/*
 * Copyright 2012, 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_NDEBUG 0
#define LOG_TAG "MediaCodec"
#include <utils/Log.h>

#include <media/stagefright/MediaCodec.h>

#include "include/SoftwareRenderer.h"

#include <gui/Surface.h>
#include <media/ICrypto.h>
#include <media/stagefright/foundation/ABuffer.h>
#include <media/stagefright/foundation/ADebug.h>
#include <media/stagefright/foundation/AMessage.h>
#include <media/stagefright/foundation/AString.h>
#include <media/stagefright/foundation/hexdump.h>
#include <media/stagefright/ACodec.h>
#include <media/stagefright/BufferProducerWrapper.h>
#include <media/stagefright/MediaCodecList.h>
#include <media/stagefright/MediaDefs.h>
#include <media/stagefright/MediaErrors.h>
#include <media/stagefright/MetaData.h>
#include <media/stagefright/NativeWindowWrapper.h>

#include "include/avc_utils.h"

namespace android {

// static
sp<MediaCodec> MediaCodec::CreateByType(
        const sp<ALooper> &looper, const char *mime, bool encoder) {
    sp<MediaCodec> codec = new MediaCodec(looper);
    if (codec->init(mime, true /* nameIsType */, encoder) != OK) {
        return NULL;
    }

    return codec;
}

// static
sp<MediaCodec> MediaCodec::CreateByComponentName(
        const sp<ALooper> &looper, const char *name) {
    sp<MediaCodec> codec = new MediaCodec(looper);
    if (codec->init(name, false /* nameIsType */, false /* encoder */) != OK) {
        return NULL;
    }

    return codec;
}

MediaCodec::MediaCodec(const sp<ALooper> &looper)
    : mState(UNINITIALIZED),
      mLooper(looper),
      mCodec(new ACodec),
      mReplyID(0),
      mFlags(0),
      mSoftRenderer(NULL),
      mDequeueInputTimeoutGeneration(0),
      mDequeueInputReplyID(0),
      mDequeueOutputTimeoutGeneration(0),
      mDequeueOutputReplyID(0),
      mHaveInputSurface(false) {
}

MediaCodec::~MediaCodec() {
    CHECK_EQ(mState, UNINITIALIZED);
}

// static
status_t MediaCodec::PostAndAwaitResponse(
        const sp<AMessage> &msg, sp<AMessage> *response) {
    status_t err = msg->postAndAwaitResponse(response);

    if (err != OK) {
        return err;
    }

    if (!(*response)->findInt32("err", &err)) {
        err = OK;
    }

    return err;
}

status_t MediaCodec::init(const char *name, bool nameIsType, bool encoder) {
    // Current video decoders do not return from OMX_FillThisBuffer
    // quickly, violating the OpenMAX specs, until that is remedied
    // we need to invest in an extra looper to free the main event
    // queue.
    bool needDedicatedLooper = false;
    if (nameIsType && !strncasecmp(name, "video/", 6)) {
        needDedicatedLooper = true;
    } else {
        AString tmp = name;
        if (tmp.endsWith(".secure")) {
            tmp.erase(tmp.size() - 7, 7);
        }
        const MediaCodecList *mcl = MediaCodecList::getInstance();
        ssize_t codecIdx = mcl->findCodecByName(tmp.c_str());
        if (codecIdx >= 0) {
            Vector<AString> types;
            if (mcl->getSupportedTypes(codecIdx, &types) == OK) {
                for (int i = 0; i < types.size(); i++) {
                    if (types[i].startsWith("video/")) {
                        needDedicatedLooper = true;
                        break;
                    }
                }
            }
        }
    }

    if (needDedicatedLooper) {
        if (mCodecLooper == NULL) {
            mCodecLooper = new ALooper;
            mCodecLooper->setName("CodecLooper");
            mCodecLooper->start(false, false, ANDROID_PRIORITY_AUDIO);
        }

        mCodecLooper->registerHandler(mCodec);
    } else {
        mLooper->registerHandler(mCodec);
    }

    mLooper->registerHandler(this);

    mCodec->setNotificationMessage(new AMessage(kWhatCodecNotify, id()));

    sp<AMessage> msg = new AMessage(kWhatInit, id());
    msg->setString("name", name);
    msg->setInt32("nameIsType", nameIsType);

    if (nameIsType) {
        msg->setInt32("encoder", encoder);
    }

    sp<AMessage> response;
    return PostAndAwaitResponse(msg, &response);
}

status_t MediaCodec::configure(
        const sp<AMessage> &format,
        const sp<Surface> &nativeWindow,
        const sp<ICrypto> &crypto,
        uint32_t flags) {
    sp<AMessage> msg = new AMessage(kWhatConfigure, id());

    msg->setMessage("format", format);
    msg->setInt32("flags", flags);

    if (nativeWindow != NULL) {
        msg->setObject(
                "native-window",
                new NativeWindowWrapper(nativeWindow));
    }

    if (crypto != NULL) {
        msg->setPointer("crypto", crypto.get());
    }

    sp<AMessage> response;
    return PostAndAwaitResponse(msg, &response);
}

status_t MediaCodec::createInputSurface(
        sp<IGraphicBufferProducer>* bufferProducer) {
    sp<AMessage> msg = new AMessage(kWhatCreateInputSurface, id());

    sp<AMessage> response;
    status_t err = PostAndAwaitResponse(msg, &response);
    if (err == NO_ERROR) {
        // unwrap the sp<IGraphicBufferProducer>
        sp<RefBase> obj;
        bool found = response->findObject("input-surface", &obj);
        CHECK(found);
        sp<BufferProducerWrapper> wrapper(
                static_cast<BufferProducerWrapper*>(obj.get()));
        *bufferProducer = wrapper->getBufferProducer();
    } else {
        ALOGW("createInputSurface failed, err=%d", err);
    }
    return err;
}

status_t MediaCodec::start() {
    sp<AMessage> msg = new AMessage(kWhatStart, id());

    sp<AMessage> response;
    return PostAndAwaitResponse(msg, &response);
}

status_t MediaCodec::stop() {
    sp<AMessage> msg = new AMessage(kWhatStop, id());

    sp<AMessage> response;
    return PostAndAwaitResponse(msg, &response);
}

status_t MediaCodec::release() {
    sp<AMessage> msg = new AMessage(kWhatRelease, id());

    sp<AMessage> response;
    return PostAndAwaitResponse(msg, &response);
}

status_t MediaCodec::queueInputBuffer(
        size_t index,
        size_t offset,
        size_t size,
        int64_t presentationTimeUs,
        uint32_t flags,
        AString *errorDetailMsg) {
    if (errorDetailMsg != NULL) {
        errorDetailMsg->clear();
    }

    sp<AMessage> msg = new AMessage(kWhatQueueInputBuffer, id());
    msg->setSize("index", index);
    msg->setSize("offset", offset);
    msg->setSize("size", size);
    msg->setInt64("timeUs", presentationTimeUs);
    msg->setInt32("flags", flags);
    msg->setPointer("errorDetailMsg", errorDetailMsg);

    sp<AMessage> response;
    return PostAndAwaitResponse(msg, &response);
}

status_t MediaCodec::queueSecureInputBuffer(
        size_t index,
        size_t offset,
        const CryptoPlugin::SubSample *subSamples,
        size_t numSubSamples,
        const uint8_t key[16],
        const uint8_t iv[16],
        CryptoPlugin::Mode mode,
        int64_t presentationTimeUs,
        uint32_t flags,
        AString *errorDetailMsg) {
    if (errorDetailMsg != NULL) {
        errorDetailMsg->clear();
    }

    sp<AMessage> msg = new AMessage(kWhatQueueInputBuffer, id());
    msg->setSize("index", index);
    msg->setSize("offset", offset);
    msg->setPointer("subSamples", (void *)subSamples);
    msg->setSize("numSubSamples", numSubSamples);
    msg->setPointer("key", (void *)key);
    msg->setPointer("iv", (void *)iv);
    msg->setInt32("mode", mode);
    msg->setInt64("timeUs", presentationTimeUs);
    msg->setInt32("flags", flags);
    msg->setPointer("errorDetailMsg", errorDetailMsg);

    sp<AMessage> response;
    status_t err = PostAndAwaitResponse(msg, &response);

    return err;
}

status_t MediaCodec::dequeueInputBuffer(size_t *index, int64_t timeoutUs) {
    sp<AMessage> msg = new AMessage(kWhatDequeueInputBuffer, id());
    msg->setInt64("timeoutUs", timeoutUs);

    sp<AMessage> response;
    status_t err;
    if ((err = PostAndAwaitResponse(msg, &response)) != OK) {
        return err;
    }

    CHECK(response->findSize("index", index));

    return OK;
}

status_t MediaCodec::dequeueOutputBuffer(
        size_t *index,
        size_t *offset,
        size_t *size,
        int64_t *presentationTimeUs,
        uint32_t *flags,
        int64_t timeoutUs) {
    sp<AMessage> msg = new AMessage(kWhatDequeueOutputBuffer, id());
    msg->setInt64("timeoutUs", timeoutUs);

    sp<AMessage> response;
    status_t err;
    if ((err = PostAndAwaitResponse(msg, &response)) != OK) {
        return err;
    }

    CHECK(response->findSize("index", index));
    CHECK(response->findSize("offset", offset));
    CHECK(response->findSize("size", size));
    CHECK(response->findInt64("timeUs", presentationTimeUs));
    CHECK(response->findInt32("flags", (int32_t *)flags));

    return OK;
}

status_t MediaCodec::renderOutputBufferAndRelease(size_t index) {
    sp<AMessage> msg = new AMessage(kWhatReleaseOutputBuffer, id());
    msg->setSize("index", index);
    msg->setInt32("render", true);

    sp<AMessage> response;
    return PostAndAwaitResponse(msg, &response);
}

status_t MediaCodec::releaseOutputBuffer(size_t index) {
    sp<AMessage> msg = new AMessage(kWhatReleaseOutputBuffer, id());
    msg->setSize("index", index);

    sp<AMessage> response;
    return PostAndAwaitResponse(msg, &response);
}

status_t MediaCodec::signalEndOfInputStream() {
    sp<AMessage> msg = new AMessage(kWhatSignalEndOfInputStream, id());

    sp<AMessage> response;
    return PostAndAwaitResponse(msg, &response);
}

status_t MediaCodec::getOutputFormat(sp<AMessage> *format) const {
    sp<AMessage> msg = new AMessage(kWhatGetOutputFormat, id());

    sp<AMessage> response;
    status_t err;
    if ((err = PostAndAwaitResponse(msg, &response)) != OK) {
        return err;
    }

    CHECK(response->findMessage("format", format));

    return OK;
}

status_t MediaCodec::getName(AString *name) const {
    sp<AMessage> msg = new AMessage(kWhatGetName, id());

    sp<AMessage> response;
    status_t err;
    if ((err = PostAndAwaitResponse(msg, &response)) != OK) {
        return err;
    }

    CHECK(response->findString("name", name));

    return OK;
}

status_t MediaCodec::getInputBuffers(Vector<sp<ABuffer> > *buffers) const {
    sp<AMessage> msg = new AMessage(kWhatGetBuffers, id());
    msg->setInt32("portIndex", kPortIndexInput);
    msg->setPointer("buffers", buffers);

    sp<AMessage> response;
    return PostAndAwaitResponse(msg, &response);
}

status_t MediaCodec::getOutputBuffers(Vector<sp<ABuffer> > *buffers) const {
    sp<AMessage> msg = new AMessage(kWhatGetBuffers, id());
    msg->setInt32("portIndex", kPortIndexOutput);
    msg->setPointer("buffers", buffers);

    sp<AMessage> response;
    return PostAndAwaitResponse(msg, &response);
}

status_t MediaCodec::flush() {
    sp<AMessage> msg = new AMessage(kWhatFlush, id());

    sp<AMessage> response;
    return PostAndAwaitResponse(msg, &response);
}

status_t MediaCodec::requestIDRFrame() {
    (new AMessage(kWhatRequestIDRFrame, id()))->post();

    return OK;
}

void MediaCodec::requestActivityNotification(const sp<AMessage> &notify) {
    sp<AMessage> msg = new AMessage(kWhatRequestActivityNotification, id());
    msg->setMessage("notify", notify);
    msg->post();
}

////////////////////////////////////////////////////////////////////////////////

void MediaCodec::cancelPendingDequeueOperations() {
    if (mFlags & kFlagDequeueInputPending) {
        sp<AMessage> response = new AMessage;
        response->setInt32("err", INVALID_OPERATION);
        response->postReply(mDequeueInputReplyID);

        ++mDequeueInputTimeoutGeneration;
        mDequeueInputReplyID = 0;
        mFlags &= ~kFlagDequeueInputPending;
    }

    if (mFlags & kFlagDequeueOutputPending) {
        sp<AMessage> response = new AMessage;
        response->setInt32("err", INVALID_OPERATION);
        response->postReply(mDequeueOutputReplyID);

        ++mDequeueOutputTimeoutGeneration;
        mDequeueOutputReplyID = 0;
        mFlags &= ~kFlagDequeueOutputPending;
    }
}

bool MediaCodec::handleDequeueInputBuffer(uint32_t replyID, bool newRequest) {
    if (mState != STARTED
            || (mFlags & kFlagStickyError)
            || (newRequest && (mFlags & kFlagDequeueInputPending))) {
        sp<AMessage> response = new AMessage;
        response->setInt32("err", INVALID_OPERATION);

        response->postReply(replyID);

        return true;
    }

    ssize_t index = dequeuePortBuffer(kPortIndexInput);

    if (index < 0) {
        CHECK_EQ(index, -EAGAIN);
        return false;
    }

    sp<AMessage> response = new AMessage;
    response->setSize("index", index);
    response->postReply(replyID);

    return true;
}

bool MediaCodec::handleDequeueOutputBuffer(uint32_t replyID, bool newRequest) {
    sp<AMessage> response = new AMessage;

    if (mState != STARTED
            || (mFlags & kFlagStickyError)
            || (newRequest && (mFlags & kFlagDequeueOutputPending))) {
        response->setInt32("err", INVALID_OPERATION);
    } else if (mFlags & kFlagOutputBuffersChanged) {
        response->setInt32("err", INFO_OUTPUT_BUFFERS_CHANGED);
        mFlags &= ~kFlagOutputBuffersChanged;
    } else if (mFlags & kFlagOutputFormatChanged) {
        response->setInt32("err", INFO_FORMAT_CHANGED);
        mFlags &= ~kFlagOutputFormatChanged;
    } else {
        ssize_t index = dequeuePortBuffer(kPortIndexOutput);

        if (index < 0) {
            CHECK_EQ(index, -EAGAIN);
            return false;
        }

        const sp<ABuffer> &buffer =
            mPortBuffers[kPortIndexOutput].itemAt(index).mData;

        response->setSize("index", index);
        response->setSize("offset", buffer->offset());
        response->setSize("size", buffer->size());

        int64_t timeUs;
        CHECK(buffer->meta()->findInt64("timeUs", &timeUs));

        response->setInt64("timeUs", timeUs);

        int32_t omxFlags;
        CHECK(buffer->meta()->findInt32("omxFlags", &omxFlags));

        uint32_t flags = 0;
        if (omxFlags & OMX_BUFFERFLAG_SYNCFRAME) {
            flags |= BUFFER_FLAG_SYNCFRAME;
        }
        if (omxFlags & OMX_BUFFERFLAG_CODECCONFIG) {
            flags |= BUFFER_FLAG_CODECCONFIG;
        }
        if (omxFlags & OMX_BUFFERFLAG_EOS) {
            flags |= BUFFER_FLAG_EOS;
        }

        response->setInt32("flags", flags);
    }

    response->postReply(replyID);

    return true;
}

void MediaCodec::onMessageReceived(const sp<AMessage> &msg) {
    switch (msg->what()) {
        case kWhatCodecNotify:
        {
            int32_t what;
            CHECK(msg->findInt32("what", &what));

            switch (what) {
                case ACodec::kWhatError:
                {
                    int32_t omxError, internalError;
                    CHECK(msg->findInt32("omx-error", &omxError));
                    CHECK(msg->findInt32("err", &internalError));

                    ALOGE("Codec reported an error. "
                          "(omx error 0x%08x, internalError %d)",
                          omxError, internalError);

                    if (omxError == OMX_ErrorResourcesLost
                            && internalError == DEAD_OBJECT) {
                        mFlags |= kFlagSawMediaServerDie;
                    }

                    bool sendErrorReponse = true;

                    switch (mState) {
                        case INITIALIZING:
                        {
                            setState(UNINITIALIZED);
                            break;
                        }

                        case CONFIGURING:
                        {
                            setState(INITIALIZED);
                            break;
                        }

                        case STARTING:
                        {
                            setState(CONFIGURED);
                            break;
                        }

                        case STOPPING:
                        case RELEASING:
                        {
                            // Ignore the error, assuming we'll still get
                            // the shutdown complete notification.

                            sendErrorReponse = false;

                            if (mFlags & kFlagSawMediaServerDie) {
                                // MediaServer died, there definitely won't
                                // be a shutdown complete notification after
                                // all.

                                // note that we're directly going from
                                // STOPPING->UNINITIALIZED, instead of the
                                // usual STOPPING->INITIALIZED state.
                                setState(UNINITIALIZED);

                                (new AMessage)->postReply(mReplyID);
                            }
                            break;
                        }

                        case FLUSHING:
                        {
                            setState(STARTED);
                            break;
                        }

                        case STARTED:
                        {
                            sendErrorReponse = false;

                            mFlags |= kFlagStickyError;
                            postActivityNotificationIfPossible();

                            cancelPendingDequeueOperations();
                            break;
                        }

                        default:
                        {
                            sendErrorReponse = false;

                            mFlags |= kFlagStickyError;
                            postActivityNotificationIfPossible();
                            break;
                        }
                    }

                    if (sendErrorReponse) {
                        sp<AMessage> response = new AMessage;
                        response->setInt32("err", UNKNOWN_ERROR);

                        response->postReply(mReplyID);
                    }
                    break;
                }

                case ACodec::kWhatComponentAllocated:
                {
                    CHECK_EQ(mState, INITIALIZING);
                    setState(INITIALIZED);

                    CHECK(msg->findString("componentName", &mComponentName));

                    if (mComponentName.startsWith("OMX.google.")) {
                        mFlags |= kFlagIsSoftwareCodec;
                    } else {
                        mFlags &= ~kFlagIsSoftwareCodec;
                    }

                    if (mComponentName.endsWith(".secure")) {
                        mFlags |= kFlagIsSecure;
                    } else {
                        mFlags &= ~kFlagIsSecure;
                    }

                    (new AMessage)->postReply(mReplyID);
                    break;
                }

                case ACodec::kWhatComponentConfigured:
                {
                    CHECK_EQ(mState, CONFIGURING);
                    setState(CONFIGURED);

                    // reset input surface flag
                    mHaveInputSurface = false;

                    (new AMessage)->postReply(mReplyID);
                    break;
                }

                case ACodec::kWhatInputSurfaceCreated:
                {
                    // response to ACodec::kWhatCreateInputSurface
                    status_t err = NO_ERROR;
                    sp<AMessage> response = new AMessage();
                    if (!msg->findInt32("err", &err)) {
                        sp<RefBase> obj;
                        msg->findObject("input-surface", &obj);
                        CHECK(obj != NULL);
                        response->setObject("input-surface", obj);
                        mHaveInputSurface = true;
                    } else {
                        response->setInt32("err", err);
                    }
                    response->postReply(mReplyID);
                    break;
                }

                case ACodec::kWhatSignaledInputEOS:
                {
                    // response to ACodec::kWhatSignalEndOfInputStream
                    sp<AMessage> response = new AMessage();
                    status_t err;
                    if (msg->findInt32("err", &err)) {
                        response->setInt32("err", err);
                    }
                    response->postReply(mReplyID);
                    break;
                }


                case ACodec::kWhatBuffersAllocated:
                {
                    int32_t portIndex;
                    CHECK(msg->findInt32("portIndex", &portIndex));

                    ALOGV("%s buffers allocated",
                          portIndex == kPortIndexInput ? "input" : "output");

                    CHECK(portIndex == kPortIndexInput
                            || portIndex == kPortIndexOutput);

                    mPortBuffers[portIndex].clear();

                    Vector<BufferInfo> *buffers = &mPortBuffers[portIndex];

                    sp<RefBase> obj;
                    CHECK(msg->findObject("portDesc", &obj));

                    sp<ACodec::PortDescription> portDesc =
                        static_cast<ACodec::PortDescription *>(obj.get());

                    size_t numBuffers = portDesc->countBuffers();

                    for (size_t i = 0; i < numBuffers; ++i) {
                        BufferInfo info;
                        info.mBufferID = portDesc->bufferIDAt(i);
                        info.mOwnedByClient = false;
                        info.mData = portDesc->bufferAt(i);

                        if (portIndex == kPortIndexInput && mCrypto != NULL) {
                            info.mEncryptedData =
                                new ABuffer(info.mData->capacity());
                        }

                        buffers->push_back(info);
                    }

                    if (portIndex == kPortIndexOutput) {
                        if (mState == STARTING) {
                            // We're always allocating output buffers after
                            // allocating input buffers, so this is a good
                            // indication that now all buffers are allocated.
                            setState(STARTED);
                            (new AMessage)->postReply(mReplyID);
                        } else {
                            mFlags |= kFlagOutputBuffersChanged;
                            postActivityNotificationIfPossible();
                        }
                    }
                    break;
                }

                case ACodec::kWhatOutputFormatChanged:
                {
                    ALOGV("codec output format changed");

                    if ((mFlags & kFlagIsSoftwareCodec)
                            && mNativeWindow != NULL) {
                        AString mime;
                        CHECK(msg->findString("mime", &mime));

                        if (!strncasecmp("video/", mime.c_str(), 6)) {
                            delete mSoftRenderer;
                            mSoftRenderer = NULL;

                            int32_t width, height;
                            CHECK(msg->findInt32("width", &width));
                            CHECK(msg->findInt32("height", &height));

                            int32_t cropLeft, cropTop, cropRight, cropBottom;
                            CHECK(msg->findRect("crop",
                                &cropLeft, &cropTop, &cropRight, &cropBottom));

                            int32_t colorFormat;
                            CHECK(msg->findInt32(
                                        "color-format", &colorFormat));

                            sp<MetaData> meta = new MetaData;
                            meta->setInt32(kKeyWidth, width);
                            meta->setInt32(kKeyHeight, height);
                            meta->setRect(kKeyCropRect,
                                cropLeft, cropTop, cropRight, cropBottom);
                            meta->setInt32(kKeyColorFormat, colorFormat);

                            mSoftRenderer =
                                new SoftwareRenderer(mNativeWindow, meta);
                        }
                    }

                    mOutputFormat = msg;

                    if (mFlags & kFlagIsEncoder) {
                        // Before we announce the format change we should
                        // collect codec specific data and amend the output
                        // format as necessary.
                        mFlags |= kFlagGatherCodecSpecificData;
                    } else {
                        mFlags |= kFlagOutputFormatChanged;
                        postActivityNotificationIfPossible();
                    }
                    break;
                }

                case ACodec::kWhatFillThisBuffer:
                {
                    /* size_t index = */updateBuffers(kPortIndexInput, msg);

                    if (mState == FLUSHING
                            || mState == STOPPING
                            || mState == RELEASING) {
                        returnBuffersToCodecOnPort(kPortIndexInput);
                        break;
                    }

                    if (!mCSD.empty()) {
                        ssize_t index = dequeuePortBuffer(kPortIndexInput);
                        CHECK_GE(index, 0);

                        // If codec specific data had been specified as
                        // part of the format in the call to configure and
                        // if there's more csd left, we submit it here
                        // clients only get access to input buffers once
                        // this data has been exhausted.

                        status_t err = queueCSDInputBuffer(index);

                        if (err != OK) {
                            ALOGE("queueCSDInputBuffer failed w/ error %d",
                                  err);

                            mFlags |= kFlagStickyError;
                            postActivityNotificationIfPossible();

                            cancelPendingDequeueOperations();
                        }
                        break;
                    }

                    if (mFlags & kFlagDequeueInputPending) {
                        CHECK(handleDequeueInputBuffer(mDequeueInputReplyID));

                        ++mDequeueInputTimeoutGeneration;
                        mFlags &= ~kFlagDequeueInputPending;
                        mDequeueInputReplyID = 0;
                    } else {
                        postActivityNotificationIfPossible();
                    }
                    break;
                }

                case ACodec::kWhatDrainThisBuffer:
                {
                    /* size_t index = */updateBuffers(kPortIndexOutput, msg);

                    if (mState == FLUSHING
                            || mState == STOPPING
                            || mState == RELEASING) {
                        returnBuffersToCodecOnPort(kPortIndexOutput);
                        break;
                    }

                    sp<ABuffer> buffer;
                    CHECK(msg->findBuffer("buffer", &buffer));

                    int32_t omxFlags;
                    CHECK(msg->findInt32("flags", &omxFlags));

                    buffer->meta()->setInt32("omxFlags", omxFlags);

                    if (mFlags & kFlagGatherCodecSpecificData) {
                        // This is the very first output buffer after a
                        // format change was signalled, it'll either contain
                        // the one piece of codec specific data we can expect
                        // or there won't be codec specific data.
                        if (omxFlags & OMX_BUFFERFLAG_CODECCONFIG) {
                            status_t err =
                                amendOutputFormatWithCodecSpecificData(buffer);

                            if (err != OK) {
                                ALOGE("Codec spit out malformed codec "
                                      "specific data!");
                            }
                        }

                        mFlags &= ~kFlagGatherCodecSpecificData;
                        mFlags |= kFlagOutputFormatChanged;
                    }

                    if (mFlags & kFlagDequeueOutputPending) {
                        CHECK(handleDequeueOutputBuffer(mDequeueOutputReplyID));

                        ++mDequeueOutputTimeoutGeneration;
                        mFlags &= ~kFlagDequeueOutputPending;
                        mDequeueOutputReplyID = 0;
                    } else {
                        postActivityNotificationIfPossible();
                    }

                    break;
                }

                case ACodec::kWhatEOS:
                {
                    // We already notify the client of this by using the
                    // corresponding flag in "onOutputBufferReady".
                    break;
                }

                case ACodec::kWhatShutdownCompleted:
                {
                    if (mState == STOPPING) {
                        setState(INITIALIZED);
                    } else {
                        CHECK_EQ(mState, RELEASING);
                        setState(UNINITIALIZED);
                    }

                    (new AMessage)->postReply(mReplyID);
                    break;
                }

                case ACodec::kWhatFlushCompleted:
                {
                    CHECK_EQ(mState, FLUSHING);
                    setState(STARTED);

                    mCodec->signalResume();

                    (new AMessage)->postReply(mReplyID);
                    break;
                }

                default:
                    TRESPASS();
            }
            break;
        }

        case kWhatInit:
        {
            uint32_t replyID;
            CHECK(msg->senderAwaitsResponse(&replyID));

            if (mState != UNINITIALIZED) {
                sp<AMessage> response = new AMessage;
                response->setInt32("err", INVALID_OPERATION);

                response->postReply(replyID);
                break;
            }

            mReplyID = replyID;
            setState(INITIALIZING);

            AString name;
            CHECK(msg->findString("name", &name));

            int32_t nameIsType;
            int32_t encoder = false;
            CHECK(msg->findInt32("nameIsType", &nameIsType));
            if (nameIsType) {
                CHECK(msg->findInt32("encoder", &encoder));
            }

            sp<AMessage> format = new AMessage;

            if (nameIsType) {
                format->setString("mime", name.c_str());
                format->setInt32("encoder", encoder);
            } else {
                format->setString("componentName", name.c_str());
            }

            mCodec->initiateAllocateComponent(format);
            break;
        }

        case kWhatConfigure:
        {
            uint32_t replyID;
            CHECK(msg->senderAwaitsResponse(&replyID));

            if (mState != INITIALIZED) {
                sp<AMessage> response = new AMessage;
                response->setInt32("err", INVALID_OPERATION);

                response->postReply(replyID);
                break;
            }

            sp<RefBase> obj;
            if (!msg->findObject("native-window", &obj)) {
                obj.clear();
            }

            sp<AMessage> format;
            CHECK(msg->findMessage("format", &format));

            if (obj != NULL) {
                format->setObject("native-window", obj);

                status_t err = setNativeWindow(
                    static_cast<NativeWindowWrapper *>(obj.get())
                        ->getSurfaceTextureClient());

                if (err != OK) {
                    sp<AMessage> response = new AMessage;
                    response->setInt32("err", err);

                    response->postReply(replyID);
                    break;
                }
            } else {
                setNativeWindow(NULL);
            }

            mReplyID = replyID;
            setState(CONFIGURING);

            void *crypto;
            if (!msg->findPointer("crypto", &crypto)) {
                crypto = NULL;
            }

            mCrypto = static_cast<ICrypto *>(crypto);

            uint32_t flags;
            CHECK(msg->findInt32("flags", (int32_t *)&flags));

            if (flags & CONFIGURE_FLAG_ENCODE) {
                format->setInt32("encoder", true);
                mFlags |= kFlagIsEncoder;
            }

            extractCSD(format);

            mCodec->initiateConfigureComponent(format);
            break;
        }

        case kWhatCreateInputSurface:
        {
            uint32_t replyID;
            CHECK(msg->senderAwaitsResponse(&replyID));

            // Must be configured, but can't have been started yet.
            if (mState != CONFIGURED) {
                sp<AMessage> response = new AMessage;
                response->setInt32("err", INVALID_OPERATION);

                response->postReply(replyID);
                break;
            }

            mReplyID = replyID;
            mCodec->initiateCreateInputSurface();
            break;
        }

        case kWhatStart:
        {
            uint32_t replyID;
            CHECK(msg->senderAwaitsResponse(&replyID));

            if (mState != CONFIGURED) {
                sp<AMessage> response = new AMessage;
                response->setInt32("err", INVALID_OPERATION);

                response->postReply(replyID);
                break;
            }

            mReplyID = replyID;
            setState(STARTING);

            mCodec->initiateStart();
            break;
        }

        case kWhatStop:
        case kWhatRelease:
        {
            State targetState =
                (msg->what() == kWhatStop) ? INITIALIZED : UNINITIALIZED;

            uint32_t replyID;
            CHECK(msg->senderAwaitsResponse(&replyID));

            if (mState != INITIALIZED
                    && mState != CONFIGURED && mState != STARTED) {
                // We may be in "UNINITIALIZED" state already without the
                // client being aware of this if media server died while
                // we were being stopped. The client would assume that
                // after stop() returned, it would be safe to call release()
                // and it should be in this case, no harm to allow a release()
                // if we're already uninitialized.
                // Similarly stopping a stopped MediaCodec should be benign.
                sp<AMessage> response = new AMessage;
                response->setInt32(
                        "err",
                        mState == targetState ? OK : INVALID_OPERATION);

                response->postReply(replyID);
                break;
            }

            if (mFlags & kFlagSawMediaServerDie) {
                // It's dead, Jim. Don't expect initiateShutdown to yield
                // any useful results now...
                setState(UNINITIALIZED);
                (new AMessage)->postReply(replyID);
                break;
            }

            mReplyID = replyID;
            setState(msg->what() == kWhatStop ? STOPPING : RELEASING);

            mCodec->initiateShutdown(
                    msg->what() == kWhatStop /* keepComponentAllocated */);

            returnBuffersToCodec();
            break;
        }

        case kWhatDequeueInputBuffer:
        {
            uint32_t replyID;
            CHECK(msg->senderAwaitsResponse(&replyID));

            if (mHaveInputSurface) {
                ALOGE("dequeueInputBuffer can't be used with input surface");
                sp<AMessage> response = new AMessage;
                response->setInt32("err", INVALID_OPERATION);
                response->postReply(replyID);
                break;
            }

            if (handleDequeueInputBuffer(replyID, true /* new request */)) {
                break;
            }

            int64_t timeoutUs;
            CHECK(msg->findInt64("timeoutUs", &timeoutUs));

            if (timeoutUs == 0ll) {
                sp<AMessage> response = new AMessage;
                response->setInt32("err", -EAGAIN);
                response->postReply(replyID);
                break;
            }

            mFlags |= kFlagDequeueInputPending;
            mDequeueInputReplyID = replyID;

            if (timeoutUs > 0ll) {
                sp<AMessage> timeoutMsg =
                    new AMessage(kWhatDequeueInputTimedOut, id());
                timeoutMsg->setInt32(
                        "generation", ++mDequeueInputTimeoutGeneration);
                timeoutMsg->post(timeoutUs);
            }
            break;
        }

        case kWhatDequeueInputTimedOut:
        {
            int32_t generation;
            CHECK(msg->findInt32("generation", &generation));

            if (generation != mDequeueInputTimeoutGeneration) {
                // Obsolete
                break;
            }

            CHECK(mFlags & kFlagDequeueInputPending);

            sp<AMessage> response = new AMessage;
            response->setInt32("err", -EAGAIN);
            response->postReply(mDequeueInputReplyID);

            mFlags &= ~kFlagDequeueInputPending;
            mDequeueInputReplyID = 0;
            break;
        }

        case kWhatQueueInputBuffer:
        {
            uint32_t replyID;
            CHECK(msg->senderAwaitsResponse(&replyID));

            if (mState != STARTED || (mFlags & kFlagStickyError)) {
                sp<AMessage> response = new AMessage;
                response->setInt32("err", INVALID_OPERATION);

                response->postReply(replyID);
                break;
            }

            status_t err = onQueueInputBuffer(msg);

            sp<AMessage> response = new AMessage;
            response->setInt32("err", err);
            response->postReply(replyID);
            break;
        }

        case kWhatDequeueOutputBuffer:
        {
            uint32_t replyID;
            CHECK(msg->senderAwaitsResponse(&replyID));

            if (handleDequeueOutputBuffer(replyID, true /* new request */)) {
                break;
            }

            int64_t timeoutUs;
            CHECK(msg->findInt64("timeoutUs", &timeoutUs));

            if (timeoutUs == 0ll) {
                sp<AMessage> response = new AMessage;
                response->setInt32("err", -EAGAIN);
                response->postReply(replyID);
                break;
            }

            mFlags |= kFlagDequeueOutputPending;
            mDequeueOutputReplyID = replyID;

            if (timeoutUs > 0ll) {
                sp<AMessage> timeoutMsg =
                    new AMessage(kWhatDequeueOutputTimedOut, id());
                timeoutMsg->setInt32(
                        "generation", ++mDequeueOutputTimeoutGeneration);
                timeoutMsg->post(timeoutUs);
            }
            break;
        }

        case kWhatDequeueOutputTimedOut:
        {
            int32_t generation;
            CHECK(msg->findInt32("generation", &generation));

            if (generation != mDequeueOutputTimeoutGeneration) {
                // Obsolete
                break;
            }

            CHECK(mFlags & kFlagDequeueOutputPending);

            sp<AMessage> response = new AMessage;
            response->setInt32("err", -EAGAIN);
            response->postReply(mDequeueOutputReplyID);

            mFlags &= ~kFlagDequeueOutputPending;
            mDequeueOutputReplyID = 0;
            break;
        }

        case kWhatReleaseOutputBuffer:
        {
            uint32_t replyID;
            CHECK(msg->senderAwaitsResponse(&replyID));

            if (mState != STARTED || (mFlags & kFlagStickyError)) {
                sp<AMessage> response = new AMessage;
                response->setInt32("err", INVALID_OPERATION);

                response->postReply(replyID);
                break;
            }

            status_t err = onReleaseOutputBuffer(msg);

            sp<AMessage> response = new AMessage;
            response->setInt32("err", err);
            response->postReply(replyID);
            break;
        }

        case kWhatSignalEndOfInputStream:
        {
            uint32_t replyID;
            CHECK(msg->senderAwaitsResponse(&replyID));

            if (mState != STARTED || (mFlags & kFlagStickyError)) {
                sp<AMessage> response = new AMessage;
                response->setInt32("err", INVALID_OPERATION);

                response->postReply(replyID);
                break;
            }

            mReplyID = replyID;
            mCodec->signalEndOfInputStream();
            break;
        }

        case kWhatGetBuffers:
        {
            uint32_t replyID;
            CHECK(msg->senderAwaitsResponse(&replyID));

            if (mState != STARTED || (mFlags & kFlagStickyError)) {
                sp<AMessage> response = new AMessage;
                response->setInt32("err", INVALID_OPERATION);

                response->postReply(replyID);
                break;
            }

            int32_t portIndex;
            CHECK(msg->findInt32("portIndex", &portIndex));

            Vector<sp<ABuffer> > *dstBuffers;
            CHECK(msg->findPointer("buffers", (void **)&dstBuffers));

            dstBuffers->clear();
            const Vector<BufferInfo> &srcBuffers = mPortBuffers[portIndex];

            for (size_t i = 0; i < srcBuffers.size(); ++i) {
                const BufferInfo &info = srcBuffers.itemAt(i);

                dstBuffers->push_back(
                        (portIndex == kPortIndexInput && mCrypto != NULL)
                                ? info.mEncryptedData : info.mData);
            }

            (new AMessage)->postReply(replyID);
            break;
        }

        case kWhatFlush:
        {
            uint32_t replyID;
            CHECK(msg->senderAwaitsResponse(&replyID));

            if (mState != STARTED || (mFlags & kFlagStickyError)) {
                sp<AMessage> response = new AMessage;
                response->setInt32("err", INVALID_OPERATION);

                response->postReply(replyID);
                break;
            }

            mReplyID = replyID;
            setState(FLUSHING);

            mCodec->signalFlush();
            returnBuffersToCodec();
            break;
        }

        case kWhatGetOutputFormat:
        {
            uint32_t replyID;
            CHECK(msg->senderAwaitsResponse(&replyID));

            if ((mState != STARTED && mState != FLUSHING)
                    || (mFlags & kFlagStickyError)
                    || mOutputFormat == NULL) {
                sp<AMessage> response = new AMessage;
                response->setInt32("err", INVALID_OPERATION);

                response->postReply(replyID);
                break;
            }

            sp<AMessage> response = new AMessage;
            response->setMessage("format", mOutputFormat);
            response->postReply(replyID);
            break;
        }

        case kWhatRequestIDRFrame:
        {
            mCodec->signalRequestIDRFrame();
            break;
        }

        case kWhatRequestActivityNotification:
        {
            CHECK(mActivityNotify == NULL);
            CHECK(msg->findMessage("notify", &mActivityNotify));

            postActivityNotificationIfPossible();
            break;
        }

        case kWhatGetName:
        {
            uint32_t replyID;
            CHECK(msg->senderAwaitsResponse(&replyID));

            if (mComponentName.empty()) {
                sp<AMessage> response = new AMessage;
                response->setInt32("err", INVALID_OPERATION);

                response->postReply(replyID);
                break;
            }

            sp<AMessage> response = new AMessage;
            response->setString("name", mComponentName.c_str());
            response->postReply(replyID);
            break;
        }

        case kWhatSetParameters:
        {
            uint32_t replyID;
            CHECK(msg->senderAwaitsResponse(&replyID));

            sp<AMessage> params;
            CHECK(msg->findMessage("params", &params));

            status_t err = onSetParameters(params);

            sp<AMessage> response = new AMessage;
            response->setInt32("err", err);

            response->postReply(replyID);
            break;
        }

        default:
            TRESPASS();
    }
}

void MediaCodec::extractCSD(const sp<AMessage> &format) {
    mCSD.clear();

    size_t i = 0;
    for (;;) {
        sp<ABuffer> csd;
        if (!format->findBuffer(StringPrintf("csd-%u", i).c_str(), &csd)) {
            break;
        }

        mCSD.push_back(csd);
        ++i;
    }

    ALOGV("Found %u pieces of codec specific data.", mCSD.size());
}

status_t MediaCodec::queueCSDInputBuffer(size_t bufferIndex) {
    CHECK(!mCSD.empty());

    BufferInfo *info =
        &mPortBuffers[kPortIndexInput].editItemAt(bufferIndex);

    sp<ABuffer> csd = *mCSD.begin();
    mCSD.erase(mCSD.begin());

    const sp<ABuffer> &codecInputData =
        (mCrypto != NULL) ? info->mEncryptedData : info->mData;

    if (csd->size() > codecInputData->capacity()) {
        return -EINVAL;
    }

    memcpy(codecInputData->data(), csd->data(), csd->size());

    AString errorDetailMsg;

    sp<AMessage> msg = new AMessage(kWhatQueueInputBuffer, id());
    msg->setSize("index", bufferIndex);
    msg->setSize("offset", 0);
    msg->setSize("size", csd->size());
    msg->setInt64("timeUs", 0ll);
    msg->setInt32("flags", BUFFER_FLAG_CODECCONFIG);
    msg->setPointer("errorDetailMsg", &errorDetailMsg);

    return onQueueInputBuffer(msg);
}

void MediaCodec::setState(State newState) {
    if (newState == INITIALIZED || newState == UNINITIALIZED) {
        delete mSoftRenderer;
        mSoftRenderer = NULL;

        mCrypto.clear();
        setNativeWindow(NULL);

        mOutputFormat.clear();
        mFlags &= ~kFlagOutputFormatChanged;
        mFlags &= ~kFlagOutputBuffersChanged;
        mFlags &= ~kFlagStickyError;
        mFlags &= ~kFlagIsEncoder;
        mFlags &= ~kFlagGatherCodecSpecificData;

        mActivityNotify.clear();
    }

    if (newState == UNINITIALIZED) {
        mComponentName.clear();

        // The component is gone, mediaserver's probably back up already
        // but should definitely be back up should we try to instantiate
        // another component.. and the cycle continues.
        mFlags &= ~kFlagSawMediaServerDie;
    }

    mState = newState;

    cancelPendingDequeueOperations();
}

void MediaCodec::returnBuffersToCodec() {
    returnBuffersToCodecOnPort(kPortIndexInput);
    returnBuffersToCodecOnPort(kPortIndexOutput);
}

void MediaCodec::returnBuffersToCodecOnPort(int32_t portIndex) {
    CHECK(portIndex == kPortIndexInput || portIndex == kPortIndexOutput);

    Vector<BufferInfo> *buffers = &mPortBuffers[portIndex];

    for (size_t i = 0; i < buffers->size(); ++i) {
        BufferInfo *info = &buffers->editItemAt(i);

        if (info->mNotify != NULL) {
            sp<AMessage> msg = info->mNotify;
            info->mNotify = NULL;
            info->mOwnedByClient = false;

            if (portIndex == kPortIndexInput) {
                /* no error, just returning buffers */
                msg->setInt32("err", OK);
            }
            msg->post();
        }
    }

    mAvailPortBuffers[portIndex].clear();
}

size_t MediaCodec::updateBuffers(
        int32_t portIndex, const sp<AMessage> &msg) {
    CHECK(portIndex == kPortIndexInput || portIndex == kPortIndexOutput);

    void *bufferID;
    CHECK(msg->findPointer("buffer-id", &bufferID));

    Vector<BufferInfo> *buffers = &mPortBuffers[portIndex];

    for (size_t i = 0; i < buffers->size(); ++i) {
        BufferInfo *info = &buffers->editItemAt(i);

        if (info->mBufferID == bufferID) {
            CHECK(info->mNotify == NULL);
            CHECK(msg->findMessage("reply", &info->mNotify));

            mAvailPortBuffers[portIndex].push_back(i);

            return i;
        }
    }

    TRESPASS();

    return 0;
}

status_t MediaCodec::onQueueInputBuffer(const sp<AMessage> &msg) {
    size_t index;
    size_t offset;
    size_t size;
    int64_t timeUs;
    uint32_t flags;
    CHECK(msg->findSize("index", &index));
    CHECK(msg->findSize("offset", &offset));
    CHECK(msg->findInt64("timeUs", &timeUs));
    CHECK(msg->findInt32("flags", (int32_t *)&flags));

    const CryptoPlugin::SubSample *subSamples;
    size_t numSubSamples;
    const uint8_t *key;
    const uint8_t *iv;
    CryptoPlugin::Mode mode = CryptoPlugin::kMode_Unencrypted;

    // We allow the simpler queueInputBuffer API to be used even in
    // secure mode, by fabricating a single unencrypted subSample.
    CryptoPlugin::SubSample ss;

    if (msg->findSize("size", &size)) {
        if (mCrypto != NULL) {
            ss.mNumBytesOfClearData = size;
            ss.mNumBytesOfEncryptedData = 0;

            subSamples = &ss;
            numSubSamples = 1;
            key = NULL;
            iv = NULL;
        }
    } else {
        if (mCrypto == NULL) {
            return -EINVAL;
        }

        CHECK(msg->findPointer("subSamples", (void **)&subSamples));
        CHECK(msg->findSize("numSubSamples", &numSubSamples));
        CHECK(msg->findPointer("key", (void **)&key));
        CHECK(msg->findPointer("iv", (void **)&iv));

        int32_t tmp;
        CHECK(msg->findInt32("mode", &tmp));

        mode = (CryptoPlugin::Mode)tmp;

        size = 0;
        for (size_t i = 0; i < numSubSamples; ++i) {
            size += subSamples[i].mNumBytesOfClearData;
            size += subSamples[i].mNumBytesOfEncryptedData;
        }
    }

    if (index >= mPortBuffers[kPortIndexInput].size()) {
        return -ERANGE;
    }

    BufferInfo *info = &mPortBuffers[kPortIndexInput].editItemAt(index);

    if (info->mNotify == NULL || !info->mOwnedByClient) {
        return -EACCES;
    }

    if (offset + size > info->mData->capacity()) {
        return -EINVAL;
    }

    sp<AMessage> reply = info->mNotify;
    info->mData->setRange(offset, size);
    info->mData->meta()->setInt64("timeUs", timeUs);

    if (flags & BUFFER_FLAG_EOS) {
        info->mData->meta()->setInt32("eos", true);
    }

    if (flags & BUFFER_FLAG_CODECCONFIG) {
        info->mData->meta()->setInt32("csd", true);
    }

    if (mCrypto != NULL) {
        if (size > info->mEncryptedData->capacity()) {
            return -ERANGE;
        }

        AString *errorDetailMsg;
        CHECK(msg->findPointer("errorDetailMsg", (void **)&errorDetailMsg));

        ssize_t result = mCrypto->decrypt(
                (mFlags & kFlagIsSecure) != 0,
                key,
                iv,
                mode,
                info->mEncryptedData->base() + offset,
                subSamples,
                numSubSamples,
                info->mData->base(),
                errorDetailMsg);

        if (result < 0) {
            return result;
        }

        info->mData->setRange(0, result);
    }

    reply->setBuffer("buffer", info->mData);
    reply->post();

    info->mNotify = NULL;
    info->mOwnedByClient = false;

    return OK;
}

status_t MediaCodec::onReleaseOutputBuffer(const sp<AMessage> &msg) {
    size_t index;
    CHECK(msg->findSize("index", &index));

    int32_t render;
    if (!msg->findInt32("render", &render)) {
        render = 0;
    }

    if (mState != STARTED) {
        return -EINVAL;
    }

    if (index >= mPortBuffers[kPortIndexOutput].size()) {
        return -ERANGE;
    }

    BufferInfo *info = &mPortBuffers[kPortIndexOutput].editItemAt(index);

    if (info->mNotify == NULL || !info->mOwnedByClient) {
        return -EACCES;
    }

    if (render && (info->mData == NULL || info->mData->size() != 0)) {
        info->mNotify->setInt32("render", true);

        if (mSoftRenderer != NULL) {
            mSoftRenderer->render(
                    info->mData->data(), info->mData->size(), NULL);
        }
    }

    info->mNotify->post();
    info->mNotify = NULL;
    info->mOwnedByClient = false;

    return OK;
}

ssize_t MediaCodec::dequeuePortBuffer(int32_t portIndex) {
    CHECK(portIndex == kPortIndexInput || portIndex == kPortIndexOutput);

    List<size_t> *availBuffers = &mAvailPortBuffers[portIndex];

    if (availBuffers->empty()) {
        return -EAGAIN;
    }

    size_t index = *availBuffers->begin();
    availBuffers->erase(availBuffers->begin());

    BufferInfo *info = &mPortBuffers[portIndex].editItemAt(index);
    CHECK(!info->mOwnedByClient);
    info->mOwnedByClient = true;

    return index;
}

status_t MediaCodec::setNativeWindow(
        const sp<Surface> &surfaceTextureClient) {
    status_t err;

    if (mNativeWindow != NULL) {
        err = native_window_api_disconnect(
                mNativeWindow.get(), NATIVE_WINDOW_API_MEDIA);

        if (err != OK) {
            ALOGW("native_window_api_disconnect returned an error: %s (%d)",
                    strerror(-err), err);
        }

        mNativeWindow.clear();
    }

    if (surfaceTextureClient != NULL) {
        err = native_window_api_connect(
                surfaceTextureClient.get(), NATIVE_WINDOW_API_MEDIA);

        if (err != OK) {
            ALOGE("native_window_api_connect returned an error: %s (%d)",
                    strerror(-err), err);

            return err;
        }

        mNativeWindow = surfaceTextureClient;
    }

    return OK;
}

void MediaCodec::postActivityNotificationIfPossible() {
    if (mActivityNotify == NULL) {
        return;
    }

    if ((mFlags & (kFlagStickyError
                    | kFlagOutputBuffersChanged
                    | kFlagOutputFormatChanged))
            || !mAvailPortBuffers[kPortIndexInput].empty()
            || !mAvailPortBuffers[kPortIndexOutput].empty()) {
        mActivityNotify->post();
        mActivityNotify.clear();
    }
}

status_t MediaCodec::setParameters(const sp<AMessage> &params) {
    sp<AMessage> msg = new AMessage(kWhatSetParameters, id());
    msg->setMessage("params", params);

    sp<AMessage> response;
    return PostAndAwaitResponse(msg, &response);
}

status_t MediaCodec::onSetParameters(const sp<AMessage> &params) {
    mCodec->signalSetParameters(params);

    return OK;
}

status_t MediaCodec::amendOutputFormatWithCodecSpecificData(
        const sp<ABuffer> &buffer) {
    AString mime;
    CHECK(mOutputFormat->findString("mime", &mime));

    if (!strcasecmp(mime.c_str(), MEDIA_MIMETYPE_VIDEO_AVC)) {
        // Codec specific data should be SPS and PPS in a single buffer,
        // each prefixed by a startcode (0x00 0x00 0x00 0x01).
        // We separate the two and put them into the output format
        // under the keys "csd-0" and "csd-1".

        unsigned csdIndex = 0;

        const uint8_t *data = buffer->data();
        size_t size = buffer->size();

        const uint8_t *nalStart;
        size_t nalSize;
        while (getNextNALUnit(&data, &size, &nalStart, &nalSize, true) == OK) {
            sp<ABuffer> csd = new ABuffer(nalSize + 4);
            memcpy(csd->data(), "\x00\x00\x00\x01", 4);
            memcpy(csd->data() + 4, nalStart, nalSize);

            mOutputFormat->setBuffer(
                    StringPrintf("csd-%u", csdIndex).c_str(), csd);

            ++csdIndex;
        }

        if (csdIndex != 2) {
            return ERROR_MALFORMED;
        }
    } else {
        // For everything else we just stash the codec specific data into
        // the output format as a single piece of csd under "csd-0".
        mOutputFormat->setBuffer("csd-0", buffer);
    }

    return OK;
}

}  // namespace android