ncal.c revision 191330 
1/*-
2 * Copyright (c) 1997 Wolfgang Helbig
3 * 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 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#ifndef lint
28static const char rcsid[] =
29  "$FreeBSD: head/usr.bin/ncal/ncal.c 191330 2009-04-20 18:19:38Z rdivacky $";
30#endif /* not lint */
31
32#include <calendar.h>
33#include <ctype.h>
34#include <err.h>
35#include <langinfo.h>
36#include <locale.h>
37#include <stdio.h>
38#include <stdlib.h>
39#include <string.h>
40#include <sysexits.h>
41#include <time.h>
42#include <unistd.h>
43#include <wchar.h>
44#include <wctype.h>
45#include <term.h>
46#undef lines			/* term.h defines this */
47
48/* Width of one month with backward compatibility */
49#define MONTH_WIDTH_B_J 27
50#define MONTH_WIDTH_B 20
51
52#define MONTH_WIDTH_J 24
53#define MONTH_WIDTH 18
54
55#define MAX_WIDTH 64
56
57typedef struct date date;
58
59struct monthlines {
60	wchar_t name[MAX_WIDTH + 1];
61	char lines[7][MAX_WIDTH + 1];
62	char weeks[MAX_WIDTH + 1];
63};
64
65struct weekdays {
66	wchar_t names[7][4];
67};
68
69/* The switches from Julian to Gregorian in some countries */
70static struct djswitch {
71	const char *cc;	/* Country code according to ISO 3166 */
72	const char *nm;	/* Name of country */
73	date dt;	/* Last day of Julian calendar */
74} switches[] = {
75	{"AL", "Albania",       {1912, 11, 30}},
76	{"AT", "Austria",       {1583, 10,  5}},
77	{"AU", "Australia",     {1752,  9,  2}},
78	{"BE", "Belgium",       {1582, 12, 14}},
79	{"BG", "Bulgaria",      {1916,  3, 18}},
80	{"CA", "Canada",        {1752,  9,  2}},
81	{"CH", "Switzerland",   {1655,  2, 28}},
82	{"CN", "China",         {1911, 12, 18}},
83	{"CZ", "Czech Republic",{1584,  1,  6}},
84	{"DE", "Germany",       {1700,  2, 18}},
85	{"DK", "Denmark",       {1700,  2, 18}},
86	{"ES", "Spain",         {1582, 10,  4}},
87	{"FI", "Finland",       {1753,  2, 17}},
88	{"FR", "France",        {1582, 12,  9}},
89	{"GB", "United Kingdom",{1752,  9,  2}},
90	{"GR", "Greece",        {1924,  3,  9}},
91	{"HU", "Hungary",       {1587, 10, 21}},
92	{"IS", "Iceland",       {1700, 11, 16}},
93	{"IT", "Italy",         {1582, 10,  4}},
94	{"JP", "Japan",         {1918, 12, 18}},
95	{"LI", "Lithuania",     {1918,  2,  1}},
96	{"LN", "Latin",         {9999, 05, 31}},
97	{"LU", "Luxembourg",    {1582, 12, 14}},
98	{"LV", "Latvia",        {1918,  2,  1}},
99	{"NL", "Netherlands",   {1582, 12, 14}},
100	{"NO", "Norway",        {1700,  2, 18}},
101	{"PL", "Poland",        {1582, 10,  4}},
102	{"PT", "Portugal",      {1582, 10,  4}},
103	{"RO", "Romania",       {1919,  3, 31}},
104	{"RU", "Russia",        {1918,  1, 31}},
105	{"SI", "Slovenia",      {1919,  3,  4}},
106	{"SW", "Sweden",        {1753,  2, 17}},
107	{"TR", "Turkey",        {1926, 12, 18}},
108	{"US", "United States", {1752,  9,  2}},
109	{"YU", "Yugoslavia",    {1919,  3,  4}}
110};
111
112struct djswitch *dftswitch =
113    switches + sizeof(switches) / sizeof(struct djswitch) - 2;
114    /* default switch (should be "US") */
115
116/* Table used to print day of month and week numbers */
117char daystr[] = "     1  2  3  4  5  6  7  8  9 10 11 12 13 14 15"
118		" 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31"
119		" 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47"
120		" 48 49 50 51 52 53";
121
122/* Table used to print day of year and week numbers */
123char jdaystr[] = "       1   2   3   4   5   6   7   8   9"
124		 "  10  11  12  13  14  15  16  17  18  19"
125		 "  20  21  22  23  24  25  26  27  28  29"
126		 "  30  31  32  33  34  35  36  37  38  39"
127		 "  40  41  42  43  44  45  46  47  48  49"
128		 "  50  51  52  53  54  55  56  57  58  59"
129		 "  60  61  62  63  64  65  66  67  68  69"
130		 "  70  71  72  73  74  75  76  77  78  79"
131		 "  80  81  82  83  84  85  86  87  88  89"
132		 "  90  91  92  93  94  95  96  97  98  99"
133		 " 100 101 102 103 104 105 106 107 108 109"
134		 " 110 111 112 113 114 115 116 117 118 119"
135		 " 120 121 122 123 124 125 126 127 128 129"
136		 " 130 131 132 133 134 135 136 137 138 139"
137		 " 140 141 142 143 144 145 146 147 148 149"
138		 " 150 151 152 153 154 155 156 157 158 159"
139		 " 160 161 162 163 164 165 166 167 168 169"
140		 " 170 171 172 173 174 175 176 177 178 179"
141		 " 180 181 182 183 184 185 186 187 188 189"
142		 " 190 191 192 193 194 195 196 197 198 199"
143		 " 200 201 202 203 204 205 206 207 208 209"
144		 " 210 211 212 213 214 215 216 217 218 219"
145		 " 220 221 222 223 224 225 226 227 228 229"
146		 " 230 231 232 233 234 235 236 237 238 239"
147		 " 240 241 242 243 244 245 246 247 248 249"
148		 " 250 251 252 253 254 255 256 257 258 259"
149		 " 260 261 262 263 264 265 266 267 268 269"
150		 " 270 271 272 273 274 275 276 277 278 279"
151		 " 280 281 282 283 284 285 286 287 288 289"
152		 " 290 291 292 293 294 295 296 297 298 299"
153		 " 300 301 302 303 304 305 306 307 308 309"
154		 " 310 311 312 313 314 315 316 317 318 319"
155		 " 320 321 322 323 324 325 326 327 328 329"
156		 " 330 331 332 333 334 335 336 337 338 339"
157		 " 340 341 342 343 344 345 346 347 348 349"
158		 " 350 351 352 353 354 355 356 357 358 359"
159		 " 360 361 362 363 364 365 366";
160
161int     flag_weeks;		/* user wants number of week */
162int     nswitch;		/* user defined switch date */
163int	nswitchb;		/* switch date for backward compatibility */
164const char	*term_r, *term_e;
165int	today;
166
167char   *center(char *s, char *t, int w);
168wchar_t *wcenter(wchar_t *s, wchar_t *t, int w);
169void	mkmonth(int year, int month, int jd_flag, struct monthlines * monthl);
170void    mkmonthb(int year, int month, int jd_flag, struct monthlines * monthl);
171void    mkweekdays(struct weekdays * wds);
172int     parsemonth(const char *s, int *m, int *y);
173void    printcc(void);
174void    printeaster(int year, int julian, int orthodox);
175void    printmonth(int year, int month, int jd_flag);
176void    printmonthb(int year, int month, int jd_flag);
177void    printyear(int year, int jd_flag);
178void    printyearb(int year, int jd_flag);
179int	firstday(int y, int m);
180date   *sdate(int ndays, struct date * d);
181date   *sdateb(int ndays, struct date * d);
182int     sndays(struct date * d);
183int     sndaysb(struct date * d);
184static void usage(void);
185int     weekdayb(int nd);
186
187int
188main(int argc, char *argv[])
189{
190	struct  djswitch *p, *q;	/* to search user defined switch date */
191	date	never = {10000, 1, 1};	/* outside valid range of dates */
192	date	ukswitch = {1752, 9, 2};/* switch date for Great Britain */
193	int     ch;			/* holds the option character */
194	int     m = 0;			/* month */
195	int	y = 0;			/* year */
196	int     flag_backward = 0;	/* user called cal--backward compat. */
197	int     flag_hole_year = 0;	/* user wants the whole year */
198	int	flag_julian_cal = 0;	/* user wants Julian Calendar */
199	int     flag_julian_day = 0;	/* user wants the Julian day
200					 * numbers */
201	int	flag_orthodox = 0;	/* use wants Orthodox easter */
202	int	flag_easter = 0;	/* use wants easter date */
203	char	*cp;			/* character pointer */
204	char	*flag_month = NULL;	/* requested month as string */
205	const char    *locale;		/* locale to get country code */
206	char tbuf[1024], cbuf[512], *b;
207	time_t t;
208	struct tm *tm1;
209
210	term_e = term_r = NULL;
211	today = 0;
212	if (isatty(1) && tgetent(tbuf, getenv("TERM")) == 1) {
213		date	dt;		/* handy date */
214
215		b = cbuf;
216		term_r = tgetstr("mr", &b);
217		term_e = tgetstr("me", &b);
218		t = time(NULL);
219		tm1 = localtime(&t);
220		dt.y = tm1->tm_year + 1900;
221		dt.m = tm1->tm_mon + 1;
222		dt.d = tm1->tm_mday;
223
224		today = sndaysb(&dt);
225	}
226
227	/*
228	 * Use locale to determine the country code,
229	 * and use the country code to determine the default
230	 * switchdate and date format from the switches table.
231	 */
232	if (setlocale(LC_ALL, "") == NULL)
233		warn("setlocale");
234	locale = setlocale(LC_TIME, NULL);
235	if (locale == NULL ||
236	    strcmp(locale, "C") == 0 ||
237	    strcmp(locale, "POSIX") == 0 ||
238	    strcmp(locale, "ASCII") == 0 ||
239	    strcmp(locale, "US-ASCII") == 0)
240		locale = "_US";
241	q = switches + sizeof(switches) / sizeof(struct djswitch);
242	for (p = switches; p != q; p++)
243		if ((cp = strstr(locale, p->cc)) != NULL && *(cp - 1) == '_')
244			break;
245	if (p == q) {
246		nswitch = ndaysj(&dftswitch->dt);
247	} else {
248		nswitch = ndaysj(&p->dt);
249		dftswitch = p;
250	}
251
252
253	/*
254	 * Get the filename portion of argv[0] and set flag_backward if
255	 * this program is called "cal".
256	 */
257	cp = strrchr(argv[0], '/');
258	cp = (cp == NULL) ? argv[0] : cp + 1;
259	if (strcmp("cal", cp) == 0)
260		flag_backward = 1;
261
262	/* Set the switch date to United Kingdom if backwards compatible */
263	if (flag_backward)
264		nswitchb = ndaysj(&ukswitch);
265
266	while ((ch = getopt(argc, argv, "Jejm:ops:wy")) != -1)
267		switch (ch) {
268		case 'J':
269			if (flag_backward)
270				usage();
271			nswitch = ndaysj(&never);
272			flag_julian_cal = 1;
273			break;
274		case 'e':
275			if (flag_backward)
276				usage();
277			flag_easter = 1;
278			break;
279		case 'j':
280			flag_julian_day = 1;
281			break;
282		case 'm':
283			flag_month = optarg;
284			break;
285		case 'o':
286			if (flag_backward)
287				usage();
288			flag_orthodox = 1;
289			flag_easter = 1;
290			break;
291		case 'p':
292			if (flag_backward)
293				usage();
294			printcc();
295			return (0);
296			break;
297		case 's':
298			if (flag_backward)
299				usage();
300			q = switches +
301			    sizeof(switches) / sizeof(struct djswitch);
302			for (p = switches;
303			     p != q && strcmp(p->cc, optarg) != 0; p++)
304				;
305			if (p == q)
306				errx(EX_USAGE,
307				    "%s: invalid country code", optarg);
308			nswitch = ndaysj(&(p->dt));
309			break;
310		case 'w':
311			if (flag_backward)
312				usage();
313			flag_weeks = 1;
314			break;
315		case 'y':
316			flag_hole_year = 1;
317			break;
318		default:
319			usage();
320		}
321
322	argc -= optind;
323	argv += optind;
324
325	switch (argc) {
326	case 2:
327		if (flag_easter)
328			usage();
329		flag_month = *argv++;
330		/* FALLTHROUGH */
331	case 1:
332		y = atoi(*argv++);
333		if (y < 1 || y > 9999)
334			errx(EX_USAGE, "year %d not in range 1..9999", y);
335		break;
336	case 0:
337		{
338			time_t t;
339			struct tm *tm;
340
341			t = time(NULL);
342			tm = localtime(&t);
343			y = tm->tm_year + 1900;
344			m = tm->tm_mon + 1;
345		}
346		break;
347	default:
348		usage();
349	}
350
351	if (flag_month != NULL) {
352		if (parsemonth(flag_month, &m, &y)) {
353			errx(EX_USAGE,
354			    "%s is neither a month number (1..12) nor a name",
355			    flag_month);
356		}
357	}
358
359	if (flag_easter)
360		printeaster(y, flag_julian_cal, flag_orthodox);
361	else if (argc == 1 || flag_hole_year) {
362		/* disable the highlight for now */
363		today = 0;
364		if (flag_backward)
365			printyearb(y, flag_julian_day);
366		else
367			printyear(y, flag_julian_day);
368	} else
369		if (flag_backward)
370			printmonthb(y, m, flag_julian_day);
371		else
372			printmonth(y, m, flag_julian_day);
373
374	return (0);
375}
376
377static void
378usage(void)
379{
380
381	fputs(
382	    "usage: cal [-jy] [[month] year]\n"
383	    "       cal [-j] [-m month] [year]\n"
384	    "       ncal [-Jjpwy] [-s country_code] [[month] year]\n"
385	    "       ncal [-Jeo] [year]\n", stderr);
386	exit(EX_USAGE);
387}
388
389/* print the assumed switches for all countries */
390void
391printcc(void)
392{
393	struct djswitch *p;
394	int n;	/* number of lines to print */
395	int m;	/* offset from left to right table entry on the same line */
396
397#define FSTR "%c%s %-15s%4d-%02d-%02d"
398#define DFLT(p) ((p) == dftswitch ? '*' : ' ')
399#define FSTRARG(p) DFLT(p), (p)->cc, (p)->nm, (p)->dt.y, (p)->dt.m, (p)->dt.d
400
401	n = sizeof(switches) / sizeof(struct djswitch);
402	m = (n + 1) / 2;
403	n /= 2;
404	for (p = switches; p != switches + n; p++)
405		printf(FSTR"     "FSTR"\n", FSTRARG(p), FSTRARG(p+m));
406	if (m != n)
407		printf(FSTR"\n", FSTRARG(p));
408}
409
410/* print the date of easter sunday */
411void
412printeaster(int y, int julian, int orthodox)
413{
414	date    dt;
415	struct tm tm;
416	char    buf[80];
417	static int d_first = -1;
418
419	if (d_first < 0)
420		d_first = (*nl_langinfo(D_MD_ORDER) == 'd');
421	/* force orthodox easter for years before 1583 */
422	if (y < 1583)
423		orthodox = 1;
424
425	if (orthodox)
426		if (julian)
427			easteroj(y, &dt);
428		else
429			easterog(y, &dt);
430	else
431		easterg(y, &dt);
432
433	memset(&tm, 0, sizeof(tm));
434	tm.tm_year = dt.y - 1900;
435	tm.tm_mon  = dt.m - 1;
436	tm.tm_mday = dt.d;
437	strftime(buf, sizeof(buf), d_first ? "%e %B %Y" : "%B %e %Y",  &tm);
438	printf("%s\n", buf);
439}
440
441void
442printmonth(int y, int m, int jd_flag)
443{
444	struct monthlines month;
445	struct weekdays wds;
446	int i;
447
448	mkmonth(y, m - 1, jd_flag, &month);
449	mkweekdays(&wds);
450	printf("    %ls %d\n", month.name, y);
451	for (i = 0; i != 7; i++)
452		printf("%.2ls%s\n", wds.names[i], month.lines[i]);
453	if (flag_weeks)
454		printf("  %s\n", month.weeks);
455}
456
457void
458printmonthb(int y, int m, int jd_flag)
459{
460	struct monthlines month;
461	struct weekdays wds;
462	wchar_t s[MAX_WIDTH], t[MAX_WIDTH];
463	int i;
464	int mw;
465
466	mkmonthb(y, m - 1, jd_flag, &month);
467	mkweekdays(&wds);
468
469	mw = jd_flag ? MONTH_WIDTH_B_J : MONTH_WIDTH_B;
470
471	swprintf(s, MAX_WIDTH, L"%ls %d", month.name, y);
472	wprintf(L"%ls\n", wcenter(t, s, mw));
473
474	if (jd_flag)
475		wprintf(L" %ls %ls %ls %ls %ls %ls %.2ls\n",
476			wds.names[6], wds.names[0],
477			wds.names[1], wds.names[2], wds.names[3],
478			wds.names[4], wds.names[5]);
479	else
480		wprintf(L"%ls%ls%ls%ls%ls%ls%.2ls\n", wds.names[6],
481			wds.names[0], wds.names[1], wds.names[2], wds.names[3],
482			wds.names[4], wds.names[5]);
483
484	for (i = 0; i != 6; i++)
485		printf("%s\n", month.lines[i]+1);
486}
487
488void
489printyear(int y, int jd_flag)
490{
491	struct monthlines year[12];
492	struct weekdays wds;
493	char    s[80], t[80];
494	int     i, j;
495	int     mpl;
496	int     mw;
497
498	for (i = 0; i != 12; i++)
499		mkmonth(y, i, jd_flag, year + i);
500	mkweekdays(&wds);
501	mpl = jd_flag ? 3 : 4;
502	mw = jd_flag ? MONTH_WIDTH_J : MONTH_WIDTH;
503
504	sprintf(s, "%d", y);
505	printf("%s\n", center(t, s, mpl * mw));
506
507	for (j = 0; j != 12; j += mpl) {
508		printf("    %-*ls%-*ls",
509		    mw, year[j].name,
510		    mw, year[j + 1].name);
511		if (mpl == 3)
512			printf("%ls\n", year[j + 2].name);
513		else
514			printf("%-*ls%ls\n",
515		    	    mw, year[j + 2].name,
516		    	    year[j + 3].name);
517		for (i = 0; i != 7; i++) {
518			printf("%.2ls%-*s%-*s",
519			    wds.names[i],
520			    mw, year[j].lines[i],
521			    mw, year[j + 1].lines[i]);
522			if (mpl == 3)
523				printf("%s\n", year[j + 2].lines[i]);
524			else
525				printf("%-*s%s\n",
526			    	    mw, year[j + 2].lines[i],
527			    	    year[j + 3].lines[i]);
528		}
529		if (flag_weeks) {
530			if (mpl == 3)
531				printf("  %-*s%-*s%-s\n",
532				    mw, year[j].weeks,
533				    mw, year[j + 1].weeks,
534				    year[j + 2].weeks);
535			else
536				printf("  %-*s%-*s%-*s%-s\n",
537				    mw, year[j].weeks,
538				    mw, year[j + 1].weeks,
539				    mw, year[j + 2].weeks,
540				    year[j + 3].weeks);
541		}
542	}
543}
544
545void
546printyearb(int y, int jd_flag)
547{
548	struct monthlines year[12];
549	struct weekdays wds;
550	char	s[80], t[80];
551	wchar_t	ws[80], wt[80];
552	int     i, j;
553	int     mpl;
554	int     mw;
555
556	for (i = 0; i != 12; i++)
557		mkmonthb(y, i, jd_flag, year + i);
558	mkweekdays(&wds);
559	mpl = jd_flag ? 2 : 3;
560	mw = jd_flag ? MONTH_WIDTH_B_J : MONTH_WIDTH_B;
561
562	sprintf(s, "%d", y);
563	printf("%s\n\n", center(t, s, mw * mpl + mpl));
564
565	for (j = 0; j != 12; j += mpl) {
566		printf("%-*ls  ", mw, wcenter(ws, year[j].name, mw));
567		if (mpl == 2)
568			printf("%ls\n", wcenter(ws, year[j + 1].name, mw));
569		else
570			printf("%-*ls  %ls\n", mw,
571			    wcenter(ws, year[j + 1].name, mw),
572			    wcenter(wt, year[j + 2].name, mw));
573
574		if (mpl == 2)
575			wprintf(L" %ls %ls %ls %ls %ls %ls %ls "
576				" %ls %ls %ls %ls %ls %ls %.2ls\n",
577				wds.names[6], wds.names[0], wds.names[1],
578				wds.names[2], wds.names[3], wds.names[4],
579				wds.names[5],
580				wds.names[6], wds.names[0], wds.names[1],
581				wds.names[2], wds.names[3], wds.names[4],
582				wds.names[5]);
583		else
584			wprintf(L"%ls%ls%ls%ls%ls%ls%ls "
585				"%ls%ls%ls%ls%ls%ls%ls "
586				"%ls%ls%ls%ls%ls%ls%.2ls\n",
587				wds.names[6], wds.names[0], wds.names[1],
588				wds.names[2], wds.names[3], wds.names[4],
589				wds.names[5],
590				wds.names[6], wds.names[0], wds.names[1],
591				wds.names[2], wds.names[3], wds.names[4],
592				wds.names[5],
593				wds.names[6], wds.names[0], wds.names[1],
594				wds.names[2], wds.names[3], wds.names[4],
595				wds.names[5]);
596		for (i = 0; i != 6; i++) {
597			if (mpl == 2)
598				printf("%-*s  %s\n",
599			    mw, year[j].lines[i]+1,
600			    year[j + 1].lines[i]+1);
601			else
602				printf("%-*s  %-*s  %s\n",
603			    mw, year[j].lines[i]+1,
604			    mw, year[j + 1].lines[i]+1,
605			    year[j + 2].lines[i]+1);
606
607		}
608	}
609}
610
611void
612mkmonth(int y, int m, int jd_flag, struct monthlines *mlines)
613{
614
615	struct tm tm;		/* for strftime printing local names of
616				 * months */
617	date    dt;		/* handy date */
618	int     dw;		/* width of numbers */
619	int     first;		/* first day of month */
620	int     firstm;		/* first day of first week of month */
621	int     i, j, k, l;	/* just indices */
622	int     last;		/* the first day of next month */
623	int     jan1 = 0;	/* the first day of this year */
624	char   *ds;		/* pointer to day strings (daystr or
625				 * jdaystr) */
626
627	/* Set name of month. */
628	memset(&tm, 0, sizeof(tm));
629	tm.tm_mon = m;
630	wcsftime(mlines->name, sizeof(mlines->name) / sizeof(mlines->name[0]),
631		 L"%OB", &tm);
632	mlines->name[0] = towupper(mlines->name[0]);
633
634	/*
635	 * Set first and last to the day number of the first day of this
636	 * month and the first day of next month respectively. Set jan1 to
637	 * the day number of the first day of this year.
638	 */
639	first = firstday(y, m + 1);
640	if (m == 11)
641		last = firstday(y + 1, 1);
642	else
643		last = firstday(y, m + 2);
644
645	if (jd_flag)
646		jan1 = firstday(y, 1);
647
648	/*
649	 * Set firstm to the day number of monday of the first week of
650	 * this month. (This might be in the last month)
651	 */
652	firstm = first - weekday(first);
653
654	/* Set ds (daystring) and dw (daywidth) according to the jd_flag */
655	if (jd_flag) {
656		ds = jdaystr;
657		dw = 4;
658	} else {
659		ds = daystr;
660		dw = 3;
661	}
662
663	/*
664	 * Fill the lines with day of month or day of year (julian day)
665	 * line index: i, each line is one weekday. column index: j, each
666	 * column is one day number. print column index: k.
667	 */
668	for (i = 0; i != 7; i++) {
669		l = 0;
670		for (j = firstm + i, k = 0; j < last; j += 7, k += dw) {
671			if (j == today && (term_r != NULL && term_e != NULL)) {
672				l = strlen(term_r);
673				if (jd_flag)
674					dt.d = j - jan1 + 1;
675				else
676					sdateb(j, &dt);
677				/* separator */
678				mlines->lines[i][k] = ' ';
679				/* the actual text */
680				memcpy(mlines->lines[i] + k + l,
681				    ds + dt.d * dw, dw);
682				/* highlight on */
683				memcpy(mlines->lines[i] + k + 1, term_r, l);
684				/* highlight off */
685				memcpy(mlines->lines[i] + k + l + dw, term_e,
686				    strlen(term_e));
687				l = strlen(term_e) + strlen(term_r);
688				continue;
689			}
690			if (j >= first) {
691				if (jd_flag)
692					dt.d = j - jan1 + 1;
693				else
694					sdate(j, &dt);
695				memcpy(mlines->lines[i] + k + l,
696				       ds + dt.d * dw, dw);
697			} else
698				memcpy(mlines->lines[i] + k + l, "    ", dw);
699		}
700		mlines->lines[i][k + l] = '\0';
701
702	}
703
704	/* fill the weeknumbers */
705	if (flag_weeks) {
706		for (j = firstm, k = 0; j < last;  k += dw, j += 7)
707			if (j <= nswitch)
708				memset(mlines->weeks + k, ' ', dw);
709			else
710				memcpy(mlines->weeks + k,
711				    ds + week(j, &i)*dw, dw);
712		mlines->weeks[k] = '\0';
713	}
714}
715
716void
717mkmonthb(int y, int m, int jd_flag, struct monthlines *mlines)
718{
719
720	struct tm tm;		/* for strftime printing local names of
721				 * months */
722	date    dt;		/* handy date */
723	int     dw;		/* width of numbers */
724	int     first;		/* first day of month */
725	int     firsts;		/* sunday of first week of month */
726	int     i, j, k, l;	/* just indices */
727	int     jan1 = 0;	/* the first day of this year */
728	int     last;		/* the first day of next month */
729	char   *ds;		/* pointer to day strings (daystr or
730				 * jdaystr) */
731
732	/* Set ds (daystring) and dw (daywidth) according to the jd_flag */
733	if (jd_flag) {
734		ds = jdaystr;
735		dw = 4;
736	} else {
737		ds = daystr;
738		dw = 3;
739	}
740
741	/* Set name of month centered */
742	memset(&tm, 0, sizeof(tm));
743	tm.tm_mon = m;
744	wcsftime(mlines->name, sizeof(mlines->name) / sizeof(mlines->name[0]),
745		 L"%OB", &tm);
746	mlines->name[0] = towupper(mlines->name[0]);
747
748	/*
749	 * Set first and last to the day number of the first day of this
750	 * month and the first day of next month respectively. Set jan1 to
751	 * the day number of Jan 1st of this year.
752	 */
753	dt.y = y;
754	dt.m = m + 1;
755	dt.d = 1;
756	first = sndaysb(&dt);
757	if (m == 11) {
758		dt.y = y + 1;
759		dt.m = 1;
760		dt.d = 1;
761	} else {
762		dt.y = y;
763		dt.m = m + 2;
764		dt.d = 1;
765	}
766	last = sndaysb(&dt);
767
768	if (jd_flag) {
769		dt.y = y;
770		dt.m = 1;
771		dt.d = 1;
772		jan1 = sndaysb(&dt);
773	}
774
775	/*
776	 * Set firsts to the day number of sunday of the first week of
777	 * this month. (This might be in the last month)
778	 */
779	firsts = first - (weekday(first)+1) % 7;
780
781	/*
782	 * Fill the lines with day of month or day of year (Julian day)
783	 * line index: i, each line is one week. column index: j, each
784	 * column is one day number. print column index: k.
785	 */
786	for (i = 0; i != 6; i++) {
787		l = 0;
788		for (j = firsts + 7 * i, k = 0; j < last && k != dw * 7;
789		    j++, k += dw) {
790			if (j == today && (term_r != NULL && term_e != NULL)) {
791				l = strlen(term_r);
792				if (jd_flag)
793					dt.d = j - jan1 + 1;
794				else
795					sdateb(j, &dt);
796				/* separator */
797				mlines->lines[i][k] = ' ';
798				/* the actual text */
799				memcpy(mlines->lines[i] + k + l,
800				    ds + dt.d * dw, dw);
801				/* highlight on */
802				memcpy(mlines->lines[i] + k + 1, term_r, l);
803				/* highlight off */
804				memcpy(mlines->lines[i] + k + l + dw, term_e,
805				    strlen(term_e));
806				l = strlen(term_e) + strlen(term_r);
807				continue;
808			}
809			if (j >= first) {
810				if (jd_flag)
811					dt.d = j - jan1 + 1;
812				else
813					sdateb(j, &dt);
814				memcpy(mlines->lines[i] + k + l,
815				       ds + dt.d * dw, dw);
816			} else
817				memcpy(mlines->lines[i] + k + l, "    ", dw);
818		}
819		if (k == 0)
820			mlines->lines[i][1] = '\0';
821		else
822			mlines->lines[i][k + l] = '\0';
823	}
824}
825
826/* Put the local names of weekdays into the wds */
827void
828mkweekdays(struct weekdays *wds)
829{
830	int i, len;
831	struct tm tm;
832	wchar_t buf[20];
833
834	memset(&tm, 0, sizeof(tm));
835
836	for (i = 0; i != 7; i++) {
837		tm.tm_wday = (i+1) % 7;
838		wcsftime(buf, sizeof(buf), L"%a", &tm);
839		len = wcslen(buf);
840		if (len > 2)
841			len = 2;
842		wcscpy(wds->names[i], L"   ");
843		wcsncpy(wds->names[i] + 2 - len, buf, len);
844	}
845}
846
847/*
848 * Compute the day number of the first
849 * existing date after the first day in month.
850 * (the first day in month and even the month might not exist!)
851 */
852int
853firstday(int y, int m)
854{
855	date dt;
856	int nd;
857
858	dt.y = y;
859	dt.m = m;
860	dt.d = 1;
861	nd = sndays(&dt);
862	for (;;) {
863		sdate(nd, &dt);
864		if ((dt.m >= m && dt.y == y) || dt.y > y)
865			return (nd);
866		else
867			nd++;
868	}
869	/* NEVER REACHED */
870}
871
872/*
873 * Compute the number of days from date, obey the local switch from
874 * Julian to Gregorian if specified by the user.
875 */
876int
877sndays(struct date *d)
878{
879
880	if (nswitch != 0)
881		if (nswitch < ndaysj(d))
882			return (ndaysg(d));
883		else
884			return (ndaysj(d));
885	else
886		return ndaysg(d);
887}
888
889/*
890 * Compute the number of days from date, obey the switch from
891 * Julian to Gregorian as used by UK and her colonies.
892 */
893int
894sndaysb(struct date *d)
895{
896
897	if (nswitchb < ndaysj(d))
898		return (ndaysg(d));
899	else
900		return (ndaysj(d));
901}
902
903/* Inverse of sndays */
904struct date *
905sdate(int nd, struct date *d)
906{
907
908	if (nswitch < nd)
909		return (gdate(nd, d));
910	else
911		return (jdate(nd, d));
912}
913
914/* Inverse of sndaysb */
915struct date *
916sdateb(int nd, struct date *d)
917{
918
919	if (nswitchb < nd)
920		return (gdate(nd, d));
921	else
922		return (jdate(nd, d));
923}
924
925/* Center string t in string s of length w by putting enough leading blanks */
926char *
927center(char *s, char *t, int w)
928{
929	char blanks[80];
930
931	memset(blanks, ' ', sizeof(blanks));
932	sprintf(s, "%.*s%s", (int)(w - strlen(t)) / 2, blanks, t);
933	return (s);
934}
935
936/* Center string t in string s of length w by putting enough leading blanks */
937wchar_t *
938wcenter(wchar_t *s, wchar_t *t, int w)
939{
940	char blanks[80];
941
942	memset(blanks, ' ', sizeof(blanks));
943	swprintf(s, MAX_WIDTH, L"%.*s%ls", (int)(w - wcslen(t)) / 2, blanks, t);
944	return (s);
945}
946
947int
948parsemonth(const char *s, int *m, int *y)
949{
950	int nm, ny;
951	char *cp;
952	struct tm tm;
953
954	nm = (int)strtol(s, &cp, 10);
955	if (cp != s) {
956		ny = *y;
957		if (*cp == '\0') {
958			;	/* no special action */
959		} else if (*cp == 'f' || *cp == 'F') {
960			if (nm <= *m)
961				ny++;
962		} else if (*cp == 'p' || *cp == 'P') {
963			if (nm >= *m)
964				ny--;
965		} else
966			return (1);
967		if (nm < 1 || nm > 12)
968			return 1;
969		*m = nm;
970		*y = ny;
971		return (0);
972	}
973	if (strptime(s, "%B", &tm) != NULL || strptime(s, "%b", &tm) != NULL) {
974		*m = tm.tm_mon + 1;
975		return (0);
976	}
977	return (1);
978}
979