glibc/sysdeps/unix/sysv/sysv4/waitpid.c
1997-06-23 21:54:51 +00:00

121 lines
3.6 KiB
C

/* Copyright (C) 1993, 1994, 1995, 1996, 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Brendan Kehoe (brendan@zen.org).
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 <sys/wait.h>
#include <sys/types.h>
#include <stddef.h>
#include "siginfo.h"
typedef enum __idtype
{
/* Look for processes based upon a given PID. */
P_PID,
/* Look for processes based upon a given process-group ID. */
P_PGID = 2,
/* Look for any process. */
P_ALL = 7,
} __idtype_t;
extern __pid_t __getpgid __P ((__pid_t pid));
extern int __waitid __P ((__idtype_t idtype, __pid_t id,
__siginfo_t *infop, int options));
/* Wait for a child matching PID to die.
If PID is greater than 0, match any process whose process ID is PID.
If PID is (pid_t) -1, match any process.
If PID is (pid_t) 0, match any process with the
same process group as the current process.
If PID is less than -1, match any process whose
process group is the absolute value of PID.
If the WNOHANG bit is set in OPTIONS, and that child
is not already dead, return (pid_t) 0. If successful,
return PID and store the dead child's status in STAT_LOC.
Return (pid_t) -1 for errors. If the WUNTRACED bit is set in OPTIONS,
return status for stopped children; otherwise don't. */
__pid_t
__libc_waitpid (__pid_t pid, int *stat_loc, int options)
{
__idtype_t idtype;
__pid_t tmp_pid = pid;
__siginfo_t infop;
if (pid <= WAIT_MYPGRP)
{
if (pid == WAIT_ANY)
{
/* Request the status for any child. */
idtype = P_ALL;
}
else if (pid == WAIT_MYPGRP)
{
/* Request the status for any child process that has
a pgid that's equal to that of our parent. */
tmp_pid = __getpgid (0);
idtype = P_PGID;
}
else /* PID < -1 */
{
/* Request the status for any child whose pgid is equal
to the absolute value of PID. */
tmp_pid = pid & ~0; /* XXX not pseudo-insn */
idtype = P_PGID;
}
}
else
{
/* Request the status for the child whose pid is PID. */
idtype = P_PID;
}
if (__waitid (idtype, tmp_pid, &infop, options | WEXITED | WTRAPPED) < 0)
return -1;
switch (infop.__code)
{
case EXITED:
*stat_loc = W_EXITCODE (infop.__status, 0);
break;
case STOPPED:
case TRAPPED:
*stat_loc = W_STOPCODE (infop.__status);
break;
case KILLED:
/* Don't know what to do with continue, since it isn't documented.
Putting it here seemed the right place though. */
case CONTINUED:
*stat_loc = infop.__status;
/* FALLTHROUGH */
case CORED:
*stat_loc |= WCOREFLAG;
break;
}
/* Return the PID out of the INFOP structure instead of the one we were
called with, to account for cases of being called with -1 to signify
any PID. */
return infop.__pid;
}
weak_alias (__libc_waitpid, __waitpid)
weak_alias (__libc_waitpid, waitpid)