1 /*
2 * Copyright (c) 2010, 2016, 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.runtime.linker;
27
28 import static jdk.nashorn.internal.runtime.JSType.isString;
29
30 import java.lang.invoke.MethodHandle;
31 import java.lang.invoke.MethodHandles;
32 import java.lang.invoke.MethodType;
33 import java.util.Map;
34 import javax.script.Bindings;
35 import jdk.dynalink.CallSiteDescriptor;
36 import jdk.dynalink.Operation;
37 import jdk.dynalink.StandardOperation;
38 import jdk.dynalink.linker.GuardedInvocation;
39 import jdk.dynalink.linker.LinkRequest;
40 import jdk.dynalink.linker.LinkerServices;
41 import jdk.dynalink.linker.TypeBasedGuardingDynamicLinker;
42 import jdk.nashorn.api.scripting.JSObject;
43 import jdk.nashorn.api.scripting.ScriptObjectMirror;
44 import jdk.nashorn.internal.lookup.MethodHandleFactory;
45 import jdk.nashorn.internal.lookup.MethodHandleFunctionality;
46 import jdk.nashorn.internal.runtime.Context;
47 import jdk.nashorn.internal.runtime.JSType;
48 import jdk.nashorn.internal.runtime.ScriptRuntime;
49 import jdk.nashorn.internal.objects.Global;
50
51 /**
52 * A Dynalink linker to handle web browser built-in JS (DOM etc.) objects as well
53 * as ScriptObjects from other Nashorn contexts.
54 */
55 final class JSObjectLinker implements TypeBasedGuardingDynamicLinker {
56 private final NashornBeansLinker nashornBeansLinker;
57
58 JSObjectLinker(final NashornBeansLinker nashornBeansLinker) {
59 this.nashornBeansLinker = nashornBeansLinker;
60 }
61
62 @Override
63 public boolean canLinkType(final Class<?> type) {
64 return canLinkTypeStatic(type);
65 }
66
67 static boolean canLinkTypeStatic(final Class<?> type) {
68 // can link JSObject also handles Map, Bindings to make
69 // sure those are not JSObjects.
70 return Map.class.isAssignableFrom(type) ||
71 Bindings.class.isAssignableFrom(type) ||
72 JSObject.class.isAssignableFrom(type);
73 }
74
75 @Override
76 public GuardedInvocation getGuardedInvocation(final LinkRequest request, final LinkerServices linkerServices) throws Exception {
77 final Object self = request.getReceiver();
78 final CallSiteDescriptor desc = request.getCallSiteDescriptor();
79 if (self == null || !canLinkTypeStatic(self.getClass())) {
80 return null;
81 }
82
83 GuardedInvocation inv;
84 if (self instanceof JSObject) {
85 inv = lookup(desc, request, linkerServices);
86 inv = inv.replaceMethods(linkerServices.filterInternalObjects(inv.getInvocation()), inv.getGuard());
87 } else if (self instanceof Map || self instanceof Bindings) {
88 // guard to make sure the Map or Bindings does not turn into JSObject later!
89 final GuardedInvocation beanInv = nashornBeansLinker.getGuardedInvocation(request, linkerServices);
90 inv = new GuardedInvocation(beanInv.getInvocation(),
91 NashornGuards.combineGuards(beanInv.getGuard(), NashornGuards.getNotJSObjectGuard()));
92 } else {
93 throw new AssertionError("got instanceof: " + self.getClass()); // Should never reach here.
94 }
95
96 return Bootstrap.asTypeSafeReturn(inv, linkerServices, desc);
97 }
98
99 private GuardedInvocation lookup(final CallSiteDescriptor desc, final LinkRequest request, final LinkerServices linkerServices) throws Exception {
100 final Operation op = NashornCallSiteDescriptor.getBaseOperation(desc);
101 if (op instanceof StandardOperation) {
102 final String name = NashornCallSiteDescriptor.getOperand(desc);
103 switch ((StandardOperation)op) {
104 case GET:
105 if (NashornCallSiteDescriptor.hasStandardNamespace(desc)) {
106 if (name != null) {
107 return findGetMethod(name);
108 }
109 // For indexed get, we want get GuardedInvocation beans linker and pass it.
110 // JSObjectLinker.get uses this fallback getter for explicit signature method access.
111 return findGetIndexMethod(nashornBeansLinker.getGuardedInvocation(request, linkerServices));
112 }
113 break;
114 case SET:
115 if (NashornCallSiteDescriptor.hasStandardNamespace(desc)) {
116 return name != null ? findSetMethod(name) : findSetIndexMethod();
117 }
118 break;
119 case CALL:
120 return findCallMethod(desc);
121 case NEW:
122 return findNewMethod(desc);
123 default:
124 }
125 }
126 return null;
127 }
128
129 private static GuardedInvocation findGetMethod(final String name) {
130 final MethodHandle getter = MH.insertArguments(JSOBJECT_GETMEMBER, 1, name);
131 return new GuardedInvocation(getter, IS_JSOBJECT_GUARD);
132 }
133
134 private static GuardedInvocation findGetIndexMethod(final GuardedInvocation inv) {
135 final MethodHandle getter = MH.insertArguments(JSOBJECTLINKER_GET, 0, inv.getInvocation());
136 return inv.replaceMethods(getter, inv.getGuard());
137 }
138
139 private static GuardedInvocation findSetMethod(final String name) {
140 final MethodHandle getter = MH.insertArguments(JSOBJECT_SETMEMBER, 1, name);
141 return new GuardedInvocation(getter, IS_JSOBJECT_GUARD);
142 }
143
144 private static GuardedInvocation findSetIndexMethod() {
145 return new GuardedInvocation(JSOBJECTLINKER_PUT, IS_JSOBJECT_GUARD);
146 }
147
148 private static GuardedInvocation findCallMethod(final CallSiteDescriptor desc) {
149 MethodHandle mh = NashornCallSiteDescriptor.isScope(desc)? JSOBJECT_SCOPE_CALL : JSOBJECT_CALL;
150 if (NashornCallSiteDescriptor.isApplyToCall(desc)) {
151 mh = MH.insertArguments(JSOBJECT_CALL_TO_APPLY, 0, mh);
152 }
153 final MethodType type = desc.getMethodType();
154 mh = type.parameterType(type.parameterCount() - 1) == Object[].class ?
155 mh :
156 MH.asCollector(mh, Object[].class, type.parameterCount() - 2);
157 return new GuardedInvocation(mh, IS_JSOBJECT_GUARD);
158 }
159
160 private static GuardedInvocation findNewMethod(final CallSiteDescriptor desc) {
161 final MethodHandle func = MH.asCollector(JSOBJECT_NEW, Object[].class, desc.getMethodType().parameterCount() - 1);
162 return new GuardedInvocation(func, IS_JSOBJECT_GUARD);
163 }
164
165 @SuppressWarnings("unused")
166 private static boolean isJSObject(final Object self) {
167 return self instanceof JSObject;
168 }
169
170 @SuppressWarnings("unused")
171 private static Object get(final MethodHandle fallback, final Object jsobj, final Object key)
172 throws Throwable {
173 if (key instanceof Integer) {
174 return ((JSObject)jsobj).getSlot((Integer)key);
175 } else if (key instanceof Number) {
176 final int index = getIndex((Number)key);
177 if (index > -1) {
178 return ((JSObject)jsobj).getSlot(index);
179 } else {
180 return ((JSObject)jsobj).getMember(JSType.toString(key));
181 }
182 } else if (isString(key)) {
183 final String name = key.toString();
184 // get with method name and signature. delegate it to beans linker!
185 if (name.indexOf('(') != -1) {
186 return fallback.invokeExact(jsobj, (Object) name);
187 }
188 return ((JSObject)jsobj).getMember(name);
189 }
190 return null;
191 }
192
193 @SuppressWarnings("unused")
194 private static void put(final Object jsobj, final Object key, final Object value) {
195 if (key instanceof Integer) {
196 ((JSObject)jsobj).setSlot((Integer)key, value);
197 } else if (key instanceof Number) {
198 final int index = getIndex((Number)key);
199 if (index > -1) {
200 ((JSObject)jsobj).setSlot(index, value);
201 } else {
202 ((JSObject)jsobj).setMember(JSType.toString(key), value);
203 }
204 } else if (isString(key)) {
205 ((JSObject)jsobj).setMember(key.toString(), value);
206 }
207 }
208
209 private static int getIndex(final Number n) {
210 final double value = n.doubleValue();
211 return JSType.isRepresentableAsInt(value) ? (int)value : -1;
212 }
213
214 @SuppressWarnings("unused")
215 private static Object callToApply(final MethodHandle mh, final JSObject obj, final Object thiz, final Object... args) {
216 assert args.length >= 2;
217 final Object receiver = args[0];
218 final Object[] arguments = new Object[args.length - 1];
219 System.arraycopy(args, 1, arguments, 0, arguments.length);
220 try {
221 return mh.invokeExact(obj, thiz, new Object[] { receiver, arguments });
222 } catch (final RuntimeException | Error e) {
223 throw e;
224 } catch (final Throwable e) {
225 throw new RuntimeException(e);
226 }
227 }
228
229 // This is used when a JSObject is called as scope call to do undefined -> Global this translation.
230 @SuppressWarnings("unused")
231 private static Object jsObjectScopeCall(final JSObject jsObj, final Object thiz, final Object[] args) {
232 final Object modifiedThiz;
233 if (thiz == ScriptRuntime.UNDEFINED && !jsObj.isStrictFunction()) {
234 final Global global = Context.getGlobal();
235 modifiedThiz = ScriptObjectMirror.wrap(global, global);
236 } else {
237 modifiedThiz = thiz;
238 }
239 return jsObj.call(modifiedThiz, args);
240 }
241
242 private static final MethodHandleFunctionality MH = MethodHandleFactory.getFunctionality();
243
244 // method handles of the current class
245 private static final MethodHandle IS_JSOBJECT_GUARD = findOwnMH_S("isJSObject", boolean.class, Object.class);
246 private static final MethodHandle JSOBJECTLINKER_GET = findOwnMH_S("get", Object.class, MethodHandle.class, Object.class, Object.class);
247 private static final MethodHandle JSOBJECTLINKER_PUT = findOwnMH_S("put", Void.TYPE, Object.class, Object.class, Object.class);
248
249 // method handles of JSObject class
250 private static final MethodHandle JSOBJECT_GETMEMBER = findJSObjectMH_V("getMember", Object.class, String.class);
251 private static final MethodHandle JSOBJECT_SETMEMBER = findJSObjectMH_V("setMember", Void.TYPE, String.class, Object.class);
252 private static final MethodHandle JSOBJECT_CALL = findJSObjectMH_V("call", Object.class, Object.class, Object[].class);
253 private static final MethodHandle JSOBJECT_SCOPE_CALL = findOwnMH_S("jsObjectScopeCall", Object.class, JSObject.class, Object.class, Object[].class);
254 private static final MethodHandle JSOBJECT_CALL_TO_APPLY = findOwnMH_S("callToApply", Object.class, MethodHandle.class, JSObject.class, Object.class, Object[].class);
255 private static final MethodHandle JSOBJECT_NEW = findJSObjectMH_V("newObject", Object.class, Object[].class);
256
257 private static MethodHandle findJSObjectMH_V(final String name, final Class<?> rtype, final Class<?>... types) {
258 return MH.findVirtual(MethodHandles.lookup(), JSObject.class, name, MH.type(rtype, types));
259 }
260
261 private static MethodHandle findOwnMH_S(final String name, final Class<?> rtype, final Class<?>... types) {
262 return MH.findStatic(MethodHandles.lookup(), JSObjectLinker.class, name, MH.type(rtype, types));
263 }
264 }