cal.c revision 1.1
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[] = "@(#)cal.c 5.2 (Berkeley) 4/19/91"; 45 #endif /* not lint */ 46 47 #include <sys/types.h> 48 #include <sys/time.h> 49 #include <stdio.h> 50 #include <ctype.h> 51 52 #define THURSDAY 4 /* for reformation */ 53 #define SATURDAY 6 /* 1 Jan 1 was a Saturday */ 54 55 #define FIRST_MISSING_DAY 639787 /* 3 Sep 1752 */ 56 #define NUMBER_MISSING_DAYS 11 /* 11 day correction */ 57 58 #define MAXDAYS 42 /* max slots in a month array */ 59 #define SPACE -1 /* used in day array */ 60 61 static int days_in_month[2][13] = { 62 {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}, 63 {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}, 64 }; 65 66 int sep1752[MAXDAYS] = { 67 SPACE, SPACE, 1, 2, 14, 15, 16, 68 17, 18, 19, 20, 21, 22, 23, 69 24, 25, 26, 27, 28, 29, 30, 70 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 71 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 72 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 73 }, j_sep1752[MAXDAYS] = { 74 SPACE, SPACE, 245, 246, 258, 259, 260, 75 261, 262, 263, 264, 265, 266, 267, 76 268, 269, 270, 271, 272, 273, 274, 77 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 78 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 79 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 80 }, empty[MAXDAYS] = { 81 SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, SPACE, 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 }; 88 89 char *month_names[12] = { 90 "January", "February", "March", "April", "May", "June", 91 "July", "August", "September", "October", "November", "December", 92 }; 93 94 char *day_headings = " S M Tu W Th F S"; 95 char *j_day_headings = " S M Tu W Th F S"; 96 97 /* leap year -- account for gregorian reformation in 1752 */ 98 #define leap_year(yr) \ 99 ((yr) <= 1752 ? !((yr) % 4) : \ 100 !((yr) % 4) && ((yr) % 100) || !((yr) % 400)) 101 102 /* number of centuries since 1700, not inclusive */ 103 #define centuries_since_1700(yr) \ 104 ((yr) > 1700 ? (yr) / 100 - 17 : 0) 105 106 /* number of centuries since 1700 whose modulo of 400 is 0 */ 107 #define quad_centuries_since_1700(yr) \ 108 ((yr) > 1600 ? ((yr) - 1600) / 400 : 0) 109 110 /* number of leap years between year 1 and this year, not inclusive */ 111 #define leap_years_since_year_1(yr) \ 112 ((yr) / 4 - centuries_since_1700(yr) + quad_centuries_since_1700(yr)) 113 114 int julian; 115 116 main(argc, argv) 117 int argc; 118 char **argv; 119 { 120 extern char *optarg; 121 extern int optind; 122 struct tm *local_time; 123 time_t now, time(); 124 int ch, month, year, yflag; 125 126 yflag = 0; 127 while ((ch = getopt(argc, argv, "jy")) != EOF) 128 switch(ch) { 129 case 'j': 130 julian = 1; 131 break; 132 case 'y': 133 yflag = 1; 134 break; 135 case '?': 136 default: 137 usage(); 138 } 139 argc -= optind; 140 argv += optind; 141 142 month = 0; 143 switch(argc) { 144 case 2: 145 if ((month = atoi(*argv++)) <= 0 || month > 12) { 146 (void)fprintf(stderr, 147 "cal: illegal month value: use 0-12\n"); 148 exit(1); 149 } 150 /* FALLTHROUGH */ 151 case 1: 152 if ((year = atoi(*argv)) <= 0 || year > 9999) { 153 (void)fprintf(stderr, 154 "cal: illegal year value: use 0-9999\n"); 155 exit(1); 156 } 157 break; 158 case 0: 159 (void)time(&now); 160 local_time = localtime(&now); 161 year = local_time->tm_year + 1900; 162 if (!yflag) 163 month = local_time->tm_mon + 1; 164 break; 165 default: 166 usage(); 167 } 168 169 if (month) 170 monthly(month, year); 171 else if (julian) 172 j_yearly(year); 173 else 174 yearly(year); 175 exit(0); 176 } 177 178 #define DAY_LEN 3 /* 3 spaces per day */ 179 #define J_DAY_LEN 4 /* 4 spaces per day */ 180 #define WEEK_LEN 20 /* 7 * 3 - one space at the end */ 181 #define J_WEEK_LEN 27 /* 7 * 4 - one space at the end */ 182 #define HEAD_SEP 2 /* spaces between day headings */ 183 #define J_HEAD_SEP 2 184 185 monthly(month, year) 186 int month, year; 187 { 188 register int col, row; 189 register char *p; 190 int len, days[MAXDAYS]; 191 char lineout[30]; 192 193 day_array(month, year, days); 194 len = sprintf(lineout, "%s %d", month_names[month - 1], year); 195 (void)printf("%*s%s\n%s\n", 196 ((julian ? J_WEEK_LEN : WEEK_LEN) - len) / 2, "", 197 lineout, julian ? j_day_headings : day_headings); 198 for (row = 0; row < 6; row++) { 199 for (col = 0, p = lineout; col < 7; col++, 200 p += julian ? J_DAY_LEN : DAY_LEN) 201 ascii_day(p, days[row * 7 + col]); 202 trim_trailing_spaces(lineout); 203 (void)printf("%s\n", lineout); 204 } 205 } 206 207 j_yearly(year) 208 int year; 209 { 210 register int col, *dp, i, month, row, which_cal; 211 register char *p; 212 int days[12][MAXDAYS]; 213 char lineout[80]; 214 215 (void)sprintf(lineout, "%d", year); 216 center(lineout, J_WEEK_LEN * 2 + J_HEAD_SEP, 0); 217 (void)printf("\n\n"); 218 for (i = 0; i < 12; i++) 219 day_array(i + 1, year, days[i]); 220 (void)memset(lineout, ' ', sizeof(lineout) - 1); 221 lineout[sizeof(lineout) - 1] = '\0'; 222 for (month = 0; month < 12; month += 2) { 223 center(month_names[month], J_WEEK_LEN, J_HEAD_SEP); 224 center(month_names[month + 1], J_WEEK_LEN, 0); 225 (void)printf("\n%s%*s%s\n", j_day_headings, J_HEAD_SEP, "", 226 j_day_headings); 227 for (row = 0; row < 6; row++) { 228 for (which_cal = 0; which_cal < 2; which_cal++) { 229 p = lineout + which_cal * (J_WEEK_LEN + 2); 230 dp = &days[month + which_cal][row * 7]; 231 for (col = 0; col < 7; col++, p += J_DAY_LEN) 232 ascii_day(p, *dp++); 233 } 234 trim_trailing_spaces(lineout); 235 (void)printf("%s\n", lineout); 236 } 237 } 238 (void)printf("\n"); 239 } 240 241 yearly(year) 242 int year; 243 { 244 register int col, *dp, i, month, row, which_cal; 245 register char *p; 246 int days[12][MAXDAYS]; 247 char lineout[80]; 248 249 (void)sprintf(lineout, "%d", year); 250 center(lineout, WEEK_LEN * 3 + HEAD_SEP * 2, 0); 251 (void)printf("\n\n"); 252 for (i = 0; i < 12; i++) 253 day_array(i + 1, year, days[i]); 254 (void)memset(lineout, ' ', sizeof(lineout) - 1); 255 lineout[sizeof(lineout) - 1] = '\0'; 256 for (month = 0; month < 12; month += 3) { 257 center(month_names[month], WEEK_LEN, HEAD_SEP); 258 center(month_names[month + 1], WEEK_LEN, HEAD_SEP); 259 center(month_names[month + 2], WEEK_LEN, 0); 260 (void)printf("\n%s%*s%s%*s%s\n", day_headings, HEAD_SEP, 261 "", day_headings, HEAD_SEP, "", day_headings); 262 for (row = 0; row < 6; row++) { 263 for (which_cal = 0; which_cal < 3; which_cal++) { 264 p = lineout + which_cal * (WEEK_LEN + 2); 265 dp = &days[month + which_cal][row * 7]; 266 for (col = 0; col < 7; col++, p += DAY_LEN) 267 ascii_day(p, *dp++); 268 } 269 trim_trailing_spaces(lineout); 270 (void)printf("%s\n", lineout); 271 } 272 } 273 (void)printf("\n"); 274 } 275 276 /* 277 * day_array -- 278 * Fill in an array of 42 integers with a calendar. Assume for a moment 279 * that you took the (maximum) 6 rows in a calendar and stretched them 280 * out end to end. You would have 42 numbers or spaces. This routine 281 * builds that array for any month from Jan. 1 through Dec. 9999. 282 */ 283 day_array(month, year, days) 284 register int *days; 285 int month, year; 286 { 287 register int i, day, dw, dm; 288 289 if (month == 9 && year == 1752) { 290 bcopy(julian ? j_sep1752 : sep1752, 291 days, MAXDAYS * sizeof(int)); 292 return; 293 } 294 bcopy(empty, days, MAXDAYS * sizeof(int)); 295 dm = days_in_month[leap_year(year)][month]; 296 dw = day_in_week(1, month, year); 297 day = julian ? day_in_year(1, month, year) : 1; 298 while (dm--) 299 days[dw++] = day++; 300 } 301 302 /* 303 * day_in_year -- 304 * return the 1 based day number within the year 305 */ 306 day_in_year(day, month, year) 307 register int day, month; 308 int year; 309 { 310 register int i, leap; 311 312 leap = leap_year(year); 313 for (i = 1; i < month; i++) 314 day += days_in_month[leap][i]; 315 return(day); 316 } 317 318 /* 319 * day_in_week 320 * return the 0 based day number for any date from 1 Jan. 1 to 321 * 31 Dec. 9999. Assumes the Gregorian reformation eliminates 322 * 3 Sep. 1752 through 13 Sep. 1752. Returns Thursday for all 323 * missing days. 324 */ 325 day_in_week(day, month, year) 326 int day, month, year; 327 { 328 long temp; 329 330 temp = (long)(year - 1) * 365 + leap_years_since_year_1(year - 1) 331 + day_in_year(day, month, year); 332 if (temp < FIRST_MISSING_DAY) 333 return((temp - 1 + SATURDAY) % 7); 334 if (temp >= (FIRST_MISSING_DAY + NUMBER_MISSING_DAYS)) 335 return(((temp - 1 + SATURDAY) - NUMBER_MISSING_DAYS) % 7); 336 return(THURSDAY); 337 } 338 339 ascii_day(p, day) 340 register char *p; 341 register int day; 342 { 343 register int display, val; 344 static char *aday[] = { 345 "", 346 " 1", " 2", " 3", " 4", " 5", " 6", " 7", 347 " 8", " 9", "10", "11", "12", "13", "14", 348 "15", "16", "17", "18", "19", "20", "21", 349 "22", "23", "24", "25", "26", "27", "28", 350 "29", "30", "31", 351 }; 352 353 if (day == SPACE) { 354 memset(p, ' ', julian ? J_DAY_LEN : DAY_LEN); 355 return; 356 } 357 if (julian) { 358 if (val = day / 100) { 359 day %= 100; 360 *p++ = val + '0'; 361 display = 1; 362 } else { 363 *p++ = ' '; 364 display = 0; 365 } 366 val = day / 10; 367 if (val || display) 368 *p++ = val + '0'; 369 else 370 *p++ = ' '; 371 *p++ = day % 10 + '0'; 372 } else { 373 *p++ = aday[day][0]; 374 *p++ = aday[day][1]; 375 } 376 *p = ' '; 377 } 378 379 trim_trailing_spaces(s) 380 register char *s; 381 { 382 register char *p; 383 384 for (p = s; *p; ++p); 385 while (p > s && isspace(*--p)); 386 if (p > s) 387 ++p; 388 *p = '\0'; 389 } 390 391 center(str, len, separate) 392 char *str; 393 register int len; 394 int separate; 395 { 396 len -= strlen(str); 397 (void)printf("%*s%s%*s", len / 2, "", str, len / 2 + len % 2, ""); 398 if (separate) 399 (void)printf("%*s", separate, ""); 400 } 401 402 usage() 403 { 404 (void)fprintf(stderr, "usage: cal [-jy] [[month] year]\n"); 405 exit(1); 406 } 407
Indexes created Tue Sep 30 20:09:53 GMT 2025