io/bits/poll2.h

   1 /* Checking macros for poll functions.
   2    Copyright (C) 2012-2021 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 #ifndef _SYS_POLL_H
  20 # error "Never include <bits/poll2.h> directly; use <sys/poll.h> instead."
  21 #endif
  22
  23
  24 __BEGIN_DECLS
  25
  26 extern int __REDIRECT (__poll_alias, (struct pollfd *__fds, nfds_t __nfds,
  27                                       int __timeout), poll);
  28 extern int __poll_chk (struct pollfd *__fds, nfds_t __nfds, int __timeout,
  29                        __SIZE_TYPE__ __fdslen);
  30 extern int __REDIRECT (__poll_chk_warn, (struct pollfd *__fds, nfds_t __nfds,
  31                                          int __timeout, __SIZE_TYPE__ __fdslen),
  32                        __poll_chk)
  33   __warnattr ("poll called with fds buffer too small file nfds entries");
  34
  35 __fortify_function int
  36 poll (struct pollfd *__fds, nfds_t __nfds, int __timeout)
  37 {
  38   if (__glibc_objsize (__fds) != (__SIZE_TYPE__) -1)
  39     {
  40       if (! __builtin_constant_p (__nfds))
  41         return __poll_chk (__fds, __nfds, __timeout, __glibc_objsize (__fds));
  42       else if (__glibc_objsize (__fds) / sizeof (*__fds) < __nfds)
  43         return __poll_chk_warn (__fds, __nfds, __timeout,
  44                                 __glibc_objsize (__fds));
  45     }
  46
  47   return __poll_alias (__fds, __nfds, __timeout);
  48 }
  49
  50
  51 #ifdef __USE_GNU
  52 extern int __REDIRECT (__ppoll_alias, (struct pollfd *__fds, nfds_t __nfds,
  53                                        const struct timespec *__timeout,
  54                                        const __sigset_t *__ss), ppoll);
  55 extern int __ppoll_chk (struct pollfd *__fds, nfds_t __nfds,
  56                         const struct timespec *__timeout,
  57                         const __sigset_t *__ss, __SIZE_TYPE__ __fdslen);
  58 extern int __REDIRECT (__ppoll_chk_warn, (struct pollfd *__fds, nfds_t __nfds,
  59                                           const struct timespec *__timeout,
  60                                           const __sigset_t *__ss,
  61                                           __SIZE_TYPE__ __fdslen),
  62                        __ppoll_chk)
  63   __warnattr ("ppoll called with fds buffer too small file nfds entries");
  64
  65 __fortify_function int
  66 ppoll (struct pollfd *__fds, nfds_t __nfds, const struct timespec *__timeout,
  67        const __sigset_t *__ss)
  68 {
  69   if (__glibc_objsize (__fds) != (__SIZE_TYPE__) -1)
  70     {
  71       if (! __builtin_constant_p (__nfds))
  72         return __ppoll_chk (__fds, __nfds, __timeout, __ss,
  73                             __glibc_objsize (__fds));
  74       else if (__glibc_objsize (__fds) / sizeof (*__fds) < __nfds)
  75         return __ppoll_chk_warn (__fds, __nfds, __timeout, __ss,
  76                                  __glibc_objsize (__fds));
  77     }
  78
  79   return __ppoll_alias (__fds, __nfds, __timeout, __ss);
  80 }
  81 #endif
  82
  83 __END_DECLS