasp)) allocKind = GetBackgroundAllocKind(allocKind); bool isCachable = NewObjectWithTaggedProtoIsCachable(cxArg, proto, newKind, clasp, parentArg); 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; /* * Default parent to the parent of the prototype, which was set from * the parent of the prototype's constructor. */ RootedObject parent(cxArg, parentArg); if (!parent && proto.isObject()) parent = proto.toObject()->getParent(); RootedObject obj(cxArg, NewObject(cxArg, group, parent, allocKind, newKind)); if (!obj) return nullptr; if (isCachable && !obj->as().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()); } 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(cx, cx->global(), id, &pobj, &shape)) return false; RootedObject ctor(cx); if (shape && pobj->isNative()) { if (shape->hasSlot()) { RootedValue v(cx, pobj->as().getSlot(shape->slot())); if (v.isObject()) ctor = &v.toObject(); } } if (ctor && ctor->is()) { JSFunction* nctor = &ctor->as(); 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, HandleObject parent, JSProtoKey protoKey, NewObjectKind newKind, const Class* clasp) { return cxArg->isJSContext() && parent->is() && protoKey != JSProto_Null && newKind == GenericObject && clasp->isNative() && !cxArg->asJSContext()->compartment()->hasObjectMetadataCallback(); } JSObject* js::NewObjectWithClassProtoCommon(ExclusiveContext* cxArg, const Class* clasp, HandleObject protoArg, HandleObject maybeParent, gc::AllocKind allocKind, NewObjectKind newKind) { if (protoArg) { return NewObjectWithGivenTaggedProto(cxArg, clasp, AsTaggedProto(protoArg), maybeParent, allocKind, newKind); } if (CanBeFinalizedInBackground(allocKind, clasp)) allocKind = GetBackgroundAllocKind(allocKind); HandleObject parent = maybeParent ? maybeParent : GlobalObject::upcast(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, parent, 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, &parent->as(), 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(cxArg, TaggedProto(proto)); RootedObjectGroup group(cxArg, ObjectGroup::defaultNewGroup(cxArg, clasp, taggedProto)); if (!group) return nullptr; JSObject* obj = NewObject(cxArg, group, parent, allocKind, newKind); if (!obj) return nullptr; if (isCachable && !obj->as().hasDynamicSlots()) { NewObjectCache& cache = cxArg->asJSContext()->runtime()->newObjectCache; NewObjectCache::EntryIndex entry = -1; cache.lookupGlobal(clasp, &parent->as(), allocKind, &entry); cache.fillGlobal(entry, clasp, &parent->as(), allocKind, &obj->as()); } return obj; } static bool NewObjectWithGroupIsCachable(JSContext* cx, HandleObjectGroup group, HandleObject parent, NewObjectKind newKind) { return group->proto().isObject() && parent == group->proto().toObject()->getParent() && newKind == GenericObject && group->clasp()->isNative() && (!group->newScript() || group->newScript()->analyzed()) && !cx->compartment()->hasObjectMetadataCallback(); } /* * 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(JSContext* cx, HandleObjectGroup group, HandleObject parent, gc::AllocKind allocKind, NewObjectKind newKind) { MOZ_ASSERT(parent); MOZ_ASSERT(allocKind <= gc::FINALIZE_OBJECT_LAST); if (CanBeFinalizedInBackground(allocKind, group->clasp())) allocKind = GetBackgroundAllocKind(allocKind); bool isCachable = NewObjectWithGroupIsCachable(cx, group, parent, newKind); if (isCachable) { NewObjectCache& cache = cx->runtime()->newObjectCache; NewObjectCache::EntryIndex entry = -1; if (cache.lookupGroup(group, allocKind, &entry)) { JSObject* obj = cache.newObjectFromHit(cx, entry, GetInitialHeap(newKind, group->clasp())); if (obj) return obj; } } JSObject* obj = NewObject(cx, group, parent, allocKind, newKind); if (!obj) return nullptr; if (isCachable && !obj->as().hasDynamicSlots()) { NewObjectCache& cache = cx->runtime()->newObjectCache; NewObjectCache::EntryIndex entry = -1; cache.lookupGroup(group, allocKind, &entry); cache.fillGroup(entry, group, allocKind, &obj->as()); } 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(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); RootedObject parent(cx, callee->getParent()); gc::AllocKind kind = NewObjectGCKind(newclasp); return NewObjectWithClassProto(cx, newclasp, proto, parent, kind); } static inline JSObject* CreateThisForFunctionWithGroup(JSContext* cx, HandleObjectGroup group, HandleObject parent, 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 finalize 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 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(cx, group, parent, allocKind, newKind); if (!res) return nullptr; // Make sure group->newScript is still there. if (newKind != SingletonObject && group->newScript()) group->newScript()->registerNewObject(res); return res; } gc::AllocKind allocKind = NewObjectGCKind(&PlainObject::class_); if (newKind == SingletonObject) { Rooted protoRoot(cx, group->proto()); RootedObject parentRoot(cx, parent); return NewObjectWithGivenTaggedProto(cx, &PlainObject::class_, protoRoot, parentRoot, allocKind, newKind); } return NewObjectWithGroup(cx, group, parent, 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())); 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()); MOZ_ASSERT(group && group->newScript()); } } RootedObject parent(cx, callee->getParent()); res = CreateThisForFunctionWithGroup(cx, group, parent, newKind); } else { RootedObject parent(cx, callee->getParent()); gc::AllocKind allocKind = NewObjectGCKind(&PlainObject::class_); res = NewObjectWithProto(cx, proto, parent, allocKind, newKind); } if (res) { JSScript* script = callee->as().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()); /* Reshape the singleton before passing it as the 'this' value. */ NativeObject::clear(cx, nobj); JSScript* calleeScript = callee->as().nonLazyScript(); TypeScript::SetThis(cx, calleeScript, TypeSet::ObjectType(nobj)); return nobj; } return obj; } /* static */ bool JSObject::nonNativeSetProperty(JSContext* cx, HandleObject obj, HandleObject receiver, HandleId id, MutableHandleValue vp, bool strict) { if (MOZ_UNLIKELY(obj->watched())) { WatchpointMap* wpmap = cx->compartment()->watchpointMap; if (wpmap && !wpmap->triggerWatchpoint(cx, obj, id, vp)) return false; } return obj->getOps()->setProperty(cx, obj, receiver, id, vp, strict); } /* static */ bool JSObject::nonNativeSetElement(JSContext* cx, HandleObject obj, HandleObject receiver, uint32_t index, MutableHandleValue vp, bool strict) { RootedId id(cx); if (!IndexToId(cx, index, &id)) return false; return nonNativeSetProperty(cx, obj, receiver, id, vp, strict); } 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 desc(cx); if (!GetOwnPropertyDescriptor(cx, obj, id, &desc)) return false; MOZ_ASSERT(desc.object()); // Silently skip JSPropertyOp-implemented accessors. if (desc.getter() && !desc.hasGetterObject()) return true; if (desc.setter() && !desc.hasSetterObject()) return true; 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; bool ignored; return StandardDefineProperty(cx, target, wrappedId, desc, &ignored); } 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 from, Handle to) { MOZ_ASSERT(from->getClass() == to->getClass()); if (from->is() && (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 proto, HandleObject parent) { if (!obj->isNative() && !obj->is()) { JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_CANT_CLONE_OBJECT); return nullptr; } RootedObject clone(cx); if (obj->isNative()) { clone = NewObjectWithGivenTaggedProto(cx, obj->getClass(), proto, parent); if (!clone) return nullptr; if (clone->is() && (obj->compartment() != clone->compartment())) { JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_CANT_CLONE_OBJECT); return nullptr; } if (obj->as().hasPrivate()) clone->as().setPrivate(obj->as().getPrivate()); } else { ProxyOptions options; options.setClass(obj->getClass()); clone = ProxyObject::New(cx, GetProxyHandler(obj), JS::NullHandleValue, proto, parent, options); if (!clone) return nullptr; if (!CopyProxyObject(cx, obj.as(), clone.as())) return nullptr; } return clone; } NativeObject* js::DeepCloneObjectLiteral(JSContext* cx, HandleNativeObject obj, NewObjectKind newKind) { /* NB: Keep this in sync with XDRObjectLiteral. */ MOZ_ASSERT_IF(obj->isSingleton(), JS::CompartmentOptionsRef(cx).getSingletonsAsTemplates()); MOZ_ASSERT(obj->is() || obj->is()); // Result of the clone function. RootedNativeObject clone(cx); // Temporary element/slot which would be stored in the cloned object. RootedValue v(cx); RootedNativeObject deepObj(cx); if (obj->is()) { clone = NewDenseUnallocatedArray(cx, obj->as().length(), NullPtr(), newKind); } else { // Object literals are tenured by default as holded by the JSScript. MOZ_ASSERT(obj->isTenured()); AllocKind kind = obj->asTenured().getAllocKind(); RootedObjectGroup group(cx, obj->getGroup(cx)); if (!group) return nullptr; RootedObject proto(cx, group->proto().toObject()); RootedObject parent(cx, obj->getParent()); clone = NewNativeObjectWithGivenProto(cx, &PlainObject::class_, proto, parent, kind, newKind); } // Allocate the same number of slots. if (!clone || !clone->ensureElements(cx, obj->getDenseCapacity())) return nullptr; // Recursive copy of dense element. uint32_t initialized = obj->getDenseInitializedLength(); for (uint32_t i = 0; i < initialized; ++i) { v = obj->getDenseElement(i); if (v.isObject()) { deepObj = &v.toObject().as(); deepObj = js::DeepCloneObjectLiteral(cx, deepObj, newKind); if (!deepObj) { JS_ReportOutOfMemory(cx); return nullptr; } v.setObject(*deepObj); } clone->setDenseInitializedLength(i + 1); clone->initDenseElement(i, v); } MOZ_ASSERT(obj->compartment() == clone->compartment()); MOZ_ASSERT(!obj->hasPrivate()); RootedShape shape(cx, obj->lastProperty()); size_t span = shape->slotSpan(); clone->setLastProperty(cx, shape); for (size_t i = 0; i < span; i++) { v = obj->getSlot(i); if (v.isObject()) { deepObj = &v.toObject().as(); deepObj = js::DeepCloneObjectLiteral(cx, deepObj, newKind); if (!deepObj) return nullptr; v.setObject(*deepObj); } clone->setSlot(i, v); } if (obj->isSingleton()) { if (!JSObject::setSingleton(cx, clone)) return nullptr; } else if (obj->is()) { ObjectGroup::fixArrayGroup(cx, &clone->as()); } else { ObjectGroup::fixPlainObjectGroup(cx, &clone->as()); } if (obj->is() && obj->denseElementsAreCopyOnWrite()) { if (!ObjectElements::MakeElementsCopyOnWrite(cx, clone)) return nullptr; } return clone; } template bool js::XDRObjectLiteral(XDRState* xdr, MutableHandleNativeObject 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() || obj->is()); isArray = obj->getClass() == &ArrayObject::class_ ? 1 : 0; } if (!xdr->codeUint32(&isArray)) return false; } if (isArray) { uint32_t length; if (mode == XDR_ENCODE) length = obj->as().length(); if (!xdr->codeUint32(&length)) return false; if (mode == XDR_DECODE) obj.set(NewDenseUnallocatedArray(cx, length, NullPtr(), js::MaybeSingletonObject)); } else { // Code the alloc kind of the object. AllocKind kind; { if (mode == XDR_ENCODE) { MOZ_ASSERT(obj->is()); MOZ_ASSERT(obj->isTenured()); kind = obj->asTenured().getAllocKind(); } if (!xdr->codeEnum32(&kind)) return false; if (mode == XDR_DECODE) { obj.set(NewBuiltinClassInstance(cx, kind, MaybeSingletonObject)); if (!obj) return false; } } } { uint32_t capacity; if (mode == XDR_ENCODE) capacity = obj->getDenseCapacity(); if (!xdr->codeUint32(&capacity)) return false; if (mode == XDR_DECODE) { if (!obj->ensureElements(cx, capacity)) { JS_ReportOutOfMemory(cx); return false; } } } uint32_t initialized; { if (mode == XDR_ENCODE) initialized = obj->getDenseInitializedLength(); if (!xdr->codeUint32(&initialized)) return false; if (mode == XDR_DECODE) { if (initialized) obj->setDenseInitializedLength(initialized); } } RootedValue tmpValue(cx); // Recursively copy dense elements. { for (unsigned i = 0; i < initialized; i++) { if (mode == XDR_ENCODE) tmpValue = obj->getDenseElement(i); if (!xdr->codeConstValue(&tmpValue)) return false; if (mode == XDR_DECODE) obj->initDenseElement(i, tmpValue); } } MOZ_ASSERT(!obj->hasPrivate()); RootedShape shape(cx, obj->lastProperty()); // Code the number of slots in the vector. unsigned nslot = 0; // Code ids of the object in order. As opposed to DeepCloneObjectLiteral we // cannot just re-use the shape of the original bytecode value and we have // to write down the shape as well as the corresponding values. Ideally we // would have a mechanism to serialize the shape too. js::AutoIdVector ids(cx); { if (mode == XDR_ENCODE && !shape->isEmptyShape()) { nslot = shape->slotSpan(); if (!ids.reserve(nslot)) return false; for (unsigned i = 0; i < nslot; i++) ids.infallibleAppend(JSID_VOID); for (Shape::Range it(shape); !it.empty(); it.popFront()) { // If we have reached the native property of the array class, we // exit as the remaining would only be reserved slots. if (!it.front().hasSlot()) { MOZ_ASSERT(isArray); break; } MOZ_ASSERT(it.front().hasDefaultGetter()); ids[it.front().slot()].set(it.front().propid()); } } if (!xdr->codeUint32(&nslot)) return false; RootedAtom atom(cx); RootedId id(cx); uint32_t idType = 0; for (unsigned i = 0; i < nslot; i++) { if (mode == XDR_ENCODE) { id = ids[i]; if (JSID_IS_INT(id)) idType = JSID_TYPE_INT; else if (JSID_IS_ATOM(id)) idType = JSID_TYPE_STRING; else MOZ_CRASH("Symbol property is not yet supported by XDR."); tmpValue = obj->getSlot(i); } if (!xdr->codeUint32(&idType)) return false; if (idType == JSID_TYPE_STRING) { if (mode == XDR_ENCODE) atom = JSID_TO_ATOM(id); if (!XDRAtom(xdr, &atom)) return false; if (mode == XDR_DECODE) id = AtomToId(atom); } else { MOZ_ASSERT(idType == JSID_TYPE_INT); uint32_t indexVal; if (mode == XDR_ENCODE) indexVal = uint32_t(JSID_TO_INT(id)); if (!xdr->codeUint32(&indexVal)) return false; if (mode == XDR_DECODE) id = INT_TO_JSID(int32_t(indexVal)); } if (!xdr->codeConstValue(&tmpValue)) return false; if (mode == XDR_DECODE) { if (!NativeDefineProperty(cx, obj, id, tmpValue, nullptr, nullptr, JSPROP_ENUMERATE)) { return false; } } } MOZ_ASSERT_IF(mode == XDR_DECODE, !obj->inDictionaryMode()); } // Fix up types, distinguishing singleton-typed objects. uint32_t isSingletonTyped; if (mode == XDR_ENCODE) isSingletonTyped = obj->isSingleton() ? 1 : 0; if (!xdr->codeUint32(&isSingletonTyped)) return false; if (mode == XDR_DECODE) { if (isSingletonTyped) { if (!JSObject::setSingleton(cx, obj)) return false; } else if (isArray) { ObjectGroup::fixArrayGroup(cx, &obj->as()); } else { ObjectGroup::fixPlainObjectGroup(cx, &obj->as()); } } { uint32_t frozen; bool extensible; if (mode == XDR_ENCODE) { if (!IsExtensible(cx, obj, &extensible)) return false; frozen = extensible ? 0 : 1; } if (!xdr->codeUint32(&frozen)) return false; if (mode == XDR_DECODE && frozen == 1) { if (!FreezeObject(cx, obj)) return false; } } if (isArray) { uint32_t copyOnWrite; if (mode == XDR_ENCODE) copyOnWrite = obj->denseElementsAreCopyOnWrite(); if (!xdr->codeUint32(©OnWrite)) return false; if (mode == XDR_DECODE && copyOnWrite) { if (!ObjectElements::MakeElementsCopyOnWrite(cx, obj)) return false; } } return true; } template bool js::XDRObjectLiteral(XDRState* xdr, MutableHandleNativeObject obj); template bool js::XDRObjectLiteral(XDRState* xdr, MutableHandleNativeObject obj); JSObject* js::CloneObjectLiteral(JSContext* cx, HandleObject parent, HandleObject srcObj) { if (srcObj->is()) { AllocKind kind = GetBackgroundAllocKind(GuessObjectGCKind(srcObj->as().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(cx, group, parent, kind, MaybeSingletonObject)); if (!res) return nullptr; RootedShape newShape(cx, ReshapeForParentAndAllocKind(cx, srcObj->lastProperty(), TaggedProto(proto), parent, kind)); if (!newShape || !res->setLastProperty(cx, newShape)) return nullptr; return res; } RootedArrayObject srcArray(cx, &srcObj->as()); MOZ_ASSERT(srcArray->denseElementsAreCopyOnWrite()); MOZ_ASSERT(srcArray->getElementsHeader()->ownerObject() == srcObj); size_t length = srcArray->as().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().zone())); 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& 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(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().inDictionaryMode()) shape_->listp = &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() == b->is()); // Don't try to swap functions with different sizes. MOZ_ASSERT_IF(a->is(), a->tenuredSizeOfThis() == b->tenuredSizeOfThis()); // Watch for oddball objects that have special organizational issues and // can't be swapped. MOZ_ASSERT(!a->is() && !b->is()); MOZ_ASSERT(!a->is() && !b->is()); MOZ_ASSERT(!a->is() && !b->is()); MOZ_ASSERT(!a->is() && !b->is()); MOZ_ASSERT(!a->is() && !b->is()); 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::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() : nullptr; NativeObject* nb = b->isNative() ? &b->as() : nullptr; // Remember the original values from the objects. Vector 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 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().fillInAfterSwap(cx, avals, apriv); if (nb) a->as().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()) { MarkChildren(zone->barrierTracer(), a); MarkChildren(zone->barrierTracer(), b); } 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 global(cx, &obj->as()); 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) { MOZ_ASSERT(!obj->getParent()); if (!obj->is()) return; obj->as().setConstructor(key, ObjectOrNullValue(cobj)); obj->as().setPrototype(key, ObjectOrNullValue(proto)); } static void ClearClassObject(JSObject* obj, JSProtoKey key) { MOZ_ASSERT(!obj->getParent()); if (!obj->is()) return; obj->as().setConstructor(key, UndefinedValue()); obj->as().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 parents the prototype object to the global and because * it uses WithProto::Given. FIXME: Undo dependencies on this parentage * [which already needs to happen for bug 638316], figure out nicer * semantics for null-protoProto, and use createBlankPrototype.) */ RootedNativeObject proto(cx, NewNativeObjectWithClassProto(cx, clasp, protoProto, obj, 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() || key == JSProto_Null) { uint32_t attrs = (clasp->flags & JSCLASS_IS_ANONYMOUS) ? JSPROP_READONLY | JSPROP_PERMANENT : 0; RootedValue value(cx, ObjectValue(*proto)); if (!DefineStandardSlot(cx, obj, key, atom, value, attrs, named)) goto bad; } ctor = proto; } else { /* * Create the constructor, not using GlobalObject::createConstructor * because the constructor currently must have |obj| as its parent. * (FIXME: remove this dependency on the exact identity of the parent, * perhaps as part of bug 638316.) */ RootedFunction fun(cx, NewFunction(cx, js::NullPtr(), constructor, nargs, JSFunction::NATIVE_CTOR, obj, atom, ctorKind)); if (!fun) goto bad; /* * Set the class object early for standard class constructors. Type * inference may need to access these, and js::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 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) { bool succeeded; RootedId id(cx, AtomToId(atom)); DeleteProperty(cx, obj, id, &succeeded); } 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& obj = as(); 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 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().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 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 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 global(cx, cx->global()); if (!MaybeResolveConstructor(cx, global, key)) return false; protop.set(&global->getPrototype(key).toObject()); return true; } bool js::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()); 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()); 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() || !(obj->as().flags() & JSFunction::NATIVE_CTOR)) return JSProto_Null; GlobalObject& global = obj->global(); for (size_t k = 0; k < JSProto_LIMIT; ++k) { JSProtoKey key = static_cast(k); if (global.getConstructor(key) == ObjectValue(*obj)) return key; } return JSProto_Null; } bool JSObject::isCallable() const { if (is()) return true; return callHook() != nullptr; } bool JSObject::isConstructor() const { if (is()) { const JSFunction& fun = as(); 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()) { const js::ProxyObject& p = as(); if (p.handler()->isCallable(const_cast(this))) return js::proxy_Call; } return nullptr; } JSNative JSObject::constructHook() const { const js::Class* clasp = getClass(); if (clasp->construct) return clasp->construct; if (is()) { const js::ProxyObject& p = as(); if (p.handler()->isConstructor(const_cast(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(cx, obj.as(), 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(cx, &scope->as(), 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(); 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()) return Proxy::hasOwn(cx, obj, id, result); if (GetOwnPropertyOp op = obj->getOps()->getOwnPropertyDescriptor) { Rooted desc(cx); if (!op(cx, obj, id, &desc)) return false; *result = !!desc.object(); return true; } RootedShape shape(cx); if (!NativeLookupOwnProperty(cx, obj.as(), 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().containsDenseElement(JSID_TO_INT(id))) { *objp = obj; MarkDenseOrTypedArrayElementFound(propp); return true; } if (IsAnyTypedArray(obj)) { uint64_t index; if (IsTypedArrayIndex(id, &index)) { if (index < AnyTypedArrayLength(obj)) { *objp = obj; MarkDenseOrTypedArrayElementFound(propp); } else { *objp = nullptr; *propp = nullptr; } return true; } } if (Shape* shape = obj->as().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 { // Search for a property on an unboxed object. Other non-native objects // are not handled here. if (!obj->is()) return false; if (obj->as().layout().lookup(id)) { *objp = obj; MarkNonNativePropertyFound(propp); return true; } } 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(), shape, vp); } bool JSObject::reportReadOnly(JSContext* cx, jsid id, unsigned report) { RootedValue val(cx, IdToValue(id)); return js_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 js_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 js_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, bool* succeeded) { /* * If |obj| has a "lazy" [[Prototype]], it is 1) a proxy 2) whose handler's * {get,set}PrototypeOf 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()); return Proxy::setPrototypeOf(cx, obj, proto, succeeded); } /* Disallow mutation of immutable [[Prototype]]s. */ if (obj->nonLazyPrototypeIsImmutable()) { *succeeded = false; return true; } /* * 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()) { JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_SETPROTOTYPEOF_FAIL, "incompatible ArrayBuffer"); return false; } /* * Disallow mutating the [[Prototype]] on Typed Objects, per the spec. */ if (obj->is()) { JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_SETPROTOTYPEOF_FAIL, "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, js_GetErrorMessage, nullptr, JSMSG_SETPROTOTYPEOF_FAIL, "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) { *succeeded = false; return true; } /* ES6 9.1.2 step 6 forbids generating cyclical prototype chains. */ RootedObject obj2(cx); for (obj2 = proto; obj2; ) { if (obj2 == obj) { *succeeded = false; return true; } if (!GetPrototype(cx, obj2, &obj2)) return false; } Rooted taggedProto(cx, TaggedProto(proto)); *succeeded = SetClassAndProto(cx, obj, obj->getClass(), taggedProto); return *succeeded; } bool js::PreventExtensions(JSContext* cx, HandleObject obj, bool* succeeded) { if (obj->is()) return js::Proxy::preventExtensions(cx, obj, succeeded); if (!obj->nonProxyIsExtensible()) { *succeeded = true; return true; } /* * Force lazy properties to be resolved by iterating over the objects' own * properties. */ 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() && !NativeObject::sparsifyDenseElements(cx, obj.as())) return false; *succeeded = true; return obj->setFlags(cx, BaseShape::NOT_EXTENSIBLE, JSObject::GENERATE_SHAPE); } bool js::GetOwnPropertyDescriptor(JSContext* cx, HandleObject obj, HandleId id, MutableHandle desc) { if (GetOwnPropertyOp op = obj->getOps()->getOwnPropertyDescriptor) return op(cx, obj, id, desc); RootedShape shape(cx); if (!NativeLookupOwnProperty(cx, obj.as(), id, &shape)) return false; if (!shape) { desc.object().set(nullptr); return true; } bool doGet = true; desc.setAttributes(GetShapeAttributes(obj, shape)); if (desc.hasGetterOrSetterObject()) { MOZ_ASSERT(desc.isShared()); doGet = false; if (desc.hasGetterObject()) desc.setGetterObject(shape->getterObject()); if (desc.hasSetterObject()) desc.setSetterObject(shape->setterObject()); } else { // This is either a straight-up data property or (rarely) a // property with a JSPropertyOp getter/setter. 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(ExclusiveContext* cx, HandleObject obj, HandleId id, HandleValue value, JSPropertyOp getter, JSStrictPropertyOp setter, unsigned attrs) { MOZ_ASSERT(getter != JS_PropertyStub); MOZ_ASSERT(setter != JS_StrictPropertyStub); MOZ_ASSERT(!(attrs & JSPROP_PROPOP_ACCESSORS)); DefinePropertyOp op = obj->getOps()->defineProperty; if (op) { if (!cx->shouldBeJSContext()) return false; return op(cx->asJSContext(), obj, id, value, getter, setter, attrs); } return NativeDefineProperty(cx, obj.as(), id, value, getter, setter, attrs); } bool js::DefineProperty(ExclusiveContext* cx, HandleObject obj, PropertyName* name, HandleValue value, JSPropertyOp getter, JSStrictPropertyOp 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, JSPropertyOp getter, JSStrictPropertyOp 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 desc) { RootedObject pobj(cx); for (pobj = obj; pobj;) { if (pobj->is()) 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())) return false; MarkTypePropertyNonData(cx, obj, id); } WatchpointMap* wpmap = cx->compartment()->watchpointMap; if (!wpmap) { wpmap = cx->runtime()->new_(); if (!wpmap || !wpmap->init()) { js_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, js_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()) 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 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(); if (ClassMethodIsNative(cx, nobj, &StringObject::class_, id, js_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(); if (ClassMethodIsNative(cx, nobj, &StringObject::class_, id, js_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(); if (ClassMethodIsNative(cx, nobj, &NumberObject::class_, id, js_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 js_ReportValueError. */ RootedString str(cx); if (hint == JSTYPE_STRING) { str = JS_InternString(cx, clasp->name); if (!str) return false; } else { str = nullptr; } RootedValue val(cx, ObjectValue(*obj)); js_ReportValueError2(cx, JSMSG_CANT_CONVERT_TO, JSDVG_SEARCH_STACK, val, str, hint == JSTYPE_VOID ? "primitive type" : 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 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) { js_ReportIsNullOrUndefined(cx, JSDVG_SEARCH_STACK, val, NullPtr()); } else { JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_CANT_CONVERT_TO, val.isNull() ? "null" : "undefined", "object"); } return nullptr; } return PrimitiveToObject(cx, val); } void js_GetObjectSlotName(JSTracer* trc, char* buf, size_t bufsize) { MOZ_ASSERT(trc->debugPrinter() == js_GetObjectSlotName); JSObject* obj = (JSObject*)trc->debugPrintArg(); uint32_t slot = uint32_t(trc->debugPrintIndex()); Shape* shape; if (obj->isNative()) { shape = obj->lastProperty(); while (shape && (!shape->hasSlot() || shape->slot() != slot)) shape = shape->previous(); } else { shape = nullptr; } if (!shape) { do { const char* slotname = nullptr; const char* pattern = nullptr; if (obj->is()) { 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()) { if (slot == ScopeObject::enclosingScopeSlot()) { slotname = "enclosing_environment"; } else if (obj->is()) { if (slot == CallObject::calleeSlot()) slotname = "callee_slot"; } else if (obj->is()) { if (slot == DeclEnvObject::lambdaSlot()) slotname = "named_lambda"; } else if (obj->is()) { 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, js_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* fun = &v.toObject().as(); if (fun->displayAtom()) { fputs("displayAtom(), 0); } else { fputs("hasScript()) { JSScript* script = fun->nonLazyScript(); fprintf(stderr, " (%s:%d)", script->filename() ? script->filename() : "", (int) script->lineno()); } fprintf(stderr, " at %p>", (void*) fun); } else if (v.isObject()) { JSObject* obj = &v.toObject(); const Class* clasp = obj->getClass(); fprintf(stderr, "<%s%s at %p>", clasp->name, (clasp == &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, ""); } 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(); } void JSObject::dump() { JSObject* obj = this; fprintf(stderr, "object %p\n", (void*) obj); const Class* clasp = obj->getClass(); fprintf(stderr, "class %p %s\n", (const void*)clasp, clasp->name); fprintf(stderr, "flags:"); if (obj->isDelegate()) fprintf(stderr, " delegate"); if (!obj->is() && !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(); if (nobj->inDictionaryMode()) fprintf(stderr, " inDictionaryMode"); if (nobj->hasShapeTable()) fprintf(stderr, " hasShapeTable"); } fprintf(stderr, "\n"); if (obj->isNative()) { NativeObject* nobj = &obj->as(); 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, ""); else dumpValue(ObjectOrNullValue(proto.toObjectOrNull())); fputc('\n', stderr); fprintf(stderr, "parent "); dumpValue(ObjectOrNullValue(obj->getParent())); fputc('\n', stderr); if (clasp->flags & JSCLASS_HAS_PRIVATE) fprintf(stderr, "private %p\n", obj->as().getPrivate()); if (!obj->isNative()) fprintf(stderr, "not native\n"); uint32_t reservedEnd = JSCLASS_RESERVED_SLOTS(clasp); uint32_t slots = obj->isNative() ? obj->as().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().getSlot(i)); fputc('\n', stderr); } if (obj->isNative()) { fprintf(stderr, "properties:\n"); Vector props; for (Shape::Range r(obj->lastProperty()); !r.empty(); r.popFront()) props.append(&r.front()); for (size_t i = props.length(); i-- != 0;) DumpProperty(&obj->as(), *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 %u\n", i.script()->filename(), (unsigned) i.script()->lineno()); if (jsbytecode* pc = i.pc()) { fprintf(stderr, " pc = %p\n", pc); fprintf(stderr, " current op: %s\n", js_CodeName[*pc]); MaybeDumpObject("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() && as().hasDynamicSlots()) info->objectsMallocHeapSlots += mallocSizeOf(as().slots_); if (is() && as().hasDynamicElements()) { js::ObjectElements* elements = as().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() || is() || is() || is() || is() || is()) { // 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()) { info->objectsMallocHeapMisc += as().sizeOfMisc(mallocSizeOf); } else if (is()) { info->objectsMallocHeapMisc += as().sizeOfData(mallocSizeOf); } else if (is()) { info->objectsMallocHeapMisc += as().sizeOfMisc(mallocSizeOf); } else if (is()) { ArrayBufferObject::addSizeOfExcludingThis(this, mallocSizeOf, info); } else if (is()) { SharedArrayBufferObject::addSizeOfExcludingThis(this, mallocSizeOf, info); } else if (is()) { as().addSizeOfMisc(mallocSizeOf, &info->objectsNonHeapCodeAsmJS, &info->objectsMallocHeapMisc); #ifdef JS_HAS_CTYPES } else { // This must be the last case. info->objectsMallocHeapMisc += js::SizeOfDataIfCDataObject(mallocSizeOf, const_cast(this)); #endif } } bool JSObject::hasIdempotentProtoChain() const { // Return false if obj (or an object on its proto chain) is non-native or // has a resolve or lookup hook. JSObject* obj = const_cast(this); while (true) { if (!obj->isNative()) return false; JSResolveOp resolve = obj->getClass()->resolve; if (resolve && resolve != js::fun_resolve && resolve != js::str_resolve) return false; if (obj->getOps()->lookupProperty) return false; obj = obj->getProto(); if (!obj) return true; } } void JSObject::markChildren(JSTracer* trc) { MarkObjectGroup(trc, &group_, "group"); MarkShape(trc, &shape_, "shape"); const Class* clasp = group_->clasp(); if (clasp->trace) clasp->trace(trc, this); if (shape_->isNative()) { NativeObject* nobj = &as(); 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); } }