host/frontend/gcastv2/libandroid/AnotherPacketSource.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.
 */

#include <media/stagefright/AnotherPacketSource.h>

#include <media/stagefright/foundation/ABuffer.h>
#include <media/stagefright/foundation/ADebug.h>
#include <media/stagefright/foundation/AMessage.h>
#include <media/stagefright/foundation/hexdump.h>
#include <media/stagefright/MediaBuffer.h>
#include <media/stagefright/MediaDefs.h>
#include <media/stagefright/MediaErrors.h>
#include <media/stagefright/MetaData.h>

namespace android {

const int64_t kNearEOSMarkUs = 2000000ll; // 2 secs

AnotherPacketSource::AnotherPacketSource(const std::shared_ptr<MetaData> &meta)
    : mIsAudio(false),
      mFormat(meta),
      mLastQueuedTimeUs(0),
      mEOSResult(OK) {
    const char *mime;
    CHECK(meta->findCString(kKeyMIMEType, &mime));

    if (!strncasecmp("audio/", mime, 6)) {
        mIsAudio = true;
    } else {
        CHECK(!strncasecmp("video/", mime, 6));
    }
}

void AnotherPacketSource::setFormat(const std::shared_ptr<MetaData> &meta) {
    CHECK(mFormat == NULL);
    mFormat = meta;
}

AnotherPacketSource::~AnotherPacketSource() {
}

status_t AnotherPacketSource::start(MetaData * /* params */) {
    return OK;
}

status_t AnotherPacketSource::stop() {
    return OK;
}

std::shared_ptr<MetaData> AnotherPacketSource::getFormat() {
    return mFormat;
}

status_t AnotherPacketSource::dequeueAccessUnit(std::shared_ptr<ABuffer> *buffer) {
    buffer->reset();

    Mutex::Autolock autoLock(mLock);
    while (mEOSResult == OK && mBuffers.empty()) {
        mCondition.wait(mLock);
    }

    if (!mBuffers.empty()) {
        *buffer = *mBuffers.begin();
        mBuffers.erase(mBuffers.begin());

        int32_t discontinuity;
        if ((*buffer)->meta()->findInt32("discontinuity", &discontinuity)) {
            if (wasFormatChange(discontinuity)) {
                mFormat.reset();
            }

            return INFO_DISCONTINUITY;
        }

        return OK;
    }

    return mEOSResult;
}

status_t AnotherPacketSource::read(
        MediaBuffer **out, const ReadOptions *) {
    *out = NULL;

    Mutex::Autolock autoLock(mLock);
    while (mEOSResult == OK && mBuffers.empty()) {
        mCondition.wait(mLock);
    }

    if (!mBuffers.empty()) {
        const std::shared_ptr<ABuffer> buffer = *mBuffers.begin();
        mBuffers.erase(mBuffers.begin());

        int32_t discontinuity;
        if (buffer->meta()->findInt32("discontinuity", &discontinuity)) {
            if (wasFormatChange(discontinuity)) {
                mFormat.reset();
            }

            return INFO_DISCONTINUITY;
        } else {
            int64_t timeUs;
            CHECK(buffer->meta()->findInt64("timeUs", &timeUs));

            MediaBuffer *mediaBuffer = new MediaBuffer(buffer->size());
            memcpy(mediaBuffer->data(), buffer->data(), buffer->size());

            mediaBuffer->meta_data()->setInt64(kKeyTime, timeUs);

            *out = mediaBuffer;
            return OK;
        }
    }

    return mEOSResult;
}

bool AnotherPacketSource::wasFormatChange(
        int32_t discontinuityType) const {
    if (mIsAudio) {
        return (discontinuityType & ATSParser::DISCONTINUITY_AUDIO_FORMAT) != 0;
    }

    return (discontinuityType & ATSParser::DISCONTINUITY_VIDEO_FORMAT) != 0;
}

void AnotherPacketSource::queueAccessUnit(const std::shared_ptr<ABuffer> &buffer) {
    int32_t damaged;
    if (buffer->meta()->findInt32("damaged", &damaged) && damaged) {
        // LOG(VERBOSE) << "discarding damaged AU";
        return;
    }

    CHECK(buffer->meta()->findInt64("timeUs", &mLastQueuedTimeUs));
    ALOGV("queueAccessUnit timeUs=%lld us (%.2f secs)", mLastQueuedTimeUs, mLastQueuedTimeUs / 1E6);

    Mutex::Autolock autoLock(mLock);
    mBuffers.push_back(buffer);
    mCondition.signal();
}

void AnotherPacketSource::queueDiscontinuity(
        ATSParser::DiscontinuityType type,
        const std::shared_ptr<AMessage> &extra) {
    Mutex::Autolock autoLock(mLock);

    // Leave only discontinuities in the queue.
    auto it = mBuffers.begin();
    while (it != mBuffers.end()) {
        std::shared_ptr<ABuffer> oldBuffer = *it;

        int32_t oldDiscontinuityType;
        if (!oldBuffer->meta()->findInt32(
                    "discontinuity", &oldDiscontinuityType)) {
            it = mBuffers.erase(it);
            continue;
        }

        ++it;
    }

    mEOSResult = OK;
    mLastQueuedTimeUs = 0;

    std::shared_ptr<ABuffer> buffer(new ABuffer(0));
    buffer->meta()->setInt32("discontinuity", static_cast<int32_t>(type));
    buffer->meta()->setMessage("extra", extra);

    mBuffers.push_back(buffer);
    mCondition.signal();
}

void AnotherPacketSource::signalEOS(status_t result) {
    CHECK(result != OK);

    Mutex::Autolock autoLock(mLock);
    mEOSResult = result;
    mCondition.signal();
}

bool AnotherPacketSource::hasBufferAvailable(status_t *finalResult) {
    Mutex::Autolock autoLock(mLock);
    if (!mBuffers.empty()) {
        return true;
    }

    *finalResult = mEOSResult;
    return false;
}

int64_t AnotherPacketSource::getBufferedDurationUs(status_t *finalResult) {
    Mutex::Autolock autoLock(mLock);

    *finalResult = mEOSResult;

    if (mBuffers.empty()) {
        return 0;
    }

    int64_t time1 = -1;
    int64_t time2 = -1;

    auto it = mBuffers.begin();
    while (it != mBuffers.end()) {
        const std::shared_ptr<ABuffer> &buffer = *it;

        int64_t timeUs;
        if (buffer->meta()->findInt64("timeUs", &timeUs)) {
            if (time1 < 0) {
                time1 = timeUs;
            }

            time2 = timeUs;
        } else {
            // This is a discontinuity, reset everything.
            time1 = time2 = -1;
        }

        ++it;
    }

    return time2 - time1;
}

status_t AnotherPacketSource::nextBufferTime(int64_t *timeUs) {
    *timeUs = 0;

    Mutex::Autolock autoLock(mLock);

    if (mBuffers.empty()) {
        return mEOSResult != OK ? mEOSResult : -EWOULDBLOCK;
    }

    std::shared_ptr<ABuffer> buffer = *mBuffers.begin();
    CHECK(buffer->meta()->findInt64("timeUs", timeUs));

    return OK;
}

bool AnotherPacketSource::isFinished(int64_t duration) const {
    if (duration > 0) {
        int64_t diff = duration - mLastQueuedTimeUs;
        if (diff < kNearEOSMarkUs && diff > -kNearEOSMarkUs) {
            ALOGV("Detecting EOS due to near end");
            return true;
        }
    }
    return (mEOSResult != OK);
}

}  // namespace android