cal.c revision 1.12
1 /* $NetBSD: cal.c,v 1.12 2002/06/21 19:58:48 perry Exp $ */ 2 3 /* 4 * Copyright (c) 1989, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Kim Letkeman. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 #ifndef lint 41 __COPYRIGHT("@(#) Copyright (c) 1989, 1993, 1994\n\ 42 The Regents of the University of California. All rights reserved.\n"); 43 #endif /* not lint */ 44 45 #ifndef lint 46 #if 0 47 static char sccsid[] = "@(#)cal.c 8.4 (Berkeley) 4/2/94"; 48 #else 49 __RCSID("$NetBSD: cal.c,v 1.12 2002/06/21 19:58:48 perry Exp $"); 50 #endif 51 #endif /* not lint */ 52 53 #include <sys/types.h> 54 55 #include <ctype.h> 56 #include <err.h> 57 #include <stdio.h> 58 #include <stdlib.h> 59 #include <string.h> 60 #include <time.h> 61 #include <tzfile.h> 62 #include <unistd.h> 63 64 #define THURSDAY 4 /* for reformation */ 65 #define SATURDAY 6 /* 1 Jan 1 was a Saturday */ 66 67 #define FIRST_MISSING_DAY 639799 /* 3 Sep 1752 */ 68 #define NUMBER_MISSING_DAYS 11 /* 11 day correction */ 69 70 #define MAXDAYS 42 /* max slots in a month array */ 71 #define SPACE -1 /* used in day array */ 72 73 static int days_in_month[2][13] = { 74 {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}, 75 {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}, 76 }; 77 78 int sep1752[MAXDAYS] = { 79 SPACE, SPACE, 1, 2, 14, 15, 16, 80 17, 18, 19, 20, 21, 22, 23, 81 24, 25, 26, 27, 28, 29, 30, 82 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 83 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 84 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 85 }, j_sep1752[MAXDAYS] = { 86 SPACE, SPACE, 245, 246, 258, 259, 260, 87 261, 262, 263, 264, 265, 266, 267, 88 268, 269, 270, 271, 272, 273, 274, 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 }, empty[MAXDAYS] = { 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 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 97 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 98 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 99 }; 100 101 char *month_names[12] = { 102 "January", "February", "March", "April", "May", "June", 103 "July", "August", "September", "October", "November", "December", 104 }; 105 106 char *day_headings = " S M Tu W Th F S"; 107 char *j_day_headings = " S M Tu W Th F S"; 108 109 /* leap year -- account for gregorian reformation in 1752 */ 110 #define leap_year(yr) \ 111 ((yr) <= 1752 ? !((yr) % 4) : \ 112 (!((yr) % 4) && ((yr) % 100)) || !((yr) % 400)) 113 114 /* number of centuries since 1700, not inclusive */ 115 #define centuries_since_1700(yr) \ 116 ((yr) > 1700 ? (yr) / 100 - 17 : 0) 117 118 /* number of centuries since 1700 whose modulo of 400 is 0 */ 119 #define quad_centuries_since_1700(yr) \ 120 ((yr) > 1600 ? ((yr) - 1600) / 400 : 0) 121 122 /* number of leap years between year 1 and this year, not inclusive */ 123 #define leap_years_since_year_1(yr) \ 124 ((yr) / 4 - centuries_since_1700(yr) + quad_centuries_since_1700(yr)) 125 126 int julian; 127 128 void ascii_day(char *, int); 129 void center(char *, int, int); 130 void day_array(int, int, int *); 131 int day_in_week(int, int, int); 132 int day_in_year(int, int, int); 133 void j_yearly(int); 134 void monthly(int, int); 135 int main(int, char **); 136 void trim_trailing_spaces(char *); 137 void usage(void); 138 void yearly(int); 139 140 int 141 main(int argc, char **argv) 142 { 143 struct tm *local_time; 144 time_t now; 145 int ch, month, year, yflag; 146 147 yflag = year = 0; 148 while ((ch = getopt(argc, argv, "jy")) != -1) { 149 switch (ch) { 150 case 'j': 151 julian = 1; 152 break; 153 case 'y': 154 yflag = 1; 155 break; 156 case '?': 157 default: 158 usage(); 159 /* NOTREACHED */ 160 } 161 } 162 argc -= optind; 163 argv += optind; 164 165 month = 0; 166 switch (argc) { 167 case 2: 168 if ((month = atoi(*argv++)) < 1 || month > 12) 169 errx(1, "illegal month value: use 1-12"); 170 /* FALLTHROUGH */ 171 case 1: 172 if ((year = atoi(*argv)) < 1 || year > 9999) 173 errx(1, "illegal year value: use 1-9999"); 174 break; 175 case 0: 176 (void)time(&now); 177 local_time = localtime(&now); 178 year = local_time->tm_year + TM_YEAR_BASE; 179 if (!yflag) 180 month = local_time->tm_mon + 1; 181 break; 182 default: 183 usage(); 184 } 185 186 if (month) 187 monthly(month, year); 188 else if (julian) 189 j_yearly(year); 190 else 191 yearly(year); 192 exit(0); 193 } 194 195 #define DAY_LEN 3 /* 3 spaces per day */ 196 #define J_DAY_LEN 4 /* 4 spaces per day */ 197 #define WEEK_LEN 20 /* 7 * 3 - one space at the end */ 198 #define J_WEEK_LEN 27 /* 7 * 4 - one space at the end */ 199 #define HEAD_SEP 2 /* spaces between day headings */ 200 #define J_HEAD_SEP 2 201 202 void 203 monthly(int month, int year) 204 { 205 int col, row, len, days[MAXDAYS]; 206 char *p, lineout[30]; 207 208 day_array(month, year, days); 209 len = snprintf(lineout, sizeof(lineout), "%s %d", 210 month_names[month - 1], year); 211 (void)printf("%*s%s\n%s\n", 212 ((julian ? J_WEEK_LEN : WEEK_LEN) - len) / 2, "", 213 lineout, julian ? j_day_headings : day_headings); 214 for (row = 0; row < 6; row++) { 215 for (col = 0, p = lineout; col < 7; col++, 216 p += julian ? J_DAY_LEN : DAY_LEN) 217 ascii_day(p, days[row * 7 + col]); 218 *p = '\0'; 219 trim_trailing_spaces(lineout); 220 (void)printf("%s\n", lineout); 221 } 222 } 223 224 void 225 j_yearly(int year) 226 { 227 int col, *dp, i, month, row, which_cal; 228 int days[12][MAXDAYS]; 229 char *p, lineout[80]; 230 231 (void)snprintf(lineout, sizeof(lineout), "%d", year); 232 center(lineout, J_WEEK_LEN * 2 + J_HEAD_SEP, 0); 233 (void)printf("\n\n"); 234 for (i = 0; i < 12; i++) 235 day_array(i + 1, year, days[i]); 236 (void)memset(lineout, ' ', sizeof(lineout) - 1); 237 lineout[sizeof(lineout) - 1] = '\0'; 238 for (month = 0; month < 12; month += 2) { 239 center(month_names[month], J_WEEK_LEN, J_HEAD_SEP); 240 center(month_names[month + 1], J_WEEK_LEN, 0); 241 (void)printf("\n%s%*s%s\n", j_day_headings, J_HEAD_SEP, "", 242 j_day_headings); 243 for (row = 0; row < 6; row++) { 244 for (which_cal = 0; which_cal < 2; which_cal++) { 245 p = lineout + which_cal * (J_WEEK_LEN + 2); 246 dp = &days[month + which_cal][row * 7]; 247 for (col = 0; col < 7; col++, p += J_DAY_LEN) 248 ascii_day(p, *dp++); 249 } 250 *p = '\0'; 251 trim_trailing_spaces(lineout); 252 (void)printf("%s\n", lineout); 253 } 254 } 255 (void)printf("\n"); 256 } 257 258 void 259 yearly(int year) 260 { 261 int col, *dp, i, month, row, which_cal; 262 int days[12][MAXDAYS]; 263 char *p, lineout[80]; 264 265 (void)snprintf(lineout, sizeof(lineout), "%d", year); 266 center(lineout, WEEK_LEN * 3 + HEAD_SEP * 2, 0); 267 (void)printf("\n\n"); 268 for (i = 0; i < 12; i++) 269 day_array(i + 1, year, days[i]); 270 (void)memset(lineout, ' ', sizeof(lineout) - 1); 271 lineout[sizeof(lineout) - 1] = '\0'; 272 for (month = 0; month < 12; month += 3) { 273 center(month_names[month], WEEK_LEN, HEAD_SEP); 274 center(month_names[month + 1], WEEK_LEN, HEAD_SEP); 275 center(month_names[month + 2], WEEK_LEN, 0); 276 (void)printf("\n%s%*s%s%*s%s\n", day_headings, HEAD_SEP, 277 "", day_headings, HEAD_SEP, "", day_headings); 278 for (row = 0; row < 6; row++) { 279 for (which_cal = 0; which_cal < 3; which_cal++) { 280 p = lineout + which_cal * (WEEK_LEN + 2); 281 dp = &days[month + which_cal][row * 7]; 282 for (col = 0; col < 7; col++, p += DAY_LEN) 283 ascii_day(p, *dp++); 284 } 285 *p = '\0'; 286 trim_trailing_spaces(lineout); 287 (void)printf("%s\n", lineout); 288 } 289 } 290 (void)printf("\n"); 291 } 292 293 /* 294 * day_array -- 295 * Fill in an array of 42 integers with a calendar. Assume for a moment 296 * that you took the (maximum) 6 rows in a calendar and stretched them 297 * out end to end. You would have 42 numbers or spaces. This routine 298 * builds that array for any month from Jan. 1 through Dec. 9999. 299 */ 300 void 301 day_array(int month, int year, int *days) 302 { 303 int day, dw, dm; 304 305 if (month == 9 && year == 1752) { 306 memmove(days, 307 julian ? j_sep1752 : sep1752, MAXDAYS * sizeof(int)); 308 return; 309 } 310 memmove(days, empty, MAXDAYS * sizeof(int)); 311 dm = days_in_month[leap_year(year)][month]; 312 dw = day_in_week(1, month, year); 313 day = julian ? day_in_year(1, month, year) : 1; 314 while (dm--) 315 days[dw++] = day++; 316 } 317 318 /* 319 * day_in_year -- 320 * return the 1 based day number within the year 321 */ 322 int 323 day_in_year(int day, int month, int year) 324 { 325 int i, leap; 326 327 leap = leap_year(year); 328 for (i = 1; i < month; i++) 329 day += days_in_month[leap][i]; 330 return (day); 331 } 332 333 /* 334 * day_in_week 335 * return the 0 based day number for any date from 1 Jan. 1 to 336 * 31 Dec. 9999. Assumes the Gregorian reformation eliminates 337 * 3 Sep. 1752 through 13 Sep. 1752. Returns Thursday for all 338 * missing days. 339 */ 340 int 341 day_in_week(int day, int month, int year) 342 { 343 long temp; 344 345 temp = (long)(year - 1) * 365 + leap_years_since_year_1(year - 1) 346 + day_in_year(day, month, year); 347 if (temp < FIRST_MISSING_DAY) 348 return ((temp - 1 + SATURDAY) % 7); 349 if (temp >= (FIRST_MISSING_DAY + NUMBER_MISSING_DAYS)) 350 return (((temp - 1 + SATURDAY) - NUMBER_MISSING_DAYS) % 7); 351 return (THURSDAY); 352 } 353 354 void 355 ascii_day(char *p, int day) 356 { 357 int display, val; 358 static char *aday[] = { 359 "", 360 " 1", " 2", " 3", " 4", " 5", " 6", " 7", 361 " 8", " 9", "10", "11", "12", "13", "14", 362 "15", "16", "17", "18", "19", "20", "21", 363 "22", "23", "24", "25", "26", "27", "28", 364 "29", "30", "31", 365 }; 366 367 if (day == SPACE) { 368 memset(p, ' ', julian ? J_DAY_LEN : DAY_LEN); 369 return; 370 } 371 if (julian) { 372 if ((val = day / 100) != 0) { 373 day %= 100; 374 *p++ = val + '0'; 375 display = 1; 376 } else { 377 *p++ = ' '; 378 display = 0; 379 } 380 val = day / 10; 381 if (val || display) 382 *p++ = val + '0'; 383 else 384 *p++ = ' '; 385 *p++ = day % 10 + '0'; 386 } else { 387 *p++ = aday[day][0]; 388 *p++ = aday[day][1]; 389 } 390 *p = ' '; 391 } 392 393 void 394 trim_trailing_spaces(char *s) 395 { 396 char *p; 397 398 for (p = s; *p; ++p) 399 continue; 400 while (p > s && isspace((unsigned char)*--p)) 401 continue; 402 if (p > s) 403 ++p; 404 *p = '\0'; 405 } 406 407 void 408 center(char *str, int len, int separate) 409 { 410 411 len -= strlen(str); 412 (void)printf("%*s%s%*s", len / 2, "", str, len / 2 + len % 2, ""); 413 if (separate) 414 (void)printf("%*s", separate, ""); 415 } 416 417 void 418 usage(void) 419 { 420 421 (void)fprintf(stderr, "usage: cal [-jy] [[month] year]\n"); 422 exit(1); 423 } 424
Indexes created Tue Sep 30 11:09:46 GMT 2025