cal.c 11 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403
  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 (5.8 kb)"
  15. //config: default y
  16. //config: help
  17. //config: cal is used to display a monthly calendar.
  18. //applet:IF_CAL(APPLET_NOEXEC(cal, cal, BB_DIR_USR_BIN, BB_SUID_DROP, cal))
  19. /* NOEXEC despite rare cases when it can be a "runner" (e.g. cal -n12000 takes you into years 30xx) */
  20. //kbuild:lib-$(CONFIG_CAL) += cal.o
  21. /* BB_AUDIT SUSv3 compliant with -j and -y extensions (from util-linux). */
  22. /* BB_AUDIT BUG: The output of 'cal -j 1752' is incorrect. The upstream
  23. * BB_AUDIT BUG: version in util-linux seems to be broken as well. */
  24. /* http://www.opengroup.org/onlinepubs/007904975/utilities/cal.html */
  25. //usage:#define cal_trivial_usage
  26. //usage: "[-jmy] [[MONTH] YEAR]"
  27. //usage:#define cal_full_usage "\n\n"
  28. //usage: "Display a calendar\n"
  29. //usage: "\n -j Use julian dates"
  30. //usage: "\n -m Week starts on Monday"
  31. //usage: "\n -y Display the entire year"
  32. #include "libbb.h"
  33. #include "unicode.h"
  34. /* We often use "unsigned" instead of "int", it's easier to div on most CPUs */
  35. #define SUNDAY 0
  36. #define MONDAY 1
  37. #define THURSDAY 4 /* for reformation */
  38. #define SATURDAY 6 /* 1 Jan 1 was a Saturday */
  39. #define FIRST_MISSING_DAY 639787 /* 3 Sep 1752 */
  40. #define NUMBER_MISSING_DAYS 11 /* 11 day correction */
  41. #define MAXDAYS 42 /* max slots in a month array */
  42. #define SPACE -1 /* used in day array */
  43. static const unsigned char days_in_month[] ALIGN1 = {
  44. 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
  45. };
  46. static const unsigned char sep1752[] ALIGN1 = {
  47. 1, 2, 14, 15, 16,
  48. 17, 18, 19, 20, 21, 22, 23,
  49. 24, 25, 26, 27, 28, 29, 30
  50. };
  51. /* Set to 0 or 1 in main */
  52. #define julian ((unsigned)option_mask32)
  53. /* leap year -- account for Gregorian reformation in 1752 */
  54. static int leap_year(unsigned yr)
  55. {
  56. if (yr <= 1752)
  57. return !(yr % 4);
  58. return (!(yr % 4) && (yr % 100)) || !(yr % 400);
  59. }
  60. /* number of centuries since 1700, not inclusive */
  61. #define centuries_since_1700(yr) \
  62. ((yr) > 1700 ? (yr) / 100 - 17 : 0)
  63. /* number of centuries since 1700 whose modulo of 400 is 0 */
  64. #define quad_centuries_since_1700(yr) \
  65. ((yr) > 1600 ? ((yr) - 1600) / 400 : 0)
  66. /* number of leap years between year 1 and this year, not inclusive */
  67. #define leap_years_since_year_1(yr) \
  68. ((yr) / 4 - centuries_since_1700(yr) + quad_centuries_since_1700(yr))
  69. static void center(char *, unsigned, unsigned);
  70. static void day_array(unsigned, unsigned, unsigned, unsigned *);
  71. static void trim_trailing_spaces_and_print(char *);
  72. static void blank_string(char *buf, size_t buflen);
  73. static char *build_row(char *p, unsigned *dp);
  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. enum {
  80. OPT_JULIAN = (1 << 0),
  81. OPT_MONDAY = (1 << 1),
  82. OPT_YEAR = (1 << 2),
  83. };
  84. int cal_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  85. int cal_main(int argc UNUSED_PARAM, char **argv)
  86. {
  87. struct tm zero_tm;
  88. time_t now;
  89. unsigned month, year, flags, i, weekstart;
  90. char *month_names[12];
  91. /* normal heading: */
  92. /* "Su Mo Tu We Th Fr Sa" */
  93. /* -j heading: */
  94. /* " Su Mo Tu We Th Fr Sa" */
  95. char day_headings[ENABLE_UNICODE_SUPPORT ? 28 * 6 : 28];
  96. IF_UNICODE_SUPPORT(char *hp = day_headings;)
  97. char buf[40];
  98. init_unicode();
  99. flags = getopt32(argv, "jmy");
  100. /* This sets julian = flags & OPT_JULIAN: */
  101. option_mask32 &= OPT_JULIAN;
  102. month = 0;
  103. weekstart = (flags & OPT_MONDAY) ? MONDAY : SUNDAY;
  104. argv += optind;
  105. if (!argv[0]) {
  106. struct tm *ptm;
  107. time(&now);
  108. ptm = localtime(&now);
  109. year = ptm->tm_year + 1900;
  110. if (!(flags & OPT_YEAR)) { /* no -y */
  111. month = ptm->tm_mon + 1;
  112. }
  113. } else {
  114. if (argv[1]) {
  115. if (argv[2]) {
  116. bb_show_usage();
  117. }
  118. if (!(flags & OPT_YEAR)) { /* no -y */
  119. month = xatou_range(*argv, 1, 12);
  120. }
  121. argv++;
  122. }
  123. year = xatou_range(*argv, 1, 9999);
  124. }
  125. blank_string(day_headings, sizeof(day_headings) - 7 + 7*julian);
  126. i = 0;
  127. do {
  128. zero_tm.tm_mon = i;
  129. /* full month name according to locale */
  130. strftime(buf, sizeof(buf), "%B", &zero_tm);
  131. month_names[i] = xstrdup(buf);
  132. if (i < 7) {
  133. zero_tm.tm_wday = (i + weekstart) % 7;
  134. /* abbreviated weekday name according to locale */
  135. strftime(buf, sizeof(buf), "%a", &zero_tm);
  136. #if ENABLE_UNICODE_SUPPORT
  137. if (julian)
  138. *hp++ = ' ';
  139. {
  140. char *two_wchars = unicode_conv_to_printable_fixedwidth(/*NULL,*/ buf, 2);
  141. strcpy(hp, two_wchars);
  142. free(two_wchars);
  143. }
  144. hp += strlen(hp);
  145. *hp++ = ' ';
  146. #else
  147. strncpy(day_headings + i * (3+julian) + julian, buf, 2);
  148. #endif
  149. }
  150. } while (++i < 12);
  151. IF_UNICODE_SUPPORT(hp[-1] = '\0';)
  152. if (month) {
  153. unsigned row, len, days[MAXDAYS];
  154. unsigned *dp = days;
  155. char lineout[30];
  156. day_array(month, year, weekstart, dp);
  157. len = sprintf(lineout, "%s %u", month_names[month - 1], year);
  158. printf("%*s%s\n%s\n",
  159. ((7*julian + WEEK_LEN) - len) / 2, "",
  160. lineout, day_headings);
  161. for (row = 0; row < 6; row++) {
  162. build_row(lineout, dp)[0] = '\0';
  163. dp += 7;
  164. trim_trailing_spaces_and_print(lineout);
  165. }
  166. } else {
  167. unsigned row, which_cal, week_len, days[12][MAXDAYS];
  168. unsigned *dp;
  169. char lineout[80];
  170. sprintf(lineout, "%u", year);
  171. center(lineout,
  172. (WEEK_LEN * 3 + HEAD_SEP * 2)
  173. + julian * (J_WEEK_LEN * 2 + HEAD_SEP
  174. - (WEEK_LEN * 3 + HEAD_SEP * 2)),
  175. 0
  176. );
  177. puts("\n"); /* two \n's */
  178. for (i = 0; i < 12; i++) {
  179. day_array(i + 1, year, weekstart, days[i]);
  180. }
  181. blank_string(lineout, sizeof(lineout));
  182. week_len = WEEK_LEN + julian * (J_WEEK_LEN - WEEK_LEN);
  183. for (month = 0; month < 12; month += 3-julian) {
  184. center(month_names[month], week_len, HEAD_SEP);
  185. if (!julian) {
  186. center(month_names[month + 1], week_len, HEAD_SEP);
  187. }
  188. center(month_names[month + 2 - julian], week_len, 0);
  189. printf("\n%s%*s%s", day_headings, HEAD_SEP, "", day_headings);
  190. if (!julian) {
  191. printf("%*s%s", HEAD_SEP, "", day_headings);
  192. }
  193. bb_putchar('\n');
  194. for (row = 0; row < (6*7); row += 7) {
  195. for (which_cal = 0; which_cal < 3-julian; which_cal++) {
  196. dp = days[month + which_cal] + row;
  197. build_row(lineout + which_cal * (week_len + 2), dp);
  198. }
  199. /* blank_string took care of nul termination. */
  200. trim_trailing_spaces_and_print(lineout);
  201. }
  202. }
  203. }
  204. fflush_stdout_and_exit_SUCCESS();
  205. }
  206. /*
  207. * day_array --
  208. * Fill in an array of 42 integers with a calendar. Assume for a moment
  209. * that you took the (maximum) 6 rows in a calendar and stretched them
  210. * out end to end. You would have 42 numbers or spaces. This routine
  211. * builds that array for any month from Jan. 1 through Dec. 9999.
  212. */
  213. static void day_array(unsigned month, unsigned year, unsigned weekstart,
  214. unsigned *days)
  215. {
  216. unsigned long temp;
  217. unsigned i;
  218. unsigned day, dw, dm;
  219. memset(days, SPACE, MAXDAYS * sizeof(int));
  220. if ((month == 9) && (year == 1752)) {
  221. /* Assumes the Gregorian reformation eliminates
  222. * 3 Sep. 1752 through 13 Sep. 1752.
  223. */
  224. unsigned j_offset = julian * 244;
  225. size_t oday = 0;
  226. do {
  227. days[oday+2-weekstart] = sep1752[oday] + j_offset;
  228. } while (++oday < sizeof(sep1752));
  229. return;
  230. }
  231. /* day_in_year
  232. * return the 1 based day number within the year
  233. */
  234. day = 1;
  235. if ((month > 2) && leap_year(year)) {
  236. ++day;
  237. }
  238. i = month;
  239. while (i) {
  240. day += days_in_month[--i];
  241. }
  242. /* day_in_week
  243. * return the 0 based day number for any date from 1 Jan. 1 to
  244. * 31 Dec. 9999. Assumes the Gregorian reformation eliminates
  245. * 3 Sep. 1752 through 13 Sep. 1752. Returns Thursday for all
  246. * missing days.
  247. */
  248. temp = (long)(year - 1) * 365 + leap_years_since_year_1(year - 1) + day;
  249. if (temp < FIRST_MISSING_DAY) {
  250. dw = ((temp - 1 + SATURDAY) % 7);
  251. } else {
  252. dw = (((temp - 1 + SATURDAY) - NUMBER_MISSING_DAYS) % 7);
  253. }
  254. dw = (dw - weekstart + 7) % 7;
  255. if (!julian) {
  256. day = 1;
  257. }
  258. dm = days_in_month[month];
  259. if ((month == 2) && leap_year(year)) {
  260. ++dm;
  261. }
  262. do {
  263. days[dw++] = day++;
  264. } while (--dm);
  265. }
  266. static void trim_trailing_spaces_and_print(char *s)
  267. {
  268. char *p = s;
  269. while (*p) {
  270. ++p;
  271. }
  272. while (p != s) {
  273. --p;
  274. if (!isspace(*p)) {
  275. p[1] = '\0';
  276. break;
  277. }
  278. }
  279. puts(s);
  280. }
  281. static void center(char *str, unsigned len, unsigned separate)
  282. {
  283. unsigned n = strlen(str);
  284. len -= n;
  285. printf("%*s%*s", (len/2) + n, str, (len/2) + (len % 2) + separate, "");
  286. }
  287. static void blank_string(char *buf, size_t buflen)
  288. {
  289. memset(buf, ' ', buflen);
  290. buf[buflen-1] = '\0';
  291. }
  292. static char *build_row(char *p, unsigned *dp)
  293. {
  294. unsigned col, val, day;
  295. memset(p, ' ', (julian + DAY_LEN) * 7);
  296. col = 0;
  297. do {
  298. day = *dp++;
  299. if (day != SPACE) {
  300. if (julian) {
  301. ++p;
  302. if (day >= 100) {
  303. *p = '0';
  304. p[-1] = (day / 100) + '0';
  305. day %= 100;
  306. }
  307. }
  308. val = day / 10;
  309. if (val > 0) {
  310. *p = val + '0';
  311. }
  312. *++p = day % 10 + '0';
  313. p += 2;
  314. } else {
  315. p += DAY_LEN + julian;
  316. }
  317. } while (++col < 7);
  318. return p;
  319. }
  320. /*
  321. * Copyright (c) 1989, 1993, 1994
  322. * The Regents of the University of California. All rights reserved.
  323. *
  324. * This code is derived from software contributed to Berkeley by
  325. * Kim Letkeman.
  326. *
  327. * Redistribution and use in source and binary forms, with or without
  328. * modification, are permitted provided that the following conditions
  329. * are met:
  330. * 1. Redistributions of source code must retain the above copyright
  331. * notice, this list of conditions and the following disclaimer.
  332. * 2. Redistributions in binary form must reproduce the above copyright
  333. * notice, this list of conditions and the following disclaimer in the
  334. * documentation and/or other materials provided with the distribution.
  335. * 3. Neither the name of the University nor the names of its contributors
  336. * may be used to endorse or promote products derived from this software
  337. * without specific prior written permission.
  338. *
  339. * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ''AS IS'' AND
  340. * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  341. * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  342. * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  343. * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  344. * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  345. * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  346. * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  347. * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  348. * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  349. * SUCH DAMAGE.
  350. */