git.cworth.org Git - notmuch/blob - lib/query.cc

   1 /* query.cc - Support for searching a notmuch database
   2  *
   3  * Copyright © 2009 Carl Worth
   4  *
   5  * This program is free software: you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation, either version 3 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see https://www.gnu.org/licenses/ .
  17  *
  18  * Author: Carl Worth <cworth@cworth.org>
  19  */
  20
  21 #include "notmuch-private.h"
  22 #include "database-private.h"
  23
  24 #include <glib.h> /* GHashTable, GPtrArray */
  25
  26 struct _notmuch_query {
  27     notmuch_database_t *notmuch;
  28     const char *query_string;
  29     notmuch_sort_t sort;
  30     notmuch_string_list_t *exclude_terms;
  31     notmuch_exclude_t omit_excluded;
  32     bool parsed;
  33     Xapian::Query xapian_query;
  34     std::set<std::string> terms;
  35 };
  36
  37 typedef struct _notmuch_mset_messages {
  38     notmuch_messages_t base;
  39     notmuch_database_t *notmuch;
  40     Xapian::MSetIterator iterator;
  41     Xapian::MSetIterator iterator_end;
  42 } notmuch_mset_messages_t;
  43
  44 struct _notmuch_doc_id_set {
  45     unsigned char *bitmap;
  46     unsigned int bound;
  47 };
  48
  49 #define DOCIDSET_WORD(bit) ((bit) / CHAR_BIT)
  50 #define DOCIDSET_BIT(bit) ((bit) % CHAR_BIT)
  51
  52 struct _notmuch_threads {
  53     notmuch_query_t *query;
  54
  55     /* The ordered list of doc ids matched by the query. */
  56     GArray *doc_ids;
  57     /* Our iterator's current position in doc_ids. */
  58     unsigned int doc_id_pos;
  59     /* The set of matched docid's that have not been assigned to a
  60      * thread. Initially, this contains every docid in doc_ids. */
  61     notmuch_doc_id_set_t match_set;
  62 };
  63
  64 /* We need this in the message functions so forward declare. */
  65 static bool
  66 _notmuch_doc_id_set_init (void *ctx,
  67                           notmuch_doc_id_set_t *doc_ids,
  68                           GArray *arr);
  69
  70 static bool
  71 _debug_query (void)
  72 {
  73     char *env = getenv ("NOTMUCH_DEBUG_QUERY");
  74
  75     return (env && strcmp (env, "") != 0);
  76 }
  77
  78 /* Explicit destructor call for placement new */
  79 static int
  80 _notmuch_query_destructor (notmuch_query_t *query)
  81 {
  82     query->xapian_query.~Query();
  83     query->terms.~set<std::string>();
  84     return 0;
  85 }
  86
  87 static notmuch_query_t *
  88 _notmuch_query_constructor (notmuch_database_t *notmuch,
  89                             const char *query_string)
  90 {
  91     notmuch_query_t *query;
  92
  93     if (_debug_query ())
  94         fprintf (stderr, "Query string is:\n%s\n", query_string);
  95
  96     query = talloc (notmuch, notmuch_query_t);
  97     if (unlikely (query == NULL))
  98         return NULL;
  99
 100     new (&query->xapian_query) Xapian::Query ();
 101     new (&query->terms) std::set<std::string> ();
 102     query->parsed = false;
 103
 104     talloc_set_destructor (query, _notmuch_query_destructor);
 105
 106     query->notmuch = notmuch;
 107
 108     query->query_string = talloc_strdup (query, query_string);
 109
 110     query->sort = NOTMUCH_SORT_NEWEST_FIRST;
 111
 112     query->exclude_terms = _notmuch_string_list_create (query);
 113
 114     query->omit_excluded = NOTMUCH_EXCLUDE_TRUE;
 115
 116     return query;
 117 }
 118
 119 notmuch_query_t *
 120 notmuch_query_create (notmuch_database_t *notmuch,
 121                       const char *query_string)
 122 {
 123
 124     notmuch_query_t *query = _notmuch_query_constructor (notmuch, query_string);
 125
 126     if (! query)
 127         return NULL;
 128
 129     return query;
 130 }
 131
 132 static notmuch_status_t
 133 _notmuch_query_ensure_parsed (notmuch_query_t *query)
 134 {
 135     if (query->parsed)
 136         return NOTMUCH_STATUS_SUCCESS;
 137
 138     try {
 139         query->xapian_query =
 140             query->notmuch->query_parser->
 141             parse_query (query->query_string, NOTMUCH_QUERY_PARSER_FLAGS);
 142
 143         /* Xapian doesn't support skip_to on terms from a query since
 144          *  they are unordered, so cache a copy of all terms in
 145          *  something searchable.
 146          */
 147
 148         for (Xapian::TermIterator t = query->xapian_query.get_terms_begin ();
 149              t != query->xapian_query.get_terms_end (); ++t)
 150             query->terms.insert (*t);
 151
 152         query->parsed = true;
 153
 154     } catch (const Xapian::Error &error) {
 155         if (! query->notmuch->exception_reported) {
 156             _notmuch_database_log (query->notmuch,
 157                                    "A Xapian exception occurred parsing query: %s\n",
 158                                    error.get_msg ().c_str ());
 159             _notmuch_database_log_append (query->notmuch,
 160                                           "Query string was: %s\n",
 161                                           query->query_string);
 162             query->notmuch->exception_reported = true;
 163         }
 164
 165         return NOTMUCH_STATUS_XAPIAN_EXCEPTION;
 166     }
 167     return NOTMUCH_STATUS_SUCCESS;
 168 }
 169
 170 const char *
 171 notmuch_query_get_query_string (const notmuch_query_t *query)
 172 {
 173     return query->query_string;
 174 }
 175
 176 void
 177 notmuch_query_set_omit_excluded (notmuch_query_t *query,
 178                                  notmuch_exclude_t omit_excluded)
 179 {
 180     query->omit_excluded = omit_excluded;
 181 }
 182
 183 void
 184 notmuch_query_set_sort (notmuch_query_t *query, notmuch_sort_t sort)
 185 {
 186     query->sort = sort;
 187 }
 188
 189 notmuch_sort_t
 190 notmuch_query_get_sort (const notmuch_query_t *query)
 191 {
 192     return query->sort;
 193 }
 194
 195 notmuch_status_t
 196 notmuch_query_add_tag_exclude (notmuch_query_t *query, const char *tag)
 197 {
 198     notmuch_status_t status;
 199     char *term;
 200
 201     status = _notmuch_query_ensure_parsed (query);
 202     if (status)
 203         return status;
 204
 205     term = talloc_asprintf (query, "%s%s", _find_prefix ("tag"), tag);
 206     if (query->terms.count (term) != 0)
 207         return NOTMUCH_STATUS_IGNORED;
 208
 209     _notmuch_string_list_append (query->exclude_terms, term);
 210     return NOTMUCH_STATUS_SUCCESS;
 211 }
 212
 213 /* We end up having to call the destructors explicitly because we had
 214  * to use "placement new" in order to initialize C++ objects within a
 215  * block that we allocated with talloc. So C++ is making talloc
 216  * slightly less simple to use, (we wouldn't need
 217  * talloc_set_destructor at all otherwise).
 218  */
 219 static int
 220 _notmuch_messages_destructor (notmuch_mset_messages_t *messages)
 221 {
 222     messages->iterator.~MSetIterator ();
 223     messages->iterator_end.~MSetIterator ();
 224
 225     return 0;
 226 }
 227
 228 /* Return a query that matches messages with the excluded tags
 229  * registered with query. The caller of this function has to combine the returned
 230  * query appropriately.*/
 231 static Xapian::Query
 232 _notmuch_exclude_tags (notmuch_query_t *query)
 233 {
 234     Xapian::Query exclude_query = Xapian::Query::MatchNothing;
 235
 236     for (notmuch_string_node_t *term = query->exclude_terms->head; term;
 237          term = term->next) {
 238         exclude_query = Xapian::Query (Xapian::Query::OP_OR,
 239                                        exclude_query, Xapian::Query (term->string));
 240     }
 241     return exclude_query;
 242 }
 243
 244
 245 notmuch_status_t
 246 notmuch_query_search_messages_st (notmuch_query_t *query,
 247                                   notmuch_messages_t **out)
 248 {
 249     return notmuch_query_search_messages (query, out);
 250 }
 251
 252 notmuch_status_t
 253 notmuch_query_search_messages (notmuch_query_t *query,
 254                                notmuch_messages_t **out)
 255 {
 256     return _notmuch_query_search_documents (query, "mail", out);
 257 }
 258
 259 notmuch_status_t
 260 _notmuch_query_search_documents (notmuch_query_t *query,
 261                                  const char *type,
 262                                  notmuch_messages_t **out)
 263 {
 264     notmuch_database_t *notmuch = query->notmuch;
 265     const char *query_string = query->query_string;
 266     notmuch_mset_messages_t *messages;
 267     notmuch_status_t status;
 268
 269     status = _notmuch_query_ensure_parsed (query);
 270     if (status)
 271         return status;
 272
 273     messages = talloc (query, notmuch_mset_messages_t);
 274     if (unlikely (messages == NULL))
 275         return NOTMUCH_STATUS_OUT_OF_MEMORY;
 276
 277     try {
 278
 279         messages->base.is_of_list_type = false;
 280         messages->base.iterator = NULL;
 281         messages->notmuch = notmuch;
 282         new (&messages->iterator) Xapian::MSetIterator ();
 283         new (&messages->iterator_end) Xapian::MSetIterator ();
 284
 285         talloc_set_destructor (messages, _notmuch_messages_destructor);
 286
 287         Xapian::Enquire enquire (*notmuch->xapian_db);
 288         Xapian::Query mail_query (talloc_asprintf (query, "%s%s",
 289                                                    _find_prefix ("type"),
 290                                                    type));
 291         Xapian::Query final_query, exclude_query;
 292         Xapian::MSet mset;
 293         Xapian::MSetIterator iterator;
 294
 295         if (strcmp (query_string, "") == 0 ||
 296             strcmp (query_string, "*") == 0) {
 297             final_query = mail_query;
 298         } else {
 299             final_query = Xapian::Query (Xapian::Query::OP_AND,
 300                                          mail_query, query->xapian_query);
 301         }
 302         messages->base.excluded_doc_ids = NULL;
 303
 304         if ((query->omit_excluded != NOTMUCH_EXCLUDE_FALSE) && (query->exclude_terms)) {
 305             exclude_query = _notmuch_exclude_tags (query);
 306
 307             if (query->omit_excluded == NOTMUCH_EXCLUDE_TRUE ||
 308                 query->omit_excluded == NOTMUCH_EXCLUDE_ALL) {
 309                 final_query = Xapian::Query (Xapian::Query::OP_AND_NOT,
 310                                              final_query, exclude_query);
 311             } else { /* NOTMUCH_EXCLUDE_FLAG */
 312                 exclude_query = Xapian::Query (Xapian::Query::OP_AND,
 313                                                exclude_query, final_query);
 314
 315                 enquire.set_weighting_scheme (Xapian::BoolWeight ());
 316                 enquire.set_query (exclude_query);
 317
 318                 mset = enquire.get_mset (0, notmuch->xapian_db->get_doccount ());
 319
 320                 GArray *excluded_doc_ids = g_array_new (false, false, sizeof (unsigned int));
 321
 322                 for (iterator = mset.begin (); iterator != mset.end (); iterator++) {
 323                     unsigned int doc_id = *iterator;
 324                     g_array_append_val (excluded_doc_ids, doc_id);
 325                 }
 326                 messages->base.excluded_doc_ids = talloc (messages, _notmuch_doc_id_set);
 327                 _notmuch_doc_id_set_init (query, messages->base.excluded_doc_ids,
 328                                           excluded_doc_ids);
 329                 g_array_unref (excluded_doc_ids);
 330             }
 331         }
 332
 333
 334         enquire.set_weighting_scheme (Xapian::BoolWeight ());
 335
 336         switch (query->sort) {
 337         case NOTMUCH_SORT_OLDEST_FIRST:
 338             enquire.set_sort_by_value (NOTMUCH_VALUE_TIMESTAMP, false);
 339             break;
 340         case NOTMUCH_SORT_NEWEST_FIRST:
 341             enquire.set_sort_by_value (NOTMUCH_VALUE_TIMESTAMP, true);
 342             break;
 343         case NOTMUCH_SORT_MESSAGE_ID:
 344             enquire.set_sort_by_value (NOTMUCH_VALUE_MESSAGE_ID, false);
 345             break;
 346         case NOTMUCH_SORT_UNSORTED:
 347             break;
 348         }
 349
 350         if (_debug_query ()) {
 351             fprintf (stderr, "Exclude query is:\n%s\n",
 352                      exclude_query.get_description ().c_str ());
 353             fprintf (stderr, "Final query is:\n%s\n",
 354                      final_query.get_description ().c_str ());
 355         }
 356
 357         enquire.set_query (final_query);
 358
 359         mset = enquire.get_mset (0, notmuch->xapian_db->get_doccount ());
 360
 361         messages->iterator = mset.begin ();
 362         messages->iterator_end = mset.end ();
 363
 364         *out = &messages->base;
 365         return NOTMUCH_STATUS_SUCCESS;
 366
 367     } catch (const Xapian::Error &error) {
 368         _notmuch_database_log (notmuch,
 369                                "A Xapian exception occurred performing query: %s\n",
 370                                error.get_msg ().c_str ());
 371         _notmuch_database_log_append (notmuch,
 372                                       "Query string was: %s\n",
 373                                       query->query_string);
 374
 375         notmuch->exception_reported = true;
 376         talloc_free (messages);
 377         return NOTMUCH_STATUS_XAPIAN_EXCEPTION;
 378     }
 379 }
 380
 381 bool
 382 _notmuch_mset_messages_valid (notmuch_messages_t *messages)
 383 {
 384     notmuch_mset_messages_t *mset_messages;
 385
 386     mset_messages = (notmuch_mset_messages_t *) messages;
 387
 388     return (mset_messages->iterator != mset_messages->iterator_end);
 389 }
 390
 391 static Xapian::docid
 392 _notmuch_mset_messages_get_doc_id (notmuch_messages_t *messages)
 393 {
 394     notmuch_mset_messages_t *mset_messages;
 395
 396     mset_messages = (notmuch_mset_messages_t *) messages;
 397
 398     if (! _notmuch_mset_messages_valid (&mset_messages->base))
 399         return 0;
 400
 401     return *mset_messages->iterator;
 402 }
 403
 404 notmuch_message_t *
 405 _notmuch_mset_messages_get (notmuch_messages_t *messages)
 406 {
 407     notmuch_message_t *message;
 408     Xapian::docid doc_id;
 409     notmuch_private_status_t status;
 410     notmuch_mset_messages_t *mset_messages;
 411
 412     mset_messages = (notmuch_mset_messages_t *) messages;
 413
 414     if (! _notmuch_mset_messages_valid (&mset_messages->base))
 415         return NULL;
 416
 417     doc_id = *mset_messages->iterator;
 418
 419     message = _notmuch_message_create (mset_messages,
 420                                        mset_messages->notmuch, doc_id,
 421                                        &status);
 422
 423     if (message == NULL &&
 424         status == NOTMUCH_PRIVATE_STATUS_NO_DOCUMENT_FOUND) {
 425         INTERNAL_ERROR ("a messages iterator contains a non-existent document ID.\n");
 426     }
 427
 428     if (messages->excluded_doc_ids &&
 429         _notmuch_doc_id_set_contains (messages->excluded_doc_ids, doc_id))
 430         notmuch_message_set_flag (message, NOTMUCH_MESSAGE_FLAG_EXCLUDED, true);
 431
 432     return message;
 433 }
 434
 435 void
 436 _notmuch_mset_messages_move_to_next (notmuch_messages_t *messages)
 437 {
 438     notmuch_mset_messages_t *mset_messages;
 439
 440     mset_messages = (notmuch_mset_messages_t *) messages;
 441
 442     mset_messages->iterator++;
 443 }
 444
 445 static bool
 446 _notmuch_doc_id_set_init (void *ctx,
 447                           notmuch_doc_id_set_t *doc_ids,
 448                           GArray *arr)
 449 {
 450     unsigned int max = 0;
 451     unsigned char *bitmap;
 452
 453     for (unsigned int i = 0; i < arr->len; i++)
 454         max = MAX (max, g_array_index (arr, unsigned int, i));
 455     bitmap = talloc_zero_array (ctx, unsigned char, DOCIDSET_WORD (max) + 1);
 456
 457     if (bitmap == NULL)
 458         return false;
 459
 460     doc_ids->bitmap = bitmap;
 461     doc_ids->bound = max + 1;
 462
 463     for (unsigned int i = 0; i < arr->len; i++) {
 464         unsigned int doc_id = g_array_index (arr, unsigned int, i);
 465         bitmap[DOCIDSET_WORD (doc_id)] |= 1 << DOCIDSET_BIT (doc_id);
 466     }
 467
 468     return true;
 469 }
 470
 471 bool
 472 _notmuch_doc_id_set_contains (notmuch_doc_id_set_t *doc_ids,
 473                               unsigned int doc_id)
 474 {
 475     if (doc_id >= doc_ids->bound)
 476         return false;
 477     return doc_ids->bitmap[DOCIDSET_WORD (doc_id)] & (1 << DOCIDSET_BIT (doc_id));
 478 }
 479
 480 void
 481 _notmuch_doc_id_set_remove (notmuch_doc_id_set_t *doc_ids,
 482                             unsigned int doc_id)
 483 {
 484     if (doc_id < doc_ids->bound)
 485         doc_ids->bitmap[DOCIDSET_WORD (doc_id)] &= ~(1 << DOCIDSET_BIT (doc_id));
 486 }
 487
 488 /* Glib objects force use to use a talloc destructor as well, (but not
 489  * nearly as ugly as the for messages due to C++ objects). At
 490  * this point, I'd really like to have some talloc-friendly
 491  * equivalents for the few pieces of glib that I'm using. */
 492 static int
 493 _notmuch_threads_destructor (notmuch_threads_t *threads)
 494 {
 495     if (threads->doc_ids)
 496         g_array_unref (threads->doc_ids);
 497
 498     return 0;
 499 }
 500
 501 notmuch_status_t
 502 notmuch_query_search_threads_st (notmuch_query_t *query, notmuch_threads_t **out)
 503 {
 504     return notmuch_query_search_threads (query, out);
 505 }
 506
 507 notmuch_status_t
 508 notmuch_query_search_threads (notmuch_query_t *query,
 509                               notmuch_threads_t **out)
 510 {
 511     notmuch_threads_t *threads;
 512     notmuch_messages_t *messages;
 513     notmuch_status_t status;
 514
 515     threads = talloc (query, notmuch_threads_t);
 516     if (threads == NULL)
 517         return NOTMUCH_STATUS_OUT_OF_MEMORY;
 518     threads->doc_ids = NULL;
 519     talloc_set_destructor (threads, _notmuch_threads_destructor);
 520
 521     threads->query = query;
 522
 523     status = notmuch_query_search_messages (query, &messages);
 524     if (status) {
 525         talloc_free (threads);
 526         return status;
 527     }
 528
 529     threads->doc_ids = g_array_new (false, false, sizeof (unsigned int));
 530     while (notmuch_messages_valid (messages)) {
 531         unsigned int doc_id = _notmuch_mset_messages_get_doc_id (messages);
 532         g_array_append_val (threads->doc_ids, doc_id);
 533         notmuch_messages_move_to_next (messages);
 534     }
 535     threads->doc_id_pos = 0;
 536
 537     talloc_free (messages);
 538
 539     if (! _notmuch_doc_id_set_init (threads, &threads->match_set,
 540                                     threads->doc_ids)) {
 541         talloc_free (threads);
 542         return NOTMUCH_STATUS_OUT_OF_MEMORY;
 543     }
 544
 545     *out = threads;
 546     return NOTMUCH_STATUS_SUCCESS;
 547 }
 548
 549 void
 550 notmuch_query_destroy (notmuch_query_t *query)
 551 {
 552     talloc_free (query);
 553 }
 554
 555 notmuch_bool_t
 556 notmuch_threads_valid (notmuch_threads_t *threads)
 557 {
 558     unsigned int doc_id;
 559
 560     if (! threads)
 561         return false;
 562
 563     while (threads->doc_id_pos < threads->doc_ids->len) {
 564         doc_id = g_array_index (threads->doc_ids, unsigned int,
 565                                 threads->doc_id_pos);
 566         if (_notmuch_doc_id_set_contains (&threads->match_set, doc_id))
 567             break;
 568
 569         threads->doc_id_pos++;
 570     }
 571
 572     return threads->doc_id_pos < threads->doc_ids->len;
 573 }
 574
 575 notmuch_thread_t *
 576 notmuch_threads_get (notmuch_threads_t *threads)
 577 {
 578     unsigned int doc_id;
 579
 580     if (! notmuch_threads_valid (threads))
 581         return NULL;
 582
 583     doc_id = g_array_index (threads->doc_ids, unsigned int,
 584                             threads->doc_id_pos);
 585     return _notmuch_thread_create (threads->query,
 586                                    threads->query->notmuch,
 587                                    doc_id,
 588                                    &threads->match_set,
 589                                    threads->query->exclude_terms,
 590                                    threads->query->omit_excluded,
 591                                    threads->query->sort);
 592 }
 593
 594 void
 595 notmuch_threads_move_to_next (notmuch_threads_t *threads)
 596 {
 597     threads->doc_id_pos++;
 598 }
 599
 600 void
 601 notmuch_threads_destroy (notmuch_threads_t *threads)
 602 {
 603     talloc_free (threads);
 604 }
 605
 606 notmuch_status_t
 607 notmuch_query_count_messages_st (notmuch_query_t *query, unsigned *count_out)
 608 {
 609     return notmuch_query_count_messages (query, count_out);
 610 }
 611
 612 notmuch_status_t
 613 notmuch_query_count_messages (notmuch_query_t *query, unsigned *count_out)
 614 {
 615     return _notmuch_query_count_documents (query, "mail", count_out);
 616 }
 617
 618 notmuch_status_t
 619 _notmuch_query_count_documents (notmuch_query_t *query, const char *type, unsigned *count_out)
 620 {
 621     notmuch_database_t *notmuch = query->notmuch;
 622     const char *query_string = query->query_string;
 623     Xapian::doccount count = 0;
 624     notmuch_status_t status;
 625
 626     status = _notmuch_query_ensure_parsed (query);
 627     if (status)
 628         return status;
 629
 630     try {
 631         Xapian::Enquire enquire (*notmuch->xapian_db);
 632         Xapian::Query mail_query (talloc_asprintf (query, "%s%s",
 633                                                    _find_prefix ("type"),
 634                                                    type));
 635         Xapian::Query final_query, exclude_query;
 636         Xapian::MSet mset;
 637
 638         if (strcmp (query_string, "") == 0 ||
 639             strcmp (query_string, "*") == 0) {
 640             final_query = mail_query;
 641         } else {
 642             final_query = Xapian::Query (Xapian::Query::OP_AND,
 643                                          mail_query, query->xapian_query);
 644         }
 645
 646         exclude_query = _notmuch_exclude_tags (query);
 647
 648         final_query = Xapian::Query (Xapian::Query::OP_AND_NOT,
 649                                      final_query, exclude_query);
 650
 651         enquire.set_weighting_scheme (Xapian::BoolWeight ());
 652         enquire.set_docid_order (Xapian::Enquire::ASCENDING);
 653
 654         if (_debug_query ()) {
 655             fprintf (stderr, "Exclude query is:\n%s\n",
 656                      exclude_query.get_description ().c_str ());
 657             fprintf (stderr, "Final query is:\n%s\n",
 658                      final_query.get_description ().c_str ());
 659         }
 660
 661         enquire.set_query (final_query);
 662
 663         /*
 664          * Set the checkatleast parameter to the number of documents
 665          * in the database to make get_matches_estimated() exact.
 666          * Set the max parameter to 1 to avoid fetching documents we will discard.
 667          */
 668         mset = enquire.get_mset (0, 1,
 669                                  notmuch->xapian_db->get_doccount ());
 670
 671         count = mset.get_matches_estimated ();
 672
 673     } catch (const Xapian::Error &error) {
 674         _notmuch_database_log (notmuch,
 675                                "A Xapian exception occurred performing query: %s\n",
 676                                error.get_msg ().c_str ());
 677         _notmuch_database_log_append (notmuch,
 678                                       "Query string was: %s\n",
 679                                       query->query_string);
 680         return NOTMUCH_STATUS_XAPIAN_EXCEPTION;
 681     }
 682
 683     *count_out = count;
 684     return NOTMUCH_STATUS_SUCCESS;
 685 }
 686
 687 notmuch_status_t
 688 notmuch_query_count_threads_st (notmuch_query_t *query, unsigned *count)
 689 {
 690     return notmuch_query_count_threads (query, count);
 691 }
 692
 693 notmuch_status_t
 694 notmuch_query_count_threads (notmuch_query_t *query, unsigned *count)
 695 {
 696     notmuch_messages_t *messages;
 697     GHashTable *hash;
 698     notmuch_sort_t sort;
 699     notmuch_status_t ret = NOTMUCH_STATUS_SUCCESS;
 700
 701     sort = query->sort;
 702     query->sort = NOTMUCH_SORT_UNSORTED;
 703     ret = notmuch_query_search_messages (query, &messages);
 704     if (ret)
 705         return ret;
 706     query->sort = sort;
 707     if (messages == NULL)
 708         return NOTMUCH_STATUS_XAPIAN_EXCEPTION;
 709
 710     hash = g_hash_table_new_full (g_str_hash, g_str_equal, NULL, NULL);
 711     if (hash == NULL) {
 712         talloc_free (messages);
 713         return NOTMUCH_STATUS_OUT_OF_MEMORY;
 714     }
 715
 716     while (notmuch_messages_valid (messages)) {
 717         notmuch_message_t *message = notmuch_messages_get (messages);
 718         const char *thread_id = notmuch_message_get_thread_id (message);
 719         char *thread_id_copy = talloc_strdup (messages, thread_id);
 720         if (unlikely (thread_id_copy == NULL)) {
 721             notmuch_message_destroy (message);
 722             ret = NOTMUCH_STATUS_OUT_OF_MEMORY;
 723             goto DONE;
 724         }
 725         g_hash_table_insert (hash, thread_id_copy, NULL);
 726         notmuch_message_destroy (message);
 727         notmuch_messages_move_to_next (messages);
 728     }
 729
 730     *count = g_hash_table_size (hash);
 731
 732   DONE:
 733     g_hash_table_unref (hash);
 734     talloc_free (messages);
 735
 736     return ret;
 737 }
 738
 739 notmuch_database_t *
 740 notmuch_query_get_database (const notmuch_query_t *query)
 741 {
 742     return query->notmuch;
 743 }