/**
* Obtains the machine UUID of the machine this process is running on.
*
* The returned string must be freed with dbus_free().
*
* This UUID is guaranteed to remain the same until the next reboot
* (unless the sysadmin foolishly changes it and screws themselves).
* It will usually remain the same across reboots also, but hardware
* configuration changes or rebuilding the machine could break that.
*
* The idea is that two processes with the same machine ID should be
* able to use shared memory, UNIX domain sockets, process IDs, and other
* features of the OS that require both processes to be running
* on the same OS kernel instance.
*
* The machine ID can also be used to create unique per-machine
* instances. For example, you could use it in bus names or
* X selection names.
*
* The machine ID is preferred over the machine hostname, because
* the hostname is frequently set to "localhost.localdomain" and
* may also change at runtime.
*
* You can get the machine ID of a remote application by invoking the
* method GetMachineId from interface org.freedesktop.DBus.Peer.
*
* If the remote application has the same machine ID as the one
* returned by this function, then the remote application is on the
* same machine as your application.
*
* The UUID is not a UUID in the sense of RFC4122; the details
* are explained in the D-Bus specification.
*
* @returns a 32-byte-long hex-encoded UUID string, or #NULL if insufficient memory
*/
char*
dbus_get_local_machine_id (void)
{
DBusString uuid;
char *s;
s = NULL;
if (!_dbus_string_init (&uuid))
return NULL;
/* The documentation says dbus_get_local_machine_id() only fails on OOM;
* this can actually also fail if the D-Bus installation is faulty
* (no UUID) *and* reading a new random UUID fails, but we have no way
* to report that */
if (!_dbus_get_local_machine_uuid_encoded (&uuid, NULL) ||
!_dbus_string_steal_data (&uuid, &s))
{
_dbus_string_free (&uuid);
return NULL;
}
else
{
_dbus_string_free (&uuid);
return s;
}
}
/**
* Obtains the machine UUID of the machine this process is running on.
*
* The returned string must be freed with dbus_free().
*
* This UUID is guaranteed to remain the same until the next reboot
* (unless the sysadmin foolishly changes it and screws themselves).
* It will usually remain the same across reboots also, but hardware
* configuration changes or rebuilding the machine could break that.
*
* The idea is that two processes with the same machine ID should be
* able to use shared memory, UNIX domain sockets, process IDs, and other
* features of the OS that require both processes to be running
* on the same OS kernel instance.
*
* The machine ID can also be used to create unique per-machine
* instances. For example, you could use it in bus names or
* X selection names.
*
* The machine ID is preferred over the machine hostname, because
* the hostname is frequently set to "localhost.localdomain" and
* may also change at runtime.
*
* You can get the machine ID of a remote application by invoking the
* method GetMachineId from interface org.freedesktop.DBus.Peer.
*
* If the remote application has the same machine ID as the one
* returned by this function, then the remote application is on the
* same machine as your application.
*
* The UUID is not a UUID in the sense of RFC4122; the details
* are explained in the D-Bus specification.
*
* @returns a 32-byte-long hex-encoded UUID string, or #NULL if insufficient memory
*/
char*
dbus_get_local_machine_id (void)
{
DBusString uuid;
char *s;
s = NULL;
if (!_dbus_string_init (&uuid))
return NULL;
if (!_dbus_get_local_machine_uuid_encoded (&uuid) ||
!_dbus_string_steal_data (&uuid, &s))
{
_dbus_string_free (&uuid);
return NULL;
}
else
{
_dbus_string_free (&uuid);
return s;
}
}
