1  /* Copyright (C) 1992-2023 Free Software Foundation, Inc.
       2     This file is part of the GNU C Library.
       3  
       4     The GNU C Library is free software; you can redistribute it and/or
       5     modify it under the terms of the GNU Lesser General Public
       6     License as published by the Free Software Foundation; either
       7     version 2.1 of the License, or (at your option) any later version.
       8  
       9     The GNU C Library is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12     Lesser General Public License for more details.
      13  
      14     You should have received a copy of the GNU Lesser General Public
      15     License along with the GNU C Library; if not, see
      16     <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <errno.h>
      19  #include <fcntl.h>
      20  #include <fcntl-internal.h>
      21  #include <sys/socket.h>
      22  #include <unistd.h>
      23  
      24  #include <hurd.h>
      25  #include <hurd/fd.h>
      26  #include <hurd/socket.h>
      27  
      28  /* Create two new sockets, of type TYPE in domain DOMAIN and using
      29     protocol PROTOCOL, which are connected to each other, and put file
      30     descriptors for them in FDS[0] and FDS[1].  If PROTOCOL is zero,
      31     one will be chosen automatically.  Returns 0 on success, -1 for errors.  */
      32  int
      33  __socketpair (int domain, int type, int protocol, int fds[2])
      34  {
      35    error_t err;
      36    socket_t server, sock1, sock2;
      37    int d1, d2;
      38    int flags = sock_to_o_flags (type & ~SOCK_TYPE_MASK);
      39    type &= SOCK_TYPE_MASK;
      40  
      41    if (flags & ~(O_CLOEXEC | O_NONBLOCK))
      42      return __hurd_fail (EINVAL);
      43  
      44    if (fds == NULL)
      45      return __hurd_fail (EINVAL);
      46  
      47    /* Find the domain's socket server.  */
      48    server = _hurd_socket_server (domain, 0);
      49    if (server == MACH_PORT_NULL)
      50      return -1;
      51  
      52    /* Create two sockets and connect them together.  */
      53  
      54    err = __socket_create (server, type, protocol, &sock1);
      55    if (err == MACH_SEND_INVALID_DEST || err == MIG_SERVER_DIED
      56        || err == MIG_BAD_ID || err == EOPNOTSUPP)
      57      {
      58        /* On the first use of the socket server during the operation,
      59  	 allow for the old server port dying.  */
      60        server = _hurd_socket_server (domain, 1);
      61        if (server == MACH_PORT_NULL)
      62  	return -1;
      63        err = __socket_create (server, type, protocol, &sock1);
      64      }
      65    /* TODO: do we need special ERR massaging here, like it is done in
      66       __socket?  */
      67    if (! err)
      68      {
      69        if (flags & O_NONBLOCK)
      70  	err = __io_set_some_openmodes (sock1, O_NONBLOCK);
      71        /* TODO: do we need special ERR massaging after the previous call?  */
      72      }
      73    if (err)
      74      return __hurd_fail (err);
      75    if (err = __socket_create (server, type, protocol, &sock2))
      76      {
      77        __mach_port_deallocate (__mach_task_self (), sock1);
      78        return __hurd_fail (err);
      79      }
      80    if (flags & O_NONBLOCK)
      81      err = __io_set_some_openmodes (sock2, O_NONBLOCK);
      82    /* TODO: do we need special ERR massaging after the previous call?  */
      83    if (! err)
      84      err = __socket_connect2 (sock1, sock2);
      85    if (err)
      86      {
      87        __mach_port_deallocate (__mach_task_self (), sock1);
      88        __mach_port_deallocate (__mach_task_self (), sock2);
      89        return __hurd_fail (err);
      90      }
      91  
      92    /* Put the sockets into file descriptors.  */
      93  
      94    d1 = _hurd_intern_fd (sock1, O_IGNORE_CTTY | flags, 1);
      95    if (d1 < 0)
      96      {
      97        __mach_port_deallocate (__mach_task_self (), sock2);
      98        return -1;
      99      }
     100    d2 = _hurd_intern_fd (sock2, O_IGNORE_CTTY | flags, 1);
     101    if (d2 < 0)
     102      {
     103        err = errno;
     104        (void) __close (d1);
     105        return __hurd_fail (err);
     106      }
     107  
     108    fds[0] = d1;
     109    fds[1] = d2;
     110    return 0;
     111  }
     112  
     113  weak_alias (__socketpair, socketpair)