1 /* $OpenBSD: cal.c,v 1.30 2015/10/09 01:37:06 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 <unistd.h> 45 46 #define THURSDAY 4 /* for reformation */ 47 #define SATURDAY 6 /* 1 Jan 1 was a Saturday */ 48 49 #define FIRST_MISSING_DAY 639799 /* 3 Sep 1752 */ 50 #define NUMBER_MISSING_DAYS 11 /* 11 day correction */ 51 52 #define MAXDAYS 42 /* max slots in a month array */ 53 #define SPACE -1 /* used in day array */ 54 55 static const int days_in_month[2][13] = { 56 {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}, 57 {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}, 58 }; 59 60 const int sep1752s[MAXDAYS] = { 61 SPACE, SPACE, 1, 2, 14, 15, 16, 62 17, 18, 19, 20, 21, 22, 23, 63 24, 25, 26, 27, 28, 29, 30, 64 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 65 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 66 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 67 }, sep1752m[MAXDAYS] = { 68 SPACE, 1, 2, 14, 15, 16, 17, 69 18, 19, 20, 21, 22, 23, 24, 70 25, 26, 27, 28, 29, 30, SPACE, 71 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 72 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 73 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 74 }, sep1752js[MAXDAYS] = { 75 SPACE, SPACE, 245, 246, 258, 259, 260, 76 261, 262, 263, 264, 265, 266, 267, 77 268, 269, 270, 271, 272, 273, 274, 78 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 79 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 80 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 81 }, sep1752jm[MAXDAYS] = { 82 SPACE, 245, 246, 258, 259, 260, 261, 83 262, 263, 264, 265, 266, 267, 268, 84 269, 270, 271, 272, 273, 274, SPACE, 85 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 86 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 87 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 88 }, empty[MAXDAYS] = { 89 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 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 }; 96 97 const char *month_names[12] = { 98 "January", "February", "March", "April", "May", "June", 99 "July", "August", "September", "October", "November", "December", 100 }; 101 102 #define DAY_HEADINGS_S "Su Mo Tu We Th Fr Sa" 103 #define DAY_HEADINGS_M "Mo Tu We Th Fr Sa Su" 104 #define DAY_HEADINGS_JS " Su Mo Tu We Th Fr Sa" 105 #define DAY_HEADINGS_JM " Mo Tu We Th Fr Sa Su" 106 107 const int *sep1752 = NULL; 108 const char *day_headings = NULL; 109 110 /* leap year -- account for gregorian reformation in 1752 */ 111 #define leap_year(yr) \ 112 ((yr) <= 1752 ? !((yr) % 4) : \ 113 (!((yr) % 4) && ((yr) % 100)) || !((yr) % 400)) 114 115 /* number of centuries since 1700, not inclusive */ 116 #define centuries_since_1700(yr) \ 117 ((yr) > 1700 ? (yr) / 100 - 17 : 0) 118 119 /* number of centuries since 1700 whose modulo of 400 is 0 */ 120 #define quad_centuries_since_1700(yr) \ 121 ((yr) > 1600 ? ((yr) - 1600) / 400 : 0) 122 123 /* number of leap years between year 1 and this year, not inclusive */ 124 #define leap_years_since_year_1(yr) \ 125 ((yr) / 4 - centuries_since_1700(yr) + quad_centuries_since_1700(yr)) 126 127 int julian; 128 int mflag = 0; 129 int wflag = 0; 130 131 void ascii_day(char *, int); 132 void center(const char *, int, int); 133 void day_array(int, int, int *); 134 int day_in_week(int, int, int); 135 int day_in_year(int, int, int); 136 int week(int, int, int); 137 int isoweek(int, int, int); 138 void j_yearly(int); 139 void monthly(int, int); 140 void trim_trailing_spaces(char *); 141 void usage(void); 142 void yearly(int); 143 int parsemonth(const char *); 144 145 int 146 main(int argc, char *argv[]) 147 { 148 struct tm *local_time; 149 time_t now; 150 int ch, month, year, yflag; 151 const char *errstr; 152 153 if (pledge("stdio", NULL) == -1) 154 err(1, "pledge"); 155 156 yflag = year = 0; 157 while ((ch = getopt(argc, argv, "jmwy")) != -1) 158 switch(ch) { 159 case 'j': 160 julian = 1; 161 break; 162 case 'm': 163 mflag = 1; 164 break; 165 case 'w': 166 wflag = 1; 167 break; 168 case 'y': 169 yflag = 1; 170 break; 171 case '?': 172 default: 173 usage(); 174 } 175 argc -= optind; 176 argv += optind; 177 178 if (julian && wflag) 179 usage(); 180 181 day_headings = DAY_HEADINGS_S; 182 sep1752 = sep1752s; 183 if (mflag && julian) { 184 sep1752 = sep1752jm; 185 day_headings = DAY_HEADINGS_JM; 186 } else if (mflag) { 187 sep1752 = sep1752m; 188 day_headings = DAY_HEADINGS_M; 189 } else if (julian) { 190 sep1752 = sep1752js; 191 day_headings = DAY_HEADINGS_JS; 192 } 193 194 month = 0; 195 switch(argc) { 196 case 2: 197 month = parsemonth(*argv++); 198 if (!month) 199 errx(1, "Unable to parse month"); 200 /* FALLTHROUGH */ 201 case 1: 202 if (argc == 1 && !isdigit((unsigned char)*argv[0])) { 203 month = parsemonth(*argv); 204 if (!month) 205 errx(1, "illegal year value: use 1-9999"); 206 (void)time(&now); 207 local_time = localtime(&now); 208 year = local_time->tm_year + 1900; 209 } else { 210 year = strtonum(*argv, 1, 9999, &errstr); 211 if (errstr) 212 errx(1, "illegal year value: use 1-9999"); 213 } 214 break; 215 case 0: 216 (void)time(&now); 217 local_time = localtime(&now); 218 year = local_time->tm_year + 1900; 219 if (!yflag) 220 month = local_time->tm_mon + 1; 221 break; 222 default: 223 usage(); 224 } 225 226 if (month) 227 monthly(month, year); 228 else if (julian) 229 j_yearly(year); 230 else 231 yearly(year); 232 exit(0); 233 } 234 235 #define DAY_LEN 3 /* 3 spaces per day */ 236 #define J_DAY_LEN 4 /* 4 spaces per day */ 237 #define WEEK_LEN 20 /* 7 * 3 - one space at the end */ 238 #define WEEKNUMBER_LEN 5 /* 5 spaces per week number */ 239 #define J_WEEK_LEN 27 /* 7 * 4 - one space at the end */ 240 #define HEAD_SEP 2 /* spaces between day headings */ 241 #define J_HEAD_SEP 2 242 243 int 244 week(int day, int month, int year) 245 { 246 int yearday; 247 int firstweekday; 248 int weekday; 249 int firstday; 250 int firstsunday; 251 int shift; 252 253 if (mflag) 254 return isoweek(day, month, year); 255 256 yearday = day_in_year(day, month, year); 257 firstweekday = day_in_week(1, 1, year) + 1; 258 weekday = day_in_week(day, month, year) + 1; 259 firstday = day_in_year(1, 1, year); 260 firstsunday = firstday + (8 - firstweekday); 261 262 shift = 1; 263 if (yearday < firstsunday) 264 return (1); 265 if (firstweekday > THURSDAY - 1) 266 shift = 2; 267 return ((((yearday + 1) - (weekday - 1)) / 7) + shift); 268 } 269 270 int 271 isoweek(int day, int month, int year) 272 { 273 /* http://www.tondering.dk/claus/cal/node8.html */ 274 int a, b, c, s, e, f, g, d, n; 275 276 a = month <= 2 ? year - 1 : year; 277 b = a/4 - a/100 + a/400; 278 c = (a-1)/4 - (a-1)/100 + (a-1)/400; 279 s = b - c; 280 if (month <= 2) { 281 e = 0; 282 f = day - 1 + 31 * (month-1); 283 } else { 284 e = s + 1; 285 f = day + ((153 * (month-3) + 2) / 5) + 58 + s; 286 } 287 g = (a + b) % 7; 288 d = (f + g - e) % 7; 289 n = f + 3 - d; 290 291 if (n < 0) 292 return 53 - (g - s) / 5; 293 else if (n > 364 + s) 294 return 1; 295 else 296 return n/7 + 1; 297 } 298 299 void 300 monthly(int month, int year) 301 { 302 int col, row, len, days[MAXDAYS], firstday; 303 char *p, lineout[30]; 304 305 day_array(month, year, days); 306 (void)snprintf(lineout, sizeof(lineout), "%s %d", 307 month_names[month - 1], year); 308 len = strlen(lineout); 309 (void)printf("%*s%s\n%s\n", 310 ((julian ? J_WEEK_LEN : WEEK_LEN) - len) / 2, "", 311 lineout, day_headings); 312 for (row = 0; row < 6; row++) { 313 firstday = SPACE; 314 for (col = 0, p = lineout; col < 7; col++, 315 p += julian ? J_DAY_LEN : DAY_LEN) { 316 if (firstday == SPACE && days[row * 7 + col] != SPACE) 317 firstday = days[row * 7 + col]; 318 ascii_day(p, days[row * 7 + col]); 319 } 320 *p = '\0'; 321 trim_trailing_spaces(lineout); 322 (void)printf("%-20s", lineout); 323 if (wflag && firstday != SPACE) 324 printf(" [%2d]", week(firstday, month, year)); 325 printf("\n"); 326 } 327 } 328 329 void 330 j_yearly(int year) 331 { 332 int col, *dp, i, month, row, which_cal; 333 int days[12][MAXDAYS]; 334 char *p, lineout[80]; 335 336 (void)snprintf(lineout, sizeof(lineout), "%d", year); 337 center(lineout, J_WEEK_LEN * 2 + J_HEAD_SEP, 0); 338 (void)printf("\n\n"); 339 for (i = 0; i < 12; i++) 340 day_array(i + 1, year, days[i]); 341 (void)memset(lineout, ' ', sizeof(lineout) - 1); 342 lineout[sizeof(lineout) - 1] = '\0'; 343 for (month = 0; month < 12; month += 2) { 344 center(month_names[month], J_WEEK_LEN, J_HEAD_SEP); 345 center(month_names[month + 1], J_WEEK_LEN, 0); 346 (void)printf("\n%s%*s%s\n", day_headings, 347 J_HEAD_SEP, "", day_headings); 348 349 for (row = 0; row < 6; row++) { 350 for (which_cal = 0; which_cal < 2; which_cal++) { 351 p = lineout + which_cal * (J_WEEK_LEN + 2); 352 dp = &days[month + which_cal][row * 7]; 353 for (col = 0; col < 7; col++, p += J_DAY_LEN) 354 ascii_day(p, *dp++); 355 } 356 *p = '\0'; 357 trim_trailing_spaces(lineout); 358 (void)printf("%s\n", lineout); 359 } 360 } 361 (void)printf("\n"); 362 } 363 364 void 365 yearly(int year) 366 { 367 int col, *dp, i, month, row, which_cal, week_len, wn, firstday; 368 int days[12][MAXDAYS]; 369 char *p, lineout[81]; 370 371 week_len = WEEK_LEN; 372 if (wflag) 373 week_len += WEEKNUMBER_LEN; 374 (void)snprintf(lineout, sizeof(lineout), "%d", year); 375 center(lineout, week_len * 3 + HEAD_SEP * 2, 0); 376 (void)printf("\n\n"); 377 for (i = 0; i < 12; i++) 378 day_array(i + 1, year, days[i]); 379 (void)memset(lineout, ' ', sizeof(lineout) - 1); 380 lineout[sizeof(lineout) - 1] = '\0'; 381 for (month = 0; month < 12; month += 3) { 382 center(month_names[month], week_len, HEAD_SEP); 383 center(month_names[month + 1], week_len, HEAD_SEP); 384 center(month_names[month + 2], week_len, 0); 385 (void)printf("\n%s%*s%s%*s%s\n", day_headings, 386 HEAD_SEP + (wflag ? WEEKNUMBER_LEN : 0), "", day_headings, 387 HEAD_SEP + (wflag ? WEEKNUMBER_LEN : 0), "", day_headings); 388 389 for (row = 0; row < 6; row++) { 390 for (which_cal = 0; which_cal < 3; which_cal++) { 391 p = lineout + which_cal * (week_len + 2); 392 393 dp = &days[month + which_cal][row * 7]; 394 firstday = SPACE; 395 for (col = 0; col < 7; col++, p += DAY_LEN) { 396 if (firstday == SPACE && *dp != SPACE) 397 firstday = *dp; 398 ascii_day(p, *dp++); 399 } 400 if (wflag && firstday != SPACE) { 401 wn = week(firstday, 402 month + which_cal + 1, year); 403 (void)snprintf(p, 5, "[%2d]", wn); 404 p += strlen(p); 405 *p = ' '; 406 } else 407 memset(p, ' ', 4); 408 } 409 *p = '\0'; 410 trim_trailing_spaces(lineout); 411 (void)printf("%s\n", lineout); 412 } 413 } 414 (void)printf("\n"); 415 } 416 417 /* 418 * day_array -- 419 * Fill in an array of 42 integers with a calendar. Assume for a moment 420 * that you took the (maximum) 6 rows in a calendar and stretched them 421 * out end to end. You would have 42 numbers or spaces. This routine 422 * builds that array for any month from Jan. 1 through Dec. 9999. 423 */ 424 void 425 day_array(int month, int year, int *days) 426 { 427 int day, dw, dm; 428 429 if (month == 9 && year == 1752) { 430 memmove(days, sep1752, MAXDAYS * sizeof(int)); 431 return; 432 } 433 memmove(days, empty, MAXDAYS * sizeof(int)); 434 dm = days_in_month[leap_year(year)][month]; 435 dw = day_in_week(mflag?0:1, month, year); 436 day = julian ? day_in_year(1, month, year) : 1; 437 while (dm--) 438 days[dw++] = day++; 439 } 440 441 /* 442 * day_in_year -- 443 * return the 1 based day number within the year 444 */ 445 int 446 day_in_year(int day, int month, int year) 447 { 448 int i, leap; 449 450 leap = leap_year(year); 451 for (i = 1; i < month; i++) 452 day += days_in_month[leap][i]; 453 return (day); 454 } 455 456 /* 457 * day_in_week 458 * return the 0 based day number for any date from 1 Jan. 1 to 459 * 31 Dec. 9999. Assumes the Gregorian reformation eliminates 460 * 3 Sep. 1752 through 13 Sep. 1752. Returns Thursday for all 461 * missing days. 462 */ 463 int 464 day_in_week(int day, int month, int year) 465 { 466 long temp; 467 468 temp = (long)(year - 1) * 365 + leap_years_since_year_1(year - 1) 469 + day_in_year(day, month, year); 470 if (temp < FIRST_MISSING_DAY) 471 return ((temp - 1 + SATURDAY) % 7); 472 if (temp >= (FIRST_MISSING_DAY + NUMBER_MISSING_DAYS)) 473 return (((temp - 1 + SATURDAY) - NUMBER_MISSING_DAYS) % 7); 474 return (THURSDAY); 475 } 476 477 void 478 ascii_day(char *p, int day) 479 { 480 int display, val; 481 static const char *aday[] = { 482 "", 483 " 1", " 2", " 3", " 4", " 5", " 6", " 7", 484 " 8", " 9", "10", "11", "12", "13", "14", 485 "15", "16", "17", "18", "19", "20", "21", 486 "22", "23", "24", "25", "26", "27", "28", 487 "29", "30", "31", 488 }; 489 490 if (day == SPACE) { 491 memset(p, ' ', julian ? J_DAY_LEN : DAY_LEN); 492 return; 493 } 494 if (julian) { 495 val = day / 100; 496 if (val) { 497 day %= 100; 498 *p++ = val + '0'; 499 display = 1; 500 } else { 501 *p++ = ' '; 502 display = 0; 503 } 504 val = day / 10; 505 if (val || display) 506 *p++ = val + '0'; 507 else 508 *p++ = ' '; 509 *p++ = day % 10 + '0'; 510 } else { 511 *p++ = aday[day][0]; 512 *p++ = aday[day][1]; 513 } 514 *p = ' '; 515 } 516 517 void 518 trim_trailing_spaces(char *s) 519 { 520 char *p; 521 522 for (p = s; *p; ++p) 523 continue; 524 while (p > s && isspace((unsigned char)*--p)) 525 continue; 526 if (p > s) 527 ++p; 528 *p = '\0'; 529 } 530 531 void 532 center(const char *str, int len, int separate) 533 { 534 535 len -= strlen(str); 536 (void)printf("%*s%s%*s", len / 2, "", str, 537 len / 2 + len % 2 + separate, ""); 538 } 539 540 void 541 usage(void) 542 { 543 544 (void)fprintf(stderr, "usage: cal [-jmwy] [month] [year]\n"); 545 exit(1); 546 } 547 548 int 549 parsemonth(const char *s) 550 { 551 struct tm tm; 552 char *cp; 553 int v; 554 555 v = (int)strtol(s, &cp, 10); 556 if (*cp != '\0') { /* s wasn't purely numeric */ 557 v = 0; 558 if ((cp = strptime(s, "%b", &tm)) != NULL && *cp == '\0') 559 v = tm.tm_mon + 1; 560 } 561 if (v <= 0 || v > 12) 562 errx(1, "invalid month: use 1-12 or a name"); 563 return (v); 564 } 565