xref: /xsrc/external/mit/xorg-server.old/dist/xkb/xkbLEDs.c

/************************************************************
Copyright (c) 1995 by Silicon Graphics Computer Systems, Inc.

Permission to use, copy, modify, and distribute this
software and its documentation for any purpose and without
fee is hereby granted, provided that the above copyright
notice appear in all copies and that both that copyright
notice and this permission notice appear in supporting
documentation, and that the name of Silicon Graphics not be
used in advertising or publicity pertaining to distribution
of the software without specific prior written permission.
Silicon Graphics makes no representation about the suitability
of this software for any purpose. It is provided "as is"
without any express or implied warranty.

SILICON GRAPHICS DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON
GRAPHICS BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL
DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION  WITH
THE USE OR PERFORMANCE OF THIS SOFTWARE.

********************************************************/

#ifdef HAVE_DIX_CONFIG_H
#include <dix-config.h>
#endif

#include <stdio.h>
#include <ctype.h>
#include <math.h>
#include <X11/X.h>
#include <X11/Xproto.h>
#include "misc.h"
#include "inputstr.h"

#include <X11/extensions/XI.h>
#include <xkbsrv.h>
#include "xkb.h"

/***====================================================================***/

	/*
	 * unsigned
	 * XkbIndicatorsToUpdate(dev,changed,check_devs_rtrn)
	 *
	 * Given a keyboard and a set of state components that have changed,
	 * this function returns the indicators on the default keyboard
	 * feedback that might be affected.   It also reports whether or not
	 * any extension devices might be affected in check_devs_rtrn.
	 */

unsigned
XkbIndicatorsToUpdate(	DeviceIntPtr	dev,
			unsigned long 	state_changes,
			Bool		enable_changes)
{
register unsigned	update=	0;
XkbSrvLedInfoPtr	sli;

    sli= XkbFindSrvLedInfo(dev,XkbDfltXIClass,XkbDfltXIId,0);

    if (!sli)
        return update;

    if (state_changes&(XkbModifierStateMask|XkbGroupStateMask))
	update|= sli->usesEffective;
    if (state_changes&(XkbModifierBaseMask|XkbGroupBaseMask))
	update|= sli->usesBase;
    if (state_changes&(XkbModifierLatchMask|XkbGroupLatchMask))
	update|= sli->usesLatched;
    if (state_changes&(XkbModifierLockMask|XkbGroupLockMask))
	update|= sli->usesLocked;
    if (state_changes&XkbCompatStateMask)
	update|= sli->usesCompat;
    if (enable_changes)
	update|= sli->usesControls;
    return update;
}

/***====================================================================***/

	/*
	 * Bool
	 *XkbApplyLEDChangeToKeyboard(xkbi,map,on,change)
	 *
	 * Some indicators "drive" the keyboard when their state is explicitly
	 * changed, as described in section 9.2.1 of the XKB protocol spec.
	 * This function updates the state and controls for the keyboard
	 * specified by 'xkbi' to reflect any changes that are required
	 * when the indicator described by 'map' is turned on or off.  The
	 * extent of the changes is reported in change, which must be defined.
	 */
static Bool
XkbApplyLEDChangeToKeyboard(	XkbSrvInfoPtr		xkbi,
				XkbIndicatorMapPtr	map,
				Bool			on,
				XkbChangesPtr		change)
{
Bool		ctrlChange,stateChange;
XkbStatePtr	state;

    if ((map->flags&XkbIM_NoExplicit)||((map->flags&XkbIM_LEDDrivesKB)==0))
	return FALSE;
    ctrlChange= stateChange= FALSE;
    if (map->ctrls) {
	XkbControlsPtr	ctrls= xkbi->desc->ctrls;
	unsigned 	old;

	old= ctrls->enabled_ctrls;
	if (on)	ctrls->enabled_ctrls|= map->ctrls;
	else	ctrls->enabled_ctrls&= ~map->ctrls;
	if (old!=ctrls->enabled_ctrls) {
	    change->ctrls.changed_ctrls= XkbControlsEnabledMask;
	    change->ctrls.enabled_ctrls_changes= old^ctrls->enabled_ctrls;
	    ctrlChange= TRUE;
	}
    }
    state= &xkbi->state;
    if ((map->groups)&&((map->which_groups&(~XkbIM_UseBase))!=0)) {
	register int i;
	register unsigned bit,match;

	if (on)	match= (map->groups)&XkbAllGroupsMask;
	else 	match= (~map->groups)&XkbAllGroupsMask;
	if (map->which_groups&(XkbIM_UseLocked|XkbIM_UseEffective)) {
	    for (i=0,bit=1;i<XkbNumKbdGroups;i++,bit<<=1) {
		if (bit&match)
		    break;
	    }
	    if (map->which_groups&XkbIM_UseLatched)
		XkbLatchGroup(xkbi->device,0); /* unlatch group */
	    state->locked_group= i;
	    stateChange= TRUE;
	}
	else if (map->which_groups&(XkbIM_UseLatched|XkbIM_UseEffective)) {
	    for (i=0,bit=1;i<XkbNumKbdGroups;i++,bit<<=1) {
		if (bit&match)
		    break;
	    }
	    state->locked_group= 0;
	    XkbLatchGroup(xkbi->device,i);
	    stateChange= TRUE;
	}
    }
    if ((map->mods.mask)&&((map->which_mods&(~XkbIM_UseBase))!=0)) {
	if (map->which_mods&(XkbIM_UseLocked|XkbIM_UseEffective)) {
	    register unsigned long old;
	    old= state->locked_mods;
	    if (on)	state->locked_mods|= map->mods.mask;
	    else	state->locked_mods&= ~map->mods.mask;
	    if (state->locked_mods!=old)
		stateChange= TRUE;
	}
	if (map->which_mods&(XkbIM_UseLatched|XkbIM_UseEffective)) {
	    register unsigned long newmods;
	    newmods= state->latched_mods;
	    if (on)	newmods|=  map->mods.mask;
	    else	newmods&= ~map->mods.mask;
	    if (newmods!=state->locked_mods) {
		newmods&= map->mods.mask;
		XkbLatchModifiers(xkbi->device,map->mods.mask,newmods);
		stateChange= TRUE;
	    }
	}
    }
    return stateChange || ctrlChange;
}

	/*
	 * Bool
	 * ComputeAutoState(map,state,ctrls)
	 *
	 * This function reports the effect of applying the specified
	 * indicator map given the specified state and controls, as
	 * described in section 9.2 of the XKB protocol specification.
	 */

static Bool
ComputeAutoState(	XkbIndicatorMapPtr	map,
			XkbStatePtr 		state,
			XkbControlsPtr 		ctrls)
{
Bool 			on;
CARD8 			mods,group;

    on= FALSE;
    mods= group= 0;
    if (map->which_mods&XkbIM_UseAnyMods) {
	if (map->which_mods&XkbIM_UseBase)
	    mods|= state->base_mods;
	if (map->which_mods&XkbIM_UseLatched)
	    mods|= state->latched_mods;
	if (map->which_mods&XkbIM_UseLocked)
	    mods|= state->locked_mods;
	if (map->which_mods&XkbIM_UseEffective)
	    mods|= state->mods;
	if (map->which_mods&XkbIM_UseCompat)
	    mods|= state->compat_state;
	on = ((map->mods.mask&mods)!=0);
	on = on||((mods==0)&&(map->mods.mask==0)&&(map->mods.vmods==0));
    }
    if (map->which_groups&XkbIM_UseAnyGroup) {
	if (map->which_groups&XkbIM_UseBase)
	    group|= (1L << state->base_group);
	if (map->which_groups&XkbIM_UseLatched)
	    group|= (1L << state->latched_group);
	if (map->which_groups&XkbIM_UseLocked)
	    group|= (1L << state->locked_group);
	if (map->which_groups&XkbIM_UseEffective)
	    group|= (1L << state->group);
	on = on||(((map->groups&group)!=0)||(map->groups==0));
    }
    if (map->ctrls)
	on = on||(ctrls->enabled_ctrls&map->ctrls);
    return on;
}


static void
XkbUpdateLedAutoState(	DeviceIntPtr			dev,
			XkbSrvLedInfoPtr		sli,
			unsigned			maps_to_check,
			xkbExtensionDeviceNotify *	ed,
			XkbChangesPtr			changes,
			XkbEventCausePtr		cause)
{
DeviceIntPtr			kbd;
XkbStatePtr			state;
XkbControlsPtr			ctrls;
XkbChangesRec			my_changes;
xkbExtensionDeviceNotify	my_ed;
register unsigned		i,bit,affected;
register XkbIndicatorMapPtr	map;
unsigned			oldState;

    if ((maps_to_check==0)||(sli->maps==NULL)||(sli->mapsPresent==0))
	return;

    if (dev->key && dev->key->xkbInfo)
	 kbd= dev;
    else kbd= inputInfo.keyboard;

    state= &kbd->key->xkbInfo->state;
    ctrls= kbd->key->xkbInfo->desc->ctrls;
    affected= maps_to_check;
    oldState= sli->effectiveState;
    sli->autoState&= ~affected;
    for (i=0,bit=1;(i<XkbNumIndicators)&&(affected);i++,bit<<=1) {
	if ((affected&bit)==0)
	    continue;
	affected&= ~bit;
	map= &sli->maps[i];
	if((!(map->flags&XkbIM_NoAutomatic))&&ComputeAutoState(map,state,ctrls))
	    sli->autoState|= bit;
    }
    sli->effectiveState= (sli->autoState|sli->explicitState);
    affected= sli->effectiveState^oldState;
    if (affected==0)
	return;

    if (ed==NULL) {
	ed= &my_ed;
	memset((char *)ed, 0, sizeof(xkbExtensionDeviceNotify));
    }
    else if ((ed->reason&XkbXI_IndicatorsMask)&&
	     ((ed->ledClass!=sli->class)||(ed->ledID!=sli->id))) {
	XkbFlushLedEvents(dev,kbd,sli,ed,changes,cause);
    }

    if ((kbd==dev)&&(sli->flags&XkbSLI_IsDefault)) {
	if (changes==NULL) {
	    changes= &my_changes;
	    memset((char *)changes, 0, sizeof(XkbChangesRec));
	}
	changes->indicators.state_changes|= affected;
    }

    ed->reason|=	XkbXI_IndicatorStateMask;
    ed->ledClass= 	sli->class;
    ed->ledID=		sli->id;
    ed->ledsDefined=	sli->namesPresent|sli->mapsPresent;
    ed->ledState=	sli->effectiveState;
    ed->unsupported=	0;
    ed->supported=	XkbXI_AllFeaturesMask;

    if (changes!=&my_changes)	changes= NULL;
    if (ed!=&my_ed)		ed= NULL;
    if (changes || ed)
	XkbFlushLedEvents(dev,kbd,sli,ed,changes,cause);
    return;
}

static void
XkbUpdateAllDeviceIndicators(XkbChangesPtr changes,XkbEventCausePtr cause)
{
DeviceIntPtr		edev;
XkbSrvLedInfoPtr	sli;

    for (edev=inputInfo.devices;edev!=NULL;edev=edev->next) {
	if (edev->kbdfeed) {
	    KbdFeedbackPtr	kf;
	    for (kf=edev->kbdfeed;kf!=NULL;kf=kf->next) {
		if ((kf->xkb_sli==NULL)||(kf->xkb_sli->maps==NULL))
		    continue;
		sli= kf->xkb_sli;
		XkbUpdateLedAutoState(edev,sli,sli->mapsPresent,NULL,
								changes,cause);

	    }
	}
	if (edev->leds) {
	    LedFeedbackPtr	lf;
	    for (lf=edev->leds;lf!=NULL;lf=lf->next) {
		if ((lf->xkb_sli==NULL)||(lf->xkb_sli->maps==NULL))
		    continue;
		sli= lf->xkb_sli;
		XkbUpdateLedAutoState(edev,sli,sli->mapsPresent,NULL,
								changes,cause);

	    }
	}
    }
    return;
}


/***====================================================================***/

	/*
	 * void
	 * XkbSetIndicators(dev,affect,values,cause)
	 *
	 * Attempts to change the indicators specified in 'affect' to the
	 * states specified in 'values' for the default keyboard feedback
	 * on the keyboard specified by 'dev.'   Attempts to change indicator
	 * state might be ignored or have no affect, depending on the XKB
	 * indicator map for any affected indicators, as described in section
	 * 9.2 of the XKB protocol specification.
	 *
	 * If 'changes' is non-NULL, this function notes any changes to the
	 * keyboard state, controls, or indicator state that result from this
	 * attempted change.   If 'changes' is NULL, this function generates
	 * XKB events to report any such changes to interested clients.
	 *
	 * If 'cause' is non-NULL, it specifies the reason for the change,
	 * as reported in some XKB events.   If it is NULL, this function
	 * assumes that the change is the result of a core protocol
	 * ChangeKeyboardMapping request.
	 */

void
XkbSetIndicators(	DeviceIntPtr		dev,
			CARD32			affect,
			CARD32			values,
			XkbEventCausePtr	cause)
{
XkbSrvLedInfoPtr		sli;
XkbChangesRec			changes;
xkbExtensionDeviceNotify	ed;
unsigned 			side_affected;

    memset((char *)&changes, 0, sizeof(XkbChangesRec));
    memset((char *)&ed, 0, sizeof(xkbExtensionDeviceNotify));
    sli= XkbFindSrvLedInfo(dev,XkbDfltXIClass,XkbDfltXIId,0);
    sli->explicitState&= ~affect;
    sli->explicitState|= (affect&values);
    XkbApplyLedStateChanges(dev,sli,affect,&ed,&changes,cause);

    side_affected= 0;
    if (changes.state_changes!=0)
	side_affected|= XkbIndicatorsToUpdate(dev,changes.state_changes,FALSE);
    if (changes.ctrls.enabled_ctrls_changes)
	side_affected|= sli->usesControls;

    if (side_affected) {
	XkbUpdateLedAutoState(dev,sli,side_affected,&ed,&changes,cause);
	affect|= side_affected;
    }
    if (changes.state_changes || changes.ctrls.enabled_ctrls_changes)
	XkbUpdateAllDeviceIndicators(NULL,cause);

    XkbFlushLedEvents(dev,dev,sli,&ed,&changes,cause);
    return;
}

/***====================================================================***/

/***====================================================================***/

	/*
	 * void
	 * XkbUpdateIndicators(dev,update,check_edevs,changes,cause)
	 *
	 * Applies the indicator maps for any indicators specified in
	 * 'update' from the default keyboard feedback on the device
	 * specified by 'dev.'
	 *
	 * If 'changes' is NULL, this function generates and XKB events
	 * required to report the necessary changes, otherwise it simply
	 * notes the indicators with changed state.
	 *
	 * If 'check_edevs' is TRUE, this function also checks the indicator
	 * maps for any open extension devices that have them, and updates
	 * the state of any extension device indicators as necessary.
	 */

void
XkbUpdateIndicators(	DeviceIntPtr		dev,
			register CARD32		update,
			Bool			check_edevs,
			XkbChangesPtr		changes,
			XkbEventCausePtr	cause)
{
XkbSrvLedInfoPtr	sli;

    sli= XkbFindSrvLedInfo(dev,XkbDfltXIClass,XkbDfltXIId,0);
    XkbUpdateLedAutoState(dev,sli,update,NULL,changes,cause);
    if (check_edevs)
	XkbUpdateAllDeviceIndicators(changes,cause);
    return;
}

/***====================================================================***/

/***====================================================================***/

	/*
	 * void
	 * XkbCheckIndicatorMaps(dev,sli,which)
	 *
	 * Updates the 'indicator accelerators' for the indicators specified
	 * by 'which' in the feedback specified by 'sli.' The indicator
	 * accelerators are internal to the server and are used to simplify
	 * and speed up the process of figuring out which indicators might
	 * be affected by a particular change in keyboard state or controls.
	 */

void
XkbCheckIndicatorMaps(DeviceIntPtr dev,XkbSrvLedInfoPtr sli,unsigned which)
{
register unsigned	i,bit;
XkbIndicatorMapPtr	map;
XkbDescPtr		xkb;

    if ((sli->flags&XkbSLI_HasOwnState)==0)
        return;

    sli->usesBase&=	 ~which;
    sli->usesLatched&=	 ~which;
    sli->usesLocked&=	 ~which;
    sli->usesEffective&= ~which;
    sli->usesCompat&=	 ~which;
    sli->usesControls&=	 ~which;
    sli->mapsPresent&=	 ~which;

    xkb= dev->key->xkbInfo->desc;
    for (i=0,bit=1,map=sli->maps;i<XkbNumIndicators;i++,bit<<=1,map++) {
	if (which&bit) {
	    CARD8		what;

	    if (!map || !XkbIM_InUse(map))
		continue;
	    sli->mapsPresent|= bit;

	    what= (map->which_mods|map->which_groups);
	    if (what&XkbIM_UseBase)
		 sli->usesBase|= bit;
	    if (what&XkbIM_UseLatched)
		 sli->usesLatched|= bit;
	    if (what&XkbIM_UseLocked)
		 sli->usesLocked|= bit;
	    if (what&XkbIM_UseEffective)
		 sli->usesEffective|= bit;
	    if (what&XkbIM_UseCompat)
		 sli->usesCompat|= bit;
	    if (map->ctrls)
		 sli->usesControls|= bit;

	    map->mods.mask= map->mods.real_mods;
	    if (map->mods.vmods!=0) {
		map->mods.mask|= XkbMaskForVMask(xkb,map->mods.vmods);
	    }
	}
    }
    sli->usedComponents= 0;
    if (sli->usesBase)
	sli->usedComponents|= XkbModifierBaseMask|XkbGroupBaseMask;
    if (sli->usesLatched)
	sli->usedComponents|= XkbModifierLatchMask|XkbGroupLatchMask;
    if (sli->usesLocked)
	sli->usedComponents|= XkbModifierLockMask|XkbGroupLockMask;
    if (sli->usesEffective)
	sli->usedComponents|= XkbModifierStateMask|XkbGroupStateMask;
    if (sli->usesCompat)
	sli->usedComponents|= XkbCompatStateMask;
    return;
}

/***====================================================================***/

	/*
	 * XkbSrvLedInfoPtr
	 * XkbAllocSrvLedInfo(dev,kf,lf,needed_parts)
	 *
	 * Allocates an XkbSrvLedInfoPtr for the feedback specified by either
	 * 'kf' or 'lf' on the keyboard specified by 'dev.'
	 *
	 * If 'needed_parts' is non-zero, this function makes sure that any
	 * of the parts speicified therein are allocated.
	 */
XkbSrvLedInfoPtr
XkbAllocSrvLedInfo(	DeviceIntPtr		dev,
			KbdFeedbackPtr		kf,
			LedFeedbackPtr		lf,
			unsigned		needed_parts)
{
XkbSrvLedInfoPtr	sli;
Bool			checkAccel;
Bool			checkNames;

    sli= NULL;
    checkAccel= checkNames= FALSE;
    if ((kf!=NULL)&&(kf->xkb_sli==NULL)) {
	kf->xkb_sli= sli= calloc(1, sizeof(XkbSrvLedInfoRec));
	if (sli==NULL)
	    return NULL; /* ALLOCATION ERROR */
	if (dev->key && dev->key->xkbInfo)
	     sli->flags= XkbSLI_HasOwnState;
	else sli->flags= 0;
	sli->class=	KbdFeedbackClass;
	sli->id=	kf->ctrl.id;
	sli->fb.kf=	kf;

	sli->autoState=		0;
	sli->explicitState=	kf->ctrl.leds;
	sli->effectiveState=	kf->ctrl.leds;

	if ((kf==dev->kbdfeed) && (dev->key) && (dev->key->xkbInfo)) {
	    XkbDescPtr	xkb;
	    xkb= dev->key->xkbInfo->desc;
	    sli->flags|= 		XkbSLI_IsDefault;
	    sli->physIndicators=	xkb->indicators->phys_indicators;
	    sli->names=			xkb->names->indicators;
	    sli->maps=			xkb->indicators->maps;
	    checkNames= checkAccel=	TRUE;
	}
	else {
	    sli->physIndicators=	XkbAllIndicatorsMask;
	    sli->names=			NULL;
	    sli->maps=			NULL;
	}
    }
    else if ((kf!=NULL)&&((kf->xkb_sli->flags&XkbSLI_IsDefault)!=0)) {
	XkbDescPtr	xkb;
	xkb= dev->key->xkbInfo->desc;
	sli= kf->xkb_sli;
	sli->physIndicators=	xkb->indicators->phys_indicators;
	if (xkb->names->indicators!=sli->names) {
	    checkNames= TRUE;
	    sli->names= xkb->names->indicators;
	}
	if (xkb->indicators->maps!=sli->maps) {
	    checkAccel= TRUE;
	    sli->maps= xkb->indicators->maps;
	}
    }
    else if ((lf!=NULL)&&(lf->xkb_sli==NULL)) {
	lf->xkb_sli= sli= calloc(1, sizeof(XkbSrvLedInfoRec));
	if (sli==NULL)
	    return NULL; /* ALLOCATION ERROR */
	if (dev->key && dev->key->xkbInfo)
	     sli->flags= XkbSLI_HasOwnState;
	else sli->flags= 0;
	sli->class=	LedFeedbackClass;
	sli->id=	lf->ctrl.id;
	sli->fb.lf=	lf;

	sli->physIndicators=	lf->ctrl.led_mask;
	sli->autoState=		0;
	sli->explicitState=	lf->ctrl.led_values;
	sli->effectiveState=	lf->ctrl.led_values;
	sli->maps=		NULL;
	sli->names=		NULL;
    }
    else
	return NULL;
    if ((sli->names==NULL)&&(needed_parts&XkbXI_IndicatorNamesMask))
	sli->names= calloc(XkbNumIndicators, sizeof(Atom));
    if ((sli->maps==NULL)&&(needed_parts&XkbXI_IndicatorMapsMask))
	sli->maps= calloc(XkbNumIndicators, sizeof(XkbIndicatorMapRec));
    if (checkNames) {
	register unsigned i,bit;
	sli->namesPresent=	0;
	for (i=0,bit=1;i<XkbNumIndicators;i++,bit<<=1) {
	    if (sli->names[i]!=None)
		sli->namesPresent|= bit;
	}
    }
    if (checkAccel)
	 XkbCheckIndicatorMaps(dev,sli,XkbAllIndicatorsMask);
    return sli;
}

void
XkbFreeSrvLedInfo(XkbSrvLedInfoPtr sli)
{
    if ((sli->flags&XkbSLI_IsDefault)==0) {
	free(sli->maps);
	free(sli->names);
    }
    sli->maps= NULL;
    sli->names= NULL;
    free(sli);
    return;
}

/*
 * XkbSrvLedInfoPtr
 * XkbCopySrvLedInfo(dev,src,kf,lf)
 *
 * Takes the given XkbSrvLedInfoPtr and duplicates it. A deep copy is made,
 * thus the new copy behaves like the original one and can be freed with
 * XkbFreeSrvLedInfo.
 */
XkbSrvLedInfoPtr
XkbCopySrvLedInfo(	DeviceIntPtr		from,
			XkbSrvLedInfoPtr	src,
			KbdFeedbackPtr		kf,
			LedFeedbackPtr		lf)
{
    XkbSrvLedInfoPtr sli_new = NULL;

    if (!src)
	goto finish;

    sli_new = calloc(1, sizeof( XkbSrvLedInfoRec));
    if (!sli_new)
	goto finish;

    memcpy(sli_new, src, sizeof(XkbSrvLedInfoRec));
    if (sli_new->class == KbdFeedbackClass)
	sli_new->fb.kf = kf;
    else
	sli_new->fb.lf = lf;

    if (!(sli_new->flags & XkbSLI_IsDefault)) {
	sli_new->names= calloc(XkbNumIndicators, sizeof(Atom));
	sli_new->maps= calloc(XkbNumIndicators, sizeof(XkbIndicatorMapRec));
    } /* else sli_new->names/maps is pointing to
	dev->key->xkbInfo->desc->names->indicators;
	dev->key->xkbInfo->desc->names->indicators; */

finish:
    return sli_new;
}

/***====================================================================***/

	/*
	 * XkbSrvLedInfoPtr
	 * XkbFindSrvLedInfo(dev,class,id,needed_parts)
	 *
	 * Finds the XkbSrvLedInfoPtr for the specified 'class' and 'id'
	 * on the device specified by 'dev.'   If the class and id specify
	 * a valid device feedback, this function returns the existing
	 * feedback or allocates a new one.
	 *
	 */

XkbSrvLedInfoPtr
XkbFindSrvLedInfo(	DeviceIntPtr		dev,
			unsigned		class,
			unsigned		id,
			unsigned		needed_parts)
{
XkbSrvLedInfoPtr	sli;

    /* optimization to check for most common case */
    if (((class==XkbDfltXIClass)&&(id==XkbDfltXIId))&&(dev->kbdfeed)) {
	XkbSrvLedInfoPtr	sli;
	sli= dev->kbdfeed->xkb_sli;
	if (dev->kbdfeed->xkb_sli==NULL) {
	    sli= XkbAllocSrvLedInfo(dev,dev->kbdfeed,NULL,needed_parts);
	    dev->kbdfeed->xkb_sli= sli;
	}
	return dev->kbdfeed->xkb_sli;
    }

    sli= NULL;
    if (class==XkbDfltXIClass) {
	if (dev->kbdfeed)	class= KbdFeedbackClass;
	else if (dev->leds)	class= LedFeedbackClass;
	else 			return NULL;
    }
    if (class==KbdFeedbackClass) {
	KbdFeedbackPtr	kf;
	for (kf=dev->kbdfeed;kf!=NULL;kf=kf->next) {
	    if ((id==XkbDfltXIId)||(id==kf->ctrl.id)) {
		if (kf->xkb_sli==NULL)
		    kf->xkb_sli= XkbAllocSrvLedInfo(dev,kf,NULL,needed_parts);
		sli= kf->xkb_sli;
		break;
	    }
	}
    }
    else if (class==LedFeedbackClass) {
	LedFeedbackPtr	lf;
	for (lf=dev->leds;lf!=NULL;lf=lf->next) {
	    if ((id==XkbDfltXIId)||(id==lf->ctrl.id)) {
		if (lf->xkb_sli==NULL)
		    lf->xkb_sli= XkbAllocSrvLedInfo(dev,NULL,lf,needed_parts);
		sli= lf->xkb_sli;
		break;
	    }
	}
    }
    if (sli) {
	if ((sli->names==NULL)&&(needed_parts&XkbXI_IndicatorNamesMask))
	    sli->names= calloc(XkbNumIndicators, sizeof(Atom));
	if ((sli->maps==NULL)&&(needed_parts&XkbXI_IndicatorMapsMask))
	    sli->maps= calloc(XkbNumIndicators, sizeof(XkbIndicatorMapRec));
    }
    return sli;
}

/***====================================================================***/

void
XkbFlushLedEvents(	DeviceIntPtr			dev,
			DeviceIntPtr			kbd,
			XkbSrvLedInfoPtr		sli,
			xkbExtensionDeviceNotify *	ed,
			XkbChangesPtr			changes,
			XkbEventCausePtr		cause)
{
    if (changes) {
	if (changes->indicators.state_changes)
	    XkbDDXUpdateDeviceIndicators(dev,sli,sli->effectiveState);
	XkbSendNotification(kbd,changes,cause);
	memset((char *)changes, 0, sizeof(XkbChangesRec));

	if (XkbAX_NeedFeedback(kbd->key->xkbInfo->desc->ctrls, XkbAX_IndicatorFBMask)) {
		if (sli->effectiveState)
			/* it appears that the which parameter is not used */
			XkbDDXAccessXBeep(dev, _BEEP_LED_ON, XkbAccessXFeedbackMask);
		else
			XkbDDXAccessXBeep(dev, _BEEP_LED_OFF, XkbAccessXFeedbackMask);
	}
    }
    if (ed) {
	if (ed->reason) {
	    if ((dev!=kbd)&&(ed->reason&XkbXI_IndicatorStateMask))
		XkbDDXUpdateDeviceIndicators(dev,sli,sli->effectiveState);
	    XkbSendExtensionDeviceNotify(dev,cause->client,ed);
	}
	memset((char *)ed, 0, sizeof(XkbExtensionDeviceNotify));
    }
    return;
}

/***====================================================================***/

void
XkbApplyLedNameChanges(	DeviceIntPtr 			dev,
			XkbSrvLedInfoPtr		sli,
			unsigned			changed_names,
			xkbExtensionDeviceNotify *	ed,
			XkbChangesPtr			changes,
			XkbEventCausePtr		cause)
{
DeviceIntPtr			kbd;
XkbChangesRec			my_changes;
xkbExtensionDeviceNotify	my_ed;

    if (changed_names==0)
	return;
    if (dev->key && dev->key->xkbInfo)
	 kbd= dev;
    else kbd= inputInfo.keyboard;

    if (ed==NULL) {
	ed= &my_ed;
	memset((char *)ed, 0, sizeof(xkbExtensionDeviceNotify));
    }
    else if ((ed->reason&XkbXI_IndicatorsMask)&&
	     ((ed->ledClass!=sli->class)||(ed->ledID!=sli->id))) {
	XkbFlushLedEvents(dev,kbd,sli,ed,changes,cause);
    }

    if ((kbd==dev)&&(sli->flags&XkbSLI_IsDefault)) {
	if (changes==NULL) {
	   changes= &my_changes;
	   memset((char *)changes, 0, sizeof(XkbChangesRec));
	}
	changes->names.changed|= XkbIndicatorNamesMask;
	changes->names.changed_indicators|= changed_names;
    }

    ed->reason|=	XkbXI_IndicatorNamesMask;
    ed->ledClass= 	sli->class;
    ed->ledID=		sli->id;
    ed->ledsDefined=	sli->namesPresent|sli->mapsPresent;
    ed->ledState=	sli->effectiveState;
    ed->unsupported=	0;
    ed->supported=	XkbXI_AllFeaturesMask;

    if (changes!=&my_changes)	changes= NULL;
    if (ed!=&my_ed)		ed= NULL;
    if (changes || ed)
	XkbFlushLedEvents(dev,kbd,sli,ed,changes,cause);
    return;
}
/***====================================================================***/

	/*
	 * void
	 * XkbApplyLedMapChanges(dev,sli,changed_maps,changes,cause)
	 *
	 * Handles all of the secondary effects of the changes to the
	 * feedback specified by 'sli' on the device specified by 'dev.'
	 *
	 * If 'changed_maps' specifies any indicators, this function generates
	 * XkbExtensionDeviceNotify events and possibly IndicatorMapNotify
	 * events to report the changes, and recalculates the effective
	 * state of each indicator with a changed map.  If any indicators
	 * change state, the server generates XkbExtensionDeviceNotify and
	 * XkbIndicatorStateNotify events as appropriate.
	 *
	 * If 'changes' is non-NULL, this function updates it to reflect
	 * any changes to the keyboard state or controls or to the 'core'
	 * indicator names, maps, or state.   If 'changes' is NULL, this
	 * function generates XKB events as needed to report the changes.
	 * If 'dev' is not a keyboard device, any changes are reported
	 * for the core keyboard.
	 *
	 * The 'cause' specifies the reason for the event (key event or
	 * request) for the change, as reported in some XKB events.
	 */

void
XkbApplyLedMapChanges(	DeviceIntPtr 			dev,
			XkbSrvLedInfoPtr		sli,
			unsigned			changed_maps,
			xkbExtensionDeviceNotify *	ed,
			XkbChangesPtr			changes,
			XkbEventCausePtr		cause)
{
DeviceIntPtr			kbd;
XkbChangesRec			my_changes;
xkbExtensionDeviceNotify	my_ed;

    if (changed_maps==0)
	return;
    if (dev->key && dev->key->xkbInfo)
	 kbd= dev;
    else kbd= inputInfo.keyboard;

    if (ed==NULL) {
	ed= &my_ed;
	memset((char *)ed, 0, sizeof(xkbExtensionDeviceNotify));
    }
    else if ((ed->reason&XkbXI_IndicatorsMask)&&
	     ((ed->ledClass!=sli->class)||(ed->ledID!=sli->id))) {
	XkbFlushLedEvents(dev,kbd,sli,ed,changes,cause);
    }

    if ((kbd==dev)&&(sli->flags&XkbSLI_IsDefault)) {
	if (changes==NULL) {
	    changes= &my_changes;
	    memset((char *)changes, 0, sizeof(XkbChangesRec));
	}
	changes->indicators.map_changes|= changed_maps;
    }

    XkbCheckIndicatorMaps(dev,sli,changed_maps);

    ed->reason|=	XkbXI_IndicatorMapsMask;
    ed->ledClass= 	sli->class;
    ed->ledID=		sli->id;
    ed->ledsDefined=	sli->namesPresent|sli->mapsPresent;
    ed->ledState=	sli->effectiveState;
    ed->unsupported=	0;
    ed->supported=	XkbXI_AllFeaturesMask;

    XkbUpdateLedAutoState(dev,sli,changed_maps,ed,changes,cause);

    if (changes!=&my_changes)	changes= NULL;
    if (ed!=&my_ed)		ed= NULL;
    if (changes || ed)
	XkbFlushLedEvents(dev,kbd,sli,ed,changes,cause);
    return;
}

/***====================================================================***/

void
XkbApplyLedStateChanges(DeviceIntPtr 			dev,
			XkbSrvLedInfoPtr		sli,
			unsigned			changed_leds,
			xkbExtensionDeviceNotify *	ed,
			XkbChangesPtr			changes,
			XkbEventCausePtr		cause)
{
XkbSrvInfoPtr			xkbi;
DeviceIntPtr			kbd;
XkbChangesRec			my_changes;
xkbExtensionDeviceNotify	my_ed;
register unsigned		i,bit,affected;
XkbIndicatorMapPtr		map;
unsigned			oldState;
Bool				kb_changed;

    if (changed_leds==0)
	return;
    if (dev->key && dev->key->xkbInfo)
	 kbd= dev;
    else kbd= inputInfo.keyboard;
    xkbi= kbd->key->xkbInfo;

    if (changes==NULL) {
	changes= &my_changes;
	memset((char *)changes, 0, sizeof(XkbChangesRec));
    }

    kb_changed= FALSE;
    affected= changed_leds;
    oldState= sli->effectiveState;
    for (i=0,bit=1;(i<XkbNumIndicators)&&(affected);i++,bit<<=1) {
	if ((affected&bit)==0)
	    continue;
	affected&= ~bit;
	map= &sli->maps[i];
	if (map->flags&XkbIM_NoExplicit) {
	    sli->explicitState&= ~bit;
	    continue;
	}
	if (map->flags&XkbIM_LEDDrivesKB) {
	    Bool on= ((sli->explicitState&bit)!=0);
	    if (XkbApplyLEDChangeToKeyboard(xkbi,map,on,changes))
		kb_changed= TRUE;
	}
    }
    sli->effectiveState= (sli->autoState|sli->explicitState);
    affected= sli->effectiveState^oldState;

    if (ed==NULL) {
	ed= &my_ed;
	memset((char *)ed, 0, sizeof(xkbExtensionDeviceNotify));
    }
    else if (affected&&(ed->reason&XkbXI_IndicatorsMask)&&
	     ((ed->ledClass!=sli->class)||(ed->ledID!=sli->id))) {
	XkbFlushLedEvents(dev,kbd,sli,ed,changes,cause);
    }

    if ((kbd==dev)&&(sli->flags&XkbSLI_IsDefault))
	changes->indicators.state_changes|= affected;
    if (affected) {
	ed->reason|=		XkbXI_IndicatorStateMask;
	ed->ledClass= 		sli->class;
	ed->ledID=		sli->id;
	ed->ledsDefined=	sli->namesPresent|sli->mapsPresent;
	ed->ledState=		sli->effectiveState;
	ed->unsupported=	0;
	ed->supported=		XkbXI_AllFeaturesMask;
    }

    if (kb_changed) {
	XkbComputeDerivedState(kbd->key->xkbInfo);
	XkbUpdateLedAutoState(dev,sli,sli->mapsPresent,ed,changes,cause);
    }

    if (changes!=&my_changes)	changes= NULL;
    if (ed!=&my_ed)		ed= NULL;
    if (changes || ed)
	XkbFlushLedEvents(dev,kbd,sli,ed,changes,cause);
    if (kb_changed)
	XkbUpdateAllDeviceIndicators(NULL,cause);
    return;
}