1 /*-
2 * Copyright (c) 1980 The Regents of the University of California.
3 * 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 static char sccsid[] = "@(#)unctime.c 5.4 (Berkeley) 3/7/91";
36 #endif /* not lint */
37
38 #include <sys/types.h>
39 #include <time.h>
40 #include <stdio.h>
41 #ifdef __STDC__
42 #include <stdlib.h>
43 #include <string.h>
44 #endif
45
46 /*
47 * Convert a ctime(3) format string into a system format date.
48 * Return the date thus calculated.
49 *
50 * Return -1 if the string is not in ctime format.
51 */
52
53 /*
54 * Offsets into the ctime string to various parts.
55 */
56
57 #define E_MONTH 4
58 #define E_DAY 8
59 #define E_HOUR 11
60 #define E_MINUTE 14
61 #define E_SECOND 17
62 #define E_YEAR 20
63
64 static int lookup();
65
66 time_t
unctime(str)67 unctime(str)
68 char *str;
69 {
70 struct tm then;
71 char dbuf[30];
72 time_t emitl();
73
74 if (strlen(str) != 25)
75 str[25] = 0;
76 strcpy(dbuf, str);
77 dbuf[E_MONTH+3] = 0;
78 if ((then.tm_mon = lookup(&dbuf[E_MONTH])) < 0)
79 return (-1);
80 then.tm_mday = atoi(&dbuf[E_DAY]);
81 then.tm_hour = atoi(&dbuf[E_HOUR]);
82 then.tm_min = atoi(&dbuf[E_MINUTE]);
83 then.tm_sec = atoi(&dbuf[E_SECOND]);
84 then.tm_year = atoi(&dbuf[E_YEAR]) - 1900;
85 return(emitl(&then));
86 }
87
88 static char months[] =
89 "JanFebMarAprMayJunJulAugSepOctNovDec";
90
91 static int
lookup(str)92 lookup(str)
93 char *str;
94 {
95 register char *cp, *cp2;
96
97 for (cp = months, cp2 = str; *cp != 0; cp += 3)
98 if (strncmp(cp, cp2, 3) == 0)
99 return((cp-months) / 3);
100 return(-1);
101 }
102 /*
103 * Routine to convert a localtime(3) format date back into
104 * a system format date.
105 *
106 * Use a binary search.
107 */
108
109 struct tm *localtime();
110 static int dcmp();
111
112 time_t
emitl(dp)113 emitl(dp)
114 struct tm *dp;
115 {
116 time_t conv;
117 register int i, bit;
118 struct tm dcopy;
119
120 dcopy = *dp;
121 dp = &dcopy;
122 conv = 0;
123 for (i = 30; i >= 0; i--) {
124 bit = 1 << i;
125 conv |= bit;
126 if (dcmp(localtime(&conv), dp) > 0)
127 conv &= ~bit;
128 }
129 return(conv);
130 }
131
132 /*
133 * Compare two localtime dates, return result.
134 */
135
136 #define DECIDE(a) \
137 if (dp->a > dp2->a) \
138 return(1); \
139 if (dp->a < dp2->a) \
140 return(-1)
141
142 static int
dcmp(dp,dp2)143 dcmp(dp, dp2)
144 register struct tm *dp, *dp2;
145 {
146
147 DECIDE(tm_year);
148 DECIDE(tm_mon);
149 DECIDE(tm_mday);
150 DECIDE(tm_hour);
151 DECIDE(tm_min);
152 DECIDE(tm_sec);
153 return(0);
154 }
155