notmuch/query.cc
Carl Worth 4ca1492f1b Add destroy functions for results, message, and tags.
None of these are strictly necessary, (everything was leak-free
without them), but notmuch_message_destroy can actually be useful
for when one query has many message results, but only one is needed
to be live at a time.

The destroy functions for results and tags are fairly gratuitous, as
there's unlikely to be any benefit from calling them. But they're all
easy to add, (all of these functions are just wrappers for talloc_free),
and we do so for consistency and completeness.
2009-10-20 22:24:59 -07:00

149 lines
3.7 KiB
C++

/* query.cc - Support for searching a notmuch database
*
* Copyright © 2009 Carl Worth
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see http://www.gnu.org/licenses/ .
*
* Author: Carl Worth <cworth@cworth.org>
*/
#include "notmuch-private.h"
#include "database-private.h"
#include <xapian.h>
const char *NOTMUCH_QUERY_ALL = "";
struct _notmuch_query {
notmuch_database_t *notmuch;
const char *query_string;
notmuch_sort_t sort;
};
struct _notmuch_results {
notmuch_database_t *notmuch;
Xapian::PostingIterator iterator;
Xapian::PostingIterator iterator_end;
};
notmuch_query_t *
notmuch_query_create (notmuch_database_t *notmuch,
const char *query_string)
{
notmuch_query_t *query;
query = talloc (NULL, notmuch_query_t);
if (unlikely (query == NULL))
return NULL;
query->notmuch = notmuch;
/* Special-case NOTMUCH_QUERY_ALL so we see it and not a copy. */
if (query_string == NOTMUCH_QUERY_ALL)
query->query_string = query_string;
else
query->query_string = talloc_strdup (query, query_string);
query->sort = NOTMUCH_SORT_DATE_OLDEST_FIRST;
return query;
}
void
notmuch_query_set_sort (notmuch_query_t *query, notmuch_sort_t sort)
{
query->sort = sort;
}
/* We end up having to call the destructors explicitly because we had
* to use "placement new" in order to initialize C++ objects within a
* block that we allocated with talloc. So C++ is making talloc
* slightly less simple to use, (we wouldn't need
* talloc_set_destructor at all otherwise).
*/
static int
_notmuch_results_destructor (notmuch_results_t *results)
{
results->iterator.~PostingIterator ();
results->iterator_end.~PostingIterator ();
return 0;
}
notmuch_results_t *
notmuch_query_search (notmuch_query_t *query)
{
notmuch_results_t *results;
results = talloc (query, notmuch_results_t);
if (unlikely (results == NULL))
return NULL;
try {
if (query->query_string != NOTMUCH_QUERY_ALL) {
fprintf (stderr, "Error: Arbitrary search strings are not supported yet. Come back soon!\n");
exit (1);
}
results->notmuch = query->notmuch;
new (&results->iterator) Xapian::PostingIterator ();
new (&results->iterator_end) Xapian::PostingIterator ();
talloc_set_destructor (results, _notmuch_results_destructor);
results->iterator = query->notmuch->xapian_db->postlist_begin ("");
results->iterator_end = query->notmuch->xapian_db->postlist_end ("");
} catch (const Xapian::Error &error) {
fprintf (stderr, "A Xapian exception occurred: %s\n",
error.get_msg().c_str());
}
return results;
}
void
notmuch_query_destroy (notmuch_query_t *query)
{
talloc_free (query);
}
notmuch_bool_t
notmuch_results_has_more (notmuch_results_t *results)
{
return (results->iterator != results->iterator_end);
}
notmuch_message_t *
notmuch_results_get (notmuch_results_t *results)
{
Xapian::docid doc_id;
doc_id = *results->iterator;
return _notmuch_message_create (results,
results->notmuch, doc_id);
}
void
notmuch_results_advance (notmuch_results_t *results)
{
results->iterator++;
}
void
notmuch_results_destroy (notmuch_results_t *results)
{
talloc_free (results);
}