1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 /* Copyright (c) 1988 AT&T */ 28 /* All Rights Reserved */ 29 30 /* 31 * This routine converts time as follows. 32 * The epoch is 0000 Jan 1 1970 GMT. 33 * The argument time is in seconds since then. 34 * The localtime(t) entry returns a pointer to an array 35 * containing 36 * seconds (0-59) 37 * minutes (0-59) 38 * hours (0-23) 39 * day of month (1-31) 40 * month (0-11) 41 * year-1970 42 * weekday (0-6, Sun is 0) 43 * day of the year 44 * daylight savings flag 45 * 46 * The routine corrects for daylight saving 47 * time and will work in any time zone provided 48 * "timezone" is adjusted to the difference between 49 * Greenwich and local standard time (measured in seconds). 50 * In places like Michigan "daylight" must 51 * be initialized to 0 to prevent the conversion 52 * to daylight time. 53 * There is a table which accounts for the peculiarities 54 * undergone by daylight time in 1974-1975. 55 * 56 * The routine does not work 57 * in Saudi Arabia which runs on Solar time. 58 * 59 * asctime(tvec) 60 * where tvec is produced by localtime 61 * returns a ptr to a character string 62 * that has the ascii time in the form 63 * Thu Jan 01 00:00:00 1970\n\0 64 * 01234567890123456789012345 65 * 0 1 2 66 * 67 * ctime(t) just calls localtime, then asctime. 68 * 69 * tzset() looks for an environment variable named 70 * TZ. 71 * If the variable is present, it will set the external 72 * variables "timezone", "altzone", "daylight", and "tzname" 73 * appropriately. It is called by localtime, and 74 * may also be called explicitly by the user. 75 */ 76 77 #include "lint.h" 78 #include <mtlib.h> 79 #include <sys/types.h> 80 #include <time.h> 81 #include <errno.h> 82 #include <thread.h> 83 #include <synch.h> 84 #include "libc.h" 85 #include "tsd.h" 86 87 #define dysize(A) (((A)%4)? 365: 366) 88 #define CBUFSIZ 26 89 90 static char * 91 ct_numb(char *cp, int n, char pad) 92 { 93 cp++; 94 if (n >= 10) 95 *cp++ = (n / 10) % 10 + '0'; 96 else 97 *cp++ = pad; 98 *cp++ = n % 10 + '0'; 99 return (cp); 100 } 101 102 /* 103 * POSIX.1c standard version of the function asctime_r. 104 * User gets it via static asctime_r from the header file. 105 */ 106 char * 107 __posix_asctime_r(const struct tm *t, char *cbuf) 108 { 109 char *cp; 110 const char *ncp; 111 const char *Date = "Day Mon 00 00:00:00 YYYY\n"; 112 const char *Day = "SunMonTueWedThuFriSat"; 113 const char *Month = "JanFebMarAprMayJunJulAugSepOctNovDec"; 114 115 int year = t->tm_year + 1900; 116 117 cp = cbuf; 118 for (ncp = Date; (*cp++ = *ncp++) != '\0'; /* */) 119 ; 120 ncp = Day + (3 * t->tm_wday); 121 cp = cbuf; 122 *cp++ = *ncp++; 123 *cp++ = *ncp++; 124 *cp++ = *ncp++; 125 cp++; 126 ncp = Month + (3 * t->tm_mon); 127 *cp++ = *ncp++; 128 *cp++ = *ncp++; 129 *cp++ = *ncp++; 130 cp = ct_numb(cp, t->tm_mday, ' '); 131 cp = ct_numb(cp, t->tm_hour, '0'); 132 cp = ct_numb(cp, t->tm_min, '0'); 133 cp = ct_numb(cp, t->tm_sec, '0'); 134 135 if (year < 0 || year >= 10000) { 136 /* Only positive, 4-digit years are supported */ 137 errno = EOVERFLOW; 138 return (NULL); 139 } 140 cp = ct_numb(cp, year / 100, '0'); 141 cp--; 142 (void) ct_numb(cp, year, '0'); 143 return (cbuf); 144 } 145 146 /* 147 * POSIX.1c Draft-6 version of the function asctime_r. 148 * It was implemented by Solaris 2.3. 149 */ 150 char * 151 asctime_r(const struct tm *t, char *cbuf, int buflen) 152 { 153 if (buflen < CBUFSIZ) { 154 errno = ERANGE; 155 return (NULL); 156 } 157 return (__posix_asctime_r(t, cbuf)); 158 } 159 160 char * 161 ctime(const time_t *t) 162 { 163 char *cbuf = tsdalloc(_T_CTIME, CBUFSIZ, NULL); 164 struct tm *p; 165 166 if (cbuf == NULL) 167 return (NULL); 168 p = localtime(t); 169 if (p == NULL) 170 return (NULL); 171 return (__posix_asctime_r(p, cbuf)); 172 } 173 174 char * 175 asctime(const struct tm *t) 176 { 177 char *cbuf = tsdalloc(_T_CTIME, CBUFSIZ, NULL); 178 179 if (cbuf == NULL) 180 return (NULL); 181 return (__posix_asctime_r(t, cbuf)); 182 } 183