projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 6e1fe29b BJ |
1 | static char *sccsid = "@(#)unctime.c 1.1 (Berkeley) %G%"; |
| 2 | #include <sys/types.h> | |
| 3 | #include <time.h> | |
| 4 | /* | |
| 5 | * Convert a ctime(3) format string into a system format date. | |
| 6 | * Return the date thus calculated. | |
| 7 | * | |
| 8 | * Return -1 if the string is not in ctime format. | |
| 9 | */ | |
| 10 | ||
| 11 | /* | |
| 12 | * Offsets into the ctime string to various parts. | |
| 13 | */ | |
| 14 | ||
| 15 | #define E_MONTH 4 | |
| 16 | #define E_DAY 8 | |
| 17 | #define E_HOUR 11 | |
| 18 | #define E_MINUTE 14 | |
| 19 | #define E_SECOND 17 | |
| 20 | #define E_YEAR 20 | |
| 21 | ||
| 22 | time_t unctime(str) | |
| 23 | char *str; | |
| 24 | { | |
| 25 | struct tm then; | |
| 26 | char dbuf[30]; | |
| 27 | time_t emitl(); | |
| 28 | ||
| 29 | if (strlen(str) != 25) | |
| 30 | str[25] = 0; | |
| 31 | strcpy(dbuf, str); | |
| 32 | dbuf[E_MONTH+3] = 0; | |
| 33 | if ( (then.tm_mon = lookup(&dbuf[E_MONTH])) < 0) | |
| 34 | return(-1);; | |
| 35 | then.tm_mday = atoi(&dbuf[E_DAY]); | |
| 36 | then.tm_hour = atoi(&dbuf[E_HOUR]); | |
| 37 | then.tm_min = atoi(&dbuf[E_MINUTE]); | |
| 38 | then.tm_sec = atoi(&dbuf[E_SECOND]); | |
| 39 | then.tm_year = atoi(&dbuf[E_YEAR]) - 1900; | |
| 40 | return(emitl(&then)); | |
| 41 | } | |
| 42 | ||
| 43 | static char months[] = | |
| 44 | "JanFebMarAprMayJunJulAugSepOctNovDec"; | |
| 45 | ||
| 46 | static | |
| 47 | lookup(str) | |
| 48 | char *str; | |
| 49 | { | |
| 50 | register char *cp, *cp2; | |
| 51 | ||
| 52 | for (cp = months, cp2 = str; *cp != 0; cp += 3) | |
| 53 | if (strncmp(cp, cp2, 3) == 0) | |
| 54 | return((cp-months) / 3); | |
| 55 | return(-1); | |
| 56 | } | |
| 57 | /* | |
| 58 | * Routine to convert a localtime(3) format date back into | |
| 59 | * a system format date. | |
| 60 | * | |
| 61 | * Use a binary search. | |
| 62 | */ | |
| 63 | ||
| 64 | struct tm *localtime(); | |
| 65 | ||
| 66 | time_t emitl(dp) | |
| 67 | struct tm *dp; | |
| 68 | { | |
| 69 | time_t conv; | |
| 70 | register int i, bit; | |
| 71 | struct tm dcopy; | |
| 72 | ||
| 73 | dcopy = *dp; | |
| 74 | dp = &dcopy; | |
| 75 | conv = 0; | |
| 76 | for (i = 31; i >= 0; i--) { | |
| 77 | bit = 1 << i; | |
| 78 | conv |= bit; | |
| 79 | if (dcmp(localtime(&conv), dp) > 0) | |
| 80 | conv &= ~bit; | |
| 81 | } | |
| 82 | return(conv); | |
| 83 | } | |
| 84 | ||
| 85 | /* | |
| 86 | * Compare two localtime dates, return result. | |
| 87 | */ | |
| 88 | ||
| 89 | #define DECIDE(a) \ | |
| 90 | if (dp->a > dp2->a) \ | |
| 91 | return(1); \ | |
| 92 | if (dp->a < dp2->a) \ | |
| 93 | return(-1) | |
| 94 | ||
| 95 | static | |
| 96 | dcmp(dp, dp2) | |
| 97 | register struct tm *dp, *dp2; | |
| 98 | { | |
| 99 | ||
| 100 | DECIDE(tm_year); | |
| 101 | DECIDE(tm_mon); | |
| 102 | DECIDE(tm_mday); | |
| 103 | DECIDE(tm_hour); | |
| 104 | DECIDE(tm_min); | |
| 105 | DECIDE(tm_sec); | |
| 106 | return(0); | |
| 107 | } |