view include/SDL_types.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 bc0b95b02235
children 173c063d4f55
line wrap: on
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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

/* General data types used by the SDL library */

#ifndef _SDL_types_h
#define _SDL_types_h

/* The number of elements in a table */
#define SDL_TABLESIZE(table)	(sizeof(table)/sizeof(table[0]))

/* Basic data types */
typedef enum {
	SDL_FALSE = 0,
	SDL_TRUE  = 1
} SDL_bool;

#ifdef H_MMBASIC /* mmbasic.h (Tru64 MME) */
/* Some of the basic types are already defined in mmbasic.h */
typedef signed char	Sint8;
typedef signed short	Sint16;
typedef signed int	Sint32;
#else
typedef unsigned char	Uint8;
typedef signed char	Sint8;
typedef unsigned short	Uint16;
typedef signed short	Sint16;
typedef unsigned int	Uint32;
typedef signed int	Sint32;
#endif

/* Figure out how to support 64-bit datatypes */
#if !defined(__STRICT_ANSI__)
#ifdef __osf__ /* Tru64 */
#define SDL_HAS_64BIT_TYPE	long
#elif defined(__GNUC__) || defined(__MWERKS__) || defined(__SUNPRO_C) || defined(__DECC)
#define SDL_HAS_64BIT_TYPE	long long
#elif defined(_MSC_VER) /* VC++ */
#define SDL_HAS_64BIT_TYPE	__int64
#endif
#endif /* !__STRICT_ANSI__ */

/* The 64-bit type isn't available on EPOC/Symbian OS */
#ifdef __SYMBIAN32__
#undef SDL_HAS_64BIT_TYPE
#endif

/* The 64-bit datatype isn't supported on all platforms */
#ifdef SDL_HAS_64BIT_TYPE
#ifndef H_MMBASIC
typedef unsigned SDL_HAS_64BIT_TYPE Uint64;
#endif
typedef SDL_HAS_64BIT_TYPE Sint64;
#else
/* This is really just a hack to prevent the compiler from complaining */
typedef struct {
	Uint32 hi;
	Uint32 lo;
} Uint64, Sint64;
#endif

/* Make sure the types really have the right sizes */
#define SDL_COMPILE_TIME_ASSERT(name, x)               \
       typedef int SDL_dummy_ ## name[(x) * 2 - 1]

SDL_COMPILE_TIME_ASSERT(uint8, sizeof(Uint8) == 1);
SDL_COMPILE_TIME_ASSERT(sint8, sizeof(Sint8) == 1);
SDL_COMPILE_TIME_ASSERT(uint16, sizeof(Uint16) == 2);
SDL_COMPILE_TIME_ASSERT(sint16, sizeof(Sint16) == 2);
SDL_COMPILE_TIME_ASSERT(uint32, sizeof(Uint32) == 4);
SDL_COMPILE_TIME_ASSERT(sint32, sizeof(Sint32) == 4);
SDL_COMPILE_TIME_ASSERT(uint64, sizeof(Uint64) == 8);
SDL_COMPILE_TIME_ASSERT(sint64, sizeof(Sint64) == 8);

/* Check to make sure enums are the size of ints, for structure packing.
   For both Watcom C/C++ and Borland C/C++ the compiler option that makes
   enums having the size of an int must be enabled.
   This is "-b" for Borland C/C++ and "-ei" for Watcom C/C++ (v11).
*/
/* Enable enums always int in CodeWarrior (for MPW use "-enum int") */
#ifdef __MWERKS__
#pragma enumsalwaysint on
#endif

typedef enum {
	DUMMY_ENUM_VALUE
} SDL_DUMMY_ENUM;

SDL_COMPILE_TIME_ASSERT(enum, sizeof(SDL_DUMMY_ENUM) == sizeof(int));

#undef SDL_COMPILE_TIME_ASSERT

/* General keyboard/mouse state definitions */
enum { SDL_PRESSED = 0x01, SDL_RELEASED = 0x00 };

#endif