gtk2/gtk/gtksearchenginetracker.c

470 lines
14 KiB
C

/*
* Copyright (C) 2009-2010 Nokia <ivan.frade@nokia.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
*
* Authors: Jürg Billeter <juerg.billeter@codethink.co.uk>
* Martyn Russell <martyn@lanedo.com>
*
* Based on nautilus-search-engine-tracker.c
*/
#include "config.h"
#include <gio/gio.h>
#include <gmodule.h>
#include <gdk/gdk.h>
#include "gtksearchenginetracker.h"
/* If defined, we use fts:match, this has to be enabled in Tracker to
* work which it usually is. The alternative is to undefine it and
* use filename matching instead. This doesn't use the content of the
* file however.
*/
#undef FTS_MATCHING
#define MODULE_FILENAME "libtracker-sparql-0.10.so.0"
#define MODULE_MAP(a) { #a, (gpointer *)&a }
/* Connection object */
typedef struct _TrackerSparqlConnection TrackerSparqlConnection;
#define TRACKER_SPARQL_TYPE_CONNECTION (tracker_sparql_connection_get_type ())
#define TRACKER_SPARQL_CONNECTION(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), TRACKER_SPARQL_TYPE_CONNECTION, TrackerSparqlConnection))
/* Cursor object */
typedef struct _TrackerSparqlCursor TrackerSparqlCursor;
#define TRACKER_SPARQL_TYPE_CURSOR (tracker_sparql_cursor_get_type ())
#define TRACKER_SPARQL_CURSOR(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), TRACKER_SPARQL_TYPE_CURSOR, TrackerSparqlCursor))
/* API */
static GType (*tracker_sparql_connection_get_type) (void) = NULL;
static TrackerSparqlConnection * (*tracker_sparql_connection_get) (GCancellable *cancellable,
GError **error) = NULL;
static void (*tracker_sparql_connection_query_async) (TrackerSparqlConnection *self,
const gchar *sparql,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data) = NULL;
static TrackerSparqlCursor * (*tracker_sparql_connection_query_finish) (TrackerSparqlConnection *self,
GAsyncResult *_res_,
GError **error) = NULL;
static GType (*tracker_sparql_cursor_get_type) (void) = NULL;
static void (*tracker_sparql_cursor_next_async) (TrackerSparqlCursor *self,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data) = NULL;
static gboolean (*tracker_sparql_cursor_next_finish) (TrackerSparqlCursor *self,
GAsyncResult *_res_,
GError **error) = NULL;
static const gchar * (*tracker_sparql_cursor_get_string) (TrackerSparqlCursor *self,
gint *column,
glong *length) = NULL;
static gchar * (*tracker_sparql_escape_string) (const gchar *literal) = NULL;
static struct TrackerFunctions
{
const char *name;
gpointer *pointer;
} funcs[] = {
MODULE_MAP (tracker_sparql_connection_get_type),
MODULE_MAP (tracker_sparql_connection_get),
MODULE_MAP (tracker_sparql_connection_query_async),
MODULE_MAP (tracker_sparql_connection_query_finish),
MODULE_MAP (tracker_sparql_cursor_get_type),
MODULE_MAP (tracker_sparql_cursor_next_async),
MODULE_MAP (tracker_sparql_cursor_next_finish),
MODULE_MAP (tracker_sparql_cursor_get_string),
MODULE_MAP (tracker_sparql_escape_string)
};
static gboolean
init (void)
{
static gboolean inited = FALSE;
gint i;
GModule *m;
GModuleFlags flags;
if (inited)
return TRUE;
flags = G_MODULE_BIND_LAZY | G_MODULE_BIND_LOCAL;
/* Only support 0.10 onwards */
if ((m = g_module_open (MODULE_FILENAME, flags)) == NULL)
{
g_debug ("No tracker backend available or it is not new enough");
g_debug ("Only available using '%s'", MODULE_FILENAME);
return FALSE;
}
inited = TRUE;
/* Check for the symbols we need */
for (i = 0; i < G_N_ELEMENTS (funcs); i++)
{
if (!g_module_symbol (m, funcs[i].name, funcs[i].pointer))
{
g_warning ("Missing symbol '%s' in libtracker-sparql\n",
funcs[i].name);
g_module_close (m);
for (i = 0; i < G_N_ELEMENTS (funcs); i++)
funcs[i].pointer = NULL;
return FALSE;
}
}
return TRUE;
}
/*
* GtkSearchEngineTracker object
*/
struct _GtkSearchEngineTrackerPrivate
{
TrackerSparqlConnection *connection;
GCancellable *cancellable;
GtkQuery *query;
gboolean query_pending;
};
G_DEFINE_TYPE (GtkSearchEngineTracker, _gtk_search_engine_tracker, GTK_TYPE_SEARCH_ENGINE);
static void cursor_callback (GObject *object,
GAsyncResult *result,
gpointer user_data);
static void
finalize (GObject *object)
{
GtkSearchEngineTracker *tracker;
tracker = GTK_SEARCH_ENGINE_TRACKER (object);
if (tracker->priv->cancellable)
{
g_cancellable_cancel (tracker->priv->cancellable);
g_object_unref (tracker->priv->cancellable);
tracker->priv->cancellable = NULL;
}
if (tracker->priv->query)
{
g_object_unref (tracker->priv->query);
tracker->priv->query = NULL;
}
if (tracker->priv->connection)
{
g_object_unref (tracker->priv->connection);
tracker->priv->connection = NULL;
}
G_OBJECT_CLASS (_gtk_search_engine_tracker_parent_class)->finalize (object);
}
static void
cursor_next (GtkSearchEngineTracker *tracker,
TrackerSparqlCursor *cursor)
{
tracker_sparql_cursor_next_async (cursor,
tracker->priv->cancellable,
cursor_callback,
tracker);
}
static void
cursor_callback (GObject *object,
GAsyncResult *result,
gpointer user_data)
{
GtkSearchEngineTracker *tracker;
GError *error = NULL;
TrackerSparqlCursor *cursor;
GList *hits;
gboolean success;
gdk_threads_enter ();
tracker = GTK_SEARCH_ENGINE_TRACKER (user_data);
cursor = TRACKER_SPARQL_CURSOR (object);
success = tracker_sparql_cursor_next_finish (cursor, result, &error);
if (error)
{
_gtk_search_engine_error (GTK_SEARCH_ENGINE (tracker), error->message);
g_error_free (error);
if (cursor)
g_object_unref (cursor);
gdk_threads_leave ();
return;
}
if (!success)
{
_gtk_search_engine_finished (GTK_SEARCH_ENGINE (tracker));
if (cursor)
g_object_unref (cursor);
gdk_threads_leave ();
return;
}
/* We iterate result by result, not n at a time. */
hits = g_list_append (NULL, (gchar*) tracker_sparql_cursor_get_string (cursor, 0, NULL));
_gtk_search_engine_hits_added (GTK_SEARCH_ENGINE (tracker), hits);
g_list_free (hits);
/* Get next */
cursor_next (tracker, cursor);
gdk_threads_leave ();
}
static void
query_callback (GObject *object,
GAsyncResult *result,
gpointer user_data)
{
GtkSearchEngineTracker *tracker;
TrackerSparqlConnection *connection;
TrackerSparqlCursor *cursor;
GError *error = NULL;
gdk_threads_enter ();
tracker = GTK_SEARCH_ENGINE_TRACKER (user_data);
tracker->priv->query_pending = FALSE;
connection = TRACKER_SPARQL_CONNECTION (object);
cursor = tracker_sparql_connection_query_finish (connection,
result,
&error);
if (error)
{
_gtk_search_engine_error (GTK_SEARCH_ENGINE (tracker), error->message);
g_error_free (error);
gdk_threads_leave ();
return;
}
if (!cursor)
{
_gtk_search_engine_finished (GTK_SEARCH_ENGINE (tracker));
gdk_threads_leave ();
return;
}
cursor_next (tracker, cursor);
gdk_threads_leave ();
}
static void
sparql_append_string_literal (GString *sparql,
const gchar *str)
{
gchar *s;
s = tracker_sparql_escape_string (str);
g_string_append_c (sparql, '"');
g_string_append (sparql, s);
g_string_append_c (sparql, '"');
g_free (s);
}
static void
gtk_search_engine_tracker_start (GtkSearchEngine *engine)
{
GtkSearchEngineTracker *tracker;
gchar *search_text;
#ifdef FTS_MATCHING
gchar *location_uri;
#endif
GString *sparql;
tracker = GTK_SEARCH_ENGINE_TRACKER (engine);
if (tracker->priv->query_pending)
{
g_debug ("Attempt to start a new search while one is pending, doing nothing");
return;
}
if (tracker->priv->query == NULL)
{
g_debug ("Attempt to start a new search with no GtkQuery, doing nothing");
return;
}
search_text = _gtk_query_get_text (tracker->priv->query);
#ifdef FTS_MATCHING
location_uri = _gtk_query_get_location (tracker->priv->query);
/* Using FTS: */
sparql = g_string_new ("SELECT nie:url(?urn) "
"WHERE {"
" ?urn a nfo:FileDataObject ;"
" tracker:available true ; "
" fts:match ");
sparql_append_string_literal (sparql, search_text);
if (location_uri)
{
g_string_append (sparql, " . FILTER (fn:starts-with(nie:url(?urn),");
sparql_append_string_literal (sparql, location_uri);
g_string_append (sparql, "))");
}
g_string_append (sparql, " } ORDER BY DESC(fts:rank(?urn)) ASC(nie:url(?urn))");
#else /* FTS_MATCHING */
/* Using filename matching: */
sparql = g_string_new ("SELECT nie:url(?urn) "
"WHERE {"
" ?urn a nfo:FileDataObject ;"
" tracker:available true ."
" FILTER (fn:contains(nfo:fileName(?urn),");
sparql_append_string_literal (sparql, search_text);
g_string_append (sparql,
"))"
"} ORDER BY DESC(nie:url(?urn)) DESC(nfo:fileName(?urn))");
#endif /* FTS_MATCHING */
tracker_sparql_connection_query_async (tracker->priv->connection,
sparql->str,
tracker->priv->cancellable,
query_callback,
tracker);
g_string_free (sparql, TRUE);
tracker->priv->query_pending = TRUE;
g_free (search_text);
}
static void
gtk_search_engine_tracker_stop (GtkSearchEngine *engine)
{
GtkSearchEngineTracker *tracker;
tracker = GTK_SEARCH_ENGINE_TRACKER (engine);
if (tracker->priv->query && tracker->priv->query_pending)
{
g_cancellable_cancel (tracker->priv->cancellable);
tracker->priv->query_pending = FALSE;
}
}
static gboolean
gtk_search_engine_tracker_is_indexed (GtkSearchEngine *engine)
{
return TRUE;
}
static void
gtk_search_engine_tracker_set_query (GtkSearchEngine *engine,
GtkQuery *query)
{
GtkSearchEngineTracker *tracker;
tracker = GTK_SEARCH_ENGINE_TRACKER (engine);
if (query)
g_object_ref (query);
if (tracker->priv->query)
g_object_unref (tracker->priv->query);
tracker->priv->query = query;
}
static void
_gtk_search_engine_tracker_class_init (GtkSearchEngineTrackerClass *class)
{
GObjectClass *gobject_class;
GtkSearchEngineClass *engine_class;
gobject_class = G_OBJECT_CLASS (class);
gobject_class->finalize = finalize;
engine_class = GTK_SEARCH_ENGINE_CLASS (class);
engine_class->set_query = gtk_search_engine_tracker_set_query;
engine_class->start = gtk_search_engine_tracker_start;
engine_class->stop = gtk_search_engine_tracker_stop;
engine_class->is_indexed = gtk_search_engine_tracker_is_indexed;
g_type_class_add_private (gobject_class, sizeof (GtkSearchEngineTrackerPrivate));
}
static void
_gtk_search_engine_tracker_init (GtkSearchEngineTracker *engine)
{
engine->priv = G_TYPE_INSTANCE_GET_PRIVATE (engine,
GTK_TYPE_SEARCH_ENGINE_TRACKER,
GtkSearchEngineTrackerPrivate);
}
GtkSearchEngine *
_gtk_search_engine_tracker_new (void)
{
GtkSearchEngineTracker *engine;
TrackerSparqlConnection *connection;
GCancellable *cancellable;
GError *error = NULL;
if (!init ())
return NULL;
cancellable = g_cancellable_new ();
connection = tracker_sparql_connection_get (cancellable, &error);
if (error)
{
g_warning ("Could not establish a connection to Tracker: %s", error->message);
g_error_free (error);
return NULL;
}
else if (!connection)
{
g_warning ("Could not establish a connection to Tracker, no TrackerSparqlConnection was returned");
return NULL;
}
engine = g_object_new (GTK_TYPE_SEARCH_ENGINE_TRACKER, NULL);
engine->priv->connection = connection;
engine->priv->cancellable = cancellable;
engine->priv->query_pending = FALSE;
return GTK_SEARCH_ENGINE (engine);
}