timelocal.c revision 53960 
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 * $FreeBSD: head/lib/libc/stdtime/timelocal.c 53960 1999-11-30 19:24:07Z ache $
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 <stddef.h>
35#include <stdlib.h>
36#include <string.h>
37#include "setlocale.h"
38#include "timelocal.h"
39
40static int split_lines(char *, const char *);
41static void set_from_buf(const char *, int);
42
43struct lc_time_T _time_localebuf;
44int _time_using_locale;
45
46#define	LCTIME_SIZE_FULL (sizeof(struct lc_time_T) / sizeof(char *))
47#define	LCTIME_SIZE_1 \
48	(offsetof(struct lc_time_T, alt_month[0]) / sizeof(char *))
49#define LCTIME_SIZE_2 \
50	(offsetof(struct lc_time_T, Ef_fmt) / sizeof(char *))
51
52const struct lc_time_T	_C_time_locale = {
53	{
54		"Jan", "Feb", "Mar", "Apr", "May", "Jun",
55		"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
56	}, {
57		"January", "February", "March", "April", "May", "June",
58		"July", "August", "September", "October", "November", "December"
59	}, {
60		"Sun", "Mon", "Tue", "Wed",
61		"Thu", "Fri", "Sat"
62	}, {
63		"Sunday", "Monday", "Tuesday", "Wednesday",
64		"Thursday", "Friday", "Saturday"
65	},
66
67	/* X_fmt */
68	"%H:%M:%S",
69
70	/*
71	** x_fmt
72	** Since the C language standard calls for
73	** "date, using locale's date format," anything goes.
74	** Using just numbers (as here) makes Quakers happier;
75	** it's also compatible with SVR4.
76	*/
77	"%m/%d/%y",
78
79	/*
80	** c_fmt (ctime-compatible)
81	** Note that
82	**	"%a %b %d %H:%M:%S %Y"
83	** is used by Solaris 2.3.
84	*/
85	"%a %Ef %X %Y",
86
87	/* am */
88	"AM",
89
90	/* pm */
91	"PM",
92
93	/* date_fmt */
94	"%a %Ef %X %Z %Y",
95
96	{
97		"January", "February", "March", "April", "May", "June",
98		"July", "August", "September", "October", "November", "December"
99	},
100
101	/* Ef_fmt
102	** To determine short months / day order
103	*/
104	"%b %e",
105
106	/* EF_fmt
107	** To determine long months / day order
108	*/
109	"%B %e"
110};
111
112
113int
114__time_load_locale(const char *name)
115{
116	static char *		locale_buf;
117	static char		locale_buf_C[] = "C";
118	static int		num_lines;
119
120	int			fd;
121	char *			lbuf;
122	char *			p;
123	const char *		plim;
124	char                    filename[PATH_MAX];
125	struct stat		st;
126	size_t			namesize;
127	size_t			bufsize;
128	int                     save_using_locale;
129
130	save_using_locale = _time_using_locale;
131	_time_using_locale = 0;
132
133	if (name == NULL)
134		goto no_locale;
135
136	if (!strcmp(name, "C") || !strcmp(name, "POSIX"))
137		return 0;
138
139	/*
140	** If the locale name is the same as our cache, use the cache.
141	*/
142	lbuf = locale_buf;
143	if (lbuf != NULL && strcmp(name, lbuf) == 0) {
144		set_from_buf(lbuf, num_lines);
145		_time_using_locale = 1;
146		return 0;
147	}
148	/*
149	** Slurp the locale file into the cache.
150	*/
151	namesize = strlen(name) + 1;
152
153	if (!_PathLocale)
154		goto no_locale;
155	/* Range checking not needed, 'name' size is limited */
156	strcpy(filename, _PathLocale);
157	strcat(filename, "/");
158	strcat(filename, name);
159	strcat(filename, "/LC_TIME");
160	fd = open(filename, O_RDONLY);
161	if (fd < 0)
162		goto no_locale;
163	if (fstat(fd, &st) != 0)
164		goto bad_locale;
165	if (st.st_size <= 0)
166		goto bad_locale;
167	bufsize = namesize + st.st_size;
168	locale_buf = NULL;
169	lbuf = (lbuf == NULL || lbuf == locale_buf_C) ?
170		malloc(bufsize) : reallocf(lbuf, bufsize);
171	if (lbuf == NULL)
172		goto bad_locale;
173	(void) strcpy(lbuf, name);
174	p = lbuf + namesize;
175	plim = p + st.st_size;
176	if (read(fd, p, (size_t) st.st_size) != st.st_size)
177		goto bad_lbuf;
178	if (close(fd) != 0)
179		goto bad_lbuf;
180	/*
181	** Parse the locale file into localebuf.
182	*/
183	if (plim[-1] != '\n')
184		goto bad_lbuf;
185	num_lines = split_lines(p, plim);
186	if (num_lines >= LCTIME_SIZE_FULL)
187		num_lines = LCTIME_SIZE_FULL;
188	else if (num_lines >= LCTIME_SIZE_2)
189		num_lines = LCTIME_SIZE_2;
190	else if (num_lines >= LCTIME_SIZE_1)
191		num_lines = LCTIME_SIZE_1;
192	else
193		goto reset_locale;
194	set_from_buf(lbuf, num_lines);
195	/*
196	** Record the successful parse in the cache.
197	*/
198	locale_buf = lbuf;
199
200	_time_using_locale = 1;
201	return 0;
202
203reset_locale:
204	/*
205	 * XXX - This may not be the correct thing to do in this case.
206	 * setlocale() assumes that we left the old locale alone.
207	 */
208	locale_buf = locale_buf_C;
209	_time_localebuf = _C_time_locale;
210	save_using_locale = 0;
211bad_lbuf:
212	free(lbuf);
213bad_locale:
214	(void) close(fd);
215no_locale:
216	_time_using_locale = save_using_locale;
217	return -1;
218}
219
220static int
221split_lines(char *p, const char *plim)
222{
223	int i;
224
225	for (i = 0; p < plim; i++) {
226		p = strchr(p, '\n');
227		*p++ = '\0';
228	}
229	return i;
230}
231
232static void
233set_from_buf(const char *p, int num_lines)
234{
235	const char **ap;
236	int i;
237
238	for (ap = (const char **) &_time_localebuf, i = 0;
239	    i < num_lines; ++ap, ++i)
240		*ap = p += strlen(p) + 1;
241	if (num_lines == LCTIME_SIZE_FULL)
242		return;
243	for (i = 0; i < 12; i++)
244		_time_localebuf.alt_month[i] = _time_localebuf.month[i];
245}
246