xref: /freebsd/sbin/dump/unctime.c (revision a8445737e740901f5f2c8d24c12ef7fc8b00134e)
1 /*-
2  * Copyright (c) 1980, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 #if 0
36 static char sccsid[] = "@(#)unctime.c	8.2 (Berkeley) 6/14/94";
37 #endif
38 static const char rcsid[] =
39 	"$Id$";
40 #endif /* not lint */
41 
42 #include <time.h>
43 #ifdef __STDC__
44 #include <stdlib.h>
45 #include <string.h>
46 #endif
47 
48 /*
49  * Convert a ctime(3) format string into a system format date.
50  * Return the date thus calculated.
51  *
52  * Return -1 if the string is not in ctime format.
53  */
54 
55 /*
56  * Offsets into the ctime string to various parts.
57  */
58 
59 #define	E_MONTH		4
60 #define	E_DAY		8
61 #define	E_HOUR		11
62 #define	E_MINUTE	14
63 #define	E_SECOND	17
64 #define	E_YEAR		20
65 
66 static	int lookup __P((char *));
67 
68 
69 time_t
70 unctime(str)
71 	char *str;
72 {
73 	struct tm then;
74 	char dbuf[26];
75 
76 	(void) strncpy(dbuf, str, sizeof(dbuf) - 1);
77 	dbuf[sizeof(dbuf) - 1] = '\0';
78 	dbuf[E_MONTH+3] = '\0';
79 	if ((then.tm_mon = lookup(&dbuf[E_MONTH])) < 0)
80 		return (-1);
81 	then.tm_mday = atoi(&dbuf[E_DAY]);
82 	then.tm_hour = atoi(&dbuf[E_HOUR]);
83 	then.tm_min = atoi(&dbuf[E_MINUTE]);
84 	then.tm_sec = atoi(&dbuf[E_SECOND]);
85 	then.tm_year = atoi(&dbuf[E_YEAR]) - 1900;
86 	then.tm_isdst = -1;
87 	return(mktime(&then));
88 }
89 
90 static char months[] =
91 	"JanFebMarAprMayJunJulAugSepOctNovDec";
92 
93 static int
94 lookup(str)
95 	char *str;
96 {
97 	register char *cp, *cp2;
98 
99 	for (cp = months, cp2 = str; *cp != '\0'; cp += 3)
100 		if (strncmp(cp, cp2, 3) == 0)
101 			return((cp-months) / 3);
102 	return(-1);
103 }
104