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