glibc/sysdeps/posix/waitid.c

121 lines
3.1 KiB
C

/* Pseudo implementation of waitid.
Copyright (C) 1997, 1998 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Zack Weinberg <zack@rabi.phys.columbia.edu>, 1997.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <errno.h>
#include <signal.h>
#define __need_NULL
#include <stddef.h>
#include <sys/wait.h>
#include <sys/types.h>
#include <assert.h>
int
waitid (idtype, id, infop, options)
idtype_t idtype;
id_t id;
siginfo_t *infop;
int options;
{
pid_t pid, child;
int status;
switch (idtype)
{
case P_PID:
if(id <= 0)
goto invalid;
pid = (pid_t) id;
break;
case P_PGID:
if (id < 0 || id == 1)
goto invalid;
pid = (pid_t) -id;
break;
case P_ALL:
pid = -1;
break;
default:
invalid:
__set_errno (EINVAL);
return -1;
}
/* Technically we're supposed to return EFAULT if infop is bogus,
but that would involve mucking with signals, which is
too much hassle. User will have to deal with SIGSEGV/SIGBUS.
We just check for a null pointer. */
if (infop == NULL)
{
__set_errno (EFAULT);
return -1;
}
child = __waitpid (pid, &status, options);
if (child == -1)
/* `waitpid' set `errno' for us. */
return -1;
if (child == 0)
{
/* The WHOHANG bit in OPTIONS is set and there are children available
but none has a status for us. The XPG docs do not mention this
case so we clear the `siginfo_t' struct and return succesfully. */
infop->si_signo = 0;
infop->si_code = 0;
return 0;
}
/* Decode the status field and set infop members... */
infop->si_signo = SIGCHLD;
infop->si_pid = child;
infop->si_errno = 0;
if (WIFEXITED (status))
{
infop->si_code = CLD_EXITED;
infop->si_status = WEXITSTATUS (status);
}
else if (WIFSIGNALED (status))
{
infop->si_code = WCOREDUMP (status) ? CLD_DUMPED : CLD_KILLED;
infop->si_status = WTERMSIG (status);
}
else if (WIFSTOPPED (status))
{
infop->si_code = CLD_STOPPED;
infop->si_status = WSTOPSIG (status);
}
#ifdef WIFCONTINUED
else if (WIFCONTINUED (status))
{
infop->si_code = CLD_CONTINUED;
infop->si_status = SIGCONT;
}
#endif
else
/* Can't happen. */
assert (! "What?");
return 0;
}