xref: /xsrc/external/mit/libX11/dist/src/VisUtil.c

/*

Copyright 1986, 1998  The Open Group

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.

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Except as contained in this notice, the name of The Open Group shall not be
used in advertising or otherwise to promote the sale, use or other dealings
in this Software without prior written authorization from The Open Group.

*/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "Xlibint.h"
#include "Xutil.h"
#include <stdio.h>
#include "reallocarray.h"

/*
 *	This procedure returns a list of visual information structures
 *	that match the specified attributes given in the visual information
 *	template.
 *
 *	If no visuals exist that match the specified attributes, a NULL is
 *	returned.
 *
 *	The choices for visual_info_mask are:
 *
 *		VisualNoMask
 *		VisualIDMask
 *		VisualScreenMask
 *		VisualDepthMask
 *		VisualClassMask
 *		VisualRedMaskMask
 *		VisualGreenMaskMask
 *		VisualBlueMaskMask
 *		VisualColormapSizeMask
 *		VisualBitsPerRGBMask
 *		VisualAllMask
 */

XVisualInfo *XGetVisualInfo(
    Display *dpy,
    register long visual_info_mask,
    register XVisualInfo *visual_info_template,
    int *nitems)	/* RETURN */
{

  register Visual *vp;
  register Depth *dp;
  Screen *sp;
  int ii,screen_s,screen_e,total,count;
  register XVisualInfo *vip,*vip_base;

  /* NOTE: NO HIGH PERFORMING CODE TO BE FOUND HERE */

  LockDisplay(dpy);

  /* ALLOCATE THE ORIGINAL BUFFER; REALLOCED LATER IF OVERFLOW OCCURS;
     FREED AT END IF NO VISUALS ARE FOUND */

  count = 0;
  total = 10;
  if (! (vip_base = vip = Xmallocarray(total, sizeof(XVisualInfo)))) {
      UnlockDisplay(dpy);
      return (XVisualInfo *) NULL;
  }

  /* DETERMINE IF WE DO ALL SCREENS OR ONLY ONE */

  screen_s = 0;
  screen_e = dpy->nscreens;
  if (visual_info_mask & VisualScreenMask)
    {
      screen_s = visual_info_template->screen;
      if (screen_s < 0 || screen_s >= screen_e)
	  screen_e = screen_s;
      else
	  screen_e = screen_s + 1;
    }

  /* LOOP THROUGH SCREENS */

  for (ii=screen_s; ii<screen_e; ii++)
    {
      sp = (Screen *)(&dpy->screens[ii]);

      /* LOOP THROUGH DEPTHS */

      for (dp=sp->depths; dp < (sp->depths + sp->ndepths); dp++)
        {
          if ((visual_info_mask & VisualDepthMask) &&
	      (dp->depth != visual_info_template->depth)) continue;

          /* LOOP THROUGH VISUALS */

	  if (dp->visuals) {
	    for (vp=dp->visuals; vp<(dp->visuals + dp->nvisuals); vp++) {
              if ((visual_info_mask & VisualIDMask) &&
                (vp->visualid != visual_info_template->visualid)) continue;
              if ((visual_info_mask & VisualClassMask) &&
                (vp->class != visual_info_template->class)) continue;
              if ((visual_info_mask & VisualRedMaskMask) &&
                (vp->red_mask != visual_info_template->red_mask)) continue;
              if ((visual_info_mask & VisualGreenMaskMask) &&
                (vp->green_mask != visual_info_template->green_mask)) continue;
              if ((visual_info_mask & VisualBlueMaskMask) &&
                (vp->blue_mask != visual_info_template->blue_mask)) continue;
              if ((visual_info_mask & VisualColormapSizeMask) &&
                (vp->map_entries != visual_info_template->colormap_size)) continue;
              if ((visual_info_mask & VisualBitsPerRGBMask) &&
                (vp->bits_per_rgb != visual_info_template->bits_per_rgb)) continue;

              /* YEA!!! WE FOUND A GOOD ONE */

              if (count+1 > total)
                {
		  XVisualInfo *old_vip_base = vip_base;
                  total += 10;
                  if (! (vip_base = Xreallocarray(vip_base, total,
                                                  sizeof(XVisualInfo)))) {
		      Xfree(old_vip_base);
		      UnlockDisplay(dpy);
		      return (XVisualInfo *) NULL;
		  }
                  vip = &vip_base[count];
                }

              count++;

              vip->visual = _XVIDtoVisual(dpy, vp->visualid);
              vip->visualid = vp->visualid;
              vip->screen = ii;
              vip->depth = dp->depth;
              vip->class = vp->class;
              vip->red_mask = vp->red_mask;
              vip->green_mask = vp->green_mask;
              vip->blue_mask = vp->blue_mask;
              vip->colormap_size = vp->map_entries;
              vip->bits_per_rgb = vp->bits_per_rgb;

              vip++;

            } /* END OF LOOP ON VISUALS */
	  } /* END OF IF THERE ARE ANY VISUALS AT THIS DEPTH */

        } /* END OF LOOP ON DEPTHS */

    } /* END OF LOOP ON SCREENS */

  UnlockDisplay(dpy);

  if (count)
    {
      *nitems = count;
      return vip_base;
    }

  Xfree(vip_base);
  *nitems = 0;
  return NULL;
}


/*
 *	This procedure will return the visual information for a visual
 *      that matches the specified depth and class for a screen.  Since
 *	multiple visuals may exist that match the specified depth and
 *	class, which visual chosen is undefined.
 *
 *	If a visual is found, True is returned as the function value,
 *	otherwise False is returned.
 */

Status XMatchVisualInfo(
	Display *dpy,
	int screen,
	int depth,
	int class,
	XVisualInfo *visual_info) /* RETURNED */
{

  Visual *vp;
  Depth *dp;
  Screen *sp;
  int ii,jj;

  if (screen < 0 || screen >= dpy->nscreens)
      return False;

  LockDisplay(dpy);

  sp = (Screen *)(&dpy->screens[screen]);

  dp = sp->depths;

  for (ii=0; ii < sp->ndepths; ii++)
    {

    /* LOOK THROUGH DEPTHS FOR THE WANTED DEPTH */

    if (dp->depth == depth)
      {
        vp = dp->visuals;

        /* LOOK THROUGH VISUALS FOR THE WANTED CLASS */

	/* if nvisuals == 0 then vp will be NULL */
        for (jj=0; jj<dp->nvisuals; jj++)
          {
            if (vp->class == class)
              {
		visual_info->visual = _XVIDtoVisual(dpy, vp->visualid);
		visual_info->visualid = vp->visualid;
		visual_info->screen = screen;
		visual_info->depth = depth;
		visual_info->class = vp->class;
		visual_info->red_mask = vp->red_mask;
		visual_info->green_mask = vp->green_mask;
		visual_info->blue_mask = vp->blue_mask;
		visual_info->colormap_size = vp->map_entries;
		visual_info->bits_per_rgb = vp->bits_per_rgb;
                UnlockDisplay(dpy);
                return True;
              }
            vp++;
          }
      }

    dp++;

    }

  UnlockDisplay(dpy);

  return False;

}