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 <time.h> 81 #include <sys/types.h> 82 #include <errno.h> 83 #include <thread.h> 84 #include <synch.h> 85 #include <mtlib.h> 86 #include "libc.h" 87 88 89 /* 90 * POSIX.1c Draft-6 version of the function ctime_r. 91 * It was implemented by Solaris 2.3. 92 */ 93 char * 94 ctime_r(const time_t *t, char *buffer, int buflen) 95 { 96 struct tm res; 97 98 if (localtime_r(t, &res) == NULL) 99 return (NULL); 100 101 if (asctime_r(&res, buffer, buflen) == NULL) 102 return (NULL); 103 104 return (buffer); 105 } 106 107 /* 108 * POSIX.1c standard version of the function ctime_r. 109 * User gets it via static ctime_r from the header file. 110 */ 111 char * 112 __posix_ctime_r(const time_t *t, char *buffer) 113 { 114 struct tm res; 115 116 if (localtime_r(t, &res) == NULL) 117 return (NULL); 118 119 if (__posix_asctime_r(&res, buffer) == NULL) 120 return (NULL); 121 122 return (buffer); 123 } 124