projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 76797561 DF |
1 | /* |
| 2 | * Copyright (c) 1980 Regents of the University of California. | |
| 3 | * All rights reserved. The Berkeley software License Agreement | |
| 4 | * specifies the terms and conditions for redistribution. | |
| 5 | */ | |
| 6 | ||
| bbbe213d | 7 | #ifndef lint |
| 13298603 | 8 | static char sccsid[] = "@(#)unctime.c 5.3 (Berkeley) %G%"; |
| 36783b71 | 9 | #endif /* not lint */ |
| bbbe213d | 10 | |
| 6e1fe29b | 11 | #include <sys/types.h> |
| 13298603 | 12 | #include <time.h> |
| 50953c5b | 13 | #include <stdio.h> |
| 13298603 | 14 | #ifdef __STDC__ |
| 36783b71 CT |
15 | #include <stdlib.h> |
| 16 | #include <string.h> | |
| 13298603 | 17 | #endif |
| 36783b71 | 18 | |
| 6e1fe29b BJ |
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 | ||
| 36783b71 CT |
37 | static int lookup(); |
| 38 | ||
| 39 | time_t | |
| 40 | unctime(str) | |
| 6e1fe29b BJ |
41 | char *str; |
| 42 | { | |
| 43 | struct tm then; | |
| 44 | char dbuf[30]; | |
| 45 | time_t emitl(); | |
| 46 | ||
| 47 | if (strlen(str) != 25) | |
| 48 | str[25] = 0; | |
| 49 | strcpy(dbuf, str); | |
| 50 | dbuf[E_MONTH+3] = 0; | |
| 36783b71 CT |
51 | if ((then.tm_mon = lookup(&dbuf[E_MONTH])) < 0) |
| 52 | return (-1); | |
| 6e1fe29b BJ |
53 | then.tm_mday = atoi(&dbuf[E_DAY]); |
| 54 | then.tm_hour = atoi(&dbuf[E_HOUR]); | |
| 55 | then.tm_min = atoi(&dbuf[E_MINUTE]); | |
| 56 | then.tm_sec = atoi(&dbuf[E_SECOND]); | |
| 57 | then.tm_year = atoi(&dbuf[E_YEAR]) - 1900; | |
| 58 | return(emitl(&then)); | |
| 59 | } | |
| 60 | ||
| 61 | static char months[] = | |
| 62 | "JanFebMarAprMayJunJulAugSepOctNovDec"; | |
| 63 | ||
| 36783b71 | 64 | static int |
| 6e1fe29b BJ |
65 | lookup(str) |
| 66 | char *str; | |
| 67 | { | |
| 68 | register char *cp, *cp2; | |
| 69 | ||
| 70 | for (cp = months, cp2 = str; *cp != 0; cp += 3) | |
| 71 | if (strncmp(cp, cp2, 3) == 0) | |
| 72 | return((cp-months) / 3); | |
| 73 | return(-1); | |
| 74 | } | |
| 75 | /* | |
| 76 | * Routine to convert a localtime(3) format date back into | |
| 77 | * a system format date. | |
| 78 | * | |
| 79 | * Use a binary search. | |
| 80 | */ | |
| 81 | ||
| 82 | struct tm *localtime(); | |
| 36783b71 | 83 | static int dcmp(); |
| 6e1fe29b | 84 | |
| 36783b71 CT |
85 | time_t |
| 86 | emitl(dp) | |
| 6e1fe29b BJ |
87 | struct tm *dp; |
| 88 | { | |
| 89 | time_t conv; | |
| 90 | register int i, bit; | |
| 91 | struct tm dcopy; | |
| 92 | ||
| 93 | dcopy = *dp; | |
| 94 | dp = &dcopy; | |
| 95 | conv = 0; | |
| 50953c5b | 96 | for (i = 30; i >= 0; i--) { |
| 6e1fe29b BJ |
97 | bit = 1 << i; |
| 98 | conv |= bit; | |
| 99 | if (dcmp(localtime(&conv), dp) > 0) | |
| 100 | conv &= ~bit; | |
| 101 | } | |
| 102 | return(conv); | |
| 103 | } | |
| 104 | ||
| 105 | /* | |
| 106 | * Compare two localtime dates, return result. | |
| 107 | */ | |
| 108 | ||
| 109 | #define DECIDE(a) \ | |
| 110 | if (dp->a > dp2->a) \ | |
| 111 | return(1); \ | |
| 112 | if (dp->a < dp2->a) \ | |
| 113 | return(-1) | |
| 114 | ||
| 36783b71 | 115 | static int |
| 6e1fe29b BJ |
116 | dcmp(dp, dp2) |
| 117 | register struct tm *dp, *dp2; | |
| 118 | { | |
| 119 | ||
| 120 | DECIDE(tm_year); | |
| 121 | DECIDE(tm_mon); | |
| 122 | DECIDE(tm_mday); | |
| 123 | DECIDE(tm_hour); | |
| 124 | DECIDE(tm_min); | |
| 125 | DECIDE(tm_sec); | |
| 126 | return(0); | |
| 127 | } |