sortix-mirror/libc/sys/socket/socketpair.c
Jonas 'Sortie' Termansen 2b72262b4f Relicense Sortix to the ISC license.
I hereby relicense all my work on Sortix under the ISC license as below.

All Sortix contributions by other people are already under this license,
are not substantial enough to be copyrightable, or have been removed.

All imported code from other projects is compatible with this license.

All GPL licensed code from other projects had previously been removed.

Copyright 2011-2016 Jonas 'Sortie' Termansen and contributors.

Permission to use, copy, modify, and distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
2016-03-05 22:21:50 +01:00

145 lines
3.7 KiB
C

/*
* Copyright (c) 2016 Jonas 'Sortie' Termansen.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* sys/socket/socketpair.c
* Create a pair of connected sockets.
*/
#include <sys/socket.h>
#include <sys/un.h>
#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#define FLAGS_MASK (SOCK_NONBLOCK | SOCK_CLOEXEC | SOCK_CLOFORK)
#define TYPE_MASK (~FLAGS_MASK)
#define FLAGS(x) ((x) & FLAGS_MASK)
#define TYPE(x) ((x) & TYPE_MASK)
static char randchar(void)
{
int index = arc4random_uniform(26 + 26 + 10);
if ( index < 26 )
return 'a' + index;
if ( index < 26 + 26 )
return 'A' + (index - 26);
return '0' + (index - (26 + 26));
}
struct accept_thread
{
int listen_fd;
int fd;
int flags;
int errnum;
};
static void* accept_thread(void* arg_ptr)
{
struct accept_thread* arg = (struct accept_thread*) arg_ptr;
arg->fd = accept4(arg->listen_fd, NULL, NULL, arg->flags);
arg->errnum = errno;
return NULL;
}
static int socketpair_unix_stream(int flags, int fds[2])
{
char templ[] = "/tmp/socketpair.XXXXXXXXXX";
size_t templ_len = strlen(templ);
while ( true )
{
for ( size_t i = 0; i < 10; i++ )
templ[templ_len - i] = randchar();
int listen_flags = SOCK_CLOEXEC | SOCK_CLOFORK;
int listen_fd = socket(AF_UNIX, SOCK_STREAM | listen_flags, 0);
if ( listen_fd < 0 )
return -1;
struct sockaddr_un addr;
memset(&addr, 0, sizeof(addr));
addr.sun_family = AF_UNIX;
memcpy(addr.sun_path, templ, templ_len + 1);
if ( bind(listen_fd, (struct sockaddr*) &addr, sizeof(addr)) < 0 )
return -1;
if ( listen(listen_fd, 1) < 0 )
{
if ( errno == EADDRINUSE )
continue;
close(listen_fd);
return -1;
}
int client_flags = flags & ~SOCK_NONBLOCK;
int client_fd = socket(AF_UNIX, SOCK_STREAM | client_flags, 0);
if ( client_fd < 0 )
{
int errnum = errno;
close(listen_fd);
unlink(templ);
return errno = errnum, -1;
}
struct accept_thread arg;
arg.listen_fd = listen_fd;
arg.flags = flags;
pthread_attr_t thread_attr;
pthread_attr_init(&thread_attr);
pthread_attr_setstacksize(&thread_attr, 8192);
pthread_t thread;
int ret = pthread_create(&thread, &thread_attr, accept_thread, &arg);
pthread_attr_destroy(&thread_attr);
if ( ret != 0 )
{
close(listen_fd);
close(client_fd);
unlink(templ);
return errno = ret, -1;
}
ret = connect(client_fd, (struct sockaddr*) &addr, sizeof(addr));
pthread_join(thread, NULL);
if ( ret < 0 )
{
int errnum = errno;
close(listen_fd);
close(client_fd);
unlink(templ);
return errno = errnum, -1;
}
close(listen_fd);
unlink(templ);
if ( flags & SOCK_NONBLOCK )
fcntl(client_fd, F_SETFL, flags);
fds[0] = client_fd;
fds[1] = arg.fd;
return 0;
}
}
int socketpair(int family, int type, int protocol, int fds[2])
{
if ( family == AF_UNIX )
{
if ( protocol != 0 )
return errno = EPROTONOSUPPORT, -1;
if ( TYPE(type) == SOCK_STREAM )
return socketpair_unix_stream(FLAGS(type), fds);
else
return errno = EPROTOTYPE, -1;
}
return errno = EAFNOSUPPORT, -1;
}