1 /* $OpenBSD: cal.c,v 1.25 2009/10/27 23:59:36 deraadt Exp $ */ 2 /* $NetBSD: cal.c,v 1.6 1995/03/26 03:10:24 glass Exp $ */ 3 4 /* 5 * Copyright (c) 1989, 1993, 1994 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * Kim Letkeman. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/types.h> 37 38 #include <ctype.h> 39 #include <err.h> 40 #include <stdio.h> 41 #include <stdlib.h> 42 #include <string.h> 43 #include <time.h> 44 #include <tzfile.h> 45 #include <unistd.h> 46 47 #define THURSDAY 4 /* for reformation */ 48 #define SATURDAY 6 /* 1 Jan 1 was a Saturday */ 49 50 #define FIRST_MISSING_DAY 639799 /* 3 Sep 1752 */ 51 #define NUMBER_MISSING_DAYS 11 /* 11 day correction */ 52 53 #define MAXDAYS 42 /* max slots in a month array */ 54 #define SPACE -1 /* used in day array */ 55 56 static const int days_in_month[2][13] = { 57 {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}, 58 {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}, 59 }; 60 61 const int sep1752s[MAXDAYS] = { 62 SPACE, SPACE, 1, 2, 14, 15, 16, 63 17, 18, 19, 20, 21, 22, 23, 64 24, 25, 26, 27, 28, 29, 30, 65 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 66 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 67 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 68 }, sep1752m[MAXDAYS] = { 69 SPACE, 1, 2, 14, 15, 16, 17, 70 18, 19, 20, 21, 22, 23, 24, 71 25, 26, 27, 28, 29, 30, SPACE, 72 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 73 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 74 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 75 }, sep1752js[MAXDAYS] = { 76 SPACE, SPACE, 245, 246, 258, 259, 260, 77 261, 262, 263, 264, 265, 266, 267, 78 268, 269, 270, 271, 272, 273, 274, 79 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 80 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 81 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 82 }, sep1752jm[MAXDAYS] = { 83 SPACE, 245, 246, 258, 259, 260, 261, 84 262, 263, 264, 265, 266, 267, 268, 85 269, 270, 271, 272, 273, 274, SPACE, 86 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 87 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 88 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 89 }, empty[MAXDAYS] = { 90 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 91 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 92 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 93 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 94 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 95 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 96 }; 97 98 const char *month_names[12] = { 99 "January", "February", "March", "April", "May", "June", 100 "July", "August", "September", "October", "November", "December", 101 }; 102 103 #define DAY_HEADINGS_S "Su Mo Tu We Th Fr Sa" 104 #define DAY_HEADINGS_M "Mo Tu We Th Fr Sa Su" 105 #define DAY_HEADINGS_JS " Su Mo Tu We Th Fr Sa" 106 #define DAY_HEADINGS_JM " Mo Tu We Th Fr Sa Su" 107 108 const int *sep1752 = NULL; 109 const char *day_headings = NULL; 110 111 /* leap year -- account for gregorian reformation in 1752 */ 112 #define leap_year(yr) \ 113 ((yr) <= 1752 ? !((yr) % 4) : \ 114 (!((yr) % 4) && ((yr) % 100)) || !((yr) % 400)) 115 116 /* number of centuries since 1700, not inclusive */ 117 #define centuries_since_1700(yr) \ 118 ((yr) > 1700 ? (yr) / 100 - 17 : 0) 119 120 /* number of centuries since 1700 whose modulo of 400 is 0 */ 121 #define quad_centuries_since_1700(yr) \ 122 ((yr) > 1600 ? ((yr) - 1600) / 400 : 0) 123 124 /* number of leap years between year 1 and this year, not inclusive */ 125 #define leap_years_since_year_1(yr) \ 126 ((yr) / 4 - centuries_since_1700(yr) + quad_centuries_since_1700(yr)) 127 128 int julian; 129 int mflag = 0; 130 int wflag = 0; 131 132 void ascii_day(char *, int); 133 void center(const char *, int, int); 134 void day_array(int, int, int *); 135 int day_in_week(int, int, int); 136 int day_in_year(int, int, int); 137 int week(int, int, int); 138 int isoweek(int, int, int); 139 void j_yearly(int); 140 void monthly(int, int); 141 void trim_trailing_spaces(char *); 142 void usage(void); 143 void yearly(int); 144 int parsemonth(const char *); 145 146 int 147 main(int argc, char *argv[]) 148 { 149 struct tm *local_time; 150 time_t now; 151 int ch, month, year, yflag; 152 const char *errstr; 153 154 yflag = year = 0; 155 while ((ch = getopt(argc, argv, "jmwy")) != -1) 156 switch(ch) { 157 case 'j': 158 julian = 1; 159 break; 160 case 'm': 161 mflag = 1; 162 break; 163 case 'w': 164 wflag = 1; 165 break; 166 case 'y': 167 yflag = 1; 168 break; 169 case '?': 170 default: 171 usage(); 172 } 173 argc -= optind; 174 argv += optind; 175 176 if (julian && wflag) 177 usage(); 178 179 day_headings = DAY_HEADINGS_S; 180 sep1752 = sep1752s; 181 if (mflag && julian) { 182 sep1752 = sep1752jm; 183 day_headings = DAY_HEADINGS_JM; 184 } else if (mflag) { 185 sep1752 = sep1752m; 186 day_headings = DAY_HEADINGS_M; 187 } else if (julian) { 188 sep1752 = sep1752js; 189 day_headings = DAY_HEADINGS_JS; 190 } 191 192 month = 0; 193 switch(argc) { 194 case 2: 195 month = parsemonth(*argv++); 196 if (!month) 197 errx(1, "Unable to parse month"); 198 /* FALLTHROUGH */ 199 case 1: 200 if (argc == 1 && !isdigit(*argv[0])) { 201 month = parsemonth(*argv); 202 if (!month) 203 errx(1, "illegal year value: use 1-9999"); 204 (void)time(&now); 205 local_time = localtime(&now); 206 year = local_time->tm_year + TM_YEAR_BASE; 207 } else { 208 year = strtonum(*argv, 1, 9999, &errstr); 209 if (errstr) 210 errx(1, "illegal year value: use 1-9999"); 211 } 212 break; 213 case 0: 214 (void)time(&now); 215 local_time = localtime(&now); 216 year = local_time->tm_year + TM_YEAR_BASE; 217 if (!yflag) 218 month = local_time->tm_mon + 1; 219 break; 220 default: 221 usage(); 222 } 223 224 if (month) 225 monthly(month, year); 226 else if (julian) 227 j_yearly(year); 228 else 229 yearly(year); 230 exit(0); 231 } 232 233 #define DAY_LEN 3 /* 3 spaces per day */ 234 #define J_DAY_LEN 4 /* 4 spaces per day */ 235 #define WEEK_LEN 20 /* 7 * 3 - one space at the end */ 236 #define WEEKNUMBER_LEN 5 /* 5 spaces per week number */ 237 #define J_WEEK_LEN 27 /* 7 * 4 - one space at the end */ 238 #define HEAD_SEP 2 /* spaces between day headings */ 239 #define J_HEAD_SEP 2 240 241 int 242 week(int day, int month, int year) 243 { 244 int yearday; 245 int firstweekday; 246 int weekday; 247 int firstday; 248 int firstsunday; 249 int shift; 250 251 if (mflag) 252 return isoweek(day, month, year); 253 254 yearday = day_in_year(day, month, year); 255 firstweekday = day_in_week(1, 1, year) + 1; 256 weekday = day_in_week(day, month, year) + 1; 257 firstday = day_in_year(1, 1, year); 258 firstsunday = firstday + (8 - firstweekday); 259 260 shift = 1; 261 if (yearday < firstsunday) 262 return (1); 263 if (firstweekday > THURSDAY - 1) 264 shift = 2; 265 return ((((yearday + 1) - (weekday - 1)) / 7) + shift); 266 } 267 268 int 269 isoweek(int day, int month, int year) 270 { 271 /* http://www.tondering.dk/claus/cal/node8.html */ 272 int a, b, c, s, e, f, g, d, n; 273 274 a = month <= 2 ? year - 1 : year; 275 b = a/4 - a/100 + a/400; 276 c = (a-1)/4 - (a-1)/100 + (a-1)/400; 277 s = b - c; 278 if (month <= 2) { 279 e = 0; 280 f = day - 1 + 31 * (month-1); 281 } else { 282 e = s + 1; 283 f = day + ((153 * (month-3) + 2) / 5) + 58 + s; 284 } 285 g = (a + b) % 7; 286 d = (f + g - e) % 7; 287 n = f + 3 - d; 288 289 if (n < 0) 290 return 53 - (g - s) / 5; 291 else if (n > 364 + s) 292 return 1; 293 else 294 return n/7 + 1; 295 } 296 297 void 298 monthly(int month, int year) 299 { 300 int col, row, len, days[MAXDAYS], firstday; 301 char *p, lineout[30]; 302 303 day_array(month, year, days); 304 (void)snprintf(lineout, sizeof(lineout), "%s %d", 305 month_names[month - 1], year); 306 len = strlen(lineout); 307 (void)printf("%*s%s\n%s\n", 308 ((julian ? J_WEEK_LEN : WEEK_LEN) - len) / 2, "", 309 lineout, day_headings); 310 for (row = 0; row < 6; row++) { 311 firstday = SPACE; 312 for (col = 0, p = lineout; col < 7; col++, 313 p += julian ? J_DAY_LEN : DAY_LEN) { 314 if (firstday == SPACE && days[row * 7 + col] != SPACE) 315 firstday = days[row * 7 + col]; 316 ascii_day(p, days[row * 7 + col]); 317 } 318 *p = '\0'; 319 trim_trailing_spaces(lineout); 320 (void)printf("%-20s", lineout); 321 if (wflag && firstday != SPACE) 322 printf(" [%2d]", week(firstday, month, year)); 323 printf("\n"); 324 } 325 } 326 327 void 328 j_yearly(int year) 329 { 330 int col, *dp, i, month, row, which_cal; 331 int days[12][MAXDAYS]; 332 char *p, lineout[80]; 333 334 (void)snprintf(lineout, sizeof(lineout), "%d", year); 335 center(lineout, J_WEEK_LEN * 2 + J_HEAD_SEP, 0); 336 (void)printf("\n\n"); 337 for (i = 0; i < 12; i++) 338 day_array(i + 1, year, days[i]); 339 (void)memset(lineout, ' ', sizeof(lineout) - 1); 340 lineout[sizeof(lineout) - 1] = '\0'; 341 for (month = 0; month < 12; month += 2) { 342 center(month_names[month], J_WEEK_LEN, J_HEAD_SEP); 343 center(month_names[month + 1], J_WEEK_LEN, 0); 344 (void)printf("\n%s%*s%s\n", day_headings, 345 J_HEAD_SEP, "", day_headings); 346 347 for (row = 0; row < 6; row++) { 348 for (which_cal = 0; which_cal < 2; which_cal++) { 349 p = lineout + which_cal * (J_WEEK_LEN + 2); 350 dp = &days[month + which_cal][row * 7]; 351 for (col = 0; col < 7; col++, p += J_DAY_LEN) 352 ascii_day(p, *dp++); 353 } 354 *p = '\0'; 355 trim_trailing_spaces(lineout); 356 (void)printf("%s\n", lineout); 357 } 358 } 359 (void)printf("\n"); 360 } 361 362 void 363 yearly(int year) 364 { 365 int col, *dp, i, month, row, which_cal, week_len, wn, firstday; 366 int days[12][MAXDAYS]; 367 char *p, lineout[81]; 368 369 week_len = WEEK_LEN; 370 if (wflag) 371 week_len += WEEKNUMBER_LEN; 372 (void)snprintf(lineout, sizeof(lineout), "%d", year); 373 center(lineout, week_len * 3 + HEAD_SEP * 2, 0); 374 (void)printf("\n\n"); 375 for (i = 0; i < 12; i++) 376 day_array(i + 1, year, days[i]); 377 (void)memset(lineout, ' ', sizeof(lineout) - 1); 378 lineout[sizeof(lineout) - 1] = '\0'; 379 for (month = 0; month < 12; month += 3) { 380 center(month_names[month], week_len, HEAD_SEP); 381 center(month_names[month + 1], week_len, HEAD_SEP); 382 center(month_names[month + 2], week_len, 0); 383 (void)printf("\n%s%*s%s%*s%s\n", day_headings, 384 HEAD_SEP + (wflag ? WEEKNUMBER_LEN : 0), "", day_headings, 385 HEAD_SEP + (wflag ? WEEKNUMBER_LEN : 0), "", day_headings); 386 387 for (row = 0; row < 6; row++) { 388 for (which_cal = 0; which_cal < 3; which_cal++) { 389 p = lineout + which_cal * (week_len + 2); 390 391 dp = &days[month + which_cal][row * 7]; 392 firstday = SPACE; 393 for (col = 0; col < 7; col++, p += DAY_LEN) { 394 if (firstday == SPACE && *dp != SPACE) 395 firstday = *dp; 396 ascii_day(p, *dp++); 397 } 398 if (wflag && firstday != SPACE) { 399 wn = week(firstday, 400 month + which_cal + 1, year); 401 (void)snprintf(p, 5, "[%2d]", wn); 402 p += strlen(p); 403 *p = ' '; 404 } else 405 memset(p, ' ', 4); 406 } 407 *p = '\0'; 408 trim_trailing_spaces(lineout); 409 (void)printf("%s\n", lineout); 410 } 411 } 412 (void)printf("\n"); 413 } 414 415 /* 416 * day_array -- 417 * Fill in an array of 42 integers with a calendar. Assume for a moment 418 * that you took the (maximum) 6 rows in a calendar and stretched them 419 * out end to end. You would have 42 numbers or spaces. This routine 420 * builds that array for any month from Jan. 1 through Dec. 9999. 421 */ 422 void 423 day_array(int month, int year, int *days) 424 { 425 int day, dw, dm; 426 427 if (month == 9 && year == 1752) { 428 memmove(days, sep1752, MAXDAYS * sizeof(int)); 429 return; 430 } 431 memmove(days, empty, MAXDAYS * sizeof(int)); 432 dm = days_in_month[leap_year(year)][month]; 433 dw = day_in_week(mflag?0:1, month, year); 434 day = julian ? day_in_year(1, month, year) : 1; 435 while (dm--) 436 days[dw++] = day++; 437 } 438 439 /* 440 * day_in_year -- 441 * return the 1 based day number within the year 442 */ 443 int 444 day_in_year(int day, int month, int year) 445 { 446 int i, leap; 447 448 leap = leap_year(year); 449 for (i = 1; i < month; i++) 450 day += days_in_month[leap][i]; 451 return (day); 452 } 453 454 /* 455 * day_in_week 456 * return the 0 based day number for any date from 1 Jan. 1 to 457 * 31 Dec. 9999. Assumes the Gregorian reformation eliminates 458 * 3 Sep. 1752 through 13 Sep. 1752. Returns Thursday for all 459 * missing days. 460 */ 461 int 462 day_in_week(int day, int month, int year) 463 { 464 long temp; 465 466 temp = (long)(year - 1) * 365 + leap_years_since_year_1(year - 1) 467 + day_in_year(day, month, year); 468 if (temp < FIRST_MISSING_DAY) 469 return ((temp - 1 + SATURDAY) % 7); 470 if (temp >= (FIRST_MISSING_DAY + NUMBER_MISSING_DAYS)) 471 return (((temp - 1 + SATURDAY) - NUMBER_MISSING_DAYS) % 7); 472 return (THURSDAY); 473 } 474 475 void 476 ascii_day(char *p, int day) 477 { 478 int display, val; 479 static const char *aday[] = { 480 "", 481 " 1", " 2", " 3", " 4", " 5", " 6", " 7", 482 " 8", " 9", "10", "11", "12", "13", "14", 483 "15", "16", "17", "18", "19", "20", "21", 484 "22", "23", "24", "25", "26", "27", "28", 485 "29", "30", "31", 486 }; 487 488 if (day == SPACE) { 489 memset(p, ' ', julian ? J_DAY_LEN : DAY_LEN); 490 return; 491 } 492 if (julian) { 493 val = day / 100; 494 if (val) { 495 day %= 100; 496 *p++ = val + '0'; 497 display = 1; 498 } else { 499 *p++ = ' '; 500 display = 0; 501 } 502 val = day / 10; 503 if (val || display) 504 *p++ = val + '0'; 505 else 506 *p++ = ' '; 507 *p++ = day % 10 + '0'; 508 } else { 509 *p++ = aday[day][0]; 510 *p++ = aday[day][1]; 511 } 512 *p = ' '; 513 } 514 515 void 516 trim_trailing_spaces(char *s) 517 { 518 char *p; 519 520 for (p = s; *p; ++p) 521 continue; 522 while (p > s && isspace(*--p)) 523 continue; 524 if (p > s) 525 ++p; 526 *p = '\0'; 527 } 528 529 void 530 center(const char *str, int len, int separate) 531 { 532 533 len -= strlen(str); 534 (void)printf("%*s%s%*s", len / 2, "", str, 535 len / 2 + len % 2 + separate, ""); 536 } 537 538 void 539 usage(void) 540 { 541 542 (void)fprintf(stderr, "usage: cal [-jmwy] [month] [year]\n"); 543 exit(1); 544 } 545 546 int 547 parsemonth(const char *s) 548 { 549 struct tm tm; 550 char *cp; 551 int v; 552 553 v = (int)strtol(s, &cp, 10); 554 if (*cp != '\0') { /* s wasn't purely numeric */ 555 v = 0; 556 if ((cp = strptime(s, "%b", &tm)) != NULL && *cp == '\0') 557 v = tm.tm_mon + 1; 558 } 559 if (v <= 0 || v > 12) 560 errx(1, "invalid month: use 1-12 or a name"); 561 return (v); 562 } 563