snapcast/server/streamreader/process_stream.hpp

86 lines
2.9 KiB
C++

/***
This file is part of snapcast
Copyright (C) 2014-2025 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/>.
***/
#pragma once
// local headers
#include "asio_stream.hpp"
#include "watchdog.hpp"
// 3rd party headers
// standard headers
#include <memory>
#include <string>
namespace bp = boost::process;
namespace streamreader
{
using boost::asio::posix::stream_descriptor;
/// Starts an external process and reads and PCM data from stdout
/**
* Starts an external process, reads PCM data from stdout, and passes the data to an encoder.
* Implements EncoderListener to get the encoded data.
* Data is passed to the PcmStream::Listener
*/
class ProcessStream : public AsioStream<stream_descriptor>
{
public:
/// c'tor. Encoded PCM data is passed to the PipeListener
ProcessStream(PcmStream::Listener* pcmListener, boost::asio::io_context& ioc, const ServerSettings& server_settings, const StreamUri& uri);
/// d'tor
~ProcessStream() override = default;
protected:
void connect() override;
void disconnect() override;
std::string exe_; ///< filename of the process
std::string path_; ///< base path of the provess
std::string params_; ///< parameters for the process
bp::pipe pipe_stdout_; ///< stdout of the process
bp::pipe pipe_stderr_; ///< stderr of the process
bp::child process_; ///< the process
bool logStderr_; ///< log stderr to log?
boost::asio::streambuf streambuf_stderr_; ///< stderr read buffer
std::unique_ptr<stream_descriptor> stream_stderr_; ///< stderr stream
/// Read async from stderr
virtual void stderrReadLine();
/// Called for a line read from stderr
virtual void onStderrMsg(const std::string& line);
/// Try to find exe and base path, throw on error
virtual void initExeAndPath(const std::string& filename);
/// @return the executables complete path to @p filename
std::string findExe(const std::string& filename) const;
size_t wd_timeout_sec_; ///< Watchdog timeout for arrival of new log lines
std::unique_ptr<Watchdog> watchdog_; ///< the watchdog
/// called on wd timeout, kills the process
void onTimeout(std::chrono::milliseconds ms);
};
} // namespace streamreader