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/*
* Copyright (C) 2007 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* JNI helper functions.
*
* This file may be included by C or C++ code, which is trouble because jni.h
* uses different typedefs for JNIEnv in each language.
*
* TODO: remove C support.
*/
#ifndef NATIVEHELPER_JNIHELP_H_
#define NATIVEHELPER_JNIHELP_H_
#include "jni.h"
#include <errno.h>
#include <unistd.h>
#ifndef NELEM
# define NELEM(x) ((int) (sizeof(x) / sizeof((x)[0])))
#endif
#ifdef __cplusplus
extern "C" {
#endif
/*
* Register one or more native methods with a particular class.
* "className" looks like "java/lang/String". Aborts on failure.
* TODO: fix all callers and change the return type to void.
*/
int jniRegisterNativeMethods(C_JNIEnv* env, const char* className, const JNINativeMethod* gMethods, int numMethods);
/*
* Throw an exception with the specified class and an optional message.
*
* The "className" argument will be passed directly to FindClass, which
* takes strings with slashes (e.g. "java/lang/Object").
*
* If an exception is currently pending, we log a warning message and
* clear it.
*
* Returns 0 on success, nonzero if something failed (e.g. the exception
* class couldn't be found, so *an* exception will still be pending).
*
* Currently aborts the VM if it can't throw the exception.
*/
int jniThrowException(C_JNIEnv* env, const char* className, const char* msg);
/*
* Throw a java.lang.NullPointerException, with an optional message.
*/
int jniThrowNullPointerException(C_JNIEnv* env, const char* msg);
/*
* Throw a java.lang.RuntimeException, with an optional message.
*/
int jniThrowRuntimeException(C_JNIEnv* env, const char* msg);
/*
* Throw a java.io.IOException, generating the message from errno.
*/
int jniThrowIOException(C_JNIEnv* env, int errnum);
/*
* Return a pointer to a locale-dependent error string explaining errno
* value 'errnum'. The returned pointer may or may not be equal to 'buf'.
* This function is thread-safe (unlike strerror) and portable (unlike
* strerror_r).
*/
const char* jniStrError(int errnum, char* buf, size_t buflen);
/*
* Returns a new java.io.FileDescriptor for the given int fd.
*/
jobject jniCreateFileDescriptor(C_JNIEnv* env, int fd);
/*
* Returns the int fd from a java.io.FileDescriptor.
*/
int jniGetFDFromFileDescriptor(C_JNIEnv* env, jobject fileDescriptor);
/*
* Sets the int fd in a java.io.FileDescriptor.
*/
void jniSetFileDescriptorOfFD(C_JNIEnv* env, jobject fileDescriptor, int value);
/*
* Returns the reference from a java.lang.ref.Reference.
*/
jobject jniGetReferent(C_JNIEnv* env, jobject ref);
/*
* Log a message and an exception.
* If exception is NULL, logs the current exception in the JNI environment.
*/
void jniLogException(C_JNIEnv* env, int priority, const char* tag, jthrowable exception);
#ifdef __cplusplus
}
#endif
/*
* For C++ code, we provide inlines that map to the C functions. g++ always
* inlines these, even on non-optimized builds.
*/
#if defined(__cplusplus)
inline int jniRegisterNativeMethods(JNIEnv* env, const char* className, const JNINativeMethod* gMethods, int numMethods) {
return jniRegisterNativeMethods(&env->functions, className, gMethods, numMethods);
}
inline int jniThrowException(JNIEnv* env, const char* className, const char* msg) {
return jniThrowException(&env->functions, className, msg);
}
extern "C" int jniThrowExceptionFmt(C_JNIEnv* env, const char* className, const char* fmt, va_list args);
/*
* Equivalent to jniThrowException but with a printf-like format string and
* variable-length argument list. This is only available in C++.
*/
inline int jniThrowExceptionFmt(JNIEnv* env, const char* className, const char* fmt, ...) {
va_list args;
va_start(args, fmt);
return jniThrowExceptionFmt(&env->functions, className, fmt, args);
va_end(args);
}
inline int jniThrowNullPointerException(JNIEnv* env, const char* msg) {
return jniThrowNullPointerException(&env->functions, msg);
}
inline int jniThrowRuntimeException(JNIEnv* env, const char* msg) {
return jniThrowRuntimeException(&env->functions, msg);
}
inline int jniThrowIOException(JNIEnv* env, int errnum) {
return jniThrowIOException(&env->functions, errnum);
}
inline jobject jniCreateFileDescriptor(JNIEnv* env, int fd) {
return jniCreateFileDescriptor(&env->functions, fd);
}
inline int jniGetFDFromFileDescriptor(JNIEnv* env, jobject fileDescriptor) {
return jniGetFDFromFileDescriptor(&env->functions, fileDescriptor);
}
inline void jniSetFileDescriptorOfFD(JNIEnv* env, jobject fileDescriptor, int value) {
jniSetFileDescriptorOfFD(&env->functions, fileDescriptor, value);
}
inline jobject jniGetReferent(JNIEnv* env, jobject ref) {
return jniGetReferent(&env->functions, ref);
}
inline void jniLogException(JNIEnv* env, int priority, const char* tag, jthrowable exception = NULL) {
jniLogException(&env->functions, priority, tag, exception);
}
#endif
/*
* TEMP_FAILURE_RETRY is defined by some, but not all, versions of
* <unistd.h>. (Alas, it is not as standard as we'd hoped!) So, if it's
* not already defined, then define it here.
*/
#ifndef TEMP_FAILURE_RETRY
/* Used to retry syscalls that can return EINTR. */
#define TEMP_FAILURE_RETRY(exp) ({ \
typeof (exp) _rc; \
do { \
_rc = (exp); \
} while (_rc == -1 && errno == EINTR); \
_rc; })
#endif
#endif /* NATIVEHELPER_JNIHELP_H_ */