1 /* 2 * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package jdk.nashorn.internal.objects; 27 28 import static jdk.nashorn.internal.runtime.ScriptRuntime.UNDEFINED; 29 import static jdk.nashorn.internal.lookup.Lookup.MH; 30 31 import java.lang.invoke.MethodHandle; 32 import java.lang.invoke.MethodHandles; 33 import java.util.ArrayList; 34 import java.util.Arrays; 35 import jdk.nashorn.internal.runtime.AccessorProperty; 36 import jdk.nashorn.internal.runtime.Property; 37 import jdk.nashorn.internal.runtime.PropertyMap; 38 import jdk.nashorn.internal.runtime.ScriptFunction; 39 import jdk.nashorn.internal.runtime.ScriptObject; 40 import jdk.nashorn.internal.runtime.arrays.ArrayData; 41 42 /** 43 * ECMA 10.6 Arguments Object. 44 * 45 * Arguments object for strict mode functions. 46 */ 47 public final class NativeStrictArguments extends ScriptObject { 48 49 private static final MethodHandle G$LENGTH = findOwnMH("G$length", Object.class, Object.class); 50 51 private static final MethodHandle S$LENGTH = findOwnMH("S$length", void.class, Object.class, Object.class); 52 53 // property map for strict mode arguments object 54 private static final PropertyMap map$; 55 56 static { 57 final ArrayList<Property> properties = new ArrayList<>(1); 58 properties.add(AccessorProperty.create("length", Property.NOT_ENUMERABLE, G$LENGTH, S$LENGTH)); 59 PropertyMap map = PropertyMap.newMap(properties); 60 // In strict mode, the caller and callee properties should throw TypeError 61 // Need to add properties directly to map since slots are assigned speculatively by newUserAccessors. 62 final int flags = Property.NOT_ENUMERABLE | Property.NOT_CONFIGURABLE; 63 map = map.addProperty(map.newUserAccessors("caller", flags)); 64 map = map.addProperty(map.newUserAccessors("callee", flags)); 65 map$ = map.setIsShared(); 66 } 67 68 static PropertyMap getInitialMap() { 69 return map$; 70 } 71 72 private Object length; 73 private final Object[] namedArgs; 74 75 NativeStrictArguments(final Object[] values, final int numParams,final ScriptObject proto, final PropertyMap map) { 76 super(proto, map); 77 setIsArguments(); 78 79 final ScriptFunction func = Global.instance().getTypeErrorThrower(); 80 // We have to fill user accessor functions late as these are stored 81 // in this object rather than in the PropertyMap of this object. 82 setUserAccessors("caller", func, func); 83 setUserAccessors("callee", func, func); 84 85 setArray(ArrayData.allocate(values)); 86 this.length = values.length; 87 88 // extend/truncate named arg array as needed and copy values 89 this.namedArgs = new Object[numParams]; 90 if (numParams > values.length) { 91 Arrays.fill(namedArgs, UNDEFINED); 92 } 93 System.arraycopy(values, 0, namedArgs, 0, Math.min(namedArgs.length, values.length)); 94 } 95 96 @Override 97 public String getClassName() { 98 return "Arguments"; 99 } 100 101 /** 102 * getArgument is used for named argument access. 103 */ 104 @Override 105 public Object getArgument(final int key) { 106 return (key >=0 && key < namedArgs.length) ? namedArgs[key] : UNDEFINED; 107 } 108 109 /** 110 * setArgument is used for named argument set. 111 */ 112 @Override 113 public void setArgument(final int key, final Object value) { 114 if (key >= 0 && key < namedArgs.length) { 115 namedArgs[key] = value; 116 } 117 } 118 119 /** 120 * Length getter 121 * @param self self reference 122 * @return length property value 123 */ 124 public static Object G$length(final Object self) { 125 if (self instanceof NativeStrictArguments) { 126 return ((NativeStrictArguments)self).getArgumentsLength(); 127 } 128 return 0; 129 } 130 131 /** 132 * Length setter 133 * @param self self reference 134 * @param value value for length property 135 */ 136 public static void S$length(final Object self, final Object value) { 137 if (self instanceof NativeStrictArguments) { 138 ((NativeStrictArguments)self).setArgumentsLength(value); 139 } 140 } 141 142 private Object getArgumentsLength() { 143 return length; 144 } 145 146 private void setArgumentsLength(final Object length) { 147 this.length = length; 148 } 149 150 private static MethodHandle findOwnMH(final String name, final Class<?> rtype, final Class<?>... types) { 151 return MH.findStatic(MethodHandles.lookup(), NativeStrictArguments.class, name, MH.type(rtype, types)); 152 } 153 }