sysdeps/unix/sysv/linux/fcntl_nocancel.c

   1 /* Linux fcntl syscall implementation -- non-cancellable.
   2    Copyright (C) 2018 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <fcntl.h>
  20 #include <stdarg.h>
  21 #include <errno.h>
  22 #include <sysdep-cancel.h>
  23 #include <not-cancel.h>
  24
  25 #ifndef __NR_fcntl64
  26 # define __NR_fcntl64 __NR_fcntl
  27 #endif
  28
  29 #ifndef FCNTL_ADJUST_CMD
  30 # define FCNTL_ADJUST_CMD(__cmd) __cmd
  31 #endif
  32
  33 int
  34 __fcntl64_nocancel (int fd, int cmd, ...)
  35 {
  36   va_list ap;
  37   void *arg;
  38
  39   va_start (ap, cmd);
  40   arg = va_arg (ap, void *);
  41   va_end (ap);
  42
  43   cmd = FCNTL_ADJUST_CMD (cmd);
  44
  45   return __fcntl64_nocancel_adjusted (fd, cmd, arg);
  46 }
  47 hidden_def (__fcntl64_nocancel)
  48
  49 int
  50 __fcntl64_nocancel_adjusted (int fd, int cmd, void *arg)
  51 {
  52   if (cmd == F_GETOWN)
  53     {
  54       INTERNAL_SYSCALL_DECL (err);
  55       struct f_owner_ex fex;
  56       int res = INTERNAL_SYSCALL_CALL (fcntl64, err, fd, F_GETOWN_EX, &fex);
  57       if (!INTERNAL_SYSCALL_ERROR_P (res, err))
  58         return fex.type == F_OWNER_GID ? -fex.pid : fex.pid;
  59
  60       return INLINE_SYSCALL_ERROR_RETURN_VALUE
  61         (INTERNAL_SYSCALL_ERRNO (res, err));
  62     }
  63
  64   return INLINE_SYSCALL_CALL (fcntl64, fd, cmd, (void *) arg);
  65 }