Bool XRenderQueryExtension (Display *dpy, int *event_basep, int *error_basep)
{
XRenderExtDisplayInfo *info = XRenderFindDisplay (dpy);
if (RenderHasExtension(info)) {
*event_basep = info->codes->first_event;
*error_basep = info->codes->first_error;
return True;
} else {
return False;
}
}
Status XRenderQueryVersion (Display *dpy,
int *major_versionp,
int *minor_versionp)
{
XRenderExtDisplayInfo *info = XRenderFindDisplay (dpy);
XRenderInfo *xri;
if (!RenderHasExtension (info))
return 0;
if (!XRenderQueryFormats (dpy))
return 0;
xri = info->info;
*major_versionp = xri->major_version;
*minor_versionp = xri->minor_version;
return 1;
}
XFilters *
XRenderQueryFilters (Display *dpy, Drawable drawable)
{
XRenderExtDisplayInfo *info = XRenderFindDisplay (dpy);
XRenderInfo *xri;
xRenderQueryFiltersReq *req;
xRenderQueryFiltersReply rep;
XFilters *filters;
char *name;
char len;
int i;
long nbytes, nbytesAlias, nbytesName;
if (!RenderHasExtension (info))
return NULL;
if (!XRenderQueryFormats (dpy))
return NULL;
xri = info->info;
if (xri->minor_version < 6)
return NULL;
LockDisplay (dpy);
GetReq (RenderQueryFilters, req);
req->reqType = info->codes->major_opcode;
req->renderReqType = X_RenderQueryFilters;
req->drawable = drawable;
if (!_XReply (dpy, (xReply *) &rep, 0, xFalse))
{
UnlockDisplay (dpy);
SyncHandle ();
return NULL;
}
/*
* Compute total number of bytes for filter names
*/
nbytes = (long)rep.length << 2;
nbytesAlias = rep.numAliases * 2;
if (rep.numAliases & 1)
nbytesAlias += 2;
nbytesName = nbytes - nbytesAlias;
/*
* Allocate one giant block for the whole data structure
*/
filters = Xmalloc (sizeof (XFilters) +
rep.numFilters * sizeof (char *) +
rep.numAliases * sizeof (short) +
nbytesName);
if (!filters)
{
_XEatData (dpy, (unsigned long) rep.length << 2);
UnlockDisplay (dpy);
SyncHandle ();
return NULL;
}
/*
* Layout:
* XFilters
* numFilters char * pointers to filter names
* numAliases short alias values
* nbytesName char strings
*/
filters->nfilter = rep.numFilters;
filters->nalias = rep.numAliases;
filters->filter = (char **) (filters + 1);
filters->alias = (short *) (filters->filter + rep.numFilters);
name = (char *) (filters->alias + rep.numAliases);
/*
* Read the filter aliases
*/
_XRead16Pad (dpy, filters->alias, 2 * rep.numAliases);
/*
* Read the filter names
*/
for (i = 0; i < rep.numFilters; i++)
{
int l;
_XRead (dpy, &len, 1);
l = len & 0xff;
filters->filter[i] = name;
_XRead (dpy, name, l);
name[l] = '\0';
name += l + 1;
}
i = name - (char *) (filters->alias + rep.numAliases);
if (i & 3)
_XEatData (dpy, 4 - (i & 3));
UnlockDisplay (dpy);
SyncHandle ();
return filters;
}
