m2-GTK4/tools

tools — GIR → Modula-2 binding generator

gir2def.py is the optional, broad-coverage companion to the hand-written bindings in src/. It reads a GObject-Introspection .gir file and emits DEFINITION MODULE FOR "C" .def files that link straight against the C library.

Usage

make gir                       # Gtk-4.0 -> gen/
make gir GIR=Gio-2.0           # another namespace
make gir-check                 # generate + parse all + compile/link a sample
make gir-verify                # check every identifier exists in the .so

# or directly
python3 tools/gir2def.py Gtk-4.0 -o gen
python3 tools/gir2def.py Adw-1 -o gen
python3 tools/gir_verify.py Adw-1 --gir-dir /usr/share/gir-1.0

.gir files ship with the introspection data, typically /usr/share/gir-1.0/<Namespace>-<Version>.gir.

Output goes to gen/ (git-ignored). Generated files are meant to be reviewed and cherry-picked, not to replace src/.

What it produces

For Gtk-4.0 it currently emits 301 type modules, 3719 procedures and 750 enum constants; for GLib-2.0, Gio-2.0 and Adw-1, 77 / 168 / 83 modules. Every emitted module parses under gm2 -fiso (make gir-check, which bulk-imports all of them and links a sample), and make gir-verify confirms every identifier exists in the installed library:

namespace	identifiers	unexpected missing
Gtk-4.0	3719	0
GLib-2.0	1825	0
Gio-2.0	1870	0
Adw-1	1188	0

gir_verify.py strips symbol-version suffixes (@@LIBADWAITA_1_0) and consults gir_verify_allowlist.txt, which lists the handful of GIR entries that are macros, deprecated no-ops or per-module ABI functions rather than exported symbols.

• One module per class/interface/record/boxed, named <Namespace><Name> (GtkButton, ...), with a TYPE <C type> = ADDRESS; alias.
• Constructors, methods and functions from that type. The procedure name is the GIR c:identifier, so no name mangling is needed.
• Namespace-level functions in <Namespace>Functions.def.
• Enumerations and bitfields in <Namespace>Enums.def, named by their c:identifier (e.g. GTK_ALIGN_FILL).

Example (gen/GtkButton.def):

DEFINITION MODULE FOR "C" GtkButton ;

FROM SYSTEM IMPORT ADDRESS;

EXPORT UNQUALIFIED
   GtkButton, gtk_button_new, gtk_button_new_with_label,
   gtk_button_get_label, gtk_button_set_label;

TYPE
   GtkButton = ADDRESS;

PROCEDURE gtk_button_new () : [ ADDRESS ];
PROCEDURE gtk_button_new_with_label (label: ARRAY OF CHAR) : [ ADDRESS ];
PROCEDURE gtk_button_get_label (button: GtkButton) : [ ADDRESS ];
PROCEDURE gtk_button_set_label (button: GtkButton; label: ARRAY OF CHAR);

END GtkButton.

Type mapping

GIR	Modula-2
gboolean, gint*, int, gshort	INTEGER
guint*, unsigned int, gunichar	CARDINAL
glong, gint64, gssize, goffset	LONGINT
gulong, guint64, gsize, GType	LONGCARD
gchar, guchar	CHAR
gfloat, float	SHORTREAL
gdouble, double	REAL
utf8 / filename (in)	ARRAY OF CHAR
utf8 / filename (out, return)	ADDRESS
enumeration / bitfield	CARDINAL
arrays, pointers, callbacks, unknown	ADDRESS
out / inout scalar	VAR <type>

Return values are always emitted as ignorable, : [ T ].

Limits (why it is a starting point, not a re-placement)

• Value structs (by-value records such as GdkRGBA) become opaque ADDRESS; only pointer semantics are correct.
• Signals, properties, and GObject class/interface hierarchies are not emitted.
• Variadic functions and GError ** parameters are dropped.
• Callbacks are ADDRESS; use them with GtkClosures.Connect3 by hand.
• Constructors return ADDRESS for foreign types, so you may want to hand-edit those to the owning type name.
• No [ ]/VAR heuristics beyond the ones above.

The hand-written modules in src/ remain the idiomatic API; the generator is there to bootstrap areas not covered by hand.