1 /*- 2 * Copyright (c) 1997 Brian Somers <brian@Awfulhak.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #ifndef lint 28 static const char rcsid[] = 29 "$FreeBSD$"; 30 #endif /* not lint */ 31 32 #include <err.h> 33 #include <time.h> 34 #include <string.h> 35 #include <stdlib.h> 36 #include "vary.h" 37 38 struct trans { 39 int val; 40 char *str; 41 }; 42 43 static struct trans trans_mon[] = { 44 { 1, "january" }, { 2, "february" }, { 3, "march" }, { 4, "april" }, 45 { 5, "may"}, { 6, "june" }, { 7, "july" }, { 8, "august" }, 46 { 9, "september" }, { 10, "october" }, { 11, "november" }, { 12, "december" }, 47 { -1, NULL } 48 }; 49 50 static struct trans trans_wday[] = { 51 { 0, "sunday" }, { 1, "monday" }, { 2, "tuesday" }, { 3, "wednesday" }, 52 { 4, "thursday" }, { 5, "friday" }, { 6, "saturday" }, 53 { -1, NULL } 54 }; 55 56 static char digits[] = "0123456789"; 57 static int adjhour(struct tm *, char, int, int); 58 59 static int 60 domktime(struct tm *t, char type) 61 { 62 time_t ret; 63 64 while ((ret = mktime(t)) == -1 && t->tm_year > 68 && t->tm_year < 138) 65 /* While mktime() fails, adjust by an hour */ 66 adjhour(t, type == '-' ? type : '+', 1, 0); 67 68 return ret; 69 } 70 71 static int 72 trans(const struct trans t[], const char *arg) 73 { 74 int f; 75 76 for (f = 0; t[f].val != -1; f++) 77 if (!strncasecmp(t[f].str, arg, 3) || 78 !strncasecmp(t[f].str, arg, strlen(t[f].str))) 79 return t[f].val; 80 81 return -1; 82 } 83 84 struct vary * 85 vary_append(struct vary *v, char *arg) 86 { 87 struct vary *result, **nextp; 88 89 if (v) { 90 result = v; 91 while (v->next) 92 v = v->next; 93 nextp = &v->next; 94 } else 95 nextp = &result; 96 97 if ((*nextp = (struct vary *)malloc(sizeof(struct vary))) == NULL) 98 err(1, "malloc"); 99 (*nextp)->arg = arg; 100 (*nextp)->next = NULL; 101 return result; 102 } 103 104 static int mdays[12] = { 31, 0, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }; 105 106 static int 107 daysinmonth(const struct tm *t) 108 { 109 int year; 110 111 year = t->tm_year + 1900; 112 113 if (t->tm_mon == 1) 114 if (!(year % 400)) 115 return 29; 116 else if (!(year % 100)) 117 return 28; 118 else if (!(year % 4)) 119 return 29; 120 else 121 return 28; 122 else if (t->tm_mon >= 0 && t->tm_mon < 12) 123 return mdays[t->tm_mon]; 124 125 return 0; 126 } 127 128 129 static int 130 adjyear(struct tm *t, char type, int val, int mk) 131 { 132 switch (type) { 133 case '+': 134 t->tm_year += val; 135 break; 136 case '-': 137 t->tm_year -= val; 138 break; 139 default: 140 t->tm_year = val; 141 if (t->tm_year < 69) 142 t->tm_year += 100; /* as per date.c */ 143 else if (t->tm_year > 1900) 144 t->tm_year -= 1900; /* struct tm holds years since 1900 */ 145 break; 146 } 147 return !mk || domktime(t, type) != -1; 148 } 149 150 static int 151 adjmon(struct tm *t, char type, int val, int istext, int mk) 152 { 153 if (val < 0) 154 return 0; 155 156 switch (type) { 157 case '+': 158 if (istext) { 159 if (val <= t->tm_mon) 160 val += 11 - t->tm_mon; /* early next year */ 161 else 162 val -= t->tm_mon + 1; /* later this year */ 163 } 164 if (val) { 165 if (!adjyear(t, '+', (t->tm_mon + val) / 12, 0)) 166 return 0; 167 val %= 12; 168 t->tm_mon += val; 169 if (t->tm_mon > 11) 170 t->tm_mon -= 12; 171 } 172 break; 173 174 case '-': 175 if (istext) { 176 if (val-1 > t->tm_mon) 177 val = 13 - val + t->tm_mon; /* later last year */ 178 else 179 val = t->tm_mon - val + 1; /* early this year */ 180 } 181 if (val) { 182 if (!adjyear(t, '-', val / 12, 0)) 183 return 0; 184 val %= 12; 185 if (val > t->tm_mon) { 186 if (!adjyear(t, '-', 1, 0)) 187 return 0; 188 val -= 12; 189 } 190 t->tm_mon -= val; 191 } 192 break; 193 194 default: 195 if (val > 12 || val < 1) 196 return 0; 197 t->tm_mon = --val; 198 } 199 200 return !mk || domktime(t, type) != -1; 201 } 202 203 static int 204 adjday(struct tm *t, char type, int val, int mk) 205 { 206 int mdays; 207 208 switch (type) { 209 case '+': 210 while (val) { 211 mdays = daysinmonth(t); 212 if (val > mdays - t->tm_mday) { 213 val -= mdays - t->tm_mday + 1; 214 t->tm_mday = 1; 215 if (!adjmon(t, '+', 1, 0, 0)) 216 return 0; 217 } else { 218 t->tm_mday += val; 219 val = 0; 220 } 221 } 222 break; 223 case '-': 224 while (val) 225 if (val >= t->tm_mday) { 226 val -= t->tm_mday; 227 t->tm_mday = 1; 228 if (!adjmon(t, '-', 1, 0, 0)) 229 return 0; 230 t->tm_mday = daysinmonth(t); 231 } else { 232 t->tm_mday -= val; 233 val = 0; 234 } 235 break; 236 default: 237 if (val > 0 && val <= daysinmonth(t)) 238 t->tm_mday = val; 239 else 240 return 0; 241 break; 242 } 243 244 return !mk || domktime(t, type) != -1; 245 } 246 247 static int 248 adjwday(struct tm *t, char type, int val, int istext, int mk) 249 { 250 if (val < 0) 251 return 0; 252 253 switch (type) { 254 case '+': 255 if (istext) 256 if (val < t->tm_wday) 257 val = 7 - t->tm_wday + val; /* early next week */ 258 else 259 val -= t->tm_wday; /* later this week */ 260 else 261 val *= 7; /* "-v+5w" == "5 weeks in the future" */ 262 return !val || adjday(t, '+', val, mk); 263 case '-': 264 if (istext) { 265 if (val > t->tm_wday) 266 val = 7 - val + t->tm_wday; /* later last week */ 267 else 268 val = t->tm_wday - val; /* early this week */ 269 } else 270 val *= 7; /* "-v-5w" == "5 weeks ago" */ 271 return !val || adjday(t, '-', val, mk); 272 default: 273 if (val < t->tm_wday) 274 return adjday(t, '-', t->tm_wday - val, mk); 275 else if (val > 6) 276 return 0; 277 else if (val > t->tm_wday) 278 return adjday(t, '+', val - t->tm_wday, mk); 279 } 280 return 1; 281 } 282 283 static int 284 adjhour(struct tm *t, char type, int val, int mk) 285 { 286 if (val < 0) 287 return 0; 288 289 switch (type) { 290 case '+': 291 if (val) { 292 int days; 293 294 days = (t->tm_hour + val) / 24; 295 val %= 24; 296 t->tm_hour += val; 297 t->tm_hour %= 24; 298 if (!adjday(t, '+', days, 0)) 299 return 0; 300 } 301 break; 302 303 case '-': 304 if (val) { 305 int days; 306 307 days = val / 24; 308 val %= 24; 309 if (val > t->tm_hour) { 310 days++; 311 val -= 24; 312 } 313 t->tm_hour -= val; 314 if (!adjday(t, '-', days, 0)) 315 return 0; 316 } 317 break; 318 319 default: 320 if (val > 23) 321 return 0; 322 t->tm_hour = val; 323 } 324 325 return !mk || domktime(t, type) != -1; 326 } 327 328 static int 329 adjmin(struct tm *t, char type, int val, int mk) 330 { 331 if (val < 0) 332 return 0; 333 334 switch (type) { 335 case '+': 336 if (val) { 337 if (!adjhour(t, '+', (t->tm_min + val) / 60, 0)) 338 return 0; 339 val %= 60; 340 t->tm_min += val; 341 if (t->tm_min > 59) 342 t->tm_min -= 60; 343 } 344 break; 345 346 case '-': 347 if (val) { 348 if (!adjhour(t, '-', val / 60, 0)) 349 return 0; 350 val %= 60; 351 if (val > t->tm_min) { 352 if (!adjhour(t, '-', 1, 0)) 353 return 0; 354 val -= 60; 355 } 356 t->tm_min -= val; 357 } 358 break; 359 360 default: 361 if (val > 59) 362 return 0; 363 t->tm_min = val; 364 } 365 366 return !mk || domktime(t, type) != -1; 367 } 368 369 static int 370 adjsec(struct tm *t, char type, int val, int mk) 371 { 372 if (val < 0) 373 return 0; 374 375 switch (type) { 376 case '+': 377 if (val) { 378 if (!adjmin(t, '+', (t->tm_sec + val) / 60, 0)) 379 return 0; 380 val %= 60; 381 t->tm_sec += val; 382 if (t->tm_sec > 59) 383 t->tm_sec -= 60; 384 } 385 break; 386 387 case '-': 388 if (val) { 389 if (!adjmin(t, '-', val / 60, 0)) 390 return 0; 391 val %= 60; 392 if (val > t->tm_sec) { 393 if (!adjmin(t, '-', 1, 0)) 394 return 0; 395 val -= 60; 396 } 397 t->tm_sec -= val; 398 } 399 break; 400 401 default: 402 if (val > 59) 403 return 0; 404 t->tm_sec = val; 405 } 406 407 return !mk || domktime(t, type) != -1; 408 } 409 410 const struct vary * 411 vary_apply(const struct vary *v, struct tm *t) 412 { 413 char type; 414 char which; 415 char *arg; 416 int len; 417 int val; 418 419 for (; v; v = v->next) { 420 type = *v->arg; 421 arg = v->arg; 422 if (type == '+' || type == '-') 423 arg++; 424 else 425 type = '\0'; 426 len = strlen(arg); 427 if (len < 2) 428 return v; 429 430 if (type == '\0') 431 t->tm_isdst = -1; 432 433 if (strspn(arg, digits) != len-1) { 434 val = trans(trans_wday, arg); 435 if (val != -1) { 436 if (!adjwday(t, type, val, 1, 1)) 437 return v; 438 } else { 439 val = trans(trans_mon, arg); 440 if (val != -1) { 441 if (!adjmon(t, type, val, 1, 1)) 442 return v; 443 } else 444 return v; 445 } 446 } else { 447 val = atoi(arg); 448 which = arg[len-1]; 449 450 switch (which) { 451 case 'S': 452 if (!adjsec(t, type, val, 1)) 453 return v; 454 break; 455 case 'M': 456 if (!adjmin(t, type, val, 1)) 457 return v; 458 break; 459 case 'H': 460 if (!adjhour(t, type, val, 1)) 461 return v; 462 break; 463 case 'd': 464 t->tm_isdst = -1; 465 if (!adjday(t, type, val, 1)) 466 return v; 467 break; 468 case 'w': 469 t->tm_isdst = -1; 470 if (!adjwday(t, type, val, 0, 1)) 471 return v; 472 break; 473 case 'm': 474 t->tm_isdst = -1; 475 if (!adjmon(t, type, val, 0, 1)) 476 return v; 477 break; 478 case 'y': 479 t->tm_isdst = -1; 480 if (!adjyear(t, type, val, 1)) 481 return v; 482 break; 483 default: 484 return v; 485 } 486 } 487 } 488 return 0; 489 } 490 491 void 492 vary_destroy(struct vary *v) 493 { 494 struct vary *n; 495 496 while (v) { 497 n = v->next; 498 free(v); 499 v = n; 500 } 501 } 502