[gtk-doc] scangobj: Avoid generating unused params

[Stefan Sauer <stefkost src gnome org>]

commit e39e5f87cb9157a6991ae72c7a7ea014f6df7a02
Author: Pavel Grunt <pavelgrunt gmail com>
Date:   Sun Oct 29 10:07:23 2017 +0100

    scangobj: Avoid generating unused params
    
    The main function params may be unused depending on type init function
    definition. That may lead to generating a warning about unused in a
    project using gtk-doc, eg:
        DOC   Scanning header files
        DOC   Introspecting gobjects
      spice-gtk-scan.c: In function ‘main’:
      spice-gtk-scan.c:126:11: warning: unused parameter ‘argc’ [-Wunused-parameter]
       main (int argc, char *argv[])
               ^~~~
      spice-gtk-scan.c:126:23: warning: unused parameter ‘argv’ [-Wunused-parameter]
       main (int argc, char *argv[])
    
    Check for the presence of argc and argv in the type init function
    and generate main function params accordingly
    
    https://bugzilla.gnome.org/show_bug.cgi?id=773879

 gtkdoc/scangobj.py |   10 +++++++++-
 1 files changed, 9 insertions(+), 1 deletions(-)
---
diff --git a/gtkdoc/scangobj.py b/gtkdoc/scangobj.py
index 116270a..235a851 100644
--- a/gtkdoc/scangobj.py
+++ b/gtkdoc/scangobj.py
@@ -125,7 +125,7 @@ static void output_args (void);
 static void output_object_args (FILE *fp, GType object_type);
 
 int
-main (int argc, char *argv[])
+main (${main_func_params})
 {
   ${type_init_func};
 
@@ -1229,6 +1229,14 @@ def run(options):
 
     # substitute local vars in the template
     type_init_func = options.type_init_func
+    main_func_params = "int argc, char *argv[]"
+    if "argc" in type_init_func and "argv" not in type_init_func:
+        main_func_params = "int argc, G_GNUC_UNUSED char *argv[]"
+    elif "argc" not in type_init_func and "argv" in type_init_func:
+        main_func_params = "G_GNUC_UNUSED int argc, char *argv[]"
+    elif "argc" not in type_init_func and "argv" not in type_init_func:
+        main_func_params = "void"
+
     output.write(string.Template(MAIN_CODE).substitute(locals()))
 
     if options.query_child_properties: