Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!elroy.jpl.nasa.gov!ncar!boulder!stan!garya!garya
From: garya@garya.Solbourne.COM (Gary Aitken)
Newsgroups: comp.windows.x
Subject: XAllocColor bug
Message-ID: <1990Nov30.204721.21570@Solbourne.COM>
Date: 30 Nov 90 20:47:21 GMT
Sender: news@Solbourne.COM
Organization: Solbourne Computer, Inc.
Lines: 55

The following program demonstrates a bug when trying to
allocate a color cell.
This is in the X11R4 server.
===================== cut here ======================
/*
 *	If:
 *		A color cell is allocated using XAllocColorCells
 *		The allocated color cell is configured using XStoreColor
 *	Then:
 *		An attempt to use the same color cell via XAllocColor will fail in one of two ways:
 *			If additional color cell is available:	(The case in the program below)
 *				A new one will be allocated.
 *			Else:
 *				XAllocColor will fail (return 0)
 *		Both of these are bugs; in both cases, the previously allocated cell should be returned
 */
#include <X11/X.h>
#include <X11/Xlib.h>

 main (argc, argv)
			int		argc ;
			char		**argv ;
{
			Display		*dpy ;
			int		screen;
			Window		win ;
			XColor		clr_def ;
			Colormap	color_map ;
			Colormap	def_color_map ;
			unsigned long	pxl ;


	dpy = XOpenDisplay(0);
	screen = DefaultScreen(dpy);
	def_color_map = DefaultColormapOfScreen(ScreenOfDisplay(dpy,screen)) ;
	XSynchronize(dpy,1) ;
	win = XDefaultRootWindow(dpy) ;
	if (color_map = XCreateColormap(dpy, win, DefaultVisual(dpy,screen), AllocNone)) {
		XAllocColorCells(dpy, color_map, True, 0, 0, &pxl, 1);
		printf("pixel allocated: %d\n",pxl) ;
		clr_def.pixel = pxl ;
		clr_def.red = 0 ;
		clr_def.green = 0 ;
		clr_def.blue = 0 ;
		clr_def.flags = DoRed|DoGreen|DoBlue ;
		XStoreColor(dpy, color_map, clr_def);
		if (XAllocColor(dpy,color_map,&clr_def))
			printf("pixel: %d\n",clr_def.pixel) ;
	}
}
--
Gary Aitken

Solbourne Computer Inc.    ARPA: garya@Solbourne.COM
Longmont, CO               UUCP: !{boulder,sun}!stan!garya