glib-genmarshal

glib-genmarshal glib-genmarshal — C code marshaller generation utility for GLib closures

Synopsis

glib-genmarshal [options...] [files...]

Description

glib-genmarshal is a small utility that generates C code marshallers for callback functions of the GClosure mechanism in the GObject sublibrary of GLib. The marshaller functions have a standard signature, they get passed in the invoking closure, an array of value structures holding the callback function parameters and a value structure for the return value of the callback. The marshaller is then responsible to call the respective C code function of the closure with all the parameters on the stack and to collect its return value.

Invocation

glib-genmarshal takes a list of marshallers to generate as input. The marshaller list is either read from standard input or from files passed as additional arguments on the command line.

Options

--header	Generate header file contents of the marshallers.
--body	Generate C code file contents of the marshallers.
--prefix=string, --prefix string	Specify marshaller prefix. The default prefix is `g_cclosure_marshal'.
--skip-source	Skip source location remarks in generated comments.
--nostdinc	Do not use the standard marshallers of the GObject library, and skip gmarshal.h include directive in generated header files.
--g-fatal-warnings	Make warnings fatal, that is, exit immediately once a warning occurs.
-h, --help	Print brief help and exit.
-v, --version	Print version and exit.

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Marshaller list format

The marshaller lists are processed line by line, a line can contain a comment in the form of

# this is a comment

or a marshaller specification of the form

RTYPE:PTYPE
RTYPE:PTYPE,PTYPE
RTYPE:PTYPE,PTYPE,PTYPE

(up to 16 PTYPEs may be present).

The RTYPE part specifies the callback's return type and the PTYPEs right to the colon specify the callback's parameter list, except for the first and the last arguments which are always pointers.

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Parameter types

Currently, the following types are supported:

VOID	indicates no return type, or no extra parameters. If VOID is used as the parameter list, no additional parameters may be present.
BOOLEAN	for boolean types (gboolean)
CHAR	for signed char types (gchar)
UCHAR	for unsigned char types (guchar)
INT	for signed integer types (gint)
UINT	for unsigned integer types (guint)
LONG	for signed long integer types (glong)
ULONG	for unsigned long integer types (gulong)
INT64	for signed 64bit integer types (gint64)
UINT64	for unsigned 64bit integer types (guint64)
ENUM	for enumeration types (gint)
FLAGS	for flag enumeration types (guint)
FLOAT	for single-precision float types (gfloat)
DOUBLE	for double-precision float types (gdouble)
STRING	for string types (gchar*)
BOXED	for boxed (anonymous but reference counted) types (GBoxed*)
PARAM	for GParamSpec or derived types (GParamSpec*)
POINTER	for anonymous pointer types (gpointer)
OBJECT	for GObject or derived types (GObject*)
NONE	deprecated alias for VOID
BOOL	deprecated alias for BOOLEAN

Example

To generate marshallers for the following callback functions:

void   foo (gpointer data1,
            gpointer data2);
void   bar (gpointer data1,
            gint     param1,
            gpointer data2);
gfloat baz (gpointer data1,
            gboolean param1,
            guchar   param2,
            gpointer data2);

The marshaller list has to look like this:

VOID:VOID
VOID:INT
FLOAT:BOOLEAN,UCHAR

The generated marshallers have the arguments encoded in their function name. For this particular list, they are

g_cclosure_marshal_VOID__VOID(),
g_cclosure_marshal_VOID__INT(), 
g_cclosure_marshal_FLOAT__BOOLEAN_UCHAR().

They can be used directly for GClosures or be passed in as the GSignalCMarshaller c_marshaller; argument upon creation of signals:

GClosure *cc_foo, *cc_bar, *cc_baz;

cc_foo = g_cclosure_new (NULL, foo, NULL);
g_closure_set_marshal (cc_foo, g_cclosure_marshal_VOID__VOID);
cc_bar = g_cclosure_new (NULL, bar, NULL);
g_closure_set_marshal (cc_bar, g_cclosure_marshal_VOID__INT);
cc_baz = g_cclosure_new (NULL, baz, NULL);
g_closure_set_marshal (cc_baz, g_cclosure_marshal_FLOAT__BOOLEAN_UCHAR);