strptime.c revision 53083 
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  "$FreeBSD: head/lib/libc/stdtime/strptime.c 53083 1999-11-10 14:40:59Z sheldonh $";
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 < 1 || i > 366)
175				return 0;
176
177			tm->tm_yday = i - 1;
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
193			if (c == 'M') {
194				if (i > 59)
195					return 0;
196				tm->tm_min = i;
197			} else {
198				if (i > 60)
199					return 0;
200				tm->tm_sec = i;
201			}
202
203			if (*buf != 0 && isspace((unsigned char)*buf))
204				while (*ptr != 0 && !isspace((unsigned char)*ptr))
205					ptr++;
206			break;
207
208		case 'H':
209		case 'I':
210		case 'k':
211		case 'l':
212			if (!isdigit((unsigned char)*buf))
213				return 0;
214
215			for (i = 0; *buf != 0 && isdigit((unsigned char)*buf); buf++) {
216				i *= 10;
217				i += *buf - '0';
218			}
219			if (c == 'H' || c == 'k') {
220				if (i > 23)
221					return 0;
222			} else if (i > 11)
223				return 0;
224
225			tm->tm_hour = i;
226
227			if (*buf != 0 && isspace((unsigned char)*buf))
228				while (*ptr != 0 && !isspace((unsigned char)*ptr))
229					ptr++;
230			break;
231
232		case 'p':
233			len = strlen(Locale->am);
234			if (strncasecmp(buf, Locale->am, len) == 0) {
235				if (tm->tm_hour > 12)
236					return 0;
237				if (tm->tm_hour == 12)
238					tm->tm_hour = 0;
239				buf += len;
240				break;
241			}
242
243			len = strlen(Locale->pm);
244			if (strncasecmp(buf, Locale->pm, len) == 0) {
245				if (tm->tm_hour > 12)
246					return 0;
247				if (tm->tm_hour != 12)
248					tm->tm_hour += 12;
249				buf += len;
250				break;
251			}
252
253			return 0;
254
255		case 'A':
256		case 'a':
257			for (i = 0; i < asizeof(Locale->weekday); i++) {
258				len = strlen(Locale->weekday[i]);
259				if (strncasecmp(buf,
260						Locale->weekday[i],
261						len) == 0)
262					break;
263
264				len = strlen(Locale->wday[i]);
265				if (strncasecmp(buf,
266						Locale->wday[i],
267						len) == 0)
268					break;
269			}
270			if (i == asizeof(Locale->weekday))
271				return 0;
272
273			tm->tm_wday = i;
274			buf += len;
275			break;
276
277		case 'U':
278		case 'W':
279			/*
280			 * XXX This is bogus, as we can not assume any valid
281			 * information present in the tm structure at this
282			 * point to calculate a real value, so just check the
283			 * range for now.
284			 */
285			if (!isdigit((unsigned char)*buf))
286				return 0;
287
288			for (i = 0; *buf != 0 && isdigit((unsigned char)*buf); buf++) {
289				i *= 10;
290				i += *buf - '0';
291			}
292			if (i > 53)
293				return 0;
294
295			if (*buf != 0 && isspace((unsigned char)*buf))
296				while (*ptr != 0 && !isspace((unsigned char)*ptr))
297					ptr++;
298			break;
299
300		case 'w':
301			if (!isdigit((unsigned char)*buf))
302				return 0;
303
304			for (i = 0; *buf != 0 && isdigit((unsigned char)*buf); buf++) {
305				i *= 10;
306				i += *buf - '0';
307			}
308			if (i > 6)
309				return 0;
310
311			tm->tm_wday = i;
312
313			if (*buf != 0 && isspace((unsigned char)*buf))
314				while (*ptr != 0 && !isspace((unsigned char)*ptr))
315					ptr++;
316			break;
317
318		case 'd':
319		case 'e':
320			if (!isdigit((unsigned char)*buf))
321				return 0;
322
323			for (i = 0; *buf != 0 && isdigit((unsigned char)*buf); buf++) {
324				i *= 10;
325				i += *buf - '0';
326			}
327			if (i > 31)
328				return 0;
329
330			tm->tm_mday = i;
331
332			if (*buf != 0 && isspace((unsigned char)*buf))
333				while (*ptr != 0 && !isspace((unsigned char)*ptr))
334					ptr++;
335			break;
336
337		case 'B':
338		case 'b':
339		case 'h':
340			for (i = 0; i < asizeof(Locale->month); i++) {
341				len = strlen(Locale->month[i]);
342				if (strncasecmp(buf,
343						Locale->month[i],
344						len) == 0)
345					break;
346
347				len = strlen(Locale->mon[i]);
348				if (strncasecmp(buf,
349						Locale->mon[i],
350						len) == 0)
351					break;
352			}
353			if (i == asizeof(Locale->month))
354				return 0;
355
356			tm->tm_mon = i;
357			buf += len;
358			break;
359
360		case 'm':
361			if (!isdigit((unsigned char)*buf))
362				return 0;
363
364			for (i = 0; *buf != 0 && isdigit((unsigned char)*buf); buf++) {
365				i *= 10;
366				i += *buf - '0';
367			}
368			if (i < 1 || i > 12)
369				return 0;
370
371			tm->tm_mon = i - 1;
372
373			if (*buf != 0 && isspace((unsigned char)*buf))
374				while (*ptr != 0 && !isspace((unsigned char)*ptr))
375					ptr++;
376			break;
377
378		case 'Y':
379		case 'y':
380			if (*buf == 0 || isspace((unsigned char)*buf))
381				break;
382
383			if (!isdigit((unsigned char)*buf))
384				return 0;
385
386			for (i = 0; *buf != 0 && isdigit((unsigned char)*buf); buf++) {
387				i *= 10;
388				i += *buf - '0';
389			}
390			if (c == 'Y')
391				i -= 1900;
392			if (c == 'y' && i < 69)
393				i += 100;
394			if (i < 0)
395				return 0;
396
397			tm->tm_year = i;
398
399			if (*buf != 0 && isspace((unsigned char)*buf))
400				while (*ptr != 0 && !isspace((unsigned char)*ptr))
401					ptr++;
402			break;
403
404		case 'Z':
405			{
406			const char *cp;
407			char *zonestr;
408
409			for (cp = buf; *cp && isupper((unsigned char)*cp); ++cp) {/*empty*/}
410			if (cp - buf) {
411				zonestr = alloca(cp - buf + 1);
412				strncpy(zonestr, buf, cp - buf);
413				zonestr[cp - buf] = '\0';
414				tzset();
415				if (0 == strcmp(zonestr, "GMT")) {
416				    got_GMT = 1;
417				} else if (0 == strcmp(zonestr, tzname[0])) {
418				    tm->tm_isdst = 0;
419				} else if (0 == strcmp(zonestr, tzname[1])) {
420				    tm->tm_isdst = 1;
421				} else {
422				    return 0;
423				}
424				buf += cp - buf;
425			}
426			}
427			break;
428		}
429	}
430	return (char *)buf;
431}
432
433
434char *
435strptime(const char *buf, const char *fmt, struct tm *tm)
436{
437	char *ret;
438
439#ifdef	_THREAD_SAFE
440	pthread_mutex_lock(&gotgmt_mutex);
441#endif
442
443	got_GMT = 0;
444	ret = _strptime(buf, fmt, tm);
445	if (ret && got_GMT) {
446		time_t t = timegm(tm);
447	    localtime_r(&t, tm);
448		got_GMT = 0;
449	}
450
451#ifdef	_THREAD_SAFE
452	pthread_mutex_unlock(&gotgmt_mutex);
453#endif
454
455	return ret;
456}
457