asctime.c revision 15923 
1/*-
2 * Copyright (c) 1990, 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 *	$Id:$
34 */
35
36#ifndef lint
37#ifndef NOID
38static char	elsieid[] = "@(#)asctime.c	7.5";
39#endif /* !defined NOID */
40#endif /* !defined lint */
41
42/*LINTLIBRARY*/
43
44#include "private.h"
45#include "tzfile.h"
46
47/*
48** A la X3J11, with core dump avoidance.
49*/
50
51char *
52asctime(timeptr)
53register const struct tm *	timeptr;
54{
55	static const char	wday_name[][3] = {
56		"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
57	};
58	static const char	mon_name[][3] = {
59		"Jan", "Feb", "Mar", "Apr", "May", "Jun",
60		"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
61	};
62	/*
63	** Big enough for something such as
64	** ??? ???-2147483648 -2147483648:-2147483648:-2147483648 -2147483648\n
65	** (two three-character abbreviations, five strings denoting integers,
66	** three explicit spaces, two explicit colons, a newline,
67	** and a trailing ASCII nul).
68	*/
69	static char		result[3 * 2 + 5 * INT_STRLEN_MAXIMUM(int) +
70					3 + 2 + 1 + 1];
71	register const char *	wn;
72	register const char *	mn;
73
74	if (timeptr->tm_wday < 0 || timeptr->tm_wday >= DAYSPERWEEK)
75		wn = "???";
76	else	wn = wday_name[timeptr->tm_wday];
77	if (timeptr->tm_mon < 0 || timeptr->tm_mon >= MONSPERYEAR)
78		mn = "???";
79	else	mn = mon_name[timeptr->tm_mon];
80	/*
81	** The X3J11-suggested format is
82	**	"%.3s %.3s%3d %02.2d:%02.2d:%02.2d %d\n"
83	** Since the .2 in 02.2d is ignored, we drop it.
84	*/
85	(void) sprintf(result, "%.3s %.3s%3d %02d:%02d:%02d %d\n",
86		wn, mn,
87		timeptr->tm_mday, timeptr->tm_hour,
88		timeptr->tm_min, timeptr->tm_sec,
89		TM_YEAR_BASE + timeptr->tm_year);
90	return result;
91}
92