posix/socket: add a convenience wrapper for sockets

This commit is contained in:
Danny Robson 2017-12-22 18:38:30 +11:00
parent cb9e9afcd3
commit ce64396da4
3 changed files with 185 additions and 0 deletions

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@ -84,6 +84,8 @@ list (
posix/except.hpp posix/except.hpp
posix/fd.cpp posix/fd.cpp
posix/fd.hpp posix/fd.hpp
posix/socket.cpp
posix/socket.hpp
) )

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posix/socket.cpp Normal file
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@ -0,0 +1,123 @@
/*
* 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");
}

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posix/socket.hpp Normal file
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/*
* 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>
*/
#ifndef CRUFT_UTIL_POSIX_SOCKET_HPP
#define CRUFT_UTIL_POSIX_SOCKET_HPP
#include "fd.hpp"
#include "except.hpp"
#include <sys/types.h>
#include <sys/socket.h>
namespace util::posix {
class socket : public fd {
public:
socket (int domain, int type);
socket (int domain, int type, int protocol);
socket (util::view<const char*> host, int port);
void connect (util::view<const char*> host, int port);
// the destructor is provided so that we can operate more cleanly on
// win32 where we must call closesocket instead of the normal close.
// because windows...
~socket ();
void shutdown ();
template <typename ValueT>
void setoption (int _level, int _name, const ValueT &_value)
{
error::try_code (
setsockopt (
native (),
_level,
_name,
&_value, sizeof (_value)
)
);
}
};
};
#endif