sysdeps/unix/sysv/linux/poll.c

   1 /* Linux poll implementation.
   2    Copyright (C) 2017-2024 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    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <sys/poll.h>
  21
  22 #include <sysdep-cancel.h>
  23 #include <sys/syscall.h>
  24
  25 int
  26 __poll (struct pollfd *fds, nfds_t nfds, int timeout)
  27 {
  28 #ifdef __NR_poll
  29   return SYSCALL_CANCEL (poll, fds, nfds, timeout);
  30 #else
  31   struct timespec timeout_ts;
  32   struct timespec *timeout_ts_p = NULL;
  33
  34   if (timeout >= 0)
  35     {
  36       timeout_ts.tv_sec = timeout / 1000;
  37       timeout_ts.tv_nsec = (timeout % 1000) * 1000000;
  38       timeout_ts_p = &timeout_ts;
  39     }
  40
  41   return SYSCALL_CANCEL (ppoll, fds, nfds, timeout_ts_p, NULL, 0);
  42 #endif
  43 }
  44 libc_hidden_def (__poll)
  45 weak_alias (__poll, poll)
  46 strong_alias (__poll, __libc_poll)