Mercurial > sdl-ios-xcode
view src/video/xbios/SDL_xbios.h @ 1176:dd2a8deeb26d
Date: Mon, 17 Oct 2005 20:09:03 -0400
From: Mark Schreiber <mark7@alumni.cmu.edu>
To: ryan@clutteredmind.org
Subject: [PATCH]SDL mprotect() crash fix
(I'm going to throw this patch your way at the suggestion of #SDL --
for some reason, I had some difficulty sending it to the main list
last time, and I go bonkers subscribing to send each email or
patch...)
Currently, when I run SDL applications as non-root using
SDL_VIDEODRIVER=dga, the fbdev fallback mprotect()s read/write the
proper size of mmapped /dev/fb0 (7.5MB), but on framebuffer release
mprotect()s read-only the range by the entire size of my video memory
(128MB), which causes a segfault:
#0 0x002a9a27 in ?? () from /lib/libc.so.6
#1 0x04a63eb6 in SDL_XDGAUnmapFramebuffer (screen=3D0) at XF86DGA2.c:978
#2 0x04a63efc in SDL_XDGACloseFramebuffer (dpy=3D0x9d3f008, screen=3D0)
at XF86DGA2.c:268
#3 0x04a68b57 in DGA_Available () at SDL_dgavideo.c:98
#4 0x04a53677 in SDL_VideoInit (driver_name=3D0xbfb0bfc7 "dga", flags=3D0)
at SDL_video.c:180
#5 0x04a2613f in SDL_InitSubSystem (flags=3D32) at SDL.c:74
#6 0x04a2617c in SDL_Init (flags=3D32) at SDL.c:166
#7 0x08049722 in main (argc=3D1, argv=3D0x0) at testwin.c:32
This is SDL 1.2.8 on Fedora Core 4, radeon driver for a Radeon 9250,
xorg-x11-6.8.2-37.
I've attached a one-line patch against SDL CVS that updates the size
of the framebuffer at framebuffer map time so that the mprotect() on
unmap will be the same size. I'm not sure if this is the best
approach (i.e. one might want to retain the original value), but it
does make my SDL applications work without segfaulting.
-- Best of luck, Mark Schreiber
author | Ryan C. Gordon <icculus@icculus.org> |
---|---|
date | Sat, 19 Nov 2005 18:57:00 +0000 |
parents | fba6b67b4d60 |
children | c9b51268668f |
line wrap: on
line source
/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2004 Sam Lantinga This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with this library; if not, write to the Free Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Sam Lantinga slouken@libsdl.org */ #ifdef SAVE_RCSID static char rcsid = "@(#) $Id$"; #endif #ifndef _SDL_xbios_h #define _SDL_xbios_h #include "SDL_types.h" #include "SDL_sysvideo.h" /* Hidden "this" pointer for the video functions */ #define _THIS SDL_VideoDevice *this /* TT video modes: 2 Falcon RVB: 16 (could be *2 by adding PAL/NTSC modes) Falcon VGA: 6 ST low: 1 */ #define SDL_NUMMODES 16 typedef struct { Uint16 number; /* Video mode number */ Uint16 width; /* Size */ Uint16 height; Uint16 depth; /* bits per plane */ SDL_bool doubleline; /* Double the lines ? */ } xbiosmode_t; /* Private display data */ #define NUM_MODELISTS 2 /* 8 and 16 bits-per-pixel */ struct SDL_PrivateVideoData { long cookie_vdo; int old_video_mode; /* Old video mode before entering SDL */ void *old_video_base; /* Old pointer to screen buffer */ void *old_palette; /* Old palette */ Uint32 old_num_colors; /* Nb of colors in saved palette */ int num_modes; /* Number of xbios video modes */ xbiosmode_t *mode_list; /* List of xbios video modes */ void *screens[2]; /* Pointers to aligned screen buffer */ void *screensmem[2]; /* Pointers to screen buffer */ void *shadowscreen; /* Shadow screen for c2p conversion */ int doubleline; /* Double line mode ? */ int frame_number; /* Number of frame for double buffer */ int pitch; /* Destination line width for C2P */ int width, height; /* Screen size for centered C2P */ SDL_bool centscreen; /* Centscreen extension present ? */ SDL_Rect *SDL_modelist[NUM_MODELISTS][SDL_NUMMODES+1]; xbiosmode_t *videomodes[NUM_MODELISTS][SDL_NUMMODES+1]; }; /* _VDO cookie values */ enum { VDO_ST=0, VDO_STE, VDO_TT, VDO_F30 }; /* Monitor types */ enum { MONITOR_MONO=0, MONITOR_TV, MONITOR_VGA, MONITOR_RGB }; /* EgetShift masks */ #define ES_BANK 0x000f #define ES_MODE 0x0700 #define ES_GRAY 0x1000 #define ES_SMEAR 0x8000 /* TT shifter modes */ #define ST_LOW 0x0000 #define ST_MED 0x0100 #define ST_HIGH 0x0200 #define TT_LOW 0x0700 #define TT_MED 0x0300 #define TT_HIGH 0x0600 /* Hidden structure -> variables names */ #define SDL_modelist (this->hidden->SDL_modelist) #define XBIOS_mutex (this->hidden->mutex) #define XBIOS_cvdo (this->hidden->cookie_vdo) #define XBIOS_oldpalette (this->hidden->old_palette) #define XBIOS_oldnumcol (this->hidden->old_num_colors) #define XBIOS_oldvbase (this->hidden->old_video_base) #define XBIOS_oldvmode (this->hidden->old_video_mode) #define XBIOS_nummodes (this->hidden->num_modes) #define XBIOS_modelist (this->hidden->mode_list) #define XBIOS_screens (this->hidden->screens) #define XBIOS_screensmem (this->hidden->screensmem) #define XBIOS_shadowscreen (this->hidden->shadowscreen) #define XBIOS_videomodes (this->hidden->videomodes) #define XBIOS_doubleline (this->hidden->doubleline) #define XBIOS_fbnum (this->hidden->frame_number) #define XBIOS_pitch (this->hidden->pitch) #define XBIOS_width (this->hidden->width) #define XBIOS_height (this->hidden->height) #define XBIOS_centscreen (this->hidden->centscreen) /*--- Functions prototypes ---*/ void SDL_XBIOS_AddMode(_THIS, Uint16 modecode, Uint16 width, Uint16 height, Uint16 depth, SDL_bool flags); #endif /* _SDL_xbios_h */