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$;
57
58 static PropertyMap getInitialMap() {
59 return map$;
60 }
61
62 static PropertyMap getInitialAnonymousMap() {
63 return AnonymousFunction.getInitialMap();
64 }
65
66 static PropertyMap getInitialStrictMap() {
67 return strictmodemap$;
68 }
69
70 static PropertyMap getInitialBoundMap() {
71 return boundfunctionmap$;
72 }
73
74 // Marker object for lazily initialized prototype object
75 private static final Object LAZY_PROTOTYPE = new Object();
76
77 private ScriptFunctionImpl(final String name, final MethodHandle invokeHandle, final MethodHandle[] specs, final Global global) {
78 super(name, invokeHandle, getInitialMap(), null, specs, ScriptFunctionData.IS_BUILTIN_CONSTRUCTOR);
79 init(global);
80 }
81
82 /**
83 * Constructor called by Nasgen generated code, no membercount, use the default map.
84 * Creates builtin functions only.
85 *
86 * @param name name of function
87 * @param invokeHandle handle for invocation
88 * @param specs specialized versions of this method, if available, null otherwise
89 */
90 ScriptFunctionImpl(final String name, final MethodHandle invokeHandle, final MethodHandle[] specs) {
91 this(name, invokeHandle, specs, Global.instance());
92 }
93
94 private ScriptFunctionImpl(final String name, final MethodHandle invokeHandle, final PropertyMap map, final MethodHandle[] specs, final Global global) {
95 super(name, invokeHandle, map.addAll(getInitialMap()), null, specs, ScriptFunctionData.IS_BUILTIN_CONSTRUCTOR);
96 init(global);
97 }
98
99 /**
100 * Constructor called by Nasgen generated code, no membercount, use the map passed as argument.
101 * Creates builtin functions only.
102 *
103 * @param name name of function
104 * @param invokeHandle handle for invocation
105 * @param map initial property map
106 * @param specs specialized versions of this method, if available, null otherwise
107 */
108 ScriptFunctionImpl(final String name, final MethodHandle invokeHandle, final PropertyMap map, final MethodHandle[] specs) {
109 this(name, invokeHandle, map, specs, Global.instance());
110 }
111
112 private ScriptFunctionImpl(final String name, final MethodHandle methodHandle, final ScriptObject scope, final MethodHandle[] specs, final int flags, final Global global) {
113 super(name, methodHandle, getMap(global, isStrict(flags)), scope, specs, flags);
114 init(global);
115 }
116
117 /**
118 * Constructor called by Global.newScriptFunction (runtime).
119 *
120 * @param name name of function
121 * @param methodHandle handle for invocation
122 * @param scope scope object
123 * @param specs specialized versions of this method, if available, null otherwise
124 * @param flags {@link ScriptFunctionData} flags
125 */
126 ScriptFunctionImpl(final String name, final MethodHandle methodHandle, final ScriptObject scope, final MethodHandle[] specs, final int flags) {
127 this(name, methodHandle, scope, specs, flags, Global.instance());
128 }
129
130 private ScriptFunctionImpl(final RecompilableScriptFunctionData data, final ScriptObject scope, final Global global) {
131 super(data, getMap(global, data.isStrict()), scope);
132 init(global);
133 }
134
135 /**
136 * Constructor called by (compiler) generated code for {@link ScriptObject}s.
137 *
138 * @param data static function data
139 * @param scope scope object
140 */
141 public ScriptFunctionImpl(final RecompilableScriptFunctionData data, final ScriptObject scope) {
142 this(data, scope, Global.instance());
143 }
144
145 /**
146 * Only invoked internally from {@link BoundScriptFunctionImpl} constructor.
147 * @param data the script function data for the bound function.
148 * @param global the global object
149 */
150 ScriptFunctionImpl(final ScriptFunctionData data, final Global global) {
151 super(data, getInitialBoundMap(), null);
152 init(global);
153 }
154
155 static {
156 final ArrayList<Property> properties = new ArrayList<>(3);
157 properties.add(AccessorProperty.create("prototype", Property.NOT_ENUMERABLE | Property.NOT_CONFIGURABLE, G$PROTOTYPE, S$PROTOTYPE));
158 properties.add(AccessorProperty.create("length", Property.NOT_ENUMERABLE | Property.NOT_CONFIGURABLE | Property.NOT_WRITABLE, G$LENGTH, null));
159 properties.add(AccessorProperty.create("name", Property.NOT_ENUMERABLE | Property.NOT_CONFIGURABLE | Property.NOT_WRITABLE, G$NAME, null));
160 map$ = PropertyMap.newMap(properties);
161 strictmodemap$ = createStrictModeMap(map$);
162 boundfunctionmap$ = createBoundFunctionMap(strictmodemap$);
163 }
164
165 private static PropertyMap createStrictModeMap(final PropertyMap map) {
166 final int flags = Property.NOT_ENUMERABLE | Property.NOT_CONFIGURABLE;
167 PropertyMap newMap = map;
168 // Need to add properties directly to map since slots are assigned speculatively by newUserAccessors.
169 newMap = newMap.addPropertyNoHistory(map.newUserAccessors("arguments", flags));
170 newMap = newMap.addPropertyNoHistory(map.newUserAccessors("caller", flags));
171 return newMap;
172 }
173
174 private static boolean isStrict(final int flags) {
175 return (flags & ScriptFunctionData.IS_STRICT) != 0;
176 }
177
178 // Choose the map based on strict mode!
179 private static PropertyMap getMap(final Global global, final boolean strict) {
180 return strict ? getInitialStrictMap() : getInitialMap();
181 }
182
183 private static PropertyMap createBoundFunctionMap(final PropertyMap strictModeMap) {
184 // Bound function map is same as strict function map, but additionally lacks the "prototype" property, see
185 // ECMAScript 5.1 section 15.3.4.5
186 return strictModeMap.deleteProperty(strictModeMap.findProperty("prototype"));
187 }
188
189 // Instance of this class is used as global anonymous function which
190 // serves as Function.prototype object.
191 private static class AnonymousFunction extends ScriptFunctionImpl {
192 private static final PropertyMap anonmap$ = PropertyMap.newMap();
193
194 static PropertyMap getInitialMap() {
195 return anonmap$;
196 }
197
198 AnonymousFunction(final Global global) {
199 super("", GlobalFunctions.ANONYMOUS, getInitialAnonymousMap(), null);
200 }
201 }
202
203 static ScriptFunctionImpl newAnonymousFunction(final Global global) {
204 return new AnonymousFunction(global);
205 }
206
207 /**
208 * Factory method for non-constructor built-in functions
209 *
210 * @param name function name
211 * @param methodHandle handle for invocation
212 * @param specs specialized versions of function if available, null otherwise
213 * @return new ScriptFunction
214 */
215 static ScriptFunction makeFunction(final String name, final MethodHandle methodHandle, final MethodHandle[] specs) {
216 final ScriptFunctionImpl func = new ScriptFunctionImpl(name, methodHandle, null, specs, ScriptFunctionData.IS_BUILTIN);
217 func.setPrototype(UNDEFINED);
218 // Non-constructor built-in functions do not have "prototype" property
219 func.deleteOwnProperty(func.getMap().findProperty("prototype"));
220
221 return func;
222 }
223
224 /**
225 * Factory method for non-constructor built-in functions
226 *
227 * @param name function name
228 * @param methodHandle handle for invocation
229 * @return new ScriptFunction
230 */
231 static ScriptFunction makeFunction(final String name, final MethodHandle methodHandle) {
232 return makeFunction(name, methodHandle, null);
233 }
234
235 @Override
236 public ScriptFunction makeSynchronizedFunction(final Object sync) {
237 final MethodHandle mh = MH.insertArguments(ScriptFunction.INVOKE_SYNC, 0, this, sync);
238 return makeFunction(getName(), mh);
239 }
240
241 /**
242 * Same as {@link ScriptFunction#makeBoundFunction(Object, Object[])}. The only reason we override it is so that we
243 * can expose it to methods in this package.
244 * @param self the self to bind to this function. Can be null (in which case, null is bound as this).
245 * @param args additional arguments to bind to this function. Can be null or empty to not bind additional arguments.
246 * @return a function with the specified self and parameters bound.
247 */
248 @Override
249 protected ScriptFunction makeBoundFunction(Object self, Object[] args) {
250 return super.makeBoundFunction(self, args);
251 }
252
253 /**
254 * This method is used to create a bound function based on this function.
255 *
256 * @param data the {@code ScriptFunctionData} specifying the functions immutable portion.
257 * @return a function initialized from the specified data. Its parent scope will be set to null, therefore the
258 * passed in data should not expect a callee.
259 */
260 @Override
261 protected ScriptFunction makeBoundFunction(final ScriptFunctionData data) {
262 return new BoundScriptFunctionImpl(data, getTargetFunction());
263 }
264
265 // return Object.prototype - used by "allocate"
266 @Override
267 protected final ScriptObject getObjectPrototype() {
268 return Global.objectPrototype();
269 }
270
271 @Override
272 public final Object getPrototype() {
273 if (prototype == LAZY_PROTOTYPE) {
274 prototype = new PrototypeObject(this);
275 }
276 return prototype;
277 }
278
279 @Override
280 public final void setPrototype(final Object newProto) {
281 if (newProto instanceof ScriptObject && newProto != this.prototype && allocatorMap != null) {
282 // Replace our current allocator map with one that is associated with the new prototype.
283 allocatorMap = allocatorMap.changeProto((ScriptObject)newProto);
284 }
285 this.prototype = newProto;
286 }
287
288 // Internals below..
289 private void init(final Global global) {
290 this.setInitialProto(global.getFunctionPrototype());
291 this.prototype = LAZY_PROTOTYPE;
292
293 // We have to fill user accessor functions late as these are stored
294 // in this object rather than in the PropertyMap of this object.
295
296 final ScriptFunction errorThrower = global.getTypeErrorThrower();
297 if (findProperty("arguments", true) != null) {
298 setUserAccessors("arguments", errorThrower, errorThrower);
299 }
300
301 if (findProperty("caller", true) != null) {
302 setUserAccessors("caller", errorThrower, errorThrower);
303 }
304 }
305 }