--- old/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/objects/NativeArguments.java 2020-04-15 18:48:34.000000000 +0530 +++ /dev/null 2020-04-15 18:48:34.000000000 +0530 @@ -1,340 +0,0 @@ -/* - * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved. - * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. - * - * This code is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License version 2 only, as - * published by the Free Software Foundation. Oracle designates this - * particular file as subject to the "Classpath" exception as provided - * by Oracle in the LICENSE file that accompanied this code. - * - * This code is distributed in the hope that it will be useful, but WITHOUT - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License - * version 2 for more details (a copy is included in the LICENSE file that - * accompanied this code). - * - * You should have received a copy of the GNU General Public License version - * 2 along with this work; if not, write to the Free Software Foundation, - * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. - * - * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA - * or visit www.oracle.com if you need additional information or have any - * questions. - */ - -package jdk.nashorn.internal.objects; - -import static jdk.nashorn.internal.lookup.Lookup.MH; -import static jdk.nashorn.internal.runtime.ECMAErrors.typeError; -import static jdk.nashorn.internal.runtime.ScriptRuntime.UNDEFINED; - -import java.lang.invoke.MethodHandle; -import java.lang.invoke.MethodHandles; -import java.util.ArrayList; -import java.util.Arrays; -import java.util.BitSet; -import jdk.nashorn.internal.runtime.AccessorProperty; -import jdk.nashorn.internal.runtime.JSType; -import jdk.nashorn.internal.runtime.Property; -import jdk.nashorn.internal.runtime.PropertyDescriptor; -import jdk.nashorn.internal.runtime.PropertyMap; -import jdk.nashorn.internal.runtime.ScriptFunction; -import jdk.nashorn.internal.runtime.ScriptObject; -import jdk.nashorn.internal.runtime.ScriptRuntime; -import jdk.nashorn.internal.runtime.arrays.ArrayData; -import jdk.nashorn.internal.runtime.arrays.ArrayIndex; - -/** - * ECMA 10.6 Arguments Object. - * - * Arguments object used for non-strict mode functions. For strict mode, we use - * a different implementation (@see NativeStrictArguments). In non-strict mode, - * named argument access and index argument access (arguments[i]) are linked. - * Modifications reflect on each other access -- till arguments indexed element - * is deleted. After delete, there is no link between named access and indexed - * access for that deleted index alone. - */ -public final class NativeArguments extends ScriptObject { - - private static final MethodHandle G$LENGTH = findOwnMH("G$length", Object.class, Object.class); - private static final MethodHandle S$LENGTH = findOwnMH("S$length", void.class, Object.class, Object.class); - private static final MethodHandle G$CALLEE = findOwnMH("G$callee", Object.class, Object.class); - private static final MethodHandle S$CALLEE = findOwnMH("S$callee", void.class, Object.class, Object.class); - - private static final PropertyMap map$; - - static { - final ArrayList properties = new ArrayList<>(2); - properties.add(AccessorProperty.create("length", Property.NOT_ENUMERABLE, G$LENGTH, S$LENGTH)); - properties.add(AccessorProperty.create("callee", Property.NOT_ENUMERABLE, G$CALLEE, S$CALLEE)); - map$ = PropertyMap.newMap(properties); - } - - static PropertyMap getInitialMap() { - return map$; - } - - private Object length; - private Object callee; - private final int numMapped; - private final int numParams; - - // These are lazily initialized when delete is invoked on a mapped arg or an unmapped argument is set. - private ArrayData unmappedArgs; - private BitSet deleted; - - NativeArguments(final Object[] arguments, final Object callee, final int numParams, final ScriptObject proto, final PropertyMap map) { - super(proto, map); - setIsArguments(); - setArray(ArrayData.allocate(arguments)); - this.length = arguments.length; - this.callee = callee; - this.numMapped = Math.min(numParams, arguments.length); - this.numParams = numParams; - } - - @Override - public String getClassName() { - return "Arguments"; - } - - /** - * getArgument is used for named argument access. - */ - @Override - public Object getArgument(final int key) { - assert key >= 0 && key < numParams : "invalid argument index"; - return isMapped(key) ? getArray().getObject(key) : getUnmappedArg(key); - } - - /** - * setArgument is used for named argument set. - */ - @Override - public void setArgument(final int key, final Object value) { - assert key >= 0 && key < numParams : "invalid argument index"; - if (isMapped(key)) { - setArray(getArray().set(key, value, false)); - } else { - setUnmappedArg(key, value); - } - } - - @Override - public boolean delete(final int key, final boolean strict) { - final int index = ArrayIndex.getArrayIndex(key); - return isMapped(index) ? deleteMapped(index, strict) : super.delete(key, strict); - } - - @Override - public boolean delete(final double key, final boolean strict) { - final int index = ArrayIndex.getArrayIndex(key); - return isMapped(index) ? deleteMapped(index, strict) : super.delete(key, strict); - } - - @Override - public boolean delete(final Object key, final boolean strict) { - final Object primitiveKey = JSType.toPrimitive(key, String.class); - final int index = ArrayIndex.getArrayIndex(primitiveKey); - return isMapped(index) ? deleteMapped(index, strict) : super.delete(primitiveKey, strict); - } - - /** - * ECMA 15.4.5.1 [[DefineOwnProperty]] ( P, Desc, Throw ) as specialized in - * ECMA 10.6 for Arguments object. - */ - @Override - public boolean defineOwnProperty(final Object key, final Object propertyDesc, final boolean reject) { - final int index = ArrayIndex.getArrayIndex(key); - if (index >= 0) { - final boolean isMapped = isMapped(index); - final Object oldValue = isMapped ? getArray().getObject(index) : null; - - if (!super.defineOwnProperty(key, propertyDesc, false)) { - if (reject) { - throw typeError("cant.redefine.property", key.toString(), ScriptRuntime.safeToString(this)); - } - return false; - } - - if (isMapped) { - // When mapped argument is redefined, if new descriptor is accessor property - // or data-non-writable property, we have to "unmap" (unlink). - final PropertyDescriptor desc = toPropertyDescriptor(Global.instance(), propertyDesc); - if (desc.type() == PropertyDescriptor.ACCESSOR) { - setDeleted(index, oldValue); - } else if (desc.has(PropertyDescriptor.WRITABLE) && !desc.isWritable()) { - // delete and set value from new descriptor if it has one, otherwise use old value - setDeleted(index, desc.has(PropertyDescriptor.VALUE) ? desc.getValue() : oldValue); - } else if (desc.has(PropertyDescriptor.VALUE)) { - setArray(getArray().set(index, desc.getValue(), false)); - } - } - - return true; - } - - return super.defineOwnProperty(key, propertyDesc, reject); - } - - // Internals below this point - - // We track deletions using a bit set (delete arguments[index]) - private boolean isDeleted(final int index) { - return deleted != null && deleted.get(index); - } - - private void setDeleted(final int index, final Object unmappedValue) { - if (deleted == null) { - deleted = new BitSet(numMapped); - } - deleted.set(index, true); - setUnmappedArg(index, unmappedValue); - } - - private boolean deleteMapped(final int index, final boolean strict) { - final Object value = getArray().getObject(index); - final boolean success = super.delete(index, strict); - if (success) { - setDeleted(index, value); - } - return success; - } - - private Object getUnmappedArg(final int key) { - assert key >= 0 && key < numParams; - return unmappedArgs == null ? UNDEFINED : unmappedArgs.getObject(key); - } - - private void setUnmappedArg(final int key, final Object value) { - assert key >= 0 && key < numParams; - if (unmappedArgs == null) { - /* - * Declared number of parameters may be more or less than the actual passed - * runtime arguments count. We need to truncate or extend with undefined values. - * - * Example: - * - * // less declared params - * (function (x) { print(arguments); })(20, 44); - * - * // more declared params - * (function (x, y) { print(arguments); })(3); - */ - final Object[] newValues = new Object[numParams]; - System.arraycopy(getArray().asObjectArray(), 0, newValues, 0, numMapped); - if (numMapped < numParams) { - Arrays.fill(newValues, numMapped, numParams, UNDEFINED); - } - this.unmappedArgs = ArrayData.allocate(newValues); - } - // Set value of argument - unmappedArgs = unmappedArgs.set(key, value, false); - } - - /** - * Are arguments[index] and corresponding named parameter linked? - * - * In non-strict mode, arguments[index] and corresponding named param are "linked" or "mapped" - * if the argument is provided by the caller. Modifications are tacked b/w each other - until - * (delete arguments[index]) is used. Once deleted, the corresponding arg is no longer 'mapped'. - * Please note that delete can happen only through the arguments array - named param can not - * be deleted. (delete is one-way). - */ - private boolean isMapped(final int index) { - // in mapped named args and not marked as "deleted" - return index >= 0 && index < numMapped && !isDeleted(index); - } - - /** - * Factory to create correct Arguments object based on strict mode. - * - * @param arguments the actual arguments array passed - * @param callee the callee function that uses arguments object - * @param numParams the number of declared (named) function parameters - * @return Arguments Object - */ - public static ScriptObject allocate(final Object[] arguments, final ScriptFunction callee, final int numParams) { - // Strict functions won't always have a callee for arguments, and will pass null instead. - final boolean isStrict = callee == null || callee.isStrict(); - final Global global = Global.instance(); - final ScriptObject proto = global.getObjectPrototype(); - if (isStrict) { - return new NativeStrictArguments(arguments, numParams, proto, NativeStrictArguments.getInitialMap()); - } - return new NativeArguments(arguments, callee, numParams, proto, NativeArguments.getInitialMap()); - } - - /** - * Length getter - * @param self self reference - * @return length property value - */ - public static Object G$length(final Object self) { - if (self instanceof NativeArguments) { - return ((NativeArguments)self).getArgumentsLength(); - } - - return 0; - } - - /** - * Length setter - * @param self self reference - * @param value value for length property - */ - public static void S$length(final Object self, final Object value) { - if (self instanceof NativeArguments) { - ((NativeArguments)self).setArgumentsLength(value); - } - } - - /** - * Callee getter - * @param self self reference - * @return value for callee property - */ - public static Object G$callee(final Object self) { - if (self instanceof NativeArguments) { - return ((NativeArguments)self).getCallee(); - } - return UNDEFINED; - } - - /** - * Callee setter - * @param self self reference - * @param value value for callee property - */ - public static void S$callee(final Object self, final Object value) { - if (self instanceof NativeArguments) { - ((NativeArguments)self).setCallee(value); - } - } - - @Override - public Object getLength() { - return length; - } - - private Object getArgumentsLength() { - return length; - } - - private void setArgumentsLength(final Object length) { - this.length = length; - } - - private Object getCallee() { - return callee; - } - - private void setCallee(final Object callee) { - this.callee = callee; - } - - private static MethodHandle findOwnMH(final String name, final Class rtype, final Class... types) { - return MH.findStatic(MethodHandles.lookup(), NativeArguments.class, name, MH.type(rtype, types)); - } -}