blob: bddc08e38d5953bc40991ebed0f2f0deff7871e7 [file] [log] [blame]
// SPDX-License-Identifier: Apache-2.0
// Copyright (C) 2020 YADRO
#include "host_console.hpp"
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <unistd.h>
#include <cstring>
#include <system_error>
/**
* @brief Base path to the console's socket.
* See obmc-console for details.
*/
static constexpr char socketPath[] = "\0obmc-console";
HostConsole::HostConsole(const std::string& socketId) :
socketId(socketId), socketFd(-1)
{}
HostConsole::~HostConsole()
{
if (socketFd != -1)
{
close(socketFd);
}
}
void HostConsole::connect()
{
if (socketFd != -1)
{
throw std::runtime_error("Socket already opened");
}
// Create socket
socketFd = socket(AF_UNIX, SOCK_STREAM, 0);
if (socketFd == -1)
{
std::error_code ec(errno ? errno : EIO, std::generic_category());
throw std::system_error(ec, "Unable to create socket");
}
// Set non-blocking mode for socket
int opt = 1;
if (ioctl(socketFd, FIONBIO, &opt))
{
std::error_code ec(errno ? errno : EIO, std::generic_category());
throw std::system_error(ec, "Unable to set non-blocking mode");
}
// Construct path to the socket file (see obmc-console for details)
std::string path(socketPath, socketPath + sizeof(socketPath) - 1);
if (!socketId.empty())
{
path += '.';
path += socketId;
}
if (path.length() > sizeof(sockaddr_un::sun_path))
{
throw std::invalid_argument("Invalid socket ID");
}
sockaddr_un sa;
sa.sun_family = AF_UNIX;
memcpy(&sa.sun_path, path.c_str(), path.length());
// Connect to host's log stream via socket.
// The owner of the socket (server) is obmc-console service and
// we have a dependency on it written in the systemd unit file, but
// we can't guarantee that the socket is initialized at the moment.
size_t connectAttempts = 60; // Number of attempts
const socklen_t len = sizeof(sa) - sizeof(sa.sun_path) + path.length();
int rc = -1;
while (connectAttempts--)
{
rc = ::connect(socketFd, reinterpret_cast<const sockaddr*>(&sa), len);
if (!rc)
{
break;
}
else
{
sleep(1); // Make 1 second pause between attempts
}
}
if (rc)
{
std::string err = "Unable to connect to console";
if (!socketId.empty())
{
err += ' ';
err += socketId;
}
std::error_code ec(errno ? errno : EIO, std::generic_category());
throw std::system_error(ec, err);
}
}
size_t HostConsole::read(char* buf, size_t sz) const
{
ssize_t rsz = ::read(socketFd, buf, sz);
if (rsz < 0)
{
if (errno == EAGAIN || errno == EWOULDBLOCK)
{
// We are in non-blocking mode, so ignore these codes
rsz = 0;
}
else
{
std::string err = "Unable to read socket";
if (!socketId.empty())
{
err += ' ';
err += socketId;
}
std::error_code ec(errno ? errno : EIO, std::generic_category());
throw std::system_error(ec, err);
}
}
return static_cast<size_t>(rsz);
}
HostConsole::operator int() const
{
return socketFd;
}