Mercurial > sdl-ios-xcode
view src/video/fbcon/SDL_fbvideo.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 | b8d311d90021 |
children | 718d00094f82 |
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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 */ #ifdef SAVE_RCSID static char rcsid = "@(#) $Id$"; #endif #ifndef _SDL_fbvideo_h #define _SDL_fbvideo_h #include <sys/types.h> #include <termios.h> #include <linux/fb.h> #include "SDL_mouse.h" #include "SDL_mutex.h" #include "SDL_sysvideo.h" /* Hidden "this" pointer for the video functions */ #define _THIS SDL_VideoDevice *this /* This is the structure we use to keep track of video memory */ typedef struct vidmem_bucket { struct vidmem_bucket *prev; int used; int dirty; char *base; unsigned int size; struct vidmem_bucket *next; } vidmem_bucket; /* Private display data */ struct SDL_PrivateVideoData { int console_fd; struct fb_var_screeninfo cache_vinfo; struct fb_var_screeninfo saved_vinfo; int saved_cmaplen; __u16 *saved_cmap; int current_vt; int saved_vt; int keyboard_fd; int saved_kbd_mode; struct termios saved_kbd_termios; int mouse_fd; char *mapped_mem; int mapped_memlen; int mapped_offset; char *mapped_io; long mapped_iolen; int flip_page; char *flip_address[2]; #define NUM_MODELISTS 4 /* 8, 16, 24, and 32 bits-per-pixel */ int SDL_nummodes[NUM_MODELISTS]; SDL_Rect **SDL_modelist[NUM_MODELISTS]; vidmem_bucket surfaces; int surfaces_memtotal; int surfaces_memleft; SDL_mutex *hw_lock; void (*wait_vbl)(_THIS); void (*wait_idle)(_THIS); }; /* Old variable names */ #define console_fd (this->hidden->console_fd) #define current_vt (this->hidden->current_vt) #define saved_vt (this->hidden->saved_vt) #define keyboard_fd (this->hidden->keyboard_fd) #define saved_kbd_mode (this->hidden->saved_kbd_mode) #define saved_kbd_termios (this->hidden->saved_kbd_termios) #define mouse_fd (this->hidden->mouse_fd) #define cache_vinfo (this->hidden->cache_vinfo) #define saved_vinfo (this->hidden->saved_vinfo) #define saved_cmaplen (this->hidden->saved_cmaplen) #define saved_cmap (this->hidden->saved_cmap) #define mapped_mem (this->hidden->mapped_mem) #define mapped_memlen (this->hidden->mapped_memlen) #define mapped_offset (this->hidden->mapped_offset) #define mapped_io (this->hidden->mapped_io) #define mapped_iolen (this->hidden->mapped_iolen) #define flip_page (this->hidden->flip_page) #define flip_address (this->hidden->flip_address) #define SDL_nummodes (this->hidden->SDL_nummodes) #define SDL_modelist (this->hidden->SDL_modelist) #define surfaces (this->hidden->surfaces) #define surfaces_memtotal (this->hidden->surfaces_memtotal) #define surfaces_memleft (this->hidden->surfaces_memleft) #define hw_lock (this->hidden->hw_lock) #define wait_vbl (this->hidden->wait_vbl) #define wait_idle (this->hidden->wait_idle) /* Accelerator types that are supported by the driver, but are not necessarily in the kernel headers on the system we compile on. */ #ifndef FB_ACCEL_MATROX_MGAG400 #define FB_ACCEL_MATROX_MGAG400 26 /* Matrox G400 */ #endif #ifndef FB_ACCEL_3DFX_BANSHEE #define FB_ACCEL_3DFX_BANSHEE 31 /* 3Dfx Banshee */ #endif /* These functions are defined in SDL_fbvideo.c */ extern void FB_SavePaletteTo(_THIS, int palette_len, __u16 *area); extern void FB_RestorePaletteFrom(_THIS, int palette_len, __u16 *area); /* These are utility functions for working with video surfaces */ static __inline__ void FB_AddBusySurface(SDL_Surface *surface) { ((vidmem_bucket *)surface->hwdata)->dirty = 1; } static __inline__ int FB_IsSurfaceBusy(SDL_Surface *surface) { return ((vidmem_bucket *)surface->hwdata)->dirty; } static __inline__ void FB_WaitBusySurfaces(_THIS) { vidmem_bucket *bucket; /* Wait for graphic operations to complete */ wait_idle(this); /* Clear all surface dirty bits */ for ( bucket=&surfaces; bucket; bucket=bucket->next ) { bucket->dirty = 0; } } static __inline__ void FB_dst_to_xy(_THIS, SDL_Surface *dst, int *x, int *y) { *x = (long)((char *)dst->pixels - mapped_mem)%this->screen->pitch; *y = (long)((char *)dst->pixels - mapped_mem)/this->screen->pitch; if ( dst == this->screen ) { *x += this->offset_x; *y += this->offset_y; } } #endif /* _SDL_fbvideo_h */