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/*
* This File is part of Davix, The IO library for HTTP based protocols
* Copyright (C) CERN 2019
* Author: Georgios Bitzes <georgios.bitzes@cern.ch>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#include "ConnectionInitiator.hpp"
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <unistd.h>
#include <fcntl.h>
#include <sstream>
#define SSTR(message) static_cast<std::ostringstream&>(std::ostringstream().flush() << message).str()
inline std::string q(const std::string &str) {
return SSTR("'" << str << "'");
}
ConnectionInitiator::ConnectionInitiator(const std::string &hostname, int port) {
fd = -1;
localerrno = 0;
struct addrinfo hints, *servinfo, *p;
int rv;
memset(&hints, 0, sizeof hints);
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
hints.ai_flags = AI_CANONNAME;
if ((rv = getaddrinfo(hostname.c_str(), SSTR(port).c_str(),
&hints, &servinfo)) != 0) {
localerrno = rv;
error = SSTR("error when resolving " << q(hostname) << ": " << gai_strerror(rv));
return;
}
// loop through all the results and connect to the first we can
for (p = servinfo; p != NULL; p = p->ai_next) {
if ((fd = socket(p->ai_family, p->ai_socktype, p->ai_protocol)) == -1) {
continue;
}
if (::connect(fd, p->ai_addr, p->ai_addrlen) == -1) {
localerrno = errno;
close(fd);
fd = -1;
continue;
}
break;
}
freeaddrinfo(servinfo);
if (p == NULL) {
error = SSTR("Unable to connect to " << q(hostname) << ":" << port);
fd = -1;
return;
}
// clear any transient errors which might have occurred while trying to connect
localerrno = 0;
// make socket non-blocking
rv = fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_NONBLOCK);
if(rv != 0) {
localerrno = errno;
error = SSTR("Unable to make socket non-blocking");
fd = -1;
}
}
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