projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| bbbe213d SL |
1 | #ifndef lint |
| 2 | static char sccsid[] = "@(#)unctime.c 1.5 (Berkeley) %G%"; | |
| 3 | #endif | |
| 4 | ||
| 6e1fe29b | 5 | #include <sys/types.h> |
| 56140c8b | 6 | #include <sys/time.h> |
| 50953c5b | 7 | #include <stdio.h> |
| 6e1fe29b BJ |
8 | /* |
| 9 | * Convert a ctime(3) format string into a system format date. | |
| 10 | * Return the date thus calculated. | |
| 11 | * | |
| 12 | * Return -1 if the string is not in ctime format. | |
| 13 | */ | |
| 14 | ||
| 15 | /* | |
| 16 | * Offsets into the ctime string to various parts. | |
| 17 | */ | |
| 18 | ||
| 19 | #define E_MONTH 4 | |
| 20 | #define E_DAY 8 | |
| 21 | #define E_HOUR 11 | |
| 22 | #define E_MINUTE 14 | |
| 23 | #define E_SECOND 17 | |
| 24 | #define E_YEAR 20 | |
| 25 | ||
| 26 | time_t unctime(str) | |
| 27 | char *str; | |
| 28 | { | |
| 29 | struct tm then; | |
| 30 | char dbuf[30]; | |
| 31 | time_t emitl(); | |
| 32 | ||
| 33 | if (strlen(str) != 25) | |
| 34 | str[25] = 0; | |
| 35 | strcpy(dbuf, str); | |
| 36 | dbuf[E_MONTH+3] = 0; | |
| 50953c5b | 37 | if ( (then.tm_mon = lookup(&dbuf[E_MONTH])) < 0) { |
| 6e1fe29b | 38 | return(-1);; |
| 50953c5b | 39 | } |
| 6e1fe29b BJ |
40 | then.tm_mday = atoi(&dbuf[E_DAY]); |
| 41 | then.tm_hour = atoi(&dbuf[E_HOUR]); | |
| 42 | then.tm_min = atoi(&dbuf[E_MINUTE]); | |
| 43 | then.tm_sec = atoi(&dbuf[E_SECOND]); | |
| 44 | then.tm_year = atoi(&dbuf[E_YEAR]) - 1900; | |
| 45 | return(emitl(&then)); | |
| 46 | } | |
| 47 | ||
| 48 | static char months[] = | |
| 49 | "JanFebMarAprMayJunJulAugSepOctNovDec"; | |
| 50 | ||
| 51 | static | |
| 52 | lookup(str) | |
| 53 | char *str; | |
| 54 | { | |
| 55 | register char *cp, *cp2; | |
| 56 | ||
| 57 | for (cp = months, cp2 = str; *cp != 0; cp += 3) | |
| 58 | if (strncmp(cp, cp2, 3) == 0) | |
| 59 | return((cp-months) / 3); | |
| 60 | return(-1); | |
| 61 | } | |
| 62 | /* | |
| 63 | * Routine to convert a localtime(3) format date back into | |
| 64 | * a system format date. | |
| 65 | * | |
| 66 | * Use a binary search. | |
| 67 | */ | |
| 68 | ||
| 69 | struct tm *localtime(); | |
| 70 | ||
| 71 | time_t emitl(dp) | |
| 72 | struct tm *dp; | |
| 73 | { | |
| 74 | time_t conv; | |
| 75 | register int i, bit; | |
| 76 | struct tm dcopy; | |
| 77 | ||
| 78 | dcopy = *dp; | |
| 79 | dp = &dcopy; | |
| 80 | conv = 0; | |
| 50953c5b | 81 | for (i = 30; i >= 0; i--) { |
| 6e1fe29b BJ |
82 | bit = 1 << i; |
| 83 | conv |= bit; | |
| 84 | if (dcmp(localtime(&conv), dp) > 0) | |
| 85 | conv &= ~bit; | |
| 86 | } | |
| 87 | return(conv); | |
| 88 | } | |
| 89 | ||
| 90 | /* | |
| 91 | * Compare two localtime dates, return result. | |
| 92 | */ | |
| 93 | ||
| 94 | #define DECIDE(a) \ | |
| 95 | if (dp->a > dp2->a) \ | |
| 96 | return(1); \ | |
| 97 | if (dp->a < dp2->a) \ | |
| 98 | return(-1) | |
| 99 | ||
| 100 | static | |
| 101 | dcmp(dp, dp2) | |
| 102 | register struct tm *dp, *dp2; | |
| 103 | { | |
| 104 | ||
| 105 | DECIDE(tm_year); | |
| 106 | DECIDE(tm_mon); | |
| 107 | DECIDE(tm_mday); | |
| 108 | DECIDE(tm_hour); | |
| 109 | DECIDE(tm_min); | |
| 110 | DECIDE(tm_sec); | |
| 111 | return(0); | |
| 112 | } |