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 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <err.h> 31 #include <time.h> 32 #include <stdint.h> 33 #include <string.h> 34 #include <stdlib.h> 35 #include "vary.h" 36 37 struct trans { 38 int64_t val; 39 const char *str; 40 }; 41 42 static struct trans trans_mon[] = { 43 { 1, "january" }, { 2, "february" }, { 3, "march" }, { 4, "april" }, 44 { 5, "may"}, { 6, "june" }, { 7, "july" }, { 8, "august" }, 45 { 9, "september" }, { 10, "october" }, { 11, "november" }, { 12, "december" }, 46 { -1, NULL } 47 }; 48 49 static struct trans trans_wday[] = { 50 { 0, "sunday" }, { 1, "monday" }, { 2, "tuesday" }, { 3, "wednesday" }, 51 { 4, "thursday" }, { 5, "friday" }, { 6, "saturday" }, 52 { -1, NULL } 53 }; 54 55 static char digits[] = "0123456789"; 56 static int adjhour(struct tm *, char, int64_t, int); 57 58 static int 59 domktime(struct tm *t, char type) 60 { 61 time_t ret; 62 63 while ((ret = mktime(t)) == -1 && t->tm_year > 68 && t->tm_year < 138) 64 /* While mktime() fails, adjust by an hour */ 65 adjhour(t, type == '-' ? type : '+', 1, 0); 66 67 return ret; 68 } 69 70 static int 71 trans(const struct trans t[], const char *arg) 72 { 73 int f; 74 75 for (f = 0; t[f].val != -1; f++) 76 if (!strncasecmp(t[f].str, arg, 3) || 77 !strncasecmp(t[f].str, arg, strlen(t[f].str))) 78 return t[f].val; 79 80 return -1; 81 } 82 83 struct vary * 84 vary_append(struct vary *v, char *arg) 85 { 86 struct vary *result, **nextp; 87 88 if (v) { 89 result = v; 90 while (v->next) 91 v = v->next; 92 nextp = &v->next; 93 } else 94 nextp = &result; 95 96 if ((*nextp = (struct vary *)malloc(sizeof(struct vary))) == NULL) 97 err(1, "malloc"); 98 (*nextp)->arg = arg; 99 (*nextp)->next = NULL; 100 return result; 101 } 102 103 static int mdays[12] = { 31, 0, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }; 104 105 static int 106 daysinmonth(const struct tm *t) 107 { 108 int year; 109 110 year = t->tm_year + 1900; 111 112 if (t->tm_mon == 1) 113 if (!(year % 400)) 114 return 29; 115 else if (!(year % 100)) 116 return 28; 117 else if (!(year % 4)) 118 return 29; 119 else 120 return 28; 121 else if (t->tm_mon >= 0 && t->tm_mon < 12) 122 return mdays[t->tm_mon]; 123 124 return 0; 125 } 126 127 128 static int 129 adjyear(struct tm *t, char type, int64_t val, int mk) 130 { 131 switch (type) { 132 case '+': 133 t->tm_year += val; 134 break; 135 case '-': 136 t->tm_year -= val; 137 break; 138 default: 139 t->tm_year = val; 140 if (t->tm_year < 69) 141 t->tm_year += 100; /* as per date.c */ 142 else if (t->tm_year > 1900) 143 t->tm_year -= 1900; /* struct tm holds years since 1900 */ 144 break; 145 } 146 return !mk || domktime(t, type) != -1; 147 } 148 149 static int 150 adjmon(struct tm *t, char type, int64_t val, int istext, int mk) 151 { 152 int lmdays; 153 154 if (val < 0) 155 return 0; 156 157 switch (type) { 158 case '+': 159 if (istext) { 160 if (val <= t->tm_mon) 161 val += 11 - t->tm_mon; /* early next year */ 162 else 163 val -= t->tm_mon + 1; /* later this year */ 164 } 165 if (val) { 166 if (!adjyear(t, '+', (t->tm_mon + val) / 12, 0)) 167 return 0; 168 val %= 12; 169 t->tm_mon += val; 170 if (t->tm_mon > 11) 171 t->tm_mon -= 12; 172 } 173 break; 174 175 case '-': 176 if (istext) { 177 if (val-1 > t->tm_mon) 178 val = 13 - val + t->tm_mon; /* later last year */ 179 else 180 val = t->tm_mon - val + 1; /* early this year */ 181 } 182 if (val) { 183 if (!adjyear(t, '-', val / 12, 0)) 184 return 0; 185 val %= 12; 186 if (val > t->tm_mon) { 187 if (!adjyear(t, '-', 1, 0)) 188 return 0; 189 val -= 12; 190 } 191 t->tm_mon -= val; 192 } 193 break; 194 195 default: 196 if (val > 12 || val < 1) 197 return 0; 198 t->tm_mon = --val; 199 } 200 201 /* e.g., -v-1m on March, 31 is the last day of February in common sense */ 202 lmdays = daysinmonth(t); 203 if (t->tm_mday > lmdays) 204 t->tm_mday = lmdays; 205 206 return !mk || domktime(t, type) != -1; 207 } 208 209 static int 210 adjday(struct tm *t, char type, int64_t val, int mk) 211 { 212 int lmdays; 213 214 switch (type) { 215 case '+': 216 while (val) { 217 lmdays = daysinmonth(t); 218 if (val > lmdays - t->tm_mday) { 219 val -= lmdays - t->tm_mday + 1; 220 t->tm_mday = 1; 221 if (!adjmon(t, '+', 1, 0, 0)) 222 return 0; 223 } else { 224 t->tm_mday += val; 225 val = 0; 226 } 227 } 228 break; 229 case '-': 230 while (val) 231 if (val >= t->tm_mday) { 232 val -= t->tm_mday; 233 t->tm_mday = 1; 234 if (!adjmon(t, '-', 1, 0, 0)) 235 return 0; 236 t->tm_mday = daysinmonth(t); 237 } else { 238 t->tm_mday -= val; 239 val = 0; 240 } 241 break; 242 default: 243 if (val > 0 && val <= daysinmonth(t)) 244 t->tm_mday = val; 245 else 246 return 0; 247 break; 248 } 249 250 return !mk || domktime(t, type) != -1; 251 } 252 253 static int 254 adjwday(struct tm *t, char type, int64_t val, int istext, int mk) 255 { 256 if (val < 0) 257 return 0; 258 259 switch (type) { 260 case '+': 261 if (istext) 262 if (val < t->tm_wday) 263 val = 7 - t->tm_wday + val; /* early next week */ 264 else 265 val -= t->tm_wday; /* later this week */ 266 else 267 val *= 7; /* "-v+5w" == "5 weeks in the future" */ 268 return !val || adjday(t, '+', val, mk); 269 case '-': 270 if (istext) { 271 if (val > t->tm_wday) 272 val = 7 - val + t->tm_wday; /* later last week */ 273 else 274 val = t->tm_wday - val; /* early this week */ 275 } else 276 val *= 7; /* "-v-5w" == "5 weeks ago" */ 277 return !val || adjday(t, '-', val, mk); 278 default: 279 if (val < t->tm_wday) 280 return adjday(t, '-', t->tm_wday - val, mk); 281 else if (val > 6) 282 return 0; 283 else if (val > t->tm_wday) 284 return adjday(t, '+', val - t->tm_wday, mk); 285 } 286 return 1; 287 } 288 289 static int 290 adjhour(struct tm *t, char type, int64_t val, int mk) 291 { 292 if (val < 0) 293 return 0; 294 295 switch (type) { 296 case '+': 297 if (val) { 298 int days; 299 300 days = (t->tm_hour + val) / 24; 301 val %= 24; 302 t->tm_hour += val; 303 t->tm_hour %= 24; 304 if (!adjday(t, '+', days, 0)) 305 return 0; 306 } 307 break; 308 309 case '-': 310 if (val) { 311 int days; 312 313 days = val / 24; 314 val %= 24; 315 if (val > t->tm_hour) { 316 days++; 317 val -= 24; 318 } 319 t->tm_hour -= val; 320 if (!adjday(t, '-', days, 0)) 321 return 0; 322 } 323 break; 324 325 default: 326 if (val > 23) 327 return 0; 328 t->tm_hour = val; 329 } 330 331 return !mk || domktime(t, type) != -1; 332 } 333 334 static int 335 adjmin(struct tm *t, char type, int64_t val, int mk) 336 { 337 if (val < 0) 338 return 0; 339 340 switch (type) { 341 case '+': 342 if (val) { 343 if (!adjhour(t, '+', (t->tm_min + val) / 60, 0)) 344 return 0; 345 val %= 60; 346 t->tm_min += val; 347 if (t->tm_min > 59) 348 t->tm_min -= 60; 349 } 350 break; 351 352 case '-': 353 if (val) { 354 if (!adjhour(t, '-', val / 60, 0)) 355 return 0; 356 val %= 60; 357 if (val > t->tm_min) { 358 if (!adjhour(t, '-', 1, 0)) 359 return 0; 360 val -= 60; 361 } 362 t->tm_min -= val; 363 } 364 break; 365 366 default: 367 if (val > 59) 368 return 0; 369 t->tm_min = val; 370 } 371 372 return !mk || domktime(t, type) != -1; 373 } 374 375 static int 376 adjsec(struct tm *t, char type, int64_t val, int mk) 377 { 378 if (val < 0) 379 return 0; 380 381 switch (type) { 382 case '+': 383 if (val) { 384 if (!adjmin(t, '+', (t->tm_sec + val) / 60, 0)) 385 return 0; 386 val %= 60; 387 t->tm_sec += val; 388 if (t->tm_sec > 59) 389 t->tm_sec -= 60; 390 } 391 break; 392 393 case '-': 394 if (val) { 395 if (!adjmin(t, '-', val / 60, 0)) 396 return 0; 397 val %= 60; 398 if (val > t->tm_sec) { 399 if (!adjmin(t, '-', 1, 0)) 400 return 0; 401 val -= 60; 402 } 403 t->tm_sec -= val; 404 } 405 break; 406 407 default: 408 if (val > 59) 409 return 0; 410 t->tm_sec = val; 411 } 412 413 return !mk || domktime(t, type) != -1; 414 } 415 416 const struct vary * 417 vary_apply(const struct vary *v, struct tm *t) 418 { 419 char type; 420 char which; 421 char *arg; 422 size_t len; 423 int64_t val; 424 425 for (; v; v = v->next) { 426 type = *v->arg; 427 arg = v->arg; 428 if (type == '+' || type == '-') 429 arg++; 430 else 431 type = '\0'; 432 len = strlen(arg); 433 if (len < 2) 434 return v; 435 436 if (type == '\0') 437 t->tm_isdst = -1; 438 439 if (strspn(arg, digits) != len-1) { 440 val = trans(trans_wday, arg); 441 if (val != -1) { 442 if (!adjwday(t, type, val, 1, 1)) 443 return v; 444 } else { 445 val = trans(trans_mon, arg); 446 if (val != -1) { 447 if (!adjmon(t, type, val, 1, 1)) 448 return v; 449 } else 450 return v; 451 } 452 } else { 453 val = atoi(arg); 454 which = arg[len-1]; 455 456 switch (which) { 457 case 'S': 458 if (!adjsec(t, type, val, 1)) 459 return v; 460 break; 461 case 'M': 462 if (!adjmin(t, type, val, 1)) 463 return v; 464 break; 465 case 'H': 466 if (!adjhour(t, type, val, 1)) 467 return v; 468 break; 469 case 'd': 470 t->tm_isdst = -1; 471 if (!adjday(t, type, val, 1)) 472 return v; 473 break; 474 case 'w': 475 t->tm_isdst = -1; 476 if (!adjwday(t, type, val, 0, 1)) 477 return v; 478 break; 479 case 'm': 480 t->tm_isdst = -1; 481 if (!adjmon(t, type, val, 0, 1)) 482 return v; 483 break; 484 case 'y': 485 t->tm_isdst = -1; 486 if (!adjyear(t, type, val, 1)) 487 return v; 488 break; 489 default: 490 return v; 491 } 492 } 493 } 494 return 0; 495 } 496 497 void 498 vary_destroy(struct vary *v) 499 { 500 struct vary *n; 501 502 while (v) { 503 n = v->next; 504 free(v); 505 v = n; 506 } 507 } 508