Mercurial > sdl-ios-xcode
view src/audio/SDL_audiodev.c @ 4158:96ce26f24b01 SDL-1.2
Date: Sun, 7 Sep 2008 15:17:00 +0200
From: c2woody@gmx.net
Subject: [SDL] SDL 1.2 doube free/pointer zeroing missing
Hello,
this is about a crash/debug breakage for the current SDL 1.2
source tree (today's svn checkout, same problem in 1.2.13 and
before as far as relevant).
In some places memory is free()d but the associated pointer
is not zeroed, leading to for example double free()s.
For me this happened because SDL_StopEventThread() was executed
twice (during restart of the subsystems), once for the close
down in SDL_VideoQuit() and once at the startup, right at the
beginning of SDL_StartEventLoop(). Thus the code
SDL_DestroyMutex(SDL_EventQ.lock);
(see SDL_events.c) was called twice and executed the SDL_free(mutex);
twice as well, leading to a crash (msvc 64bit for which it was noticed).
I've tried to check all other occurrences of SDL_free and similar
code in msvc, see the attached patch (udiff against revision 4082).
Non-windows only codepaths have neither been checked nor touched.
Comments/ideas welcome.
Attached patch: NULLifies some pointers after they have been free()d.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Wed, 12 Nov 2008 17:23:40 +0000 |
parents | 12b6d331d82a |
children | 782fd950bd46 c121d94672cb a1b03ba2fcd0 |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2006 Sam Lantinga This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA Sam Lantinga slouken@libsdl.org */ #include "SDL_config.h" /* Get the name of the audio device we use for output */ #if SDL_AUDIO_DRIVER_BSD || SDL_AUDIO_DRIVER_OSS || SDL_AUDIO_DRIVER_SUNAUDIO #include <fcntl.h> #include <sys/types.h> #include <sys/stat.h> #include "SDL_stdinc.h" #include "SDL_audiodev_c.h" #ifndef _PATH_DEV_DSP #if defined(__NETBSD__) || defined(__OPENBSD__) #define _PATH_DEV_DSP "/dev/audio" #else #define _PATH_DEV_DSP "/dev/dsp" #endif #endif #ifndef _PATH_DEV_DSP24 #define _PATH_DEV_DSP24 "/dev/sound/dsp" #endif #ifndef _PATH_DEV_AUDIO #define _PATH_DEV_AUDIO "/dev/audio" #endif int SDL_OpenAudioPath(char *path, int maxlen, int flags, int classic) { const char *audiodev; int audio_fd; char audiopath[1024]; /* Figure out what our audio device is */ if ( ((audiodev=SDL_getenv("SDL_PATH_DSP")) == NULL) && ((audiodev=SDL_getenv("AUDIODEV")) == NULL) ) { if ( classic ) { audiodev = _PATH_DEV_AUDIO; } else { struct stat sb; /* Added support for /dev/sound/\* in Linux 2.4 */ if ( ((stat("/dev/sound", &sb) == 0) && S_ISDIR(sb.st_mode)) && ((stat(_PATH_DEV_DSP24, &sb) == 0) && S_ISCHR(sb.st_mode)) ) { audiodev = _PATH_DEV_DSP24; } else { audiodev = _PATH_DEV_DSP; } } } audio_fd = open(audiodev, flags, 0); /* If the first open fails, look for other devices */ if ( (audio_fd < 0) && (SDL_strlen(audiodev) < (sizeof(audiopath)-3)) ) { int exists, instance; struct stat sb; instance = 1; do { /* Don't use errno ENOENT - it may not be thread-safe */ SDL_snprintf(audiopath, SDL_arraysize(audiopath), "%s%d", audiodev, instance++); exists = 0; if ( stat(audiopath, &sb) == 0 ) { exists = 1; audio_fd = open(audiopath, flags, 0); } } while ( exists && (audio_fd < 0) ); audiodev = audiopath; } if ( path != NULL ) { SDL_strlcpy(path, audiodev, maxlen); path[maxlen-1] = '\0'; } return(audio_fd); } #elif SDL_AUDIO_DRIVER_PAUD /* Get the name of the audio device we use for output */ #include <sys/types.h> #include <sys/stat.h> #include "SDL_stdinc.h" #include "SDL_audiodev_c.h" #ifndef _PATH_DEV_DSP #define _PATH_DEV_DSP "/dev/%caud%c/%c" #endif char devsettings[][3] = { { 'p', '0', '1' }, { 'p', '0', '2' }, { 'p', '0', '3' }, { 'p', '0', '4' }, { 'p', '1', '1' }, { 'p', '1', '2' }, { 'p', '1', '3' }, { 'p', '1', '4' }, { 'p', '2', '1' }, { 'p', '2', '2' }, { 'p', '2', '3' }, { 'p', '2', '4' }, { 'p', '3', '1' }, { 'p', '3', '2' }, { 'p', '3', '3' }, { 'p', '3', '4' }, { 'b', '0', '1' }, { 'b', '0', '2' }, { 'b', '0', '3' }, { 'b', '0', '4' }, { 'b', '1', '1' }, { 'b', '1', '2' }, { 'b', '1', '3' }, { 'b', '1', '4' }, { 'b', '2', '1' }, { 'b', '2', '2' }, { 'b', '2', '3' }, { 'b', '2', '4' }, { 'b', '3', '1' }, { 'b', '3', '2' }, { 'b', '3', '3' }, { 'b', '3', '4' }, { '\0', '\0', '\0' } }; static int OpenUserDefinedDevice(char *path, int maxlen, int flags) { const char *audiodev; int audio_fd; /* Figure out what our audio device is */ if ((audiodev=SDL_getenv("SDL_PATH_DSP")) == NULL) { audiodev=SDL_getenv("AUDIODEV"); } if ( audiodev == NULL ) { return -1; } audio_fd = open(audiodev, flags, 0); if ( path != NULL ) { SDL_strlcpy(path, audiodev, maxlen); path[maxlen-1] = '\0'; } return audio_fd; } int SDL_OpenAudioPath(char *path, int maxlen, int flags, int classic) { struct stat sb; int audio_fd; char audiopath[1024]; int cycle; audio_fd = OpenUserDefinedDevice(path,maxlen,flags); if ( audio_fd != -1 ) { return audio_fd; } cycle = 0; while( devsettings[cycle][0] != '\0' ) { SDL_snprintf( audiopath, SDL_arraysize(audiopath), _PATH_DEV_DSP, devsettings[cycle][0], devsettings[cycle][1], devsettings[cycle][2]); if ( stat(audiopath, &sb) == 0 ) { audio_fd = open(audiopath, flags, 0); if ( audio_fd > 0 ) { if ( path != NULL ) { SDL_strlcpy( path, audiopath, maxlen ); } return audio_fd; } } } return -1; } #endif /* Audio driver selection */