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.lookup.Lookup.MH;
29 import static jdk.nashorn.internal.runtime.ScriptRuntime.UNDEFINED;
30
31 import java.lang.invoke.MethodHandle;
32 import java.util.ArrayList;
33 import jdk.nashorn.internal.runtime.GlobalFunctions;
34 import jdk.nashorn.internal.runtime.Property;
35 import jdk.nashorn.internal.runtime.PropertyMap;
36 import jdk.nashorn.internal.runtime.RecompilableScriptFunctionData;
37 import jdk.nashorn.internal.runtime.ScriptFunction;
38 import jdk.nashorn.internal.runtime.ScriptFunctionData;
39 import jdk.nashorn.internal.runtime.ScriptObject;
40 import jdk.nashorn.internal.runtime.AccessorProperty;
41
42 /**
43 * Concrete implementation of ScriptFunction. This sets correct map for the
44 * function objects -- to expose properties like "prototype", "length" etc.
45 */
46 public class ScriptFunctionImpl extends ScriptFunction {
47
48 /** Reference to constructor prototype. */
49 private Object prototype;
50
51 // property map for strict mode functions
52 private static final PropertyMap strictmodemap$;
53 // property map for bound functions
54 private static final PropertyMap boundfunctionmap$;
55 // property map for non-strict, non-bound functions.
56 private static final PropertyMap map$;
57
58 // Marker object for lazily initialized prototype object
59 private static final Object LAZY_PROTOTYPE = new Object();
60
61 private ScriptFunctionImpl(final String name, final MethodHandle invokeHandle, final MethodHandle[] specs, final Global global) {
62 super(name, invokeHandle, map$, null, specs, ScriptFunctionData.IS_BUILTIN_CONSTRUCTOR);
63 init(global);
64 }
65
66 /**
67 * Constructor called by Nasgen generated code, no membercount, use the default map.
68 * Creates builtin functions only.
69 *
70 * @param name name of function
71 * @param invokeHandle handle for invocation
72 * @param specs specialized versions of this method, if available, null otherwise
73 */
74 ScriptFunctionImpl(final String name, final MethodHandle invokeHandle, final MethodHandle[] specs) {
75 this(name, invokeHandle, specs, Global.instance());
76 }
77
78 private ScriptFunctionImpl(final String name, final MethodHandle invokeHandle, final PropertyMap map, final MethodHandle[] specs, final Global global) {
79 super(name, invokeHandle, map.addAll(map$), null, specs, ScriptFunctionData.IS_BUILTIN_CONSTRUCTOR);
80 init(global);
81 }
82
83 /**
84 * Constructor called by Nasgen generated code, no membercount, use the map passed as argument.
85 * Creates builtin functions only.
86 *
87 * @param name name of function
88 * @param invokeHandle handle for invocation
89 * @param map initial property map
90 * @param specs specialized versions of this method, if available, null otherwise
91 */
92 ScriptFunctionImpl(final String name, final MethodHandle invokeHandle, final PropertyMap map, final MethodHandle[] specs) {
93 this(name, invokeHandle, map, specs, Global.instance());
94 }
95
96 private ScriptFunctionImpl(final String name, final MethodHandle methodHandle, final ScriptObject scope, final MethodHandle[] specs, final int flags, final Global global) {
97 super(name, methodHandle, getMap(isStrict(flags)), scope, specs, flags);
98 init(global);
99 }
100
101 /**
102 * Constructor called by Global.newScriptFunction (runtime).
103 *
104 * @param name name of function
105 * @param methodHandle handle for invocation
106 * @param scope scope object
107 * @param specs specialized versions of this method, if available, null otherwise
108 * @param flags {@link ScriptFunctionData} flags
109 */
110 ScriptFunctionImpl(final String name, final MethodHandle methodHandle, final ScriptObject scope, final MethodHandle[] specs, final int flags) {
111 this(name, methodHandle, scope, specs, flags, Global.instance());
112 }
113
114 private ScriptFunctionImpl(final RecompilableScriptFunctionData data, final ScriptObject scope, final Global global) {
115 super(data, getMap(data.isStrict()), scope);
116 init(global);
117 }
118
119 /**
120 * Constructor called by (compiler) generated code for {@link ScriptObject}s.
121 *
122 * @param data static function data
123 * @param scope scope object
124 */
125 public ScriptFunctionImpl(final RecompilableScriptFunctionData data, final ScriptObject scope) {
126 this(data, scope, Global.instance());
127 }
128
129 /**
130 * Only invoked internally from {@link BoundScriptFunctionImpl} constructor.
131 * @param data the script function data for the bound function.
132 * @param global the global object
133 */
134 ScriptFunctionImpl(final ScriptFunctionData data, final Global global) {
135 super(data, boundfunctionmap$, null);
136 init(global);
137 }
138
139 static {
140 final ArrayList<Property> properties = new ArrayList<>(3);
141 properties.add(AccessorProperty.create("prototype", Property.NOT_ENUMERABLE | Property.NOT_CONFIGURABLE, G$PROTOTYPE, S$PROTOTYPE));
142 properties.add(AccessorProperty.create("length", Property.NOT_ENUMERABLE | Property.NOT_CONFIGURABLE | Property.NOT_WRITABLE, G$LENGTH, null));
143 properties.add(AccessorProperty.create("name", Property.NOT_ENUMERABLE | Property.NOT_CONFIGURABLE | Property.NOT_WRITABLE, G$NAME, null));
144 map$ = PropertyMap.newMap(properties);
145 strictmodemap$ = createStrictModeMap(map$);
146 boundfunctionmap$ = createBoundFunctionMap(strictmodemap$);
147 }
148
149 private static PropertyMap createStrictModeMap(final PropertyMap map) {
150 final int flags = Property.NOT_ENUMERABLE | Property.NOT_CONFIGURABLE;
151 PropertyMap newMap = map;
152 // Need to add properties directly to map since slots are assigned speculatively by newUserAccessors.
153 newMap = newMap.addPropertyNoHistory(map.newUserAccessors("arguments", flags));
154 newMap = newMap.addPropertyNoHistory(map.newUserAccessors("caller", flags));
155 return newMap;
156 }
157
158 private static boolean isStrict(final int flags) {
159 return (flags & ScriptFunctionData.IS_STRICT) != 0;
160 }
161
162 // Choose the map based on strict mode!
163 private static PropertyMap getMap(final boolean strict) {
164 return strict ? strictmodemap$ : map$;
165 }
166
167 private static PropertyMap createBoundFunctionMap(final PropertyMap strictModeMap) {
168 // Bound function map is same as strict function map, but additionally lacks the "prototype" property, see
169 // ECMAScript 5.1 section 15.3.4.5
170 return strictModeMap.deleteProperty(strictModeMap.findProperty("prototype"));
171 }
172
173 // Instance of this class is used as global anonymous function which
174 // serves as Function.prototype object.
175 private static class AnonymousFunction extends ScriptFunctionImpl {
176 private static final PropertyMap anonmap$ = PropertyMap.newMap();
177
178 AnonymousFunction(final Global global) {
179 super("", GlobalFunctions.ANONYMOUS, anonmap$, null);
180 }
181 }
182
183 static ScriptFunctionImpl newAnonymousFunction(final Global global) {
184 return new AnonymousFunction(global);
185 }
186
187 /**
188 * Factory method for non-constructor built-in functions
189 *
190 * @param name function name
191 * @param methodHandle handle for invocation
192 * @param specs specialized versions of function if available, null otherwise
193 * @return new ScriptFunction
194 */
195 static ScriptFunction makeFunction(final String name, final MethodHandle methodHandle, final MethodHandle[] specs) {
196 final ScriptFunctionImpl func = new ScriptFunctionImpl(name, methodHandle, null, specs, ScriptFunctionData.IS_BUILTIN);
197 func.setPrototype(UNDEFINED);
198 // Non-constructor built-in functions do not have "prototype" property
199 func.deleteOwnProperty(func.getMap().findProperty("prototype"));
200
201 return func;
202 }
203
204 /**
205 * Factory method for non-constructor built-in functions
206 *
207 * @param name function name
208 * @param methodHandle handle for invocation
209 * @return new ScriptFunction
210 */
211 static ScriptFunction makeFunction(final String name, final MethodHandle methodHandle) {
212 return makeFunction(name, methodHandle, null);
213 }
214
215 @Override
216 public ScriptFunction makeSynchronizedFunction(final Object sync) {
217 final MethodHandle mh = MH.insertArguments(ScriptFunction.INVOKE_SYNC, 0, this, sync);
218 return makeFunction(getName(), mh);
219 }
220
221 /**
222 * Same as {@link ScriptFunction#makeBoundFunction(Object, Object[])}. The only reason we override it is so that we
223 * can expose it to methods in this package.
224 * @param self the self to bind to this function. Can be null (in which case, null is bound as this).
225 * @param args additional arguments to bind to this function. Can be null or empty to not bind additional arguments.
226 * @return a function with the specified self and parameters bound.
227 */
228 @Override
229 protected ScriptFunction makeBoundFunction(Object self, Object[] args) {
230 return super.makeBoundFunction(self, args);
231 }
232
233 /**
234 * This method is used to create a bound function based on this function.
235 *
236 * @param data the {@code ScriptFunctionData} specifying the functions immutable portion.
237 * @return a function initialized from the specified data. Its parent scope will be set to null, therefore the
238 * passed in data should not expect a callee.
239 */
240 @Override
241 protected ScriptFunction makeBoundFunction(final ScriptFunctionData data) {
242 return new BoundScriptFunctionImpl(data, getTargetFunction());
243 }
244
245 // return Object.prototype - used by "allocate"
246 @Override
247 protected final ScriptObject getObjectPrototype() {
248 return Global.objectPrototype();
249 }
250
251 @Override
252 public final Object getPrototype() {
253 if (prototype == LAZY_PROTOTYPE) {
254 prototype = new PrototypeObject(this);
255 }
256 return prototype;
257 }
258
259 @Override
260 public final void setPrototype(final Object newProto) {
261 if (newProto instanceof ScriptObject && newProto != this.prototype && allocatorMap != null) {
262 // Replace our current allocator map with one that is associated with the new prototype.
263 allocatorMap = allocatorMap.changeProto((ScriptObject)newProto);
264 }
265 this.prototype = newProto;
266 }
267
268 // Internals below..
269 private void init(final Global global) {
270 this.setInitialProto(global.getFunctionPrototype());
271 this.prototype = LAZY_PROTOTYPE;
272
273 // We have to fill user accessor functions late as these are stored
274 // in this object rather than in the PropertyMap of this object.
275
276 final ScriptFunction errorThrower = global.getTypeErrorThrower();
277 if (findProperty("arguments", true) != null) {
278 setUserAccessors("arguments", errorThrower, errorThrower);
279 }
280
281 if (findProperty("caller", true) != null) {
282 setUserAccessors("caller", errorThrower, errorThrower);
283 }
284 }
285 }