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 *
ct_numb(char * cp,int n,char pad)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 *
__posix_asctime_r(const struct tm * t,char * cbuf)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 *
asctime_r(const struct tm * t,char * cbuf,int buflen)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 *
ctime(const time_t * t)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 *
asctime(const struct tm * t)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