[tracker: 3/5] libtracker-sparql: Solve signed vs unsigned pointer warnings

[Carlos Garnacho <carlosg src gnome org>]

commit 7b58c3f7aa952811df4406a368372d2a078da153
Author: Daniele Nicolodi <daniele grinta net>
Date:   Thu May 6 13:37:37 2021 +0200

    libtracker-sparql: Solve signed vs unsigned pointer warnings
    
    libxml2 functions 'const xmlChar *' (aka 'unsigned char *') type for
    strings arguments however literals in C are of type 'char *'.  This
    results in warnings about the conversion between pointers of different
    size. Add a macro to perform the type casts required to silence the
    warnings in a more descriptive and less ugly way.

 src/libtracker-sparql/tracker-serializer-xml.c | 27 ++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)
---
diff --git a/src/libtracker-sparql/tracker-serializer-xml.c b/src/libtracker-sparql/tracker-serializer-xml.c
index a722809bd..d2b66f83b 100644
--- a/src/libtracker-sparql/tracker-serializer-xml.c
+++ b/src/libtracker-sparql/tracker-serializer-xml.c
@@ -29,6 +29,9 @@
 
 #include <libxml/xmlwriter.h>
 
+/* Make required type casts a bit more descriptive. */
+#define XML(x) ((const xmlChar *) x)
+
 struct _TrackerSerializerXml
 {
        TrackerSerializer parent_instance;
@@ -75,15 +78,15 @@ serialize_up_to_position (TrackerSerializerXml  *serializer_xml,
 
        if (!serializer_xml->head_printed) {
                xmlTextWriterStartDocument (serializer_xml->writer, "1.0", "UTF-8", NULL);
-               xmlTextWriterStartElement (serializer_xml->writer, "sparql");
+               xmlTextWriterStartElement (serializer_xml->writer, XML ("sparql"));
 
-               xmlTextWriterStartElement (serializer_xml->writer, "head");
+               xmlTextWriterStartElement (serializer_xml->writer, XML ("head"));
 
                for (i = 0; i < tracker_sparql_cursor_get_n_columns (cursor); i++) {
                        const gchar *var;
 
                        var = tracker_sparql_cursor_get_variable_name (cursor, i);
-                       xmlTextWriterStartElement (serializer_xml->writer, "variable");
+                       xmlTextWriterStartElement (serializer_xml->writer, XML ("variable"));
 
                        if (var && *var) {
                                g_ptr_array_add (serializer_xml->vars,
@@ -94,14 +97,14 @@ serialize_up_to_position (TrackerSerializerXml  *serializer_xml,
                        }
 
                        xmlTextWriterWriteFormatAttribute (serializer_xml->writer,
-                                                          "name",
+                                                          XML ("name"),
                                                           "%s",
-                                                          (gchar *) g_ptr_array_index (serializer_xml->vars, 
i));
+                                                          g_ptr_array_index (serializer_xml->vars, i));
                        xmlTextWriterEndElement (serializer_xml->writer);
                }
 
                xmlTextWriterEndElement (serializer_xml->writer);
-               xmlTextWriterStartElement (serializer_xml->writer, "results");
+               xmlTextWriterStartElement (serializer_xml->writer, XML ("results"));
                serializer_xml->head_printed = TRUE;
        }
 
@@ -122,7 +125,7 @@ serialize_up_to_position (TrackerSerializerXml  *serializer_xml,
                        serializer_xml->cursor_started = TRUE;
                }
 
-               xmlTextWriterStartElement (serializer_xml->writer, "result");
+               xmlTextWriterStartElement (serializer_xml->writer, XML ("result"));
 
                for (i = 0; i < tracker_sparql_cursor_get_n_columns (cursor); i++) {
                        const gchar *var, *str, *type = NULL, *datatype = NULL;
@@ -157,17 +160,17 @@ serialize_up_to_position (TrackerSerializerXml  *serializer_xml,
 
                        var = g_ptr_array_index (serializer_xml->vars, i);
 
-                       xmlTextWriterStartElement (serializer_xml->writer, "binding");
+                       xmlTextWriterStartElement (serializer_xml->writer, XML ("binding"));
                        xmlTextWriterWriteFormatAttribute (serializer_xml->writer,
-                                                          "name",
+                                                          XML ("name"),
                                                           "%s",
                                                           var);
 
-                       xmlTextWriterStartElement (serializer_xml->writer, type);
+                       xmlTextWriterStartElement (serializer_xml->writer, XML (type));
 
                        if (datatype) {
                                xmlTextWriterWriteFormatAttribute (serializer_xml->writer,
-                                                                  "datatype",
+                                                                  XML ("datatype"),
                                                                   "%s",
                                                                   datatype);
                        }
@@ -175,7 +178,7 @@ serialize_up_to_position (TrackerSerializerXml  *serializer_xml,
                        str = tracker_sparql_cursor_get_string (cursor, i, NULL);
 
                        if (str) {
-                               xmlTextWriterWriteRaw (serializer_xml->writer, str);
+                               xmlTextWriterWriteRaw (serializer_xml->writer, XML (str));
                        }
 
                        xmlTextWriterEndElement (serializer_xml->writer);