From edb5253dfa0751e451dca7c9a494be4609390545 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Kristian=20H=C3=B8gsberg?= Date: Thu, 8 Apr 2010 22:09:11 -0400 Subject: [PATCH] glx: Fix config chooser logic for 'mask' matching When matching attributes using the 'mask' matching criteria, the spec says that "Only GLXFBConfigs for which the set bits of attribute include all the bits that are set in the requested value are considered. (Additional bits might be set in the attribute)." The current test returns true if the two bit masks have bits in common, specifically it matches even if the requested value has bits set that are not set in the fbconfig attribute. For example, an application asking for GLX_DRAWABLE_TYPE, GLX_PIXMAP_BIT | GLX_PBUFFER_BIT, as glxpbdemo does, will match fbconfigs that don't support pbuffer rendering, as long as they support pixmap rendering. Reviewed-by: Ian Romanick --- src/glx/glxcmds.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/src/glx/glxcmds.c b/src/glx/glxcmds.c index 7cdd42caf02..e256a078f19 100644 --- a/src/glx/glxcmds.c +++ b/src/glx/glxcmds.c @@ -1110,6 +1110,13 @@ init_fbconfig_for_chooser(__GLcontextModes * config, } \ } while ( 0 ) +/* Test that all bits from a are contained in b */ +#define MATCH_MASK(param) \ + do { \ + if ((a->param & ~b->param) != 0) \ + return False; \ + } while (0); + /** * Determine if two GLXFBConfigs are compatible. * @@ -1148,11 +1155,8 @@ fbconfigs_compatible(const __GLcontextModes * const a, MATCH_DONT_CARE(stereoMode); MATCH_EXACT(level); - if (((a->drawableType & b->drawableType) == 0) - || ((a->renderType & b->renderType) == 0)) { - return False; - } - + MATCH_MASK(drawableType); + MATCH_MASK(renderType); /* There is a bug in a few of the XFree86 DDX drivers. They contain * visuals with a "transparent type" of 0 when they really mean GLX_NONE. -- 2.30.2