gcc/libcody/netclient.cc

142 lines
2.7 KiB
C++

// CODYlib -*- mode:c++ -*-
// Copyright (C) 2020 Nathan Sidwell, nathan@acm.org
// License: Apache v2.0
// Cody
#include "internal.hh"
#if CODY_NETWORKING
// C
#include <cerrno>
#include <cstring>
// OS
#include <netdb.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <sys/un.h>
#ifndef AI_NUMERICSERV
#define AI_NUMERICSERV 0
#endif
// Client-side networking helpers
namespace Cody {
int OpenSocket (char const **e, sockaddr const *addr, socklen_t len)
{
char const *errstr = nullptr;
int fd = socket (addr->sa_family, SOCK_STREAM, 0);
if (fd < 0)
{
errstr = "creating socket";
fail:;
int err = errno;
if (e)
*e = errstr;
if (fd >= 0)
close (fd);
errno = err;
return -1;
}
if (connect (fd, addr, len) < 0)
{
errstr = "connecting socket";
goto fail;
}
return fd;
}
int OpenLocal (char const **e, char const *name)
{
sockaddr_un addr;
size_t len = strlen (name);
if (len >= sizeof (addr.sun_path))
{
errno = ENAMETOOLONG;
return -1;
}
memset (&addr, 0, offsetof (sockaddr_un, sun_path));
addr.sun_family = AF_UNIX;
memcpy (addr.sun_path, name, len + 1);
return OpenSocket (e, (sockaddr *)&addr, sizeof (addr));
}
int OpenInet6 (char const **e, char const *name, int port)
{
addrinfo *addrs = nullptr;
int fd = -1;
char const *errstr = nullptr;
fd = socket (AF_INET6, SOCK_STREAM, 0);
if (fd < 0)
{
errstr = "socket";
fail:;
int err = errno;
if (e)
*e = errstr;
if (fd >= 0)
close (fd);
if (addrs)
freeaddrinfo (addrs);
errno = err;
return -1;
}
addrinfo hints;
hints.ai_flags = AI_NUMERICSERV;
hints.ai_family = AF_INET6;
hints.ai_socktype = SOCK_STREAM;
hints.ai_protocol = 0;
hints.ai_addrlen = 0;
hints.ai_addr = nullptr;
hints.ai_canonname = nullptr;
hints.ai_next = nullptr;
/* getaddrinfo requires a port number, but is quite happy to accept
invalid ones. So don't rely on it. */
if (int err = getaddrinfo (name, "0", &hints, &addrs))
{
errstr = gai_strerror (err);
// What's the best errno to set?
errno = 0;
goto fail;
}
sockaddr_in6 addr;
memset (&addr, 0, sizeof (addr));
addr.sin6_family = AF_INET6;
for (struct addrinfo *next = addrs; next; next = next->ai_next)
if (next->ai_family == AF_INET6
&& next->ai_socktype == SOCK_STREAM)
{
sockaddr_in6 *in6 = (sockaddr_in6 *)next->ai_addr;
in6->sin6_port = htons (port);
if (ntohs (in6->sin6_port) != port)
errno = EINVAL;
else if (!connect (fd, next->ai_addr, next->ai_addrlen))
goto done;
}
errstr = "connecting";
goto fail;
done:;
freeaddrinfo (addrs);
return fd;
}
}
#endif