• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (C) 2007 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  * JNI helper functions.
19  *
20  * This file may be included by C or C++ code, which is trouble because jni.h
21  * uses different typedefs for JNIEnv in each language.
22  */
23 #ifndef _NATIVEHELPER_JNIHELP_H
24 #define _NATIVEHELPER_JNIHELP_H
25 
26 #include "jni.h"
27 #include "utils/Log.h"
28 
29 #ifndef NELEM
30 # define NELEM(x) ((int) (sizeof(x) / sizeof((x)[0])))
31 #endif
32 
33 #ifdef __cplusplus
34 extern "C" {
35 #endif
36 
37 /*
38  * Register one or more native methods with a particular class.
39  */
40 int jniRegisterNativeMethods(C_JNIEnv* env, const char* className,
41     const JNINativeMethod* gMethods, int numMethods);
42 
43 /*
44  * Throw an exception with the specified class and an optional message.
45  * The "className" argument will be passed directly to FindClass, which
46  * takes strings with slashes (e.g. "java/lang/Object").
47  *
48  * Returns 0 on success, nonzero if something failed (e.g. the exception
49  * class couldn't be found).
50  *
51  * Currently aborts the VM if it can't throw the exception.
52  */
53 int jniThrowException(C_JNIEnv* env, const char* className, const char* msg);
54 
55 /*
56  * Throw a java.IO.IOException, generating the message from errno.
57  */
58 int jniThrowIOException(C_JNIEnv* env, int errnum);
59 
60 /*
61  * Create a java.io.FileDescriptor given an integer fd
62  */
63 jobject jniCreateFileDescriptor(C_JNIEnv* env, int fd);
64 
65 /*
66  * Get an int file descriptor from a java.io.FileDescriptor
67  */
68 int jniGetFDFromFileDescriptor(C_JNIEnv* env, jobject fileDescriptor);
69 
70 /*
71  * Set an int file descriptor to a java.io.FileDescriptor
72  */
73 void jniSetFileDescriptorOfFD(C_JNIEnv* env, jobject fileDescriptor, int value);
74 
75 #ifdef __cplusplus
76 }
77 #endif
78 
79 
80 /*
81  * For C++ code, we provide inlines that map to the C functions.  g++ always
82  * inlines these, even on non-optimized builds.
83  */
84 #if defined(__cplusplus) && !defined(JNI_FORCE_C)
jniRegisterNativeMethods(JNIEnv * env,const char * className,const JNINativeMethod * gMethods,int numMethods)85 inline int jniRegisterNativeMethods(JNIEnv* env, const char* className,
86     const JNINativeMethod* gMethods, int numMethods)
87 {
88     return jniRegisterNativeMethods(&env->functions, className, gMethods,
89         numMethods);
90 }
jniThrowException(JNIEnv * env,const char * className,const char * msg)91 inline int jniThrowException(JNIEnv* env, const char* className,
92     const char* msg)
93 {
94     return jniThrowException(&env->functions, className, msg);
95 }
jniThrowIOException(JNIEnv * env,int errnum)96 inline int jniThrowIOException(JNIEnv* env, int errnum)
97 {
98     return jniThrowIOException(&env->functions, errnum);
99 }
jniCreateFileDescriptor(JNIEnv * env,int fd)100 inline jobject jniCreateFileDescriptor(JNIEnv* env, int fd)
101 {
102     return jniCreateFileDescriptor(&env->functions, fd);
103 }
jniGetFDFromFileDescriptor(JNIEnv * env,jobject fileDescriptor)104 inline int jniGetFDFromFileDescriptor(JNIEnv* env, jobject fileDescriptor)
105 {
106     return jniGetFDFromFileDescriptor(&env->functions, fileDescriptor);
107 }
jniSetFileDescriptorOfFD(JNIEnv * env,jobject fileDescriptor,int value)108 inline void jniSetFileDescriptorOfFD(JNIEnv* env, jobject fileDescriptor,
109     int value)
110 {
111     return jniSetFileDescriptorOfFD(&env->functions, fileDescriptor, value);
112 }
113 #endif
114 
115 #endif /*_NATIVEHELPER_JNIHELP_H*/
116