l4/pkg/uclibc/lib/contrib/uclibc/libc/sysdeps/linux/common/waitid.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Copyright (C) 2007 Erik Andersen <andersen@uclibc.org>
   4  *
   5  * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
   6  */
   7
   8 #include <features.h>
   9
  10 #if defined __USE_SVID || defined __USE_XOPEN
  11 # include <string.h>
  12 # include <sys/types.h>
  13 # include <sys/wait.h>
  14 # include <sys/syscall.h>
  15
  16 # ifdef __NR_waitid
  17
  18 #  ifdef __UCLIBC_HAS_THREADS_NATIVE__
  19 #  include <sysdep-cancel.h>
  20 #  else
  21 #  define SINGLE_THREAD_P 1
  22 #  endif
  23
  24 /* The waitid() POSIX interface takes 4 arguments, but the kernel function
  25  * actually takes 5.  The fifth is a pointer to struct rusage.  Make sure
  26  * we pass NULL rather than letting whatever was in the register bleed up.
  27  */
  28 #define __NR_waitid5 __NR_waitid
  29 static __always_inline
  30 _syscall5(int, waitid5, idtype_t, idtype, id_t, id, siginfo_t*, infop,
  31                  int, options, struct rusage*, ru)
  32 # endif
  33
  34 int waitid(idtype_t idtype, id_t id, siginfo_t *infop, int options)
  35 {
  36 # ifdef __NR_waitid
  37  if (SINGLE_THREAD_P)
  38                 return waitid5(idtype, id, infop, options, NULL);
  39
  40 #  ifdef __UCLIBC_HAS_THREADS_NATIVE__
  41         int oldtype = LIBC_CANCEL_ASYNC ();
  42         int result = waitid5(idtype, id, infop, options, NULL);
  43         LIBC_CANCEL_RESET (oldtype);
  44         return result;
  45 #  endif
  46
  47 # elif defined __NR_waitpid
  48         switch (idtype) {
  49                 case P_PID:
  50                         if (id <= 0)
  51                                 goto invalid;
  52                         break;
  53                 case P_PGID:
  54                         if (id < 0 || id == 1)
  55                                 goto invalid;
  56                         id = -id;
  57                         break;
  58                 case P_ALL:
  59                         id = -1;
  60                         break;
  61                 default:
  62                 invalid:
  63                         __set_errno(EINVAL);
  64                         return -1;
  65         }
  66
  67         memset(infop, 0, sizeof *infop);
  68         infop->si_pid = waitpid(id, &infop->si_status, options
  69 #  ifdef WEXITED
  70                                            &~ WEXITED
  71 #  endif
  72                                           );
  73         if (infop->si_pid < 0)
  74                 return infop->si_pid;
  75         return 0;
  76 # else
  77  __set_errno(ENOSYS);
  78  return -1;
  79 # endif
  80 }
  81 #endif