libcruft-util/posix/socket.cpp

124 lines
3.3 KiB
C++

/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* Copyright 2017 Danny Robson <danny@nerdcruft.net>
*/
#include "socket.hpp"
#include "except.hpp"
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
using util::posix::socket;
///////////////////////////////////////////////////////////////////////////////
class lookup {
public:
lookup (const util::view<const char*> host, int port):
m_addresses (nullptr, freeaddrinfo)
{
struct ::addrinfo hints {};
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
const struct {
std::string host;
std::string port;
} strings {
.host = std::string (std::begin (host), std::end (host)),
.port = std::to_string (port)
};
addrinfo* _addresses;
util::posix::eai::try_code (
getaddrinfo (
strings.host.c_str (),
strings.port.c_str (),
&hints,
&_addresses
)
);
m_addresses.reset (_addresses);
};
auto begin (void) const { return m_addresses.get (); }
auto end (void) const { return nullptr; }
private:
std::unique_ptr<addrinfo[],void(*)(addrinfo*)> m_addresses;
};
///////////////////////////////////////////////////////////////////////////////
static util::posix::fd
connect_host (const util::view<const char*> host, int port)
{
for (const auto &info: lookup { host, port }) {
util::posix::fd sock {
socket (info.ai_family, info.ai_socktype, info.ai_protocol)
};
if (sock == -1)
continue;
if (connect (sock, info.ai_addr, info.ai_addrlen))
continue;
return sock;
}
throw std::runtime_error ("unable to connect");
}
///////////////////////////////////////////////////////////////////////////////
socket::socket (int domain, int type):
socket (domain, type, 0)
{ ; }
//-----------------------------------------------------------------------------
socket::socket (int domain, int type, int protocol):
fd (::socket (domain, type, protocol))
{ ; }
//-----------------------------------------------------------------------------
socket::socket (util::view<const char*> host, int port):
fd (connect_host (host, port))
{ ; }
//-----------------------------------------------------------------------------
socket::~socket ()
{ ; }
///////////////////////////////////////////////////////////////////////////////
void
socket::connect (util::view<const char*> host, int port)
{
for (const auto &info: lookup { host, port }) {
if (!::connect (*this, info.ai_addr, info.ai_addrlen))
return;
}
throw std::runtime_error ("unable to reconnect");
}