sysdeps/unix/sysv/linux/waitid.c

   1 /* Linux implementation of waitid.
   2    Copyright (C) 2004 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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <errno.h>
  21 #include <sys/wait.h>
  22 #include <kernel-features.h>
  23 #include <sysdep.h>
  24
  25
  26 #ifdef __NR_waitid
  27
  28 # if __ASSUME_WAITID_SYSCALL > 0
  29
  30 static inline int
  31 do_waitid (idtype_t idtype, id_t id, siginfo_t *infop, int options)
  32 {
  33   /* The unused fifth argument is a `struct rusage *' that we could
  34      pass if we were using waitid to simulate wait3/wait4.  */
  35   return INLINE_SYSCALL (waitid, 5, idtype, id, infop, options, NULL);
  36 }
  37 # define NO_DO_WAITID
  38
  39 # else
  40
  41 static int do_compat_waitid (idtype_t idtype, id_t id,
  42                              siginfo_t *infop, int options);
  43 # define DO_WAITID do_compat_waitid
  44
  45 static int
  46 do_waitid (idtype_t idtype, id_t id, siginfo_t *infop, int options)
  47 {
  48   static int waitid_works;
  49   if (waitid_works > 0)
  50     return INLINE_SYSCALL (waitid, 5, idtype, id, infop, options, NULL);
  51   if (waitid_works == 0)
  52     {
  53       int result = INLINE_SYSCALL (waitid, 5,
  54                                    idtype, id, infop, options, NULL);
  55       if (result < 0 && errno == ENOSYS)
  56         waitid_works = -1;
  57       else
  58         {
  59           waitid_works = 1;
  60           return result;
  61         }
  62     }
  63   return do_compat_waitid (idtype, id, infop, options);
  64 }
  65
  66 # endif
  67
  68 #endif
  69
  70 #include "sysdeps/posix/waitid.c"