xref: /haiku/src/apps/poorman/libhttpd/tdate_parse.c (revision 922e7ba1f3228e6f28db69b0ded8f86eb32dea17)
1 /* tdate_parse - parse string dates into internal form, stripped-down version
2 **
3 ** Copyright © 1995 by Jef Poskanzer <jef@mail.acme.com>.
4 ** All rights reserved.
5 **
6 ** Redistribution and use in source and binary forms, with or without
7 ** modification, are permitted provided that the following conditions
8 ** are met:
9 ** 1. Redistributions of source code must retain the above copyright
10 **    notice, this list of conditions and the following disclaimer.
11 ** 2. Redistributions in binary form must reproduce the above copyright
12 **    notice, this list of conditions and the following disclaimer in the
13 **    documentation and/or other materials provided with the distribution.
14 **
15 ** THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 ** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 ** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 ** ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 ** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 ** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 ** OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 ** HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 ** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 ** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 ** SUCH DAMAGE.
26 */
27 
28 /* This is a stripped-down version of date_parse.c, available at
29 ** http://www.acme.com/software/date_parse/
30 */
31 
32 #include <sys/types.h>
33 
34 #include <ctype.h>
35 #ifdef HAVE_MEMORY_H
36 #include <memory.h>
37 #endif
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <time.h>
42 
43 #include "tdate_parse.h"
44 
45 
46 struct strlong {
47     char* s;
48     long l;
49     };
50 
51 
52 static void
53 pound_case( char* str )
54     {
55     for ( ; *str != '\0'; ++str )
56 	{
57 	if ( isupper( (int) *str ) )
58 	    *str = tolower( (int) *str );
59 	}
60     }
61 
62 //static int
63 //strlong_compare( v1, v2 )
64 //    char* v1;
65 //    char* v2;
66 //    {
67 //    return strcmp( ((struct strlong*) v1)->s, ((struct strlong*) v2)->s );
68 //    }
69 
70 
71 static int
72 strlong_search( char* str, const struct strlong* tab, int n, long* lP )
73     {
74     int i, h, l, r;
75 
76     l = 0;
77     h = n - 1;
78     for (;;)
79 	{
80 	i = ( h + l ) / 2;
81 	r = strcmp( str, tab[i].s );
82 	if ( r < 0 )
83 	    h = i - 1;
84 	else if ( r > 0 )
85 	    l = i + 1;
86 	else
87 	    {
88 	    *lP = tab[i].l;
89 	    return 1;
90 	    }
91 	if ( h < l )
92 	    return 0;
93 	}
94     }
95 
96 
97 static int
98 scan_wday( char* str_wday, long* tm_wdayP )
99     {
100 //    static struct strlong wday_tab[] = {
101 //	{ "sun", 0 }, { "sunday", 0 },
102 //	{ "mon", 1 }, { "monday", 1 },
103 //	{ "tue", 2 }, { "tuesday", 2 },
104 //	{ "wed", 3 }, { "wednesday", 3 },
105 //	{ "thu", 4 }, { "thursday", 4 },
106 //	{ "fri", 5 }, { "friday", 5 },
107 //	{ "sat", 6 }, { "saturday", 6 },
108 //	};
109 //    static int sorted = 0;
110 //
111 //    if ( ! sorted )
112 //	{
113 //	(void) qsort(
114 //	    wday_tab, sizeof(wday_tab)/sizeof(struct strlong),
115 //	    sizeof(struct strlong), strlong_compare );
116 //	sorted = 1;
117 //	}
118 
119 	/*manually sorted wday_tab to avoid concurrent accessing problem*/
120 	static const struct strlong wday_tab[] = {
121 		{ "fri", 5 }, { "friday", 5 },
122 		{ "mon", 1 }, { "monday", 1 },
123 		{ "sat", 6 }, { "saturday", 6 },
124 		{ "sun", 0 }, { "sunday", 0 },
125 		{ "thu", 4 }, { "thursday", 4 },
126 		{ "tue", 2 }, { "tuesday", 2 },
127 		{ "wed", 3 }, { "wednesday", 3 }
128 	};
129 
130     pound_case( str_wday );
131     return strlong_search(
132 	str_wday, wday_tab, sizeof(wday_tab)/sizeof(struct strlong), tm_wdayP );
133     }
134 
135 
136 static int
137 scan_mon( char* str_mon, long* tm_monP )
138     {
139 //    static struct strlong mon_tab[] = {
140 //	{ "jan", 0 }, { "january", 0 },
141 //	{ "feb", 1 }, { "february", 1 },
142 //	{ "mar", 2 }, { "march", 2 },
143 //	{ "apr", 3 }, { "april", 3 },
144 //	{ "may", 4 },
145 //	{ "jun", 5 }, { "june", 5 },
146 //	{ "jul", 6 }, { "july", 6 },
147 //	{ "aug", 7 }, { "august", 7 },
148 //	{ "sep", 8 }, { "september", 8 },
149 //	{ "oct", 9 }, { "october", 9 },
150 //	{ "nov", 10 }, { "november", 10 },
151 //	{ "dec", 11 }, { "december", 11 },
152 //	};
153 //    static int sorted = 0;
154 //
155 //    if ( ! sorted )
156 //	{
157 //	(void) qsort(
158 //	    mon_tab, sizeof(mon_tab)/sizeof(struct strlong),
159 //	    sizeof(struct strlong), strlong_compare );
160 //	sorted = 1;
161 //	}
162 
163 	/*manually sorted mon_tab to avoid concurrent accessing problem*/
164 	static const struct strlong mon_tab[] = {
165 		{ "apr", 3 }, { "april", 3 },
166 		{ "aug", 7 }, { "august", 7 },
167 		{ "dec", 11}, { "december", 11 },
168 		{ "feb", 1 }, { "february", 1 },
169 		{ "jan", 0 }, { "january", 0 },
170 		{ "jul", 6 }, { "july", 6 },
171 		{ "jun", 5 }, { "june", 5 },
172 		{ "mar", 2 }, { "march", 2 },
173 		{ "may", 4 },
174 		{ "nov", 10}, { "november", 10 },
175 		{ "oct", 9 }, { "october", 9 },
176 		{ "sep", 8 }, { "september", 8 }
177 	};
178 
179     pound_case( str_mon );
180     return strlong_search(
181 	str_mon, mon_tab, sizeof(mon_tab)/sizeof(struct strlong), tm_monP );
182     }
183 
184 
185 static int
186 is_leap( int year )
187     {
188     return year % 400? ( year % 100 ? ( year % 4 ? 0 : 1 ) : 0 ) : 1;
189     }
190 
191 
192 /* Basically the same as mktime(). */
193 static time_t
194 tm_to_time( struct tm* tmP )
195     {
196     time_t t;
197     static int monthtab[12] = {
198 	0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 };
199 
200     /* Years since epoch, converted to days. */
201     t = ( tmP->tm_year - 70 ) * 365;
202     /* Leap days for previous years. */
203     t += ( tmP->tm_year - 69 ) / 4;
204     /* Days for the beginning of this month. */
205     t += monthtab[tmP->tm_mon];
206     /* Leap day for this year. */
207     if ( tmP->tm_mon >= 2 && is_leap( tmP->tm_year + 1900 ) )
208 	++t;
209     /* Days since the beginning of this month. */
210     t += tmP->tm_mday - 1;	/* 1-based field */
211     /* Hours, minutes, and seconds. */
212     t = t * 24 + tmP->tm_hour;
213     t = t * 60 + tmP->tm_min;
214     t = t * 60 + tmP->tm_sec;
215 
216     return t;
217     }
218 
219 
220 time_t
221 tdate_parse( char* str )
222     {
223     struct tm tm;
224     char* cp;
225     char str_mon[500], str_wday[500];
226     int tm_sec, tm_min, tm_hour, tm_mday, tm_year;
227     long tm_mon, tm_wday;
228     time_t t;
229 
230     /* Initialize. */
231     (void) memset( (char*) &tm, 0, sizeof(struct tm) );
232 
233     /* Skip initial whitespace ourselves - sscanf is clumsy at this. */
234     for ( cp = str; *cp == ' ' || *cp == '\t'; ++cp )
235 	continue;
236 
237     /* And do the sscanfs.  WARNING: you can add more formats here,
238     ** but be careful!  You can easily screw up the parsing of existing
239     ** formats when you add new ones.  The order is important.
240     */
241 
242     /* DD-mth-YY HH:MM:SS GMT */
243     if ( sscanf( cp, "%d-%400[a-zA-Z]-%d %d:%d:%d GMT",
244 		&tm_mday, str_mon, &tm_year, &tm_hour, &tm_min,
245 		&tm_sec ) == 6 &&
246 	    scan_mon( str_mon, &tm_mon ) )
247 	{
248 	tm.tm_mday = tm_mday;
249 	tm.tm_mon = tm_mon;
250 	tm.tm_year = tm_year;
251 	tm.tm_hour = tm_hour;
252 	tm.tm_min = tm_min;
253 	tm.tm_sec = tm_sec;
254 	}
255 
256     /* DD mth YY HH:MM:SS GMT */
257     else if ( sscanf( cp, "%d %400[a-zA-Z] %d %d:%d:%d GMT",
258 		&tm_mday, str_mon, &tm_year, &tm_hour, &tm_min,
259 		&tm_sec) == 6 &&
260 	    scan_mon( str_mon, &tm_mon ) )
261 	{
262 	tm.tm_mday = tm_mday;
263 	tm.tm_mon = tm_mon;
264 	tm.tm_year = tm_year;
265 	tm.tm_hour = tm_hour;
266 	tm.tm_min = tm_min;
267 	tm.tm_sec = tm_sec;
268 	}
269 
270     /* HH:MM:SS GMT DD-mth-YY */
271     else if ( sscanf( cp, "%d:%d:%d GMT %d-%400[a-zA-Z]-%d",
272 		&tm_hour, &tm_min, &tm_sec, &tm_mday, str_mon,
273 		&tm_year ) == 6 &&
274 	    scan_mon( str_mon, &tm_mon ) )
275 	{
276 	tm.tm_hour = tm_hour;
277 	tm.tm_min = tm_min;
278 	tm.tm_sec = tm_sec;
279 	tm.tm_mday = tm_mday;
280 	tm.tm_mon = tm_mon;
281 	tm.tm_year = tm_year;
282 	}
283 
284     /* HH:MM:SS GMT DD mth YY */
285     else if ( sscanf( cp, "%d:%d:%d GMT %d %400[a-zA-Z] %d",
286 		&tm_hour, &tm_min, &tm_sec, &tm_mday, str_mon,
287 		&tm_year ) == 6 &&
288 	    scan_mon( str_mon, &tm_mon ) )
289 	{
290 	tm.tm_hour = tm_hour;
291 	tm.tm_min = tm_min;
292 	tm.tm_sec = tm_sec;
293 	tm.tm_mday = tm_mday;
294 	tm.tm_mon = tm_mon;
295 	tm.tm_year = tm_year;
296 	}
297 
298     /* wdy, DD-mth-YY HH:MM:SS GMT */
299     else if ( sscanf( cp, "%400[a-zA-Z], %d-%400[a-zA-Z]-%d %d:%d:%d GMT",
300 		str_wday, &tm_mday, str_mon, &tm_year, &tm_hour, &tm_min,
301 		&tm_sec ) == 7 &&
302 	    scan_wday( str_wday, &tm_wday ) &&
303 	    scan_mon( str_mon, &tm_mon ) )
304 	{
305 	tm.tm_wday = tm_wday;
306 	tm.tm_mday = tm_mday;
307 	tm.tm_mon = tm_mon;
308 	tm.tm_year = tm_year;
309 	tm.tm_hour = tm_hour;
310 	tm.tm_min = tm_min;
311 	tm.tm_sec = tm_sec;
312 	}
313 
314     /* wdy, DD mth YY HH:MM:SS GMT */
315     else if ( sscanf( cp, "%400[a-zA-Z], %d %400[a-zA-Z] %d %d:%d:%d GMT",
316 		str_wday, &tm_mday, str_mon, &tm_year, &tm_hour, &tm_min,
317 		&tm_sec ) == 7 &&
318 	    scan_wday( str_wday, &tm_wday ) &&
319 	    scan_mon( str_mon, &tm_mon ) )
320 	{
321 	tm.tm_wday = tm_wday;
322 	tm.tm_mday = tm_mday;
323 	tm.tm_mon = tm_mon;
324 	tm.tm_year = tm_year;
325 	tm.tm_hour = tm_hour;
326 	tm.tm_min = tm_min;
327 	tm.tm_sec = tm_sec;
328 	}
329 
330     /* wdy mth DD HH:MM:SS GMT YY */
331     else if ( sscanf( cp, "%400[a-zA-Z] %400[a-zA-Z] %d %d:%d:%d GMT %d",
332 		str_wday, str_mon, &tm_mday, &tm_hour, &tm_min, &tm_sec,
333 		&tm_year ) == 7 &&
334 	    scan_wday( str_wday, &tm_wday ) &&
335 	    scan_mon( str_mon, &tm_mon ) )
336 	{
337 	tm.tm_wday = tm_wday;
338 	tm.tm_mon = tm_mon;
339 	tm.tm_mday = tm_mday;
340 	tm.tm_hour = tm_hour;
341 	tm.tm_min = tm_min;
342 	tm.tm_sec = tm_sec;
343 	tm.tm_year = tm_year;
344 	}
345     else
346 	return (time_t) -1;
347 
348     if ( tm.tm_year > 1900 )
349 	tm.tm_year -= 1900;
350     else if ( tm.tm_year < 70 )
351 	tm.tm_year += 100;
352 
353     t = tm_to_time( &tm );
354 
355     return t;
356     }
357