xref: /onnv-gate/usr/src/cmd/ypcmd/yppasswd/yplckpwdf.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate  * Copyright (c) 1996-2001 by Sun Microsystems, Inc.
24*0Sstevel@tonic-gate  * All rights reserved.
25*0Sstevel@tonic-gate  */
26*0Sstevel@tonic-gate 
27*0Sstevel@tonic-gate /*	Copyright (c) 1988 AT&T	*/
28*0Sstevel@tonic-gate /*	  All Rights Reserved  	*/
29*0Sstevel@tonic-gate 
30*0Sstevel@tonic-gate 
31*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
32*0Sstevel@tonic-gate 
33*0Sstevel@tonic-gate #include <stdio.h>
34*0Sstevel@tonic-gate #include <signal.h>
35*0Sstevel@tonic-gate #include <fcntl.h>
36*0Sstevel@tonic-gate #include <unistd.h> /* alarm() */
37*0Sstevel@tonic-gate 
38*0Sstevel@tonic-gate #define	S_WAITTIME	15
39*0Sstevel@tonic-gate 
40*0Sstevel@tonic-gate static struct flock flock =	{
41*0Sstevel@tonic-gate 			0,	/* l_type */
42*0Sstevel@tonic-gate 			0,	/* l_whence */
43*0Sstevel@tonic-gate 			0,	/* l_start */
44*0Sstevel@tonic-gate 			0,	/* l_len */
45*0Sstevel@tonic-gate 			0,	/* l_sysid */
46*0Sstevel@tonic-gate 			0	/* l_pid */
47*0Sstevel@tonic-gate 			};
48*0Sstevel@tonic-gate 
49*0Sstevel@tonic-gate /*
50*0Sstevel@tonic-gate  *	yplckpwdf() returns a 0 for a successful lock within W_WAITTIME
51*0Sstevel@tonic-gate  *	and -1 otherwise
52*0Sstevel@tonic-gate  */
53*0Sstevel@tonic-gate 
54*0Sstevel@tonic-gate static int fildes = -1;
55*0Sstevel@tonic-gate extern char lockfile[];
56*0Sstevel@tonic-gate 
57*0Sstevel@tonic-gate /* ARGSUSED */
58*0Sstevel@tonic-gate static void
almhdlr(int sig)59*0Sstevel@tonic-gate almhdlr(int sig)
60*0Sstevel@tonic-gate {
61*0Sstevel@tonic-gate }
62*0Sstevel@tonic-gate 
63*0Sstevel@tonic-gate int
yplckpwdf()64*0Sstevel@tonic-gate yplckpwdf()
65*0Sstevel@tonic-gate {
66*0Sstevel@tonic-gate 	int retval;
67*0Sstevel@tonic-gate 	if ((fildes = creat(lockfile, 0600)) == -1)
68*0Sstevel@tonic-gate 		return (-1);
69*0Sstevel@tonic-gate 
70*0Sstevel@tonic-gate 	flock.l_type = F_WRLCK;
71*0Sstevel@tonic-gate 	(void) sigset(SIGALRM, almhdlr);
72*0Sstevel@tonic-gate 	(void) alarm(S_WAITTIME);
73*0Sstevel@tonic-gate 	retval = fcntl(fildes, F_SETLKW, (int)&flock);
74*0Sstevel@tonic-gate 	(void) alarm(0);
75*0Sstevel@tonic-gate 	(void) sigset(SIGALRM, SIG_DFL);
76*0Sstevel@tonic-gate 	return (retval);
77*0Sstevel@tonic-gate 
78*0Sstevel@tonic-gate }
79*0Sstevel@tonic-gate 
80*0Sstevel@tonic-gate /*
81*0Sstevel@tonic-gate  *	ypulckpwdf() returns 0 for a successful unlock and -1 otherwise
82*0Sstevel@tonic-gate  */
83*0Sstevel@tonic-gate int
ypulckpwdf()84*0Sstevel@tonic-gate ypulckpwdf()
85*0Sstevel@tonic-gate {
86*0Sstevel@tonic-gate 	if (fildes == -1)
87*0Sstevel@tonic-gate 		return (-1);
88*0Sstevel@tonic-gate 
89*0Sstevel@tonic-gate 	flock.l_type = F_UNLCK;
90*0Sstevel@tonic-gate 	(void) fcntl(fildes, F_SETLK, (int)&flock);
91*0Sstevel@tonic-gate 	(void) close(fildes);
92*0Sstevel@tonic-gate 	fildes = -1;
93*0Sstevel@tonic-gate 	return (0);
94*0Sstevel@tonic-gate 
95*0Sstevel@tonic-gate }
96