xref: /illumos-gate/usr/src/cmd/backup/dump/unctime.c (revision ddb365bfc9e868ad24ccdcb0dc91af18b10df082)
1 /*
2  * Copyright (c) 1998,2001 by Sun Microsystems, Inc.
3  * All rights reserved.
4  */
5 
6 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
7 /*	  All Rights Reserved	*/
8 
9 /*
10  * Copyright (c) 1980 Regents of the University of California.
11  * All rights reserved.  The Berkeley software License Agreement
12  * specifies the terms and conditions for redistribution.
13  */
14 
15 #include <sys/types.h>
16 #include <time.h>
17 #include <string.h>
18 #include <stdlib.h>
19 /*
20  * Convert a ctime(3) format string into a system format date.
21  * Return the date thus calculated.
22  *
23  * Return -1 if the string is not in ctime format.
24  */
25 
26 /*
27  * Offsets into the ctime string to various parts.
28  */
29 
30 #define	E_MONTH		4
31 #define	E_DAY		8
32 #define	E_HOUR		11
33 #define	E_MINUTE	14
34 #define	E_SECOND	17
35 #define	E_YEAR		20
36 
37 #ifdef __STDC__
38 static int lookup(char *);
39 static time_t emitl(struct tm *);
40 #else
41 static int lookup();
42 static time_t emitl();
43 #endif
44 
45 time_t
46 unctime(str)
47 	char *str;
48 {
49 	struct tm then;
50 	char dbuf[30];
51 
52 	/* Definition of ctime(3) is 24 characters + newline + NUL */
53 	(void) strncpy(dbuf, str, 24);
54 	dbuf[24] = '\0';
55 	dbuf[E_MONTH+3] = '\0';
56 	then.tm_mon = lookup(&dbuf[E_MONTH]);
57 	if (then.tm_mon < 0) {
58 		return (-1);
59 	}
60 	then.tm_mday = atoi(&dbuf[E_DAY]);
61 	then.tm_hour = atoi(&dbuf[E_HOUR]);
62 	then.tm_min = atoi(&dbuf[E_MINUTE]);
63 	then.tm_sec = atoi(&dbuf[E_SECOND]);
64 	then.tm_year = atoi(&dbuf[E_YEAR]) - 1900;
65 	return (emitl(&then));
66 }
67 
68 static char months[] =
69 	"JanFebMarAprMayJunJulAugSepOctNovDec";
70 
71 static int
72 lookup(str)
73 	char *str;
74 {
75 	char *cp, *cp2;
76 
77 	for (cp = months, cp2 = str; *cp != 0; cp += 3)
78 		if (strncmp(cp, cp2, 3) == 0)
79 			/* LINTED ptr arith will give < INT_MAX result */
80 			return (((int)(cp-months)) / 3);
81 	return (-1);
82 }
83 /*
84  * Routine to convert a localtime(3) format date back into
85  * a system format date.
86  */
87 static time_t
88 emitl(dp)
89 	struct tm *dp;
90 {
91 	dp->tm_isdst = -1;
92 	return (mktime(dp));
93 }
94