Mercurial > sdl-ios-xcode
view src/cdrom/SDL_cdrom.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 | b8d311d90021 |
children | c9b51268668f |
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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 /* This is the CD-audio control API for Simple DirectMedia Layer */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include "SDL_error.h" #include "SDL_cdrom.h" #include "SDL_syscdrom.h" #if !defined(macintosh) #define CLIP_FRAMES 10 /* Some CD-ROMs won't go all the way */ #endif static int SDL_cdinitted = 0; static SDL_CD *default_cdrom; /* The system level CD-ROM control functions */ struct CDcaps SDL_CDcaps = { NULL, /* Name */ NULL, /* Open */ NULL, /* GetTOC */ NULL, /* Status */ NULL, /* Play */ NULL, /* Pause */ NULL, /* Resume */ NULL, /* Stop */ NULL, /* Eject */ NULL, /* Close */ }; int SDL_numcds; int SDL_CDROMInit(void) { int retval; SDL_numcds = 0; retval = SDL_SYS_CDInit(); if ( retval == 0 ) { SDL_cdinitted = 1; } default_cdrom = NULL; return(retval); } /* Check to see if the CD-ROM subsystem has been initialized */ static int CheckInit(int check_cdrom, SDL_CD **cdrom) { int okay; okay = SDL_cdinitted; if ( check_cdrom && (*cdrom == NULL) ) { *cdrom = default_cdrom; if ( *cdrom == NULL ) { SDL_SetError("CD-ROM not opened"); okay = 0; } } if ( ! SDL_cdinitted ) { SDL_SetError("CD-ROM subsystem not initialized"); } return(okay); } int SDL_CDNumDrives(void) { if ( ! CheckInit(0, NULL) ) { return(-1); } return(SDL_numcds); } const char *SDL_CDName(int drive) { if ( ! CheckInit(0, NULL) ) { return(NULL); } if ( drive >= SDL_numcds ) { SDL_SetError("Invalid CD-ROM drive index"); return(NULL); } if ( SDL_CDcaps.Name ) { return(SDL_CDcaps.Name(drive)); } else { return(""); } } SDL_CD *SDL_CDOpen(int drive) { struct SDL_CD *cdrom; if ( ! CheckInit(0, NULL) ) { return(NULL); } if ( drive >= SDL_numcds ) { SDL_SetError("Invalid CD-ROM drive index"); return(NULL); } cdrom = (SDL_CD *)malloc(sizeof(*cdrom)); if ( cdrom == NULL ) { SDL_OutOfMemory(); return(NULL); } memset(cdrom, 0, sizeof(*cdrom)); cdrom->id = SDL_CDcaps.Open(drive); if ( cdrom->id < 0 ) { free(cdrom); return(NULL); } default_cdrom = cdrom; return(cdrom); } CDstatus SDL_CDStatus(SDL_CD *cdrom) { CDstatus status; int i; Uint32 position; /* Check if the CD-ROM subsystem has been initialized */ if ( ! CheckInit(1, &cdrom) ) { return(CD_ERROR); } /* Get the current status of the drive */ cdrom->numtracks = 0; cdrom->cur_track = 0; cdrom->cur_frame = 0; status = SDL_CDcaps.Status(cdrom, &i); position = (Uint32)i; cdrom->status = status; /* Get the table of contents, if there's a CD available */ if ( CD_INDRIVE(status) ) { if ( SDL_CDcaps.GetTOC(cdrom) < 0 ) { status = CD_ERROR; } /* If the drive is playing, get current play position */ if ( (status == CD_PLAYING) || (status == CD_PAUSED) ) { for ( i=1; cdrom->track[i].offset <= position; ++i ) { /* Keep looking */; } #ifdef DEBUG_CDROM fprintf(stderr, "Current position: %d, track = %d (offset is %d)\n", position, i-1, cdrom->track[i-1].offset); #endif cdrom->cur_track = i-1; position -= cdrom->track[cdrom->cur_track].offset; cdrom->cur_frame = position; } } return(status); } int SDL_CDPlayTracks(SDL_CD *cdrom, int strack, int sframe, int ntracks, int nframes) { int etrack, eframe; int start, length; /* Check if the CD-ROM subsystem has been initialized */ if ( ! CheckInit(1, &cdrom) ) { return(CD_ERROR); } /* Determine the starting and ending tracks */ if ( (strack < 0) || (strack >= cdrom->numtracks) ) { SDL_SetError("Invalid starting track"); return(CD_ERROR); } if ( ! ntracks && ! nframes ) { etrack = cdrom->numtracks; eframe = 0; } else { etrack = strack+ntracks; if ( etrack == strack ) { eframe = sframe + nframes; } else { eframe = nframes; } } if ( etrack > cdrom->numtracks ) { SDL_SetError("Invalid play length"); return(CD_ERROR); } /* Skip data tracks and verify frame offsets */ while ( (strack <= etrack) && (cdrom->track[strack].type == SDL_DATA_TRACK) ) { ++strack; } if ( sframe >= (int)cdrom->track[strack].length ) { SDL_SetError("Invalid starting frame for track %d", strack); return(CD_ERROR); } while ( (etrack > strack) && (cdrom->track[etrack-1].type == SDL_DATA_TRACK) ) { --etrack; } if ( eframe > (int)cdrom->track[etrack].length ) { SDL_SetError("Invalid ending frame for track %d", etrack); return(CD_ERROR); } /* Determine start frame and play length */ start = (cdrom->track[strack].offset+sframe); length = (cdrom->track[etrack].offset+eframe)-start; #ifdef CLIP_FRAMES /* I've never seen this necessary, but xmcd does it.. */ length -= CLIP_FRAMES; /* CLIP_FRAMES == 10 */ #endif if ( length < 0 ) { return(0); } /* Play! */ #ifdef DEBUG_CDROM fprintf(stderr, "Playing %d frames at offset %d\n", length, start); #endif return(SDL_CDcaps.Play(cdrom, start, length)); } int SDL_CDPlay(SDL_CD *cdrom, int sframe, int length) { /* Check if the CD-ROM subsystem has been initialized */ if ( ! CheckInit(1, &cdrom) ) { return(CD_ERROR); } return(SDL_CDcaps.Play(cdrom, sframe, length)); } int SDL_CDPause(SDL_CD *cdrom) { CDstatus status; int retval; /* Check if the CD-ROM subsystem has been initialized */ if ( ! CheckInit(1, &cdrom) ) { return(CD_ERROR); } status = SDL_CDcaps.Status(cdrom, NULL); switch (status) { case CD_PLAYING: retval = SDL_CDcaps.Pause(cdrom); break; default: retval = 0; break; } return(retval); } int SDL_CDResume(SDL_CD *cdrom) { CDstatus status; int retval; /* Check if the CD-ROM subsystem has been initialized */ if ( ! CheckInit(1, &cdrom) ) { return(CD_ERROR); } status = SDL_CDcaps.Status(cdrom, NULL); switch (status) { case CD_PAUSED: retval = SDL_CDcaps.Resume(cdrom); default: retval = 0; break; } return(retval); } int SDL_CDStop(SDL_CD *cdrom) { CDstatus status; int retval; /* Check if the CD-ROM subsystem has been initialized */ if ( ! CheckInit(1, &cdrom) ) { return(CD_ERROR); } status = SDL_CDcaps.Status(cdrom, NULL); switch (status) { case CD_PLAYING: case CD_PAUSED: retval = SDL_CDcaps.Stop(cdrom); default: retval = 0; break; } return(retval); } int SDL_CDEject(SDL_CD *cdrom) { /* Check if the CD-ROM subsystem has been initialized */ if ( ! CheckInit(1, &cdrom) ) { return(CD_ERROR); } return(SDL_CDcaps.Eject(cdrom)); } void SDL_CDClose(SDL_CD *cdrom) { /* Check if the CD-ROM subsystem has been initialized */ if ( ! CheckInit(1, &cdrom) ) { return; } SDL_CDcaps.Close(cdrom); free(cdrom); default_cdrom = NULL; } void SDL_CDROMQuit(void) { SDL_SYS_CDQuit(); SDL_cdinitted = 0; }