xref: /onnv-gate/usr/src/lib/libc/port/gen/cftime.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*	Copyright (c) 1988 AT&T	*/
23*0Sstevel@tonic-gate /*	  All Rights Reserved  	*/
24*0Sstevel@tonic-gate 
25*0Sstevel@tonic-gate 
26*0Sstevel@tonic-gate /*
27*0Sstevel@tonic-gate  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
28*0Sstevel@tonic-gate  * Use is subject to license terms.
29*0Sstevel@tonic-gate  */
30*0Sstevel@tonic-gate 
31*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"	/* SVr4.0 1.15	*/
32*0Sstevel@tonic-gate 
33*0Sstevel@tonic-gate /*
34*0Sstevel@tonic-gate  * This routine converts time as follows.  The epoch is 0000  Jan  1
35*0Sstevel@tonic-gate  * 1970  GMT.   The  argument  time  is  in seconds since then.  The
36*0Sstevel@tonic-gate  * localtime(t) entry returns a pointer to an array containing:
37*0Sstevel@tonic-gate  *
38*0Sstevel@tonic-gate  *		  seconds (0-59)
39*0Sstevel@tonic-gate  *		  minutes (0-59)
40*0Sstevel@tonic-gate  *		  hours (0-23)
41*0Sstevel@tonic-gate  *		  day of month (1-31)
42*0Sstevel@tonic-gate  *		  month (0-11)
43*0Sstevel@tonic-gate  *		  year
44*0Sstevel@tonic-gate  *		  weekday (0-6, Sun is 0)
45*0Sstevel@tonic-gate  *		  day of the year
46*0Sstevel@tonic-gate  *		  daylight savings flag
47*0Sstevel@tonic-gate  *
48*0Sstevel@tonic-gate  * The routine corrects for daylight saving time and  will  work  in
49*0Sstevel@tonic-gate  * any  time  zone provided "timezone" is adjusted to the difference
50*0Sstevel@tonic-gate  * between Greenwich and local standard time (measured in seconds).
51*0Sstevel@tonic-gate  *
52*0Sstevel@tonic-gate  *	 ascftime(buf, format, t)	-> where t is produced by localtime
53*0Sstevel@tonic-gate  *				           and returns a ptr to a character
54*0Sstevel@tonic-gate  *				           string that has the ascii time in
55*0Sstevel@tonic-gate  *				           the format specified by the format
56*0Sstevel@tonic-gate  *				           argument (see date(1) for format
57*0Sstevel@tonic-gate  *				           syntax).
58*0Sstevel@tonic-gate  *
59*0Sstevel@tonic-gate  *	 cftime(buf, format, t) 	-> just calls ascftime.
60*0Sstevel@tonic-gate  *
61*0Sstevel@tonic-gate  *
62*0Sstevel@tonic-gate  *
63*0Sstevel@tonic-gate  */
64*0Sstevel@tonic-gate 
65*0Sstevel@tonic-gate #pragma weak ascftime = _ascftime
66*0Sstevel@tonic-gate #pragma weak cftime = _cftime
67*0Sstevel@tonic-gate 
68*0Sstevel@tonic-gate #include	"synonyms.h"
69*0Sstevel@tonic-gate #include	<mtlib.h>
70*0Sstevel@tonic-gate #include	<stddef.h>
71*0Sstevel@tonic-gate #include	<time.h>
72*0Sstevel@tonic-gate #include	<limits.h>
73*0Sstevel@tonic-gate #include	<stdlib.h>
74*0Sstevel@tonic-gate #include	<thread.h>
75*0Sstevel@tonic-gate #include	<synch.h>
76*0Sstevel@tonic-gate 
77*0Sstevel@tonic-gate int
78*0Sstevel@tonic-gate cftime(char *buf, char *format, const time_t *t)
79*0Sstevel@tonic-gate {
80*0Sstevel@tonic-gate 	struct tm res;
81*0Sstevel@tonic-gate 	struct tm *p;
82*0Sstevel@tonic-gate 
83*0Sstevel@tonic-gate 	p = localtime_r(t, &res);
84*0Sstevel@tonic-gate 	if (p == NULL) {
85*0Sstevel@tonic-gate 		*buf = '\0';
86*0Sstevel@tonic-gate 		return (0);
87*0Sstevel@tonic-gate 	}
88*0Sstevel@tonic-gate 	/* LINTED do not use ascftime() */
89*0Sstevel@tonic-gate 	return (ascftime(buf, format, p));
90*0Sstevel@tonic-gate }
91*0Sstevel@tonic-gate 
92*0Sstevel@tonic-gate int
93*0Sstevel@tonic-gate ascftime(char *buf, const char *format, const struct tm *tm)
94*0Sstevel@tonic-gate {
95*0Sstevel@tonic-gate 	/* Set format string, if not already set */
96*0Sstevel@tonic-gate 	if (format == NULL || *format == '\0')
97*0Sstevel@tonic-gate 		if (((format = getenv("CFTIME")) == 0) || *format == 0)
98*0Sstevel@tonic-gate 			format =  "%C";
99*0Sstevel@tonic-gate 
100*0Sstevel@tonic-gate 	return ((int)strftime(buf, LONG_MAX, format, tm));
101*0Sstevel@tonic-gate }
102