[libgda] Misc GdaConnection corrections

[Vivien Malerba <vivien src gnome org>]

commit 11185b3a6b82aa06f8335d9a2ff5a492b4efe24c
Author: Vivien Malerba <malerba gnome-db org>
Date:   Wed Nov 19 18:21:36 2014 +0100

    Misc GdaConnection corrections

 libgda/gda-connection.c |   16 ++++++++++++++--
 1 files changed, 14 insertions(+), 2 deletions(-)
---
diff --git a/libgda/gda-connection.c b/libgda/gda-connection.c
index 4a57a81..1ba095d 100644
--- a/libgda/gda-connection.c
+++ b/libgda/gda-connection.c
@@ -73,6 +73,7 @@
 #include <glib/gstdio.h>
 #include <fcntl.h>
 #include <unistd.h>
+#include <ctype.h>
 
 static GMutex global_mutex;
 static GdaSqlParser *internal_parser = NULL;
@@ -1437,6 +1438,7 @@ gda_connection_open_async (GdaConnection *cnc, GdaConnectionOpenFunc callback, g
        if (gda_connection_is_opened (cnc)) {
                g_set_error (error, GDA_CONNECTION_ERROR, GDA_CONNECTION_ALREADY_OPENED_ERROR,
                             "%s", _("Connection is alreay opened"));
+               return 0;
        }
 
        GdaQuarkList *params, *auth;
@@ -3036,6 +3038,7 @@ gda_connection_statement_execute_v (GdaConnection *cnc, GdaStatement *stmt, GdaS
        }
 
        g_object_unref ((GObject*) cnc);
+
        if (timer)
                g_timer_destroy (timer);
 
@@ -3063,10 +3066,19 @@ gda_connection_execute_select_command (GdaConnection *cnc, const gchar *sql, GEr
 
        g_return_val_if_fail (sql != NULL
                              || GDA_IS_CONNECTION (cnc)
-                             || !gda_connection_is_opened (cnc)
-                             || g_str_has_prefix (sql, "SELECT"),
+                             || !gda_connection_is_opened (cnc),
                              NULL);
 
+       while (isspace (*sql))
+               sql++;
+       g_return_val_if_fail (((sql[0] == 'S') || (sql[0] == 's')) &&
+                             ((sql[1] == 'E') || (sql[1] == 'e')) &&
+                             ((sql[2] == 'L') || (sql[2] == 'l')) &&
+                             ((sql[3] == 'E') || (sql[3] == 'e')) &&
+                             ((sql[4] == 'C') || (sql[4] == 'c')) &&
+                             ((sql[5] == 'T') || (sql[5] == 't')) &&
+                             isspace (sql[6]), NULL);
+
        g_mutex_lock (&global_mutex);
        if (!internal_parser)
                internal_parser = gda_sql_parser_new ();