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 |
| 76797561 DF |
8 | static char sccsid[] = "@(#)unctime.c 5.1 (Berkeley) %G%"; |
| 9 | #endif not lint | |
| bbbe213d | 10 | |
| 6e1fe29b | 11 | #include <sys/types.h> |
| 56140c8b | 12 | #include <sys/time.h> |
| 50953c5b | 13 | #include <stdio.h> |
| 6e1fe29b BJ |
14 | /* |
| 15 | * Convert a ctime(3) format string into a system format date. | |
| 16 | * Return the date thus calculated. | |
| 17 | * | |
| 18 | * Return -1 if the string is not in ctime format. | |
| 19 | */ | |
| 20 | ||
| 21 | /* | |
| 22 | * Offsets into the ctime string to various parts. | |
| 23 | */ | |
| 24 | ||
| 25 | #define E_MONTH 4 | |
| 26 | #define E_DAY 8 | |
| 27 | #define E_HOUR 11 | |
| 28 | #define E_MINUTE 14 | |
| 29 | #define E_SECOND 17 | |
| 30 | #define E_YEAR 20 | |
| 31 | ||
| 32 | time_t unctime(str) | |
| 33 | char *str; | |
| 34 | { | |
| 35 | struct tm then; | |
| 36 | char dbuf[30]; | |
| 37 | time_t emitl(); | |
| 38 | ||
| 39 | if (strlen(str) != 25) | |
| 40 | str[25] = 0; | |
| 41 | strcpy(dbuf, str); | |
| 42 | dbuf[E_MONTH+3] = 0; | |
| 50953c5b | 43 | if ( (then.tm_mon = lookup(&dbuf[E_MONTH])) < 0) { |
| 6e1fe29b | 44 | return(-1);; |
| 50953c5b | 45 | } |
| 6e1fe29b BJ |
46 | then.tm_mday = atoi(&dbuf[E_DAY]); |
| 47 | then.tm_hour = atoi(&dbuf[E_HOUR]); | |
| 48 | then.tm_min = atoi(&dbuf[E_MINUTE]); | |
| 49 | then.tm_sec = atoi(&dbuf[E_SECOND]); | |
| 50 | then.tm_year = atoi(&dbuf[E_YEAR]) - 1900; | |
| 51 | return(emitl(&then)); | |
| 52 | } | |
| 53 | ||
| 54 | static char months[] = | |
| 55 | "JanFebMarAprMayJunJulAugSepOctNovDec"; | |
| 56 | ||
| 57 | static | |
| 58 | lookup(str) | |
| 59 | char *str; | |
| 60 | { | |
| 61 | register char *cp, *cp2; | |
| 62 | ||
| 63 | for (cp = months, cp2 = str; *cp != 0; cp += 3) | |
| 64 | if (strncmp(cp, cp2, 3) == 0) | |
| 65 | return((cp-months) / 3); | |
| 66 | return(-1); | |
| 67 | } | |
| 68 | /* | |
| 69 | * Routine to convert a localtime(3) format date back into | |
| 70 | * a system format date. | |
| 71 | * | |
| 72 | * Use a binary search. | |
| 73 | */ | |
| 74 | ||
| 75 | struct tm *localtime(); | |
| 76 | ||
| 77 | time_t emitl(dp) | |
| 78 | struct tm *dp; | |
| 79 | { | |
| 80 | time_t conv; | |
| 81 | register int i, bit; | |
| 82 | struct tm dcopy; | |
| 83 | ||
| 84 | dcopy = *dp; | |
| 85 | dp = &dcopy; | |
| 86 | conv = 0; | |
| 50953c5b | 87 | for (i = 30; i >= 0; i--) { |
| 6e1fe29b BJ |
88 | bit = 1 << i; |
| 89 | conv |= bit; | |
| 90 | if (dcmp(localtime(&conv), dp) > 0) | |
| 91 | conv &= ~bit; | |
| 92 | } | |
| 93 | return(conv); | |
| 94 | } | |
| 95 | ||
| 96 | /* | |
| 97 | * Compare two localtime dates, return result. | |
| 98 | */ | |
| 99 | ||
| 100 | #define DECIDE(a) \ | |
| 101 | if (dp->a > dp2->a) \ | |
| 102 | return(1); \ | |
| 103 | if (dp->a < dp2->a) \ | |
| 104 | return(-1) | |
| 105 | ||
| 106 | static | |
| 107 | dcmp(dp, dp2) | |
| 108 | register struct tm *dp, *dp2; | |
| 109 | { | |
| 110 | ||
| 111 | DECIDE(tm_year); | |
| 112 | DECIDE(tm_mon); | |
| 113 | DECIDE(tm_mday); | |
| 114 | DECIDE(tm_hour); | |
| 115 | DECIDE(tm_min); | |
| 116 | DECIDE(tm_sec); | |
| 117 | return(0); | |
| 118 | } |