snapcast/server/streamreader/pcm_stream.cpp

/***
    This file is part of snapcast
    Copyright (C) 2014-2019  Johannes Pohl

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
***/

#include <fcntl.h>
#include <memory>
#include <sys/stat.h>

#include "common/aixlog.hpp"
#include "common/snap_exception.hpp"
#include "common/str_compat.hpp"
#include "encoder/encoder_factory.hpp"
#include "pcm_stream.hpp"


using namespace std;



PcmStream::PcmStream(PcmListener* pcmListener, boost::asio::io_context& ioc, const StreamUri& uri)
    : active_(false), pcmListener_(pcmListener), uri_(uri), pcmReadMs_(20), state_(ReaderState::kIdle), ioc_(ioc)
{
    encoder::EncoderFactory encoderFactory;
    if (uri_.query.find("codec") == uri_.query.end())
        throw SnapException("Stream URI must have a codec");
    encoder_.reset(encoderFactory.createEncoder(uri_.query["codec"]));

    if (uri_.query.find("name") == uri_.query.end())
        throw SnapException("Stream URI must have a name");
    name_ = uri_.query["name"];

    if (uri_.query.find("sampleformat") == uri_.query.end())
        throw SnapException("Stream URI must have a sampleformat");
    sampleFormat_ = SampleFormat(uri_.query["sampleformat"]);
    LOG(INFO) << "PcmStream sampleFormat: " << sampleFormat_.getFormat() << "\n";

    if (uri_.query.find("buffer_ms") != uri_.query.end())
        pcmReadMs_ = cpt::stoul(uri_.query["buffer_ms"]);

    // meta_.reset(new msg::StreamTags());
    // meta_->msg["stream"] = name_;
    setMeta(json());
}


PcmStream::~PcmStream()
{
    stop();
}


std::shared_ptr<msg::CodecHeader> PcmStream::getHeader()
{
    return encoder_->getHeader();
}


const StreamUri& PcmStream::getUri() const
{
    return uri_;
}


const std::string& PcmStream::getName() const
{
    return name_;
}


const std::string& PcmStream::getId() const
{
    return getName();
}


const SampleFormat& PcmStream::getSampleFormat() const
{
    return sampleFormat_;
}


void PcmStream::start()
{
    LOG(DEBUG) << "PcmStream start: " << sampleFormat_.getFormat() << "\n";
    encoder_->init(this, sampleFormat_);
    active_ = true;
    thread_ = thread(&PcmStream::worker, this);
}


void PcmStream::stop()
{
    if (!active_ && !thread_.joinable())
        return;

    active_ = false;
    cv_.notify_one();
    if (thread_.joinable())
        thread_.join();
}


bool PcmStream::sleep(int32_t ms)
{
    if (ms < 0)
        return true;
    std::unique_lock<std::mutex> lck(mtx_);
    return (!cv_.wait_for(lck, std::chrono::milliseconds(ms), [this] { return !active_; }));
}


ReaderState PcmStream::getState() const
{
    return state_;
}


void PcmStream::setState(const ReaderState& newState)
{
    if (newState != state_)
    {
        LOG(DEBUG) << "State changed: " << static_cast<int>(state_) << " => " << static_cast<int>(newState) << "\n";
        state_ = newState;
        if (pcmListener_)
            pcmListener_->onStateChanged(this, newState);
    }
}


void PcmStream::onChunkEncoded(const encoder::Encoder* /*encoder*/, msg::PcmChunk* chunk, double duration)
{
    //	LOG(INFO) << "onChunkEncoded: " << duration << " us\n";
    if (duration <= 0)
        return;

    chunk->timestamp.sec = tvEncodedChunk_.tv_sec;
    chunk->timestamp.usec = tvEncodedChunk_.tv_usec;
    chronos::addUs(tvEncodedChunk_, duration * 1000);
    if (pcmListener_)
        pcmListener_->onChunkRead(this, chunk, duration);
}


json PcmStream::toJson() const
{
    string state("unknown");
    if (state_ == ReaderState::kIdle)
        state = "idle";
    else if (state_ == ReaderState::kPlaying)
        state = "playing";
    else if (state_ == ReaderState::kDisabled)
        state = "disabled";

    json j = {
        {"uri", uri_.toJson()}, {"id", getId()}, {"status", state},
    };

    if (meta_)
        j["meta"] = meta_->msg;

    return j;
}

std::shared_ptr<msg::StreamTags> PcmStream::getMeta() const
{
    return meta_;
}

void PcmStream::setMeta(const json& jtag)
{
    meta_.reset(new msg::StreamTags(jtag));
    meta_->msg["STREAM"] = name_;
    LOG(INFO) << "metadata=" << meta_->msg.dump(4) << "\n";

    // Trigger a stream update
    if (pcmListener_)
        pcmListener_->onMetaChanged(this);
}