summaryrefslogtreecommitdiffstats
path: root/core/jni/android_os_MessageQueue.cpp
blob: d2e5462951b3f183bb5268f8891d9ca0179c5fdc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
/*
 * Copyright (C) 2010 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.
 */

#define LOG_TAG "MessageQueue-JNI"

#include "JNIHelp.h"

#include <utils/Looper.h>
#include <utils/Log.h>
#include "android_os_MessageQueue.h"

namespace android {

// ----------------------------------------------------------------------------

static struct {
    jclass clazz;

    jfieldID mPtr;   // native object attached to the DVM MessageQueue
} gMessageQueueClassInfo;

// ----------------------------------------------------------------------------

class NativeMessageQueue {
public:
    NativeMessageQueue();
    ~NativeMessageQueue();

    inline sp<Looper> getLooper() { return mLooper; }

    void pollOnce(int timeoutMillis);
    void wake();

private:
    sp<Looper> mLooper;
};

// ----------------------------------------------------------------------------

NativeMessageQueue::NativeMessageQueue() {
    mLooper = Looper::getForThread();
    if (mLooper == NULL) {
        mLooper = new Looper(false);
        Looper::setForThread(mLooper);
    }
}

NativeMessageQueue::~NativeMessageQueue() {
}

void NativeMessageQueue::pollOnce(int timeoutMillis) {
    mLooper->pollOnce(timeoutMillis);
}

void NativeMessageQueue::wake() {
    mLooper->wake();
}

// ----------------------------------------------------------------------------

static NativeMessageQueue* android_os_MessageQueue_getNativeMessageQueue(JNIEnv* env,
        jobject messageQueueObj) {
    jint intPtr = env->GetIntField(messageQueueObj, gMessageQueueClassInfo.mPtr);
    return reinterpret_cast<NativeMessageQueue*>(intPtr);
}

static void android_os_MessageQueue_setNativeMessageQueue(JNIEnv* env, jobject messageQueueObj,
        NativeMessageQueue* nativeMessageQueue) {
    env->SetIntField(messageQueueObj, gMessageQueueClassInfo.mPtr,
             reinterpret_cast<jint>(nativeMessageQueue));
}

sp<Looper> android_os_MessageQueue_getLooper(JNIEnv* env, jobject messageQueueObj) {
    NativeMessageQueue* nativeMessageQueue =
            android_os_MessageQueue_getNativeMessageQueue(env, messageQueueObj);
    return nativeMessageQueue != NULL ? nativeMessageQueue->getLooper() : NULL;
}

static void android_os_MessageQueue_nativeInit(JNIEnv* env, jobject obj) {
    NativeMessageQueue* nativeMessageQueue = new NativeMessageQueue();
    if (! nativeMessageQueue) {
        jniThrowRuntimeException(env, "Unable to allocate native queue");
        return;
    }

    android_os_MessageQueue_setNativeMessageQueue(env, obj, nativeMessageQueue);
}

static void android_os_MessageQueue_nativeDestroy(JNIEnv* env, jobject obj) {
    NativeMessageQueue* nativeMessageQueue =
            android_os_MessageQueue_getNativeMessageQueue(env, obj);
    if (nativeMessageQueue) {
        android_os_MessageQueue_setNativeMessageQueue(env, obj, NULL);
        delete nativeMessageQueue;
    }
}

static void throwQueueNotInitialized(JNIEnv* env) {
    jniThrowException(env, "java/lang/IllegalStateException", "Message queue not initialized");
}

static void android_os_MessageQueue_nativePollOnce(JNIEnv* env, jobject obj,
        jint ptr, jint timeoutMillis) {
    NativeMessageQueue* nativeMessageQueue = reinterpret_cast<NativeMessageQueue*>(ptr);
    nativeMessageQueue->pollOnce(timeoutMillis);
}

static void android_os_MessageQueue_nativeWake(JNIEnv* env, jobject obj, jint ptr) {
    NativeMessageQueue* nativeMessageQueue = reinterpret_cast<NativeMessageQueue*>(ptr);
    return nativeMessageQueue->wake();
}

// ----------------------------------------------------------------------------

static JNINativeMethod gMessageQueueMethods[] = {
    /* name, signature, funcPtr */
    { "nativeInit", "()V", (void*)android_os_MessageQueue_nativeInit },
    { "nativeDestroy", "()V", (void*)android_os_MessageQueue_nativeDestroy },
    { "nativePollOnce", "(II)V", (void*)android_os_MessageQueue_nativePollOnce },
    { "nativeWake", "(I)V", (void*)android_os_MessageQueue_nativeWake }
};

#define FIND_CLASS(var, className) \
        var = env->FindClass(className); \
        LOG_FATAL_IF(! var, "Unable to find class " className); \
        var = jclass(env->NewGlobalRef(var));

#define GET_FIELD_ID(var, clazz, fieldName, fieldDescriptor) \
        var = env->GetFieldID(clazz, fieldName, fieldDescriptor); \
        LOG_FATAL_IF(! var, "Unable to find field " fieldName);

int register_android_os_MessageQueue(JNIEnv* env) {
    int res = jniRegisterNativeMethods(env, "android/os/MessageQueue",
            gMessageQueueMethods, NELEM(gMessageQueueMethods));
    LOG_FATAL_IF(res < 0, "Unable to register native methods.");

    FIND_CLASS(gMessageQueueClassInfo.clazz, "android/os/MessageQueue");

    GET_FIELD_ID(gMessageQueueClassInfo.mPtr, gMessageQueueClassInfo.clazz,
            "mPtr", "I");
    
    return 0;
}

} // namespace android