android_frameworks_base/native/android/looper.cpp

/*
 * 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 "ALooper"
#include <utils/Log.h>

#include <android/looper.h>
#include <utils/PollLoop.h>

using android::PollLoop;
using android::sp;

ALooper* ALooper_forThread() {
    return PollLoop::getForThread().get();
}

ALooper* ALooper_prepare(int32_t opts) {
    bool allowFds = (opts&ALOOPER_PREPARE_ALLOW_NON_CALLBACKS) != 0;
    sp<PollLoop> loop = PollLoop::getForThread();
    if (loop == NULL) {
        loop = new PollLoop(allowFds);
        PollLoop::setForThread(loop);
    }
    if (loop->getAllowNonCallbacks() != allowFds) {
        LOGW("ALooper_prepare again with different ALOOPER_PREPARE_ALLOW_NON_CALLBACKS");
    }
    return loop.get();
}

int32_t ALooper_pollOnce(int timeoutMillis, int* outEvents, void** outData) {
    sp<PollLoop> loop = PollLoop::getForThread();
    if (loop == NULL) {
        LOGW("ALooper_pollOnce: No looper for this thread!");
        return -1;
    }
    return loop->pollOnce(timeoutMillis, outEvents, outData);
}

int32_t ALooper_pollAll(int timeoutMillis, int* outEvents, void** outData) {
    sp<PollLoop> loop = PollLoop::getForThread();
    if (loop == NULL) {
        LOGW("ALooper_pollOnce: No looper for this thread!");
        return -1;
    }
    
    int32_t result;
    while ((result = loop->pollOnce(timeoutMillis, outEvents, outData)) == ALOOPER_POLL_CALLBACK) {
        ;
    }
    
    return result;
}

void ALooper_acquire(ALooper* looper) {
    static_cast<PollLoop*>(looper)->incStrong((void*)ALooper_acquire);
}

void ALooper_release(ALooper* looper) {
    static_cast<PollLoop*>(looper)->decStrong((void*)ALooper_acquire);
}

void ALooper_addFd(ALooper* looper, int fd, int ident, int events,
        ALooper_callbackFunc* callback, void* data) {
    static_cast<PollLoop*>(looper)->setLooperCallback(fd, ident, events, callback, data);
}

int32_t ALooper_removeFd(ALooper* looper, int fd) {
    return static_cast<PollLoop*>(looper)->removeCallback(fd) ? 1 : 0;
}