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$LENGTH));
59 PropertyMap map = PropertyMap.newMap(properties);
60 // In strict mode, the caller and callee properties should throw TypeError
61 // Need to add properties directly to map since slots are assigned speculatively by newUserAccessors.
62 final int flags = Property.NOT_ENUMERABLE | Property.NOT_CONFIGURABLE;
63 map = map.addPropertyNoHistory(map.newUserAccessors("caller", flags));
64 map = map.addPropertyNoHistory(map.newUserAccessors("callee", flags));
65 map$ = map;
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 }