1 /*- 2 * Copyright (c) 1980, 1993 3 * The Regents of the University of California. 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 8.1 (Berkeley) 6/5/93"; 36 #endif /* not lint */ 37 38 #include <sys/types.h> 39 40 #include <stdio.h> 41 #include <time.h> 42 #ifdef __STDC__ 43 #include <stdlib.h> 44 #include <string.h> 45 #endif 46 47 #ifndef __P 48 #include <sys/cdefs.h> 49 #endif 50 51 /* 52 * Convert a ctime(3) format string into a system format date. 53 * Return the date thus calculated. 54 * 55 * Return -1 if the string is not in ctime format. 56 */ 57 58 /* 59 * Offsets into the ctime string to various parts. 60 */ 61 62 #define E_MONTH 4 63 #define E_DAY 8 64 #define E_HOUR 11 65 #define E_MINUTE 14 66 #define E_SECOND 17 67 #define E_YEAR 20 68 69 static int dcmp __P((struct tm *, struct tm *)); 70 static time_t emitl __P((struct tm *)); 71 static int lookup __P((char *)); 72 73 74 time_t 75 unctime(str) 76 char *str; 77 { 78 struct tm then; 79 char dbuf[26]; 80 81 (void) strncpy(dbuf, str, sizeof(dbuf) - 1); 82 dbuf[sizeof(dbuf) - 1] = '\0'; 83 dbuf[E_MONTH+3] = '\0'; 84 if ((then.tm_mon = lookup(&dbuf[E_MONTH])) < 0) 85 return (-1); 86 then.tm_mday = atoi(&dbuf[E_DAY]); 87 then.tm_hour = atoi(&dbuf[E_HOUR]); 88 then.tm_min = atoi(&dbuf[E_MINUTE]); 89 then.tm_sec = atoi(&dbuf[E_SECOND]); 90 then.tm_year = atoi(&dbuf[E_YEAR]) - 1900; 91 return(emitl(&then)); 92 } 93 94 static char months[] = 95 "JanFebMarAprMayJunJulAugSepOctNovDec"; 96 97 static int 98 lookup(str) 99 char *str; 100 { 101 register char *cp, *cp2; 102 103 for (cp = months, cp2 = str; *cp != '\0'; cp += 3) 104 if (strncmp(cp, cp2, 3) == 0) 105 return((cp-months) / 3); 106 return(-1); 107 } 108 /* 109 * Routine to convert a localtime(3) format date back into 110 * a system format date. 111 * 112 * Use a binary search. 113 */ 114 115 static time_t 116 emitl(dp) 117 struct tm *dp; 118 { 119 time_t conv; 120 register int i, bit; 121 struct tm dcopy; 122 123 dcopy = *dp; 124 dp = &dcopy; 125 conv = 0; 126 for (i = 30; i >= 0; i--) { 127 bit = 1 << i; 128 conv |= bit; 129 if (dcmp(localtime(&conv), dp) > 0) 130 conv &= ~bit; 131 } 132 return(conv); 133 } 134 135 /* 136 * Compare two localtime dates, return result. 137 */ 138 139 #define DECIDE(a) \ 140 if (dp->a > dp2->a) \ 141 return(1); \ 142 if (dp->a < dp2->a) \ 143 return(-1) 144 145 static int 146 dcmp(dp, dp2) 147 register struct tm *dp, *dp2; 148 { 149 150 DECIDE(tm_year); 151 DECIDE(tm_mon); 152 DECIDE(tm_mday); 153 DECIDE(tm_hour); 154 DECIDE(tm_min); 155 DECIDE(tm_sec); 156 return(0); 157 } 158