view src/video/xbios/SDL_xbios_centscreen.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 d910939febfa
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/*
    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
*/

/*
	Centscreen extension definitions

	Patrice Mandin
*/

#ifndef _SDL_xbios_centscreen_h
#define _SDL_xbios_centscreen_h

#include <mint/falcon.h>	/* for trap_14_xxx macros */

#include "SDL_xbios.h"

/*--- Defines ---*/

#ifndef C_CNTS
#define C_CNTS 0x434e5453L
#endif

#define CSCREEN_ENERGYSTAR		(1<<9)
#define CSCREEN_SAVER			(1<<10)
#define CSCREEN_VIRTUAL			(1<<11)
#define CSCREEN_EXTCLOCK_CT2	(1<<12)
#define CSCREEN_EXTCLOCK		(1<<13)
#define CSCREEN_STANDARD		(1<<14)
#define CSCREEN_DEFAULT			(1<<15)

/*--- Structures ---*/

typedef struct {
	unsigned short	handle;	/* videomode handle */
	unsigned short	mode;	/* Falcon videomode code */
	unsigned short	physx;	/* visible width */
	unsigned short	physy;	/* visible height */
	unsigned short	plan;	/* bitplanes */
	unsigned short	logx;	/* virtual width */
	unsigned short	logy;	/* virtual height */
	unsigned short	eco;	/* screen saver delay */
	unsigned short	eco2;	/* energy star screen saver delay */
	unsigned short	wsize;	/* screen width (mm) */
	unsigned short	hsize;	/* screen height (mm) */
	unsigned short	dummy[21];
	unsigned char	name[32];	/* videomode name */
} __attribute__((packed)) centscreen_mode_t;

/*--- Functions prototypes ---*/

#define Vread(current_mode)	\
	(void)trap_14_wl((short)0x41,(long)(current_mode))
#define Vwrite(init_vdi, inparam, outparam)	\
	(long)trap_14_wwll((short)0x42,(short)(init_vdi),(long)(inparam),(long)(outparam))
#define Vattrib(inparam, outparam)	\
	(void)trap_14_wll((short)0x43,(long)(inparam),(long)(outparam))
#define Vcreate(inparam, outparam)	\
	(void)trap_14_wll((short)0x44,(long)(inparam),(long)(outparam))
#define Vdelete(handle)	\
	(long)trap_14_ww((short)0x45,(short)(handle))
#define Vfirst(mask,mode)	\
	(long)trap_14_wll((short)0x46,(long)(mask),(long)(mode))
#define Vnext(mask,mode)	\
	(long)trap_14_wll((short)0x47,(long)(mask),(long)(mode))
#define Vvalid(handle)	\
	(long)trap_14_ww((short)0x48,(short)(handle))
#define Vload()	\
	(long)trap_14_w((short)0x49)
#define Vsave()	\
	(long)trap_14_w((short)0x4a)
#define Vopen()	\
	(long)trap_14_w((short)0x4b)
#define Vclose()	\
	(long)trap_14_w((short)0x4c)
#define Vscroll(scrollmode)	\
	(long)trap_14_ww((short)0x4d,(short)(scrollmode))
#define Voffset()	\
	(long)trap_14_w((short)0x4e)
#define Vseek()	\
	(long)trap_14_w((short)0x4f)
#define Vlock(cmd)	\
	(long)trap_14_ww((short)0x50,(short)(cmd))
#define SetMon(montype)	\
	(long)trap_14_ww((short)0x51,(short)(montype))
#define MultiMon(cmd)	\
	(long)trap_14_ww((short)0x52,(short)(cmd))
#define VSizeComp()	\
	(long)trap_14_w((short)0x53)
#define Vsize(mode)	\
	(long)trap_14_wl((short)0x54,(long)(mode))

/*--- Functions prototypes ---*/

int SDL_XBIOS_CentscreenInit(_THIS);
void SDL_XBIOS_CentscreenSetmode(_THIS, int width, int height, int planes);
void SDL_XBIOS_CentscreenRestore(_THIS, int prev_handle);

#endif /* _SDL_xbios_centscreen_h */