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
46struct strlong {
47    char* s;
48    long l;
49    };
50
51
52static void
53pound_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
71static int
72strlong_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
97static int
98scan_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
136static int
137scan_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
185static int
186is_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(). */
193static time_t
194tm_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
220time_t
221tdate_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