mansearch.c

   1 /*      $Id: mansearch.c,v 1.53 2015/01/20 18:21:18 schwarze Exp $ */
   2 /*
   3  * Copyright (c) 2012 Kristaps Dzonsons <kristaps@bsd.lv>
   4  * Copyright (c) 2013, 2014, 2015 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 #include "config.h"
  19
  20 #include <sys/mman.h>
  21 #include <sys/types.h>
  22
  23 #include <assert.h>
  24 #include <errno.h>
  25 #include <fcntl.h>
  26 #include <getopt.h>
  27 #include <limits.h>
  28 #include <regex.h>
  29 #include <stdio.h>
  30 #include <stdint.h>
  31 #include <stddef.h>
  32 #include <stdlib.h>
  33 #include <string.h>
  34 #include <unistd.h>
  35
  36 #if HAVE_OHASH
  37 #include <ohash.h>
  38 #else
  39 #include "compat_ohash.h"
  40 #endif
  41 #include <sqlite3.h>
  42 #ifndef SQLITE_DETERMINISTIC
  43 #define SQLITE_DETERMINISTIC 0
  44 #endif
  45
  46 #include "mandoc.h"
  47 #include "mandoc_aux.h"
  48 #include "manpath.h"
  49 #include "mansearch.h"
  50
  51 extern int mansearch_keymax;
  52 extern const char *const mansearch_keynames[];
  53
  54 #define SQL_BIND_TEXT(_db, _s, _i, _v) \
  55         do { if (SQLITE_OK != sqlite3_bind_text \
  56                 ((_s), (_i)++, (_v), -1, SQLITE_STATIC)) \
  57                 fprintf(stderr, "%s\n", sqlite3_errmsg((_db))); \
  58         } while (0)
  59 #define SQL_BIND_INT64(_db, _s, _i, _v) \
  60         do { if (SQLITE_OK != sqlite3_bind_int64 \
  61                 ((_s), (_i)++, (_v))) \
  62                 fprintf(stderr, "%s\n", sqlite3_errmsg((_db))); \
  63         } while (0)
  64 #define SQL_BIND_BLOB(_db, _s, _i, _v) \
  65         do { if (SQLITE_OK != sqlite3_bind_blob \
  66                 ((_s), (_i)++, (&_v), sizeof(_v), SQLITE_STATIC)) \
  67                 fprintf(stderr, "%s\n", sqlite3_errmsg((_db))); \
  68         } while (0)
  69
  70 struct  expr {
  71         regex_t          regexp;  /* compiled regexp, if applicable */
  72         const char      *substr;  /* to search for, if applicable */
  73         struct expr     *next;    /* next in sequence */
  74         uint64_t         bits;    /* type-mask */
  75         int              equal;   /* equality, not subsring match */
  76         int              open;    /* opening parentheses before */
  77         int              and;     /* logical AND before */
  78         int              close;   /* closing parentheses after */
  79 };
  80
  81 struct  match {
  82         uint64_t         pageid; /* identifier in database */
  83         uint64_t         bits; /* name type mask */
  84         char            *desc; /* manual page description */
  85         int              form; /* bit field: formatted, zipped? */
  86 };
  87
  88 static  void             buildnames(const struct mansearch *,
  89                                 struct manpage *, sqlite3 *,
  90                                 sqlite3_stmt *, uint64_t,
  91                                 const char *, int form);
  92 static  char            *buildoutput(sqlite3 *, sqlite3_stmt *,
  93                                  uint64_t, uint64_t);
  94 static  void            *hash_alloc(size_t, void *);
  95 static  void             hash_free(void *, void *);
  96 static  void            *hash_calloc(size_t, size_t, void *);
  97 static  struct expr     *exprcomp(const struct mansearch *,
  98                                 int, char *[]);
  99 static  void             exprfree(struct expr *);
 100 static  struct expr     *exprterm(const struct mansearch *, char *, int);
 101 static  int              manpage_compare(const void *, const void *);
 102 static  void             sql_append(char **sql, size_t *sz,
 103                                 const char *newstr, int count);
 104 static  void             sql_match(sqlite3_context *context,
 105                                 int argc, sqlite3_value **argv);
 106 static  void             sql_regexp(sqlite3_context *context,
 107                                 int argc, sqlite3_value **argv);
 108 static  char            *sql_statement(const struct expr *);
 109
 110
 111 int
 112 mansearch_setup(int start)
 113 {
 114         static void     *pagecache;
 115         int              c;
 116
 117 #define PC_PAGESIZE     1280
 118 #define PC_NUMPAGES     256
 119
 120         if (start) {
 121                 if (NULL != pagecache) {
 122                         fprintf(stderr, "pagecache already enabled\n");
 123                         return((int)MANDOCLEVEL_BADARG);
 124                 }
 125
 126                 pagecache = mmap(NULL, PC_PAGESIZE * PC_NUMPAGES,
 127                     PROT_READ | PROT_WRITE,
 128                     MAP_SHARED | MAP_ANON, -1, 0);
 129
 130                 if (MAP_FAILED == pagecache) {
 131                         perror("mmap");
 132                         pagecache = NULL;
 133                         return((int)MANDOCLEVEL_SYSERR);
 134                 }
 135
 136                 c = sqlite3_config(SQLITE_CONFIG_PAGECACHE,
 137                     pagecache, PC_PAGESIZE, PC_NUMPAGES);
 138
 139                 if (SQLITE_OK == c)
 140                         return((int)MANDOCLEVEL_OK);
 141
 142                 fprintf(stderr, "pagecache: %s\n", sqlite3_errstr(c));
 143
 144         } else if (NULL == pagecache) {
 145                 fprintf(stderr, "pagecache missing\n");
 146                 return((int)MANDOCLEVEL_BADARG);
 147         }
 148
 149         if (-1 == munmap(pagecache, PC_PAGESIZE * PC_NUMPAGES)) {
 150                 perror("munmap");
 151                 pagecache = NULL;
 152                 return((int)MANDOCLEVEL_SYSERR);
 153         }
 154
 155         pagecache = NULL;
 156         return((int)MANDOCLEVEL_OK);
 157 }
 158
 159 int
 160 mansearch(const struct mansearch *search,
 161                 const struct manpaths *paths,
 162                 int argc, char *argv[],
 163                 struct manpage **res, size_t *sz)
 164 {
 165         int              fd, rc, c, indexbit;
 166         int64_t          pageid;
 167         uint64_t         outbit, iterbit;
 168         char             buf[PATH_MAX];
 169         char            *sql;
 170         struct manpage  *mpage;
 171         struct expr     *e, *ep;
 172         sqlite3         *db;
 173         sqlite3_stmt    *s, *s2;
 174         struct match    *mp;
 175         struct ohash_info info;
 176         struct ohash     htab;
 177         unsigned int     idx;
 178         size_t           i, j, cur, maxres;
 179
 180         info.calloc = hash_calloc;
 181         info.alloc = hash_alloc;
 182         info.free = hash_free;
 183         info.key_offset = offsetof(struct match, pageid);
 184
 185         *sz = cur = maxres = 0;
 186         sql = NULL;
 187         *res = NULL;
 188         fd = -1;
 189         e = NULL;
 190         rc = 0;
 191
 192         if (0 == argc)
 193                 goto out;
 194         if (NULL == (e = exprcomp(search, argc, argv)))
 195                 goto out;
 196
 197         outbit = 0;
 198         if (NULL != search->outkey) {
 199                 for (indexbit = 0, iterbit = 1;
 200                      indexbit < mansearch_keymax;
 201                      indexbit++, iterbit <<= 1) {
 202                         if (0 == strcasecmp(search->outkey,
 203                             mansearch_keynames[indexbit])) {
 204                                 outbit = iterbit;
 205                                 break;
 206                         }
 207                 }
 208         }
 209
 210         /*
 211          * Save a descriptor to the current working directory.
 212          * Since pathnames in the "paths" variable might be relative,
 213          * and we'll be chdir()ing into them, we need to keep a handle
 214          * on our current directory from which to start the chdir().
 215          */
 216
 217         if (NULL == getcwd(buf, PATH_MAX)) {
 218                 perror("getcwd");
 219                 goto out;
 220         } else if (-1 == (fd = open(buf, O_RDONLY, 0))) {
 221                 perror(buf);
 222                 goto out;
 223         }
 224
 225         sql = sql_statement(e);
 226
 227         /*
 228          * Loop over the directories (containing databases) for us to
 229          * search.
 230          * Don't let missing/bad databases/directories phase us.
 231          * In each, try to open the resident database and, if it opens,
 232          * scan it for our match expression.
 233          */
 234
 235         for (i = 0; i < paths->sz; i++) {
 236                 if (-1 == fchdir(fd)) {
 237                         perror(buf);
 238                         free(*res);
 239                         break;
 240                 } else if (-1 == chdir(paths->paths[i])) {
 241                         perror(paths->paths[i]);
 242                         continue;
 243                 }
 244
 245                 c = sqlite3_open_v2(MANDOC_DB, &db,
 246                     SQLITE_OPEN_READONLY, NULL);
 247
 248                 if (SQLITE_OK != c) {
 249                         fprintf(stderr, "%s/%s: %s\n",
 250                             paths->paths[i], MANDOC_DB, strerror(errno));
 251                         sqlite3_close(db);
 252                         continue;
 253                 }
 254
 255                 /*
 256                  * Define the SQL functions for substring
 257                  * and regular expression matching.
 258                  */
 259
 260                 c = sqlite3_create_function(db, "match", 2,
 261                     SQLITE_UTF8 | SQLITE_DETERMINISTIC,
 262                     NULL, sql_match, NULL, NULL);
 263                 assert(SQLITE_OK == c);
 264                 c = sqlite3_create_function(db, "regexp", 2,
 265                     SQLITE_UTF8 | SQLITE_DETERMINISTIC,
 266                     NULL, sql_regexp, NULL, NULL);
 267                 assert(SQLITE_OK == c);
 268
 269                 j = 1;
 270                 c = sqlite3_prepare_v2(db, sql, -1, &s, NULL);
 271                 if (SQLITE_OK != c)
 272                         fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 273
 274                 for (ep = e; NULL != ep; ep = ep->next) {
 275                         if (NULL == ep->substr) {
 276                                 SQL_BIND_BLOB(db, s, j, ep->regexp);
 277                         } else
 278                                 SQL_BIND_TEXT(db, s, j, ep->substr);
 279                         if (0 == ((TYPE_Nd | TYPE_Nm) & ep->bits))
 280                                 SQL_BIND_INT64(db, s, j, ep->bits);
 281                 }
 282
 283                 memset(&htab, 0, sizeof(struct ohash));
 284                 ohash_init(&htab, 4, &info);
 285
 286                 /*
 287                  * Hash each entry on its [unique] document identifier.
 288                  * This is a uint64_t.
 289                  * Instead of using a hash function, simply convert the
 290                  * uint64_t to a uint32_t, the hash value's type.
 291                  * This gives good performance and preserves the
 292                  * distribution of buckets in the table.
 293                  */
 294                 while (SQLITE_ROW == (c = sqlite3_step(s))) {
 295                         pageid = sqlite3_column_int64(s, 2);
 296                         idx = ohash_lookup_memory(&htab,
 297                             (char *)&pageid, sizeof(uint64_t),
 298                             (uint32_t)pageid);
 299
 300                         if (NULL != ohash_find(&htab, idx))
 301                                 continue;
 302
 303                         mp = mandoc_calloc(1, sizeof(struct match));
 304                         mp->pageid = pageid;
 305                         mp->form = sqlite3_column_int(s, 1);
 306                         mp->bits = sqlite3_column_int64(s, 3);
 307                         if (TYPE_Nd == outbit)
 308                                 mp->desc = mandoc_strdup((const char *)
 309                                     sqlite3_column_text(s, 0));
 310                         ohash_insert(&htab, idx, mp);
 311                 }
 312
 313                 if (SQLITE_DONE != c)
 314                         fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 315
 316                 sqlite3_finalize(s);
 317
 318                 c = sqlite3_prepare_v2(db,
 319                     "SELECT sec, arch, name, pageid FROM mlinks "
 320                     "WHERE pageid=? ORDER BY sec, arch, name",
 321                     -1, &s, NULL);
 322                 if (SQLITE_OK != c)
 323                         fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 324
 325                 c = sqlite3_prepare_v2(db,
 326                     "SELECT bits, key, pageid FROM keys "
 327                     "WHERE pageid=? AND bits & ?",
 328                     -1, &s2, NULL);
 329                 if (SQLITE_OK != c)
 330                         fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 331
 332                 for (mp = ohash_first(&htab, &idx);
 333                                 NULL != mp;
 334                                 mp = ohash_next(&htab, &idx)) {
 335                         if (cur + 1 > maxres) {
 336                                 maxres += 1024;
 337                                 *res = mandoc_reallocarray(*res,
 338                                     maxres, sizeof(struct manpage));
 339                         }
 340                         mpage = *res + cur;
 341                         mpage->ipath = i;
 342                         mpage->bits = mp->bits;
 343                         mpage->sec = 10;
 344                         mpage->form = mp->form;
 345                         buildnames(search, mpage, db, s, mp->pageid,
 346                             paths->paths[i], mp->form);
 347                         if (mpage->names != NULL) {
 348                                 mpage->output = TYPE_Nd & outbit ?
 349                                     mp->desc : outbit ?
 350                                     buildoutput(db, s2, mp->pageid, outbit) :
 351                                     NULL;
 352                                 cur++;
 353                         }
 354                         free(mp);
 355                 }
 356
 357                 sqlite3_finalize(s);
 358                 sqlite3_finalize(s2);
 359                 sqlite3_close(db);
 360                 ohash_delete(&htab);
 361
 362                 /*
 363                  * In man(1) mode, prefer matches in earlier trees
 364                  * over matches in later trees.
 365                  */
 366
 367                 if (cur && search->firstmatch)
 368                         break;
 369         }
 370         qsort(*res, cur, sizeof(struct manpage), manpage_compare);
 371         rc = 1;
 372 out:
 373         if (-1 != fd) {
 374                 if (-1 == fchdir(fd))
 375                         perror(buf);
 376                 close(fd);
 377         }
 378         exprfree(e);
 379         free(sql);
 380         *sz = cur;
 381         return(rc);
 382 }
 383
 384 void
 385 mansearch_free(struct manpage *res, size_t sz)
 386 {
 387         size_t   i;
 388
 389         for (i = 0; i < sz; i++) {
 390                 free(res[i].file);
 391                 free(res[i].names);
 392                 free(res[i].output);
 393         }
 394         free(res);
 395 }
 396
 397 static int
 398 manpage_compare(const void *vp1, const void *vp2)
 399 {
 400         const struct manpage    *mp1, *mp2;
 401         int                      diff;
 402
 403         mp1 = vp1;
 404         mp2 = vp2;
 405         return( (diff = mp2->bits - mp1->bits) ? diff :
 406                 (diff = mp1->sec - mp2->sec) ? diff :
 407                 strcasecmp(mp1->names, mp2->names));
 408 }
 409
 410 static void
 411 buildnames(const struct mansearch *search, struct manpage *mpage,
 412                 sqlite3 *db, sqlite3_stmt *s,
 413                 uint64_t pageid, const char *path, int form)
 414 {
 415         char            *newnames, *prevsec, *prevarch;
 416         const char      *oldnames, *sep1, *name, *sec, *sep2, *arch, *fsec;
 417         size_t           i;
 418         int              c;
 419
 420         mpage->file = NULL;
 421         mpage->names = NULL;
 422         prevsec = prevarch = NULL;
 423         i = 1;
 424         SQL_BIND_INT64(db, s, i, pageid);
 425         while (SQLITE_ROW == (c = sqlite3_step(s))) {
 426
 427                 /* Decide whether we already have some names. */
 428
 429                 if (NULL == mpage->names) {
 430                         oldnames = "";
 431                         sep1 = "";
 432                 } else {
 433                         oldnames = mpage->names;
 434                         sep1 = ", ";
 435                 }
 436
 437                 /* Fetch the next name, rejecting sec/arch mismatches. */
 438
 439                 sec = (const char *)sqlite3_column_text(s, 0);
 440                 if (search->sec != NULL && strcasecmp(sec, search->sec))
 441                         continue;
 442                 arch = (const char *)sqlite3_column_text(s, 1);
 443                 if (search->arch != NULL && *arch != '\0' &&
 444                     strcasecmp(arch, search->arch))
 445                         continue;
 446                 name = (const char *)sqlite3_column_text(s, 2);
 447
 448                 /* Remember the first section found. */
 449
 450                 if (9 < mpage->sec && '1' <= *sec && '9' >= *sec)
 451                         mpage->sec = (*sec - '1') + 1;
 452
 453                 /* If the section changed, append the old one. */
 454
 455                 if (NULL != prevsec &&
 456                     (strcmp(sec, prevsec) ||
 457                      strcmp(arch, prevarch))) {
 458                         sep2 = '\0' == *prevarch ? "" : "/";
 459                         mandoc_asprintf(&newnames, "%s(%s%s%s)",
 460                             oldnames, prevsec, sep2, prevarch);
 461                         free(mpage->names);
 462                         oldnames = mpage->names = newnames;
 463                         free(prevsec);
 464                         free(prevarch);
 465                         prevsec = prevarch = NULL;
 466                 }
 467
 468                 /* Save the new section, to append it later. */
 469
 470                 if (NULL == prevsec) {
 471                         prevsec = mandoc_strdup(sec);
 472                         prevarch = mandoc_strdup(arch);
 473                 }
 474
 475                 /* Append the new name. */
 476
 477                 mandoc_asprintf(&newnames, "%s%s%s",
 478                     oldnames, sep1, name);
 479                 free(mpage->names);
 480                 mpage->names = newnames;
 481
 482                 /* Also save the first file name encountered. */
 483
 484                 if (mpage->file != NULL)
 485                         continue;
 486
 487                 if (form & FORM_SRC) {
 488                         sep1 = "man";
 489                         fsec = sec;
 490                 } else {
 491                         sep1 = "cat";
 492                         fsec = "0";
 493                 }
 494                 sep2 = *arch == '\0' ? "" : "/";
 495                 mandoc_asprintf(&mpage->file, "%s/%s%s%s%s/%s.%s",
 496                     path, sep1, sec, sep2, arch, name, fsec);
 497         }
 498         if (c != SQLITE_DONE)
 499                 fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 500         sqlite3_reset(s);
 501
 502         /* Append one final section to the names. */
 503
 504         if (prevsec != NULL) {
 505                 sep2 = *prevarch == '\0' ? "" : "/";
 506                 mandoc_asprintf(&newnames, "%s(%s%s%s)",
 507                     mpage->names, prevsec, sep2, prevarch);
 508                 free(mpage->names);
 509                 mpage->names = newnames;
 510                 free(prevsec);
 511                 free(prevarch);
 512         }
 513 }
 514
 515 static char *
 516 buildoutput(sqlite3 *db, sqlite3_stmt *s, uint64_t pageid, uint64_t outbit)
 517 {
 518         char            *output, *newoutput;
 519         const char      *oldoutput, *sep1, *data;
 520         size_t           i;
 521         int              c;
 522
 523         output = NULL;
 524         i = 1;
 525         SQL_BIND_INT64(db, s, i, pageid);
 526         SQL_BIND_INT64(db, s, i, outbit);
 527         while (SQLITE_ROW == (c = sqlite3_step(s))) {
 528                 if (NULL == output) {
 529                         oldoutput = "";
 530                         sep1 = "";
 531                 } else {
 532                         oldoutput = output;
 533                         sep1 = " # ";
 534                 }
 535                 data = (const char *)sqlite3_column_text(s, 1);
 536                 mandoc_asprintf(&newoutput, "%s%s%s",
 537                     oldoutput, sep1, data);
 538                 free(output);
 539                 output = newoutput;
 540         }
 541         if (SQLITE_DONE != c)
 542                 fprintf(stderr, "%s\n", sqlite3_errmsg(db));
 543         sqlite3_reset(s);
 544         return(output);
 545 }
 546
 547 /*
 548  * Implement substring match as an application-defined SQL function.
 549  * Using the SQL LIKE or GLOB operators instead would be a bad idea
 550  * because that would require escaping metacharacters in the string
 551  * being searched for.
 552  */
 553 static void
 554 sql_match(sqlite3_context *context, int argc, sqlite3_value **argv)
 555 {
 556
 557         assert(2 == argc);
 558         sqlite3_result_int(context, NULL != strcasestr(
 559             (const char *)sqlite3_value_text(argv[1]),
 560             (const char *)sqlite3_value_text(argv[0])));
 561 }
 562
 563 /*
 564  * Implement regular expression match
 565  * as an application-defined SQL function.
 566  */
 567 static void
 568 sql_regexp(sqlite3_context *context, int argc, sqlite3_value **argv)
 569 {
 570
 571         assert(2 == argc);
 572         sqlite3_result_int(context, !regexec(
 573             (regex_t *)sqlite3_value_blob(argv[0]),
 574             (const char *)sqlite3_value_text(argv[1]),
 575             0, NULL, 0));
 576 }
 577
 578 static void
 579 sql_append(char **sql, size_t *sz, const char *newstr, int count)
 580 {
 581         size_t           newsz;
 582
 583         newsz = 1 < count ? (size_t)count : strlen(newstr);
 584         *sql = mandoc_realloc(*sql, *sz + newsz + 1);
 585         if (1 < count)
 586                 memset(*sql + *sz, *newstr, (size_t)count);
 587         else
 588                 memcpy(*sql + *sz, newstr, newsz);
 589         *sz += newsz;
 590         (*sql)[*sz] = '\0';
 591 }
 592
 593 /*
 594  * Prepare the search SQL statement.
 595  */
 596 static char *
 597 sql_statement(const struct expr *e)
 598 {
 599         char            *sql;
 600         size_t           sz;
 601         int              needop;
 602
 603         sql = mandoc_strdup(e->equal ?
 604             "SELECT desc, form, pageid, bits "
 605                 "FROM mpages NATURAL JOIN names WHERE " :
 606             "SELECT desc, form, pageid, 0 FROM mpages WHERE ");
 607         sz = strlen(sql);
 608
 609         for (needop = 0; NULL != e; e = e->next) {
 610                 if (e->and)
 611                         sql_append(&sql, &sz, " AND ", 1);
 612                 else if (needop)
 613                         sql_append(&sql, &sz, " OR ", 1);
 614                 if (e->open)
 615                         sql_append(&sql, &sz, "(", e->open);
 616                 sql_append(&sql, &sz,
 617                     TYPE_Nd & e->bits
 618                     ? (NULL == e->substr
 619                         ? "desc REGEXP ?"
 620                         : "desc MATCH ?")
 621                     : TYPE_Nm == e->bits
 622                     ? (NULL == e->substr
 623                         ? "pageid IN (SELECT pageid FROM names "
 624                           "WHERE name REGEXP ?)"
 625                         : e->equal
 626                         ? "name = ? "
 627                         : "pageid IN (SELECT pageid FROM names "
 628                           "WHERE name MATCH ?)")
 629                     : (NULL == e->substr
 630                         ? "pageid IN (SELECT pageid FROM keys "
 631                           "WHERE key REGEXP ? AND bits & ?)"
 632                         : "pageid IN (SELECT pageid FROM keys "
 633                           "WHERE key MATCH ? AND bits & ?)"), 1);
 634                 if (e->close)
 635                         sql_append(&sql, &sz, ")", e->close);
 636                 needop = 1;
 637         }
 638
 639         return(sql);
 640 }
 641
 642 /*
 643  * Compile a set of string tokens into an expression.
 644  * Tokens in "argv" are assumed to be individual expression atoms (e.g.,
 645  * "(", "foo=bar", etc.).
 646  */
 647 static struct expr *
 648 exprcomp(const struct mansearch *search, int argc, char *argv[])
 649 {
 650         uint64_t         mask;
 651         int              i, toopen, logic, igncase, toclose;
 652         struct expr     *first, *prev, *cur, *next;
 653
 654         first = cur = NULL;
 655         logic = igncase = toopen = toclose = 0;
 656
 657         for (i = 0; i < argc; i++) {
 658                 if (0 == strcmp("(", argv[i])) {
 659                         if (igncase)
 660                                 goto fail;
 661                         toopen++;
 662                         toclose++;
 663                         continue;
 664                 } else if (0 == strcmp(")", argv[i])) {
 665                         if (toopen || logic || igncase || NULL == cur)
 666                                 goto fail;
 667                         cur->close++;
 668                         if (0 > --toclose)
 669                                 goto fail;
 670                         continue;
 671                 } else if (0 == strcmp("-a", argv[i])) {
 672                         if (toopen || logic || igncase || NULL == cur)
 673                                 goto fail;
 674                         logic = 1;
 675                         continue;
 676                 } else if (0 == strcmp("-o", argv[i])) {
 677                         if (toopen || logic || igncase || NULL == cur)
 678                                 goto fail;
 679                         logic = 2;
 680                         continue;
 681                 } else if (0 == strcmp("-i", argv[i])) {
 682                         if (igncase)
 683                                 goto fail;
 684                         igncase = 1;
 685                         continue;
 686                 }
 687                 next = exprterm(search, argv[i], !igncase);
 688                 if (NULL == next)
 689                         goto fail;
 690                 if (NULL == first)
 691                         first = next;
 692                 else
 693                         cur->next = next;
 694                 prev = cur = next;
 695
 696                 /*
 697                  * Searching for descriptions must be split out
 698                  * because they are stored in the mpages table,
 699                  * not in the keys table.
 700                  */
 701
 702                 for (mask = TYPE_Nm; mask <= TYPE_Nd; mask <<= 1) {
 703                         if (mask & cur->bits && ~mask & cur->bits) {
 704                                 next = mandoc_calloc(1,
 705                                     sizeof(struct expr));
 706                                 memcpy(next, cur, sizeof(struct expr));
 707                                 prev->open = 1;
 708                                 cur->bits = mask;
 709                                 cur->next = next;
 710                                 cur = next;
 711                                 cur->bits &= ~mask;
 712                         }
 713                 }
 714                 prev->and = (1 == logic);
 715                 prev->open += toopen;
 716                 if (cur != prev)
 717                         cur->close = 1;
 718
 719                 toopen = logic = igncase = 0;
 720         }
 721         if ( ! (toopen || logic || igncase || toclose))
 722                 return(first);
 723
 724 fail:
 725         if (NULL != first)
 726                 exprfree(first);
 727         return(NULL);
 728 }
 729
 730 static struct expr *
 731 exprterm(const struct mansearch *search, char *buf, int cs)
 732 {
 733         char             errbuf[BUFSIZ];
 734         struct expr     *e;
 735         char            *key, *val;
 736         uint64_t         iterbit;
 737         int              i, irc;
 738
 739         if ('\0' == *buf)
 740                 return(NULL);
 741
 742         e = mandoc_calloc(1, sizeof(struct expr));
 743
 744         if (search->argmode == ARG_NAME) {
 745                 e->bits = TYPE_Nm;
 746                 e->substr = buf;
 747                 e->equal = 1;
 748                 return(e);
 749         }
 750
 751         /*
 752          * Separate macro keys from search string.
 753          * If needed, request regular expression handling
 754          * by setting e->substr to NULL.
 755          */
 756
 757         if (search->argmode == ARG_WORD) {
 758                 e->bits = TYPE_Nm;
 759                 e->substr = NULL;
 760                 mandoc_asprintf(&val, "[[:<:]]%s[[:>:]]", buf);
 761                 cs = 0;
 762         } else if ((val = strpbrk(buf, "=~")) == NULL) {
 763                 e->bits = TYPE_Nm | TYPE_Nd;
 764                 e->substr = buf;
 765         } else {
 766                 if (val == buf)
 767                         e->bits = TYPE_Nm | TYPE_Nd;
 768                 if ('=' == *val)
 769                         e->substr = val + 1;
 770                 *val++ = '\0';
 771                 if (NULL != strstr(buf, "arch"))
 772                         cs = 0;
 773         }
 774
 775         /* Compile regular expressions. */
 776
 777         if (NULL == e->substr) {
 778                 irc = regcomp(&e->regexp, val,
 779                     REG_EXTENDED | REG_NOSUB | (cs ? 0 : REG_ICASE));
 780                 if (search->argmode == ARG_WORD)
 781                         free(val);
 782                 if (irc) {
 783                         regerror(irc, &e->regexp, errbuf, sizeof(errbuf));
 784                         fprintf(stderr, "regcomp: %s\n", errbuf);
 785                         free(e);
 786                         return(NULL);
 787                 }
 788         }
 789
 790         if (e->bits)
 791                 return(e);
 792
 793         /*
 794          * Parse out all possible fields.
 795          * If the field doesn't resolve, bail.
 796          */
 797
 798         while (NULL != (key = strsep(&buf, ","))) {
 799                 if ('\0' == *key)
 800                         continue;
 801                 for (i = 0, iterbit = 1;
 802                      i < mansearch_keymax;
 803                      i++, iterbit <<= 1) {
 804                         if (0 == strcasecmp(key,
 805                             mansearch_keynames[i])) {
 806                                 e->bits |= iterbit;
 807                                 break;
 808                         }
 809                 }
 810                 if (i == mansearch_keymax) {
 811                         if (strcasecmp(key, "any")) {
 812                                 free(e);
 813                                 return(NULL);
 814                         }
 815                         e->bits |= ~0ULL;
 816                 }
 817         }
 818
 819         return(e);
 820 }
 821
 822 static void
 823 exprfree(struct expr *p)
 824 {
 825         struct expr     *pp;
 826
 827         while (NULL != p) {
 828                 pp = p->next;
 829                 free(p);
 830                 p = pp;
 831         }
 832 }
 833
 834 static void *
 835 hash_calloc(size_t nmemb, size_t sz, void *arg)
 836 {
 837
 838         return(mandoc_calloc(nmemb, sz));
 839 }
 840
 841 static void *
 842 hash_alloc(size_t sz, void *arg)
 843 {
 844
 845         return(mandoc_malloc(sz));
 846 }
 847
 848 static void
 849 hash_free(void *p, void *arg)
 850 {
 851
 852         free(p);
 853 }