summaryrefslogtreecommitdiff
path: root/coreutils/cal.c (plain)
blob: 4f5bbf7c98a6011acd3db68fa276ddd6bd79e3ea
1/* 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 source tree.
8 */
9/* Mar 16, 2003 Manuel Novoa III (mjn3@codepoet.org)
10 *
11 * Major size reduction... over 50% (>1.5k) on i386.
12 */
13//config:config CAL
14//config: bool "cal"
15//config: default y
16//config: help
17//config: cal is used to display a monthly calendar.
18
19//applet:IF_CAL(APPLET(cal, BB_DIR_USR_BIN, BB_SUID_DROP))
20
21//kbuild:lib-$(CONFIG_CAL) += cal.o
22
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 */
27
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"
34
35#include "libbb.h"
36#include "unicode.h"
37
38/* We often use "unsigned" intead of "int", it's easier to div on most CPUs */
39
40#define THURSDAY 4 /* for reformation */
41#define SATURDAY 6 /* 1 Jan 1 was a Saturday */
42
43#define FIRST_MISSING_DAY 639787 /* 3 Sep 1752 */
44#define NUMBER_MISSING_DAYS 11 /* 11 day correction */
45
46#define MAXDAYS 42 /* max slots in a month array */
47#define SPACE -1 /* used in day array */
48
49static const unsigned char days_in_month[] ALIGN1 = {
50 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
51};
52
53static const unsigned char sep1752[] ALIGN1 = {
54 1, 2, 14, 15, 16,
55 17, 18, 19, 20, 21, 22, 23,
56 24, 25, 26, 27, 28, 29, 30
57};
58
59/* Set to 0 or 1 in main */
60#define julian ((unsigned)option_mask32)
61
62/* leap year -- account for Gregorian reformation in 1752 */
63static int leap_year(unsigned yr)
64{
65 if (yr <= 1752)
66 return !(yr % 4);
67 return (!(yr % 4) && (yr % 100)) || !(yr % 400);
68}
69
70/* number of centuries since 1700, not inclusive */
71#define centuries_since_1700(yr) \
72 ((yr) > 1700 ? (yr) / 100 - 17 : 0)
73
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)
77
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))
81
82static void center(char *, unsigned, unsigned);
83static void day_array(unsigned, unsigned, unsigned *);
84static void trim_trailing_spaces_and_print(char *);
85
86static void blank_string(char *buf, size_t buflen);
87static char *build_row(char *p, unsigned *dp);
88
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 */
94
95int cal_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
96int cal_main(int argc UNUSED_PARAM, char **argv)
97{
98 struct tm zero_tm;
99 time_t now;
100 unsigned month, year, flags, i;
101 char *month_names[12];
102 /* normal heading: */
103 /* "Su Mo Tu We Th Fr Sa" */
104 /* -j heading: */
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;)
108 char buf[40];
109
110 init_unicode();
111
112 flags = getopt32(argv, "jy");
113 /* This sets julian = flags & 1: */
114 option_mask32 &= 1;
115 month = 0;
116 argv += optind;
117
118 if (!argv[0]) {
119 struct tm *ptm;
120
121 time(&now);
122 ptm = localtime(&now);
123 year = ptm->tm_year + 1900;
124 if (!(flags & 2)) { /* no -y */
125 month = ptm->tm_mon + 1;
126 }
127 } else {
128 if (argv[1]) {
129 if (argv[2]) {
130 bb_show_usage();
131 }
132 if (!(flags & 2)) { /* no -y */
133 month = xatou_range(*argv, 1, 12);
134 }
135 argv++;
136 }
137 year = xatou_range(*argv, 1, 9999);
138 }
139
140 blank_string(day_headings, sizeof(day_headings) - 7 + 7*julian);
141
142 i = 0;
143 do {
144 zero_tm.tm_mon = i;
145 /* full month name according to locale */
146 strftime(buf, sizeof(buf), "%B", &zero_tm);
147 month_names[i] = xstrdup(buf);
148
149 if (i < 7) {
150 zero_tm.tm_wday = i;
151 /* abbreviated weekday name according to locale */
152 strftime(buf, sizeof(buf), "%a", &zero_tm);
153#if ENABLE_UNICODE_SUPPORT
154 if (julian)
155 *hp++ = ' ';
156 {
157 char *two_wchars = unicode_conv_to_printable_fixedwidth(/*NULL,*/ buf, 2);
158 strcpy(hp, two_wchars);
159 free(two_wchars);
160 }
161 hp += strlen(hp);
162 *hp++ = ' ';
163#else
164 strncpy(day_headings + i * (3+julian) + julian, buf, 2);
165#endif
166 }
167 } while (++i < 12);
168 IF_UNICODE_SUPPORT(hp[-1] = '\0';)
169
170 if (month) {
171 unsigned row, len, days[MAXDAYS];
172 unsigned *dp = days;
173 char lineout[30];
174
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';
182 dp += 7;
183 trim_trailing_spaces_and_print(lineout);
184 }
185 } else {
186 unsigned row, which_cal, week_len, days[12][MAXDAYS];
187 unsigned *dp;
188 char lineout[80];
189
190 sprintf(lineout, "%u", year);
191 center(lineout,
192 (WEEK_LEN * 3 + HEAD_SEP * 2)
193 + julian * (J_WEEK_LEN * 2 + HEAD_SEP
194 - (WEEK_LEN * 3 + HEAD_SEP * 2)),
195 0
196 );
197 puts("\n"); /* two \n's */
198 for (i = 0; i < 12; i++) {
199 day_array(i + 1, year, days[i]);
200 }
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);
205 if (!julian) {
206 center(month_names[month + 1], week_len, HEAD_SEP);
207 }
208 center(month_names[month + 2 - julian], week_len, 0);
209 printf("\n%s%*s%s", day_headings, HEAD_SEP, "", day_headings);
210 if (!julian) {
211 printf("%*s%s", HEAD_SEP, "", day_headings);
212 }
213 bb_putchar('\n');
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);
218 }
219 /* blank_string took care of nul termination. */
220 trim_trailing_spaces_and_print(lineout);
221 }
222 }
223 }
224
225 fflush_stdout_and_exit(EXIT_SUCCESS);
226}
227
228/*
229 * day_array --
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.
234 */
235static void day_array(unsigned month, unsigned year, unsigned *days)
236{
237 unsigned long temp;
238 unsigned i;
239 unsigned day, dw, dm;
240
241 memset(days, SPACE, MAXDAYS * sizeof(int));
242
243 if ((month == 9) && (year == 1752)) {
244 /* Assumes the Gregorian reformation eliminates
245 * 3 Sep. 1752 through 13 Sep. 1752.
246 */
247 unsigned j_offset = julian * 244;
248 size_t oday = 0;
249
250 do {
251 days[oday+2] = sep1752[oday] + j_offset;
252 } while (++oday < sizeof(sep1752));
253
254 return;
255 }
256
257 /* day_in_year
258 * return the 1 based day number within the year
259 */
260 day = 1;
261 if ((month > 2) && leap_year(year)) {
262 ++day;
263 }
264
265 i = month;
266 while (i) {
267 day += days_in_month[--i];
268 }
269
270 /* day_in_week
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
274 * missing days.
275 */
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);
279 } else {
280 dw = (((temp - 1 + SATURDAY) - NUMBER_MISSING_DAYS) % 7);
281 }
282
283 if (!julian) {
284 day = 1;
285 }
286
287 dm = days_in_month[month];
288 if ((month == 2) && leap_year(year)) {
289 ++dm;
290 }
291
292 do {
293 days[dw++] = day++;
294 } while (--dm);
295}
296
297static void trim_trailing_spaces_and_print(char *s)
298{
299 char *p = s;
300
301 while (*p) {
302 ++p;
303 }
304 while (p != s) {
305 --p;
306 if (!isspace(*p)) {
307 p[1] = '\0';
308 break;
309 }
310 }
311
312 puts(s);
313}
314
315static void center(char *str, unsigned len, unsigned separate)
316{
317 unsigned n = strlen(str);
318 len -= n;
319 printf("%*s%*s", (len/2) + n, str, (len/2) + (len % 2) + separate, "");
320}
321
322static void blank_string(char *buf, size_t buflen)
323{
324 memset(buf, ' ', buflen);
325 buf[buflen-1] = '\0';
326}
327
328static char *build_row(char *p, unsigned *dp)
329{
330 unsigned col, val, day;
331
332 memset(p, ' ', (julian + DAY_LEN) * 7);
333
334 col = 0;
335 do {
336 day = *dp++;
337 if (day != (unsigned) SPACE) {
338 if (julian) {
339 ++p;
340 if (day >= 100) {
341 *p = '0';
342 p[-1] = (day / 100) + '0';
343 day %= 100;
344 }
345 }
346 val = day / 10;
347 if (val > 0) {
348 *p = val + '0';
349 }
350 *++p = day % 10 + '0';
351 p += 2;
352 } else {
353 p += DAY_LEN + julian;
354 }
355 } while (++col < 7);
356
357 return p;
358}
359
360/*
361 * Copyright (c) 1989, 1993, 1994
362 * The Regents of the University of California. All rights reserved.
363 *
364 * This code is derived from software contributed to Berkeley by
365 * Kim Letkeman.
366 *
367 * Redistribution and use in source and binary forms, with or without
368 * modification, are permitted provided that the following conditions
369 * are met:
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.
378 *
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
389 * SUCH DAMAGE.
390 */
391
generated by cgit at 2024-05-15 12:15:11 (GMT)