Native.h revision a6e94ff55517438569d207e3ed552c8c127bcac9 
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 * Dalvik's native call interface.
18 *
19 * You should follow the JNI function naming conventions, but prefix with
20 * "Dalvik_" instead of "Java_".
21 */
22#ifndef DALVIK_NATIVE_H_
23#define DALVIK_NATIVE_H_
24
25/*
26 * Method description; equivalent to a JNI struct.
27 */
28struct DalvikNativeMethod {
29    const char* name;
30    const char* signature;
31    DalvikNativeFunc  fnPtr;
32};
33
34/*
35 * All methods for one class.  The last "methodInfo" has a NULL "name".
36 */
37struct DalvikNativeClass {
38    const char* classDescriptor;
39    const DalvikNativeMethod* methodInfo;
40    u4          classDescriptorHash;          /* initialized at runtime */
41};
42
43
44/* init/shutdown */
45bool dvmNativeStartup(void);
46void dvmNativeShutdown(void);
47
48
49/*
50 * Convert argc/argv into a function call.  This is platform-specific.
51 */
52extern "C" void dvmPlatformInvoke(void* pEnv, ClassObject* clazz, int argInfo,
53    int argc, const u4* argv, const char* signature, void* func, JValue* pResult);
54
55/*
56 * Generate hints to speed native calls.  This is platform specific.
57 */
58u4 dvmPlatformInvokeHints(const DexProto* proto);
59
60/*
61 * Convert a short library name ("jpeg") to a system-dependent name
62 * ("libjpeg.so").  Returns a newly-allocated string.
63 */
64char* dvmCreateSystemLibraryName(char* libName);
65bool dvmLoadNativeCode(const char* fileName, Object* classLoader,
66        char** detail);
67
68
69/*
70 * Resolve a native method.  This uses the same prototype as a
71 * DalvikBridgeFunc, because it takes the place of the actual function
72 * until the first time that it's invoked.
73 *
74 * Causes the method's class to be initialized.
75 *
76 * Throws an exception and returns NULL on failure.
77 */
78void dvmResolveNativeMethod(const u4* args, JValue* pResult,
79    const Method* method, struct Thread* self);
80
81/*
82 * Unregister all JNI native methods associated with a class.
83 */
84void dvmUnregisterJNINativeMethods(ClassObject* clazz);
85
86#define GET_ARG_LONG(_args, _elem)          dvmGetArgLong(_args, _elem)
87
88/*
89 * Helpful function for accessing long integers in "u4* args".
90 *
91 * We can't just return *(s8*)(&args[elem]), because that breaks if our
92 * architecture requires 64-bit alignment of 64-bit values.
93 *
94 * Big/little endian shouldn't matter here -- ordering of words within a
95 * long seems consistent across our supported platforms.
96 */
97INLINE s8 dvmGetArgLong(const u4* args, int elem)
98{
99    s8 val;
100    memcpy(&val, &args[elem], sizeof(val));
101    return val;
102}
103
104#endif  // DALVIK_NATIVE_H_
105