mansearch.c

   1 /*      $Id: mansearch.c,v 1.79 2018/11/22 12:01:46 schwarze Exp $ */
   2 /*
   3  * Copyright (c) 2012 Kristaps Dzonsons <kristaps@bsd.lv>
   4  * Copyright (c) 2013-2018 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         if (res != NULL)
 108                 *res = NULL;
 109
 110         outkey = KEY_Nd;
 111         if (search->outkey != NULL)
 112                 for (im = 0; im < KEY_MAX; im++)
 113                         if (0 == strcasecmp(search->outkey,
 114                             mansearch_keynames[im])) {
 115                                 outkey = im;
 116                                 break;
 117                         }
 118
 119         /*
 120          * Remember the original working directory, if possible.
 121          * This will be needed if the second or a later directory
 122          * is given as a relative path.
 123          * Do not error out if the current directory is not
 124          * searchable: Maybe it won't be needed after all.
 125          */
 126
 127         if (getcwd(buf, PATH_MAX) == NULL) {
 128                 getcwd_status = 0;
 129                 (void)strlcpy(buf, strerror(errno), sizeof(buf));
 130         } else
 131                 getcwd_status = 1;
 132
 133         /*
 134          * Loop over the directories (containing databases) for us to
 135          * search.
 136          * Don't let missing/bad databases/directories phase us.
 137          * In each, try to open the resident database and, if it opens,
 138          * scan it for our match expression.
 139          */
 140
 141         chdir_status = 0;
 142         for (i = 0; i < paths->sz; i++) {
 143                 if (chdir_status && paths->paths[i][0] != '/') {
 144                         if ( ! getcwd_status) {
 145                                 warnx("%s: getcwd: %s", paths->paths[i], buf);
 146                                 continue;
 147                         } else if (chdir(buf) == -1) {
 148                                 warn("%s", buf);
 149                                 continue;
 150                         }
 151                 }
 152                 if (chdir(paths->paths[i]) == -1) {
 153                         warn("%s", paths->paths[i]);
 154                         continue;
 155                 }
 156                 chdir_status = 1;
 157
 158                 if (dbm_open(MANDOC_DB) == -1) {
 159                         if (errno != ENOENT)
 160                                 warn("%s/%s", paths->paths[i], MANDOC_DB);
 161                         continue;
 162                 }
 163
 164                 if ((htab = manmerge(e, NULL)) == NULL) {
 165                         dbm_close();
 166                         continue;
 167                 }
 168
 169                 for (rp = ohash_first(htab, &slot); rp != NULL;
 170                     rp = ohash_next(htab, &slot)) {
 171                         page = dbm_page_get(rp->page);
 172
 173                         if (lstmatch(search->sec, page->sect) == 0 ||
 174                             lstmatch(search->arch, page->arch) == 0 ||
 175                             (search->argmode == ARG_NAME &&
 176                              rp->bits <= (int32_t)(NAME_SYN & NAME_MASK)))
 177                                 continue;
 178
 179                         if (res == NULL) {
 180                                 cur = 1;
 181                                 break;
 182                         }
 183                         if (cur + 1 > maxres) {
 184                                 maxres += 1024;
 185                                 *res = mandoc_reallocarray(*res,
 186                                     maxres, sizeof(**res));
 187                         }
 188                         mpage = *res + cur;
 189                         mandoc_asprintf(&mpage->file, "%s/%s",
 190                             paths->paths[i], page->file + 1);
 191                         if (access(chdir_status ? page->file + 1 :
 192                             mpage->file, R_OK) == -1) {
 193                                 warn("%s", mpage->file);
 194                                 warnx("outdated mandoc.db contains "
 195                                     "bogus %s entry, run makewhatis %s",
 196                                     page->file + 1, paths->paths[i]);
 197                                 free(mpage->file);
 198                                 free(rp);
 199                                 continue;
 200                         }
 201                         mpage->names = buildnames(page);
 202                         mpage->output = buildoutput(outkey, page);
 203                         mpage->ipath = i;
 204                         mpage->sec = *page->sect - '0';
 205                         if (mpage->sec < 0 || mpage->sec > 9)
 206                                 mpage->sec = 10;
 207                         mpage->form = *page->file;
 208                         free(rp);
 209                         cur++;
 210                 }
 211                 ohash_delete(htab);
 212                 free(htab);
 213                 dbm_close();
 214
 215                 /*
 216                  * In man(1) mode, prefer matches in earlier trees
 217                  * over matches in later trees.
 218                  */
 219
 220                 if (cur && search->firstmatch)
 221                         break;
 222         }
 223         if (res != NULL)
 224                 qsort(*res, cur, sizeof(struct manpage), manpage_compare);
 225         if (chdir_status && getcwd_status && chdir(buf) == -1)
 226                 warn("%s", buf);
 227         exprfree(e);
 228         *sz = cur;
 229         return res != NULL || cur;
 230 }
 231
 232 /*
 233  * Merge the results for the expression tree rooted at e
 234  * into the the result list htab.
 235  */
 236 static struct ohash *
 237 manmerge(struct expr *e, struct ohash *htab)
 238 {
 239         switch (e->type) {
 240         case EXPR_TERM:
 241                 return manmerge_term(e, htab);
 242         case EXPR_OR:
 243                 return manmerge_or(e->child, htab);
 244         case EXPR_AND:
 245                 return manmerge_and(e->child, htab);
 246         default:
 247                 abort();
 248         }
 249 }
 250
 251 static struct ohash *
 252 manmerge_term(struct expr *e, struct ohash *htab)
 253 {
 254         struct dbm_res   res, *rp;
 255         uint64_t         ib;
 256         unsigned int     slot;
 257         int              im;
 258
 259         if (htab == NULL) {
 260                 htab = mandoc_malloc(sizeof(*htab));
 261                 mandoc_ohash_init(htab, 4, offsetof(struct dbm_res, page));
 262         }
 263
 264         for (im = 0, ib = 1; im < KEY_MAX; im++, ib <<= 1) {
 265                 if ((e->bits & ib) == 0)
 266                         continue;
 267
 268                 switch (ib) {
 269                 case TYPE_arch:
 270                         dbm_page_byarch(&e->match);
 271                         break;
 272                 case TYPE_sec:
 273                         dbm_page_bysect(&e->match);
 274                         break;
 275                 case TYPE_Nm:
 276                         dbm_page_byname(&e->match);
 277                         break;
 278                 case TYPE_Nd:
 279                         dbm_page_bydesc(&e->match);
 280                         break;
 281                 default:
 282                         dbm_page_bymacro(im - 2, &e->match);
 283                         break;
 284                 }
 285
 286                 /*
 287                  * When hashing for deduplication, use the unique
 288                  * page ID itself instead of a hash function;
 289                  * that is quite efficient.
 290                  */
 291
 292                 for (;;) {
 293                         res = dbm_page_next();
 294                         if (res.page == -1)
 295                                 break;
 296                         slot = ohash_lookup_memory(htab,
 297                             (char *)&res, sizeof(res.page), res.page);
 298                         if ((rp = ohash_find(htab, slot)) != NULL)
 299                                 continue;
 300                         rp = mandoc_malloc(sizeof(*rp));
 301                         *rp = res;
 302                         ohash_insert(htab, slot, rp);
 303                 }
 304         }
 305         return htab;
 306 }
 307
 308 static struct ohash *
 309 manmerge_or(struct expr *e, struct ohash *htab)
 310 {
 311         while (e != NULL) {
 312                 htab = manmerge(e, htab);
 313                 e = e->next;
 314         }
 315         return htab;
 316 }
 317
 318 static struct ohash *
 319 manmerge_and(struct expr *e, struct ohash *htab)
 320 {
 321         struct ohash    *hand, *h1, *h2;
 322         struct dbm_res  *res;
 323         unsigned int     slot1, slot2;
 324
 325         /* Evaluate the first term of the AND clause. */
 326
 327         hand = manmerge(e, NULL);
 328
 329         while ((e = e->next) != NULL) {
 330
 331                 /* Evaluate the next term and prepare for ANDing. */
 332
 333                 h2 = manmerge(e, NULL);
 334                 if (ohash_entries(h2) < ohash_entries(hand)) {
 335                         h1 = h2;
 336                         h2 = hand;
 337                 } else
 338                         h1 = hand;
 339                 hand = mandoc_malloc(sizeof(*hand));
 340                 mandoc_ohash_init(hand, 4, offsetof(struct dbm_res, page));
 341
 342                 /* Keep all pages that are in both result sets. */
 343
 344                 for (res = ohash_first(h1, &slot1); res != NULL;
 345                     res = ohash_next(h1, &slot1)) {
 346                         if (ohash_find(h2, ohash_lookup_memory(h2,
 347                             (char *)res, sizeof(res->page),
 348                             res->page)) == NULL)
 349                                 free(res);
 350                         else
 351                                 ohash_insert(hand, ohash_lookup_memory(hand,
 352                                     (char *)res, sizeof(res->page),
 353                                     res->page), res);
 354                 }
 355
 356                 /* Discard the merged results. */
 357
 358                 for (res = ohash_first(h2, &slot2); res != NULL;
 359                     res = ohash_next(h2, &slot2))
 360                         free(res);
 361                 ohash_delete(h2);
 362                 free(h2);
 363                 ohash_delete(h1);
 364                 free(h1);
 365         }
 366
 367         /* Merge the result of the AND into htab. */
 368
 369         if (htab == NULL)
 370                 return hand;
 371
 372         for (res = ohash_first(hand, &slot1); res != NULL;
 373             res = ohash_next(hand, &slot1)) {
 374                 slot2 = ohash_lookup_memory(htab,
 375                     (char *)res, sizeof(res->page), res->page);
 376                 if (ohash_find(htab, slot2) == NULL)
 377                         ohash_insert(htab, slot2, res);
 378                 else
 379                         free(res);
 380         }
 381
 382         /* Discard the merged result. */
 383
 384         ohash_delete(hand);
 385         free(hand);
 386         return htab;
 387 }
 388
 389 void
 390 mansearch_free(struct manpage *res, size_t sz)
 391 {
 392         size_t   i;
 393
 394         for (i = 0; i < sz; i++) {
 395                 free(res[i].file);
 396                 free(res[i].names);
 397                 free(res[i].output);
 398         }
 399         free(res);
 400 }
 401
 402 static int
 403 manpage_compare(const void *vp1, const void *vp2)
 404 {
 405         const struct manpage    *mp1, *mp2;
 406         const char              *cp1, *cp2;
 407         size_t                   sz1, sz2;
 408         int                      diff;
 409
 410         mp1 = vp1;
 411         mp2 = vp2;
 412         if ((diff = mp1->sec - mp2->sec))
 413                 return diff;
 414
 415         /* Fall back to alphabetic ordering of names. */
 416         sz1 = strcspn(mp1->names, "(");
 417         sz2 = strcspn(mp2->names, "(");
 418         if (sz1 < sz2)
 419                 sz1 = sz2;
 420         if ((diff = strncasecmp(mp1->names, mp2->names, sz1)))
 421                 return diff;
 422
 423         /* For identical names and sections, prefer arch-dependent. */
 424         cp1 = strchr(mp1->names + sz1, '/');
 425         cp2 = strchr(mp2->names + sz2, '/');
 426         return cp1 != NULL && cp2 != NULL ? strcasecmp(cp1, cp2) :
 427             cp1 != NULL ? -1 : cp2 != NULL ? 1 : 0;
 428 }
 429
 430 static char *
 431 buildnames(const struct dbm_page *page)
 432 {
 433         char    *buf;
 434         size_t   i, sz;
 435
 436         sz = lstlen(page->name, 2) + 1 + lstlen(page->sect, 2) +
 437             (page->arch == NULL ? 0 : 1 + lstlen(page->arch, 2)) + 2;
 438         buf = mandoc_malloc(sz);
 439         i = 0;
 440         lstcat(buf, &i, page->name, ", ");
 441         buf[i++] = '(';
 442         lstcat(buf, &i, page->sect, ", ");
 443         if (page->arch != NULL) {
 444                 buf[i++] = '/';
 445                 lstcat(buf, &i, page->arch, ", ");
 446         }
 447         buf[i++] = ')';
 448         buf[i++] = '\0';
 449         assert(i == sz);
 450         return buf;
 451 }
 452
 453 /*
 454  * Count the buffer space needed to print the NUL-terminated
 455  * list of NUL-terminated strings, when printing sep separator
 456  * characters between strings.
 457  */
 458 static size_t
 459 lstlen(const char *cp, size_t sep)
 460 {
 461         size_t   sz;
 462
 463         for (sz = 0; *cp != '\0'; cp++) {
 464
 465                 /* Skip names appearing only in the SYNOPSIS. */
 466                 if (*cp <= (char)(NAME_SYN & NAME_MASK)) {
 467                         while (*cp != '\0')
 468                                 cp++;
 469                         continue;
 470                 }
 471
 472                 /* Skip name class markers. */
 473                 if (*cp < ' ')
 474                         cp++;
 475
 476                 /* Print a separator before each but the first string. */
 477                 if (sz)
 478                         sz += sep;
 479
 480                 /* Copy one string. */
 481                 while (*cp != '\0') {
 482                         sz++;
 483                         cp++;
 484                 }
 485         }
 486         return sz;
 487 }
 488
 489 /*
 490  * Print the NUL-terminated list of NUL-terminated strings
 491  * into the buffer, seperating strings with sep.
 492  */
 493 static void
 494 lstcat(char *buf, size_t *i, const char *cp, const char *sep)
 495 {
 496         const char      *s;
 497         size_t           i_start;
 498
 499         for (i_start = *i; *cp != '\0'; cp++) {
 500
 501                 /* Skip names appearing only in the SYNOPSIS. */
 502                 if (*cp <= (char)(NAME_SYN & NAME_MASK)) {
 503                         while (*cp != '\0')
 504                                 cp++;
 505                         continue;
 506                 }
 507
 508                 /* Skip name class markers. */
 509                 if (*cp < ' ')
 510                         cp++;
 511
 512                 /* Print a separator before each but the first string. */
 513                 if (*i > i_start) {
 514                         s = sep;
 515                         while (*s != '\0')
 516                                 buf[(*i)++] = *s++;
 517                 }
 518
 519                 /* Copy one string. */
 520                 while (*cp != '\0')
 521                         buf[(*i)++] = *cp++;
 522         }
 523
 524 }
 525
 526 /*
 527  * Return 1 if the string *want occurs in any of the strings
 528  * in the NUL-terminated string list *have, or 0 otherwise.
 529  * If either argument is NULL or empty, assume no filtering
 530  * is desired and return 1.
 531  */
 532 static int
 533 lstmatch(const char *want, const char *have)
 534 {
 535         if (want == NULL || have == NULL || *have == '\0')
 536                 return 1;
 537         while (*have != '\0') {
 538                 if (strcasestr(have, want) != NULL)
 539                         return 1;
 540                 have = strchr(have, '\0') + 1;
 541         }
 542         return 0;
 543 }
 544
 545 /*
 546  * Build a list of values taken by the macro im in the manual page.
 547  */
 548 static char *
 549 buildoutput(size_t im, struct dbm_page *page)
 550 {
 551         const char      *oldoutput, *sep, *input;
 552         char            *output, *newoutput, *value;
 553         size_t           sz, i;
 554
 555         switch (im) {
 556         case KEY_Nd:
 557                 return mandoc_strdup(page->desc);
 558         case KEY_Nm:
 559                 input = page->name;
 560                 break;
 561         case KEY_sec:
 562                 input = page->sect;
 563                 break;
 564         case KEY_arch:
 565                 input = page->arch;
 566                 if (input == NULL)
 567                         input = "all\0";
 568                 break;
 569         default:
 570                 input = NULL;
 571                 break;
 572         }
 573
 574         if (input != NULL) {
 575                 sz = lstlen(input, 3) + 1;
 576                 output = mandoc_malloc(sz);
 577                 i = 0;
 578                 lstcat(output, &i, input, " # ");
 579                 output[i++] = '\0';
 580                 assert(i == sz);
 581                 return output;
 582         }
 583
 584         output = NULL;
 585         dbm_macro_bypage(im - 2, page->addr);
 586         while ((value = dbm_macro_next()) != NULL) {
 587                 if (output == NULL) {
 588                         oldoutput = "";
 589                         sep = "";
 590                 } else {
 591                         oldoutput = output;
 592                         sep = " # ";
 593                 }
 594                 mandoc_asprintf(&newoutput, "%s%s%s", oldoutput, sep, value);
 595                 free(output);
 596                 output = newoutput;
 597         }
 598         return output;
 599 }
 600
 601 /*
 602  * Compile a set of string tokens into an expression.
 603  * Tokens in "argv" are assumed to be individual expression atoms (e.g.,
 604  * "(", "foo=bar", etc.).
 605  */
 606 static struct expr *
 607 exprcomp(const struct mansearch *search, int argc, char *argv[], int *argi)
 608 {
 609         struct expr     *parent, *child;
 610         int              needterm, nested;
 611
 612         if ((nested = *argi) == argc)
 613                 return NULL;
 614         needterm = 1;
 615         parent = child = NULL;
 616         while (*argi < argc) {
 617                 if (strcmp(")", argv[*argi]) == 0) {
 618                         if (needterm)
 619                                 warnx("missing term "
 620                                     "before closing parenthesis");
 621                         needterm = 0;
 622                         if (nested)
 623                                 break;
 624                         warnx("ignoring unmatched right parenthesis");
 625                         ++*argi;
 626                         continue;
 627                 }
 628                 if (strcmp("-o", argv[*argi]) == 0) {
 629                         if (needterm) {
 630                                 if (*argi > 0)
 631                                         warnx("ignoring -o after %s",
 632                                             argv[*argi - 1]);
 633                                 else
 634                                         warnx("ignoring initial -o");
 635                         }
 636                         needterm = 1;
 637                         ++*argi;
 638                         continue;
 639                 }
 640                 needterm = 0;
 641                 if (child == NULL) {
 642                         child = expr_and(search, argc, argv, argi);
 643                         continue;
 644                 }
 645                 if (parent == NULL) {
 646                         parent = mandoc_calloc(1, sizeof(*parent));
 647                         parent->type = EXPR_OR;
 648                         parent->next = NULL;
 649                         parent->child = child;
 650                 }
 651                 child->next = expr_and(search, argc, argv, argi);
 652                 child = child->next;
 653         }
 654         if (needterm && *argi)
 655                 warnx("ignoring trailing %s", argv[*argi - 1]);
 656         return parent == NULL ? child : parent;
 657 }
 658
 659 static struct expr *
 660 expr_and(const struct mansearch *search, int argc, char *argv[], int *argi)
 661 {
 662         struct expr     *parent, *child;
 663         int              needterm;
 664
 665         needterm = 1;
 666         parent = child = NULL;
 667         while (*argi < argc) {
 668                 if (strcmp(")", argv[*argi]) == 0) {
 669                         if (needterm)
 670                                 warnx("missing term "
 671                                     "before closing parenthesis");
 672                         needterm = 0;
 673                         break;
 674                 }
 675                 if (strcmp("-o", argv[*argi]) == 0)
 676                         break;
 677                 if (strcmp("-a", argv[*argi]) == 0) {
 678                         if (needterm) {
 679                                 if (*argi > 0)
 680                                         warnx("ignoring -a after %s",
 681                                             argv[*argi - 1]);
 682                                 else
 683                                         warnx("ignoring initial -a");
 684                         }
 685                         needterm = 1;
 686                         ++*argi;
 687                         continue;
 688                 }
 689                 if (needterm == 0)
 690                         break;
 691                 if (child == NULL) {
 692                         child = exprterm(search, argc, argv, argi);
 693                         if (child != NULL)
 694                                 needterm = 0;
 695                         continue;
 696                 }
 697                 needterm = 0;
 698                 if (parent == NULL) {
 699                         parent = mandoc_calloc(1, sizeof(*parent));
 700                         parent->type = EXPR_AND;
 701                         parent->next = NULL;
 702                         parent->child = child;
 703                 }
 704                 child->next = exprterm(search, argc, argv, argi);
 705                 if (child->next != NULL) {
 706                         child = child->next;
 707                         needterm = 0;
 708                 }
 709         }
 710         if (needterm && *argi)
 711                 warnx("ignoring trailing %s", argv[*argi - 1]);
 712         return parent == NULL ? child : parent;
 713 }
 714
 715 static struct expr *
 716 exprterm(const struct mansearch *search, int argc, char *argv[], int *argi)
 717 {
 718         char             errbuf[BUFSIZ];
 719         struct expr     *e;
 720         char            *key, *val;
 721         uint64_t         iterbit;
 722         int              cs, i, irc;
 723
 724         if (strcmp("(", argv[*argi]) == 0) {
 725                 ++*argi;
 726                 e = exprcomp(search, argc, argv, argi);
 727                 if (*argi < argc) {
 728                         assert(strcmp(")", argv[*argi]) == 0);
 729                         ++*argi;
 730                 } else
 731                         warnx("unclosed parenthesis");
 732                 return e;
 733         }
 734
 735         if (strcmp("-i", argv[*argi]) == 0 && *argi + 1 < argc) {
 736                 cs = 0;
 737                 ++*argi;
 738         } else
 739                 cs = 1;
 740
 741         e = mandoc_calloc(1, sizeof(*e));
 742         e->type = EXPR_TERM;
 743         e->bits = 0;
 744         e->next = NULL;
 745         e->child = NULL;
 746
 747         if (search->argmode == ARG_NAME) {
 748                 e->bits = TYPE_Nm;
 749                 e->match.type = DBM_EXACT;
 750                 e->match.str = argv[(*argi)++];
 751                 return e;
 752         }
 753
 754         /*
 755          * Separate macro keys from search string.
 756          * If needed, request regular expression handling.
 757          */
 758
 759         if (search->argmode == ARG_WORD) {
 760                 e->bits = TYPE_Nm;
 761                 e->match.type = DBM_REGEX;
 762 #if HAVE_REWB_BSD
 763                 mandoc_asprintf(&val, "[[:<:]]%s[[:>:]]", argv[*argi]);
 764 #elif HAVE_REWB_SYSV
 765                 mandoc_asprintf(&val, "\\<%s\\>", argv[*argi]);
 766 #else
 767                 mandoc_asprintf(&val,
 768                     "(^|[^a-zA-Z01-9_])%s([^a-zA-Z01-9_]|$)", argv[*argi]);
 769 #endif
 770                 cs = 0;
 771         } else if ((val = strpbrk(argv[*argi], "=~")) == NULL) {
 772                 e->bits = TYPE_Nm | TYPE_Nd;
 773                 e->match.type = DBM_REGEX;
 774                 val = argv[*argi];
 775                 cs = 0;
 776         } else {
 777                 if (val == argv[*argi])
 778                         e->bits = TYPE_Nm | TYPE_Nd;
 779                 if (*val == '=') {
 780                         e->match.type = DBM_SUB;
 781                         e->match.str = val + 1;
 782                 } else
 783                         e->match.type = DBM_REGEX;
 784                 *val++ = '\0';
 785                 if (strstr(argv[*argi], "arch") != NULL)
 786                         cs = 0;
 787         }
 788
 789         /* Compile regular expressions. */
 790
 791         if (e->match.type == DBM_REGEX) {
 792                 e->match.re = mandoc_malloc(sizeof(*e->match.re));
 793                 irc = regcomp(e->match.re, val,
 794                     REG_EXTENDED | REG_NOSUB | (cs ? 0 : REG_ICASE));
 795                 if (irc) {
 796                         regerror(irc, e->match.re, errbuf, sizeof(errbuf));
 797                         warnx("regcomp /%s/: %s", val, errbuf);
 798                 }
 799                 if (search->argmode == ARG_WORD)
 800                         free(val);
 801                 if (irc) {
 802                         free(e->match.re);
 803                         free(e);
 804                         ++*argi;
 805                         return NULL;
 806                 }
 807         }
 808
 809         if (e->bits) {
 810                 ++*argi;
 811                 return e;
 812         }
 813
 814         /*
 815          * Parse out all possible fields.
 816          * If the field doesn't resolve, bail.
 817          */
 818
 819         while (NULL != (key = strsep(&argv[*argi], ","))) {
 820                 if ('\0' == *key)
 821                         continue;
 822                 for (i = 0, iterbit = 1; i < KEY_MAX; i++, iterbit <<= 1) {
 823                         if (0 == strcasecmp(key, mansearch_keynames[i])) {
 824                                 e->bits |= iterbit;
 825                                 break;
 826                         }
 827                 }
 828                 if (i == KEY_MAX) {
 829                         if (strcasecmp(key, "any"))
 830                                 warnx("treating unknown key "
 831                                     "\"%s\" as \"any\"", key);
 832                         e->bits |= ~0ULL;
 833                 }
 834         }
 835
 836         ++*argi;
 837         return e;
 838 }
 839
 840 static void
 841 exprfree(struct expr *e)
 842 {
 843         if (e->next != NULL)
 844                 exprfree(e->next);
 845         if (e->child != NULL)
 846                 exprfree(e->child);
 847         free(e);
 848 }