1 /* vi: set sw=4 ts=4: */
3 * Calendar implementation for busybox
5 * See original copyright at the end of this file
7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
9 /* Mar 16, 2003 Manuel Novoa III (mjn3@codepoet.org)
11 * Major size reduction... over 50% (>1.5k) on i386.
17 //config: cal is used to display a monthly calendar.
19 //applet:IF_CAL(APPLET(cal, BB_DIR_USR_BIN, BB_SUID_DROP))
21 //kbuild:lib-$(CONFIG_CAL) += cal.o
23 /* BB_AUDIT SUSv3 compliant with -j and -y extensions (from util-linux). */
24 /* BB_AUDIT BUG: The output of 'cal -j 1752' is incorrect. The upstream
25 * BB_AUDIT BUG: version in util-linux seems to be broken as well. */
26 /* http://www.opengroup.org/onlinepubs/007904975/utilities/cal.html */
28 //usage:#define cal_trivial_usage
29 //usage: "[-jy] [[MONTH] YEAR]"
30 //usage:#define cal_full_usage "\n\n"
31 //usage: "Display a calendar\n"
32 //usage: "\n -j Use julian dates"
33 //usage: "\n -y Display the entire year"
38 /* We often use "unsigned" instead of "int", it's easier to div on most CPUs */
40 #define THURSDAY 4 /* for reformation */
41 #define SATURDAY 6 /* 1 Jan 1 was a Saturday */
43 #define FIRST_MISSING_DAY 639787 /* 3 Sep 1752 */
44 #define NUMBER_MISSING_DAYS 11 /* 11 day correction */
46 #define MAXDAYS 42 /* max slots in a month array */
47 #define SPACE -1 /* used in day array */
49 static const unsigned char days_in_month[] ALIGN1 = {
50 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
53 static const unsigned char sep1752[] ALIGN1 = {
55 17, 18, 19, 20, 21, 22, 23,
56 24, 25, 26, 27, 28, 29, 30
59 /* Set to 0 or 1 in main */
60 #define julian ((unsigned)option_mask32)
62 /* leap year -- account for Gregorian reformation in 1752 */
63 static int leap_year(unsigned yr)
67 return (!(yr % 4) && (yr % 100)) || !(yr % 400);
70 /* number of centuries since 1700, not inclusive */
71 #define centuries_since_1700(yr) \
72 ((yr) > 1700 ? (yr) / 100 - 17 : 0)
74 /* number of centuries since 1700 whose modulo of 400 is 0 */
75 #define quad_centuries_since_1700(yr) \
76 ((yr) > 1600 ? ((yr) - 1600) / 400 : 0)
78 /* number of leap years between year 1 and this year, not inclusive */
79 #define leap_years_since_year_1(yr) \
80 ((yr) / 4 - centuries_since_1700(yr) + quad_centuries_since_1700(yr))
82 static void center(char *, unsigned, unsigned);
83 static void day_array(unsigned, unsigned, unsigned *);
84 static void trim_trailing_spaces_and_print(char *);
86 static void blank_string(char *buf, size_t buflen);
87 static char *build_row(char *p, unsigned *dp);
89 #define DAY_LEN 3 /* 3 spaces per day */
90 #define J_DAY_LEN (DAY_LEN + 1)
91 #define WEEK_LEN 20 /* 7 * 3 - one space at the end */
92 #define J_WEEK_LEN (WEEK_LEN + 7)
93 #define HEAD_SEP 2 /* spaces between day headings */
95 int cal_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
96 int cal_main(int argc UNUSED_PARAM, char **argv)
100 unsigned month, year, flags, i;
101 char *month_names[12];
102 /* normal heading: */
103 /* "Su Mo Tu We Th Fr Sa" */
105 /* " Su Mo Tu We Th Fr Sa" */
106 char day_headings[ENABLE_UNICODE_SUPPORT ? 28 * 6 : 28];
107 IF_UNICODE_SUPPORT(char *hp = day_headings;)
112 flags = getopt32(argv, "jy");
113 /* This sets julian = flags & 1: */
122 ptm = localtime(&now);
123 year = ptm->tm_year + 1900;
124 if (!(flags & 2)) { /* no -y */
125 month = ptm->tm_mon + 1;
132 if (!(flags & 2)) { /* no -y */
133 month = xatou_range(*argv, 1, 12);
137 year = xatou_range(*argv, 1, 9999);
140 blank_string(day_headings, sizeof(day_headings) - 7 + 7*julian);
145 /* full month name according to locale */
146 strftime(buf, sizeof(buf), "%B", &zero_tm);
147 month_names[i] = xstrdup(buf);
151 /* abbreviated weekday name according to locale */
152 strftime(buf, sizeof(buf), "%a", &zero_tm);
153 #if ENABLE_UNICODE_SUPPORT
157 char *two_wchars = unicode_conv_to_printable_fixedwidth(/*NULL,*/ buf, 2);
158 strcpy(hp, two_wchars);
164 strncpy(day_headings + i * (3+julian) + julian, buf, 2);
168 IF_UNICODE_SUPPORT(hp[-1] = '\0';)
171 unsigned row, len, days[MAXDAYS];
175 day_array(month, year, dp);
176 len = sprintf(lineout, "%s %u", month_names[month - 1], year);
177 printf("%*s%s\n%s\n",
178 ((7*julian + WEEK_LEN) - len) / 2, "",
179 lineout, day_headings);
180 for (row = 0; row < 6; row++) {
181 build_row(lineout, dp)[0] = '\0';
183 trim_trailing_spaces_and_print(lineout);
186 unsigned row, which_cal, week_len, days[12][MAXDAYS];
190 sprintf(lineout, "%u", year);
192 (WEEK_LEN * 3 + HEAD_SEP * 2)
193 + julian * (J_WEEK_LEN * 2 + HEAD_SEP
194 - (WEEK_LEN * 3 + HEAD_SEP * 2)),
197 puts("\n"); /* two \n's */
198 for (i = 0; i < 12; i++) {
199 day_array(i + 1, year, days[i]);
201 blank_string(lineout, sizeof(lineout));
202 week_len = WEEK_LEN + julian * (J_WEEK_LEN - WEEK_LEN);
203 for (month = 0; month < 12; month += 3-julian) {
204 center(month_names[month], week_len, HEAD_SEP);
206 center(month_names[month + 1], week_len, HEAD_SEP);
208 center(month_names[month + 2 - julian], week_len, 0);
209 printf("\n%s%*s%s", day_headings, HEAD_SEP, "", day_headings);
211 printf("%*s%s", HEAD_SEP, "", day_headings);
214 for (row = 0; row < (6*7); row += 7) {
215 for (which_cal = 0; which_cal < 3-julian; which_cal++) {
216 dp = days[month + which_cal] + row;
217 build_row(lineout + which_cal * (week_len + 2), dp);
219 /* blank_string took care of nul termination. */
220 trim_trailing_spaces_and_print(lineout);
225 fflush_stdout_and_exit(EXIT_SUCCESS);
230 * Fill in an array of 42 integers with a calendar. Assume for a moment
231 * that you took the (maximum) 6 rows in a calendar and stretched them
232 * out end to end. You would have 42 numbers or spaces. This routine
233 * builds that array for any month from Jan. 1 through Dec. 9999.
235 static void day_array(unsigned month, unsigned year, unsigned *days)
239 unsigned day, dw, dm;
241 memset(days, SPACE, MAXDAYS * sizeof(int));
243 if ((month == 9) && (year == 1752)) {
244 /* Assumes the Gregorian reformation eliminates
245 * 3 Sep. 1752 through 13 Sep. 1752.
247 unsigned j_offset = julian * 244;
251 days[oday+2] = sep1752[oday] + j_offset;
252 } while (++oday < sizeof(sep1752));
258 * return the 1 based day number within the year
261 if ((month > 2) && leap_year(year)) {
267 day += days_in_month[--i];
271 * return the 0 based day number for any date from 1 Jan. 1 to
272 * 31 Dec. 9999. Assumes the Gregorian reformation eliminates
273 * 3 Sep. 1752 through 13 Sep. 1752. Returns Thursday for all
276 temp = (long)(year - 1) * 365 + leap_years_since_year_1(year - 1) + day;
277 if (temp < FIRST_MISSING_DAY) {
278 dw = ((temp - 1 + SATURDAY) % 7);
280 dw = (((temp - 1 + SATURDAY) - NUMBER_MISSING_DAYS) % 7);
287 dm = days_in_month[month];
288 if ((month == 2) && leap_year(year)) {
297 static void trim_trailing_spaces_and_print(char *s)
315 static void center(char *str, unsigned len, unsigned separate)
317 unsigned n = strlen(str);
319 printf("%*s%*s", (len/2) + n, str, (len/2) + (len % 2) + separate, "");
322 static void blank_string(char *buf, size_t buflen)
324 memset(buf, ' ', buflen);
325 buf[buflen-1] = '\0';
328 static char *build_row(char *p, unsigned *dp)
330 unsigned col, val, day;
332 memset(p, ' ', (julian + DAY_LEN) * 7);
342 p[-1] = (day / 100) + '0';
350 *++p = day % 10 + '0';
353 p += DAY_LEN + julian;
361 * Copyright (c) 1989, 1993, 1994
362 * The Regents of the University of California. All rights reserved.
364 * This code is derived from software contributed to Berkeley by
367 * Redistribution and use in source and binary forms, with or without
368 * modification, are permitted provided that the following conditions
370 * 1. Redistributions of source code must retain the above copyright
371 * notice, this list of conditions and the following disclaimer.
372 * 2. Redistributions in binary form must reproduce the above copyright
373 * notice, this list of conditions and the following disclaimer in the
374 * documentation and/or other materials provided with the distribution.
375 * 3. Neither the name of the University nor the names of its contributors
376 * may be used to endorse or promote products derived from this software
377 * without specific prior written permission.
379 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
380 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
381 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
382 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
383 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
384 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
385 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
386 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
387 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
388 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF