| /* |
| * 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 "android_nio_utils.h" |
| |
| struct NioJNIData { |
| jclass nioAccessClass; |
| |
| jmethodID getBasePointerID; |
| jmethodID getBaseArrayID; |
| jmethodID getBaseArrayOffsetID; |
| }; |
| |
| static NioJNIData gNioJNI; |
| |
| void* android::nio_getPointer(JNIEnv *_env, jobject buffer, jarray *array) { |
| assert(array); |
| |
| jlong pointer; |
| jint offset; |
| void *data; |
| |
| pointer = _env->CallStaticLongMethod(gNioJNI.nioAccessClass, |
| gNioJNI.getBasePointerID, buffer); |
| if (pointer != 0L) { |
| *array = NULL; |
| return (void *) (jint) pointer; |
| } |
| |
| *array = (jarray) _env->CallStaticObjectMethod(gNioJNI.nioAccessClass, |
| gNioJNI.getBaseArrayID, buffer); |
| offset = _env->CallStaticIntMethod(gNioJNI.nioAccessClass, |
| gNioJNI.getBaseArrayOffsetID, buffer); |
| data = _env->GetPrimitiveArrayCritical(*array, (jboolean *) 0); |
| |
| return (void *) ((char *) data + offset); |
| } |
| |
| |
| void android::nio_releasePointer(JNIEnv *_env, jarray array, void *data, |
| jboolean commit) { |
| _env->ReleasePrimitiveArrayCritical(array, data, |
| commit ? 0 : JNI_ABORT); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| android::AutoBufferPointer::AutoBufferPointer(JNIEnv* env, jobject nioBuffer, |
| jboolean commit) { |
| fEnv = env; |
| fCommit = commit; |
| fPointer = android::nio_getPointer(env, nioBuffer, &fArray); |
| } |
| |
| android::AutoBufferPointer::~AutoBufferPointer() { |
| if (NULL != fArray) { |
| android::nio_releasePointer(fEnv, fArray, fPointer, fCommit); |
| } |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| static jclass findClass(JNIEnv* env, const char name[]) { |
| jclass c = env->FindClass(name); |
| LOG_FATAL_IF(!c, "Unable to find class %s", name); |
| return c; |
| } |
| |
| static jmethodID findStaticMethod(JNIEnv* env, jclass c, const char method[], |
| const char params[]) { |
| jmethodID m = env->GetStaticMethodID(c, method, params); |
| LOG_FATAL_IF(!m, "Unable to find method %s", method); |
| return m; |
| } |
| |
| static jfieldID getFieldID(JNIEnv* env, jclass c, const char name[], |
| const char type[]) { |
| jfieldID f = env->GetFieldID(c, name, type); |
| LOG_FATAL_IF(!f, "Unable to find field %s", name); |
| return f; |
| } |
| |
| namespace android { |
| |
| int register_android_nio_utils(JNIEnv* env); |
| int register_android_nio_utils(JNIEnv* env) { |
| jclass localClass = findClass(env, "java/nio/NIOAccess"); |
| gNioJNI.getBasePointerID = findStaticMethod(env, localClass, |
| "getBasePointer", "(Ljava/nio/Buffer;)J"); |
| gNioJNI.getBaseArrayID = findStaticMethod(env, localClass, |
| "getBaseArray", "(Ljava/nio/Buffer;)Ljava/lang/Object;"); |
| gNioJNI.getBaseArrayOffsetID = findStaticMethod(env, localClass, |
| "getBaseArrayOffset", "(Ljava/nio/Buffer;)I"); |
| |
| // now record a permanent version of the class ID |
| gNioJNI.nioAccessClass = (jclass) env->NewGlobalRef(localClass); |
| |
| return 0; |
| } |
| |
| } |