Mercurial > sdl-ios-xcode
view src/cdrom/macosx/SDLOSXCAGuard.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 | 71a2648acc75 |
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 */ /* Note: This file hasn't been modified so technically we have to keep the disclaimer :-( Copyright: © Copyright 2002 Apple Computer, Inc. All rights reserved. Disclaimer: IMPORTANT: This Apple software is supplied to you by Apple Computer, Inc. ("Apple") in consideration of your agreement to the following terms, and your use, installation, modification or redistribution of this Apple software constitutes acceptance of these terms. If you do not agree with these terms, please do not use, install, modify or redistribute this Apple software. In consideration of your agreement to abide by the following terms, and subject to these terms, Apple grants you a personal, non-exclusive license, under AppleÕs copyrights in this original Apple software (the "Apple Software"), to use, reproduce, modify and redistribute the Apple Software, with or without modifications, in source and/or binary forms; provided that if you redistribute the Apple Software in its entirety and without modifications, you must retain this notice and the following text and disclaimers in all such redistributions of the Apple Software. Neither the name, trademarks, service marks or logos of Apple Computer, Inc. may be used to endorse or promote products derived from the Apple Software without specific prior written permission from Apple. Except as expressly stated in this notice, no other rights or licenses, express or implied, are granted by Apple herein, including but not limited to any patent rights that may be infringed by your derivative works or by other works in which the Apple Software may be incorporated. The Apple Software is provided by Apple on an "AS IS" basis. APPLE MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND OPERATION ALONE OR IN COMBINATION WITH YOUR PRODUCTS. IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION, MODIFICATION AND/OR DISTRIBUTION OF THE APPLE SOFTWARE, HOWEVER CAUSED AND WHETHER UNDER THEORY OF CONTRACT, TORT (INCLUDING NEGLIGENCE), STRICT LIABILITY OR OTHERWISE, EVEN IF APPLE HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /*============================================================================= CAGuard.h =============================================================================*/ #if !defined(__CAGuard_h__) #define __CAGuard_h__ //============================================================================= // Includes //============================================================================= #include <CoreAudio/CoreAudioTypes.h> #include <pthread.h> //============================================================================= // CAGuard // // This is your typical mutex with signalling implemented via pthreads. // Lock() will return true if and only if the guard is locked on that call. // A thread that already has the guard will receive 'false' if it locks it // again. Use of the stack-based CAGuard::Locker class is highly recommended // to properly manage the recursive nesting. The Wait calls with timeouts // will return true if and only if the timeout period expired. They will // return false if they receive notification any other way. //============================================================================= typedef struct S_SDLOSXCAGuard { // Construction/Destruction //public: // Actions //public: int (*Lock)(struct S_SDLOSXCAGuard *cag); void (*Unlock)(struct S_SDLOSXCAGuard *cag); int (*Try)(struct S_SDLOSXCAGuard *cag, int *outWasLocked); // returns true if lock is free, false if not void (*Wait)(struct S_SDLOSXCAGuard *cag); void (*Notify)(struct S_SDLOSXCAGuard *cag); // Implementation //protected: pthread_mutex_t mMutex; pthread_cond_t mCondVar; pthread_t mOwner; } SDLOSXCAGuard; SDLOSXCAGuard *new_SDLOSXCAGuard(void); void delete_SDLOSXCAGuard(SDLOSXCAGuard *cag); #endif