gdbstub: Use g_markup_printf_escaped()

g_markup_printf_escaped() is a safer alternative to simple printf() as
it automatically escapes values.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-Id: <20230912224107.29669-9-akihiko.odaki@daynix.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231009164104.369749-16-alex.bennee@linaro.org>

gdbstub/gdbstub.c

@@ -373,28 +373,34 @@ static const char *get_feature_xml(const char *p, const char **newp,
     if (strncmp(p, "target.xml", len) == 0) {
         if (!process->target_xml) {
             GDBRegisterState *r;
-            GString *xml = g_string_new("<?xml version=\"1.0\"?>");
+            g_autoptr(GPtrArray) xml = g_ptr_array_new_with_free_func(g_free);
 
-            g_string_append(xml,
-                            "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">"
-                            "<target>");
+            g_ptr_array_add(
+                xml,
+                g_strdup("<?xml version=\"1.0\"?>"
+                         "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">"
+                         "<target>"));
 
             if (cc->gdb_arch_name) {
-                g_string_append_printf(xml,
-                                       "<architecture>%s</architecture>",
-                                       cc->gdb_arch_name(cpu));
+                g_ptr_array_add(
+                    xml,
+                    g_markup_printf_escaped("<architecture>%s</architecture>",
+                                            cc->gdb_arch_name(cpu)));
             }
-            g_string_append(xml, "<xi:include href=\"");
-            g_string_append(xml, cc->gdb_core_xml_file);
-            g_string_append(xml, "\"/>");
+            g_ptr_array_add(
+                xml,
+                g_markup_printf_escaped("<xi:include href=\"%s\"/>",
+                                        cc->gdb_core_xml_file));
             for (r = cpu->gdb_regs; r; r = r->next) {
-                g_string_append(xml, "<xi:include href=\"");
-                g_string_append(xml, r->xml);
-                g_string_append(xml, "\"/>");
+                g_ptr_array_add(
+                    xml,
+                    g_markup_printf_escaped("<xi:include href=\"%s\"/>",
+                                            r->xml));
             }
-            g_string_append(xml, "</target>");
+            g_ptr_array_add(xml, g_strdup("</target>"));
+            g_ptr_array_add(xml, NULL);
 
-            process->target_xml = g_string_free(xml, false);
+            process->target_xml = g_strjoinv(NULL, (void *)xml->pdata);
         }
         return process->target_xml;
     }