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/* vi: set sw=4 ts=4: */
/*
* Rexec program for system have fork() as vfork() with foreground option
*
* Copyright (C) Vladimir N. Oleynik <dzo@simtreas.ru>
* Copyright (C) 2003 Russ Dill <Russ.Dill@asu.edu>
*
* daemon() portion taken from uClibc:
*
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* Modified for uClibc by Erik Andersen <andersee@debian.org>
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
#include <paths.h>
#include "libbb.h"
#ifdef BB_NOMMU
void vfork_daemon_rexec(int nochdir, int noclose, char **argv)
{
int fd;
setsid();
if (!nochdir)
xchdir("/");
if (!noclose) {
/* if "/dev/null" doesn't exist, bail out! */
fd = xopen(bb_dev_null, O_RDWR);
dup2(fd, STDIN_FILENO);
dup2(fd, STDOUT_FILENO);
dup2(fd, STDERR_FILENO);
while (fd > 2)
close(fd--);
}
switch (vfork()) {
case 0: /* child */
/* Make certain we are not a session leader, or else we
* might reacquire a controlling terminal */
if (vfork())
_exit(0);
/* High-order bit of first char in argv[0] is a hidden
* "we have (alrealy) re-execed, don't do it again" flag */
argv[0][0] |= 0x80;
execv(CONFIG_BUSYBOX_EXEC_PATH, argv);
bb_perror_msg_and_die("exec %s", CONFIG_BUSYBOX_EXEC_PATH);
case -1: /* error */
bb_perror_msg_and_die("vfork");
default: /* parent */
exit(0);
}
}
#endif /* BB_NOMMU */
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