diplodocus.org Git - nmh/blob - uip/picksbr.c

   1
   2 /*
   3  * picksbr.c -- routines to help pick along...
   4  *
   5  * $Id$
   6  */
   7
   8 #include <h/mh.h>
   9 #include <zotnet/tws/tws.h>
  10 #include <h/picksbr.h>
  11
  12 #ifdef TIME_WITH_SYS_TIME
  13 # include <sys/time.h>
  14 # include <time.h>
  15 #else
  16 # ifdef TM_IN_SYS_TIME
  17 #  include <sys/time.h>
  18 # else
  19 #  include <time.h>
  20 # endif
  21 #endif
  22
  23 static struct swit parswit[] = {
  24 #define PRAND                   0
  25     { "and", 0 },
  26 #define PROR                    1
  27     { "or", 0 },
  28 #define PRNOT                   2
  29     { "not", 0 },
  30 #define PRLBR                   3
  31     { "lbrace", 0 },
  32 #define PRRBR                   4
  33     { "rbrace", 0 },
  34 #define PRCC                    5
  35     { "cc  pattern", 0 },
  36 #define PRDATE                  6
  37     { "date  pattern", 0 },
  38 #define PRFROM                  7
  39     { "from  pattern", 0 },
  40 #define PRSRCH                  8
  41     { "search  pattern", 0 },
  42 #define PRSUBJ                  9
  43     { "subject  pattern", 0 },
  44 #define PRTO                   10
  45     { "to  pattern", 0 },
  46 #define PROTHR                 11
  47     { "-othercomponent  pattern", 15 },
  48 #define PRAFTR                 12
  49     { "after date", 0 },
  50 #define PRBEFR                 13
  51     { "before date", 0 },
  52 #define PRDATF                 14
  53     { "datefield field", 5 },
  54     { NULL, 0 }
  55 };
  56
  57 /* DEFINITIONS FOR PATTERN MATCHING */
  58
  59 /*
  60  * We really should be using re_comp() and re_exec() here.  Unfortunately,
  61  * pick advertises that lowercase characters matches characters of both
  62  * cases.  Since re_exec() doesn't exhibit this behavior, we are stuck
  63  * with this version.  Furthermore, we need to be able to save and restore
  64  * the state of the pattern matcher in order to do things "efficiently".
  65  *
  66  * The matching power of this algorithm isn't as powerful as the re_xxx()
  67  * routines (no \(xxx\) and \n constructs).  Such is life.
  68  */
  69
  70 #define CCHR    2
  71 #define CDOT    4
  72 #define CCL     6
  73 #define NCCL    8
  74 #define CDOL    10
  75 #define CEOF    11
  76
  77 #define STAR    01
  78
  79 #define LBSIZE  1024
  80 #define ESIZE   256
  81
  82
  83 static char linebuf[LBSIZE + 1];
  84
  85 /* the magic array for case-independence */
  86 static char cc[] = {
  87         0000,0001,0002,0003,0004,0005,0006,0007,
  88         0010,0011,0012,0013,0014,0015,0016,0017,
  89         0020,0021,0022,0023,0024,0025,0026,0027,
  90         0030,0031,0032,0033,0034,0035,0036,0037,
  91         0040,0041,0042,0043,0044,0045,0046,0047,
  92         0050,0051,0052,0053,0054,0055,0056,0057,
  93         0060,0061,0062,0063,0064,0065,0066,0067,
  94         0070,0071,0072,0073,0074,0075,0076,0077,
  95         0100,0141,0142,0143,0144,0145,0146,0147,
  96         0150,0151,0152,0153,0154,0155,0156,0157,
  97         0160,0161,0162,0163,0164,0165,0166,0167,
  98         0170,0171,0172,0133,0134,0135,0136,0137,
  99         0140,0141,0142,0143,0144,0145,0146,0147,
 100         0150,0151,0152,0153,0154,0155,0156,0157,
 101         0160,0161,0162,0163,0164,0165,0166,0167,
 102         0170,0171,0172,0173,0174,0175,0176,0177,
 103 };
 104
 105 /*
 106  * DEFINITIONS FOR NEXUS
 107  */
 108
 109 #define nxtarg()        (*argp ? *argp++ : NULL)
 110 #define prvarg()        argp--
 111
 112 #define padvise         if (!talked++) advise
 113
 114 struct nexus {
 115     int (*n_action)();
 116
 117     union {
 118         /* for {OR,AND,NOT}action */
 119         struct {
 120             struct nexus *un_L_child;
 121             struct nexus *un_R_child;
 122         } st1;
 123
 124         /* for GREPaction */
 125         struct {
 126             int   un_header;
 127             int   un_circf;
 128             char  un_expbuf[ESIZE];
 129             char *un_patbuf;
 130         } st2;
 131
 132         /* for TWSaction */
 133         struct {
 134             char *un_datef;
 135             int   un_after;
 136             struct tws un_tws;
 137         } st3;
 138     } un;
 139 };
 140
 141 #define n_L_child un.st1.un_L_child
 142 #define n_R_child un.st1.un_R_child
 143
 144 #define n_header un.st2.un_header
 145 #define n_circf  un.st2.un_circf
 146 #define n_expbuf un.st2.un_expbuf
 147 #define n_patbuf un.st2.un_patbuf
 148
 149 #define n_datef  un.st3.un_datef
 150 #define n_after  un.st3.un_after
 151 #define n_tws    un.st3.un_tws
 152
 153 static int talked;
 154 static int pdebug = 0;
 155
 156 static char *datesw;
 157 static char **argp;
 158
 159 static struct nexus *head;
 160
 161 /*
 162  * prototypes for date routines
 163  */
 164 static struct tws *tws_parse();
 165 static struct tws *tws_special();
 166
 167 /*
 168  * static prototypes
 169  */
 170 static void PRaction();
 171 static int gcompile();
 172 static int advance();
 173 static int cclass();
 174 static int tcompile();
 175
 176 static struct nexus *parse();
 177 static struct nexus *exp1();
 178 static struct nexus *exp2();
 179 static struct nexus *exp3();
 180 static struct nexus *newnexus();
 181
 182 static int ORaction();
 183 static int ANDaction();
 184 static int NOTaction();
 185 static int GREPaction();
 186 static int TWSaction();
 187
 188
 189 int
 190 pcompile (char **vec, char *date)
 191 {
 192     register char *cp;
 193
 194     if ((cp = getenv ("MHPDEBUG")) && *cp)
 195         pdebug++;
 196
 197     argp = vec;
 198     if ((datesw = date) == NULL)
 199         datesw = "date";
 200     talked = 0;
 201
 202     if ((head = parse ()) == NULL)
 203         return (talked ? 0 : 1);
 204
 205     if (*argp) {
 206         padvise (NULL, "%s unexpected", *argp);
 207         return 0;
 208     }
 209
 210     return 1;
 211 }
 212
 213
 214 static struct nexus *
 215 parse (void)
 216 {
 217     register char  *cp;
 218     register struct nexus *n, *o;
 219
 220     if ((n = exp1 ()) == NULL || (cp = nxtarg ()) == NULL)
 221         return n;
 222
 223     if (*cp != '-') {
 224         padvise (NULL, "%s unexpected", cp);
 225         return NULL;
 226     }
 227
 228     if (*++cp == '-')
 229         goto header;
 230     switch (smatch (cp, parswit)) {
 231         case AMBIGSW:
 232             ambigsw (cp, parswit);
 233             talked++;
 234             return NULL;
 235         case UNKWNSW:
 236             fprintf (stderr, "-%s unknown\n", cp);
 237             talked++;
 238             return NULL;
 239
 240         case PROR:
 241             o = newnexus (ORaction);
 242             o->n_L_child = n;
 243             if ((o->n_R_child = parse ()))
 244                 return o;
 245             padvise (NULL, "missing disjunctive");
 246             return NULL;
 247
 248 header: ;
 249         default:
 250             prvarg ();
 251             return n;
 252     }
 253 }
 254
 255 static struct nexus *
 256 exp1 (void)
 257 {
 258     register char *cp;
 259     register struct nexus *n, *o;
 260
 261     if ((n = exp2 ()) == NULL || (cp = nxtarg ()) == NULL)
 262         return n;
 263
 264     if (*cp != '-') {
 265         padvise (NULL, "%s unexpected", cp);
 266         return NULL;
 267     }
 268
 269     if (*++cp == '-')
 270         goto header;
 271     switch (smatch (cp, parswit)) {
 272         case AMBIGSW:
 273             ambigsw (cp, parswit);
 274             talked++;
 275             return NULL;
 276         case UNKWNSW:
 277             fprintf (stderr, "-%s unknown\n", cp);
 278             talked++;
 279             return NULL;
 280
 281         case PRAND:
 282             o = newnexus (ANDaction);
 283             o->n_L_child = n;
 284             if ((o->n_R_child = exp1 ()))
 285                 return o;
 286             padvise (NULL, "missing conjunctive");
 287             return NULL;
 288
 289 header: ;
 290         default:
 291             prvarg ();
 292             return n;
 293     }
 294 }
 295
 296
 297 static struct nexus *
 298 exp2 (void)
 299 {
 300     register char *cp;
 301     register struct nexus *n;
 302
 303     if ((cp = nxtarg ()) == NULL)
 304         return NULL;
 305
 306     if (*cp != '-') {
 307         prvarg ();
 308         return exp3 ();
 309     }
 310
 311     if (*++cp == '-')
 312         goto header;
 313     switch (smatch (cp, parswit)) {
 314         case AMBIGSW:
 315             ambigsw (cp, parswit);
 316             talked++;
 317             return NULL;
 318         case UNKWNSW:
 319             fprintf (stderr, "-%s unknown\n", cp);
 320             talked++;
 321             return NULL;
 322
 323         case PRNOT:
 324             n = newnexus (NOTaction);
 325             if ((n->n_L_child = exp3 ()))
 326                 return n;
 327             padvise (NULL, "missing negation");
 328             return NULL;
 329
 330 header: ;
 331         default:
 332             prvarg ();
 333             return exp3 ();
 334     }
 335 }
 336
 337 static struct nexus *
 338 exp3 (void)
 339 {
 340     int i;
 341     register char *cp, *dp;
 342     char buffer[BUFSIZ], temp[64];
 343     register struct nexus *n;
 344
 345     if ((cp = nxtarg ()) == NULL)
 346         return NULL;
 347
 348     if (*cp != '-') {
 349         padvise (NULL, "%s unexpected", cp);
 350         return NULL;
 351     }
 352
 353     if (*++cp == '-') {
 354         dp = ++cp;
 355         goto header;
 356     }
 357     switch (i = smatch (cp, parswit)) {
 358         case AMBIGSW:
 359             ambigsw (cp, parswit);
 360             talked++;
 361             return NULL;
 362         case UNKWNSW:
 363             fprintf (stderr, "-%s unknown\n", cp);
 364             talked++;
 365             return NULL;
 366
 367         case PRLBR:
 368             if ((n = parse ()) == NULL) {
 369                 padvise (NULL, "missing group");
 370                 return NULL;
 371             }
 372             if ((cp = nxtarg ()) == NULL) {
 373                 padvise (NULL, "missing -rbrace");
 374                 return NULL;
 375             }
 376             if (*cp++ == '-' && smatch (cp, parswit) == PRRBR)
 377                 return n;
 378             padvise (NULL, "%s unexpected", --cp);
 379             return NULL;
 380
 381         default:
 382             prvarg ();
 383             return NULL;
 384
 385         case PRCC:
 386         case PRDATE:
 387         case PRFROM:
 388         case PRTO:
 389         case PRSUBJ:
 390             strncpy(temp, parswit[i].sw, sizeof(temp));
 391             temp[sizeof(temp) - 1] = '\0';
 392             dp = *brkstring (temp, " ", NULL);
 393     header: ;
 394             if (!(cp = nxtarg ())) {/* allow -xyz arguments */
 395                 padvise (NULL, "missing argument to %s", argp[-2]);
 396                 return NULL;
 397             }
 398             n = newnexus (GREPaction);
 399             n->n_header = 1;
 400             snprintf (buffer, sizeof(buffer), "^%s[ \t]*:.*%s", dp, cp);
 401             dp = buffer;
 402             goto pattern;
 403
 404         case PRSRCH:
 405             n = newnexus (GREPaction);
 406             n->n_header = 0;
 407             if (!(cp = nxtarg ())) {/* allow -xyz arguments */
 408                 padvise (NULL, "missing argument to %s", argp[-2]);
 409                 return NULL;
 410             }
 411             dp = cp;
 412     pattern: ;
 413             if (!gcompile (n, dp)) {
 414                 padvise (NULL, "pattern error in %s %s", argp[-2], cp);
 415                 return NULL;
 416             }
 417             n->n_patbuf = getcpy (dp);
 418             return n;
 419
 420         case PROTHR:
 421             padvise (NULL, "internal error!");
 422             return NULL;
 423
 424         case PRDATF:
 425             if (!(datesw = nxtarg ()) || *datesw == '-') {
 426                 padvise (NULL, "missing argument to %s", argp[-2]);
 427                 return NULL;
 428             }
 429             return exp3 ();
 430
 431         case PRAFTR:
 432         case PRBEFR:
 433             if (!(cp = nxtarg ())) {/* allow -xyz arguments */
 434                 padvise (NULL, "missing argument to %s", argp[-2]);
 435                 return NULL;
 436             }
 437             n = newnexus (TWSaction);
 438             n->n_datef = datesw;
 439             if (!tcompile (cp, &n->n_tws, n->n_after = i == PRAFTR)) {
 440                 padvise (NULL, "unable to parse %s %s", argp[-2], cp);
 441                 return NULL;
 442             }
 443             return n;
 444     }
 445 }
 446
 447
 448 static struct nexus *
 449 newnexus (int (*action)())
 450 {
 451     register struct nexus *p;
 452
 453     if ((p = (struct nexus *) calloc ((size_t) 1, sizeof *p)) == NULL)
 454         adios (NULL, "unable to allocate component storage");
 455
 456     p->n_action = action;
 457     return p;
 458 }
 459
 460
 461 #define args(a) a, fp, msgnum, start, stop
 462 #define params  args (n)
 463 #define plist   \
 464             register struct nexus  *n; \
 465             register FILE *fp; \
 466             int msgnum; \
 467             long    start, \
 468                     stop;
 469
 470 int
 471 pmatches (FILE *fp, int msgnum, long start, long stop)
 472 {
 473     if (!head)
 474         return 1;
 475
 476     if (!talked++ && pdebug)
 477         PRaction (head, 0);
 478
 479     return (*head->n_action) (args (head));
 480 }
 481
 482
 483 static void
 484 PRaction (struct nexus *n, int level)
 485 {
 486     register int i;
 487
 488     for (i = 0; i < level; i++)
 489         fprintf (stderr, "| ");
 490
 491     if (n->n_action == ORaction) {
 492         fprintf (stderr, "OR\n");
 493         PRaction (n->n_L_child, level + 1);
 494         PRaction (n->n_R_child, level + 1);
 495         return;
 496     }
 497     if (n->n_action == ANDaction) {
 498         fprintf (stderr, "AND\n");
 499         PRaction (n->n_L_child, level + 1);
 500         PRaction (n->n_R_child, level + 1);
 501         return;
 502     }
 503     if (n->n_action == NOTaction) {
 504         fprintf (stderr, "NOT\n");
 505         PRaction (n->n_L_child, level + 1);
 506         return;
 507     }
 508     if (n->n_action == GREPaction) {
 509         fprintf (stderr, "PATTERN(%s) %s\n",
 510                 n->n_header ? "header" : "body", n->n_patbuf);
 511         return;
 512     }
 513     if (n->n_action == TWSaction) {
 514         fprintf (stderr, "TEMPORAL(%s) %s: %s\n",
 515                 n->n_after ? "after" : "before", n->n_datef,
 516                 dasctime (&n->n_tws, TW_NULL));
 517         return;
 518     }
 519     fprintf (stderr, "UNKNOWN(0x%x)\n", (unsigned int) (*n->n_action));
 520 }
 521
 522
 523 static int
 524 ORaction (params)
 525 plist
 526 {
 527     if ((*n->n_L_child->n_action) (args (n->n_L_child)))
 528         return 1;
 529     return (*n->n_R_child->n_action) (args (n->n_R_child));
 530 }
 531
 532
 533 static int
 534 ANDaction (params)
 535 plist
 536 {
 537     if (!(*n->n_L_child->n_action) (args (n->n_L_child)))
 538         return 0;
 539     return (*n->n_R_child->n_action) (args (n->n_R_child));
 540 }
 541
 542
 543 static int
 544 NOTaction (params)
 545 plist
 546 {
 547     return (!(*n->n_L_child->n_action) (args (n->n_L_child)));
 548 }
 549
 550
 551 static int
 552 gcompile (struct nexus *n, char *astr)
 553 {
 554     register int c;
 555     int cclcnt;
 556     register char *ep, *dp, *sp, *lastep;
 557
 558     dp = (ep = n->n_expbuf) + sizeof n->n_expbuf;
 559     sp = astr;
 560     if (*sp == '^') {
 561         n->n_circf = 1;
 562         sp++;
 563     }
 564     else
 565         n->n_circf = 0;
 566     for (;;) {
 567         if (ep >= dp)
 568             goto cerror;
 569         if ((c = *sp++) != '*')
 570             lastep = ep;
 571         switch (c) {
 572             case '\0':
 573                 *ep++ = CEOF;
 574                 return 1;
 575
 576             case '.':
 577                 *ep++ = CDOT;
 578                 continue;
 579
 580             case '*':
 581                 if (lastep == 0)
 582                     goto defchar;
 583                 *lastep |= STAR;
 584                 continue;
 585
 586             case '$':
 587                 if (*sp != '\0')
 588                     goto defchar;
 589                 *ep++ = CDOL;
 590                 continue;
 591
 592             case '[':
 593                 *ep++ = CCL;
 594                 *ep++ = 0;
 595                 cclcnt = 1;
 596                 if ((c = *sp++) == '^') {
 597                     c = *sp++;
 598                     ep[-2] = NCCL;
 599                 }
 600                 do {
 601                     *ep++ = c;
 602                     cclcnt++;
 603                     if (c == '\0' || ep >= dp)
 604                         goto cerror;
 605                 } while ((c = *sp++) != ']');
 606                 lastep[1] = cclcnt;
 607                 continue;
 608
 609             case '\\':
 610                 if ((c = *sp++) == '\0')
 611                     goto cerror;
 612         defchar:
 613             default:
 614                 *ep++ = CCHR;
 615                 *ep++ = c;
 616         }
 617     }
 618
 619 cerror: ;
 620     return 0;
 621 }
 622
 623
 624 static int
 625 GREPaction (params)
 626 plist
 627 {
 628     int c, body, lf;
 629     long pos = start;
 630     register char *p1, *p2, *ebp, *cbp;
 631     char ibuf[BUFSIZ];
 632
 633     fseek (fp, start, SEEK_SET);
 634     body = 0;
 635     ebp = cbp = ibuf;
 636     for (;;) {
 637         if (body && n->n_header)
 638             return 0;
 639         p1 = linebuf;
 640         p2 = cbp;
 641         lf = 0;
 642         for (;;) {
 643             if (p2 >= ebp) {
 644                 if (fgets (ibuf, sizeof ibuf, fp) == NULL
 645                         || (stop && pos >= stop)) {
 646                     if (lf)
 647                         break;
 648                     return 0;
 649                 }
 650                 pos += (long) strlen (ibuf);
 651                 p2 = ibuf;
 652                 ebp = ibuf + strlen (ibuf);
 653             }
 654             c = *p2++;
 655             if (lf && c != '\n') {
 656                 if (c != ' ' && c != '\t') {
 657                     --p2;
 658                     break;
 659                 }
 660                 else
 661                     lf = 0;
 662             }
 663             if (c == '\n') {
 664                 if (body)
 665                     break;
 666                 else {
 667                     if (lf) {
 668                         body++;
 669                         break;
 670                     }
 671                     lf++;
 672                     c = ' ';
 673                 }
 674             }
 675             if (c && p1 < &linebuf[LBSIZE - 1])
 676                 *p1++ = c;
 677         }
 678
 679         *p1++ = 0;
 680         cbp = p2;
 681         p1 = linebuf;
 682         p2 = n->n_expbuf;
 683
 684         if (n->n_circf) {
 685             if (advance (p1, p2))
 686                 return 1;
 687             continue;
 688         }
 689
 690         if (*p2 == CCHR) {
 691             c = p2[1];
 692             do {
 693                 if (*p1 == c || cc[(unsigned char)*p1] == c)
 694                     if (advance (p1, p2))
 695                         return 1;
 696             } while (*p1++);
 697             continue;
 698         }
 699
 700         do {
 701             if (advance (p1, p2))
 702                 return 1;
 703         } while (*p1++);
 704     }
 705 }
 706
 707
 708 static int
 709 advance (char *alp, char *aep)
 710 {
 711     register char *lp, *ep, *curlp;
 712
 713     lp = alp;
 714     ep = aep;
 715     for (;;)
 716         switch (*ep++) {
 717             case CCHR:
 718                 if (*ep++ == *lp++ || ep[-1] == cc[(unsigned char)lp[-1]])
 719                     continue;
 720                 return 0;
 721
 722             case CDOT:
 723                 if (*lp++)
 724                     continue;
 725                 return 0;
 726
 727             case CDOL:
 728                 if (*lp == 0)
 729                     continue;
 730                 return 0;
 731
 732             case CEOF:
 733                 return 1;
 734
 735             case CCL:
 736                 if (cclass (ep, *lp++, 1)) {
 737                     ep += *ep;
 738                     continue;
 739                 }
 740                 return 0;
 741
 742             case NCCL:
 743                 if (cclass (ep, *lp++, 0)) {
 744                     ep += *ep;
 745                     continue;
 746                 }
 747                 return 0;
 748
 749             case CDOT | STAR:
 750                 curlp = lp;
 751                 while (*lp++)
 752                     continue;
 753                 goto star;
 754
 755             case CCHR | STAR:
 756                 curlp = lp;
 757                 while (*lp++ == *ep || cc[(unsigned char)lp[-1]] == *ep)
 758                     continue;
 759                 ep++;
 760                 goto star;
 761
 762             case CCL | STAR:
 763             case NCCL | STAR:
 764                 curlp = lp;
 765                 while (cclass (ep, *lp++, ep[-1] == (CCL | STAR)))
 766                     continue;
 767                 ep += *ep;
 768                 goto star;
 769
 770         star:
 771                 do {
 772                     lp--;
 773                     if (advance (lp, ep))
 774                         return (1);
 775                 } while (lp > curlp);
 776                 return 0;
 777
 778             default:
 779                 admonish (NULL, "advance() botch -- you lose big");
 780                 return 0;
 781         }
 782 }
 783
 784
 785 static int
 786 cclass (char *aset, int ac, int af)
 787 {
 788     register int    n;
 789     register char   c,
 790                    *set;
 791
 792     set = aset;
 793     if ((c = ac) == 0)
 794         return (0);
 795
 796     n = *set++;
 797     while (--n)
 798         if (*set++ == c)
 799             return (af);
 800
 801     return (!af);
 802 }
 803
 804
 805 static int
 806 tcompile (char *ap, struct tws *tb, int isafter)
 807 {
 808     register struct tws *tw;
 809
 810     if ((tw = tws_parse (ap, isafter)) == NULL)
 811         return 0;
 812
 813     twscopy (tb, tw);
 814     return 1;
 815 }
 816
 817
 818 static struct tws *
 819 tws_parse (char *ap, int isafter)
 820 {
 821     char buffer[BUFSIZ];
 822     register struct tws *tw, *ts;
 823
 824     if ((tw = tws_special (ap)) != NULL) {
 825         tw->tw_sec = tw->tw_min = isafter ? 59 : 0;
 826         tw->tw_hour = isafter ? 23 : 0;
 827         return tw;
 828     }
 829     if ((tw = dparsetime (ap)) != NULL)
 830         return tw;
 831
 832     if ((ts = dlocaltimenow ()) == NULL)
 833         return NULL;
 834
 835     snprintf (buffer, sizeof(buffer), "%s %s", ap, dtwszone (ts));
 836     if ((tw = dparsetime (buffer)) != NULL)
 837         return tw;
 838
 839     snprintf (buffer, sizeof(buffer), "%s %02d:%02d:%02d %s", ap,
 840             ts->tw_hour, ts->tw_min, ts->tw_sec, dtwszone (ts));
 841     if ((tw = dparsetime (buffer)) != NULL)
 842         return tw;
 843
 844     snprintf (buffer, sizeof(buffer), "%02d %s %04d %s",
 845             ts->tw_mday, tw_moty[ts->tw_mon], ts->tw_year, ap);
 846     if ((tw = dparsetime (buffer)) != NULL)
 847         return tw;
 848
 849     snprintf (buffer, sizeof(buffer), "%02d %s %04d %s %s",
 850             ts->tw_mday, tw_moty[ts->tw_mon], ts->tw_year,
 851             ap, dtwszone (ts));
 852     if ((tw = dparsetime (buffer)) != NULL)
 853         return tw;
 854
 855     return NULL;
 856 }
 857
 858
 859 static struct tws *
 860 tws_special (char *ap)
 861 {
 862     int i;
 863     time_t clock;
 864     register struct tws *tw;
 865
 866     time (&clock);
 867     if (!strcasecmp (ap, "today"))
 868         return dlocaltime (&clock);
 869     if (!strcasecmp (ap, "yesterday")) {
 870         clock -= (long) (60 * 60 * 24);
 871         return dlocaltime (&clock);
 872     }
 873     if (!strcasecmp (ap, "tomorrow")) {
 874         clock += (long) (60 * 60 * 24);
 875         return dlocaltime (&clock);
 876     }
 877
 878     for (i = 0; tw_ldotw[i]; i++)
 879         if (!strcasecmp (ap, tw_ldotw[i]))
 880             break;
 881     if (tw_ldotw[i]) {
 882         if ((tw = dlocaltime (&clock)) == NULL)
 883             return NULL;
 884         if ((i -= tw->tw_wday) > 0)
 885             i -= 7;
 886     }
 887     else
 888         if (*ap != '-')
 889             return NULL;
 890         else                    /* -ddd days ago */
 891             i = atoi (ap);      /* we should error check this */
 892
 893     clock += (long) ((60 * 60 * 24) * i);
 894     return dlocaltime (&clock);
 895 }
 896
 897
 898 static int
 899 TWSaction (params)
 900 plist
 901 {
 902     int state;
 903     register char *bp;
 904     char buf[BUFSIZ], name[NAMESZ];
 905     register struct tws *tw;
 906
 907     fseek (fp, start, SEEK_SET);
 908     for (state = FLD, bp = NULL;;) {
 909         switch (state = m_getfld (state, name, buf, sizeof buf, fp)) {
 910             case FLD:
 911             case FLDEOF:
 912             case FLDPLUS:
 913                 if (bp != NULL)
 914                     free (bp), bp = NULL;
 915                 bp = add (buf, NULL);
 916                 while (state == FLDPLUS) {
 917                     state = m_getfld (state, name, buf, sizeof buf, fp);
 918                     bp = add (buf, bp);
 919                 }
 920                 if (!strcasecmp (name, n->n_datef))
 921                     break;
 922                 if (state != FLDEOF)
 923                     continue;
 924
 925             case BODY:
 926             case BODYEOF:
 927             case FILEEOF:
 928             case LENERR:
 929             case FMTERR:
 930                 if (state == LENERR || state == FMTERR)
 931                     advise (NULL, "format error in message %d", msgnum);
 932                 if (bp != NULL)
 933                     free (bp);
 934                 return 0;
 935
 936             default:
 937                 adios (NULL, "internal error -- you lose");
 938         }
 939         break;
 940     }
 941
 942     if ((tw = dparsetime (bp)) == NULL)
 943         advise (NULL, "unable to parse %s field in message %d, matching...",
 944                 n->n_datef, msgnum), state = 1;
 945     else
 946         state = n->n_after ? (twsort (tw, &n->n_tws) > 0)
 947             : (twsort (tw, &n->n_tws) < 0);
 948
 949     if (bp != NULL)
 950         free (bp);
 951     return state;
 952 }