view src/cdrom/beos/SDL_syscdrom.cc @ 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
line wrap: on
line source

/*
    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

/* Functions for system-level CD-ROM audio control on BeOS
   (not completely implemented yet)
 */

#include <sys/types.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>

#include <scsi.h>
#include <Directory.h>
#include <Entry.h>
#include <Path.h>

#include "SDL_error.h"
#include "SDL_cdrom.h"
extern "C" {
#include "SDL_syscdrom.h"
}

/* Constants to help us get at the SCSI table-of-contents info */
#define CD_NUMTRACKS(toc)	toc.toc_data[3]
#define CD_TRACK(toc, track)	(&toc.toc_data[6+(track)*8])
#define CD_TRACK_N(toc, track)	CD_TRACK(toc, track)[0]
#define CD_TRACK_M(toc, track)	CD_TRACK(toc, track)[3]
#define CD_TRACK_S(toc, track)	CD_TRACK(toc, track)[4]
#define CD_TRACK_F(toc, track)	CD_TRACK(toc, track)[5]

/* Constants to help us get at the SCSI position info */
#define POS_TRACK(pos)	pos.position[6]
#define POS_ABS_M(pos)	pos.position[9]
#define POS_ABS_S(pos)	pos.position[10]
#define POS_ABS_F(pos)	pos.position[11]
#define POS_REL_M(pos)	pos.position[13]
#define POS_REL_S(pos)	pos.position[14]
#define POS_REL_F(pos)	pos.position[15]

/* The maximum number of CD-ROM drives we'll detect */
#define MAX_DRIVES	16	

/* A list of available CD-ROM drives */
static char *SDL_cdlist[MAX_DRIVES];

/* The system-dependent CD control functions */
static const char *SDL_SYS_CDName(int drive);
static int SDL_SYS_CDOpen(int drive);
static int SDL_SYS_CDGetTOC(SDL_CD *cdrom);
static CDstatus SDL_SYS_CDStatus(SDL_CD *cdrom, int *position);
static int SDL_SYS_CDPlay(SDL_CD *cdrom, int start, int length);
static int SDL_SYS_CDPause(SDL_CD *cdrom);
static int SDL_SYS_CDResume(SDL_CD *cdrom);
static int SDL_SYS_CDStop(SDL_CD *cdrom);
static int SDL_SYS_CDEject(SDL_CD *cdrom);
static void SDL_SYS_CDClose(SDL_CD *cdrom);
int try_dir(const char *directory);


/* Check a drive to see if it is a CD-ROM */
static int CheckDrive(char *drive)
{
	struct stat stbuf;
	int is_cd, cdfd;
	device_geometry info;

	/* If it doesn't exist, return -1 */
	if ( stat(drive, &stbuf) < 0 ) {
		return(-1);
	}

	/* If it does exist, verify that it's an available CD-ROM */
	is_cd = 0;
	cdfd = open(drive, 0);
	if ( cdfd >= 0 ) {
		if ( ioctl(cdfd, B_GET_GEOMETRY, &info) == B_NO_ERROR ) {
			if ( info.device_type == B_CD ) {
				is_cd = 1;
			}
		}
		close(cdfd);
	} else {
		/* This can happen when the drive is open .. (?) */;
		is_cd = 1;
	}
	return(is_cd);
}

/* Add a CD-ROM drive to our list of valid drives */
static void AddDrive(char *drive)
{
	int i;

	if ( SDL_numcds < MAX_DRIVES ) {
		/* Add this drive to our list */
		i = SDL_numcds;
		SDL_cdlist[i] = (char *)malloc(strlen(drive)+1);
		if ( SDL_cdlist[i] == NULL ) {
			SDL_OutOfMemory();
			return;
		}
		strcpy(SDL_cdlist[i], drive);
		++SDL_numcds;
#ifdef CDROM_DEBUG
  fprintf(stderr, "Added CD-ROM drive: %s\n", drive);
#endif
	}
}

/* IDE bus scanning magic */
enum {
	IDE_GET_DEVICES_INFO = B_DEVICE_OP_CODES_END + 50,
};
struct ide_ctrl_info {
	bool	ide_0_present;
	bool	ide_0_master_present;
	bool	ide_0_slave_present;
	int	ide_0_master_type;
	int	ide_0_slave_type;
	bool	ide_1_present;
	bool	ide_1_master_present;
	bool	ide_1_slave_present;
	int	ide_1_master_type;
	int	ide_1_slave_type;
};

int  SDL_SYS_CDInit(void)
{
	char *SDLcdrom;
	int raw_fd;
	struct ide_ctrl_info info;

	/* Fill in our driver capabilities */
	SDL_CDcaps.Name = SDL_SYS_CDName;
	SDL_CDcaps.Open = SDL_SYS_CDOpen;
	SDL_CDcaps.GetTOC = SDL_SYS_CDGetTOC;
	SDL_CDcaps.Status = SDL_SYS_CDStatus;
	SDL_CDcaps.Play = SDL_SYS_CDPlay;
	SDL_CDcaps.Pause = SDL_SYS_CDPause;
	SDL_CDcaps.Resume = SDL_SYS_CDResume;
	SDL_CDcaps.Stop = SDL_SYS_CDStop;
	SDL_CDcaps.Eject = SDL_SYS_CDEject;
	SDL_CDcaps.Close = SDL_SYS_CDClose;

	/* Look in the environment for our CD-ROM drive list */
	SDLcdrom = getenv("SDL_CDROM");	/* ':' separated list of devices */
	if ( SDLcdrom != NULL ) {
		char *cdpath, *delim;
		cdpath = (char *)malloc(strlen(SDLcdrom)+1);
		if ( cdpath != NULL ) {
			strcpy(cdpath, SDLcdrom);
			SDLcdrom = cdpath;
			do {
				delim = strchr(SDLcdrom, ':');
				if ( delim ) {
					*delim++ = '\0';
				}
				if ( CheckDrive(SDLcdrom) > 0 ) {
					AddDrive(SDLcdrom);
				}
				if ( delim ) {
					SDLcdrom = delim;
				} else {
					SDLcdrom = NULL;
				}
			} while ( SDLcdrom );
			free(cdpath);
		}

		/* If we found our drives, there's nothing left to do */
		if ( SDL_numcds > 0 ) {
			return(0);
		}
	}
	
	/* Scan the system for CD-ROM drives */
	try_dir("/dev/disk");
	return 0;
}


int try_dir(const char *directory)
{ 
	BDirectory dir; 
	dir.SetTo(directory); 
	if(dir.InitCheck() != B_NO_ERROR) { 
		return false; 
	} 
	dir.Rewind(); 
	BEntry entry; 
	while(dir.GetNextEntry(&entry) >= 0) { 
		BPath path; 
		const char *name; 
		entry_ref e; 
		
		if(entry.GetPath(&path) != B_NO_ERROR) 
			continue; 
		name = path.Path(); 
		
		if(entry.GetRef(&e) != B_NO_ERROR) 
			continue; 

		if(entry.IsDirectory()) { 
			if(strcmp(e.name, "floppy") == 0) 
				continue; /* ignore floppy (it is not silent)  */
			int devfd = try_dir(name);
			if(devfd >= 0)
				return devfd;
		} 
		else { 
			int devfd; 
			device_geometry g; 

			if(strcmp(e.name, "raw") != 0) 
				continue; /* ignore partitions */

			devfd = open(name, O_RDONLY); 
			if(devfd < 0) 
				continue; 

			if(ioctl(devfd, B_GET_GEOMETRY, &g, sizeof(g)) >= 0) {
				if(g.device_type == B_CD)
				{
				AddDrive(strdup(name));
				}
			}
			close(devfd);
		} 
	}
	return B_ERROR;
}


/* General ioctl() CD-ROM command function */
static int SDL_SYS_CDioctl(int index, int command, void *arg)
{
	int okay;
	int fd;

	okay = 0;
	fd = open(SDL_cdlist[index], 0);
	if ( fd >= 0 ) {
		if ( ioctl(fd, command, arg) == B_NO_ERROR ) {
			okay = 1;
		}
		close(fd);
	}
	return(okay ? 0 : -1);
}

static const char *SDL_SYS_CDName(int drive)
{
	return(SDL_cdlist[drive]);
} 

static int SDL_SYS_CDOpen(int drive)
{
	return(drive);
}

static int SDL_SYS_CDGetTOC(SDL_CD *cdrom)
{
	int i;
	scsi_toc toc;

	if ( SDL_SYS_CDioctl(cdrom->id, B_SCSI_GET_TOC, &toc) == 0 ) {
		cdrom->numtracks = CD_NUMTRACKS(toc);
		if ( cdrom->numtracks > SDL_MAX_TRACKS ) {
			cdrom->numtracks = SDL_MAX_TRACKS;
		}
		for ( i=0; i<=cdrom->numtracks; ++i ) {
			cdrom->track[i].id = CD_TRACK_N(toc, i);
			/* FIXME:  How do we tell on BeOS? */
			cdrom->track[i].type = SDL_AUDIO_TRACK;
			cdrom->track[i].offset = MSF_TO_FRAMES(
							CD_TRACK_M(toc, i),
							CD_TRACK_S(toc, i),
							CD_TRACK_F(toc, i));
			cdrom->track[i].length = 0;
			if ( i > 0 ) {
				cdrom->track[i-1].length =
						cdrom->track[i].offset-
						cdrom->track[i-1].offset;
			}
		}
		return(0);
	} else {
		return(-1);
	}
}

/* Get CD-ROM status */
static CDstatus SDL_SYS_CDStatus(SDL_CD *cdrom, int *position)
{
	CDstatus status;
	int fd;
	int cur_frame;
	scsi_position pos;

	fd = open(SDL_cdlist[cdrom->id], 0);
	cur_frame = 0;
	if ( fd >= 0 ) {
		if ( ioctl(fd, B_SCSI_GET_POSITION, &pos) == B_NO_ERROR ) {
			cur_frame = MSF_TO_FRAMES(
				POS_ABS_M(pos), POS_ABS_S(pos), POS_ABS_F(pos));
		}
		if ( ! pos.position[1] || (pos.position[1] >= 0x13) ||
			((pos.position[1] == 0x12) && (!pos.position[6])) ) {
			status = CD_STOPPED;
		} else
		if ( pos.position[1] == 0x11 ) {
			status = CD_PLAYING;
		} else {
			status = CD_PAUSED;
		}
		close(fd);
	} else {
		status = CD_TRAYEMPTY;
	}
	if ( position ) {
		*position = cur_frame;
	}
	return(status);
}

/* Start play */
static int SDL_SYS_CDPlay(SDL_CD *cdrom, int start, int length)
{
	int okay;
	int fd;
	scsi_play_position pos;

	okay = 0;
	fd = open(SDL_cdlist[cdrom->id], 0);
	if ( fd >= 0 ) {
		FRAMES_TO_MSF(start, &pos.start_m, &pos.start_s, &pos.start_f);
		FRAMES_TO_MSF(start+length, &pos.end_m, &pos.end_s, &pos.end_f);
		if ( ioctl(fd, B_SCSI_PLAY_POSITION, &pos) == B_NO_ERROR ) {
			okay = 1;
		}
		close(fd);
	}
	return(okay ? 0 : -1);
}

/* Pause play */
static int SDL_SYS_CDPause(SDL_CD *cdrom)
{
	return(SDL_SYS_CDioctl(cdrom->id, B_SCSI_PAUSE_AUDIO, 0));
}

/* Resume play */
static int SDL_SYS_CDResume(SDL_CD *cdrom)
{
	return(SDL_SYS_CDioctl(cdrom->id, B_SCSI_RESUME_AUDIO, 0));
}

/* Stop play */
static int SDL_SYS_CDStop(SDL_CD *cdrom)
{
	return(SDL_SYS_CDioctl(cdrom->id, B_SCSI_STOP_AUDIO, 0));
}

/* Eject the CD-ROM */
static int SDL_SYS_CDEject(SDL_CD *cdrom)
{
	return(SDL_SYS_CDioctl(cdrom->id, B_SCSI_EJECT, 0));
}

/* Close the CD-ROM handle */
static void SDL_SYS_CDClose(SDL_CD *cdrom)
{
	close(cdrom->id);
}

void SDL_SYS_CDQuit(void)
{
	int i;

	if ( SDL_numcds > 0 ) {
		for ( i=0; i<SDL_numcds; ++i ) {
			free(SDL_cdlist[i]);
		}
		SDL_numcds = 0;
	}
}