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#include <network/socket_handler.hpp>
#include <utils/scopeguard.hpp>
#include <network/poller.hpp>
#include <logger/logger.hpp>
#include <sys/socket.h>
#include <sys/types.h>
#include <stdexcept>
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include <cstring>
#include <fcntl.h>
#include <netdb.h>
#include <stdio.h>
#include <iostream>
SocketHandler::SocketHandler():
poller(nullptr),
connected(false),
connecting(false)
{
this->init_socket();
}
void SocketHandler::init_socket()
{
if ((this->socket = ::socket(AF_INET, SOCK_STREAM, 0)) == -1)
throw std::runtime_error("Could not create socket");
int optval = 1;
if (::setsockopt(this->socket, SOL_SOCKET, SO_KEEPALIVE, &optval, sizeof(optval)) == -1)
log_warning("Failed to enable TCP keepalive on socket: " << strerror(errno));
// Set the socket on non-blocking mode. This is useful to receive a EAGAIN
// error when connect() would block, to not block the whole process if a
// remote is not responsive.
const int existing_flags = ::fcntl(this->socket, F_GETFL, 0);
if ((existing_flags == -1) ||
(::fcntl(this->socket, F_SETFL, existing_flags | O_NONBLOCK) == -1))
throw std::runtime_error(std::string("Could not initialize socket: ") + strerror(errno));
}
void SocketHandler::connect(const std::string& address, const std::string& port)
{
this->address = address;
this->port = port;
utils::ScopeGuard sg;
struct addrinfo* addr_res;
if (!this->connecting)
{
log_info("Trying to connect to " << address << ":" << port);
// Get the addrinfo from getaddrinfo, only if this is the first call
// of this function.
struct addrinfo hints;
memset(&hints, 0, sizeof(struct addrinfo));
hints.ai_flags = 0;
hints.ai_family = AF_INET;
hints.ai_socktype = SOCK_STREAM;
hints.ai_protocol = 0;
const int res = ::getaddrinfo(address.c_str(), port.c_str(), &hints, &addr_res);
if (res != 0)
{
log_warning(std::string("getaddrinfo failed: ") + gai_strerror(res));
this->close();
this->on_connection_failed(gai_strerror(res));
return ;
}
// Make sure the alloced structure is always freed at the end of the
// function
sg.add_callback([&addr_res](){ freeaddrinfo(addr_res); });
}
else
{
// This function is called again, use the saved addrinfo structure,
// instead of re-doing the whole getaddrinfo process. We insert only
// the meaningful values in the structure, and indicate that these are
// the only possible values with ai_next = NULL.
addr_res = (struct addrinfo*)malloc(sizeof(struct addrinfo));
if (!addr_res)
{
this->close();
this->on_connection_failed("memory error");
return ;
}
sg.add_callback([&addr_res](){ free(addr_res); });
addr_res->ai_next = NULL;
addr_res->ai_addr = &this->ai_addr;
addr_res->ai_addrlen = this->ai_addrlen;
}
this->connecting = true;
for (struct addrinfo* rp = addr_res; rp; rp = rp->ai_next)
{
if (::connect(this->socket, rp->ai_addr, rp->ai_addrlen) == 0)
{
log_info("Connection success.");
this->connected = true;
this->connecting = false;
this->on_connected();
return ;
}
else if (errno == EINPROGRESS || errno == EALREADY)
{ // retry this process later, when the socket
// is ready to be written on.
log_debug("Need to retry connecting later..." << strerror(errno));
this->poller->watch_send_events(this);
// Save the addrinfo structure, to use it on the next call
this->ai_addrlen = rp->ai_addrlen;
memcpy(&this->ai_addr, rp->ai_addr, this->ai_addrlen);
return ;
}
log_info("Connection failed:" << strerror(errno));
}
log_error("All connection attempts failed.");
this->close();
this->on_connection_failed(strerror(errno));
return ;
}
void SocketHandler::connect()
{
this->connect(this->address, this->port);
}
void SocketHandler::set_poller(Poller* poller)
{
this->poller = poller;
}
void SocketHandler::on_recv(const size_t nb)
{
char buf[4096];
ssize_t size = ::recv(this->socket, buf, nb, 0);
if (0 == size)
{
this->on_connection_close();
this->close();
}
else if (-1 == static_cast<ssize_t>(size))
{
log_warning("Error while reading from socket: " << strerror(errno));
this->on_connection_close();
this->close();
}
else
{
this->in_buf += std::string(buf, size);
this->parse_in_buffer();
}
}
void SocketHandler::on_send()
{
const ssize_t res = ::send(this->socket, this->out_buf.data(), this->out_buf.size(), MSG_NOSIGNAL);
if (res == -1)
{
log_error("send failed: " << strerror(errno));
this->on_connection_close();
this->close();
}
else
{
this->out_buf = this->out_buf.substr(res, std::string::npos);
if (this->out_buf.empty())
this->poller->stop_watching_send_events(this);
}
}
void SocketHandler::close()
{
this->connected = false;
this->connecting = false;
this->poller->remove_socket_handler(this->get_socket());
::close(this->socket);
// recreate the socket for a potential future usage
this->init_socket();
}
socket_t SocketHandler::get_socket() const
{
return this->socket;
}
void SocketHandler::send_data(std::string&& data)
{
this->out_buf += std::move(data);
if (!this->out_buf.empty())
{
this->poller->watch_send_events(this);
}
}
bool SocketHandler::is_connected() const
{
return this->connected;
}
bool SocketHandler::is_connecting() const
{
return this->connecting;
}
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