cal.c revision 1.2
1 /* 2 * Copyright (c) 1989 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Kim Letkeman. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #ifndef lint 38 char copyright[] = 39 "@(#) Copyright (c) 1989 The Regents of the University of California.\n\ 40 All rights reserved.\n"; 41 #endif /* not lint */ 42 43 #ifndef lint 44 /*static char sccsid[] = "from: @(#)cal.c 5.2 (Berkeley) 4/19/91";*/ 45 static char rcsid[] = "$Id: cal.c,v 1.2 1993/08/01 18:18:17 mycroft Exp $"; 46 #endif /* not lint */ 47 48 #include <sys/types.h> 49 #include <sys/time.h> 50 #include <stdio.h> 51 #include <ctype.h> 52 53 #define THURSDAY 4 /* for reformation */ 54 #define SATURDAY 6 /* 1 Jan 1 was a Saturday */ 55 56 #define FIRST_MISSING_DAY 639787 /* 3 Sep 1752 */ 57 #define NUMBER_MISSING_DAYS 11 /* 11 day correction */ 58 59 #define MAXDAYS 42 /* max slots in a month array */ 60 #define SPACE -1 /* used in day array */ 61 62 static int days_in_month[2][13] = { 63 {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}, 64 {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}, 65 }; 66 67 int sep1752[MAXDAYS] = { 68 SPACE, SPACE, 1, 2, 14, 15, 16, 69 17, 18, 19, 20, 21, 22, 23, 70 24, 25, 26, 27, 28, 29, 30, 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 }, j_sep1752[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 }, empty[MAXDAYS] = { 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 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 86 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 87 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 88 }; 89 90 char *month_names[12] = { 91 "January", "February", "March", "April", "May", "June", 92 "July", "August", "September", "October", "November", "December", 93 }; 94 95 char *day_headings = " S M Tu W Th F S"; 96 char *j_day_headings = " S M Tu W Th F S"; 97 98 /* leap year -- account for gregorian reformation in 1752 */ 99 #define leap_year(yr) \ 100 ((yr) <= 1752 ? !((yr) % 4) : \ 101 !((yr) % 4) && ((yr) % 100) || !((yr) % 400)) 102 103 /* number of centuries since 1700, not inclusive */ 104 #define centuries_since_1700(yr) \ 105 ((yr) > 1700 ? (yr) / 100 - 17 : 0) 106 107 /* number of centuries since 1700 whose modulo of 400 is 0 */ 108 #define quad_centuries_since_1700(yr) \ 109 ((yr) > 1600 ? ((yr) - 1600) / 400 : 0) 110 111 /* number of leap years between year 1 and this year, not inclusive */ 112 #define leap_years_since_year_1(yr) \ 113 ((yr) / 4 - centuries_since_1700(yr) + quad_centuries_since_1700(yr)) 114 115 int julian; 116 117 main(argc, argv) 118 int argc; 119 char **argv; 120 { 121 extern char *optarg; 122 extern int optind; 123 struct tm *local_time; 124 time_t now, time(); 125 int ch, month, year, yflag; 126 127 yflag = 0; 128 while ((ch = getopt(argc, argv, "jy")) != EOF) 129 switch(ch) { 130 case 'j': 131 julian = 1; 132 break; 133 case 'y': 134 yflag = 1; 135 break; 136 case '?': 137 default: 138 usage(); 139 } 140 argc -= optind; 141 argv += optind; 142 143 month = 0; 144 switch(argc) { 145 case 2: 146 if ((month = atoi(*argv++)) <= 0 || month > 12) { 147 (void)fprintf(stderr, 148 "cal: illegal month value: use 0-12\n"); 149 exit(1); 150 } 151 /* FALLTHROUGH */ 152 case 1: 153 if ((year = atoi(*argv)) <= 0 || year > 9999) { 154 (void)fprintf(stderr, 155 "cal: illegal year value: use 0-9999\n"); 156 exit(1); 157 } 158 break; 159 case 0: 160 (void)time(&now); 161 local_time = localtime(&now); 162 year = local_time->tm_year + 1900; 163 if (!yflag) 164 month = local_time->tm_mon + 1; 165 break; 166 default: 167 usage(); 168 } 169 170 if (month) 171 monthly(month, year); 172 else if (julian) 173 j_yearly(year); 174 else 175 yearly(year); 176 exit(0); 177 } 178 179 #define DAY_LEN 3 /* 3 spaces per day */ 180 #define J_DAY_LEN 4 /* 4 spaces per day */ 181 #define WEEK_LEN 20 /* 7 * 3 - one space at the end */ 182 #define J_WEEK_LEN 27 /* 7 * 4 - one space at the end */ 183 #define HEAD_SEP 2 /* spaces between day headings */ 184 #define J_HEAD_SEP 2 185 186 monthly(month, year) 187 int month, year; 188 { 189 register int col, row; 190 register char *p; 191 int len, days[MAXDAYS]; 192 char lineout[30]; 193 194 day_array(month, year, days); 195 len = sprintf(lineout, "%s %d", month_names[month - 1], year); 196 (void)printf("%*s%s\n%s\n", 197 ((julian ? J_WEEK_LEN : WEEK_LEN) - len) / 2, "", 198 lineout, julian ? j_day_headings : day_headings); 199 for (row = 0; row < 6; row++) { 200 for (col = 0, p = lineout; col < 7; col++, 201 p += julian ? J_DAY_LEN : DAY_LEN) 202 ascii_day(p, days[row * 7 + col]); 203 trim_trailing_spaces(lineout); 204 (void)printf("%s\n", lineout); 205 } 206 } 207 208 j_yearly(year) 209 int year; 210 { 211 register int col, *dp, i, month, row, which_cal; 212 register char *p; 213 int days[12][MAXDAYS]; 214 char lineout[80]; 215 216 (void)sprintf(lineout, "%d", year); 217 center(lineout, J_WEEK_LEN * 2 + J_HEAD_SEP, 0); 218 (void)printf("\n\n"); 219 for (i = 0; i < 12; i++) 220 day_array(i + 1, year, days[i]); 221 (void)memset(lineout, ' ', sizeof(lineout) - 1); 222 lineout[sizeof(lineout) - 1] = '\0'; 223 for (month = 0; month < 12; month += 2) { 224 center(month_names[month], J_WEEK_LEN, J_HEAD_SEP); 225 center(month_names[month + 1], J_WEEK_LEN, 0); 226 (void)printf("\n%s%*s%s\n", j_day_headings, J_HEAD_SEP, "", 227 j_day_headings); 228 for (row = 0; row < 6; row++) { 229 for (which_cal = 0; which_cal < 2; which_cal++) { 230 p = lineout + which_cal * (J_WEEK_LEN + 2); 231 dp = &days[month + which_cal][row * 7]; 232 for (col = 0; col < 7; col++, p += J_DAY_LEN) 233 ascii_day(p, *dp++); 234 } 235 trim_trailing_spaces(lineout); 236 (void)printf("%s\n", lineout); 237 } 238 } 239 (void)printf("\n"); 240 } 241 242 yearly(year) 243 int year; 244 { 245 register int col, *dp, i, month, row, which_cal; 246 register char *p; 247 int days[12][MAXDAYS]; 248 char lineout[80]; 249 250 (void)sprintf(lineout, "%d", year); 251 center(lineout, WEEK_LEN * 3 + HEAD_SEP * 2, 0); 252 (void)printf("\n\n"); 253 for (i = 0; i < 12; i++) 254 day_array(i + 1, year, days[i]); 255 (void)memset(lineout, ' ', sizeof(lineout) - 1); 256 lineout[sizeof(lineout) - 1] = '\0'; 257 for (month = 0; month < 12; month += 3) { 258 center(month_names[month], WEEK_LEN, HEAD_SEP); 259 center(month_names[month + 1], WEEK_LEN, HEAD_SEP); 260 center(month_names[month + 2], WEEK_LEN, 0); 261 (void)printf("\n%s%*s%s%*s%s\n", day_headings, HEAD_SEP, 262 "", day_headings, HEAD_SEP, "", day_headings); 263 for (row = 0; row < 6; row++) { 264 for (which_cal = 0; which_cal < 3; which_cal++) { 265 p = lineout + which_cal * (WEEK_LEN + 2); 266 dp = &days[month + which_cal][row * 7]; 267 for (col = 0; col < 7; col++, p += DAY_LEN) 268 ascii_day(p, *dp++); 269 } 270 trim_trailing_spaces(lineout); 271 (void)printf("%s\n", lineout); 272 } 273 } 274 (void)printf("\n"); 275 } 276 277 /* 278 * day_array -- 279 * Fill in an array of 42 integers with a calendar. Assume for a moment 280 * that you took the (maximum) 6 rows in a calendar and stretched them 281 * out end to end. You would have 42 numbers or spaces. This routine 282 * builds that array for any month from Jan. 1 through Dec. 9999. 283 */ 284 day_array(month, year, days) 285 register int *days; 286 int month, year; 287 { 288 register int i, day, dw, dm; 289 290 if (month == 9 && year == 1752) { 291 bcopy(julian ? j_sep1752 : sep1752, 292 days, MAXDAYS * sizeof(int)); 293 return; 294 } 295 bcopy(empty, days, MAXDAYS * sizeof(int)); 296 dm = days_in_month[leap_year(year)][month]; 297 dw = day_in_week(1, month, year); 298 day = julian ? day_in_year(1, month, year) : 1; 299 while (dm--) 300 days[dw++] = day++; 301 } 302 303 /* 304 * day_in_year -- 305 * return the 1 based day number within the year 306 */ 307 day_in_year(day, month, year) 308 register int day, month; 309 int year; 310 { 311 register int i, leap; 312 313 leap = leap_year(year); 314 for (i = 1; i < month; i++) 315 day += days_in_month[leap][i]; 316 return(day); 317 } 318 319 /* 320 * day_in_week 321 * return the 0 based day number for any date from 1 Jan. 1 to 322 * 31 Dec. 9999. Assumes the Gregorian reformation eliminates 323 * 3 Sep. 1752 through 13 Sep. 1752. Returns Thursday for all 324 * missing days. 325 */ 326 day_in_week(day, month, year) 327 int day, month, year; 328 { 329 long temp; 330 331 temp = (long)(year - 1) * 365 + leap_years_since_year_1(year - 1) 332 + day_in_year(day, month, year); 333 if (temp < FIRST_MISSING_DAY) 334 return((temp - 1 + SATURDAY) % 7); 335 if (temp >= (FIRST_MISSING_DAY + NUMBER_MISSING_DAYS)) 336 return(((temp - 1 + SATURDAY) - NUMBER_MISSING_DAYS) % 7); 337 return(THURSDAY); 338 } 339 340 ascii_day(p, day) 341 register char *p; 342 register int day; 343 { 344 register int display, val; 345 static char *aday[] = { 346 "", 347 " 1", " 2", " 3", " 4", " 5", " 6", " 7", 348 " 8", " 9", "10", "11", "12", "13", "14", 349 "15", "16", "17", "18", "19", "20", "21", 350 "22", "23", "24", "25", "26", "27", "28", 351 "29", "30", "31", 352 }; 353 354 if (day == SPACE) { 355 memset(p, ' ', julian ? J_DAY_LEN : DAY_LEN); 356 return; 357 } 358 if (julian) { 359 if (val = day / 100) { 360 day %= 100; 361 *p++ = val + '0'; 362 display = 1; 363 } else { 364 *p++ = ' '; 365 display = 0; 366 } 367 val = day / 10; 368 if (val || display) 369 *p++ = val + '0'; 370 else 371 *p++ = ' '; 372 *p++ = day % 10 + '0'; 373 } else { 374 *p++ = aday[day][0]; 375 *p++ = aday[day][1]; 376 } 377 *p = ' '; 378 } 379 380 trim_trailing_spaces(s) 381 register char *s; 382 { 383 register char *p; 384 385 for (p = s; *p; ++p); 386 while (p > s && isspace(*--p)); 387 if (p > s) 388 ++p; 389 *p = '\0'; 390 } 391 392 center(str, len, separate) 393 char *str; 394 register int len; 395 int separate; 396 { 397 len -= strlen(str); 398 (void)printf("%*s%s%*s", len / 2, "", str, len / 2 + len % 2, ""); 399 if (separate) 400 (void)printf("%*s", separate, ""); 401 } 402 403 usage() 404 { 405 (void)fprintf(stderr, "usage: cal [-jy] [[month] year]\n"); 406 exit(1); 407 } 408
Indexes created Tue Sep 30 20:09:53 GMT 2025