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 #pragma ident "%Z%%M% %I% %E% SMI" 31 32 /* 33 * This routine converts time as follows. 34 * The epoch is 0000 Jan 1 1970 GMT. 35 * The argument time is in seconds since then. 36 * The localtime(t) entry returns a pointer to an array 37 * containing 38 * seconds (0-59) 39 * minutes (0-59) 40 * hours (0-23) 41 * day of month (1-31) 42 * month (0-11) 43 * year-1970 44 * weekday (0-6, Sun is 0) 45 * day of the year 46 * daylight savings flag 47 * 48 * The routine corrects for daylight saving 49 * time and will work in any time zone provided 50 * "timezone" is adjusted to the difference between 51 * Greenwich and local standard time (measured in seconds). 52 * In places like Michigan "daylight" must 53 * be initialized to 0 to prevent the conversion 54 * to daylight time. 55 * There is a table which accounts for the peculiarities 56 * undergone by daylight time in 1974-1975. 57 * 58 * The routine does not work 59 * in Saudi Arabia which runs on Solar time. 60 * 61 * asctime(tvec) 62 * where tvec is produced by localtime 63 * returns a ptr to a character string 64 * that has the ascii time in the form 65 * Thu Jan 01 00:00:00 1970\n\0 66 * 01234567890123456789012345 67 * 0 1 2 68 * 69 * ctime(t) just calls localtime, then asctime. 70 * 71 * tzset() looks for an environment variable named 72 * TZ. 73 * If the variable is present, it will set the external 74 * variables "timezone", "altzone", "daylight", and "tzname" 75 * appropriately. It is called by localtime, and 76 * may also be called explicitly by the user. 77 */ 78 79 #include "lint.h" 80 #include <mtlib.h> 81 #include <sys/types.h> 82 #include <time.h> 83 #include <errno.h> 84 #include <thread.h> 85 #include <synch.h> 86 #include "libc.h" 87 #include "tsd.h" 88 89 #define dysize(A) (((A)%4)? 365: 366) 90 #define CBUFSIZ 26 91 92 static char * 93 ct_numb(char *cp, int n, char pad) 94 { 95 cp++; 96 if (n >= 10) 97 *cp++ = (n / 10) % 10 + '0'; 98 else 99 *cp++ = pad; 100 *cp++ = n % 10 + '0'; 101 return (cp); 102 } 103 104 /* 105 * POSIX.1c standard version of the function asctime_r. 106 * User gets it via static asctime_r from the header file. 107 */ 108 char * 109 __posix_asctime_r(const struct tm *t, char *cbuf) 110 { 111 char *cp; 112 const char *ncp; 113 const char *Date = "Day Mon 00 00:00:00 YYYY\n"; 114 const char *Day = "SunMonTueWedThuFriSat"; 115 const char *Month = "JanFebMarAprMayJunJulAugSepOctNovDec"; 116 117 int year = t->tm_year + 1900; 118 119 cp = cbuf; 120 for (ncp = Date; *cp++ = *ncp++; /* */) 121 ; 122 ncp = Day + (3 * t->tm_wday); 123 cp = cbuf; 124 *cp++ = *ncp++; 125 *cp++ = *ncp++; 126 *cp++ = *ncp++; 127 cp++; 128 ncp = Month + (3 * t->tm_mon); 129 *cp++ = *ncp++; 130 *cp++ = *ncp++; 131 *cp++ = *ncp++; 132 cp = ct_numb(cp, t->tm_mday, ' '); 133 cp = ct_numb(cp, t->tm_hour, '0'); 134 cp = ct_numb(cp, t->tm_min, '0'); 135 cp = ct_numb(cp, t->tm_sec, '0'); 136 137 if (year < 0 || year >= 10000) { 138 /* Only positive, 4-digit years are supported */ 139 errno = EOVERFLOW; 140 return (NULL); 141 } 142 cp = ct_numb(cp, year / 100, '0'); 143 cp--; 144 (void) ct_numb(cp, year, '0'); 145 return (cbuf); 146 } 147 148 /* 149 * POSIX.1c Draft-6 version of the function asctime_r. 150 * It was implemented by Solaris 2.3. 151 */ 152 char * 153 asctime_r(const struct tm *t, char *cbuf, int buflen) 154 { 155 if (buflen < CBUFSIZ) { 156 errno = ERANGE; 157 return (NULL); 158 } 159 return (__posix_asctime_r(t, cbuf)); 160 } 161 162 char * 163 ctime(const time_t *t) 164 { 165 char *cbuf = tsdalloc(_T_CTIME, CBUFSIZ, NULL); 166 struct tm *p; 167 168 if (cbuf == NULL) 169 return (NULL); 170 p = localtime(t); 171 if (p == NULL) 172 return (NULL); 173 return (__posix_asctime_r(p, cbuf)); 174 } 175 176 char * 177 asctime(const struct tm *t) 178 { 179 char *cbuf = tsdalloc(_T_CTIME, CBUFSIZ, NULL); 180 181 if (cbuf == NULL) 182 return (NULL); 183 return (__posix_asctime_r(t, cbuf)); 184 } 185