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path: root/randr/rrproperty.c
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/*
 * Copyright © 2006 Keith Packard
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, 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 the copyright holders not be used in advertising or
 * publicity pertaining to distribution of the software without specific,
 * written prior permission.  The copyright holders make no representations
 * about the suitability of this software for any purpose.  It is provided "as
 * is" without express or implied warranty.
 *
 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL THE COPYRIGHT HOLDERS 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.
 */

#include "randrstr.h"
#include "propertyst.h"
#include "swaprep.h"

static int
DeliverPropertyEvent(WindowPtr pWin, void *value)
{
    xRROutputPropertyNotifyEvent *event = value;
    RREventPtr *pHead, pRREvent;
    ClientPtr client;

    dixLookupResourceByType((pointer *)&pHead, pWin->drawable.id,
			    RREventType, serverClient, DixReadAccess);
    if (!pHead)
	return WT_WALKCHILDREN;

    for (pRREvent = *pHead; pRREvent; pRREvent = pRREvent->next)
    {
	client = pRREvent->client;
	if (client == serverClient || client->clientGone)
	    continue;

	if (!(pRREvent->mask & RROutputPropertyNotifyMask))
	    continue;

	event->sequenceNumber = client->sequence;
	event->window = pRREvent->window->drawable.id;
	if (client->swapped) {
	    int n;
	    swaps(&event->sequenceNumber, n);
	    swapl(&event->window, n);
	}
	WriteEventsToClient(pRREvent->client, 1, (xEvent *)event);
    }

    return WT_WALKCHILDREN;
}

static void RRDeliverPropertyEvent(ScreenPtr pScreen, xEvent *event)
{
    if (!(dispatchException & (DE_RESET | DE_TERMINATE)))
	WalkTree(pScreen, DeliverPropertyEvent, event);
}

void
RRDeleteAllOutputProperties (RROutputPtr output)
{
    RRPropertyPtr prop, next;
    xRROutputPropertyNotifyEvent    event;

    for (prop = output->properties; prop; prop = next)
    {
	next = prop->next;
	event.type = RREventBase + RRNotify;
	event.subCode = RRNotify_OutputProperty;
	event.output = output->id;
	event.state = PropertyDelete;
	event.atom = prop->propertyName;
	event.timestamp = currentTime.milliseconds;
	RRDeliverPropertyEvent (output->pScreen, (xEvent *)&event);
	if (prop->current.data)
	    xfree(prop->current.data);
	if (prop->pending.data)
	    xfree(prop->pending.data);
	xfree(prop);
    }
}

static void
RRInitOutputPropertyValue (RRPropertyValuePtr property_value)
{
    property_value->type = None;
    property_value->format = 0;
    property_value->size = 0;
    property_value->data = NULL;
}

static RRPropertyPtr
RRCreateOutputProperty (Atom property)
{
    RRPropertyPtr   prop;

    prop = (RRPropertyPtr)xalloc(sizeof(RRPropertyRec));
    if (!prop)
	return NULL;
    prop->next = NULL;
    prop->propertyName = property;
    prop->is_pending = FALSE;
    prop->range = FALSE;
    prop->immutable = FALSE;
    prop->num_valid = 0;
    prop->valid_values = NULL;
    RRInitOutputPropertyValue (&prop->current);
    RRInitOutputPropertyValue (&prop->pending);
    return prop;
}

static void
RRDestroyOutputProperty (RRPropertyPtr prop)
{
    if (prop->valid_values)
	xfree (prop->valid_values);
    if (prop->current.data)
	xfree(prop->current.data);
    if (prop->pending.data)
	xfree(prop->pending.data);
    if (prop->valid_values)
	xfree(prop->valid_values);
    xfree(prop);
}

void
RRDeleteOutputProperty (RROutputPtr output, Atom property)
{
    RRPropertyPtr	prop, *prev;
    xRROutputPropertyNotifyEvent    event;

    for (prev = &output->properties; (prop = *prev); prev = &(prop->next))
	if (prop->propertyName == property)
	    break;
    if (prop)
    {
	*prev = prop->next;
	event.type = RREventBase + RRNotify;
	event.subCode = RRNotify_OutputProperty;
	event.output = output->id;
	event.state = PropertyDelete;
	event.atom = prop->propertyName;
	event.timestamp = currentTime.milliseconds;
	RRDeliverPropertyEvent (output->pScreen, (xEvent *)&event);
	RRDestroyOutputProperty (prop);
    }
}

int
RRChangeOutputProperty (RROutputPtr output, Atom property, Atom type,
			int format, int mode, unsigned long len,
			pointer value, Bool sendevent, Bool pending)
{
    RRPropertyPtr		    prop;
    xRROutputPropertyNotifyEvent    event;
    rrScrPrivPtr		    pScrPriv = rrGetScrPriv(output->pScreen);
    int				    size_in_bytes;
    int				    total_size;
    unsigned long		    total_len;
    RRPropertyValuePtr		    prop_value;
    RRPropertyValueRec		    new_value;
    Bool			    add = FALSE;

    size_in_bytes = format >> 3;

    /* first see if property already exists */
    prop = RRQueryOutputProperty (output, property);
    if (!prop)   /* just add to list */
    {
	prop = RRCreateOutputProperty (property);
	if (!prop)
	    return(BadAlloc);
	add = TRUE;
	mode = PropModeReplace;
    }
    if (pending && prop->is_pending)
	prop_value = &prop->pending;
    else
	prop_value = &prop->current;

    /* To append or prepend to a property the request format and type
     must match those of the already defined property.  The
     existing format and type are irrelevant when using the mode
     "PropModeReplace" since they will be written over. */

    if ((format != prop_value->format) && (mode != PropModeReplace))
	return(BadMatch);
    if ((prop_value->type != type) && (mode != PropModeReplace))
	return(BadMatch);
    new_value = *prop_value;
    if (mode == PropModeReplace)
	total_len = len;
    else
	total_len = prop_value->size + len;

    if (mode == PropModeReplace || len > 0)
    {
	pointer	    new_data = NULL, old_data = NULL;

	total_size = total_len * size_in_bytes;
	new_value.data = (pointer)xalloc (total_size);
	if (!new_value.data && total_size)
	{
	    if (add)
		RRDestroyOutputProperty (prop);
	    return BadAlloc;
	}
	new_value.size = len;
	new_value.type = type;
	new_value.format = format;

	switch (mode) {
	case PropModeReplace:
	    new_data = new_value.data;
	    old_data = NULL;
	    break;
	case PropModeAppend:
	    new_data = (pointer) (((char *) new_value.data) + 
				  (prop_value->size * size_in_bytes));
	    old_data = new_value.data;
	    break;
	case PropModePrepend:
	    new_data = new_value.data;
	    old_data = (pointer) (((char *) new_value.data) + 
				  (prop_value->size * size_in_bytes));
	    break;
	}
	if (new_data)
	    memcpy ((char *) new_data, (char *) value, len * size_in_bytes);
	if (old_data)
	    memcpy ((char *) old_data, (char *) prop_value->data, 
		    prop_value->size * size_in_bytes);

	if (pending && pScrPriv->rrOutputSetProperty &&
	    !pScrPriv->rrOutputSetProperty(output->pScreen, output,
					   prop->propertyName, &new_value))
	{
	    if (new_value.data)
		xfree (new_value.data);
	    return (BadValue);
	}
	if (prop_value->data)
	    xfree (prop_value->data);
	*prop_value = new_value;
    }

    else if (len == 0)
    {
	/* do nothing */
    }

    if (add)
    {
	prop->next = output->properties;
	output->properties = prop;
    }

    if (pending && prop->is_pending)
	output->pendingProperties = TRUE;

    if (sendevent)
    {
	event.type = RREventBase + RRNotify;
	event.subCode = RRNotify_OutputProperty;
	event.output = output->id;
	event.state = PropertyNewValue;
	event.atom = prop->propertyName;
	event.timestamp = currentTime.milliseconds;
	RRDeliverPropertyEvent (output->pScreen, (xEvent *)&event);
    }
    return(Success);
}

Bool
RRPostPendingProperties (RROutputPtr output)
{
    RRPropertyValuePtr	pending_value;
    RRPropertyValuePtr	current_value;
    RRPropertyPtr	property;
    Bool		ret = TRUE;

    if (!output->pendingProperties)
	return TRUE;
    
    output->pendingProperties = FALSE;
    for (property = output->properties; property; property = property->next)
    {
	/* Skip non-pending properties */
	if (!property->is_pending)
	    continue;
	
	pending_value = &property->pending;
	current_value = &property->current;

	/*
	 * If the pending and current values are equal, don't mark it
	 * as changed (which would deliver an event)
	 */
	if (pending_value->type == current_value->type &&
	    pending_value->format == current_value->format &&
	    pending_value->size == current_value->size &&
	    !memcmp (pending_value->data, current_value->data,
		     pending_value->size))
	    continue;

	if (RRChangeOutputProperty (output, property->propertyName,
				    pending_value->type, pending_value->format,
				    PropModeReplace, pending_value->size,
				    pending_value->data, TRUE,
				    FALSE) != Success)
	    ret = FALSE;
    }
    return ret;
}

RRPropertyPtr
RRQueryOutputProperty (RROutputPtr output, Atom property)
{
    RRPropertyPtr   prop;
    
    for (prop = output->properties; prop; prop = prop->next)
	if (prop->propertyName == property)
	    return prop;
    return NULL;
}
		       
RRPropertyValuePtr
RRGetOutputProperty (RROutputPtr output, Atom property, Bool pending)
{
    RRPropertyPtr   prop = RRQueryOutputProperty (output, property);
    rrScrPrivPtr    pScrPriv = rrGetScrPriv(output->pScreen);

    if (!prop)
	return NULL;
    if (pending && prop->is_pending)
	return &prop->pending;
    else {
#if RANDR_13_INTERFACE
	/* If we can, try to update the property value first */
	if (pScrPriv->rrOutputGetProperty)
	    pScrPriv->rrOutputGetProperty(output->pScreen, output,
					  prop->propertyName);
#endif
	return &prop->current;
    }
}

int
RRConfigureOutputProperty (RROutputPtr output, Atom property,
			   Bool pending, Bool range, Bool immutable,
			   int num_values, INT32 *values)
{
    RRPropertyPtr   prop = RRQueryOutputProperty (output, property);
    Bool	    add = FALSE;
    INT32	    *new_values;

    if (!prop)
    {
        prop = RRCreateOutputProperty (property);
	if (!prop)
	    return(BadAlloc);
	add = TRUE;
    } else if (prop->immutable && !immutable)
	return(BadAccess);
    
    /*
     * ranges must have even number of values
     */
    if (range && (num_values & 1))
	return BadMatch;

    new_values = xalloc (num_values * sizeof (INT32));
    if (!new_values && num_values)
	return BadAlloc;
    if (num_values)
	memcpy (new_values, values, num_values * sizeof (INT32));
    
    /*
     * Property moving from pending to non-pending
     * loses any pending values
     */
    if (prop->is_pending && !pending)
    {
	if (prop->pending.data)
	    xfree (prop->pending.data);
	RRInitOutputPropertyValue (&prop->pending);
    }

    prop->is_pending = pending;
    prop->range = range;
    prop->immutable = immutable;
    prop->num_valid = num_values;
    if (prop->valid_values)
	xfree (prop->valid_values);
    prop->valid_values = new_values;

    if (add) {
	prop->next = output->properties;
	output->properties = prop;
    }

    return Success;
}

int
ProcRRListOutputProperties (ClientPtr client)
{
    REQUEST(xRRListOutputPropertiesReq);
    Atom			    *pAtoms = NULL, *temppAtoms;
    xRRListOutputPropertiesReply    rep;
    int				    numProps = 0;
    RROutputPtr			    output;
    RRPropertyPtr			    prop;
    
    REQUEST_SIZE_MATCH(xRRListOutputPropertiesReq);

    VERIFY_RR_OUTPUT(stuff->output, output, DixReadAccess);

    for (prop = output->properties; prop; prop = prop->next)
	numProps++;
    if (numProps)
        if(!(pAtoms = (Atom *)xalloc(numProps * sizeof(Atom))))
            return(BadAlloc);

    rep.type = X_Reply;
    rep.length = bytes_to_int32(numProps * sizeof(Atom));
    rep.sequenceNumber = client->sequence;
    rep.nAtoms = numProps;
    if (client->swapped) 
    {
	int n;
	swaps (&rep.sequenceNumber, n);
	swapl (&rep.length, n);
	swaps (&rep.nAtoms, n);
    }
    temppAtoms = pAtoms;
    for (prop = output->properties; prop; prop = prop->next)
	*temppAtoms++ = prop->propertyName;

    WriteToClient(client, sizeof(xRRListOutputPropertiesReply), (char*)&rep);
    if (numProps)
    {
        client->pSwapReplyFunc = (ReplySwapPtr)Swap32Write;
        WriteSwappedDataToClient(client, numProps * sizeof(Atom), pAtoms);
        xfree(pAtoms);
    }
    return(client->noClientException);
}

int
ProcRRQueryOutputProperty (ClientPtr client)
{
    REQUEST(xRRQueryOutputPropertyReq);
    xRRQueryOutputPropertyReply	    rep;
    RROutputPtr			    output;
    RRPropertyPtr		    prop;
    char *extra = NULL;
    
    REQUEST_SIZE_MATCH(xRRQueryOutputPropertyReq);

    VERIFY_RR_OUTPUT(stuff->output, output, DixReadAccess);
    
    prop = RRQueryOutputProperty (output, stuff->property);
    if (!prop)
	return BadName;
    
    if (prop->num_valid) {
	extra = xalloc(prop->num_valid * sizeof(INT32));
	if (!extra)
	    return BadAlloc;
    }
    rep.type = X_Reply;
    rep.length = prop->num_valid;
    rep.sequenceNumber = client->sequence;
    rep.pending = prop->is_pending;
    rep.range = prop->range;
    rep.immutable = prop->immutable;
    if (client->swapped) 
    {
	int n;
	swaps (&rep.sequenceNumber, n);
	swapl (&rep.length, n);
    }
    WriteToClient (client, sizeof (xRRQueryOutputPropertyReply), (char*)&rep);
    if (prop->num_valid)
    {
        memcpy(extra, prop->valid_values, prop->num_valid * sizeof(INT32));
        client->pSwapReplyFunc = (ReplySwapPtr)Swap32Write;
        WriteSwappedDataToClient(client, prop->num_valid * sizeof(INT32),
				 extra);
        xfree(extra);
    }
    return(client->noClientException);
}

int
ProcRRConfigureOutputProperty (ClientPtr client)
{
    REQUEST(xRRConfigureOutputPropertyReq);
    RROutputPtr				output;
    int					num_valid;
    
    REQUEST_AT_LEAST_SIZE(xRRConfigureOutputPropertyReq);

    VERIFY_RR_OUTPUT(stuff->output, output, DixReadAccess);
    
    num_valid = stuff->length - bytes_to_int32(sizeof (xRRConfigureOutputPropertyReq));
    return RRConfigureOutputProperty (output, stuff->property,
				      stuff->pending, stuff->range,
				      FALSE, num_valid, 
				      (INT32 *) (stuff + 1));
}

int
ProcRRChangeOutputProperty (ClientPtr client)
{
    REQUEST(xRRChangeOutputPropertyReq);
    RROutputPtr	    output;
    char	    format, mode;
    unsigned long   len;
    int		    sizeInBytes;
    int		    totalSize;
    int		    err;

    REQUEST_AT_LEAST_SIZE(xRRChangeOutputPropertyReq);
    UpdateCurrentTime();
    format = stuff->format;
    mode = stuff->mode;
    if ((mode != PropModeReplace) && (mode != PropModeAppend) &&
	(mode != PropModePrepend))
    {
	client->errorValue = mode;
	return BadValue;
    }
    if ((format != 8) && (format != 16) && (format != 32))
    {
	client->errorValue = format;
        return BadValue;
    }
    len = stuff->nUnits;
    if (len > bytes_to_int32((0xffffffff - sizeof(xChangePropertyReq))))
	return BadLength;
    sizeInBytes = format>>3;
    totalSize = len * sizeInBytes;
    REQUEST_FIXED_SIZE(xRRChangeOutputPropertyReq, totalSize);

    VERIFY_RR_OUTPUT(stuff->output, output, DixReadAccess);
    
    if (!ValidAtom(stuff->property))
    {
	client->errorValue = stuff->property;
	return(BadAtom);
    }
    if (!ValidAtom(stuff->type))
    {
	client->errorValue = stuff->type;
	return(BadAtom);
    }

    err = RRChangeOutputProperty(output, stuff->property,
				 stuff->type, (int)format,
				 (int)mode, len, (pointer)&stuff[1], TRUE, TRUE);
    if (err != Success)
	return err;
    else
	return client->noClientException;
}

int
ProcRRDeleteOutputProperty (ClientPtr client)
{
    REQUEST(xRRDeleteOutputPropertyReq);
    RROutputPtr	output;
              
    REQUEST_SIZE_MATCH(xRRDeleteOutputPropertyReq);
    UpdateCurrentTime();
    VERIFY_RR_OUTPUT(stuff->output, output, DixReadAccess);
    
    if (!ValidAtom(stuff->property))
    {
	client->errorValue = stuff->property;
	return (BadAtom);
    }


    RRDeleteOutputProperty(output, stuff->property);
    return client->noClientException;
}

int
ProcRRGetOutputProperty (ClientPtr client)
{
    REQUEST(xRRGetOutputPropertyReq);
    RRPropertyPtr		prop, *prev;
    RRPropertyValuePtr		prop_value;
    unsigned long		n, len, ind;
    RROutputPtr			output;
    xRRGetOutputPropertyReply	reply;
    char			*extra = NULL;

    REQUEST_SIZE_MATCH(xRRGetOutputPropertyReq);
    if (stuff->delete)
	UpdateCurrentTime();
    VERIFY_RR_OUTPUT(stuff->output, output,
		     stuff->delete ? DixWriteAccess : DixReadAccess);

    if (!ValidAtom(stuff->property))
    {
	client->errorValue = stuff->property;
	return(BadAtom);
    }
    if ((stuff->delete != xTrue) && (stuff->delete != xFalse))
    {
	client->errorValue = stuff->delete;
	return(BadValue);
    }
    if ((stuff->type != AnyPropertyType) && !ValidAtom(stuff->type))
    {
	client->errorValue = stuff->type;
	return(BadAtom);
    }

    for (prev = &output->properties; (prop = *prev); prev = &prop->next)
	if (prop->propertyName == stuff->property) 
	    break;

    reply.type = X_Reply;
    reply.sequenceNumber = client->sequence;
    if (!prop) 
    {
	reply.nItems = 0;
	reply.length = 0;
	reply.bytesAfter = 0;
	reply.propertyType = None;
	reply.format = 0;
	if (client->swapped) {
	    int n;

	    swaps(&reply.sequenceNumber, n);
	    swapl(&reply.length, n);
	    swapl(&reply.propertyType, n);
	    swapl(&reply.bytesAfter, n);
	    swapl(&reply.nItems, n);
	}
	WriteToClient(client, sizeof(xRRGetOutputPropertyReply), &reply);
	return(client->noClientException);
    }

    if (prop->immutable && stuff->delete)
	return BadAccess;

    prop_value = RRGetOutputProperty(output, stuff->property, stuff->pending);
    if (!prop_value)
	return BadAtom;

    /* If the request type and actual type don't match. Return the
    property information, but not the data. */

    if (((stuff->type != prop_value->type) &&
	 (stuff->type != AnyPropertyType))
       )
    {
	reply.bytesAfter = prop_value->size;
	reply.format = prop_value->format;
	reply.length = 0;
	reply.nItems = 0;
	reply.propertyType = prop_value->type;
	if (client->swapped) {
	    int n;

	    swaps(&reply.sequenceNumber, n);
	    swapl(&reply.length, n);
	    swapl(&reply.propertyType, n);
	    swapl(&reply.bytesAfter, n);
	    swapl(&reply.nItems, n);
	}
	WriteToClient(client, sizeof(xRRGetOutputPropertyReply), &reply);
	return(client->noClientException);
    }

/*
 *  Return type, format, value to client
 */
    n = (prop_value->format/8) * prop_value->size; /* size (bytes) of prop */
    ind = stuff->longOffset << 2;        

   /* If longOffset is invalid such that it causes "len" to
	    be negative, it's a value error. */

    if (n < ind)
    {
	client->errorValue = stuff->longOffset;
	return BadValue;
    }

    len = min(n - ind, 4 * stuff->longLength);

    if (len) {
	extra = xalloc(len);
	if (!extra)
	    return BadAlloc;
    }
    reply.bytesAfter = n - (ind + len);
    reply.format = prop_value->format;
    reply.length = bytes_to_int32(len);
    if (prop_value->format)
	reply.nItems = len / (prop_value->format / 8);
    else
	reply.nItems = 0;
    reply.propertyType = prop_value->type;

    if (stuff->delete && (reply.bytesAfter == 0))
    {
	xRROutputPropertyNotifyEvent    event;

	event.type = RREventBase + RRNotify;
	event.subCode = RRNotify_OutputProperty;
	event.output = output->id;
	event.state = PropertyDelete;
	event.atom = prop->propertyName;
	event.timestamp = currentTime.milliseconds;
	RRDeliverPropertyEvent (output->pScreen, (xEvent *)&event);
    }

    if (client->swapped) {
	int n;

	swaps(&reply.sequenceNumber, n);
	swapl(&reply.length, n);
	swapl(&reply.propertyType, n);
	swapl(&reply.bytesAfter, n);
	swapl(&reply.nItems, n);
    }
    WriteToClient(client, sizeof(xGenericReply), &reply);
    if (len)
    {
	memcpy(extra, (char *)prop_value->data + ind, len);
	switch (reply.format) {
	case 32: client->pSwapReplyFunc = (ReplySwapPtr)CopySwap32Write; break;
	case 16: client->pSwapReplyFunc = (ReplySwapPtr)CopySwap16Write; break;
	default: client->pSwapReplyFunc = (ReplySwapPtr)WriteToClient; break;
	}
	WriteSwappedDataToClient(client, len,
				 extra);
	xfree(extra);
    }

    if (stuff->delete && (reply.bytesAfter == 0))
    { /* delete the Property */
	*prev = prop->next;
	RRDestroyOutputProperty (prop);
    }
    return(client->noClientException);
}