[tracker/wip/carlosg/sparql1.1: 55/80] libtracker-data: Drop unused handling of blank nodes

[Carlos Garnacho <carlosg src gnome org>]

commit f9f8584dbaa01c29d8f5774fa698f669c56339e5
Author: Carlos Garnacho <carlosg gnome org>
Date:   Sun Jun 16 20:48:17 2019 +0200

    libtracker-data: Drop unused handling of blank nodes
    
    Since the new sparql parser, we generate UUIDs for blank nodes
    in the TrackerSparql level, having them generated beforehand means
    this special casing of ":" prefixed strings is unused and no longer
    necessary.

 src/libtracker-data/tracker-data-update.c | 257 +-----------------------------
 1 file changed, 4 insertions(+), 253 deletions(-)
---
diff --git a/src/libtracker-data/tracker-data-update.c b/src/libtracker-data/tracker-data-update.c
index 844b39abe..bbfae4260 100644
--- a/src/libtracker-data/tracker-data-update.c
+++ b/src/libtracker-data/tracker-data-update.c
@@ -109,19 +109,6 @@ struct _TrackerDataUpdateBufferTable {
        GArray *properties;
 };
 
-/* buffer for anonymous blank nodes
- * that are not yet in the database */
-struct _TrackerDataBlankBuffer {
-       GHashTable *table;
-       gchar *subject;
-       /* string */
-       GArray *predicates;
-       /* string */
-       GArray *objects;
-       /* string */
-       GArray *graphs;
-};
-
 struct _TrackerStatementDelegate {
        TrackerStatementCallback callback;
        gpointer user_data;
@@ -143,7 +130,6 @@ struct _TrackerData {
 
        /* current resource */
        TrackerDataUpdateBufferResource *resource_buffer;
-       TrackerDataBlankBuffer blank_buffer;
        time_t resource_time;
        gint transaction_modseq;
        gboolean has_persistent;
@@ -1124,82 +1110,6 @@ tracker_data_update_buffer_clear (TrackerData *data)
        }
 }
 
-static void
-tracker_data_blank_buffer_flush (TrackerData  *data,
-                                 GError      **error)
-{
-       /* end of blank node */
-       gint i;
-       gint id;
-       gchar *subject;
-       gchar *blank_uri;
-       const gchar *sha1;
-       GChecksum *checksum;
-       GError *actual_error = NULL;
-       TrackerDBInterface *iface;
-
-       subject = data->blank_buffer.subject;
-       data->blank_buffer.subject = NULL;
-
-       /* we share anonymous blank nodes with identical properties
-          to avoid blowing up the database with duplicates */
-
-       checksum = g_checksum_new (G_CHECKSUM_SHA1);
-
-       /* generate hash uri from data to find resource
-          assumes no collisions due to generally little contents of anonymous nodes */
-       for (i = 0; i < data->blank_buffer.predicates->len; i++) {
-               if (g_array_index (data->blank_buffer.graphs, guchar *, i) != NULL) {
-                       g_checksum_update (checksum, g_array_index (data->blank_buffer.graphs, guchar *, i), 
-1);
-               }
-
-               g_checksum_update (checksum, g_array_index (data->blank_buffer.predicates, guchar *, i), -1);
-               g_checksum_update (checksum, g_array_index (data->blank_buffer.objects, guchar *, i), -1);
-       }
-
-       sha1 = g_checksum_get_string (checksum);
-
-       /* generate name based uuid */
-       blank_uri = g_strdup_printf ("urn:uuid:%.8s-%.4s-%.4s-%.4s-%.12s",
-                                    sha1, sha1 + 8, sha1 + 12, sha1 + 16, sha1 + 20);
-
-       iface = tracker_data_manager_get_writable_db_interface (data->manager);
-       id = tracker_data_query_resource_id (data->manager, iface, blank_uri);
-
-       if (id == 0) {
-               /* uri not found
-                  replay piled up statements to create resource */
-               for (i = 0; i < data->blank_buffer.predicates->len; i++) {
-                       tracker_data_insert_statement (data,
-                                                      g_array_index (data->blank_buffer.graphs, gchar *, i),
-                                                      blank_uri,
-                                                      g_array_index (data->blank_buffer.predicates, gchar *, 
i),
-                                                      g_array_index (data->blank_buffer.objects, gchar *, i),
-                                                      &actual_error);
-                       if (actual_error) {
-                               break;
-                       }
-               }
-       }
-
-       /* free piled up statements */
-       for (i = 0; i < data->blank_buffer.predicates->len; i++) {
-               g_free (g_array_index (data->blank_buffer.graphs, gchar *, i));
-               g_free (g_array_index (data->blank_buffer.predicates, gchar *, i));
-               g_free (g_array_index (data->blank_buffer.objects, gchar *, i));
-       }
-       g_array_remove_range (data->blank_buffer.graphs, 0, data->blank_buffer.graphs->len);
-       g_array_remove_range (data->blank_buffer.predicates, 0, data->blank_buffer.predicates->len);
-       g_array_remove_range (data->blank_buffer.objects, 0, data->blank_buffer.objects->len);
-
-       g_hash_table_insert (data->blank_buffer.table, subject, blank_uri);
-       g_checksum_free (checksum);
-
-       if (actual_error) {
-               g_propagate_error (error, actual_error);
-       }
-}
-
 static void
 cache_create_service_decomposed (TrackerData  *data,
                                  TrackerClass *cl)
@@ -2444,57 +2354,6 @@ delete_all_objects (TrackerData  *data,
        }
 }
 
-static gboolean
-tracker_data_insert_statement_common (TrackerData  *data,
-                                      const gchar  *graph,
-                                      const gchar  *subject,
-                                      const gchar  *predicate,
-                                      const gchar  *object,
-                                      GError      **error)
-{
-       if (g_str_has_prefix (subject, ":")) {
-               /* blank node definition
-                  pile up statements until the end of the blank node */
-               gchar *value;
-               GError *actual_error = NULL;
-
-               if (data->blank_buffer.subject != NULL) {
-                       /* active subject in buffer */
-                       if (strcmp (data->blank_buffer.subject, subject) != 0) {
-                               /* subject changed, need to flush buffer */
-                               tracker_data_blank_buffer_flush (data, &actual_error);
-
-                               if (actual_error) {
-                                       g_propagate_error (error, actual_error);
-                                       return FALSE;
-                               }
-                       }
-               }
-
-               if (data->blank_buffer.subject == NULL) {
-                       data->blank_buffer.subject = g_strdup (subject);
-                       if (data->blank_buffer.graphs == NULL) {
-                               data->blank_buffer.graphs = g_array_sized_new (FALSE, FALSE, sizeof (char*), 
4);
-                               data->blank_buffer.predicates = g_array_sized_new (FALSE, FALSE, sizeof 
(char*), 4);
-                               data->blank_buffer.objects = g_array_sized_new (FALSE, FALSE, sizeof (char*), 
4);
-                       }
-               }
-
-               value = g_strdup (graph);
-               g_array_append_val (data->blank_buffer.graphs, value);
-               value = g_strdup (predicate);
-               g_array_append_val (data->blank_buffer.predicates, value);
-               value = g_strdup (object);
-               g_array_append_val (data->blank_buffer.objects, value);
-
-               return FALSE;
-       }
-
-       resource_buffer_switch (data, graph, subject, 0);
-
-       return TRUE;
-}
-
 void
 tracker_data_insert_statement (TrackerData  *data,
                                const gchar  *graph,
@@ -2526,57 +2385,6 @@ tracker_data_insert_statement (TrackerData  *data,
        }
 }
 
-
-static gboolean
-handle_blank_node (TrackerData  *data,
-                   const gchar  *subject,
-                   const gchar  *predicate,
-                   const gchar  *object,
-                   const gchar  *graph,
-                   gboolean      update,
-                   GError      **error)
-{
-       GError *actual_error = NULL;
-       /* anonymous blank node used as object in a statement */
-       const gchar *blank_uri;
-
-       if (data->blank_buffer.subject != NULL) {
-               if (strcmp (data->blank_buffer.subject, object) == 0) {
-                       /* object still in blank buffer, need to flush buffer */
-                       tracker_data_blank_buffer_flush (data, &actual_error);
-
-                       if (actual_error) {
-                               g_propagate_error (error, actual_error);
-                               return FALSE;
-                       }
-               }
-       }
-
-       blank_uri = g_hash_table_lookup (data->blank_buffer.table, object);
-
-       if (blank_uri != NULL) {
-               /* now insert statement referring to blank node */
-               if (update) {
-                       tracker_data_update_statement (data, graph, subject, predicate, blank_uri, 
&actual_error);
-               } else {
-                       tracker_data_insert_statement (data, graph, subject, predicate, blank_uri, 
&actual_error);
-               }
-
-               g_hash_table_remove (data->blank_buffer.table, object);
-
-               if (actual_error) {
-                       g_propagate_error (error, actual_error);
-                       return FALSE;
-               }
-
-               return TRUE;
-       } else {
-               g_critical ("Blank node '%s' not found", object);
-
-               return FALSE;
-       }
-}
-
 void
 tracker_data_insert_statement_with_uri (TrackerData  *data,
                                         const gchar  *graph,
@@ -2618,26 +2426,7 @@ tracker_data_insert_statement_with_uri (TrackerData  *data,
 
        data->has_persistent = TRUE;
 
-       /* subjects and objects starting with `:' are anonymous blank nodes */
-       if (g_str_has_prefix (object, ":")) {
-               if (handle_blank_node (data, subject, predicate, object, graph, FALSE, &actual_error)) {
-                       return;
-               }
-
-               if (actual_error) {
-                       g_propagate_error (error, actual_error);
-                       return;
-               }
-       }
-
-       if (!tracker_data_insert_statement_common (data, graph, subject, predicate, object, &actual_error)) {
-               if (actual_error) {
-                       g_propagate_error (error, actual_error);
-                       return;
-               }
-
-               return;
-       }
+       resource_buffer_switch (data, graph, subject, 0);
 
        if (graph)
                graph_id = tracker_data_manager_find_graph (data->manager, graph);
@@ -2735,14 +2524,7 @@ tracker_data_insert_statement_with_string (TrackerData  *data,
 
        data->has_persistent = TRUE;
 
-       if (!tracker_data_insert_statement_common (data, graph, subject, predicate, object, &actual_error)) {
-               if (actual_error) {
-                       g_propagate_error (error, actual_error);
-                       return;
-               }
-
-               return;
-       }
+       resource_buffer_switch (data, graph, subject, 0);
 
        if (graph)
                graph_id = tracker_data_manager_find_graph (data->manager, graph);
@@ -2818,27 +2600,7 @@ tracker_data_update_statement_with_uri (TrackerData  *data,
 
        data->has_persistent = TRUE;
 
-       /* subjects and objects starting with `:' are anonymous blank nodes */
-       if (g_str_has_prefix (object, ":")) {
-               if (handle_blank_node (data, subject, predicate, object, graph, TRUE, &actual_error)) {
-                       return;
-               }
-
-               if (actual_error) {
-                       g_propagate_error (error, actual_error);
-                       return;
-               }
-       }
-
-       /* Update and insert share the exact same code here */
-       if (!tracker_data_insert_statement_common (data, graph, subject, predicate, object, &actual_error)) {
-               if (actual_error) {
-                       g_propagate_error (error, actual_error);
-                       return;
-               }
-
-               return;
-       }
+       resource_buffer_switch (data, graph, subject, 0);
 
        if (graph)
                graph_id = tracker_data_manager_find_graph (data->manager, graph);
@@ -3026,15 +2788,7 @@ tracker_data_update_statement_with_string (TrackerData  *data,
 
        data->has_persistent = TRUE;
 
-       /* Update and insert share the exact same code here */
-       if (!tracker_data_insert_statement_common (data, graph, subject, predicate, object, &actual_error)) {
-               if (actual_error) {
-                       g_propagate_error (error, actual_error);
-                       return;
-               }
-
-               return;
-       }
+       resource_buffer_switch (data, graph, subject, 0);
 
 #if HAVE_TRACKER_FTS
        /* This is unavoidable with FTS */
@@ -3191,9 +2945,6 @@ tracker_data_begin_transaction (TrackerData  *data,
        }
 
        data->resource_buffer = NULL;
-       if (data->blank_buffer.table == NULL) {
-               data->blank_buffer.table = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);
-       }
 
        iface = tracker_data_manager_get_writable_db_interface (data->manager);