Mercurial > sdl-ios-xcode
view src/video/Xext/extensions/extutil.h @ 1544:ab1e4c41ab71
Fixed bug #33
Mike Frysinger wrote:
> with libsdl-1.2.9, some games (like bomberclone) started
> segfaulting in Gentoo
[...snip...]
> the last change in the last hunk:
[...snip...]
> if i change the statement to read:
> (table[which].blit_features & GetBlitFeatures()) == GetBlitFeatures()
> bomberclone no longer segfaults on my box
Alex Volkov wrote:
> The test "(table[which].blit_features & GetBlitFeatures()) ==
> table[which].blit_features)" is correct, and the previous
> "(table[which].cpu_mmx == SDL_HasMMX())" was actually broken.
I think there is potentially a slightly different cause of the above problem.
During the introduction of the Altivec code, the blit_table struct field
'alpha' got changed from a straightforward enum to a bitmask, which makes
perfect sense by itself. However, now the table driven blitter selection code
in SDL_CalculateBlitN() can choose the wrong blitters when searching for a
NO_ALPHA blitter because of the following code:
int a_need = 0;
...
(a_need & table[which].alpha) == a_need &&
When searching through the normal_blit_2[] table, a SET_ALPHA blitter (like
Blit_RGB565_ARGB8888) can now be selected instead of a NO_ALPHA one, causing
alpha channel bits to appear in a non-alpha destination surface. I suppose this
could theoretically be an indirect cause of the segfault mentioned above.
I *think* this can be fixed by changing to
int a_need = NO_ALPHA;
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Wed, 15 Mar 2006 15:47:49 +0000 |
parents | c0a74f199ecf |
children | 3ba88cb7eb1b |
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/* * $Xorg: extutil.h,v 1.4 2001/02/09 02:03:24 xorgcvs Exp $ * Copyright 1989, 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. * * Author: Jim Fulton, MIT The Open Group * * Xlib Extension-Writing Utilities * * This package contains utilities for writing the client API for various * protocol extensions. THESE INTERFACES ARE NOT PART OF THE X STANDARD AND * ARE SUBJECT TO CHANGE! */ /* $XFree86: xc/include/extensions/extutil.h,v 1.9 2001/12/14 19:53:28 dawes Exp $ */ #ifndef _EXTUTIL_H_ #define _EXTUTIL_H_ #include "SDL_stdinc.h" /* For portable string functions */ #include <X11/extensions/Xext.h> /* * We need to keep a list of open displays since the Xlib display list isn't * public. We also have to per-display info in a separate block since it isn't * stored directly in the Display structure. */ typedef struct _XExtDisplayInfo { struct _XExtDisplayInfo *next; /* keep a linked list */ Display *display; /* which display this is */ XExtCodes *codes; /* the extension protocol codes */ XPointer data; /* extra data for extension to use */ } XExtDisplayInfo; typedef struct _XExtensionInfo { XExtDisplayInfo *head; /* start of list */ XExtDisplayInfo *cur; /* most recently used */ int ndisplays; /* number of displays */ } XExtensionInfo; typedef struct _XExtensionHooks { int (*create_gc)( #if NeedNestedPrototypes Display* /* display */, GC /* gc */, XExtCodes* /* codes */ #endif ); int (*copy_gc)( #if NeedNestedPrototypes Display* /* display */, GC /* gc */, XExtCodes* /* codes */ #endif ); int (*flush_gc)( #if NeedNestedPrototypes Display* /* display */, GC /* gc */, XExtCodes* /* codes */ #endif ); int (*free_gc)( #if NeedNestedPrototypes Display* /* display */, GC /* gc */, XExtCodes* /* codes */ #endif ); int (*create_font)( #if NeedNestedPrototypes Display* /* display */, XFontStruct* /* fs */, XExtCodes* /* codes */ #endif ); int (*free_font)( #if NeedNestedPrototypes Display* /* display */, XFontStruct* /* fs */, XExtCodes* /* codes */ #endif ); int (*close_display)( #if NeedNestedPrototypes Display* /* display */, XExtCodes* /* codes */ #endif ); Bool (*wire_to_event)( #if NeedNestedPrototypes Display* /* display */, XEvent* /* re */, xEvent* /* event */ #endif ); Status (*event_to_wire)( #if NeedNestedPrototypes Display* /* display */, XEvent* /* re */, xEvent* /* event */ #endif ); int (*error)( #if NeedNestedPrototypes Display* /* display */, xError* /* err */, XExtCodes* /* codes */, int* /* ret_code */ #endif ); char *(*error_string)( #if NeedNestedPrototypes Display* /* display */, int /* code */, XExtCodes* /* codes */, char* /* buffer */, int /* nbytes */ #endif ); } XExtensionHooks; extern XExtensionInfo *XextCreateExtension( #if NeedFunctionPrototypes void #endif ); extern void XextDestroyExtension( #if NeedFunctionPrototypes XExtensionInfo* /* info */ #endif ); extern XExtDisplayInfo *XextAddDisplay( #if NeedFunctionPrototypes XExtensionInfo* /* extinfo */, Display* /* dpy */, char* /* ext_name */, XExtensionHooks* /* hooks */, int /* nevents */, XPointer /* data */ #endif ); extern int XextRemoveDisplay( #if NeedFunctionPrototypes XExtensionInfo* /* extinfo */, Display* /* dpy */ #endif ); extern XExtDisplayInfo *XextFindDisplay( #if NeedFunctionPrototypes XExtensionInfo* /* extinfo */, Display* /* dpy */ #endif ); #define XextHasExtension(i) ((i) && ((i)->codes)) #define XextCheckExtension(dpy,i,name,val) \ if (!XextHasExtension(i)) { pXMissingExtension (dpy, name); return val; } #define XextSimpleCheckExtension(dpy,i,name) \ if (!XextHasExtension(i)) { pXMissingExtension (dpy, name); return; } /* * helper macros to generate code that is common to all extensions; caller * should prefix it with static if extension source is in one file; this * could be a utility function, but have to stack 6 unused arguments for * something that is called many, many times would be bad. */ #define XEXT_GENERATE_FIND_DISPLAY(proc,extinfo,extname,hooks,nev,data) \ XExtDisplayInfo *proc (Display *dpy) \ { \ XExtDisplayInfo *dpyinfo; \ if (!extinfo) { if (!(extinfo = pXextCreateExtension())) return NULL; } \ if (!(dpyinfo = pXextFindDisplay (extinfo, dpy))) \ dpyinfo = pXextAddDisplay (extinfo,dpy,extname,hooks,nev,data); \ return dpyinfo; \ } #define XEXT_FIND_DISPLAY_PROTO(proc) \ XExtDisplayInfo *proc(Display *dpy) #define XEXT_GENERATE_CLOSE_DISPLAY(proc,extinfo) \ int proc (Display *dpy, XExtCodes *codes) \ { \ return pXextRemoveDisplay (extinfo, dpy); \ } #define XEXT_CLOSE_DISPLAY_PROTO(proc) \ int proc(Display *dpy, XExtCodes *codes) #define XEXT_GENERATE_ERROR_STRING(proc,extname,nerr,errl) \ char *proc (Display *dpy, int code, XExtCodes *codes, char *buf, int n) \ { \ code -= codes->first_error; \ if (code >= 0 && code < nerr) { \ char tmp[256]; \ SDL_snprintf (tmp, SDL_arraysize(tmp), "%s.%d", extname, code); \ pXGetErrorDatabaseText (dpy, "XProtoError", tmp, errl[code], buf, n); \ return buf; \ } \ return (char *)0; \ } #define XEXT_ERROR_STRING_PROTO(proc) \ char *proc(Display *dpy, int code, XExtCodes *codes, char *buf, int n) #endif