Tribblix: manual page: dbus-binding-tool.1

dbus-binding-tool(1) User Commands dbus-binding-tool(1)

NAME

dbus-binding-tool - C language dbus-glib bindings generation utility.

SYNOPSIS

dbus-binding-tool [--force] [--help] [--ignore-unsupported]
[--mode=pretty|glib-client|glib-server] [--output=file]
[--prefix=symbol-prefix] [--version] [file...]

DESCRIPTION

dbus-binding-tool is used to expose a GObject via D-Bus, using the
deprecated dbus-glib binding for GLib. As input, dbus-binding-tool
uses a D-Bus Introspection XML file. As output, the client-side or
server-side bindings is generated. This output is a header file
which eases the use of a remote D-Bus object. Output is sent to
standard out or to the filename specified with the --output argument.

EXTENDED DESCRIPTION

The following is a sample D-Bus Introspection XML file which
describes an object that exposes one method, named ManyArgs:

<?xml version="1.0" encoding="UTF-8" ?>
<node name="/com/example/MyObject">
<interface name="com.example.MyObject">
<method name="ManyArgs">
<arg type="u" name="x" direction="in" />
<arg type="s" name="str" direction="in" />
<arg type="d" name="trouble" direction="in" />
<arg type="d" name="d_ret" direction="out" />
<arg type="s" name="str_ret" direction="out" />
</method>
</interface>
</node>

dbus-binding-tool supports annotations in the XML format to further
control how the bindings are generated.

client-side bindings
When building client-side bindings, the --mode=glib-client argument
is used. The client-side bindings support the
"org.freedesktop.DBus.Glib.NoReply" annotation. This is specified
within the <method> tag to indicate that the client is not expecting
a reply to the method call, so a reply should not be sent. This is
often used to speed up rapid method calls where there are no "out"
arguments, and not knowing if the method succeeded is an acceptable
compromise to halve the traffic on the bus. For example:

<method name "FooMethod">
[...]
<annotation name="org.freedesktop.DBus.GLib.NoReply" value="yes"/>
[...]
</method>

server-side bindings
When building server-side bindings, the --mode=glib-server argument
is used. Also the --prefix argument must be used when building
server-side bindings so that functions in the generated output are
prefexed with the specified value. The server-side bindings support
the following annotations:

"org.freedesktop.DBus.GLib.CSymbol"

This annotation is used to specify the C symbol names for the various
types (interface, method, etc.), if it differs from the name D-Bus
generates.

<interface name="com.example.MyObject">
<annotation name="org.freedesktop.DBus.GLib.CSymbol" value="my_object"/>
[...]
<method name "ManyArgs">
<annotation name="org.freedesktop.DBus.GLib.CSymbol" value="my_object_many_args"/>
[...]
</method>
</interface>

"org.freedesktop.DBus.GLib.Async"

This annotation marks the method implementation as an asynchronous
function, which does not return a response straight away but will
send the response at some later point to complete the call. This is
used to implement non-blocking services where method calls can take
time.

When a method is asynchronous, the function prototype is different.
It is required that the function conform to the following rules:

+o
The function must return a value of type gboolean; TRUE on
success, and FALSE otherwise.
+o
The first parameter is a pointer to an instance of the object.
+o
Following the object instance pointer are the method input
values.
+o
The final parameter must be a (DBusGMethodInvocation *). This is
used when sending the response message back to the client, by
calling dbus_g_method_return or dbus_g_method_return_error.

For example:

<method name "FooMethod">
[...]
<annotation name="org.freedesktop.DBus.GLib.Async" value="yes"/>
[...]
</method>

"org.freedesktop.DBus.GLib.Const"

This attribute can only be applied to "out" <arg> nodes, and
specifies that the parameter is not being copied when returned. For
example, this turns a 's' argument from a (char **) to a (const char
**), and results in the argument not being freed by D-Bus after the
message is sent. For example:

<arg type="u" name="x" direction="out">
<annotation name="org.freedesktop.DBus.GLib.Const" value=""/>
</arg>

"org.freedesktop.DBus.GLib.ReturnVal"

This attribute can only be applied to "out" <arg> nodes, and alters
the expected function signature. It currently can be set to two
values: "" or "error". The argument marked with this attribute is not
returned via a pointer argument, but by the function's return value.
If the attribute's value is the empty string, the (GError *) argument
is also omitted so there is no standard way to return an error value.
This is very useful for interfacing with existing code, as it is
possible to match existing APIs. If the attribute's value is "error",
then the final argument is a (GError *) as usual. For example:

<arg type="u" name="x" direction="out">
<annotation name="org.freedesktop.DBus.GLib.ReturnVal" value=""/>
</arg>

OPTIONS

The following options are supported:

--force

Overwrite the output file if it already exists with a newer
timestamp than the source files.

--help

Display usage information.

--ignore-unsupported

If set, then unsupported signatures for <method> parameters are
ignored.

--mode=pretty|glib-client|glib-server

If the value is "glib-client", then client bindings are
generated. If the value is "glib-server", then server bindings
are generated. If the value is "pretty", then the output is in a
more human readable format.

--output=file

Specify the output file.

--prefix=symbol-prefix

Functions in the generated output are prefixed with the symbol-
prefix value.

--version

Display the version number of the dbus-binding-tool command.

OPERANDS

The following operands are supported:

file
A list of one or more input D-Bus Introspection XML
files to include in the generated output.

FILES

The following files are used by this application:

${exec_prefix}/bin/dbus-binding-tool
Executable for the D-Bus Binding Tool
application.

NOTES

dbus-binding-tool is part of dbus-glib, which is a deprecated D-Bus
binding for GLib.

dbus-glib receives minimal maintenance and security fixes for the
benefit of projects like Telepathy and NetworkManager that still rely
on it, but should not be used in new projects (and existing projects
should try to move away from it, too). Please use GDBus, part of GLib
since 2.26.

gdbus-codegen(1) is the GDBus replacement for dbus-binding-tool.

AUTHORS

Man page written by Brian Cameron, Sun Microsystems Inc., 2009.

dbus-glib 0.112 8 Oct 2018 dbus-binding-tool(1)