gergelypolonkai-web-jekyll/_posts/2014-08-16-registering-an-enum-type-in-glib-glib-mkenums-magic.markdown

layout	title	date	tags	permalink	published	author
post	Registering an enum type in GLib, glib-mkenums magic	2014-08-16 15:10:54+00:00	development c glib	/blog/2014/8/16/registering-an-enum-type-in-glib-glib-mkenums-magic	true	name email Gergely Polonkai gergely@polonkai.eu

In this post I said I will get through the GLib Makefiles to add an enum type to GLib in a more sophisticated way.

In my other project, SWE-GLib I already used this method. The following two rules in Makefile.am create gswe-enumtypes.h and gswe-enumtypes.c.

{% highlight make %} gswe-enumtypes.h: $(gswe_enum_headers) gswe-enumtypes.h.template $(GLIB_MKENUMS) --template $(filter %.template,$^) $(filter-out %.template,$^) >
gswe-enumtypes.h.tmp && mv gswe-enumtypes.h.tmp gswe-enumtypes.h gswe-enumtypes.c: $(gswe_enum_headers) gswe-enumtypes.h gswe-enumtypes.c.template $(GLIB_MKENUMS) --template $(filter %.template,$^) $(filter-out %.template,$^) >
gswe-enumtypes.c.tmp && mv gswe-enumtypes.c.tmp gswe-enumtypes.c {% endhighlight %}

$(GLIB_MKENUMS) is set in configure with AC_PATH_PROG([GLIB_MKENUMS], [glib-mkenums]).

This approach requires the GNU Autotools (you can get rid of it by changing $(GLIB_MKENUMS) to the path to glib-mkenums binary), and two template files, one for the header and one for the code. $(gswe_enum_headers) contains a list of all the header files that have enum types defined throughout the project.

{% highlight c %} /*** BEGIN file-header **/ / gswe-enumtypes.h - Enumeration types for SWE-GLib *

• Copyright © 2013 Gergely Polonkai
• SWE-GLib is free software: you can redistribute it and/or modify
• it under the terms of the GNU General Public License as published by
• the Free Software Foundation; either version 3 of the License, or
• (at your option) any later version.
• SWE-GLib is distributed in the hope that it will be useful,
• but WITHOUT ANY WARRANTY; without even the implied warranty of
• MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
• GNU General Public License for more details.
• You should have received a copy of the GNU General Public License
• along with this library; if not, see http://www.gnu.org/licenses/. */ #ifndef GSWE_ENUM_TYPES_H #define GSWE_ENUM_TYPES_H #include <glib-object.h>

/*** END file-header ***/

/*** BEGIN file-production **/ / enumerations from "@filename@" */

#include "@filename@" /*** END file-production ***/

/*** BEGIN value-header / GType @enum_name@_get_type(void); #define @ENUMPREFIX@TYPE@ENUMSHORT@ (@enum_name@_get_type()) / END value-header ***/

/*** BEGIN file-tail ***/

#endif /* GSWE_ENUM_TYPES_H / /** END file-tail ***/ {% endhighlight %}

{% highlight c %} /*** BEGIN file-header **/ / gswe-enumtypes.c - Enumeration types for SWE-GLib *

• Copyright © 2013 Gergely Polonkai
• SWE-GLib is free software: you can redistribute it and/or modify
• it under the terms of the GNU General Public License as published by
• the Free Software Foundation; either version 3 of the License, or
• (at your option) any later version.
• SWE-GLib is distributed in the hope that it will be useful,
• but WITHOUT ANY WARRANTY; without even the implied warranty of
• MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
• GNU General Public License for more details.
• You should have received a copy of the GNU General Public License
• along with this library; if not, see http://www.gnu.org/licenses/. */ #include "swe-glib.h" #include "gswe-enumtypes.h" #include "@filename@"

/*** END file-header ***/

/*** BEGIN file-production / / enumerations from "@filename@" / / END file-production ***/

/*** BEGIN value-header ***/ GType @enum_name@_get_type(void) { static volatile gsize g_define_type_id__volatile = 0;

gswe_init();

if (g_once_init_enter(&g;_define_type_id__volatile)) {
    static const G@Type@Value values[] = {

/*** END value-header ***/

/*** BEGIN value-production / { @VALUENAME@, "@VALUENAME@", "@valuenick@" }, / END value-production ***/

/*** BEGIN value-tail ***/ { 0, NULL, NULL } };

    GType g_define_type_id = g_@type@_register_static(
            g_intern_static_string("@EnumName@"),
            values
        );

    g_once_init_leave(&g;_define_type_id__volatile, g_define_type_id);
}

return g_define_type_id__volatile;

}

/*** END value-tail ***/ {% endhighlight %}