• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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