strptime.c revision 48614 
1/*
2 * Powerdog Industries kindly requests feedback from anyone modifying
3 * this function:
4 *
5 * Date: Thu, 05 Jun 1997 23:17:17 -0400
6 * From: Kevin Ruddy <kevin.ruddy@powerdog.com>
7 * To: James FitzGibbon <james@nexis.net>
8 * Subject: Re: Use of your strptime(3) code (fwd)
9 *
10 * The reason for the "no mod" clause was so that modifications would
11 * come back and we could integrate them and reissue so that a wider
12 * audience could use it (thereby spreading the wealth).  This has
13 * made it possible to get strptime to work on many operating systems.
14 * I'm not sure why that's "plain unacceptable" to the FreeBSD team.
15 *
16 * Anyway, you can change it to "with or without modification" as
17 * you see fit.  Enjoy.
18 *
19 * Kevin Ruddy
20 * Powerdog Industries, Inc.
21 */
22/*
23 * Copyright (c) 1994 Powerdog Industries.  All rights reserved.
24 *
25 * Redistribution and use in source and binary forms, with or without
26 * modification, are permitted provided that the following conditions
27 * are met:
28 * 1. Redistributions of source code must retain the above copyright
29 *    notice, this list of conditions and the following disclaimer.
30 * 2. Redistributions in binary form must reproduce the above copyright
31 *    notice, this list of conditions and the following disclaimer
32 *    in the documentation and/or other materials provided with the
33 *    distribution.
34 * 3. All advertising materials mentioning features or use of this
35 *    software must display the following acknowledgement:
36 *      This product includes software developed by Powerdog Industries.
37 * 4. The name of Powerdog Industries may not be used to endorse or
38 *    promote products derived from this software without specific prior
39 *    written permission.
40 *
41 * THIS SOFTWARE IS PROVIDED BY POWERDOG INDUSTRIES ``AS IS'' AND ANY
42 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
44 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE POWERDOG INDUSTRIES BE
45 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
46 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
47 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
48 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
49 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
50 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
51 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
52 */
53
54#ifdef LIBC_RCS
55static const char rcsid[] =
56	"$Id: strptime.c,v 1.6 1999/04/25 07:28:39 wes Exp $";
57#endif
58
59#ifndef lint
60#ifndef NOID
61static char copyright[] =
62"@(#) Copyright (c) 1994 Powerdog Industries.  All rights reserved.";
63static char sccsid[] = "@(#)strptime.c	0.1 (Powerdog) 94/03/27";
64#endif /* !defined NOID */
65#endif /* not lint */
66
67#include <time.h>
68#include <ctype.h>
69#include <string.h>
70#ifdef	_THREAD_SAFE
71#include <pthread.h>
72#include "pthread_private.h"
73#endif
74#include "timelocal.h"
75
76static char * _strptime(const char *, const char *, struct tm *);
77
78#ifdef	_THREAD_SAFE
79static struct pthread_mutex	_gotgmt_mutexd = PTHREAD_MUTEX_STATIC_INITIALIZER;
80static pthread_mutex_t		gotgmt_mutex   = &_gotgmt_mutexd;
81#endif
82static int got_GMT;
83
84#define asizeof(a)	(sizeof (a) / sizeof ((a)[0]))
85
86static char *
87_strptime(const char *buf, const char *fmt, struct tm *tm)
88{
89	char	c;
90	const char *ptr;
91	int	i,
92		len;
93
94	ptr = fmt;
95	while (*ptr != 0) {
96		if (*buf == 0)
97			break;
98
99		c = *ptr++;
100
101		if (c != '%') {
102			if (isspace((unsigned char)c))
103				while (*buf != 0 && isspace((unsigned char)*buf))
104					buf++;
105			else if (c != *buf++)
106				return 0;
107			continue;
108		}
109
110		c = *ptr++;
111		switch (c) {
112		case 0:
113		case '%':
114			if (*buf++ != '%')
115				return 0;
116			break;
117
118		case 'C':
119			buf = _strptime(buf, Locale->date_fmt, tm);
120			if (buf == 0)
121				return 0;
122			break;
123
124		case 'c':
125			buf = _strptime(buf, "%x %X", tm);
126			if (buf == 0)
127				return 0;
128			break;
129
130		case 'D':
131			buf = _strptime(buf, "%m/%d/%y", tm);
132			if (buf == 0)
133				return 0;
134			break;
135
136		case 'R':
137			buf = _strptime(buf, "%H:%M", tm);
138			if (buf == 0)
139				return 0;
140			break;
141
142		case 'r':
143			buf = _strptime(buf, "%I:%M:%S %p", tm);
144			if (buf == 0)
145				return 0;
146			break;
147
148		case 'T':
149			buf = _strptime(buf, "%H:%M:%S", tm);
150			if (buf == 0)
151				return 0;
152			break;
153
154		case 'X':
155			buf = _strptime(buf, Locale->X_fmt, tm);
156			if (buf == 0)
157				return 0;
158			break;
159
160		case 'x':
161			buf = _strptime(buf, Locale->x_fmt, tm);
162			if (buf == 0)
163				return 0;
164			break;
165
166		case 'j':
167			if (!isdigit((unsigned char)*buf))
168				return 0;
169
170			for (i = 0; *buf != 0 && isdigit((unsigned char)*buf); buf++) {
171				i *= 10;
172				i += *buf - '0';
173			}
174			if (i > 365)
175				return 0;
176
177			tm->tm_yday = i;
178			break;
179
180		case 'M':
181		case 'S':
182			if (*buf == 0 || isspace((unsigned char)*buf))
183				break;
184
185			if (!isdigit((unsigned char)*buf))
186				return 0;
187
188			for (i = 0; *buf != 0 && isdigit((unsigned char)*buf); buf++) {
189				i *= 10;
190				i += *buf - '0';
191			}
192			if (i > 59)
193				return 0;
194
195			if (c == 'M')
196				tm->tm_min = i;
197			else
198				tm->tm_sec = i;
199
200			if (*buf != 0 && isspace((unsigned char)*buf))
201				while (*ptr != 0 && !isspace((unsigned char)*ptr))
202					ptr++;
203			break;
204
205		case 'H':
206		case 'I':
207		case 'k':
208		case 'l':
209			if (!isdigit((unsigned char)*buf))
210				return 0;
211
212			for (i = 0; *buf != 0 && isdigit((unsigned char)*buf); buf++) {
213				i *= 10;
214				i += *buf - '0';
215			}
216			if (c == 'H' || c == 'k') {
217				if (i > 23)
218					return 0;
219			} else if (i > 11)
220				return 0;
221
222			tm->tm_hour = i;
223
224			if (*buf != 0 && isspace((unsigned char)*buf))
225				while (*ptr != 0 && !isspace((unsigned char)*ptr))
226					ptr++;
227			break;
228
229		case 'p':
230			len = strlen(Locale->am);
231			if (strncasecmp(buf, Locale->am, len) == 0) {
232				if (tm->tm_hour > 12)
233					return 0;
234				if (tm->tm_hour == 12)
235					tm->tm_hour = 0;
236				buf += len;
237				break;
238			}
239
240			len = strlen(Locale->pm);
241			if (strncasecmp(buf, Locale->pm, len) == 0) {
242				if (tm->tm_hour > 12)
243					return 0;
244				if (tm->tm_hour != 12)
245					tm->tm_hour += 12;
246				buf += len;
247				break;
248			}
249
250			return 0;
251
252		case 'A':
253		case 'a':
254			for (i = 0; i < asizeof(Locale->weekday); i++) {
255				len = strlen(Locale->weekday[i]);
256				if (strncasecmp(buf,
257						Locale->weekday[i],
258						len) == 0)
259					break;
260
261				len = strlen(Locale->wday[i]);
262				if (strncasecmp(buf,
263						Locale->wday[i],
264						len) == 0)
265					break;
266			}
267			if (i == asizeof(Locale->weekday))
268				return 0;
269
270			tm->tm_wday = i;
271			buf += len;
272			break;
273
274		case 'd':
275		case 'e':
276			if (!isdigit((unsigned char)*buf))
277				return 0;
278
279			for (i = 0; *buf != 0 && isdigit((unsigned char)*buf); buf++) {
280				i *= 10;
281				i += *buf - '0';
282			}
283			if (i > 31)
284				return 0;
285
286			tm->tm_mday = i;
287
288			if (*buf != 0 && isspace((unsigned char)*buf))
289				while (*ptr != 0 && !isspace((unsigned char)*ptr))
290					ptr++;
291			break;
292
293		case 'B':
294		case 'b':
295		case 'h':
296			for (i = 0; i < asizeof(Locale->month); i++) {
297				len = strlen(Locale->month[i]);
298				if (strncasecmp(buf,
299						Locale->month[i],
300						len) == 0)
301					break;
302
303				len = strlen(Locale->mon[i]);
304				if (strncasecmp(buf,
305						Locale->mon[i],
306						len) == 0)
307					break;
308			}
309			if (i == asizeof(Locale->month))
310				return 0;
311
312			tm->tm_mon = i;
313			buf += len;
314			break;
315
316		case 'm':
317			if (!isdigit((unsigned char)*buf))
318				return 0;
319
320			for (i = 0; *buf != 0 && isdigit((unsigned char)*buf); buf++) {
321				i *= 10;
322				i += *buf - '0';
323			}
324			if (i < 1 || i > 12)
325				return 0;
326
327			tm->tm_mon = i - 1;
328
329			if (*buf != 0 && isspace((unsigned char)*buf))
330				while (*ptr != 0 && !isspace((unsigned char)*ptr))
331					ptr++;
332			break;
333
334		case 'Y':
335		case 'y':
336			if (*buf == 0 || isspace((unsigned char)*buf))
337				break;
338
339			if (!isdigit((unsigned char)*buf))
340				return 0;
341
342			for (i = 0; *buf != 0 && isdigit((unsigned char)*buf); buf++) {
343				i *= 10;
344				i += *buf - '0';
345			}
346			if (c == 'Y')
347				i -= 1900;
348			if (c == 'y' && i < 69)
349				i += 100;
350			if (i < 0)
351				return 0;
352
353			tm->tm_year = i;
354
355			if (*buf != 0 && isspace((unsigned char)*buf))
356				while (*ptr != 0 && !isspace((unsigned char)*ptr))
357					ptr++;
358			break;
359
360		case 'Z':
361			{
362			const char *cp;
363			char *zonestr;
364
365			for (cp = buf; *cp && isupper(*cp); ++cp) {/*empty*/}
366			if (cp - buf) {
367				zonestr = alloca(cp - buf + 1);
368				strncpy(zonestr, buf, cp - buf);
369				zonestr[cp - buf] = '\0';
370				tzset();
371				if (0 == strcmp(zonestr, "GMT")) {
372				    got_GMT = 1;
373				} else if (0 == strcmp(zonestr, tzname[0])) {
374				    tm->tm_isdst = 0;
375				} else if (0 == strcmp(zonestr, tzname[1])) {
376				    tm->tm_isdst = 1;
377				} else {
378				    return 0;
379				}
380				buf += cp - buf;
381			}
382			}
383			break;
384		}
385	}
386	return (char *)buf;
387}
388
389
390char *
391strptime(const char *buf, const char *fmt, struct tm *tm)
392{
393	char *ret;
394
395#ifdef	_THREAD_SAFE
396	pthread_mutex_lock(&gotgmt_mutex);
397#endif
398
399	got_GMT = 0;
400	ret = _strptime(buf, fmt, tm);
401	if (ret && got_GMT) {
402		time_t t = timegm(tm);
403	    localtime_r(&t, tm);
404		got_GMT = 0;
405	}
406
407#ifdef	_THREAD_SAFE
408	pthread_mutex_unlock(&gotgmt_mutex);
409#endif
410
411	return ret;
412}
413