mansearch.c

   1 /*      $OpenBSD: mansearch.c,v 1.50 2016/07/09 15:23:36 schwarze Exp $ */
   2 /*
   3  * Copyright (c) 2012 Kristaps Dzonsons <kristaps@bsd.lv>
   4  * Copyright (c) 2013-2017 Ingo Schwarze <schwarze@openbsd.org>
   5  *
   6  * Permission to use, copy, modify, and distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHORS DISCLAIM ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18 #include "config.h"
  19
  20 #include <sys/mman.h>
  21 #include <sys/types.h>
  22
  23 #include <assert.h>
  24 #if HAVE_ERR
  25 #include <err.h>
  26 #endif
  27 #include <errno.h>
  28 #include <fcntl.h>
  29 #include <glob.h>
  30 #include <limits.h>
  31 #include <regex.h>
  32 #include <stdio.h>
  33 #include <stdint.h>
  34 #include <stddef.h>
  35 #include <stdlib.h>
  36 #include <string.h>
  37 #include <unistd.h>
  38
  39 #include "mandoc.h"
  40 #include "mandoc_aux.h"
  41 #include "mandoc_ohash.h"
  42 #include "manconf.h"
  43 #include "mansearch.h"
  44 #include "dbm.h"
  45
  46 struct  expr {
  47         /* Used for terms: */
  48         struct dbm_match match;   /* Match type and expression. */
  49         uint64_t         bits;    /* Type mask. */
  50         /* Used for OR and AND groups: */
  51         struct expr     *next;    /* Next child in the parent group. */
  52         struct expr     *child;   /* First child in this group. */
  53         enum { EXPR_TERM, EXPR_OR, EXPR_AND } type;
  54 };
  55
  56 const char *const mansearch_keynames[KEY_MAX] = {
  57         "arch", "sec",  "Xr",   "Ar",   "Fa",   "Fl",   "Dv",   "Fn",
  58         "Ic",   "Pa",   "Cm",   "Li",   "Em",   "Cd",   "Va",   "Ft",
  59         "Tn",   "Er",   "Ev",   "Sy",   "Sh",   "In",   "Ss",   "Ox",
  60         "An",   "Mt",   "St",   "Bx",   "At",   "Nx",   "Fx",   "Lk",
  61         "Ms",   "Bsx",  "Dx",   "Rs",   "Vt",   "Lb",   "Nm",   "Nd"
  62 };
  63
  64
  65 static  struct ohash    *manmerge(struct expr *, struct ohash *);
  66 static  struct ohash    *manmerge_term(struct expr *, struct ohash *);
  67 static  struct ohash    *manmerge_or(struct expr *, struct ohash *);
  68 static  struct ohash    *manmerge_and(struct expr *, struct ohash *);
  69 static  char            *buildnames(const struct dbm_page *);
  70 static  char            *buildoutput(size_t, struct dbm_page *);
  71 static  size_t           lstlen(const char *, size_t);
  72 static  void             lstcat(char *, size_t *, const char *, const char *);
  73 static  int              lstmatch(const char *, const char *);
  74 static  struct expr     *exprcomp(const struct mansearch *,
  75                                 int, char *[], int *);
  76 static  struct expr     *expr_and(const struct mansearch *,
  77                                 int, char *[], int *);
  78 static  struct expr     *exprterm(const struct mansearch *,
  79                                 int, char *[], int *);
  80 static  void             exprfree(struct expr *);
  81 static  int              manpage_compare(const void *, const void *);
  82
  83
  84 int
  85 mansearch(const struct mansearch *search,
  86                 const struct manpaths *paths,
  87                 int argc, char *argv[],
  88                 struct manpage **res, size_t *sz)
  89 {
  90         char             buf[PATH_MAX];
  91         struct dbm_res  *rp;
  92         struct expr     *e;
  93         struct dbm_page *page;
  94         struct manpage  *mpage;
  95         struct ohash    *htab;
  96         size_t           cur, i, maxres, outkey;
  97         unsigned int     slot;
  98         int              argi, chdir_status, getcwd_status, im;
  99
 100         argi = 0;
 101         if ((e = exprcomp(search, argc, argv, &argi)) == NULL) {
 102                 *sz = 0;
 103                 return 0;
 104         }
 105
 106         cur = maxres = 0;
 107         *res = NULL;
 108
 109         outkey = KEY_Nd;
 110         if (search->outkey != NULL)
 111                 for (im = 0; im < KEY_MAX; im++)
 112                         if (0 == strcasecmp(search->outkey,
 113                             mansearch_keynames[im])) {
 114                                 outkey = im;
 115                                 break;
 116                         }
 117
 118         /*
 119          * Remember the original working directory, if possible.
 120          * This will be needed if the second or a later directory
 121          * is given as a relative path.
 122          * Do not error out if the current directory is not
 123          * searchable: Maybe it won't be needed after all.
 124          */
 125
 126         if (getcwd(buf, PATH_MAX) == NULL) {
 127                 getcwd_status = 0;
 128                 (void)strlcpy(buf, strerror(errno), sizeof(buf));
 129         } else
 130                 getcwd_status = 1;
 131
 132         /*
 133          * Loop over the directories (containing databases) for us to
 134          * search.
 135          * Don't let missing/bad databases/directories phase us.
 136          * In each, try to open the resident database and, if it opens,
 137          * scan it for our match expression.
 138          */
 139
 140         chdir_status = 0;
 141         for (i = 0; i < paths->sz; i++) {
 142                 if (chdir_status && paths->paths[i][0] != '/') {
 143                         if ( ! getcwd_status) {
 144                                 warnx("%s: getcwd: %s", paths->paths[i], buf);
 145                                 continue;
 146                         } else if (chdir(buf) == -1) {
 147                                 warn("%s", buf);
 148                                 continue;
 149                         }
 150                 }
 151                 if (chdir(paths->paths[i]) == -1) {
 152                         warn("%s", paths->paths[i]);
 153                         continue;
 154                 }
 155                 chdir_status = 1;
 156
 157                 if (dbm_open(MANDOC_DB) == -1) {
 158                         warn("%s/%s", paths->paths[i], MANDOC_DB);
 159                         continue;
 160                 }
 161
 162                 if ((htab = manmerge(e, NULL)) == NULL) {
 163                         dbm_close();
 164                         continue;
 165                 }
 166
 167                 for (rp = ohash_first(htab, &slot); rp != NULL;
 168                     rp = ohash_next(htab, &slot)) {
 169                         page = dbm_page_get(rp->page);
 170
 171                         if (lstmatch(search->sec, page->sect) == 0 ||
 172                             lstmatch(search->arch, page->arch) == 0)
 173                                 continue;
 174
 175                         if (cur + 1 > maxres) {
 176                                 maxres += 1024;
 177                                 *res = mandoc_reallocarray(*res,
 178                                     maxres, sizeof(**res));
 179                         }
 180                         mpage = *res + cur;
 181                         mandoc_asprintf(&mpage->file, "%s/%s",
 182                             paths->paths[i], page->file + 1);
 183                         mpage->names = buildnames(page);
 184                         mpage->output = buildoutput(outkey, page);
 185                         mpage->ipath = i;
 186                         mpage->bits = rp->bits;
 187                         mpage->sec = *page->sect - '0';
 188                         if (mpage->sec < 0 || mpage->sec > 9)
 189                                 mpage->sec = 10;
 190                         mpage->form = *page->file;
 191                         free(rp);
 192                         cur++;
 193                 }
 194                 ohash_delete(htab);
 195                 free(htab);
 196                 dbm_close();
 197
 198                 /*
 199                  * In man(1) mode, prefer matches in earlier trees
 200                  * over matches in later trees.
 201                  */
 202
 203                 if (cur && search->firstmatch)
 204                         break;
 205         }
 206         qsort(*res, cur, sizeof(struct manpage), manpage_compare);
 207         if (chdir_status && getcwd_status && chdir(buf) == -1)
 208                 warn("%s", buf);
 209         exprfree(e);
 210         *sz = cur;
 211         return 1;
 212 }
 213
 214 /*
 215  * Merge the results for the expression tree rooted at e
 216  * into the the result list htab.
 217  */
 218 static struct ohash *
 219 manmerge(struct expr *e, struct ohash *htab)
 220 {
 221         switch (e->type) {
 222         case EXPR_TERM:
 223                 return manmerge_term(e, htab);
 224         case EXPR_OR:
 225                 return manmerge_or(e->child, htab);
 226         case EXPR_AND:
 227                 return manmerge_and(e->child, htab);
 228         default:
 229                 abort();
 230         }
 231 }
 232
 233 static struct ohash *
 234 manmerge_term(struct expr *e, struct ohash *htab)
 235 {
 236         struct dbm_res   res, *rp;
 237         uint64_t         ib;
 238         unsigned int     slot;
 239         int              im;
 240
 241         if (htab == NULL) {
 242                 htab = mandoc_malloc(sizeof(*htab));
 243                 mandoc_ohash_init(htab, 4, offsetof(struct dbm_res, page));
 244         }
 245
 246         for (im = 0, ib = 1; im < KEY_MAX; im++, ib <<= 1) {
 247                 if ((e->bits & ib) == 0)
 248                         continue;
 249
 250                 switch (ib) {
 251                 case TYPE_arch:
 252                         dbm_page_byarch(&e->match);
 253                         break;
 254                 case TYPE_sec:
 255                         dbm_page_bysect(&e->match);
 256                         break;
 257                 case TYPE_Nm:
 258                         dbm_page_byname(&e->match);
 259                         break;
 260                 case TYPE_Nd:
 261                         dbm_page_bydesc(&e->match);
 262                         break;
 263                 default:
 264                         dbm_page_bymacro(im - 2, &e->match);
 265                         break;
 266                 }
 267
 268                 /*
 269                  * When hashing for deduplication, use the unique
 270                  * page ID itself instead of a hash function;
 271                  * that is quite efficient.
 272                  */
 273
 274                 for (;;) {
 275                         res = dbm_page_next();
 276                         if (res.page == -1)
 277                                 break;
 278                         slot = ohash_lookup_memory(htab,
 279                             (char *)&res, sizeof(res.page), res.page);
 280                         if ((rp = ohash_find(htab, slot)) != NULL) {
 281                                 rp->bits |= res.bits;
 282                                 continue;
 283                         }
 284                         rp = mandoc_malloc(sizeof(*rp));
 285                         *rp = res;
 286                         ohash_insert(htab, slot, rp);
 287                 }
 288         }
 289         return htab;
 290 }
 291
 292 static struct ohash *
 293 manmerge_or(struct expr *e, struct ohash *htab)
 294 {
 295         while (e != NULL) {
 296                 htab = manmerge(e, htab);
 297                 e = e->next;
 298         }
 299         return htab;
 300 }
 301
 302 static struct ohash *
 303 manmerge_and(struct expr *e, struct ohash *htab)
 304 {
 305         struct ohash    *hand, *h1, *h2;
 306         struct dbm_res  *res;
 307         unsigned int     slot1, slot2;
 308
 309         /* Evaluate the first term of the AND clause. */
 310
 311         hand = manmerge(e, NULL);
 312
 313         while ((e = e->next) != NULL) {
 314
 315                 /* Evaluate the next term and prepare for ANDing. */
 316
 317                 h2 = manmerge(e, NULL);
 318                 if (ohash_entries(h2) < ohash_entries(hand)) {
 319                         h1 = h2;
 320                         h2 = hand;
 321                 } else
 322                         h1 = hand;
 323                 hand = mandoc_malloc(sizeof(*hand));
 324                 mandoc_ohash_init(hand, 4, offsetof(struct dbm_res, page));
 325
 326                 /* Keep all pages that are in both result sets. */
 327
 328                 for (res = ohash_first(h1, &slot1); res != NULL;
 329                     res = ohash_next(h1, &slot1)) {
 330                         if (ohash_find(h2, ohash_lookup_memory(h2,
 331                             (char *)res, sizeof(res->page),
 332                             res->page)) == NULL)
 333                                 free(res);
 334                         else
 335                                 ohash_insert(hand, ohash_lookup_memory(hand,
 336                                     (char *)res, sizeof(res->page),
 337                                     res->page), res);
 338                 }
 339
 340                 /* Discard the merged results. */
 341
 342                 for (res = ohash_first(h2, &slot2); res != NULL;
 343                     res = ohash_next(h2, &slot2))
 344                         free(res);
 345                 ohash_delete(h2);
 346                 free(h2);
 347                 ohash_delete(h1);
 348                 free(h1);
 349         }
 350
 351         /* Merge the result of the AND into htab. */
 352
 353         if (htab == NULL)
 354                 return hand;
 355
 356         for (res = ohash_first(hand, &slot1); res != NULL;
 357             res = ohash_next(hand, &slot1)) {
 358                 slot2 = ohash_lookup_memory(htab,
 359                     (char *)res, sizeof(res->page), res->page);
 360                 if (ohash_find(htab, slot2) == NULL)
 361                         ohash_insert(htab, slot2, res);
 362                 else
 363                         free(res);
 364         }
 365
 366         /* Discard the merged result. */
 367
 368         ohash_delete(hand);
 369         free(hand);
 370         return htab;
 371 }
 372
 373 void
 374 mansearch_free(struct manpage *res, size_t sz)
 375 {
 376         size_t   i;
 377
 378         for (i = 0; i < sz; i++) {
 379                 free(res[i].file);
 380                 free(res[i].names);
 381                 free(res[i].output);
 382         }
 383         free(res);
 384 }
 385
 386 static int
 387 manpage_compare(const void *vp1, const void *vp2)
 388 {
 389         const struct manpage    *mp1, *mp2;
 390         int                      diff;
 391
 392         mp1 = vp1;
 393         mp2 = vp2;
 394         return (diff = mp2->bits - mp1->bits) ? diff :
 395             (diff = mp1->sec - mp2->sec) ? diff :
 396             strcasecmp(mp1->names, mp2->names);
 397 }
 398
 399 static char *
 400 buildnames(const struct dbm_page *page)
 401 {
 402         char    *buf;
 403         size_t   i, sz;
 404
 405         sz = lstlen(page->name, 2) + 1 + lstlen(page->sect, 2) +
 406             (page->arch == NULL ? 0 : 1 + lstlen(page->arch, 2)) + 2;
 407         buf = mandoc_malloc(sz);
 408         i = 0;
 409         lstcat(buf, &i, page->name, ", ");
 410         buf[i++] = '(';
 411         lstcat(buf, &i, page->sect, ", ");
 412         if (page->arch != NULL) {
 413                 buf[i++] = '/';
 414                 lstcat(buf, &i, page->arch, ", ");
 415         }
 416         buf[i++] = ')';
 417         buf[i++] = '\0';
 418         assert(i == sz);
 419         return buf;
 420 }
 421
 422 /*
 423  * Count the buffer space needed to print the NUL-terminated
 424  * list of NUL-terminated strings, when printing sep separator
 425  * characters between strings.
 426  */
 427 static size_t
 428 lstlen(const char *cp, size_t sep)
 429 {
 430         size_t   sz;
 431
 432         for (sz = 0;; sz++) {
 433                 if (cp[0] == '\0') {
 434                         if (cp[1] == '\0')
 435                                 break;
 436                         sz += sep - 1;
 437                 } else if (cp[0] < ' ')
 438                         sz--;
 439                 cp++;
 440         }
 441         return sz;
 442 }
 443
 444 /*
 445  * Print the NUL-terminated list of NUL-terminated strings
 446  * into the buffer, seperating strings with sep.
 447  */
 448 static void
 449 lstcat(char *buf, size_t *i, const char *cp, const char *sep)
 450 {
 451         const char *s;
 452
 453         for (;;) {
 454                 if (cp[0] == '\0') {
 455                         if (cp[1] == '\0')
 456                                 break;
 457                         s = sep;
 458                         while (*s != '\0')
 459                                 buf[(*i)++] = *s++;
 460                 } else if (cp[0] >= ' ')
 461                         buf[(*i)++] = cp[0];
 462                 cp++;
 463         }
 464 }
 465
 466 /*
 467  * Return 1 if the string *want occurs in any of the strings
 468  * in the NUL-terminated string list *have, or 0 otherwise.
 469  * If either argument is NULL or empty, assume no filtering
 470  * is desired and return 1.
 471  */
 472 static int
 473 lstmatch(const char *want, const char *have)
 474 {
 475         if (want == NULL || have == NULL || *have == '\0')
 476                 return 1;
 477         while (*have != '\0') {
 478                 if (strcasestr(have, want) != NULL)
 479                         return 1;
 480                 have = strchr(have, '\0') + 1;
 481         }
 482         return 0;
 483 }
 484
 485 /*
 486  * Build a list of values taken by the macro im in the manual page.
 487  */
 488 static char *
 489 buildoutput(size_t im, struct dbm_page *page)
 490 {
 491         const char      *oldoutput, *sep, *input;
 492         char            *output, *newoutput, *value;
 493         size_t           sz, i;
 494
 495         switch (im) {
 496         case KEY_Nd:
 497                 return mandoc_strdup(page->desc);
 498         case KEY_Nm:
 499                 input = page->name;
 500                 break;
 501         case KEY_sec:
 502                 input = page->sect;
 503                 break;
 504         case KEY_arch:
 505                 input = page->arch;
 506                 if (input == NULL)
 507                         input = "all\0";
 508                 break;
 509         default:
 510                 input = NULL;
 511                 break;
 512         }
 513
 514         if (input != NULL) {
 515                 sz = lstlen(input, 3) + 1;
 516                 output = mandoc_malloc(sz);
 517                 i = 0;
 518                 lstcat(output, &i, input, " # ");
 519                 output[i++] = '\0';
 520                 assert(i == sz);
 521                 return output;
 522         }
 523
 524         output = NULL;
 525         dbm_macro_bypage(im - 2, page->addr);
 526         while ((value = dbm_macro_next()) != NULL) {
 527                 if (output == NULL) {
 528                         oldoutput = "";
 529                         sep = "";
 530                 } else {
 531                         oldoutput = output;
 532                         sep = " # ";
 533                 }
 534                 mandoc_asprintf(&newoutput, "%s%s%s", oldoutput, sep, value);
 535                 free(output);
 536                 output = newoutput;
 537         }
 538         return output;
 539 }
 540
 541 /*
 542  * Compile a set of string tokens into an expression.
 543  * Tokens in "argv" are assumed to be individual expression atoms (e.g.,
 544  * "(", "foo=bar", etc.).
 545  */
 546 static struct expr *
 547 exprcomp(const struct mansearch *search, int argc, char *argv[], int *argi)
 548 {
 549         struct expr     *parent, *child;
 550         int              needterm, nested;
 551
 552         if ((nested = *argi) == argc)
 553                 return NULL;
 554         needterm = 1;
 555         parent = child = NULL;
 556         while (*argi < argc) {
 557                 if (strcmp(")", argv[*argi]) == 0) {
 558                         if (needterm)
 559                                 warnx("missing term "
 560                                     "before closing parenthesis");
 561                         needterm = 0;
 562                         if (nested)
 563                                 break;
 564                         warnx("ignoring unmatched right parenthesis");
 565                         ++*argi;
 566                         continue;
 567                 }
 568                 if (strcmp("-o", argv[*argi]) == 0) {
 569                         if (needterm) {
 570                                 if (*argi > 0)
 571                                         warnx("ignoring -o after %s",
 572                                             argv[*argi - 1]);
 573                                 else
 574                                         warnx("ignoring initial -o");
 575                         }
 576                         needterm = 1;
 577                         ++*argi;
 578                         continue;
 579                 }
 580                 needterm = 0;
 581                 if (child == NULL) {
 582                         child = expr_and(search, argc, argv, argi);
 583                         continue;
 584                 }
 585                 if (parent == NULL) {
 586                         parent = mandoc_calloc(1, sizeof(*parent));
 587                         parent->type = EXPR_OR;
 588                         parent->next = NULL;
 589                         parent->child = child;
 590                 }
 591                 child->next = expr_and(search, argc, argv, argi);
 592                 child = child->next;
 593         }
 594         if (needterm && *argi)
 595                 warnx("ignoring trailing %s", argv[*argi - 1]);
 596         return parent == NULL ? child : parent;
 597 }
 598
 599 static struct expr *
 600 expr_and(const struct mansearch *search, int argc, char *argv[], int *argi)
 601 {
 602         struct expr     *parent, *child;
 603         int              needterm;
 604
 605         needterm = 1;
 606         parent = child = NULL;
 607         while (*argi < argc) {
 608                 if (strcmp(")", argv[*argi]) == 0) {
 609                         if (needterm)
 610                                 warnx("missing term "
 611                                     "before closing parenthesis");
 612                         needterm = 0;
 613                         break;
 614                 }
 615                 if (strcmp("-o", argv[*argi]) == 0)
 616                         break;
 617                 if (strcmp("-a", argv[*argi]) == 0) {
 618                         if (needterm) {
 619                                 if (*argi > 0)
 620                                         warnx("ignoring -a after %s",
 621                                             argv[*argi - 1]);
 622                                 else
 623                                         warnx("ignoring initial -a");
 624                         }
 625                         needterm = 1;
 626                         ++*argi;
 627                         continue;
 628                 }
 629                 if (needterm == 0)
 630                         break;
 631                 if (child == NULL) {
 632                         child = exprterm(search, argc, argv, argi);
 633                         if (child != NULL)
 634                                 needterm = 0;
 635                         continue;
 636                 }
 637                 needterm = 0;
 638                 if (parent == NULL) {
 639                         parent = mandoc_calloc(1, sizeof(*parent));
 640                         parent->type = EXPR_AND;
 641                         parent->next = NULL;
 642                         parent->child = child;
 643                 }
 644                 child->next = exprterm(search, argc, argv, argi);
 645                 if (child->next != NULL) {
 646                         child = child->next;
 647                         needterm = 0;
 648                 }
 649         }
 650         if (needterm && *argi)
 651                 warnx("ignoring trailing %s", argv[*argi - 1]);
 652         return parent == NULL ? child : parent;
 653 }
 654
 655 static struct expr *
 656 exprterm(const struct mansearch *search, int argc, char *argv[], int *argi)
 657 {
 658         char             errbuf[BUFSIZ];
 659         struct expr     *e;
 660         char            *key, *val;
 661         uint64_t         iterbit;
 662         int              cs, i, irc;
 663
 664         if (strcmp("(", argv[*argi]) == 0) {
 665                 ++*argi;
 666                 e = exprcomp(search, argc, argv, argi);
 667                 if (*argi < argc) {
 668                         assert(strcmp(")", argv[*argi]) == 0);
 669                         ++*argi;
 670                 } else
 671                         warnx("unclosed parenthesis");
 672                 return e;
 673         }
 674
 675         if (strcmp("-i", argv[*argi]) == 0 && *argi + 1 < argc) {
 676                 cs = 0;
 677                 ++*argi;
 678         } else
 679                 cs = 1;
 680
 681         e = mandoc_calloc(1, sizeof(*e));
 682         e->type = EXPR_TERM;
 683         e->bits = 0;
 684         e->next = NULL;
 685         e->child = NULL;
 686
 687         if (search->argmode == ARG_NAME) {
 688                 e->bits = TYPE_Nm;
 689                 e->match.type = DBM_EXACT;
 690                 e->match.str = argv[(*argi)++];
 691                 return e;
 692         }
 693
 694         /*
 695          * Separate macro keys from search string.
 696          * If needed, request regular expression handling.
 697          */
 698
 699         if (search->argmode == ARG_WORD) {
 700                 e->bits = TYPE_Nm;
 701                 e->match.type = DBM_REGEX;
 702 #if HAVE_REWB_BSD
 703                 mandoc_asprintf(&val, "[[:<:]]%s[[:>:]]", argv[*argi]);
 704 #elif HAVE_REWB_SYSV
 705                 mandoc_asprintf(&val, "\\<%s\\>", argv[*argi]);
 706 #else
 707                 mandoc_asprintf(&val,
 708                     "(^|[^a-zA-Z01-9_])%s([^a-zA-Z01-9_]|$)", argv[*argi]);
 709 #endif
 710                 cs = 0;
 711         } else if ((val = strpbrk(argv[*argi], "=~")) == NULL) {
 712                 e->bits = TYPE_Nm | TYPE_Nd;
 713                 e->match.type = DBM_SUB;
 714                 e->match.str = argv[*argi];
 715         } else {
 716                 if (val == argv[*argi])
 717                         e->bits = TYPE_Nm | TYPE_Nd;
 718                 if (*val == '=') {
 719                         e->match.type = DBM_SUB;
 720                         e->match.str = val + 1;
 721                 } else
 722                         e->match.type = DBM_REGEX;
 723                 *val++ = '\0';
 724                 if (strstr(argv[*argi], "arch") != NULL)
 725                         cs = 0;
 726         }
 727
 728         /* Compile regular expressions. */
 729
 730         if (e->match.type == DBM_REGEX) {
 731                 e->match.re = mandoc_malloc(sizeof(*e->match.re));
 732                 irc = regcomp(e->match.re, val,
 733                     REG_EXTENDED | REG_NOSUB | (cs ? 0 : REG_ICASE));
 734                 if (irc) {
 735                         regerror(irc, e->match.re, errbuf, sizeof(errbuf));
 736                         warnx("regcomp /%s/: %s", val, errbuf);
 737                 }
 738                 if (search->argmode == ARG_WORD)
 739                         free(val);
 740                 if (irc) {
 741                         free(e->match.re);
 742                         free(e);
 743                         ++*argi;
 744                         return NULL;
 745                 }
 746         }
 747
 748         if (e->bits) {
 749                 ++*argi;
 750                 return e;
 751         }
 752
 753         /*
 754          * Parse out all possible fields.
 755          * If the field doesn't resolve, bail.
 756          */
 757
 758         while (NULL != (key = strsep(&argv[*argi], ","))) {
 759                 if ('\0' == *key)
 760                         continue;
 761                 for (i = 0, iterbit = 1; i < KEY_MAX; i++, iterbit <<= 1) {
 762                         if (0 == strcasecmp(key, mansearch_keynames[i])) {
 763                                 e->bits |= iterbit;
 764                                 break;
 765                         }
 766                 }
 767                 if (i == KEY_MAX) {
 768                         if (strcasecmp(key, "any"))
 769                                 warnx("treating unknown key "
 770                                     "\"%s\" as \"any\"", key);
 771                         e->bits |= ~0ULL;
 772                 }
 773         }
 774
 775         ++*argi;
 776         return e;
 777 }
 778
 779 static void
 780 exprfree(struct expr *e)
 781 {
 782         if (e->next != NULL)
 783                 exprfree(e->next);
 784         if (e->child != NULL)
 785                 exprfree(e->child);
 786         free(e);
 787 }