services/oboeservice/AAudioService.h

/*
 * Copyright (C) 2016 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.
 */

#ifndef AAUDIO_AAUDIO_SERVICE_H
#define AAUDIO_AAUDIO_SERVICE_H

#include <time.h>
#include <pthread.h>

#include <binder/BinderService.h>
#include <media/AudioClient.h>

#include <aaudio/AAudio.h>
#include <aaudio/BnAAudioService.h>

#include "binding/AAudioCommon.h"
#include "binding/AAudioBinderAdapter.h"
#include "binding/AAudioServiceInterface.h"

#include "AAudioServiceStreamBase.h"
#include "AAudioStreamTracker.h"

namespace android {

#define AAUDIO_SERVICE_NAME  "media.aaudio"
#define DEFAULT_AAUDIO_SERVICE_ID 0

class AAudioService :
    public BinderService<AAudioService>,
    public aaudio::BnAAudioService
{
    friend class BinderService<AAudioService>;

public:
    AAudioService();
    ~AAudioService() override = default;

    aaudio::AAudioServiceInterface& asAAudioServiceInterface() {
        return mAdapter;
    }

    static const char* getServiceName() { return AAUDIO_SERVICE_NAME; }

    status_t dump(int fd, const Vector<String16>& args) override;

    binder::Status registerClient(const ::android::sp<::aaudio::IAAudioClient>& client) override;

    binder::Status openStream(const ::aaudio::StreamRequest& request,
                              ::aaudio::StreamParameters* paramsOut,
                              int32_t* _aidl_return) override;

    binder::Status closeStream(int32_t streamHandle, int32_t* _aidl_return) override;

    binder::Status
    getStreamDescription(int32_t streamHandle, ::aaudio::Endpoint* endpoint,
                         int32_t* _aidl_return) override;

    binder::Status startStream(int32_t streamHandle, int32_t* _aidl_return) override;

    binder::Status pauseStream(int32_t streamHandle, int32_t* _aidl_return) override;

    binder::Status stopStream(int32_t streamHandle, int32_t* _aidl_return) override;

    binder::Status flushStream(int32_t streamHandle, int32_t* _aidl_return) override;

    binder::Status
    registerAudioThread(int32_t streamHandle, int32_t clientThreadId, int64_t periodNanoseconds,
                        int32_t* _aidl_return) override;

    binder::Status unregisterAudioThread(int32_t streamHandle, int32_t clientThreadId,
                                         int32_t* _aidl_return) override;

    binder::Status exitStandby(int32_t streamHandle, ::aaudio::Endpoint* endpoint,
                               int32_t* _aidl_return) override;

    aaudio_result_t startClient(aaudio::aaudio_handle_t streamHandle,
                                const android::AudioClient& client,
                                const audio_attributes_t *attr,
                                audio_port_handle_t *clientHandle);

    aaudio_result_t stopClient(aaudio::aaudio_handle_t streamHandle,
                                       audio_port_handle_t clientHandle);

 // ===============================================================================
 // The following public methods are only called from the service and NOT by Binder.
 // ===============================================================================

    aaudio_result_t disconnectStreamByPortHandle(audio_port_handle_t portHandle);

    /*
     * This is only called from within the Service.
     * It bypasses the permission checks in closeStream(handle).
     */
    aaudio_result_t closeStream(const sp<aaudio::AAudioServiceStreamBase>& serviceStream);

private:
    class Adapter : public aaudio::AAudioBinderAdapter {
    public:
        // Always use default service id in server side since when crash happens,
        // the aaudio service will restart.
        explicit Adapter(AAudioService *service)
                : aaudio::AAudioBinderAdapter(service, DEFAULT_AAUDIO_SERVICE_ID),
                  mService(service) {}

        aaudio_result_t startClient(const aaudio::AAudioHandleInfo& streamHandleInfo,
                                    const android::AudioClient &client,
                                    const audio_attributes_t *attr,
                                    audio_port_handle_t *clientHandle) override {
            return mService->startClient(streamHandleInfo.getHandle(), client, attr, clientHandle);
        }

        aaudio_result_t stopClient(const aaudio::AAudioHandleInfo& streamHandleInfo,
                                   audio_port_handle_t clientHandle) override {
            return mService->stopClient(streamHandleInfo.getHandle(), clientHandle);
        }

    private:
        AAudioService* const mService;
    };

    Adapter mAdapter;

    /** @return true if the client is the audioserver
     */
    bool isCallerInService();

    /**
     * Lookup stream and then validate access to the stream.
     * @param streamHandle
     * @return
     */
    sp<aaudio::AAudioServiceStreamBase> convertHandleToServiceStream(
            aaudio::aaudio_handle_t streamHandle);

    android::AudioClient            mAudioClient;

    aaudio::AAudioStreamTracker     mStreamTracker;

    // We use a lock to prevent thread A from reopening an exclusive stream
    // after thread B steals thread A's exclusive MMAP resource stream.
    std::recursive_mutex            mOpenLock;

    // TODO  Extract the priority constants from services/audioflinger/Threads.cpp
    // and share them with this code. Look for "kPriorityFastMixer".
    static constexpr int32_t        kRealTimeAudioPriorityClient = 2;
    static constexpr int32_t        kRealTimeAudioPriorityService = 3;

};

} /* namespace android */

#endif //AAUDIO_AAUDIO_SERVICE_H