Initialize an xkbdeviceledinforec structure
XkbDeviceLedInfoPtr XkbAddDeviceLedInfo (\^XkbDeviceInfoPtr device_info\^, unsigned int led_class\^, unsigned int led_id\^);
- device_info
structure in which to add LED info
- led_class
input extension class for LED device of interest
- led_id
input extension ID for LED device of interest
XkbAddDeviceLedInfo first checks to see whether an entry matching led_class and led_id already exists in the device_info->leds array. If it finds a matching entry, it returns a pointer to that entry. Otherwise, it checks to be sure there is at least one empty entry in device_info->leds and extends it if there is not enough room. It then increments device_info->num_leds and fills in the next available entry in device_info->leds with led_class and led_id.
If successful, XkbAddDeviceLedInfo returns a pointer to the XkbDeviceLedInfoRec structure that was initialized. If unable to allocate sufficient storage, or if device_info points to an invalid XkbDeviceInfoRec structure, or if led_class or led_id are inappropriate, XkbAddDeviceLedInfo returns NULL.
To allocate additional space for button actions in an XkbDeviceInfoRec structure, use XkbResizeDeviceButtonActions.
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;