1 /*
2 * Copyright (C) 2010 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 #define LOG_TAG "MessageQueue-JNI"
18
19 #include "JNIHelp.h"
20
21 #include <utils/Looper.h>
22 #include <utils/Log.h>
23 #include "android_os_MessageQueue.h"
24
25 namespace android {
26
27 // ----------------------------------------------------------------------------
28
29 static struct {
30 jfieldID mPtr; // native object attached to the DVM MessageQueue
31 } gMessageQueueClassInfo;
32
33 // ----------------------------------------------------------------------------
34
35 class NativeMessageQueue {
36 public:
37 NativeMessageQueue();
38 ~NativeMessageQueue();
39
getLooper()40 inline sp<Looper> getLooper() { return mLooper; }
41
42 void pollOnce(int timeoutMillis);
43 void wake();
44
45 private:
46 sp<Looper> mLooper;
47 };
48
49 // ----------------------------------------------------------------------------
50
NativeMessageQueue()51 NativeMessageQueue::NativeMessageQueue() {
52 mLooper = Looper::getForThread();
53 if (mLooper == NULL) {
54 mLooper = new Looper(false);
55 Looper::setForThread(mLooper);
56 }
57 }
58
~NativeMessageQueue()59 NativeMessageQueue::~NativeMessageQueue() {
60 }
61
pollOnce(int timeoutMillis)62 void NativeMessageQueue::pollOnce(int timeoutMillis) {
63 mLooper->pollOnce(timeoutMillis);
64 }
65
wake()66 void NativeMessageQueue::wake() {
67 mLooper->wake();
68 }
69
70 // ----------------------------------------------------------------------------
71
android_os_MessageQueue_getNativeMessageQueue(JNIEnv * env,jobject messageQueueObj)72 static NativeMessageQueue* android_os_MessageQueue_getNativeMessageQueue(JNIEnv* env,
73 jobject messageQueueObj) {
74 jint intPtr = env->GetIntField(messageQueueObj, gMessageQueueClassInfo.mPtr);
75 return reinterpret_cast<NativeMessageQueue*>(intPtr);
76 }
77
android_os_MessageQueue_setNativeMessageQueue(JNIEnv * env,jobject messageQueueObj,NativeMessageQueue * nativeMessageQueue)78 static void android_os_MessageQueue_setNativeMessageQueue(JNIEnv* env, jobject messageQueueObj,
79 NativeMessageQueue* nativeMessageQueue) {
80 env->SetIntField(messageQueueObj, gMessageQueueClassInfo.mPtr,
81 reinterpret_cast<jint>(nativeMessageQueue));
82 }
83
android_os_MessageQueue_getLooper(JNIEnv * env,jobject messageQueueObj)84 sp<Looper> android_os_MessageQueue_getLooper(JNIEnv* env, jobject messageQueueObj) {
85 NativeMessageQueue* nativeMessageQueue =
86 android_os_MessageQueue_getNativeMessageQueue(env, messageQueueObj);
87 return nativeMessageQueue != NULL ? nativeMessageQueue->getLooper() : NULL;
88 }
89
android_os_MessageQueue_nativeInit(JNIEnv * env,jobject obj)90 static void android_os_MessageQueue_nativeInit(JNIEnv* env, jobject obj) {
91 NativeMessageQueue* nativeMessageQueue = new NativeMessageQueue();
92 if (! nativeMessageQueue) {
93 jniThrowRuntimeException(env, "Unable to allocate native queue");
94 return;
95 }
96
97 android_os_MessageQueue_setNativeMessageQueue(env, obj, nativeMessageQueue);
98 }
99
android_os_MessageQueue_nativeDestroy(JNIEnv * env,jobject obj)100 static void android_os_MessageQueue_nativeDestroy(JNIEnv* env, jobject obj) {
101 NativeMessageQueue* nativeMessageQueue =
102 android_os_MessageQueue_getNativeMessageQueue(env, obj);
103 if (nativeMessageQueue) {
104 android_os_MessageQueue_setNativeMessageQueue(env, obj, NULL);
105 delete nativeMessageQueue;
106 }
107 }
108
throwQueueNotInitialized(JNIEnv * env)109 static void throwQueueNotInitialized(JNIEnv* env) {
110 jniThrowException(env, "java/lang/IllegalStateException", "Message queue not initialized");
111 }
112
android_os_MessageQueue_nativePollOnce(JNIEnv * env,jobject obj,jint ptr,jint timeoutMillis)113 static void android_os_MessageQueue_nativePollOnce(JNIEnv* env, jobject obj,
114 jint ptr, jint timeoutMillis) {
115 NativeMessageQueue* nativeMessageQueue = reinterpret_cast<NativeMessageQueue*>(ptr);
116 nativeMessageQueue->pollOnce(timeoutMillis);
117 }
118
android_os_MessageQueue_nativeWake(JNIEnv * env,jobject obj,jint ptr)119 static void android_os_MessageQueue_nativeWake(JNIEnv* env, jobject obj, jint ptr) {
120 NativeMessageQueue* nativeMessageQueue = reinterpret_cast<NativeMessageQueue*>(ptr);
121 return nativeMessageQueue->wake();
122 }
123
124 // ----------------------------------------------------------------------------
125
126 static JNINativeMethod gMessageQueueMethods[] = {
127 /* name, signature, funcPtr */
128 { "nativeInit", "()V", (void*)android_os_MessageQueue_nativeInit },
129 { "nativeDestroy", "()V", (void*)android_os_MessageQueue_nativeDestroy },
130 { "nativePollOnce", "(II)V", (void*)android_os_MessageQueue_nativePollOnce },
131 { "nativeWake", "(I)V", (void*)android_os_MessageQueue_nativeWake }
132 };
133
134 #define FIND_CLASS(var, className) \
135 var = env->FindClass(className); \
136 LOG_FATAL_IF(! var, "Unable to find class " className);
137
138 #define GET_FIELD_ID(var, clazz, fieldName, fieldDescriptor) \
139 var = env->GetFieldID(clazz, fieldName, fieldDescriptor); \
140 LOG_FATAL_IF(! var, "Unable to find field " fieldName);
141
register_android_os_MessageQueue(JNIEnv * env)142 int register_android_os_MessageQueue(JNIEnv* env) {
143 int res = jniRegisterNativeMethods(env, "android/os/MessageQueue",
144 gMessageQueueMethods, NELEM(gMessageQueueMethods));
145 LOG_FATAL_IF(res < 0, "Unable to register native methods.");
146
147 jclass clazz;
148 FIND_CLASS(clazz, "android/os/MessageQueue");
149
150 GET_FIELD_ID(gMessageQueueClassInfo.mPtr, clazz,
151 "mPtr", "I");
152
153 return 0;
154 }
155
156 } // namespace android
157