xref: /netbsd-src/external/bsd/openldap/dist/servers/slapd/lock.c (revision 549b59ed3ccf0d36d3097190a0db27b770f3a839)
1 /*	$NetBSD: lock.c,v 1.3 2021/08/14 16:14:58 christos Exp $	*/
2 
3 /* lock.c - routines to open and apply an advisory lock to a file */
4 /* $OpenLDAP$ */
5 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
6  *
7  * Copyright 1998-2021 The OpenLDAP Foundation.
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted only as authorized by the OpenLDAP
12  * Public License.
13  *
14  * A copy of this license is available in the file LICENSE in the
15  * top-level directory of the distribution or, alternatively, at
16  * <http://www.OpenLDAP.org/license.html>.
17  */
18 /* Portions Copyright (c) 1995 Regents of the University of Michigan.
19  * All rights reserved.
20  *
21  * Redistribution and use in source and binary forms are permitted
22  * provided that this notice is preserved and that due credit is given
23  * to the University of Michigan at Ann Arbor. The name of the University
24  * may not be used to endorse or promote products derived from this
25  * software without specific prior written permission. This software
26  * is provided ``as is'' without express or implied warranty.
27  */
28 
29 #include <sys/cdefs.h>
30 __RCSID("$NetBSD: lock.c,v 1.3 2021/08/14 16:14:58 christos Exp $");
31 
32 #include "portable.h"
33 
34 #include <stdio.h>
35 
36 #include <ac/string.h>
37 #include <ac/socket.h>
38 #include <ac/time.h>
39 #include <ac/unistd.h>
40 
41 #ifdef HAVE_SYS_FILE_H
42 #include <sys/file.h>
43 #endif
44 
45 #include "slap.h"
46 #include <lutil.h>
47 
48 FILE *
lock_fopen(const char * fname,const char * type,FILE ** lfp)49 lock_fopen( const char *fname, const char *type, FILE **lfp )
50 {
51 	FILE	*fp;
52 	char	buf[MAXPATHLEN];
53 
54 	/* open the lock file */
55 	snprintf( buf, sizeof buf, "%s.lock", fname );
56 
57 	if ( (*lfp = fopen( buf, "w" )) == NULL ) {
58 		Debug( LDAP_DEBUG_ANY, "could not open \"%s\"\n", buf );
59 
60 		return( NULL );
61 	}
62 
63 	/* acquire the lock */
64 	ldap_lockf( fileno(*lfp) );
65 
66 	/* open the log file */
67 	if ( (fp = fopen( fname, type )) == NULL ) {
68 		Debug( LDAP_DEBUG_ANY, "could not open \"%s\"\n", fname );
69 
70 		ldap_unlockf( fileno(*lfp) );
71 		fclose( *lfp );
72 		*lfp = NULL;
73 		return( NULL );
74 	}
75 
76 	return( fp );
77 }
78 
79 int
lock_fclose(FILE * fp,FILE * lfp)80 lock_fclose( FILE *fp, FILE *lfp )
81 {
82 	int rc = fclose( fp );
83 	/* unlock */
84 	ldap_unlockf( fileno(lfp) );
85 	fclose( lfp );
86 
87 	return( rc );
88 }
89