mansearch.c

   1 /*      $Id: mansearch.c,v 1.22 2014/03/17 16:31:44 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 "manpath.h"
  43 #include "mansearch.h"
  44
  45 extern int mansearch_keymax;
  46 extern const char *const mansearch_keynames[];
  47
  48 #define SQL_BIND_TEXT(_db, _s, _i, _v) \
  49         do { if (SQLITE_OK != sqlite3_bind_text \
  50                 ((_s), (_i)++, (_v), -1, SQLITE_STATIC)) \
  51                 fprintf(stderr, "%s\n", sqlite3_errmsg((_db))); \
  52         } while (0)
  53 #define SQL_BIND_INT64(_db, _s, _i, _v) \
  54         do { if (SQLITE_OK != sqlite3_bind_int64 \
  55                 ((_s), (_i)++, (_v))) \
  56                 fprintf(stderr, "%s\n", sqlite3_errmsg((_db))); \
  57         } while (0)
  58 #define SQL_BIND_BLOB(_db, _s, _i, _v) \
  59         do { if (SQLITE_OK != sqlite3_bind_blob \
  60                 ((_s), (_i)++, (&_v), sizeof(_v), SQLITE_STATIC)) \
  61                 fprintf(stderr, "%s\n", sqlite3_errmsg((_db))); \
  62         } while (0)
  63
  64 struct  expr {
  65         uint64_t         bits;    /* type-mask */
  66         const char      *substr;  /* to search for, if applicable */
  67         regex_t          regexp;  /* compiled regexp, if applicable */
  68         int              open;    /* opening parentheses before */
  69         int              and;     /* logical AND before */
  70         int              close;   /* closing parentheses after */
  71         struct expr     *next;    /* next in sequence */
  72 };
  73
  74 struct  match {
  75         uint64_t         id; /* identifier in database */
  76         int              form; /* 0 == catpage */
  77 };
  78
  79 static  void             buildnames(struct manpage *, sqlite3 *,
  80                                 sqlite3_stmt *, uint64_t,
  81                                 const char *, int form);
  82 static  char            *buildoutput(sqlite3 *, sqlite3_stmt *,
  83                                  uint64_t, uint64_t);
  84 static  void            *hash_alloc(size_t, void *);
  85 static  void             hash_free(void *, size_t, void *);
  86 static  void            *hash_halloc(size_t, void *);
  87 static  struct expr     *exprcomp(const struct mansearch *,
  88                                 int, char *[]);
  89 static  void             exprfree(struct expr *);
  90 static  struct expr     *exprspec(struct expr *, uint64_t,
  91                                  const char *, const char *);
  92 static  struct expr     *exprterm(const struct mansearch *, char *, int);
  93 static  void             sql_append(char **sql, size_t *sz,
  94                                 const char *newstr, int count);
  95 static  void             sql_match(sqlite3_context *context,
  96                                 int argc, sqlite3_value **argv);
  97 static  void             sql_regexp(sqlite3_context *context,
  98                                 int argc, sqlite3_value **argv);
  99 static  char            *sql_statement(const struct expr *);
 100
 101 int
 102 mansearch(const struct mansearch *search,
 103                 const struct manpaths *paths,
 104                 int argc, char *argv[],
 105                 const char *outkey,
 106                 struct manpage **res, size_t *sz)
 107 {
 108         int              fd, rc, c, indexbit;
 109         int64_t          id;
 110         uint64_t         outbit, iterbit;
 111         char             buf[PATH_MAX];
 112         char            *sql;
 113         struct manpage  *mpage;
 114         struct expr     *e, *ep;
 115         sqlite3         *db;
 116         sqlite3_stmt    *s, *s2;
 117         struct match    *mp;
 118         struct ohash_info info;
 119         struct ohash     htab;
 120         unsigned int     idx;
 121         size_t           i, j, cur, maxres;
 122
 123         memset(&info, 0, sizeof(struct ohash_info));
 124
 125         info.halloc = hash_halloc;
 126         info.alloc = hash_alloc;
 127         info.hfree = hash_free;
 128         info.key_offset = offsetof(struct match, id);
 129
 130         *sz = cur = maxres = 0;
 131         sql = NULL;
 132         *res = NULL;
 133         fd = -1;
 134         e = NULL;
 135         rc = 0;
 136
 137         if (0 == argc)
 138                 goto out;
 139         if (NULL == (e = exprcomp(search, argc, argv)))
 140                 goto out;
 141
 142         outbit = 0;
 143         if (NULL != outkey) {
 144                 for (indexbit = 0, iterbit = 1;
 145                      indexbit < mansearch_keymax;
 146                      indexbit++, iterbit <<= 1) {
 147                         if (0 == strcasecmp(outkey,
 148                             mansearch_keynames[indexbit])) {
 149                                 outbit = iterbit;
 150                                 break;
 151                         }
 152                 }
 153         }
 154
 155         /*
 156          * Save a descriptor to the current working directory.
 157          * Since pathnames in the "paths" variable might be relative,
 158          * and we'll be chdir()ing into them, we need to keep a handle
 159          * on our current directory from which to start the chdir().
 160          */
 161
 162         if (NULL == getcwd(buf, PATH_MAX)) {
 163                 perror(NULL);
 164                 goto out;
 165         } else if (-1 == (fd = open(buf, O_RDONLY, 0))) {
 166                 perror(buf);
 167                 goto out;
 168         }
 169
 170         sql = sql_statement(e);
 171
 172         /*
 173          * Loop over the directories (containing databases) for us to
 174          * search.
 175          * Don't let missing/bad databases/directories phase us.
 176          * In each, try to open the resident database and, if it opens,
 177          * scan it for our match expression.
 178          */
 179
 180         for (i = 0; i < paths->sz; i++) {
 181                 if (-1 == fchdir(fd)) {
 182                         perror(buf);
 183                         free(*res);
 184                         break;
 185                 } else if (-1 == chdir(paths->paths[i])) {
 186                         perror(paths->paths[i]);
 187                         continue;
 188                 }
 189
 190                 c =  sqlite3_open_v2
 191                         (MANDOC_DB, &db,
 192                          SQLITE_OPEN_READONLY, NULL);
 193
 194                 if (SQLITE_OK != c) {
 195                         perror(MANDOC_DB);
 196                         sqlite3_close(db);
 197                         continue;
 198                 }
 199
 200                 /*
 201                  * Define the SQL functions for substring
 202                  * and regular expression matching.
 203                  */
 204
 205                 c = sqlite3_create_function(db, "match", 2,
 206                     SQLITE_ANY, NULL, sql_match, NULL, NULL);
 207                 assert(SQLITE_OK == c);
 208                 c = sqlite3_create_function(db, "regexp", 2,
 209                     SQLITE_ANY, NULL, sql_regexp, NULL, NULL);
 210                 assert(SQLITE_OK == c);
 211
 212                 j = 1;
 213                 c = sqlite3_prepare_v2(db, sql, -1, &s, NULL);
 214                 if (SQLITE_OK != c)
 215                         fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 216
 217                 for (ep = e; NULL != ep; ep = ep->next) {
 218                         if (NULL == ep->substr) {
 219                                 SQL_BIND_BLOB(db, s, j, ep->regexp);
 220                         } else
 221                                 SQL_BIND_TEXT(db, s, j, ep->substr);
 222                         SQL_BIND_INT64(db, s, j, ep->bits);
 223                 }
 224
 225                 memset(&htab, 0, sizeof(struct ohash));
 226                 ohash_init(&htab, 4, &info);
 227
 228                 /*
 229                  * Hash each entry on its [unique] document identifier.
 230                  * This is a uint64_t.
 231                  * Instead of using a hash function, simply convert the
 232                  * uint64_t to a uint32_t, the hash value's type.
 233                  * This gives good performance and preserves the
 234                  * distribution of buckets in the table.
 235                  */
 236                 while (SQLITE_ROW == (c = sqlite3_step(s))) {
 237                         id = sqlite3_column_int64(s, 1);
 238                         idx = ohash_lookup_memory
 239                                 (&htab, (char *)&id,
 240                                  sizeof(uint64_t), (uint32_t)id);
 241
 242                         if (NULL != ohash_find(&htab, idx))
 243                                 continue;
 244
 245                         mp = mandoc_calloc(1, sizeof(struct match));
 246                         mp->id = id;
 247                         mp->form = sqlite3_column_int(s, 0);
 248                         ohash_insert(&htab, idx, mp);
 249                 }
 250
 251                 if (SQLITE_DONE != c)
 252                         fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 253
 254                 sqlite3_finalize(s);
 255
 256                 c = sqlite3_prepare_v2(db,
 257                     "SELECT * FROM mlinks WHERE pageid=?"
 258                     " ORDER BY sec, arch, name",
 259                     -1, &s, NULL);
 260                 if (SQLITE_OK != c)
 261                         fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 262
 263                 c = sqlite3_prepare_v2(db,
 264                     "SELECT * FROM keys WHERE pageid=? AND bits & ?",
 265                     -1, &s2, NULL);
 266                 if (SQLITE_OK != c)
 267                         fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 268
 269                 for (mp = ohash_first(&htab, &idx);
 270                                 NULL != mp;
 271                                 mp = ohash_next(&htab, &idx)) {
 272                         if (cur + 1 > maxres) {
 273                                 maxres += 1024;
 274                                 *res = mandoc_realloc
 275                                         (*res, maxres * sizeof(struct manpage));
 276                         }
 277                         mpage = *res + cur;
 278                         mpage->form = mp->form;
 279                         buildnames(mpage, db, s, mp->id,
 280                             paths->paths[i], mp->form);
 281                         mpage->output = outbit ?
 282                             buildoutput(db, s2, mp->id, outbit) : NULL;
 283
 284                         free(mp);
 285                         cur++;
 286                 }
 287
 288                 sqlite3_finalize(s);
 289                 sqlite3_finalize(s2);
 290                 sqlite3_close(db);
 291                 ohash_delete(&htab);
 292         }
 293         rc = 1;
 294 out:
 295         exprfree(e);
 296         if (-1 != fd)
 297                 close(fd);
 298         free(sql);
 299         *sz = cur;
 300         return(rc);
 301 }
 302
 303 static void
 304 buildnames(struct manpage *mpage, sqlite3 *db, sqlite3_stmt *s,
 305                 uint64_t id, const char *path, int form)
 306 {
 307         char            *newnames, *prevsec, *prevarch;
 308         const char      *oldnames, *sep1, *name, *sec, *sep2, *arch, *fsec;
 309         size_t           i;
 310         int              c;
 311
 312         mpage->names = NULL;
 313         prevsec = prevarch = NULL;
 314         i = 1;
 315         SQL_BIND_INT64(db, s, i, id);
 316         while (SQLITE_ROW == (c = sqlite3_step(s))) {
 317
 318                 /* Decide whether we already have some names. */
 319
 320                 if (NULL == mpage->names) {
 321                         oldnames = "";
 322                         sep1 = "";
 323                 } else {
 324                         oldnames = mpage->names;
 325                         sep1 = ", ";
 326                 }
 327
 328                 /* Fetch the next name. */
 329
 330                 sec = sqlite3_column_text(s, 0);
 331                 arch = sqlite3_column_text(s, 1);
 332                 name = sqlite3_column_text(s, 2);
 333
 334                 /* If the section changed, append the old one. */
 335
 336                 if (NULL != prevsec &&
 337                     (strcmp(sec, prevsec) ||
 338                      strcmp(arch, prevarch))) {
 339                         sep2 = '\0' == *prevarch ? "" : "/";
 340                         if (-1 == asprintf(&newnames, "%s(%s%s%s)",
 341                             oldnames, prevsec, sep2, prevarch)) {
 342                                 perror(0);
 343                                 exit((int)MANDOCLEVEL_SYSERR);
 344                         }
 345                         free(mpage->names);
 346                         oldnames = mpage->names = newnames;
 347                         free(prevsec);
 348                         free(prevarch);
 349                         prevsec = prevarch = NULL;
 350                 }
 351
 352                 /* Save the new section, to append it later. */
 353
 354                 if (NULL == prevsec) {
 355                         prevsec = mandoc_strdup(sec);
 356                         prevarch = mandoc_strdup(arch);
 357                 }
 358
 359                 /* Append the new name. */
 360
 361                 if (-1 == asprintf(&newnames, "%s%s%s",
 362                     oldnames, sep1, name)) {
 363                         perror(0);
 364                         exit((int)MANDOCLEVEL_SYSERR);
 365                 }
 366                 free(mpage->names);
 367                 mpage->names = newnames;
 368
 369                 /* Also save the first file name encountered. */
 370
 371                 if (NULL != mpage->file)
 372                         continue;
 373
 374                 if (form) {
 375                         sep1 = "man";
 376                         fsec = sec;
 377                 } else {
 378                         sep1 = "cat";
 379                         fsec = "0";
 380                 }
 381                 sep2 = '\0' == *arch ? "" : "/";
 382                 if (-1 == asprintf(&mpage->file, "%s/%s%s%s%s/%s.%s",
 383                     path, sep1, sec, sep2, arch, name, fsec)) {
 384                         perror(0);
 385                         exit((int)MANDOCLEVEL_SYSERR);
 386                 }
 387         }
 388         if (SQLITE_DONE != c)
 389                 fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 390         sqlite3_reset(s);
 391
 392         /* Append one final section to the names. */
 393
 394         if (NULL != prevsec) {
 395                 sep2 = '\0' == *prevarch ? "" : "/";
 396                 if (-1 == asprintf(&newnames, "%s(%s%s%s)",
 397                     mpage->names, prevsec, sep2, prevarch)) {
 398                         perror(0);
 399                         exit((int)MANDOCLEVEL_SYSERR);
 400                 }
 401                 free(mpage->names);
 402                 mpage->names = newnames;
 403                 free(prevsec);
 404                 free(prevarch);
 405         }
 406 }
 407
 408 static char *
 409 buildoutput(sqlite3 *db, sqlite3_stmt *s, uint64_t id, uint64_t outbit)
 410 {
 411         char            *output, *newoutput;
 412         const char      *oldoutput, *sep1, *data;
 413         size_t           i;
 414         int              c;
 415
 416         output = NULL;
 417         i = 1;
 418         SQL_BIND_INT64(db, s, i, id);
 419         SQL_BIND_INT64(db, s, i, outbit);
 420         while (SQLITE_ROW == (c = sqlite3_step(s))) {
 421                 if (NULL == output) {
 422                         oldoutput = "";
 423                         sep1 = "";
 424                 } else {
 425                         oldoutput = output;
 426                         sep1 = " # ";
 427                 }
 428                 data = sqlite3_column_text(s, 1);
 429                 if (-1 == asprintf(&newoutput, "%s%s%s",
 430                     oldoutput, sep1, data)) {
 431                         perror(0);
 432                         exit((int)MANDOCLEVEL_SYSERR);
 433                 }
 434                 free(output);
 435                 output = newoutput;
 436         }
 437         if (SQLITE_DONE != c)
 438                 fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 439         sqlite3_reset(s);
 440         return(output);
 441 }
 442
 443 /*
 444  * Implement substring match as an application-defined SQL function.
 445  * Using the SQL LIKE or GLOB operators instead would be a bad idea
 446  * because that would require escaping metacharacters in the string
 447  * being searched for.
 448  */
 449 static void
 450 sql_match(sqlite3_context *context, int argc, sqlite3_value **argv)
 451 {
 452
 453         assert(2 == argc);
 454         sqlite3_result_int(context, NULL != strcasestr(
 455             (const char *)sqlite3_value_text(argv[1]),
 456             (const char *)sqlite3_value_text(argv[0])));
 457 }
 458
 459 /*
 460  * Implement regular expression match
 461  * as an application-defined SQL function.
 462  */
 463 static void
 464 sql_regexp(sqlite3_context *context, int argc, sqlite3_value **argv)
 465 {
 466
 467         assert(2 == argc);
 468         sqlite3_result_int(context, !regexec(
 469             (regex_t *)sqlite3_value_blob(argv[0]),
 470             (const char *)sqlite3_value_text(argv[1]),
 471             0, NULL, 0));
 472 }
 473
 474 static void
 475 sql_append(char **sql, size_t *sz, const char *newstr, int count)
 476 {
 477         size_t           newsz;
 478
 479         newsz = 1 < count ? (size_t)count : strlen(newstr);
 480         *sql = mandoc_realloc(*sql, *sz + newsz + 1);
 481         if (1 < count)
 482                 memset(*sql + *sz, *newstr, (size_t)count);
 483         else
 484                 memcpy(*sql + *sz, newstr, newsz);
 485         *sz += newsz;
 486         (*sql)[*sz] = '\0';
 487 }
 488
 489 /*
 490  * Prepare the search SQL statement.
 491  */
 492 static char *
 493 sql_statement(const struct expr *e)
 494 {
 495         char            *sql;
 496         size_t           sz;
 497         int              needop;
 498
 499         sql = mandoc_strdup("SELECT * FROM mpages WHERE ");
 500         sz = strlen(sql);
 501
 502         for (needop = 0; NULL != e; e = e->next) {
 503                 if (e->and)
 504                         sql_append(&sql, &sz, " AND ", 1);
 505                 else if (needop)
 506                         sql_append(&sql, &sz, " OR ", 1);
 507                 if (e->open)
 508                         sql_append(&sql, &sz, "(", e->open);
 509                 sql_append(&sql, &sz, NULL == e->substr ?
 510                     "id IN (SELECT pageid FROM keys "
 511                     "WHERE key REGEXP ? AND bits & ?)" :
 512                     "id IN (SELECT pageid FROM keys "
 513                     "WHERE key MATCH ? AND bits & ?)", 1);
 514                 if (e->close)
 515                         sql_append(&sql, &sz, ")", e->close);
 516                 needop = 1;
 517         }
 518
 519         return(sql);
 520 }
 521
 522 /*
 523  * Compile a set of string tokens into an expression.
 524  * Tokens in "argv" are assumed to be individual expression atoms (e.g.,
 525  * "(", "foo=bar", etc.).
 526  */
 527 static struct expr *
 528 exprcomp(const struct mansearch *search, int argc, char *argv[])
 529 {
 530         int              i, toopen, logic, igncase, toclose;
 531         struct expr     *first, *next, *cur;
 532
 533         first = cur = NULL;
 534         logic = igncase = toclose = 0;
 535         toopen = 1;
 536
 537         for (i = 0; i < argc; i++) {
 538                 if (0 == strcmp("(", argv[i])) {
 539                         if (igncase)
 540                                 goto fail;
 541                         toopen++;
 542                         toclose++;
 543                         continue;
 544                 } else if (0 == strcmp(")", argv[i])) {
 545                         if (toopen || logic || igncase || NULL == cur)
 546                                 goto fail;
 547                         cur->close++;
 548                         if (0 > --toclose)
 549                                 goto fail;
 550                         continue;
 551                 } else if (0 == strcmp("-a", argv[i])) {
 552                         if (toopen || logic || igncase || NULL == cur)
 553                                 goto fail;
 554                         logic = 1;
 555                         continue;
 556                 } else if (0 == strcmp("-o", argv[i])) {
 557                         if (toopen || logic || igncase || NULL == cur)
 558                                 goto fail;
 559                         logic = 2;
 560                         continue;
 561                 } else if (0 == strcmp("-i", argv[i])) {
 562                         if (igncase)
 563                                 goto fail;
 564                         igncase = 1;
 565                         continue;
 566                 }
 567                 next = exprterm(search, argv[i], !igncase);
 568                 if (NULL == next)
 569                         goto fail;
 570                 next->open = toopen;
 571                 next->and = (1 == logic);
 572                 if (NULL != first) {
 573                         cur->next = next;
 574                         cur = next;
 575                 } else
 576                         cur = first = next;
 577                 toopen = logic = igncase = 0;
 578         }
 579         if (toopen || logic || igncase || toclose)
 580                 goto fail;
 581
 582         cur->close++;
 583         cur = exprspec(cur, TYPE_arch, search->arch, "^(%s|any)$");
 584         exprspec(cur, TYPE_sec, search->sec, "^%s$");
 585
 586         return(first);
 587
 588 fail:
 589         if (NULL != first)
 590                 exprfree(first);
 591         return(NULL);
 592 }
 593
 594 static struct expr *
 595 exprspec(struct expr *cur, uint64_t key, const char *value,
 596                 const char *format)
 597 {
 598         char     errbuf[BUFSIZ];
 599         char    *cp;
 600         int      irc;
 601
 602         if (NULL == value)
 603                 return(cur);
 604
 605         if (-1 == asprintf(&cp, format, value)) {
 606                 perror(0);
 607                 exit((int)MANDOCLEVEL_SYSERR);
 608         }
 609         cur->next = mandoc_calloc(1, sizeof(struct expr));
 610         cur = cur->next;
 611         cur->and = 1;
 612         cur->bits = key;
 613         if (0 != (irc = regcomp(&cur->regexp, cp,
 614             REG_EXTENDED | REG_NOSUB | REG_ICASE))) {
 615                 regerror(irc, &cur->regexp, errbuf, sizeof(errbuf));
 616                 fprintf(stderr, "regcomp: %s\n", errbuf);
 617                 cur->substr = value;
 618         }
 619         free(cp);
 620         return(cur);
 621 }
 622
 623 static struct expr *
 624 exprterm(const struct mansearch *search, char *buf, int cs)
 625 {
 626         char             errbuf[BUFSIZ];
 627         struct expr     *e;
 628         char            *key, *v;
 629         uint64_t         iterbit;
 630         int              i, irc;
 631
 632         if ('\0' == *buf)
 633                 return(NULL);
 634
 635         e = mandoc_calloc(1, sizeof(struct expr));
 636
 637         /*"whatis" mode uses an opaque string and default fields. */
 638
 639         if (MANSEARCH_WHATIS & search->flags) {
 640                 e->substr = buf;
 641                 e->bits = search->deftype;
 642                 return(e);
 643         }
 644
 645         /*
 646          * If no =~ is specified, search with equality over names and
 647          * descriptions.
 648          * If =~ begins the phrase, use name and description fields.
 649          */
 650
 651         if (NULL == (v = strpbrk(buf, "=~"))) {
 652                 e->substr = buf;
 653                 e->bits = search->deftype;
 654                 return(e);
 655         } else if (v == buf)
 656                 e->bits = search->deftype;
 657
 658         if ('~' == *v++) {
 659                 if (NULL != strstr(buf, "arch"))
 660                         cs = 0;
 661                 if (0 != (irc = regcomp(&e->regexp, v,
 662                     REG_EXTENDED | REG_NOSUB | (cs ? 0 : REG_ICASE)))) {
 663                         regerror(irc, &e->regexp, errbuf, sizeof(errbuf));
 664                         fprintf(stderr, "regcomp: %s\n", errbuf);
 665                         free(e);
 666                         return(NULL);
 667                 }
 668         } else
 669                 e->substr = v;
 670         v[-1] = '\0';
 671
 672         /*
 673          * Parse out all possible fields.
 674          * If the field doesn't resolve, bail.
 675          */
 676
 677         while (NULL != (key = strsep(&buf, ","))) {
 678                 if ('\0' == *key)
 679                         continue;
 680                 for (i = 0, iterbit = 1;
 681                      i < mansearch_keymax;
 682                      i++, iterbit <<= 1) {
 683                         if (0 == strcasecmp(key,
 684                             mansearch_keynames[i])) {
 685                                 e->bits |= iterbit;
 686                                 break;
 687                         }
 688                 }
 689                 if (i == mansearch_keymax) {
 690                         if (strcasecmp(key, "any")) {
 691                                 free(e);
 692                                 return(NULL);
 693                         }
 694                         e->bits |= ~0ULL;
 695                 }
 696         }
 697
 698         return(e);
 699 }
 700
 701 static void
 702 exprfree(struct expr *p)
 703 {
 704         struct expr     *pp;
 705
 706         while (NULL != p) {
 707                 pp = p->next;
 708                 free(p);
 709                 p = pp;
 710         }
 711 }
 712
 713 static void *
 714 hash_halloc(size_t sz, void *arg)
 715 {
 716
 717         return(mandoc_calloc(sz, 1));
 718 }
 719
 720 static void *
 721 hash_alloc(size_t sz, void *arg)
 722 {
 723
 724         return(mandoc_malloc(sz));
 725 }
 726
 727 static void
 728 hash_free(void *p, size_t sz, void *arg)
 729 {
 730
 731         free(p);
 732 }