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

   1
   2 /*
   3  * picksbr.c -- routines to help pick along...
   4  *
   5  * This code is Copyright (c) 2002, by the authors of nmh.  See the
   6  * COPYRIGHT file in the root directory of the nmh distribution for
   7  * complete copyright information.
   8  */
   9
  10 #include <h/mh.h>
  11 #include <h/tws.h>
  12 #include <h/picksbr.h>
  13 #include <h/utils.h>
  14
  15 #ifdef HAVE_SYS_TIME_H
  16 # include <sys/time.h>
  17 #endif
  18 #include <time.h>
  19
  20 #define PARSE_SWITCHES \
  21     X("and", 0, PRAND) \
  22     X("or", 0, PROR) \
  23     X("not", 0, PRNOT) \
  24     X("lbrace", 0, PRLBR) \
  25     X("rbrace", 0, PRRBR) \
  26     X("cc  pattern", 0, PRCC) \
  27     X("date  pattern", 0, PRDATE) \
  28     X("from  pattern", 0, PRFROM) \
  29     X("search  pattern", 0, PRSRCH) \
  30     X("subject  pattern", 0, PRSUBJ) \
  31     X("to  pattern", 0, PRTO) \
  32     X("-othercomponent  pattern", 15, PROTHR) \
  33     X("after date", 0, PRAFTR) \
  34     X("before date", 0, PRBEFR) \
  35     X("datefield field", 5, PRDATF) \
  36
  37 #define X(sw, minchars, id) id,
  38 DEFINE_SWITCH_ENUM(PARSE);
  39 #undef X
  40
  41 #define X(sw, minchars, id) { sw, minchars, id },
  42 DEFINE_SWITCH_ARRAY(PARSE, parswit);
  43 #undef X
  44
  45 /* DEFINITIONS FOR PATTERN MATCHING */
  46
  47 /*
  48  * We really should be using re_comp() and re_exec() here.  Unfortunately,
  49  * pick advertises that lowercase characters matches characters of both
  50  * cases.  Since re_exec() doesn't exhibit this behavior, we are stuck
  51  * with this version.  Furthermore, we need to be able to save and restore
  52  * the state of the pattern matcher in order to do things "efficiently".
  53  *
  54  * The matching power of this algorithm isn't as powerful as the re_xxx()
  55  * routines (no \(xxx\) and \n constructs).  Such is life.
  56  */
  57
  58 #define CCHR    2
  59 #define CDOT    4
  60 #define CCL     6
  61 #define NCCL    8
  62 #define CDOL    10
  63 #define CEOF    11
  64
  65 #define STAR    01
  66
  67 #define LBSIZE  1024
  68 #define ESIZE   1024
  69
  70
  71 static char linebuf[LBSIZE + 1];
  72 static char decoded_linebuf[LBSIZE + 1];
  73
  74 /* the magic array for case-independence */
  75 static unsigned char cc[] = {
  76         0000,0001,0002,0003,0004,0005,0006,0007,
  77         0010,0011,0012,0013,0014,0015,0016,0017,
  78         0020,0021,0022,0023,0024,0025,0026,0027,
  79         0030,0031,0032,0033,0034,0035,0036,0037,
  80         0040,0041,0042,0043,0044,0045,0046,0047,
  81         0050,0051,0052,0053,0054,0055,0056,0057,
  82         0060,0061,0062,0063,0064,0065,0066,0067,
  83         0070,0071,0072,0073,0074,0075,0076,0077,
  84         0100,0141,0142,0143,0144,0145,0146,0147,
  85         0150,0151,0152,0153,0154,0155,0156,0157,
  86         0160,0161,0162,0163,0164,0165,0166,0167,
  87         0170,0171,0172,0133,0134,0135,0136,0137,
  88         0140,0141,0142,0143,0144,0145,0146,0147,
  89         0150,0151,0152,0153,0154,0155,0156,0157,
  90         0160,0161,0162,0163,0164,0165,0166,0167,
  91         0170,0171,0172,0173,0174,0175,0176,0177,
  92
  93         0200,0201,0202,0203,0204,0205,0206,0207,
  94         0210,0211,0212,0213,0214,0215,0216,0217,
  95         0220,0221,0222,0223,0224,0225,0226,0227,
  96         0230,0231,0232,0233,0234,0235,0236,0237,
  97         0240,0241,0242,0243,0244,0245,0246,0247,
  98         0250,0251,0252,0253,0254,0255,0256,0257,
  99         0260,0261,0262,0263,0264,0265,0266,0267,
 100         0270,0271,0272,0273,0274,0275,0276,0277,
 101         0300,0301,0302,0303,0304,0305,0306,0307,
 102         0310,0311,0312,0313,0314,0315,0316,0317,
 103         0320,0321,0322,0323,0324,0325,0326,0327,
 104         0330,0331,0332,0333,0334,0335,0336,0337,
 105         0340,0341,0342,0343,0344,0345,0346,0347,
 106         0350,0351,0352,0353,0354,0355,0356,0357,
 107         0360,0361,0362,0363,0364,0365,0366,0367,
 108         0370,0371,0372,0373,0374,0375,0376,0377,
 109 };
 110
 111 /*
 112  * DEFINITIONS FOR NEXUS
 113  */
 114
 115 #define nxtarg()        (*argp ? *argp++ : NULL)
 116 #define prvarg()        argp--
 117
 118 #define padvise         if (!talked++) advise
 119
 120 struct nexus {
 121     int (*n_action)();
 122
 123     union {
 124         /* for {OR,AND,NOT}action */
 125         struct {
 126             struct nexus *un_L_child;
 127             struct nexus *un_R_child;
 128         } st1;
 129
 130         /* for GREPaction */
 131         struct {
 132             int   un_header;
 133             int   un_circf;
 134             char  un_expbuf[ESIZE];
 135             char *un_patbuf;
 136         } st2;
 137
 138         /* for TWSaction */
 139         struct {
 140             char *un_datef;
 141             int   un_after;
 142             struct tws un_tws;
 143         } st3;
 144     } un;
 145 };
 146
 147 #define n_L_child un.st1.un_L_child
 148 #define n_R_child un.st1.un_R_child
 149
 150 #define n_header un.st2.un_header
 151 #define n_circf  un.st2.un_circf
 152 #define n_expbuf un.st2.un_expbuf
 153 #define n_patbuf un.st2.un_patbuf
 154
 155 #define n_datef  un.st3.un_datef
 156 #define n_after  un.st3.un_after
 157 #define n_tws    un.st3.un_tws
 158
 159 static int talked;
 160 static int pdebug = 0;
 161
 162 static char *datesw;
 163 static char **argp;
 164
 165 static struct nexus *head;
 166
 167 /*
 168  * prototypes for date routines
 169  */
 170 static struct tws *tws_parse(char *, int);
 171 static struct tws *tws_special(char *);
 172
 173 /*
 174  * static prototypes
 175  */
 176 static void PRaction(struct nexus *, int);
 177 static int gcompile(struct nexus *, char *);
 178 static int advance(char *, char *);
 179 static int cclass(unsigned char *, int, int);
 180 static int tcompile(char *, struct tws *, int);
 181
 182 static struct nexus *parse(void);
 183 static struct nexus *nexp1(void);
 184 static struct nexus *nexp2(void);
 185 static struct nexus *nexp3(void);
 186 static struct nexus *newnexus(int (*)());
 187
 188 static int ORaction();
 189 static int ANDaction();
 190 static int NOTaction();
 191 static int GREPaction();
 192 static int TWSaction();
 193
 194
 195 int
 196 pcompile (char **vec, char *date)
 197 {
 198     register char *cp;
 199
 200     if ((cp = getenv ("MHPDEBUG")) && *cp)
 201         pdebug++;
 202
 203     argp = vec;
 204     if ((datesw = date) == NULL)
 205         datesw = "date";
 206     talked = 0;
 207
 208     if ((head = parse ()) == NULL)
 209         return (talked ? 0 : 1);
 210
 211     if (*argp) {
 212         padvise (NULL, "%s unexpected", *argp);
 213         return 0;
 214     }
 215
 216     return 1;
 217 }
 218
 219
 220 static struct nexus *
 221 parse (void)
 222 {
 223     register char  *cp;
 224     register struct nexus *n, *o;
 225
 226     if ((n = nexp1 ()) == NULL || (cp = nxtarg ()) == NULL)
 227         return n;
 228
 229     if (*cp != '-') {
 230         padvise (NULL, "%s unexpected", cp);
 231         return NULL;
 232     }
 233
 234     if (*++cp == '-')
 235         goto header;
 236     switch (smatch (cp, parswit)) {
 237         case AMBIGSW:
 238             ambigsw (cp, parswit);
 239             talked++;
 240             return NULL;
 241         case UNKWNSW:
 242             fprintf (stderr, "-%s unknown\n", cp);
 243             talked++;
 244             return NULL;
 245
 246         case PROR:
 247             o = newnexus (ORaction);
 248             o->n_L_child = n;
 249             if ((o->n_R_child = parse ()))
 250                 return o;
 251             padvise (NULL, "missing disjunctive");
 252             return NULL;
 253
 254 header: ;
 255         default:
 256             prvarg ();
 257             return n;
 258     }
 259 }
 260
 261 static struct nexus *
 262 nexp1 (void)
 263 {
 264     register char *cp;
 265     register struct nexus *n, *o;
 266
 267     if ((n = nexp2 ()) == NULL || (cp = nxtarg ()) == NULL)
 268         return n;
 269
 270     if (*cp != '-') {
 271         padvise (NULL, "%s unexpected", cp);
 272         return NULL;
 273     }
 274
 275     if (*++cp == '-')
 276         goto header;
 277     switch (smatch (cp, parswit)) {
 278         case AMBIGSW:
 279             ambigsw (cp, parswit);
 280             talked++;
 281             return NULL;
 282         case UNKWNSW:
 283             fprintf (stderr, "-%s unknown\n", cp);
 284             talked++;
 285             return NULL;
 286
 287         case PRAND:
 288             o = newnexus (ANDaction);
 289             o->n_L_child = n;
 290             if ((o->n_R_child = nexp1 ()))
 291                 return o;
 292             padvise (NULL, "missing conjunctive");
 293             return NULL;
 294
 295 header: ;
 296         default:
 297             prvarg ();
 298             return n;
 299     }
 300 }
 301
 302
 303 static struct nexus *
 304 nexp2 (void)
 305 {
 306     register char *cp;
 307     register struct nexus *n;
 308
 309     if ((cp = nxtarg ()) == NULL)
 310         return NULL;
 311
 312     if (*cp != '-') {
 313         prvarg ();
 314         return nexp3 ();
 315     }
 316
 317     if (*++cp == '-')
 318         goto header;
 319     switch (smatch (cp, parswit)) {
 320         case AMBIGSW:
 321             ambigsw (cp, parswit);
 322             talked++;
 323             return NULL;
 324         case UNKWNSW:
 325             fprintf (stderr, "-%s unknown\n", cp);
 326             talked++;
 327             return NULL;
 328
 329         case PRNOT:
 330             n = newnexus (NOTaction);
 331             if ((n->n_L_child = nexp3 ()))
 332                 return n;
 333             padvise (NULL, "missing negation");
 334             return NULL;
 335
 336 header: ;
 337         default:
 338             prvarg ();
 339             return nexp3 ();
 340     }
 341 }
 342
 343 static struct nexus *
 344 nexp3 (void)
 345 {
 346     int i;
 347     register char *cp, *dp;
 348     char buffer[BUFSIZ], temp[64];
 349     register struct nexus *n;
 350
 351     if ((cp = nxtarg ()) == NULL)
 352         return NULL;
 353
 354     if (*cp != '-') {
 355         padvise (NULL, "%s unexpected", cp);
 356         return NULL;
 357     }
 358
 359     if (*++cp == '-') {
 360         dp = ++cp;
 361         goto header;
 362     }
 363     switch (i = smatch (cp, parswit)) {
 364         case AMBIGSW:
 365             ambigsw (cp, parswit);
 366             talked++;
 367             return NULL;
 368         case UNKWNSW:
 369             fprintf (stderr, "-%s unknown\n", cp);
 370             talked++;
 371             return NULL;
 372
 373         case PRLBR:
 374             if ((n = parse ()) == NULL) {
 375                 padvise (NULL, "missing group");
 376                 return NULL;
 377             }
 378             if ((cp = nxtarg ()) == NULL) {
 379                 padvise (NULL, "missing -rbrace");
 380                 return NULL;
 381             }
 382             if (*cp++ == '-' && smatch (cp, parswit) == PRRBR)
 383                 return n;
 384             padvise (NULL, "%s unexpected", --cp);
 385             return NULL;
 386
 387         default:
 388             prvarg ();
 389             return NULL;
 390
 391         case PRCC:
 392         case PRDATE:
 393         case PRFROM:
 394         case PRTO:
 395         case PRSUBJ:
 396             strncpy(temp, parswit[i].sw, sizeof(temp));
 397             temp[sizeof(temp) - 1] = '\0';
 398             dp = *brkstring (temp, " ", NULL);
 399     header: ;
 400             if (!(cp = nxtarg ())) {/* allow -xyz arguments */
 401                 padvise (NULL, "missing argument to %s", argp[-2]);
 402                 return NULL;
 403             }
 404             n = newnexus (GREPaction);
 405             n->n_header = 1;
 406             snprintf (buffer, sizeof(buffer), "^%s[ \t]*:.*%s", dp, cp);
 407             dp = buffer;
 408             goto pattern;
 409
 410         case PRSRCH:
 411             n = newnexus (GREPaction);
 412             n->n_header = 0;
 413             if (!(cp = nxtarg ())) {/* allow -xyz arguments */
 414                 padvise (NULL, "missing argument to %s", argp[-2]);
 415                 return NULL;
 416             }
 417             dp = cp;
 418     pattern: ;
 419             if (!gcompile (n, dp)) {
 420                 padvise (NULL, "pattern error in %s %s", argp[-2], cp);
 421                 return NULL;
 422             }
 423             n->n_patbuf = getcpy (dp);
 424             return n;
 425
 426         case PROTHR:
 427             padvise (NULL, "internal error!");
 428             return NULL;
 429
 430         case PRDATF:
 431             if (!(datesw = nxtarg ()) || *datesw == '-') {
 432                 padvise (NULL, "missing argument to %s", argp[-2]);
 433                 return NULL;
 434             }
 435             return nexp3 ();
 436
 437         case PRAFTR:
 438         case PRBEFR:
 439             if (!(cp = nxtarg ())) {/* allow -xyz arguments */
 440                 padvise (NULL, "missing argument to %s", argp[-2]);
 441                 return NULL;
 442             }
 443             n = newnexus (TWSaction);
 444             n->n_datef = datesw;
 445             if (!tcompile (cp, &n->n_tws, n->n_after = i == PRAFTR)) {
 446                 padvise (NULL, "unable to parse %s %s", argp[-2], cp);
 447                 return NULL;
 448             }
 449             return n;
 450     }
 451 }
 452
 453
 454 static struct nexus *
 455 newnexus (int (*action)())
 456 {
 457     register struct nexus *p;
 458
 459     if ((p = (struct nexus *) calloc ((size_t) 1, sizeof *p)) == NULL)
 460         adios (NULL, "unable to allocate component storage");
 461
 462     p->n_action = action;
 463     return p;
 464 }
 465
 466
 467 #define args(a) a, fp, msgnum, start, stop
 468 #define params  args (n)
 469 #define plist   \
 470             register struct nexus  *n; \
 471             register FILE *fp; \
 472             int msgnum; \
 473             long    start, \
 474                     stop;
 475
 476 int
 477 pmatches (FILE *fp, int msgnum, long start, long stop)
 478 {
 479     if (!head)
 480         return 1;
 481
 482     if (!talked++ && pdebug)
 483         PRaction (head, 0);
 484
 485     return (*head->n_action) (args (head));
 486 }
 487
 488
 489 static void
 490 PRaction (struct nexus *n, int level)
 491 {
 492     register int i;
 493
 494     for (i = 0; i < level; i++)
 495         fprintf (stderr, "| ");
 496
 497     if (n->n_action == ORaction) {
 498         fprintf (stderr, "OR\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 == ANDaction) {
 504         fprintf (stderr, "AND\n");
 505         PRaction (n->n_L_child, level + 1);
 506         PRaction (n->n_R_child, level + 1);
 507         return;
 508     }
 509     if (n->n_action == NOTaction) {
 510         fprintf (stderr, "NOT\n");
 511         PRaction (n->n_L_child, level + 1);
 512         return;
 513     }
 514     if (n->n_action == GREPaction) {
 515         fprintf (stderr, "PATTERN(%s) %s\n",
 516                 n->n_header ? "header" : "body", n->n_patbuf);
 517         return;
 518     }
 519     if (n->n_action == TWSaction) {
 520         fprintf (stderr, "TEMPORAL(%s) %s: %s\n",
 521                 n->n_after ? "after" : "before", n->n_datef,
 522                 dasctime (&n->n_tws, TW_NULL));
 523         return;
 524     }
 525     fprintf (stderr, "UNKNOWN(0x%x)\n",
 526              (unsigned int)(unsigned long) (*n->n_action));
 527 }
 528
 529
 530 static int
 531 ORaction (params)
 532 plist
 533 {
 534     if ((*n->n_L_child->n_action) (args (n->n_L_child)))
 535         return 1;
 536     return (*n->n_R_child->n_action) (args (n->n_R_child));
 537 }
 538
 539
 540 static int
 541 ANDaction (params)
 542 plist
 543 {
 544     if (!(*n->n_L_child->n_action) (args (n->n_L_child)))
 545         return 0;
 546     return (*n->n_R_child->n_action) (args (n->n_R_child));
 547 }
 548
 549
 550 static int
 551 NOTaction (params)
 552 plist
 553 {
 554     return (!(*n->n_L_child->n_action) (args (n->n_L_child)));
 555 }
 556
 557
 558 static int
 559 gcompile (struct nexus *n, char *astr)
 560 {
 561     register int c;
 562     int cclcnt;
 563     register unsigned char *ep, *dp, *sp, *lastep = 0;
 564
 565     dp = (ep = (unsigned char *) n->n_expbuf) + sizeof n->n_expbuf;
 566     sp = (unsigned char *) astr;
 567     if (*sp == '^') {
 568         n->n_circf = 1;
 569         sp++;
 570     }
 571     else
 572         n->n_circf = 0;
 573     for (;;) {
 574         if (ep >= dp)
 575             goto cerror;
 576         if ((c = *sp++) != '*')
 577             lastep = ep;
 578         switch (c) {
 579             case '\0':
 580                 *ep++ = CEOF;
 581                 return 1;
 582
 583             case '.':
 584                 *ep++ = CDOT;
 585                 continue;
 586
 587             case '*':
 588                 if (lastep == 0)
 589                     goto defchar;
 590                 *lastep |= STAR;
 591                 continue;
 592
 593             case '$':
 594                 if (*sp != '\0')
 595                     goto defchar;
 596                 *ep++ = CDOL;
 597                 continue;
 598
 599             case '[':
 600                 *ep++ = CCL;
 601                 *ep++ = 0;
 602                 cclcnt = 0;
 603                 if ((c = *sp++) == '^') {
 604                     c = *sp++;
 605                     ep[-2] = NCCL;
 606                 }
 607                 if (c == '-') {
 608                     *ep++ = c;
 609                     cclcnt++;
 610                     c = *sp++;
 611                 }
 612                 do {
 613                     if (c == '-' && *sp != '\0' && *sp != ']') {
 614                         for (c = ep[-1]+1; c < *sp; c++) {
 615                             *ep++ = c;
 616                             cclcnt++;
 617                             if (c == '\0' || ep >= dp)
 618                                 goto cerror;
 619                         }
 620                     } else {
 621                         *ep++ = c;
 622                         cclcnt++;
 623                         if (c == '\0' || ep >= dp)
 624                             goto cerror;
 625                     }
 626                 } while ((c = *sp++) != ']');
 627                 if (cclcnt > 255)
 628                     goto cerror;
 629                 lastep[1] = cclcnt;
 630                 continue;
 631
 632             case '\\':
 633                 if ((c = *sp++) == '\0')
 634                     goto cerror;
 635         defchar:
 636             default:
 637                 *ep++ = CCHR;
 638                 *ep++ = c;
 639         }
 640     }
 641
 642 cerror: ;
 643     return 0;
 644 }
 645
 646
 647 static int
 648 GREPaction (params)
 649 plist
 650 {
 651     int c, body, lf;
 652     long pos = start;
 653     register char *p1, *p2, *ebp, *cbp;
 654     char ibuf[BUFSIZ];
 655     NMH_UNUSED (msgnum);
 656
 657     fseek (fp, start, SEEK_SET);
 658     body = 0;
 659     ebp = cbp = ibuf;
 660     for (;;) {
 661         if (body && n->n_header)
 662             return 0;
 663         p1 = linebuf;
 664         p2 = cbp;
 665         lf = 0;
 666         for (;;) {
 667             if (p2 >= ebp) {
 668                 if (fgets (ibuf, sizeof ibuf, fp) == NULL
 669                         || (stop && pos >= stop)) {
 670                     if (lf)
 671                         break;
 672                     return 0;
 673                 }
 674                 pos += (long) strlen (ibuf);
 675                 p2 = ibuf;
 676                 ebp = ibuf + strlen (ibuf);
 677             }
 678             c = *p2++;
 679             if (lf && c != '\n') {
 680                 if (c != ' ' && c != '\t') {
 681                     --p2;
 682                     break;
 683                 }
 684                 else
 685                     lf = 0;
 686             }
 687             if (c == '\n') {
 688                 if (body)
 689                     break;
 690                 else {
 691                     if (lf) {
 692                         body++;
 693                         break;
 694                     }
 695                     lf++;
 696                     /* Unfold by skipping the newline. */
 697                     c = 0;
 698                 }
 699             }
 700             if (c && p1 < &linebuf[LBSIZE - 1])
 701                 *p1++ = c;
 702         }
 703
 704         *p1++ = 0;
 705         cbp = p2;
 706         p1 = linebuf;
 707         p2 = n->n_expbuf;
 708
 709         /* Attempt to decode as a MIME header.  If it's the last header,
 710            body will be 1 and lf will be at least 1. */
 711         if ((body == 0 || lf > 0)  &&
 712             decode_rfc2047 (linebuf, decoded_linebuf, sizeof decoded_linebuf)) {
 713             p1 = decoded_linebuf;
 714         }
 715
 716         if (n->n_circf) {
 717             if (advance (p1, p2))
 718                 return 1;
 719             continue;
 720         }
 721
 722         if (*p2 == CCHR) {
 723             c = p2[1];
 724             do {
 725                 if (*p1 == c || cc[(unsigned char)*p1] == c)
 726                     if (advance (p1, p2))
 727                         return 1;
 728             } while (*p1++);
 729             continue;
 730         }
 731
 732         do {
 733             if (advance (p1, p2))
 734                 return 1;
 735         } while (*p1++);
 736     }
 737 }
 738
 739
 740 static int
 741 advance (char *alp, char *aep)
 742 {
 743     register unsigned char *lp, *ep, *curlp;
 744
 745     lp = (unsigned char *)alp;
 746     ep = (unsigned char *)aep;
 747     for (;;)
 748         switch (*ep++) {
 749             case CCHR:
 750                 if (*ep++ == *lp++ || ep[-1] == cc[lp[-1]])
 751                     continue;
 752                 return 0;
 753
 754             case CDOT:
 755                 if (*lp++)
 756                     continue;
 757                 return 0;
 758
 759             case CDOL:
 760                 if (*lp == 0)
 761                     continue;
 762                 return 0;
 763
 764             case CEOF:
 765                 return 1;
 766
 767             case CCL:
 768                 if (cclass (ep, *lp++, 1)) {
 769                     ep += *ep + 1;
 770                     continue;
 771                 }
 772                 return 0;
 773
 774             case NCCL:
 775                 if (cclass (ep, *lp++, 0)) {
 776                     ep += *ep + 1;
 777                     continue;
 778                 }
 779                 return 0;
 780
 781             case CDOT | STAR:
 782                 curlp = lp;
 783                 while (*lp++)
 784                     continue;
 785                 goto star;
 786
 787             case CCHR | STAR:
 788                 curlp = lp;
 789                 while (*lp++ == *ep || cc[lp[-1]] == *ep)
 790                     continue;
 791                 ep++;
 792                 goto star;
 793
 794             case CCL | STAR:
 795             case NCCL | STAR:
 796                 curlp = lp;
 797                 while (cclass (ep, *lp++, ep[-1] == (CCL | STAR)))
 798                     continue;
 799                 ep += *ep + 1;
 800                 goto star;
 801
 802         star:
 803                 do {
 804                     lp--;
 805                     if (advance ((char *) lp, (char *) ep))
 806                         return (1);
 807                 } while (lp > curlp);
 808                 return 0;
 809
 810             default:
 811                 admonish (NULL, "advance() botch -- you lose big");
 812                 return 0;
 813         }
 814 }
 815
 816
 817 static int
 818 cclass (unsigned char *aset, int ac, int af)
 819 {
 820     register unsigned int    n;
 821     register unsigned char   c, *set;
 822
 823     set = aset;
 824     if ((c = ac) == 0)
 825         return (0);
 826
 827     n = *set++;
 828     while (n--)
 829         if (*set++ == c || set[-1] == cc[c])
 830             return (af);
 831
 832     return (!af);
 833 }
 834
 835
 836 static int
 837 tcompile (char *ap, struct tws *tb, int isafter)
 838 {
 839     register struct tws *tw;
 840
 841     if ((tw = tws_parse (ap, isafter)) == NULL)
 842         return 0;
 843
 844     twscopy (tb, tw);
 845     return 1;
 846 }
 847
 848
 849 static struct tws *
 850 tws_parse (char *ap, int isafter)
 851 {
 852     char buffer[BUFSIZ];
 853     register struct tws *tw, *ts;
 854
 855     if ((tw = tws_special (ap)) != NULL) {
 856         tw->tw_sec = tw->tw_min = isafter ? 59 : 0;
 857         tw->tw_hour = isafter ? 23 : 0;
 858         return tw;
 859     }
 860     if ((tw = dparsetime (ap)) != NULL)
 861         return tw;
 862
 863     if ((ts = dlocaltimenow ()) == NULL)
 864         return NULL;
 865
 866     snprintf (buffer, sizeof(buffer), "%s %s", ap, dtwszone (ts));
 867     if ((tw = dparsetime (buffer)) != NULL)
 868         return tw;
 869
 870     snprintf (buffer, sizeof(buffer), "%s %02d:%02d:%02d %s", ap,
 871             ts->tw_hour, ts->tw_min, ts->tw_sec, dtwszone (ts));
 872     if ((tw = dparsetime (buffer)) != NULL)
 873         return tw;
 874
 875     snprintf (buffer, sizeof(buffer), "%02d %s %04d %s",
 876             ts->tw_mday, tw_moty[ts->tw_mon], ts->tw_year, ap);
 877     if ((tw = dparsetime (buffer)) != NULL)
 878         return tw;
 879
 880     snprintf (buffer, sizeof(buffer), "%02d %s %04d %s %s",
 881             ts->tw_mday, tw_moty[ts->tw_mon], ts->tw_year,
 882             ap, dtwszone (ts));
 883     if ((tw = dparsetime (buffer)) != NULL)
 884         return tw;
 885
 886     return NULL;
 887 }
 888
 889
 890 static struct tws *
 891 tws_special (char *ap)
 892 {
 893     int i;
 894     time_t clock;
 895     register struct tws *tw;
 896
 897     time (&clock);
 898     if (!strcasecmp (ap, "today"))
 899         return dlocaltime (&clock);
 900     if (!strcasecmp (ap, "yesterday")) {
 901         clock -= (long) (60 * 60 * 24);
 902         return dlocaltime (&clock);
 903     }
 904     if (!strcasecmp (ap, "tomorrow")) {
 905         clock += (long) (60 * 60 * 24);
 906         return dlocaltime (&clock);
 907     }
 908
 909     for (i = 0; tw_ldotw[i]; i++)
 910         if (!strcasecmp (ap, tw_ldotw[i]))
 911             break;
 912     if (tw_ldotw[i]) {
 913         if ((tw = dlocaltime (&clock)) == NULL)
 914             return NULL;
 915         if ((i -= tw->tw_wday) > 0)
 916             i -= 7;
 917     }
 918     else
 919         if (*ap != '-')
 920             return NULL;
 921         else                    /* -ddd days ago */
 922             i = atoi (ap);      /* we should error check this */
 923
 924     clock += (long) ((60 * 60 * 24) * i);
 925     return dlocaltime (&clock);
 926 }
 927
 928
 929 static int
 930 TWSaction (params)
 931 plist
 932 {
 933     int state;
 934     register char *bp;
 935     char buf[BUFSIZ], name[NAMESZ];
 936     register struct tws *tw;
 937     m_getfld_state_t gstate = 0;
 938     NMH_UNUSED (stop);
 939
 940     fseek (fp, start, SEEK_SET);
 941     for (bp = NULL;;) {
 942         int bufsz = sizeof buf;
 943         switch (state = m_getfld (&gstate, name, buf, &bufsz, fp)) {
 944             case FLD:
 945             case FLDPLUS:
 946                 if (bp != NULL)
 947                     free (bp), bp = NULL;
 948                 bp = add (buf, NULL);
 949                 while (state == FLDPLUS) {
 950                     bufsz = sizeof buf;
 951                     state = m_getfld (&gstate, name, buf, &bufsz, fp);
 952                     bp = add (buf, bp);
 953                 }
 954                 if (!strcasecmp (name, n->n_datef))
 955                     break;
 956                 continue;
 957
 958             case BODY:
 959             case FILEEOF:
 960             case LENERR:
 961             case FMTERR:
 962                 if (state == LENERR || state == FMTERR)
 963                     advise (NULL, "format error in message %d", msgnum);
 964                 if (bp != NULL)
 965                     free (bp);
 966                 return 0;
 967
 968             default:
 969                 adios (NULL, "internal error -- you lose");
 970         }
 971         break;
 972     }
 973     m_getfld_state_destroy (&gstate);
 974
 975     if ((tw = dparsetime (bp)) == NULL)
 976         advise (NULL, "unable to parse %s field in message %d, matching...",
 977                 n->n_datef, msgnum), state = 1;
 978     else
 979         state = n->n_after ? (twsort (tw, &n->n_tws) > 0)
 980             : (twsort (tw, &n->n_tws) < 0);
 981
 982     if (bp != NULL)
 983         free (bp);
 984     return state;
 985 }