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/*
* Copyright (C) 2008 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.
*/
#include "JNIHelp.h"
#include <stdlib.h>
#include <string.h>
/*
* public static native String getEnvByName(String name)
*
* (Calling it plain "getenv" might confuse GDB if you try to put a breakpoint
* on the libc version.)
*/
static jstring java_getEnvByName(JNIEnv* env, jclass, jstring nameStr) {
jstring valueStr = NULL;
if (nameStr != NULL) {
const char* name = env->GetStringUTFChars(nameStr, NULL);
const char* val = getenv(name);
if (val != NULL) {
valueStr = env->NewStringUTF(val);
}
env->ReleaseStringUTFChars(nameStr, name);
} else {
jniThrowNullPointerException(env, NULL);
}
return valueStr;
}
/*
* Pointer to complete environment, from Posix.
*/
extern char** environ;
/*
* public static native String getEnvByIndex()
*
* (Calling it plain "getenv" might confuse GDB if you try to put a breakpoint
* on the libc version.)
*/
static jstring java_getEnvByIndex(JNIEnv* env, jclass, jint index) {
jstring valueStr = NULL;
char* entry = environ[index];
if (entry != NULL) {
valueStr = env->NewStringUTF(entry);
}
return valueStr;
}
/*
* public static native String setFieldImpl()
*
* Sets a field via JNI. Used for the standard streams, which are r/o
* otherwise.
*/
static void java_setFieldImpl(JNIEnv* env, jclass clazz,
jstring name, jstring sig, jobject object) {
const char* fieldName = env->GetStringUTFChars(name, NULL);
const char* fieldSig = env->GetStringUTFChars(sig, NULL);
jfieldID fieldID = env->GetStaticFieldID(clazz, fieldName, fieldSig);
env->SetStaticObjectField(clazz, fieldID, object);
env->ReleaseStringUTFChars(name, fieldName);
env->ReleaseStringUTFChars(sig, fieldSig);
}
static JNINativeMethod gMethods[] = {
{ "getEnvByName", "(Ljava/lang/String;)Ljava/lang/String;", (void*) java_getEnvByName },
{ "getEnvByIndex", "(I)Ljava/lang/String;", (void*) java_getEnvByIndex },
{ "setFieldImpl", "(Ljava/lang/String;Ljava/lang/String;Ljava/lang/Object;)V", (void*) java_setFieldImpl },
};
int register_java_lang_System(JNIEnv* env) {
return jniRegisterNativeMethods(env, "java/lang/System", gMethods, NELEM(gMethods));
}
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