xref: /freebsd/lib/libc/stdtime/timelocal.c (revision 380a989b3223d455375b4fae70fd0b9bdd43bafb)
1 /*-
2  * Copyright (c) 1997 FreeBSD Inc.
3  * 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  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  *	$Id: timelocal.c,v 1.1 1997/08/09 15:43:57 joerg Exp $
27  */
28 
29 #include <sys/types.h>
30 #include <sys/stat.h>
31 #include <sys/syslimits.h>
32 #include <fcntl.h>
33 #include <locale.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include "setlocale.h"
37 #include "timelocal.h"
38 
39 struct lc_time_T _time_localebuf;
40 int _time_using_locale;
41 
42 const struct lc_time_T	_C_time_locale = {
43 	{
44 		"Jan", "Feb", "Mar", "Apr", "May", "Jun",
45 		"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
46 	}, {
47 		"January", "February", "March", "April", "May", "June",
48 		"July", "August", "September", "October", "November", "December"
49 	}, {
50 		"Sun", "Mon", "Tue", "Wed",
51 		"Thu", "Fri", "Sat"
52 	}, {
53 		"Sunday", "Monday", "Tuesday", "Wednesday",
54 		"Thursday", "Friday", "Saturday"
55 	},
56 
57 	/* X_fmt */
58 	"%H:%M:%S",
59 
60 	/*
61 	** x_fmt
62 	** Since the C language standard calls for
63 	** "date, using locale's date format," anything goes.
64 	** Using just numbers (as here) makes Quakers happier;
65 	** it's also compatible with SVR4.
66 	*/
67 	"%m/%d/%y",
68 
69 	/*
70 	** c_fmt (ctime-compatible)
71 	** Note that
72 	**	"%a %b %d %H:%M:%S %Y"
73 	** is used by Solaris 2.3.
74 	*/
75 	"%a %b %e %X %Y",
76 
77 	/* am */
78 	"AM",
79 
80 	/* pm */
81 	"PM",
82 
83 	/* date_fmt */
84 	"%a %b %e %X %Z %Y"
85 };
86 
87 
88 int
89 __time_load_locale(const char *name)
90 {
91 	static char *		locale_buf;
92 	static char		locale_buf_C[] = "C";
93 
94 	int			fd;
95 	char *			lbuf;
96 	char *			p;
97 	const char **		ap;
98 	const char *		plim;
99 	char                    filename[PATH_MAX];
100 	struct stat		st;
101 	size_t			namesize;
102 	size_t			bufsize;
103 	int                     save_using_locale;
104 
105 	save_using_locale = _time_using_locale;
106 	_time_using_locale = 0;
107 
108 	if (name == NULL)
109 		goto no_locale;
110 
111 	if (!strcmp(name, "C") || !strcmp(name, "POSIX"))
112 		return 0;
113 
114 	/*
115 	** If the locale name is the same as our cache, use the cache.
116 	*/
117 	lbuf = locale_buf;
118 	if (lbuf != NULL && strcmp(name, lbuf) == 0) {
119 		p = lbuf;
120 		for (ap = (const char **) &_time_localebuf;
121 			ap < (const char **) (&_time_localebuf + 1);
122 				++ap)
123 					*ap = p += strlen(p) + 1;
124 		_time_using_locale = 1;
125 		return 0;
126 	}
127 	/*
128 	** Slurp the locale file into the cache.
129 	*/
130 	namesize = strlen(name) + 1;
131 
132 	if (!_PathLocale)
133 		goto no_locale;
134 	/* Range checking not needed, 'name' size is limited */
135 	strcpy(filename, _PathLocale);
136 	strcat(filename, "/");
137 	strcat(filename, name);
138 	strcat(filename, "/LC_TIME");
139 	fd = open(filename, O_RDONLY);
140 	if (fd < 0)
141 		goto no_locale;
142 	if (fstat(fd, &st) != 0)
143 		goto bad_locale;
144 	if (st.st_size <= 0)
145 		goto bad_locale;
146 	bufsize = namesize + st.st_size;
147 	locale_buf = NULL;
148 	lbuf = (lbuf == NULL || lbuf == locale_buf_C) ?
149 		malloc(bufsize) : reallocf(lbuf, bufsize);
150 	if (lbuf == NULL)
151 		goto bad_locale;
152 	(void) strcpy(lbuf, name);
153 	p = lbuf + namesize;
154 	plim = p + st.st_size;
155 	if (read(fd, p, (size_t) st.st_size) != st.st_size)
156 		goto bad_lbuf;
157 	if (close(fd) != 0)
158 		goto bad_lbuf;
159 	/*
160 	** Parse the locale file into localebuf.
161 	*/
162 	if (plim[-1] != '\n')
163 		goto bad_lbuf;
164 	for (ap = (const char **) &_time_localebuf;
165 		ap < (const char **) (&_time_localebuf + 1);
166 			++ap) {
167 				if (p == plim)
168 					goto reset_locale;
169 				*ap = p;
170 				while (*p != '\n')
171 					++p;
172 				*p++ = '\0';
173 	}
174 	/*
175 	** Record the successful parse in the cache.
176 	*/
177 	locale_buf = lbuf;
178 
179 	_time_using_locale = 1;
180 	return 0;
181 
182 reset_locale:
183 	/*
184 	 * XXX - This may not be the correct thing to do in this case.
185 	 * setlocale() assumes that we left the old locale alone.
186 	 */
187 	locale_buf = locale_buf_C;
188 	_time_localebuf = _C_time_locale;
189 	save_using_locale = 0;
190 bad_lbuf:
191 	free(lbuf);
192 bad_locale:
193 	(void) close(fd);
194 no_locale:
195 	_time_using_locale = save_using_locale;
196 	return -1;
197 }
198