InternalNative.cpp revision 062bf509a77fce9dfcb7e7b2e401cf2a124d83d5 
1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17/*
18 * Internal-native initialization and some common utility functions.
19 */
20#include "Dalvik.h"
21#include "native/InternalNativePriv.h"
22
23/*
24 * Set of classes for which we provide methods.
25 *
26 * The last field, classNameHash, is filled in at startup.
27 */
28static DalvikNativeClass gDvmNativeMethodSet[] = {
29    { "Ljava/lang/Object;",               dvm_java_lang_Object, 0 },
30    { "Ljava/lang/Class;",                dvm_java_lang_Class, 0 },
31    { "Ljava/lang/Double;",               dvm_java_lang_Double, 0 },
32    { "Ljava/lang/Float;",                dvm_java_lang_Float, 0 },
33    { "Ljava/lang/Math;",                 dvm_java_lang_Math, 0 },
34    { "Ljava/lang/Runtime;",              dvm_java_lang_Runtime, 0 },
35    { "Ljava/lang/String;",               dvm_java_lang_String, 0 },
36    { "Ljava/lang/System;",               dvm_java_lang_System, 0 },
37    { "Ljava/lang/Throwable;",            dvm_java_lang_Throwable, 0 },
38    { "Ljava/lang/VMClassLoader;",        dvm_java_lang_VMClassLoader, 0 },
39    { "Ljava/lang/VMThread;",             dvm_java_lang_VMThread, 0 },
40    { "Ljava/lang/reflect/AccessibleObject;",
41            dvm_java_lang_reflect_AccessibleObject, 0 },
42    { "Ljava/lang/reflect/Array;",        dvm_java_lang_reflect_Array, 0 },
43    { "Ljava/lang/reflect/Constructor;",
44            dvm_java_lang_reflect_Constructor, 0 },
45    { "Ljava/lang/reflect/Field;",        dvm_java_lang_reflect_Field, 0 },
46    { "Ljava/lang/reflect/Method;",       dvm_java_lang_reflect_Method, 0 },
47    { "Ljava/lang/reflect/Proxy;",        dvm_java_lang_reflect_Proxy, 0 },
48    { "Ljava/util/concurrent/atomic/AtomicLong;",
49            dvm_java_util_concurrent_atomic_AtomicLong, 0 },
50    { "Ldalvik/bytecode/OpcodeInfo;",     dvm_dalvik_bytecode_OpcodeInfo, 0 },
51    { "Ldalvik/system/VMDebug;",          dvm_dalvik_system_VMDebug, 0 },
52    { "Ldalvik/system/DexFile;",          dvm_dalvik_system_DexFile, 0 },
53    { "Ldalvik/system/VMRuntime;",        dvm_dalvik_system_VMRuntime, 0 },
54    { "Ldalvik/system/Zygote;",           dvm_dalvik_system_Zygote, 0 },
55    { "Ldalvik/system/VMStack;",          dvm_dalvik_system_VMStack, 0 },
56    { "Lorg/apache/harmony/dalvik/ddmc/DdmServer;",
57            dvm_org_apache_harmony_dalvik_ddmc_DdmServer, 0 },
58    { "Lorg/apache/harmony/dalvik/ddmc/DdmVmInternal;",
59            dvm_org_apache_harmony_dalvik_ddmc_DdmVmInternal, 0 },
60    { "Lorg/apache/harmony/dalvik/NativeTestTarget;",
61            dvm_org_apache_harmony_dalvik_NativeTestTarget, 0 },
62    { "Lsun/misc/Unsafe;",                dvm_sun_misc_Unsafe, 0 },
63    { NULL, NULL, 0 },
64};
65
66
67/*
68 * Set up hash values on the class names.
69 */
70bool dvmInternalNativeStartup()
71{
72    DalvikNativeClass* classPtr = gDvmNativeMethodSet;
73
74    while (classPtr->classDescriptor != NULL) {
75        classPtr->classDescriptorHash =
76            dvmComputeUtf8Hash(classPtr->classDescriptor);
77        classPtr++;
78    }
79
80    gDvm.userDexFiles = dvmHashTableCreate(2, dvmFreeDexOrJar);
81    if (gDvm.userDexFiles == NULL)
82        return false;
83
84    return true;
85}
86
87/*
88 * Clean up.
89 */
90void dvmInternalNativeShutdown()
91{
92    dvmHashTableFree(gDvm.userDexFiles);
93}
94
95/*
96 * Search the internal native set for a match.
97 */
98DalvikNativeFunc dvmLookupInternalNativeMethod(const Method* method)
99{
100    const char* classDescriptor = method->clazz->descriptor;
101    const DalvikNativeClass* pClass;
102    u4 hash;
103
104    hash = dvmComputeUtf8Hash(classDescriptor);
105    pClass = gDvmNativeMethodSet;
106    while (true) {
107        if (pClass->classDescriptor == NULL)
108            break;
109        if (pClass->classDescriptorHash == hash &&
110            strcmp(pClass->classDescriptor, classDescriptor) == 0)
111        {
112            const DalvikNativeMethod* pMeth = pClass->methodInfo;
113            while (true) {
114                if (pMeth->name == NULL)
115                    break;
116
117                if (dvmCompareNameDescriptorAndMethod(pMeth->name,
118                    pMeth->signature, method) == 0)
119                {
120                    /* match */
121                    //ALOGV("+++  match on %s.%s %s at %p",
122                    //    className, methodName, methodSignature, pMeth->fnPtr);
123                    return pMeth->fnPtr;
124                }
125
126                pMeth++;
127            }
128        }
129
130        pClass++;
131    }
132
133    return NULL;
134}
135
136
137/*
138 * Magic "internal native" code stub, inserted into abstract method
139 * definitions when a class is first loaded.  This throws the expected
140 * exception so we don't have to explicitly check for it in the interpreter.
141 */
142void dvmAbstractMethodStub(const u4* args, JValue* pResult)
143{
144    ALOGD("--- called into dvmAbstractMethodStub");
145    dvmThrowAbstractMethodError("abstract method not implemented");
146}
147
148
149/*
150 * Verify that "obj" is non-null and is an instance of "clazz".
151 * Used to implement reflection on fields and methods.
152 *
153 * Returns "false" and throws an exception if not.
154 */
155bool dvmVerifyObjectInClass(Object* obj, ClassObject* clazz) {
156    ClassObject* exceptionClass = NULL;
157    if (obj == NULL) {
158        exceptionClass = gDvm.exNullPointerException;
159    } else if (!dvmInstanceof(obj->clazz, clazz)) {
160        exceptionClass = gDvm.exIllegalArgumentException;
161    }
162
163    if (exceptionClass == NULL) {
164        return true;
165    }
166
167    std::string expectedClassName(dvmHumanReadableDescriptor(clazz->descriptor));
168    std::string actualClassName(dvmHumanReadableType(obj));
169    dvmThrowExceptionFmt(exceptionClass, "expected receiver of type %s, but got %s",
170            expectedClassName.c_str(), actualClassName.c_str());
171    return false;
172}
173
174/*
175 * Find a class by name, initializing it if requested.
176 */
177ClassObject* dvmFindClassByName(StringObject* nameObj, Object* loader,
178    bool doInit)
179{
180    ClassObject* clazz = NULL;
181    char* name = NULL;
182    char* descriptor = NULL;
183
184    if (nameObj == NULL) {
185        dvmThrowNullPointerException("name == null");
186        goto bail;
187    }
188    name = dvmCreateCstrFromString(nameObj);
189
190    /*
191     * We need to validate and convert the name (from x.y.z to x/y/z).  This
192     * is especially handy for array types, since we want to avoid
193     * auto-generating bogus array classes.
194     */
195    if (!dexIsValidClassName(name, true)) {
196        LOGW("dvmFindClassByName rejecting '%s'", name);
197        dvmThrowClassNotFoundException(name);
198        goto bail;
199    }
200
201    descriptor = dvmDotToDescriptor(name);
202    if (descriptor == NULL) {
203        goto bail;
204    }
205
206    if (doInit)
207        clazz = dvmFindClass(descriptor, loader);
208    else
209        clazz = dvmFindClassNoInit(descriptor, loader);
210
211    if (clazz == NULL) {
212        LOGVV("FAIL: load %s (%d)", descriptor, doInit);
213        Thread* self = dvmThreadSelf();
214        Object* oldExcep = dvmGetException(self);
215        dvmAddTrackedAlloc(oldExcep, self);     /* don't let this be GCed */
216        dvmClearException(self);
217        dvmThrowChainedClassNotFoundException(name, oldExcep);
218        dvmReleaseTrackedAlloc(oldExcep, self);
219    } else {
220        LOGVV("GOOD: load %s (%d) --> %p ldr=%p",
221            descriptor, doInit, clazz, clazz->classLoader);
222    }
223
224bail:
225    free(name);
226    free(descriptor);
227    return clazz;
228}
229
230/*
231 * We insert native method stubs for abstract methods so we don't have to
232 * check the access flags at the time of the method call.  This results in
233 * "native abstract" methods, which can't exist.  If we see the "abstract"
234 * flag set, clear the "native" flag.
235 *
236 * We also move the DECLARED_SYNCHRONIZED flag into the SYNCHRONIZED
237 * position, because the callers of this function are trying to convey
238 * the "traditional" meaning of the flags to their callers.
239 */
240u4 dvmFixMethodFlags(u4 flags)
241{
242    if ((flags & ACC_ABSTRACT) != 0) {
243        flags &= ~ACC_NATIVE;
244    }
245
246    flags &= ~ACC_SYNCHRONIZED;
247
248    if ((flags & ACC_DECLARED_SYNCHRONIZED) != 0) {
249        flags |= ACC_SYNCHRONIZED;
250    }
251
252    return flags & JAVA_FLAGS_MASK;
253}
254