XkbFreeDeviceInfo − Free an XkbDeviceInfoRec structure


void XkbFreeDeviceInfo

(XkbDeviceInfoPtr device_info, unsigned int

which, Bool free_all);


− device_info

pointer to XkbDeviceInfoRec in which to free items

− which

mask of components of device_info to free

− free_all

True => free everything, including device_info


If free_all is True, the XkbFreeDeviceInfo frees all components of device_info and the XkbDeviceInfoRec structure pointed to by device_info itself. If free_all is False, the value of which determines which subcomponents are freed. which is an inclusive OR of one or more of the values from Table 1. If which contains XkbXI_ButtonActionsMask, all button actions associated with device_info are freed, device_info->btn_acts is set to NULL, and device_info->num_btns is set to zero. If which contains all bits in XkbXI_IndicatorsMask, all XkbDeviceLedInfoRec structures associated with device_info are freed, device_info->leds is set to NULL, and device_info->sz_leds and device_info->num_leds are set to zero. If which contains XkbXI_IndicatorMapsMask, all indicator maps associated with device_info are cleared, but the number of LEDs and the leds structures themselves is preserved. If which contains XkbXI_IndicatorNamesMask, all indicator names associated with device_info are cleared, but the number of LEDs and the leds structures themselves is preserved. If which contains XkbXI_IndicatorStateMask, the indicator state associated with the device_info leds are set to zeros but the number of LEDs and the leds structures themselves is preserved.

Table 1 XkbDeviceInfoRec Mask Bits
Name XkbDeviceInfoRec Value Capability If Set
Fields Effected
XkbXI_KeyboardsMask (1L <<0) Clients can use all
Xkb requests and events
with KeyClass devices
supported by the input
device extension.

XkbXI_ButtonActionsMask num_btns (1L <<1) Clients can assign key
btn_acts actions to buttons
non-KeyClass input
extension devices.

XkbXI_IndicatorNamesMask leds->names (1L <<2) Clients can assign
names to indicators on
non-KeyClass input
extension devices.

XkbXI_IndicatorMapsMask leds->maps (1L <<3) Clients can assign
indicator maps to
indicators on
non-KeyClass input
extension devices.

XkbXI_IndicatorStateMask leds->state (1L <<4) Clients can request
the status of indicators
on non-KeyClass input
extension devices.

XkbXI_IndicatorsMask sz_leds (0x1c) XkbXI_IndicatorNamesMask |
num_leds XkbXI_IndicatorMapsMask |
leds->* XkbXI_IndicatorStateMask

XkbXI_UnsupportedFeaturesMask unsupported (1L <<15)

XkbXI_AllDeviceFeaturesMask Those selected (0x1e) XkbXI_IndicatorsMask |
by Value Column XkbSI_ButtonActionsMask

XkbXI_AllFeaturesMask Those selected (0x1f) XkbSI_AllDeviceFeaturesMask |
by Value Column XkbSI_KeyboardsMask

XkbXI_AllDetailsMask Those selected (0x801f) XkbXI_AllFeaturesMask |
by Value column XkbXI_UnsupportedFeaturesMask


Information about X Input Extension devices is transferred between a client program and the Xkb extension in an XkbDeviceInfoRec structure:

typedef struct {
char * name; /∗ name for device */
Atom type; /∗ name for class of devices */
unsigned short device_spec; /∗ device of interest */
Bool has_own_state; /∗ True=>this device has its own state */
unsigned short supported; /∗ bits indicating supported capabilities */
unsigned short unsupported; /∗ bits indicating unsupported capabilities */
unsigned short num_btns; /∗ number of entries in btn_acts */
XkbAction * btn_acts; /∗ button actions */
unsigned short sz_leds; /∗ total number of entries in LEDs vector */
unsigned short num_leds; /∗ number of valid entries in LEDs vector */
unsigned short dflt_kbd_fb; /∗ input extension ID of default (core kbd) indicator */
unsigned short dflt_led_fb; /∗ input extension ID of default indicator feedback */
XkbDeviceLedInfoPtr leds; /∗ LED descriptions */
} XkbDeviceInfoRec, *XkbDeviceInfoPtr;

typedef struct {
unsigned short led_class; /∗ class for this LED device*/
unsigned short led_id; /∗ ID for this LED device */
unsigned int phys_indicators; /∗ bits for which LEDs physically present */
unsigned int maps_present; /∗ bits for which LEDs have maps in maps */
unsigned int names_present; /∗ bits for which LEDs are in names */
unsigned int state; /∗ 1 bit => corresponding LED is on */
Atom names[XkbNumIndicators]; /∗ names for LEDs */
XkbIndicatorMapRec maps; /∗ indicator maps for each LED */
} XkbDeviceLedInfoRec, *XkbDeviceLedInfoPtr;


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