newlib/winsup/cygwin/wait.cc

128 lines
2.7 KiB
C++

/* wait.cc: Posix wait routines.
Copyright 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003 Red Hat, Inc.
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#include "winsup.h"
#include <sys/wait.h>
#include <stdlib.h>
#include "cygerrno.h"
#include "sigproc.h"
#include "perthread.h"
#include "thread.h"
/* This is called _wait and not wait because the real wait is defined
in libc/syscalls/syswait.c. It calls us. */
extern "C" pid_t
wait (int *status)
{
return wait4 (-1, status, 0, NULL);
}
extern "C" pid_t
waitpid (pid_t intpid, int *status, int options)
{
return wait4 (intpid, status, options, NULL);
}
extern "C" pid_t
wait3 (int *status, int options, struct rusage *r)
{
return wait4 (-1, status, options, r);
}
/* Wait for any child to complete.
* Note: this is not thread safe. Use of wait in multiple threads will
* not work correctly.
*/
extern "C" pid_t
wait4 (int intpid, int *status, int options, struct rusage *r)
{
int res;
waitq *w;
HANDLE waitfor;
pthread_testcancel ();
while (1)
{
sig_dispatch_pending ();
bool sawsig = false;
if (options & ~(WNOHANG | WUNTRACED))
{
set_errno (EINVAL);
return -1;
}
if (r)
memset (r, 0, sizeof (*r));
if ((w = (waitq *) waitq_storage.get ()) == NULL)
w = (waitq *) waitq_storage.create ();
w->pid = intpid;
w->options = options;
w->rusage = r;
sigproc_printf ("calling proc_subproc, pid %d, options %d",
w->pid, w->options);
if (!proc_subproc (PROC_WAIT, (DWORD) w))
{
set_errno (ENOSYS);
paranoid_printf ("proc_subproc returned 0");
res = -1;
goto done;
}
if ((waitfor = w->ev) == NULL)
goto nochildren;
res = pthread::cancelable_wait (waitfor, INFINITE);
sigproc_printf ("%d = WaitForSingleObject (...)", res);
if (w->ev == NULL)
{
nochildren:
/* found no children */
set_errno (ECHILD);
res = -1;
goto done;
}
if (w->status == -1)
{
set_sig_errno (EINTR);
call_signal_handler_now ();
sawsig = true;
res = -1;
}
else if (res != WAIT_OBJECT_0)
{
/* We shouldn't set errno to any random value if we can help it.
See the Posix manual for a list of valid values for `errno'. */
set_errno (EINVAL);
res = -1;
}
else if ((res = w->pid) != 0 && status)
*status = w->status;
done:
if (!sawsig || !call_signal_handler_now ())
break;
}
sigproc_printf ("intpid %d, status %p, w->status %d, options %d, res %d",
intpid, status, w->status, options, res);
w->status = -1;
if (res < 0)
sigproc_printf ("*** errno = %d", get_errno ());
return res;
}