day.c revision 13840 
1/*
2 * Copyright (c) 1989, 1993, 1994
3 *	The Regents of the University of California.  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 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34
35#include <stdio.h>
36#include <sys/types.h>
37#include <time.h>
38#include <sys/uio.h>
39#include <string.h>
40#include <stdlib.h>
41
42#include "pathnames.h"
43#include "calendar.h"
44
45struct tm *tp;
46int *cumdays, offset, yrdays;
47char dayname[10];
48
49
50/* 1-based month, 0-based days, cumulative */
51int daytab[][14] = {
52	{ 0, -1, 30, 58, 89, 119, 150, 180, 211, 242, 272, 303, 333, 364 },
53	{ 0, -1, 30, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
54};
55
56static char *days[] = {
57	"sun", "mon", "tue", "wed", "thu", "fri", "sat", NULL,
58};
59
60static char *months[] = {
61	"jan", "feb", "mar", "apr", "may", "jun",
62	"jul", "aug", "sep", "oct", "nov", "dec", NULL,
63};
64
65
66
67
68void
69settime(now)
70    	time_t now;
71{
72
73	tp = localtime(&now);
74	if ( isleap(tp->tm_year + 1900) ) {
75		yrdays = 366;
76		cumdays = daytab[1];
77	} else {
78		yrdays = 365;
79		cumdays = daytab[0];
80	}
81	/* Friday displays Monday's events */
82	offset = tp->tm_wday == 5 ? 3 : 1;
83	header[5].iov_base = dayname;
84	header[5].iov_len = strftime(dayname, sizeof(dayname), "%A", tp);
85}
86
87/* convert Day[/Month][/Year] into unix time (since 1970)
88 * Day: tow digits, Month: two digits, Year: digits
89 */
90time_t Mktime (date)
91    char *date;
92{
93    time_t t;
94    int len;
95    struct tm tm;
96
97    (void)time(&t);
98    tp = localtime(&t);
99
100    len = strlen(date);
101    tm.tm_sec = 0;
102    tm.tm_min = 0;
103    tm.tm_hour = 0;
104    tm.tm_mday = tp->tm_mday;
105    tm.tm_mon = tp->tm_mon;
106    tm.tm_year = tp->tm_year;
107
108
109    /* day */
110    *(date+2) = NULL;
111    tm.tm_mday = atoi(date);
112
113    /* month */
114    if (len >= 4) {
115	*(date+5) = NULL;
116	tm.tm_mon = atoi(date+3) - 1;
117    }
118
119    /* Year */
120    if (len >= 7) {
121	tm.tm_year = atoi(date+6);
122
123	/* tm_year up 1900 ... */
124	if (tm.tm_year > 1900)
125	    tm.tm_year -= 1900;
126    }
127
128#if DEBUG
129    printf("Mktime: %d %d %d %s\n", (int)mktime(&tm), (int)t, len,
130	   asctime(&tm));
131#endif
132    return(mktime(&tm));
133}
134
135/*
136 * Possible date formats include any combination of:
137 *	3-charmonth			(January, Jan, Jan)
138 *	3-charweekday			(Friday, Monday, mon.)
139 *	numeric month or day		(1, 2, 04)
140 *
141 * Any character may separate them, or they may not be separated.  Any line,
142 * following a line that is matched, that starts with "whitespace", is shown
143 * along with the matched line.
144 */
145int
146isnow(endp)
147	char *endp;
148{
149	int day, flags, month, v1, v2;
150
151	/*
152	 * CONVENTION
153	 *
154	 * Month:     1-12
155	 * Monthname: Jan .. Dec
156	 * Day:       1-31
157	 * Weekday:   Mon-Sun
158	 *
159	 */
160
161	flags = 0;
162
163	/* read first field */
164	/* didn't recognize anything, skip it */
165	if (!(v1 = getfield(endp, &endp, &flags)))
166		return (0);
167
168	/* Easter or Easter depending days */
169	if (flags & F_EASTER)
170	    day = v1;
171
172	 /*
173	  * 1. {Weekday,Day} XYZ ...
174	  *
175	  *    where Day is > 12
176	  */
177	else if (flags & F_ISDAY || v1 > 12) {
178
179		/* found a day; day: 1-31 or weekday: 1-7 */
180		day = v1;
181
182		/* {Day,Weekday} {Month,Monthname} ... */
183		/* if no recognizable month, assume just a day alone
184		 * in other words, find month or use current month */
185		if (!(month = getfield(endp, &endp, &flags)))
186			month = tp->tm_mon + 1;
187	}
188
189	/* 2. {Monthname} XYZ ... */
190	else if (flags & F_ISMONTH) {
191		month = v1;
192
193		/* Monthname {day,weekday} */
194		/* if no recognizable day, assume the first day in month */
195		if (!(day = getfield(endp, &endp, &flags)))
196			day = 1;
197	}
198
199	/* Hm ... */
200	else {
201		v2 = getfield(endp, &endp, &flags);
202
203		/*
204		 * {Day} {Monthname} ...
205		 * where Day <= 12
206		 */
207		if (flags & F_ISMONTH) {
208			day = v1;
209			month = v2;
210		}
211
212		/* {Month} {Weekday,Day} ...  */
213		else {
214			/* F_ISDAY set, v2 > 12, or no way to tell */
215			month = v1;
216			/* if no recognizable day, assume the first */
217			day = v2 ? v2 : 1;
218		}
219	}
220
221	/* convert Weekday into *next*  Day,
222	 * e.g.: 'Sunday' -> 22
223	 *       'SunayLast' -> ??
224	 */
225	if (flags & F_ISDAY) {
226#if DEBUG
227	    fprintf(stderr, "\nday: %d %s month %d\n", day, endp, month);
228#endif
229
230	    /* variable weekday, SundayLast, MondayFirst ... */
231	    if (day < 0 || day >= 10) {
232
233		/* negative offset; last, -4 .. -1 */
234		if (day < 0) {
235		    v1 = day/10 - 1;          /* offset -4 ... -1 */
236	            day = 10 + (day % 10);    /* day 1 ... 7 */
237
238		    /* day, eg '22th' */
239		    v2 = tp->tm_mday + (((day - 1) - tp->tm_wday + 7) % 7);
240
241		    /* (month length - day) / 7 + 1 */
242		    if (((int)((cumdays[month+1] -
243		               cumdays[month] - v2) / 7) + 1) == -v1)
244			/* bingo ! */
245			day = v2;
246
247		    /* set to yesterday */
248		    else
249			day = tp->tm_mday - 1;
250		}
251
252		/* first, second ... +1 ... +5 */
253		else {
254		    v1 = day/10;        /* offset: +1 (first Sunday) ... */
255		    day = day % 10;
256
257		    /* day, eg '22th' */
258		    v2 = tp->tm_mday + (((day - 1) - tp->tm_wday + 7) % 7);
259
260		    /* Hurrah! matched */
261		    if ( ((v2 - 1 + 7) / 7) == v1 )
262			day = v2;
263
264		    /* set to yesterday */
265		    else
266			day = tp->tm_mday - 1;
267		}
268	    }
269
270	    /* wired */
271	    else {
272		day = tp->tm_mday + (((day - 1) - tp->tm_wday + 7) % 7);
273	    }
274	}
275
276#if DEBUG
277	fprintf(stderr, "day2: yday %d %d\n", day, tp->tm_yday);
278#endif
279	if (!(flags & F_EASTER))
280	    day = cumdays[month] + day;
281
282	/* if today or today + offset days */
283	if (day >= tp->tm_yday - f_dayBefore &&
284	    day <= tp->tm_yday + offset + f_dayAfter)
285		return (1);
286
287	/* if number of days left in this year + days to event in next year */
288	if (yrdays - tp->tm_yday + day <= offset + f_dayAfter ||
289	    /* a year backward, eg. 6 Jan and 10 days before -> 27. Dec */
290	    tp->tm_yday + day - f_dayBefore < 0
291	    )
292		return (1);
293	return (0);
294}
295
296
297int
298getmonth(s)
299	register char *s;
300{
301	register char **p;
302
303	for (p = months; *p; ++p)
304		if (!strncasecmp(s, *p, 3))
305			return ((p - months) + 1);
306	return (0);
307}
308
309
310int
311getday(s)
312	register char *s;
313{
314	register char **p;
315
316	for (p = days; *p; ++p)
317		if (!strncasecmp(s, *p, 3))
318			return ((p - days) + 1);
319	return (0);
320}
321
322/* return offset for variable weekdays
323 * -1 -> last weekday in month
324 * +1 -> first weekday in month
325 * ... etc ...
326 */
327int
328getdayvar(s)
329	register char *s;
330{
331	register int offset;
332
333
334	offset = strlen(s);
335
336
337	/* Sun+1 or Wednesday-2
338	 *    ^              ^   */
339
340	/* printf ("x: %s %s %d\n", s, s + offset - 2, offset); */
341	switch(*(s + offset - 2)) {
342	case '-':
343	    return(-(atoi(s + offset - 1)));
344	    break;
345	case '+':
346	    return(atoi(s + offset - 1));
347	    break;
348	}
349
350
351	/*
352	 * some aliases: last, first, second, third, fourth
353	 */
354
355	/* last */
356	if      (offset > 4 && !strcasecmp(s + offset - 4, "last"))
357	    return(-1);
358	else if (offset > 5 && !strcasecmp(s + offset - 5, "first"))
359	    return(+1);
360	else if (offset > 6 && !strcasecmp(s + offset - 6, "second"))
361	    return(+2);
362	else if (offset > 5 && !strcasecmp(s + offset - 5, "third"))
363	    return(+3);
364	else if (offset > 6 && !strcasecmp(s + offset - 6, "fourth"))
365	    return(+4);
366
367
368	/* no offset detected */
369	return(0);
370}
371