mansearch.c

   1 /*      $Id: mansearch.c,v 1.26 2014/04/09 21:50:08 schwarze Exp $ */
   2 /*
   3  * Copyright (c) 2012 Kristaps Dzonsons <kristaps@bsd.lv>
   4  * Copyright (c) 2013, 2014 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 AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR 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 #ifdef HAVE_CONFIG_H
  19 #include "config.h"
  20 #endif
  21
  22 #include <assert.h>
  23 #include <fcntl.h>
  24 #include <getopt.h>
  25 #include <limits.h>
  26 #include <regex.h>
  27 #include <stdio.h>
  28 #include <stdint.h>
  29 #include <stddef.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32 #include <unistd.h>
  33
  34 #ifdef HAVE_OHASH
  35 #include <ohash.h>
  36 #else
  37 #include "compat_ohash.h"
  38 #endif
  39 #include <sqlite3.h>
  40
  41 #include "mandoc.h"
  42 #include "mandoc_aux.h"
  43 #include "manpath.h"
  44 #include "mansearch.h"
  45
  46 extern int mansearch_keymax;
  47 extern const char *const mansearch_keynames[];
  48
  49 #define SQL_BIND_TEXT(_db, _s, _i, _v) \
  50         do { if (SQLITE_OK != sqlite3_bind_text \
  51                 ((_s), (_i)++, (_v), -1, SQLITE_STATIC)) \
  52                 fprintf(stderr, "%s\n", sqlite3_errmsg((_db))); \
  53         } while (0)
  54 #define SQL_BIND_INT64(_db, _s, _i, _v) \
  55         do { if (SQLITE_OK != sqlite3_bind_int64 \
  56                 ((_s), (_i)++, (_v))) \
  57                 fprintf(stderr, "%s\n", sqlite3_errmsg((_db))); \
  58         } while (0)
  59 #define SQL_BIND_BLOB(_db, _s, _i, _v) \
  60         do { if (SQLITE_OK != sqlite3_bind_blob \
  61                 ((_s), (_i)++, (&_v), sizeof(_v), SQLITE_STATIC)) \
  62                 fprintf(stderr, "%s\n", sqlite3_errmsg((_db))); \
  63         } while (0)
  64
  65 struct  expr {
  66         uint64_t         bits;    /* type-mask */
  67         const char      *substr;  /* to search for, if applicable */
  68         regex_t          regexp;  /* compiled regexp, if applicable */
  69         int              open;    /* opening parentheses before */
  70         int              and;     /* logical AND before */
  71         int              close;   /* closing parentheses after */
  72         struct expr     *next;    /* next in sequence */
  73 };
  74
  75 struct  match {
  76         uint64_t         id; /* identifier in database */
  77         char            *desc; /* manual page description */
  78         int              form; /* 0 == catpage */
  79 };
  80
  81 static  void             buildnames(struct manpage *, sqlite3 *,
  82                                 sqlite3_stmt *, uint64_t,
  83                                 const char *, int form);
  84 static  char            *buildoutput(sqlite3 *, sqlite3_stmt *,
  85                                  uint64_t, uint64_t);
  86 static  void            *hash_alloc(size_t, void *);
  87 static  void             hash_free(void *, size_t, void *);
  88 static  void            *hash_halloc(size_t, void *);
  89 static  struct expr     *exprcomp(const struct mansearch *,
  90                                 int, char *[]);
  91 static  void             exprfree(struct expr *);
  92 static  struct expr     *exprspec(struct expr *, uint64_t,
  93                                  const char *, const char *);
  94 static  struct expr     *exprterm(const struct mansearch *, char *, int);
  95 static  void             sql_append(char **sql, size_t *sz,
  96                                 const char *newstr, int count);
  97 static  void             sql_match(sqlite3_context *context,
  98                                 int argc, sqlite3_value **argv);
  99 static  void             sql_regexp(sqlite3_context *context,
 100                                 int argc, sqlite3_value **argv);
 101 static  char            *sql_statement(const struct expr *);
 102
 103 int
 104 mansearch(const struct mansearch *search,
 105                 const struct manpaths *paths,
 106                 int argc, char *argv[],
 107                 const char *outkey,
 108                 struct manpage **res, size_t *sz)
 109 {
 110         int              fd, rc, c, indexbit;
 111         int64_t          id;
 112         uint64_t         outbit, iterbit;
 113         char             buf[PATH_MAX];
 114         char            *sql;
 115         struct manpage  *mpage;
 116         struct expr     *e, *ep;
 117         sqlite3         *db;
 118         sqlite3_stmt    *s, *s2;
 119         struct match    *mp;
 120         struct ohash_info info;
 121         struct ohash     htab;
 122         unsigned int     idx;
 123         size_t           i, j, cur, maxres;
 124
 125         memset(&info, 0, sizeof(struct ohash_info));
 126
 127         info.halloc = hash_halloc;
 128         info.alloc = hash_alloc;
 129         info.hfree = hash_free;
 130         info.key_offset = offsetof(struct match, id);
 131
 132         *sz = cur = maxres = 0;
 133         sql = NULL;
 134         *res = NULL;
 135         fd = -1;
 136         e = NULL;
 137         rc = 0;
 138
 139         if (0 == argc)
 140                 goto out;
 141         if (NULL == (e = exprcomp(search, argc, argv)))
 142                 goto out;
 143
 144         outbit = 0;
 145         if (NULL != outkey) {
 146                 for (indexbit = 0, iterbit = 1;
 147                      indexbit < mansearch_keymax;
 148                      indexbit++, iterbit <<= 1) {
 149                         if (0 == strcasecmp(outkey,
 150                             mansearch_keynames[indexbit])) {
 151                                 outbit = iterbit;
 152                                 break;
 153                         }
 154                 }
 155         }
 156
 157         /*
 158          * Save a descriptor to the current working directory.
 159          * Since pathnames in the "paths" variable might be relative,
 160          * and we'll be chdir()ing into them, we need to keep a handle
 161          * on our current directory from which to start the chdir().
 162          */
 163
 164         if (NULL == getcwd(buf, PATH_MAX)) {
 165                 perror(NULL);
 166                 goto out;
 167         } else if (-1 == (fd = open(buf, O_RDONLY, 0))) {
 168                 perror(buf);
 169                 goto out;
 170         }
 171
 172         sql = sql_statement(e);
 173
 174         /*
 175          * Loop over the directories (containing databases) for us to
 176          * search.
 177          * Don't let missing/bad databases/directories phase us.
 178          * In each, try to open the resident database and, if it opens,
 179          * scan it for our match expression.
 180          */
 181
 182         for (i = 0; i < paths->sz; i++) {
 183                 if (-1 == fchdir(fd)) {
 184                         perror(buf);
 185                         free(*res);
 186                         break;
 187                 } else if (-1 == chdir(paths->paths[i])) {
 188                         perror(paths->paths[i]);
 189                         continue;
 190                 }
 191
 192                 c =  sqlite3_open_v2
 193                         (MANDOC_DB, &db,
 194                          SQLITE_OPEN_READONLY, NULL);
 195
 196                 if (SQLITE_OK != c) {
 197                         perror(MANDOC_DB);
 198                         sqlite3_close(db);
 199                         continue;
 200                 }
 201
 202                 /*
 203                  * Define the SQL functions for substring
 204                  * and regular expression matching.
 205                  */
 206
 207                 c = sqlite3_create_function(db, "match", 2,
 208                     SQLITE_ANY, NULL, sql_match, NULL, NULL);
 209                 assert(SQLITE_OK == c);
 210                 c = sqlite3_create_function(db, "regexp", 2,
 211                     SQLITE_ANY, NULL, sql_regexp, NULL, NULL);
 212                 assert(SQLITE_OK == c);
 213
 214                 j = 1;
 215                 c = sqlite3_prepare_v2(db, sql, -1, &s, NULL);
 216                 if (SQLITE_OK != c)
 217                         fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 218
 219                 for (ep = e; NULL != ep; ep = ep->next) {
 220                         if (NULL == ep->substr) {
 221                                 SQL_BIND_BLOB(db, s, j, ep->regexp);
 222                         } else
 223                                 SQL_BIND_TEXT(db, s, j, ep->substr);
 224                         if (0 == (TYPE_Nd & ep->bits))
 225                                 SQL_BIND_INT64(db, s, j, ep->bits);
 226                 }
 227
 228                 memset(&htab, 0, sizeof(struct ohash));
 229                 ohash_init(&htab, 4, &info);
 230
 231                 /*
 232                  * Hash each entry on its [unique] document identifier.
 233                  * This is a uint64_t.
 234                  * Instead of using a hash function, simply convert the
 235                  * uint64_t to a uint32_t, the hash value's type.
 236                  * This gives good performance and preserves the
 237                  * distribution of buckets in the table.
 238                  */
 239                 while (SQLITE_ROW == (c = sqlite3_step(s))) {
 240                         id = sqlite3_column_int64(s, 2);
 241                         idx = ohash_lookup_memory
 242                                 (&htab, (char *)&id,
 243                                  sizeof(uint64_t), (uint32_t)id);
 244
 245                         if (NULL != ohash_find(&htab, idx))
 246                                 continue;
 247
 248                         mp = mandoc_calloc(1, sizeof(struct match));
 249                         mp->id = id;
 250                         mp->form = sqlite3_column_int(s, 1);
 251                         if (TYPE_Nd == outbit)
 252                                 mp->desc = mandoc_strdup(
 253                                     sqlite3_column_text(s, 0));
 254                         ohash_insert(&htab, idx, mp);
 255                 }
 256
 257                 if (SQLITE_DONE != c)
 258                         fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 259
 260                 sqlite3_finalize(s);
 261
 262                 c = sqlite3_prepare_v2(db,
 263                     "SELECT * FROM mlinks WHERE pageid=?"
 264                     " ORDER BY sec, arch, name",
 265                     -1, &s, NULL);
 266                 if (SQLITE_OK != c)
 267                         fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 268
 269                 c = sqlite3_prepare_v2(db,
 270                     "SELECT * FROM keys WHERE pageid=? AND bits & ?",
 271                     -1, &s2, NULL);
 272                 if (SQLITE_OK != c)
 273                         fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 274
 275                 for (mp = ohash_first(&htab, &idx);
 276                                 NULL != mp;
 277                                 mp = ohash_next(&htab, &idx)) {
 278                         if (cur + 1 > maxres) {
 279                                 maxres += 1024;
 280                                 *res = mandoc_realloc
 281                                         (*res, maxres * sizeof(struct manpage));
 282                         }
 283                         mpage = *res + cur;
 284                         mpage->form = mp->form;
 285                         buildnames(mpage, db, s, mp->id,
 286                             paths->paths[i], mp->form);
 287                         mpage->output = TYPE_Nd & outbit ?
 288                             mp->desc : outbit ?
 289                             buildoutput(db, s2, mp->id, outbit) : NULL;
 290
 291                         free(mp);
 292                         cur++;
 293                 }
 294
 295                 sqlite3_finalize(s);
 296                 sqlite3_finalize(s2);
 297                 sqlite3_close(db);
 298                 ohash_delete(&htab);
 299         }
 300         rc = 1;
 301 out:
 302         exprfree(e);
 303         if (-1 != fd)
 304                 close(fd);
 305         free(sql);
 306         *sz = cur;
 307         return(rc);
 308 }
 309
 310 static void
 311 buildnames(struct manpage *mpage, sqlite3 *db, sqlite3_stmt *s,
 312                 uint64_t id, const char *path, int form)
 313 {
 314         char            *newnames, *prevsec, *prevarch;
 315         const char      *oldnames, *sep1, *name, *sec, *sep2, *arch, *fsec;
 316         size_t           i;
 317         int              c;
 318
 319         mpage->file = NULL;
 320         mpage->names = NULL;
 321         prevsec = prevarch = NULL;
 322         i = 1;
 323         SQL_BIND_INT64(db, s, i, id);
 324         while (SQLITE_ROW == (c = sqlite3_step(s))) {
 325
 326                 /* Decide whether we already have some names. */
 327
 328                 if (NULL == mpage->names) {
 329                         oldnames = "";
 330                         sep1 = "";
 331                 } else {
 332                         oldnames = mpage->names;
 333                         sep1 = ", ";
 334                 }
 335
 336                 /* Fetch the next name. */
 337
 338                 sec = sqlite3_column_text(s, 0);
 339                 arch = sqlite3_column_text(s, 1);
 340                 name = sqlite3_column_text(s, 2);
 341
 342                 /* If the section changed, append the old one. */
 343
 344                 if (NULL != prevsec &&
 345                     (strcmp(sec, prevsec) ||
 346                      strcmp(arch, prevarch))) {
 347                         sep2 = '\0' == *prevarch ? "" : "/";
 348                         mandoc_asprintf(&newnames, "%s(%s%s%s)",
 349                             oldnames, prevsec, sep2, prevarch);
 350                         free(mpage->names);
 351                         oldnames = mpage->names = newnames;
 352                         free(prevsec);
 353                         free(prevarch);
 354                         prevsec = prevarch = NULL;
 355                 }
 356
 357                 /* Save the new section, to append it later. */
 358
 359                 if (NULL == prevsec) {
 360                         prevsec = mandoc_strdup(sec);
 361                         prevarch = mandoc_strdup(arch);
 362                 }
 363
 364                 /* Append the new name. */
 365
 366                 mandoc_asprintf(&newnames, "%s%s%s",
 367                     oldnames, sep1, name);
 368                 free(mpage->names);
 369                 mpage->names = newnames;
 370
 371                 /* Also save the first file name encountered. */
 372
 373                 if (NULL != mpage->file)
 374                         continue;
 375
 376                 if (form) {
 377                         sep1 = "man";
 378                         fsec = sec;
 379                 } else {
 380                         sep1 = "cat";
 381                         fsec = "0";
 382                 }
 383                 sep2 = '\0' == *arch ? "" : "/";
 384                 mandoc_asprintf(&mpage->file, "%s/%s%s%s%s/%s.%s",
 385                     path, sep1, sec, sep2, arch, name, fsec);
 386         }
 387         if (SQLITE_DONE != c)
 388                 fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 389         sqlite3_reset(s);
 390
 391         /* Append one final section to the names. */
 392
 393         if (NULL != prevsec) {
 394                 sep2 = '\0' == *prevarch ? "" : "/";
 395                 mandoc_asprintf(&newnames, "%s(%s%s%s)",
 396                     mpage->names, prevsec, sep2, prevarch);
 397                 free(mpage->names);
 398                 mpage->names = newnames;
 399                 free(prevsec);
 400                 free(prevarch);
 401         }
 402 }
 403
 404 static char *
 405 buildoutput(sqlite3 *db, sqlite3_stmt *s, uint64_t id, uint64_t outbit)
 406 {
 407         char            *output, *newoutput;
 408         const char      *oldoutput, *sep1, *data;
 409         size_t           i;
 410         int              c;
 411
 412         output = NULL;
 413         i = 1;
 414         SQL_BIND_INT64(db, s, i, id);
 415         SQL_BIND_INT64(db, s, i, outbit);
 416         while (SQLITE_ROW == (c = sqlite3_step(s))) {
 417                 if (NULL == output) {
 418                         oldoutput = "";
 419                         sep1 = "";
 420                 } else {
 421                         oldoutput = output;
 422                         sep1 = " # ";
 423                 }
 424                 data = sqlite3_column_text(s, 1);
 425                 mandoc_asprintf(&newoutput, "%s%s%s",
 426                     oldoutput, sep1, data);
 427                 free(output);
 428                 output = newoutput;
 429         }
 430         if (SQLITE_DONE != c)
 431                 fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 432         sqlite3_reset(s);
 433         return(output);
 434 }
 435
 436 /*
 437  * Implement substring match as an application-defined SQL function.
 438  * Using the SQL LIKE or GLOB operators instead would be a bad idea
 439  * because that would require escaping metacharacters in the string
 440  * being searched for.
 441  */
 442 static void
 443 sql_match(sqlite3_context *context, int argc, sqlite3_value **argv)
 444 {
 445
 446         assert(2 == argc);
 447         sqlite3_result_int(context, NULL != strcasestr(
 448             (const char *)sqlite3_value_text(argv[1]),
 449             (const char *)sqlite3_value_text(argv[0])));
 450 }
 451
 452 /*
 453  * Implement regular expression match
 454  * as an application-defined SQL function.
 455  */
 456 static void
 457 sql_regexp(sqlite3_context *context, int argc, sqlite3_value **argv)
 458 {
 459
 460         assert(2 == argc);
 461         sqlite3_result_int(context, !regexec(
 462             (regex_t *)sqlite3_value_blob(argv[0]),
 463             (const char *)sqlite3_value_text(argv[1]),
 464             0, NULL, 0));
 465 }
 466
 467 static void
 468 sql_append(char **sql, size_t *sz, const char *newstr, int count)
 469 {
 470         size_t           newsz;
 471
 472         newsz = 1 < count ? (size_t)count : strlen(newstr);
 473         *sql = mandoc_realloc(*sql, *sz + newsz + 1);
 474         if (1 < count)
 475                 memset(*sql + *sz, *newstr, (size_t)count);
 476         else
 477                 memcpy(*sql + *sz, newstr, newsz);
 478         *sz += newsz;
 479         (*sql)[*sz] = '\0';
 480 }
 481
 482 /*
 483  * Prepare the search SQL statement.
 484  */
 485 static char *
 486 sql_statement(const struct expr *e)
 487 {
 488         char            *sql;
 489         size_t           sz;
 490         int              needop;
 491
 492         sql = mandoc_strdup("SELECT * FROM mpages WHERE ");
 493         sz = strlen(sql);
 494
 495         for (needop = 0; NULL != e; e = e->next) {
 496                 if (e->and)
 497                         sql_append(&sql, &sz, " AND ", 1);
 498                 else if (needop)
 499                         sql_append(&sql, &sz, " OR ", 1);
 500                 if (e->open)
 501                         sql_append(&sql, &sz, "(", e->open);
 502                 sql_append(&sql, &sz,
 503                     TYPE_Nd & e->bits
 504                     ? (NULL == e->substr
 505                         ? "desc REGEXP ?"
 506                         : "desc MATCH ?")
 507                     : (NULL == e->substr
 508                         ? "id IN (SELECT pageid FROM keys "
 509                           "WHERE key REGEXP ? AND bits & ?)"
 510                         : "id IN (SELECT pageid FROM keys "
 511                           "WHERE key MATCH ? AND bits & ?)"), 1);
 512                 if (e->close)
 513                         sql_append(&sql, &sz, ")", e->close);
 514                 needop = 1;
 515         }
 516
 517         return(sql);
 518 }
 519
 520 /*
 521  * Compile a set of string tokens into an expression.
 522  * Tokens in "argv" are assumed to be individual expression atoms (e.g.,
 523  * "(", "foo=bar", etc.).
 524  */
 525 static struct expr *
 526 exprcomp(const struct mansearch *search, int argc, char *argv[])
 527 {
 528         int              i, toopen, logic, igncase, toclose;
 529         struct expr     *first, *next, *cur;
 530
 531         first = cur = NULL;
 532         logic = igncase = toclose = 0;
 533         toopen = 1;
 534
 535         for (i = 0; i < argc; i++) {
 536                 if (0 == strcmp("(", argv[i])) {
 537                         if (igncase)
 538                                 goto fail;
 539                         toopen++;
 540                         toclose++;
 541                         continue;
 542                 } else if (0 == strcmp(")", argv[i])) {
 543                         if (toopen || logic || igncase || NULL == cur)
 544                                 goto fail;
 545                         cur->close++;
 546                         if (0 > --toclose)
 547                                 goto fail;
 548                         continue;
 549                 } else if (0 == strcmp("-a", argv[i])) {
 550                         if (toopen || logic || igncase || NULL == cur)
 551                                 goto fail;
 552                         logic = 1;
 553                         continue;
 554                 } else if (0 == strcmp("-o", argv[i])) {
 555                         if (toopen || logic || igncase || NULL == cur)
 556                                 goto fail;
 557                         logic = 2;
 558                         continue;
 559                 } else if (0 == strcmp("-i", argv[i])) {
 560                         if (igncase)
 561                                 goto fail;
 562                         igncase = 1;
 563                         continue;
 564                 }
 565                 next = exprterm(search, argv[i], !igncase);
 566                 if (NULL == next)
 567                         goto fail;
 568                 if (NULL == first)
 569                         first = next;
 570                 else
 571                         cur->next = next;
 572
 573                 /*
 574                  * Searching for descriptions must be split out
 575                  * because they are stored in the mpages table,
 576                  * not in the keys table.
 577                  */
 578
 579                 if (TYPE_Nd & next->bits && ~TYPE_Nd & next->bits) {
 580                         cur = mandoc_calloc(1, sizeof(struct expr));
 581                         memcpy(cur, next, sizeof(struct expr));
 582                         next->open = 1;
 583                         next->bits = TYPE_Nd;
 584                         next->next = cur;
 585                         cur->bits &= ~TYPE_Nd;
 586                         cur->close = 1;
 587                 } else
 588                         cur = next;
 589                 next->and = (1 == logic);
 590                 next->open += toopen;
 591                 toopen = logic = igncase = 0;
 592         }
 593         if (toopen || logic || igncase || toclose)
 594                 goto fail;
 595
 596         cur->close++;
 597         cur = exprspec(cur, TYPE_arch, search->arch, "^(%s|any)$");
 598         exprspec(cur, TYPE_sec, search->sec, "^%s$");
 599
 600         return(first);
 601
 602 fail:
 603         if (NULL != first)
 604                 exprfree(first);
 605         return(NULL);
 606 }
 607
 608 static struct expr *
 609 exprspec(struct expr *cur, uint64_t key, const char *value,
 610                 const char *format)
 611 {
 612         char     errbuf[BUFSIZ];
 613         char    *cp;
 614         int      irc;
 615
 616         if (NULL == value)
 617                 return(cur);
 618
 619         mandoc_asprintf(&cp, format, value);
 620         cur->next = mandoc_calloc(1, sizeof(struct expr));
 621         cur = cur->next;
 622         cur->and = 1;
 623         cur->bits = key;
 624         if (0 != (irc = regcomp(&cur->regexp, cp,
 625             REG_EXTENDED | REG_NOSUB | REG_ICASE))) {
 626                 regerror(irc, &cur->regexp, errbuf, sizeof(errbuf));
 627                 fprintf(stderr, "regcomp: %s\n", errbuf);
 628                 cur->substr = value;
 629         }
 630         free(cp);
 631         return(cur);
 632 }
 633
 634 static struct expr *
 635 exprterm(const struct mansearch *search, char *buf, int cs)
 636 {
 637         char             errbuf[BUFSIZ];
 638         struct expr     *e;
 639         char            *key, *v;
 640         uint64_t         iterbit;
 641         int              i, irc;
 642
 643         if ('\0' == *buf)
 644                 return(NULL);
 645
 646         e = mandoc_calloc(1, sizeof(struct expr));
 647
 648         /*"whatis" mode uses an opaque string and default fields. */
 649
 650         if (MANSEARCH_WHATIS & search->flags) {
 651                 e->substr = buf;
 652                 e->bits = search->deftype;
 653                 return(e);
 654         }
 655
 656         /*
 657          * If no =~ is specified, search with equality over names and
 658          * descriptions.
 659          * If =~ begins the phrase, use name and description fields.
 660          */
 661
 662         if (NULL == (v = strpbrk(buf, "=~"))) {
 663                 e->substr = buf;
 664                 e->bits = search->deftype;
 665                 return(e);
 666         } else if (v == buf)
 667                 e->bits = search->deftype;
 668
 669         if ('~' == *v++) {
 670                 if (NULL != strstr(buf, "arch"))
 671                         cs = 0;
 672                 if (0 != (irc = regcomp(&e->regexp, v,
 673                     REG_EXTENDED | REG_NOSUB | (cs ? 0 : REG_ICASE)))) {
 674                         regerror(irc, &e->regexp, errbuf, sizeof(errbuf));
 675                         fprintf(stderr, "regcomp: %s\n", errbuf);
 676                         free(e);
 677                         return(NULL);
 678                 }
 679         } else
 680                 e->substr = v;
 681         v[-1] = '\0';
 682
 683         /*
 684          * Parse out all possible fields.
 685          * If the field doesn't resolve, bail.
 686          */
 687
 688         while (NULL != (key = strsep(&buf, ","))) {
 689                 if ('\0' == *key)
 690                         continue;
 691                 for (i = 0, iterbit = 1;
 692                      i < mansearch_keymax;
 693                      i++, iterbit <<= 1) {
 694                         if (0 == strcasecmp(key,
 695                             mansearch_keynames[i])) {
 696                                 e->bits |= iterbit;
 697                                 break;
 698                         }
 699                 }
 700                 if (i == mansearch_keymax) {
 701                         if (strcasecmp(key, "any")) {
 702                                 free(e);
 703                                 return(NULL);
 704                         }
 705                         e->bits |= ~0ULL;
 706                 }
 707         }
 708
 709         return(e);
 710 }
 711
 712 static void
 713 exprfree(struct expr *p)
 714 {
 715         struct expr     *pp;
 716
 717         while (NULL != p) {
 718                 pp = p->next;
 719                 free(p);
 720                 p = pp;
 721         }
 722 }
 723
 724 static void *
 725 hash_halloc(size_t sz, void *arg)
 726 {
 727
 728         return(mandoc_calloc(sz, 1));
 729 }
 730
 731 static void *
 732 hash_alloc(size_t sz, void *arg)
 733 {
 734
 735         return(mandoc_malloc(sz));
 736 }
 737
 738 static void
 739 hash_free(void *p, size_t sz, void *arg)
 740 {
 741
 742         free(p);
 743 }