The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 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 | #include "android_nio_utils.h" |
| 18 | |
| 19 | struct NioJNIData { |
| 20 | jclass nioAccessClass; |
| 21 | |
| 22 | jmethodID getBasePointerID; |
| 23 | jmethodID getBaseArrayID; |
| 24 | jmethodID getBaseArrayOffsetID; |
| 25 | }; |
| 26 | |
| 27 | static NioJNIData gNioJNI; |
| 28 | |
| 29 | void* android::nio_getPointer(JNIEnv *_env, jobject buffer, jarray *array) { |
| 30 | assert(array); |
| 31 | |
| 32 | jlong pointer; |
| 33 | jint offset; |
| 34 | void *data; |
Elliott Hughes | dd66bcb | 2011-04-12 11:28:59 -0700 | [diff] [blame] | 35 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 36 | pointer = _env->CallStaticLongMethod(gNioJNI.nioAccessClass, |
| 37 | gNioJNI.getBasePointerID, buffer); |
| 38 | if (pointer != 0L) { |
| 39 | *array = NULL; |
Ashok Bhat | f5df700 | 2014-03-25 20:51:35 +0000 | [diff] [blame] | 40 | return reinterpret_cast<void *>(pointer); |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 41 | } |
Elliott Hughes | dd66bcb | 2011-04-12 11:28:59 -0700 | [diff] [blame] | 42 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 43 | *array = (jarray) _env->CallStaticObjectMethod(gNioJNI.nioAccessClass, |
| 44 | gNioJNI.getBaseArrayID, buffer); |
| 45 | offset = _env->CallStaticIntMethod(gNioJNI.nioAccessClass, |
| 46 | gNioJNI.getBaseArrayOffsetID, buffer); |
| 47 | data = _env->GetPrimitiveArrayCritical(*array, (jboolean *) 0); |
Elliott Hughes | dd66bcb | 2011-04-12 11:28:59 -0700 | [diff] [blame] | 48 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 49 | return (void *) ((char *) data + offset); |
| 50 | } |
| 51 | |
| 52 | |
| 53 | void android::nio_releasePointer(JNIEnv *_env, jarray array, void *data, |
| 54 | jboolean commit) { |
| 55 | _env->ReleasePrimitiveArrayCritical(array, data, |
| 56 | commit ? 0 : JNI_ABORT); |
| 57 | } |
| 58 | |
| 59 | /////////////////////////////////////////////////////////////////////////////// |
| 60 | |
| 61 | android::AutoBufferPointer::AutoBufferPointer(JNIEnv* env, jobject nioBuffer, |
| 62 | jboolean commit) { |
| 63 | fEnv = env; |
| 64 | fCommit = commit; |
| 65 | fPointer = android::nio_getPointer(env, nioBuffer, &fArray); |
| 66 | } |
| 67 | |
| 68 | android::AutoBufferPointer::~AutoBufferPointer() { |
| 69 | if (NULL != fArray) { |
| 70 | android::nio_releasePointer(fEnv, fArray, fPointer, fCommit); |
| 71 | } |
| 72 | } |
| 73 | |
| 74 | /////////////////////////////////////////////////////////////////////////////// |
| 75 | |
| 76 | static jclass findClass(JNIEnv* env, const char name[]) { |
| 77 | jclass c = env->FindClass(name); |
| 78 | LOG_FATAL_IF(!c, "Unable to find class %s", name); |
| 79 | return c; |
| 80 | } |
| 81 | |
| 82 | static jmethodID findStaticMethod(JNIEnv* env, jclass c, const char method[], |
| 83 | const char params[]) { |
| 84 | jmethodID m = env->GetStaticMethodID(c, method, params); |
| 85 | LOG_FATAL_IF(!m, "Unable to find method %s", method); |
| 86 | return m; |
| 87 | } |
| 88 | |
| 89 | static jfieldID getFieldID(JNIEnv* env, jclass c, const char name[], |
| 90 | const char type[]) { |
| 91 | jfieldID f = env->GetFieldID(c, name, type); |
| 92 | LOG_FATAL_IF(!f, "Unable to find field %s", name); |
| 93 | return f; |
| 94 | } |
| 95 | |
| 96 | namespace android { |
Elliott Hughes | dd66bcb | 2011-04-12 11:28:59 -0700 | [diff] [blame] | 97 | |
The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame] | 98 | int register_android_nio_utils(JNIEnv* env) { |
| 99 | jclass localClass = findClass(env, "java/nio/NIOAccess"); |
| 100 | gNioJNI.getBasePointerID = findStaticMethod(env, localClass, |
| 101 | "getBasePointer", "(Ljava/nio/Buffer;)J"); |
| 102 | gNioJNI.getBaseArrayID = findStaticMethod(env, localClass, |
| 103 | "getBaseArray", "(Ljava/nio/Buffer;)Ljava/lang/Object;"); |
| 104 | gNioJNI.getBaseArrayOffsetID = findStaticMethod(env, localClass, |
| 105 | "getBaseArrayOffset", "(Ljava/nio/Buffer;)I"); |
| 106 | |
| 107 | // now record a permanent version of the class ID |
| 108 | gNioJNI.nioAccessClass = (jclass) env->NewGlobalRef(localClass); |
| 109 | |
| 110 | return 0; |
| 111 | } |
| 112 | |
| 113 | } |