busybox/coreutils/cal.c

/* vi: set sw=4 ts=4: */
/*
 * Calendar implementation for busybox
 *
 * See original copyright at the end of this file
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 */

/* BB_AUDIT SUSv3 compliant with -j and -y extensions (from util-linux). */
/* BB_AUDIT BUG: The output of 'cal -j 1752' is incorrect.  The upstream
 * BB_AUDIT BUG: version in util-linux seems to be broken as well. */
/* http://www.opengroup.org/onlinepubs/007904975/utilities/cal.html */

/* Mar 16, 2003      Manuel Novoa III   (mjn3@codepoet.org)
 *
 * Major size reduction... over 50% (>1.5k) on i386.
 */

#include "busybox.h"

#define	THURSDAY		4		/* for reformation */
#define	SATURDAY		6		/* 1 Jan 1 was a Saturday */

#define	FIRST_MISSING_DAY	639787		/* 3 Sep 1752 */
#define	NUMBER_MISSING_DAYS	11		/* 11 day correction */

#define	MAXDAYS			42		/* max slots in a month array */
#define	SPACE			-1		/* used in day array */

static const char days_in_month[] = {
	0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
};

static const char sep1752[] = {
		 1,	2,	14,	15,	16,
	17,	18,	19,	20,	21,	22,	23,
	24,	25,	26,	27,	28,	29,	30
};

static int julian;

/* leap year -- account for Gregorian reformation in 1752 */
#define	leap_year(yr) \
	((yr) <= 1752 ? !((yr) % 4) : \
	(!((yr) % 4) && ((yr) % 100)) || !((yr) % 400))

static int is_leap_year(int year)
{
	return leap_year(year);
}
#undef leap_year
#define leap_year(yr) is_leap_year(yr)

/* number of centuries since 1700, not inclusive */
#define	centuries_since_1700(yr) \
	((yr) > 1700 ? (yr) / 100 - 17 : 0)

/* number of centuries since 1700 whose modulo of 400 is 0 */
#define	quad_centuries_since_1700(yr) \
	((yr) > 1600 ? ((yr) - 1600) / 400 : 0)

/* number of leap years between year 1 and this year, not inclusive */
#define	leap_years_since_year_1(yr) \
	((yr) / 4 - centuries_since_1700(yr) + quad_centuries_since_1700(yr))

static void center (char *, int, int);
static void day_array (int, int, int *);
static void trim_trailing_spaces_and_print (char *);

static void blank_string(char *buf, size_t buflen);
static char *build_row(char *p, int *dp);

#define	DAY_LEN		3		/* 3 spaces per day */
#define	J_DAY_LEN	(DAY_LEN + 1)
#define	WEEK_LEN	20		/* 7 * 3 - one space at the end */
#define	J_WEEK_LEN	(WEEK_LEN + 7)
#define	HEAD_SEP	2		/* spaces between day headings */

int cal_main(int argc, char **argv)
{
	struct tm *local_time;
	struct tm zero_tm;
	time_t now;
	int month, year, flags, i;
	char *month_names[12];
	char day_headings[28];	/* 28 for julian, 21 for nonjulian */
	char buf[40];

	flags = getopt32(argc, argv, "jy");

	julian = flags & 1;

	argv += optind;

	month = 0;

	if ((argc -= optind) > 2) {
		bb_show_usage();
	}

	if (!argc) {
		time(&now);
		local_time = localtime(&now);
		year = local_time->tm_year + 1900;
		if (!(flags & 2)) {
			month = local_time->tm_mon + 1;
		}
	} else {
		if (argc == 2) {
			month = xatoul_range(*argv++, 1, 12);
		}
		year = xatoul_range(*argv, 1, 9999);
	}

	blank_string(day_headings, sizeof(day_headings) - 7 +  7*julian);

	i = 0;
	do {
		zero_tm.tm_mon = i;
		strftime(buf, sizeof(buf), "%B", &zero_tm);
		month_names[i] = xstrdup(buf);

		if (i < 7) {
			zero_tm.tm_wday = i;
			strftime(buf, sizeof(buf), "%a", &zero_tm);
			strncpy(day_headings + i * (3+julian) + julian, buf, 2);
		}
	} while (++i < 12);

	if (month) {
		int row, len, days[MAXDAYS];
		int *dp = days;
		char lineout[30];

		day_array(month, year, dp);
		len = sprintf(lineout, "%s %d", month_names[month - 1], year);
		printf("%*s%s\n%s\n",
			   ((7*julian + WEEK_LEN) - len) / 2, "",
			   lineout, day_headings);
		for (row = 0; row < 6; row++) {
			build_row(lineout, dp)[0] = '\0';
			dp += 7;
			trim_trailing_spaces_and_print(lineout);
		}
	} else {
		int row, which_cal, week_len, days[12][MAXDAYS];
		int *dp;
		char lineout[80];

		sprintf(lineout, "%d", year);
		center(lineout,
			   (WEEK_LEN * 3 + HEAD_SEP * 2)
			   + julian * (J_WEEK_LEN * 2 + HEAD_SEP
						   - (WEEK_LEN * 3 + HEAD_SEP * 2)),
			   0);
		puts("\n");		/* two \n's */
		for (i = 0; i < 12; i++) {
			day_array(i + 1, year, days[i]);
		}
		blank_string(lineout, sizeof(lineout));
		week_len = WEEK_LEN + julian * (J_WEEK_LEN - WEEK_LEN);
		for (month = 0; month < 12; month += 3-julian) {
			center(month_names[month], week_len, HEAD_SEP);
			if (!julian) {
				center(month_names[month + 1], week_len, HEAD_SEP);
			}
			center(month_names[month + 2 - julian], week_len, 0);
			printf("\n%s%*s%s", day_headings, HEAD_SEP, "", day_headings);
			if (!julian) {
				printf("%*s%s", HEAD_SEP, "", day_headings);
			}
			putchar('\n');
			for (row = 0; row < (6*7); row += 7) {
				for (which_cal = 0; which_cal < 3-julian; which_cal++) {
					dp = days[month + which_cal] + row;
					build_row(lineout + which_cal * (week_len + 2), dp);
				}
				/* blank_string took care of nul termination. */
				trim_trailing_spaces_and_print(lineout);
			}
		}
	}

	fflush_stdout_and_exit(0);
}

/*
 * day_array --
 *	Fill in an array of 42 integers with a calendar.  Assume for a moment
 *	that you took the (maximum) 6 rows in a calendar and stretched them
 *	out end to end.  You would have 42 numbers or spaces.  This routine
 *	builds that array for any month from Jan. 1 through Dec. 9999.
 */
static void day_array(int month, int year, int *days)
{
	long temp;
	int i;
	int j_offset;
	int day, dw, dm;

	memset(days, SPACE, MAXDAYS * sizeof(int));

	if ((month == 9) && (year == 1752)) {
		size_t oday = 0;

		j_offset = julian * 244;
		do {
			days[oday+2] = sep1752[oday] + j_offset;
		} while (++oday < sizeof(sep1752));

		return;
	}

	/* day_in_year
	 *	return the 1 based day number within the year
	 */
	day = 1;
	if ((month > 2) && leap_year(year)) {
		++day;
	}

	i = month;
	while (i) {
		day += days_in_month[--i];
	}

	/* day_in_week
	 *	return the 0 based day number for any date from 1 Jan. 1 to
	 *	31 Dec. 9999.  Assumes the Gregorian reformation eliminates
	 *	3 Sep. 1752 through 13 Sep. 1752.  Returns Thursday for all
	 *	missing days.
	 */
	dw = THURSDAY;
	temp = (long)(year - 1) * 365 + leap_years_since_year_1(year - 1)
		+ day;
	if (temp < FIRST_MISSING_DAY) {
		dw = ((temp - 1 + SATURDAY) % 7);
	} else if (temp >= (FIRST_MISSING_DAY + NUMBER_MISSING_DAYS)) {
		dw = (((temp - 1 + SATURDAY) - NUMBER_MISSING_DAYS) % 7);
	}

	if (!julian) {
		day = 1;
	}

	dm = days_in_month[month];
	if ((month == 2) && leap_year(year)) {
		++dm;
	}

	while (dm) {
		days[dw++] = day++;
		--dm;
	}
}

static void trim_trailing_spaces_and_print(char *s)
{
	char *p = s;

	while (*p) {
		++p;
	}
	while (p > s) {
		--p;
		if (!(isspace)(*p)) {	/* We want the function... not the inline. */
			p[1] = '\0';
			break;
		}
	}

	puts(s);
}

static void center(char *str, int len, int separate)
{
	int n = strlen(str);
	len -= n;
	printf("%*s%*s", (len/2) + n, str, (len/2) + (len % 2) + separate, "");
}

static void blank_string(char *buf, size_t buflen)
{
	memset(buf, ' ', buflen);
	buf[buflen-1] = '\0';
}

static char *build_row(char *p, int *dp)
{
	int col, val, day;

	memset(p, ' ', (julian + DAY_LEN) * 7);

	col = 0;
	do {
		if ((day = *dp++) != SPACE) {
			if (julian) {
				++p;
				if (day >= 100) {
					*p = '0';
					p[-1] = (day / 100) + '0';
					day %= 100;
				}
			}
			if ((val = day / 10) > 0) {
				*p = val + '0';
			}
			*++p = day % 10 + '0';
			p += 2;
		} else {
			p += DAY_LEN + julian;
		}
	} while (++col < 7);

	return p;
}

/*
 * Copyright (c) 1989, 1993, 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Kim Letkeman.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */


1	niro	532	/* vi: set sw=4 ts=4: */
2			/*
3			* Calendar implementation for busybox
4			*
5			* See original copyright at the end of this file
6			*
7			* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
8			*/
9
10			/* BB_AUDIT SUSv3 compliant with -j and -y extensions (from util-linux). */
11			/* BB_AUDIT BUG: The output of 'cal -j 1752' is incorrect. The upstream
12			* BB_AUDIT BUG: version in util-linux seems to be broken as well. */
13			/* http://www.opengroup.org/onlinepubs/007904975/utilities/cal.html */
14
15			/* Mar 16, 2003 Manuel Novoa III (mjn3@codepoet.org)
16			*
17			* Major size reduction... over 50% (>1.5k) on i386.
18			*/
19
20			#include "busybox.h"
21
22			#define THURSDAY 4 /* for reformation */
23			#define SATURDAY 6 /* 1 Jan 1 was a Saturday */
24
25			#define FIRST_MISSING_DAY 639787 /* 3 Sep 1752 */
26			#define NUMBER_MISSING_DAYS 11 /* 11 day correction */
27
28			#define MAXDAYS 42 /* max slots in a month array */
29			#define SPACE -1 /* used in day array */
30
31			static const char days_in_month[] = {
32			0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
33			};
34
35			static const char sep1752[] = {
36			1, 2, 14, 15, 16,
37			17, 18, 19, 20, 21, 22, 23,
38			24, 25, 26, 27, 28, 29, 30
39			};
40
41			static int julian;
42
43			/* leap year -- account for Gregorian reformation in 1752 */
44			#define leap_year(yr) \
45			((yr) <= 1752 ? !((yr) % 4) : \
46			(!((yr) % 4) && ((yr) % 100)) \|\| !((yr) % 400))
47
48			static int is_leap_year(int year)
49			{
50			return leap_year(year);
51			}
52			#undef leap_year
53			#define leap_year(yr) is_leap_year(yr)
54
55			/* number of centuries since 1700, not inclusive */
56			#define centuries_since_1700(yr) \
57			((yr) > 1700 ? (yr) / 100 - 17 : 0)
58
59			/* number of centuries since 1700 whose modulo of 400 is 0 */
60			#define quad_centuries_since_1700(yr) \
61			((yr) > 1600 ? ((yr) - 1600) / 400 : 0)
62
63			/* number of leap years between year 1 and this year, not inclusive */
64			#define leap_years_since_year_1(yr) \
65			((yr) / 4 - centuries_since_1700(yr) + quad_centuries_since_1700(yr))
66
67			static void center (char *, int, int);
68			static void day_array (int, int, int *);
69			static void trim_trailing_spaces_and_print (char *);
70
71			static void blank_string(char *buf, size_t buflen);
72			static char build_row(char p, int *dp);
73
74			#define DAY_LEN 3 /* 3 spaces per day */
75			#define J_DAY_LEN (DAY_LEN + 1)
76			#define WEEK_LEN 20 /* 7 * 3 - one space at the end */
77			#define J_WEEK_LEN (WEEK_LEN + 7)
78			#define HEAD_SEP 2 /* spaces between day headings */
79
80			int cal_main(int argc, char **argv)
81			{
82			struct tm *local_time;
83			struct tm zero_tm;
84			time_t now;
85			int month, year, flags, i;
86			char *month_names[12];
87			char day_headings[28]; /* 28 for julian, 21 for nonjulian */
88			char buf[40];
89
90			flags = getopt32(argc, argv, "jy");
91
92			julian = flags & 1;
93
94			argv += optind;
95
96			month = 0;
97
98			if ((argc -= optind) > 2) {
99			bb_show_usage();
100			}
101
102			if (!argc) {
103			time(&now);
104			local_time = localtime(&now);
105			year = local_time->tm_year + 1900;
106			if (!(flags & 2)) {
107			month = local_time->tm_mon + 1;
108			}
109			} else {
110			if (argc == 2) {
111			month = xatoul_range(*argv++, 1, 12);
112			}
113			year = xatoul_range(*argv, 1, 9999);
114			}
115
116			blank_string(day_headings, sizeof(day_headings) - 7 + 7*julian);
117
118			i = 0;
119			do {
120			zero_tm.tm_mon = i;
121			strftime(buf, sizeof(buf), "%B", &zero_tm);
122			month_names[i] = xstrdup(buf);
123
124			if (i < 7) {
125			zero_tm.tm_wday = i;
126			strftime(buf, sizeof(buf), "%a", &zero_tm);
127			strncpy(day_headings + i * (3+julian) + julian, buf, 2);
128			}
129			} while (++i < 12);
130
131			if (month) {
132			int row, len, days[MAXDAYS];
133			int *dp = days;
134			char lineout[30];
135
136			day_array(month, year, dp);
137			len = sprintf(lineout, "%s %d", month_names[month - 1], year);
138			printf("%*s%s\n%s\n",
139			((7*julian + WEEK_LEN) - len) / 2, "",
140			lineout, day_headings);
141			for (row = 0; row < 6; row++) {
142			build_row(lineout, dp)[0] = '\0';
143			dp += 7;
144			trim_trailing_spaces_and_print(lineout);
145			}
146			} else {
147			int row, which_cal, week_len, days[12][MAXDAYS];
148			int *dp;
149			char lineout[80];
150
151			sprintf(lineout, "%d", year);
152			center(lineout,
153			(WEEK_LEN * 3 + HEAD_SEP * 2)
154			+ julian * (J_WEEK_LEN * 2 + HEAD_SEP
155			- (WEEK_LEN * 3 + HEAD_SEP * 2)),
156			0);
157			puts("\n"); /* two \n's */
158			for (i = 0; i < 12; i++) {
159			day_array(i + 1, year, days[i]);
160			}
161			blank_string(lineout, sizeof(lineout));
162			week_len = WEEK_LEN + julian * (J_WEEK_LEN - WEEK_LEN);
163			for (month = 0; month < 12; month += 3-julian) {
164			center(month_names[month], week_len, HEAD_SEP);
165			if (!julian) {
166			center(month_names[month + 1], week_len, HEAD_SEP);
167			}
168			center(month_names[month + 2 - julian], week_len, 0);
169			printf("\n%s%*s%s", day_headings, HEAD_SEP, "", day_headings);
170			if (!julian) {
171			printf("%*s%s", HEAD_SEP, "", day_headings);
172			}
173			putchar('\n');
174			for (row = 0; row < (6*7); row += 7) {
175			for (which_cal = 0; which_cal < 3-julian; which_cal++) {
176			dp = days[month + which_cal] + row;
177			build_row(lineout + which_cal * (week_len + 2), dp);
178			}
179			/* blank_string took care of nul termination. */
180			trim_trailing_spaces_and_print(lineout);
181			}
182			}
183			}
184
185			fflush_stdout_and_exit(0);
186			}
187
188			/*
189			* day_array --
190			* Fill in an array of 42 integers with a calendar. Assume for a moment
191			* that you took the (maximum) 6 rows in a calendar and stretched them
192			* out end to end. You would have 42 numbers or spaces. This routine
193			* builds that array for any month from Jan. 1 through Dec. 9999.
194			*/
195			static void day_array(int month, int year, int *days)
196			{
197			long temp;
198			int i;
199			int j_offset;
200			int day, dw, dm;
201
202			memset(days, SPACE, MAXDAYS * sizeof(int));
203
204			if ((month == 9) && (year == 1752)) {
205			size_t oday = 0;
206
207			j_offset = julian * 244;
208			do {
209			days[oday+2] = sep1752[oday] + j_offset;
210			} while (++oday < sizeof(sep1752));
211
212			return;
213			}
214
215			/* day_in_year
216			* return the 1 based day number within the year
217			*/
218			day = 1;
219			if ((month > 2) && leap_year(year)) {
220			++day;
221			}
222
223			i = month;
224			while (i) {
225			day += days_in_month[--i];
226			}
227
228			/* day_in_week
229			* return the 0 based day number for any date from 1 Jan. 1 to
230			* 31 Dec. 9999. Assumes the Gregorian reformation eliminates
231			* 3 Sep. 1752 through 13 Sep. 1752. Returns Thursday for all
232			* missing days.
233			*/
234			dw = THURSDAY;
235			temp = (long)(year - 1) * 365 + leap_years_since_year_1(year - 1)
236			+ day;
237			if (temp < FIRST_MISSING_DAY) {
238			dw = ((temp - 1 + SATURDAY) % 7);
239			} else if (temp >= (FIRST_MISSING_DAY + NUMBER_MISSING_DAYS)) {
240			dw = (((temp - 1 + SATURDAY) - NUMBER_MISSING_DAYS) % 7);
241			}
242
243			if (!julian) {
244			day = 1;
245			}
246
247			dm = days_in_month[month];
248			if ((month == 2) && leap_year(year)) {
249			++dm;
250			}
251
252			while (dm) {
253			days[dw++] = day++;
254			--dm;
255			}
256			}
257
258			static void trim_trailing_spaces_and_print(char *s)
259			{
260			char *p = s;
261
262			while (*p) {
263			++p;
264			}
265			while (p > s) {
266			--p;
267			if (!(isspace)(p)) { / We want the function... not the inline. */
268			p[1] = '\0';
269			break;
270			}
271			}
272
273			puts(s);
274			}
275
276			static void center(char *str, int len, int separate)
277			{
278			int n = strlen(str);
279			len -= n;
280			printf("%s%s", (len/2) + n, str, (len/2) + (len % 2) + separate, "");
281			}
282
283			static void blank_string(char *buf, size_t buflen)
284			{
285			memset(buf, ' ', buflen);
286			buf[buflen-1] = '\0';
287			}
288
289			static char build_row(char p, int *dp)
290			{
291			int col, val, day;
292
293			memset(p, ' ', (julian + DAY_LEN) * 7);
294
295			col = 0;
296			do {
297			if ((day = *dp++) != SPACE) {
298			if (julian) {
299			++p;
300			if (day >= 100) {
301			*p = '0';
302			p[-1] = (day / 100) + '0';
303			day %= 100;
304			}
305			}
306			if ((val = day / 10) > 0) {
307			*p = val + '0';
308			}
309			*++p = day % 10 + '0';
310			p += 2;
311			} else {
312			p += DAY_LEN + julian;
313			}
314			} while (++col < 7);
315
316			return p;
317			}
318
319			/*
320			* Copyright (c) 1989, 1993, 1994
321			* The Regents of the University of California. All rights reserved.
322			*
323			* This code is derived from software contributed to Berkeley by
324			* Kim Letkeman.
325			*
326			* Redistribution and use in source and binary forms, with or without
327			* modification, are permitted provided that the following conditions
328			* are met:
329			* 1. Redistributions of source code must retain the above copyright
330			* notice, this list of conditions and the following disclaimer.
331			* 2. Redistributions in binary form must reproduce the above copyright
332			* notice, this list of conditions and the following disclaimer in the
333			* documentation and/or other materials provided with the distribution.
334			* 3. Neither the name of the University nor the names of its contributors
335			* may be used to endorse or promote products derived from this software
336			* without specific prior written permission.
337			*
338			* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
339			* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
340			* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
341			* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
342			* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
343			* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
344			* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
345			* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
346			* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
347			* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
348			* SUCH DAMAGE.
349			*/
350
351