[tracker/return-types: 3/26] libtracker-data: Store types of query results

[Martyn James Russell <mr src gnome org>]

commit 87b3f0d6d952e13d4adaabcad1ec36653a4fbb80
Author: Jürg Billeter <j bitron ch>
Date:   Wed Sep 8 18:36:24 2010 +0200

    libtracker-data: Store types of query results

 src/libtracker-data/libtracker-data.vapi          |    2 +-
 src/libtracker-data/tracker-db-interface-sqlite.c |   49 ++++++++++++++++----
 src/libtracker-data/tracker-db-interface.h        |    6 +++
 src/libtracker-data/tracker-sparql-pattern.vala   |    2 +
 src/libtracker-data/tracker-sparql-query.vala     |   19 +++++---
 5 files changed, 60 insertions(+), 18 deletions(-)
---
diff --git a/src/libtracker-data/libtracker-data.vapi b/src/libtracker-data/libtracker-data.vapi
index b74c3d5..4bdef4f 100644
--- a/src/libtracker-data/libtracker-data.vapi
+++ b/src/libtracker-data/libtracker-data.vapi
@@ -72,7 +72,7 @@ namespace Tracker {
 		public abstract void bind_int (int index, int value);
 		public abstract void bind_text (int index, string value);
 		public abstract DBResultSet execute () throws DBInterfaceError;
-		public abstract DBCursor start_cursor () throws DBInterfaceError;
+		public abstract DBCursor start_sparql_cursor (PropertyType[] types) throws DBInterfaceError;
 	}
 
 	[CCode (cheader_filename = "libtracker-data/tracker-class.h")]
diff --git a/src/libtracker-data/tracker-db-interface-sqlite.c b/src/libtracker-data/tracker-db-interface-sqlite.c
index 48de5ec..b87aa78 100644
--- a/src/libtracker-data/tracker-db-interface-sqlite.c
+++ b/src/libtracker-data/tracker-db-interface-sqlite.c
@@ -71,6 +71,8 @@ struct TrackerDBCursor {
 	TrackerDBStatement *ref_stmt;
 	gboolean finished;
 	gchar **variable_names;
+	TrackerPropertyType *types;
+	gint n_types;
 };
 
 struct TrackerDBCursorClass {
@@ -88,14 +90,16 @@ struct TrackerDBStatementClass {
 	GObjectClass parent_class;
 };
 
-static TrackerDBStatement     * tracker_db_statement_sqlite_new   (TrackerDBInterface     *db_interface,
-                                                                   sqlite3_stmt           *sqlite_stmt);
-static TrackerDBCursor        * tracker_db_cursor_sqlite_new      (sqlite3_stmt           *sqlite_stmt,
-                                                                   TrackerDBStatement     *ref_stmt);
-static void                     tracker_db_statement_sqlite_reset (TrackerDBStatement     *stmt);
-static gboolean                 db_cursor_iter_next               (TrackerDBCursor        *cursor,
-                                                                   GCancellable           *cancellable,
-                                                                   GError                **error);
+static TrackerDBStatement *tracker_db_statement_sqlite_new   (TrackerDBInterface   *db_interface,
+                                                              sqlite3_stmt         *sqlite_stmt);
+static TrackerDBCursor    *tracker_db_cursor_sqlite_new      (sqlite3_stmt         *sqlite_stmt,
+                                                              TrackerDBStatement   *ref_stmt,
+                                                              TrackerPropertyType  *types,
+                                                              gint                  n_types);
+static void                tracker_db_statement_sqlite_reset (TrackerDBStatement   *stmt);
+static gboolean            db_cursor_iter_next               (TrackerDBCursor      *cursor,
+                                                              GCancellable         *cancellable,
+                                                              GError              **error);
 
 enum {
 	PROP_0,
@@ -1090,6 +1094,8 @@ tracker_db_cursor_finalize (GObject *object)
 
 	cursor = TRACKER_DB_CURSOR (object);
 
+	g_free (cursor->types);
+
 	g_strfreev (cursor->variable_names);
 	cursor->variable_names = NULL;
 
@@ -1188,7 +1194,9 @@ tracker_db_cursor_class_init (TrackerDBCursorClass *class)
 
 static TrackerDBCursor *
 tracker_db_cursor_sqlite_new (sqlite3_stmt              *sqlite_stmt,
-                              TrackerDBStatement        *ref_stmt)
+                              TrackerDBStatement        *ref_stmt,
+                              TrackerPropertyType       *types,
+                              gint                       n_types)
 {
 	TrackerDBCursor *cursor;
 
@@ -1204,6 +1212,16 @@ tracker_db_cursor_sqlite_new (sqlite3_stmt              *sqlite_stmt,
 		cursor->ref_stmt = NULL;
 	}
 
+	if (types) {
+		gint i;
+
+		cursor->types = g_new (TrackerPropertyType, n_types);
+		cursor->n_types = n_types;
+		for (i = 0; i < n_types; i++) {
+			cursor->types[i] = types[i];
+		}
+	}
+
 	return cursor;
 }
 
@@ -1427,7 +1445,18 @@ tracker_db_statement_start_cursor (TrackerDBStatement             *stmt,
 {
 	g_return_val_if_fail (!stmt->stmt_is_sunk, NULL);
 
-	return tracker_db_cursor_sqlite_new (stmt->stmt, stmt);
+	return tracker_db_cursor_sqlite_new (stmt->stmt, stmt, NULL, 0);
+}
+
+TrackerDBCursor *
+tracker_db_statement_start_sparql_cursor (TrackerDBStatement             *stmt,
+                                          TrackerPropertyType            *types,
+                                          gint                            n_types,
+                                          GError                        **error)
+{
+	g_return_val_if_fail (!stmt->stmt_is_sunk, NULL);
+
+	return tracker_db_cursor_sqlite_new (stmt->stmt, stmt, types, n_types);
 }
 
 
diff --git a/src/libtracker-data/tracker-db-interface.h b/src/libtracker-data/tracker-db-interface.h
index ecf1275..d63e1b1 100644
--- a/src/libtracker-data/tracker-db-interface.h
+++ b/src/libtracker-data/tracker-db-interface.h
@@ -25,6 +25,8 @@
 
 #include <libtracker-sparql/tracker-sparql.h>
 
+#include "tracker-property.h"
+
 G_BEGIN_DECLS
 
 #if !defined (__LIBTRACKER_DATA_INSIDE__) && !defined (TRACKER_COMPILATION)
@@ -115,6 +117,10 @@ TrackerDBResultSet *    tracker_db_statement_execute            (TrackerDBStatem
                                                                  GError             **error);
 TrackerDBCursor *       tracker_db_statement_start_cursor       (TrackerDBStatement  *stmt,
                                                                  GError             **error);
+TrackerDBCursor *       tracker_db_statement_start_sparql_cursor(TrackerDBStatement  *stmt,
+                                                                 TrackerPropertyType *types,
+                                                                 gint                 n_types,
+                                                                 GError             **error);
 
 /* Semi private TrackerDBResultSet functions */
 TrackerDBResultSet *    _tracker_db_result_set_new              (guint                cols);
diff --git a/src/libtracker-data/tracker-sparql-pattern.vala b/src/libtracker-data/tracker-sparql-pattern.vala
index bbc5aeb..aef222f 100644
--- a/src/libtracker-data/tracker-sparql-pattern.vala
+++ b/src/libtracker-data/tracker-sparql-pattern.vala
@@ -296,6 +296,7 @@ class Tracker.Sparql.Pattern : Object {
 				} else {
 					Expression.append_expression_as_string (sql, variable.sql_expression, variable.binding.data_type);
 				}
+				result.types += variable.binding.data_type;
 			}
 		} else {
 			while (true) {
@@ -306,6 +307,7 @@ class Tracker.Sparql.Pattern : Object {
 				}
 
 				type = expression.translate_select_expression (sql, subquery);
+				result.types += type;
 
 				switch (current ()) {
 				case SparqlTokenType.FROM:
diff --git a/src/libtracker-data/tracker-sparql-query.vala b/src/libtracker-data/tracker-sparql-query.vala
index a68eba4..4238a10 100644
--- a/src/libtracker-data/tracker-sparql-query.vala
+++ b/src/libtracker-data/tracker-sparql-query.vala
@@ -158,6 +158,7 @@ namespace Tracker.Sparql {
 
 	class SelectContext : Context {
 		public PropertyType type;
+		public PropertyType[] types = {};
 
 		public SelectContext (Context? parent_context = null) {
 			base (parent_context);
@@ -517,18 +518,18 @@ public class Tracker.Sparql.Query : Object {
 		return stmt.execute ();
 	}
 
-	DBCursor? exec_sql_cursor (string sql) throws DBInterfaceError, Sparql.Error, DateError {
+	DBCursor? exec_sql_cursor (string sql, PropertyType[] types) throws DBInterfaceError, Sparql.Error, DateError {
 		var stmt = prepare_for_exec (sql);
 
-		return stmt.start_cursor ();
+		return stmt.start_sparql_cursor (types);
 	}
 
-	string get_select_query () throws DBInterfaceError, Sparql.Error, DateError {
+	string get_select_query (out SelectContext context) throws DBInterfaceError, Sparql.Error, DateError {
 		// SELECT query
 
 		// build SQL
 		var sql = new StringBuilder ();
-		pattern.translate_select (sql);
+		context = pattern.translate_select (sql);
 
 		expect (SparqlTokenType.EOF);
 
@@ -536,11 +537,15 @@ public class Tracker.Sparql.Query : Object {
 	}
 
 	DBResultSet? execute_select () throws DBInterfaceError, Sparql.Error, DateError {
-		return exec_sql (get_select_query ());
+		SelectContext context;
+		return exec_sql (get_select_query (out context));
 	}
 
 	DBCursor? execute_select_cursor () throws DBInterfaceError, Sparql.Error, DateError {
-		return exec_sql_cursor (get_select_query ());
+		SelectContext context;
+		string sql = get_select_query (out context);
+
+		return exec_sql_cursor (sql, context.types);
 	}
 
 	string get_ask_query () throws DBInterfaceError, Sparql.Error, DateError {
@@ -575,7 +580,7 @@ public class Tracker.Sparql.Query : Object {
 	}
 
 	DBCursor? execute_ask_cursor () throws DBInterfaceError, Sparql.Error, DateError {
-		return exec_sql_cursor (get_ask_query ());
+		return exec_sql_cursor (get_ask_query (), new PropertyType[] { PropertyType.BOOLEAN });
 	}
 
 	private void parse_from_or_into_param () throws Sparql.Error {