Mercurial > sdl-ios-xcode
annotate src/thread/beos/SDL_syssem.c @ 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 | ab0154afe938 |
| children | c9b51268668f |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 SDL - Simple DirectMedia Layer | |
|
769
b8d311d90021
Updated copyright information for 2004 (Happy New Year!)
Sam Lantinga <slouken@libsdl.org>
parents:
297
diff
changeset
|
3 Copyright (C) 1997-2004 Sam Lantinga |
| 0 | 4 |
| 5 This library is free software; you can redistribute it and/or | |
| 6 modify it under the terms of the GNU Library General Public | |
| 7 License as published by the Free Software Foundation; either | |
| 8 version 2 of the License, or (at your option) any later version. | |
| 9 | |
| 10 This library is distributed in the hope that it will be useful, | |
| 11 but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 13 Library General Public License for more details. | |
| 14 | |
| 15 You should have received a copy of the GNU Library General Public | |
| 16 License along with this library; if not, write to the Free | |
| 17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
| 18 | |
| 19 Sam Lantinga | |
|
252
e8157fcb3114
Updated the source with the correct e-mail address
Sam Lantinga <slouken@libsdl.org>
parents:
0
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|
20 slouken@libsdl.org |
| 0 | 21 */ |
| 22 | |
| 23 #ifdef SAVE_RCSID | |
| 24 static char rcsid = | |
| 25 "@(#) $Id$"; | |
| 26 #endif | |
| 27 | |
| 28 /* Semaphores in the BeOS environment */ | |
| 29 | |
| 30 #include <be/kernel/OS.h> | |
| 31 | |
| 32 #include "SDL_error.h" | |
| 33 #include "SDL_thread.h" | |
| 34 | |
| 35 | |
| 36 struct SDL_semaphore { | |
| 37 sem_id id; | |
| 38 }; | |
| 39 | |
| 40 /* Create a counting semaphore */ | |
| 41 SDL_sem *SDL_CreateSemaphore(Uint32 initial_value) | |
| 42 { | |
| 43 SDL_sem *sem; | |
| 44 | |
| 45 sem = (SDL_sem *)malloc(sizeof(*sem)); | |
| 46 if ( sem ) { | |
| 47 sem->id = create_sem(initial_value, "SDL semaphore"); | |
| 48 if ( sem->id < B_NO_ERROR ) { | |
| 49 SDL_SetError("create_sem() failed"); | |
| 50 free(sem); | |
| 51 sem = NULL; | |
| 52 } | |
| 53 } else { | |
| 54 SDL_OutOfMemory(); | |
| 55 } | |
| 56 return(sem); | |
| 57 } | |
| 58 | |
| 59 /* Free the semaphore */ | |
| 60 void SDL_DestroySemaphore(SDL_sem *sem) | |
| 61 { | |
| 62 if ( sem ) { | |
| 63 if ( sem->id >= B_NO_ERROR ) { | |
| 64 delete_sem(sem->id); | |
| 65 } | |
| 66 free(sem); | |
| 67 } | |
| 68 } | |
| 69 | |
| 70 int SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout) | |
| 71 { | |
| 72 int32 val; | |
| 73 int retval; | |
| 74 | |
| 75 if ( ! sem ) { | |
| 76 SDL_SetError("Passed a NULL semaphore"); | |
| 77 return -1; | |
| 78 } | |
| 79 | |
| 80 tryagain: | |
| 81 if ( timeout == SDL_MUTEX_MAXWAIT ) { | |
| 82 val = acquire_sem(sem->id); | |
| 83 } else { | |
| 84 timeout *= 1000; /* BeOS uses a timeout in microseconds */ | |
| 85 val = acquire_sem_etc(sem->id, 1, B_RELATIVE_TIMEOUT, timeout); | |
| 86 } | |
| 87 switch (val) { | |
| 88 case B_INTERRUPTED: | |
| 89 goto tryagain; | |
| 90 case B_NO_ERROR: | |
| 91 retval = 0; | |
| 92 break; | |
|
1146
ab0154afe938
Date: Sat, 17 Sep 2005 13:38:49 +0200
Ryan C. Gordon <icculus@icculus.org>
parents:
769
diff
changeset
|
93 case B_TIMED_OUT: |
|
ab0154afe938
Date: Sat, 17 Sep 2005 13:38:49 +0200
Ryan C. Gordon <icculus@icculus.org>
parents:
769
diff
changeset
|
94 retval = SDL_MUTEX_TIMEDOUT; |
|
ab0154afe938
Date: Sat, 17 Sep 2005 13:38:49 +0200
Ryan C. Gordon <icculus@icculus.org>
parents:
769
diff
changeset
|
95 break; |
|
ab0154afe938
Date: Sat, 17 Sep 2005 13:38:49 +0200
Ryan C. Gordon <icculus@icculus.org>
parents:
769
diff
changeset
|
96 case B_WOULD_BLOCK: |
|
ab0154afe938
Date: Sat, 17 Sep 2005 13:38:49 +0200
Ryan C. Gordon <icculus@icculus.org>
parents:
769
diff
changeset
|
97 retval = SDL_MUTEX_TIMEDOUT; |
|
ab0154afe938
Date: Sat, 17 Sep 2005 13:38:49 +0200
Ryan C. Gordon <icculus@icculus.org>
parents:
769
diff
changeset
|
98 break; |
| 0 | 99 default: |
| 100 SDL_SetError("acquire_sem() failed"); | |
| 101 retval = -1; | |
| 102 break; | |
| 103 } | |
| 104 | |
| 105 return retval; | |
| 106 } | |
| 107 | |
| 108 int SDL_SemTryWait(SDL_sem *sem) | |
| 109 { | |
| 110 return SDL_SemWaitTimeout(sem, 0); | |
| 111 } | |
| 112 | |
| 113 int SDL_SemWait(SDL_sem *sem) | |
| 114 { | |
| 115 return SDL_SemWaitTimeout(sem, SDL_MUTEX_MAXWAIT); | |
| 116 } | |
| 117 | |
| 118 /* Returns the current count of the semaphore */ | |
| 119 Uint32 SDL_SemValue(SDL_sem *sem) | |
| 120 { | |
| 121 int32 count; | |
| 122 Uint32 value; | |
| 123 | |
| 124 value = 0; | |
| 125 if ( sem ) { | |
| 126 get_sem_count(sem->id, &count); | |
| 127 if ( count > 0 ) { | |
| 128 value = (Uint32)count; | |
| 129 } | |
| 130 } | |
| 131 return value; | |
| 132 } | |
| 133 | |
| 134 /* Atomically increases the semaphore's count (not blocking) */ | |
| 135 int SDL_SemPost(SDL_sem *sem) | |
| 136 { | |
| 137 if ( ! sem ) { | |
| 138 SDL_SetError("Passed a NULL semaphore"); | |
| 139 return -1; | |
| 140 } | |
| 141 | |
| 142 if ( release_sem(sem->id) != B_NO_ERROR ) { | |
| 143 SDL_SetError("release_sem() failed"); | |
| 144 return -1; | |
| 145 } | |
| 146 return 0; | |
| 147 } |