_cdio_linux.c

linux下的MPEG1

/*
    $Id: _cdio_linux.c,v 1.4 2006/09/26 22:18:44 dgp85 Exp $

    Copyright (C) 2001 Herbert Valerio Riedel <[e-mail]>
    Copyright (C) 2002, 2003, 2004 Rocky Bernstein <[e-mail]>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program 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 General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

/* This file contains Linux-specific code and implements low-level 
   control of the CD drive.
*/

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

static const char _rcsid[] = "$Id: _cdio_linux.c,v 1.4 2006/09/26 22:18:44 dgp85 Exp $";

#include <string.h>

#include <cdio/sector.h>
#include <cdio/util.h>
#include <cdio/types.h>
#include <cdio/scsi_mmc.h>
#include <cdio/cdtext.h>
#include "cdtext_private.h"
#include "cdio_assert.h"
#include "cdio_private.h"

#ifdef HAVE_LINUX_CDROM

#if defined(HAVE_LINUX_VERSION_H)
# include <linux/version.h>
# if LINUX_VERSION_CODE >= KERNEL_VERSION(2,2,16)
#   define __CDIO_LINUXCD_BUILD
# else
#  error "You need a kernel greater than 2.2.16 to have CDROM support"
# endif
#else 
#  error "You need <linux/version.h> to have CDROM support"
#endif

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <unistd.h>
#include <fcntl.h>
#include <mntent.h>

#include <linux/cdrom.h>
#include <scsi/scsi.h>
#include <scsi/sg.h>
#include <scsi/scsi_ioctl.h>
#include <sys/mount.h>

#include <sys/stat.h>
#include <sys/types.h>
#include <sys/ioctl.h>

typedef enum {
  _AM_NONE,
  _AM_IOCTL,
  _AM_READ_CD,
  _AM_READ_10
} access_mode_t;

typedef struct {
  /* Things common to all drivers like this. 
     This must be first. */
  generic_img_private_t gen; 

  access_mode_t access_mode;

  /* Some of the more OS specific things. */
  /* Entry info for each track, add 1 for leadout. */
  struct cdrom_tocentry  tocent[CDIO_CD_MAX_TRACKS+1]; 

  struct cdrom_tochdr    tochdr;

} _img_private_t;

/* Some ioctl() errno values which occur when the tray is empty */
#define ERRNO_TRAYEMPTY(errno)	\
	((errno == EIO) || (errno == ENOENT) || (errno == EINVAL))

/**** prototypes for static functions ****/
static bool is_cdrom_linux(const char *drive, char *mnttype);
static bool read_toc_linux (void *p_user_data);
static int  run_scsi_cmd_linux( const void *p_user_data, 
				unsigned int i_timeout,
				unsigned int i_cdb, 
				const scsi_mmc_cdb_t *p_cdb, 
				scsi_mmc_direction_t e_direction, 
				unsigned int i_buf, 
				/*in/out*/ void *p_buf );
static access_mode_t 

str_to_access_mode_linux(const char *psz_access_mode) 
{
  const access_mode_t default_access_mode = _AM_IOCTL;

  if (NULL==psz_access_mode) return default_access_mode;
  
  if (!strcmp(psz_access_mode, "IOCTL"))
    return _AM_IOCTL;
  else if (!strcmp(psz_access_mode, "READ_CD"))
    return _AM_READ_CD;
  else if (!strcmp(psz_access_mode, "READ_10"))
    return _AM_READ_10;
  else {
    cdio_warn ("unknown access type: %s. Default IOCTL used.", 
	       psz_access_mode);
    return default_access_mode;
  }
}

static char *
check_mounts_linux(const char *mtab)
{
  FILE *mntfp;
  struct mntent *mntent;
  
  mntfp = setmntent(mtab, "r");
  if ( mntfp != NULL ) {
    char *tmp;
    char *mnt_type;
    char *mnt_dev;
    
    while ( (mntent=getmntent(mntfp)) != NULL ) {
      mnt_type = malloc(strlen(mntent->mnt_type) + 1);
      if (mnt_type == NULL)
	continue;  /* maybe you'll get lucky next time. */
      
      mnt_dev = malloc(strlen(mntent->mnt_fsname) + 1);
      if (mnt_dev == NULL) {
	free(mnt_type);
	continue;
      }
      
      strcpy(mnt_type, mntent->mnt_type);
      strcpy(mnt_dev, mntent->mnt_fsname);
      
      /* Handle "supermount" filesystem mounts */
      if ( strcmp(mnt_type, "supermount") == 0 ) {
	tmp = strstr(mntent->mnt_opts, "fs=");
	if ( tmp ) {
	  free(mnt_type);
	  mnt_type = strdup(tmp + strlen("fs="));
	  if ( mnt_type ) {
	    tmp = strchr(mnt_type, ',');
	    if ( tmp ) {
	      *tmp = '\0';
	    }
	  }
	}
	tmp = strstr(mntent->mnt_opts, "dev=");
	if ( tmp ) {
	  free(mnt_dev);
	  mnt_dev = strdup(tmp + strlen("dev="));
	  if ( mnt_dev ) {
	    tmp = strchr(mnt_dev, ',');
	    if ( tmp ) {
	      *tmp = '\0';
	    }
	  }
	}
      }
      if ( strcmp(mnt_type, "iso9660") == 0 ) {
	if (is_cdrom_linux(mnt_dev, mnt_type) > 0) {
	  free(mnt_type);
	  endmntent(mntfp);
	  return mnt_dev;
	}
      }
      free(mnt_dev);
      free(mnt_type);
    }
    endmntent(mntfp);
  }
  return NULL;
}

/*!
  Return the value associated with the key "arg".
*/
static const char *
get_arg_linux (void *env, const char key[])
{
  _img_private_t *_obj = env;

  if (!strcmp (key, "source")) {
    return _obj->gen.source_name;
  } else if (!strcmp (key, "access-mode")) {
    switch (_obj->access_mode) {
    case _AM_IOCTL:
      return "ioctl";
    case _AM_READ_CD:
      return "READ_CD";
    case _AM_READ_10:
      return "READ_10";
    case _AM_NONE:
      return "no access method";
    }
  } 
  return NULL;
}

#undef USE_LINUX_CAP
#ifdef USE_LINUX_CAP
/*!
  Return the the kind of drive capabilities of device.

  Note: string is malloc'd so caller should free() then returned
  string when done with it.

 */
static void
get_drive_cap_linux (const void *p_user_data,
		     /*out*/ cdio_drive_read_cap_t  *p_read_cap,
		     /*out*/ cdio_drive_write_cap_t *p_write_cap,
		     /*out*/ cdio_drive_misc_cap_t  *p_misc_cap)
{
  const _img_private_t *p_env = p_user_data;
  int32_t i_drivetype;

  i_drivetype = ioctl (p_env->gen.fd, CDROM_GET_CAPABILITY, CDSL_CURRENT);

  if (i_drivetype < 0) {
    *p_read_cap  = CDIO_DRIVE_CAP_ERROR;
    *p_write_cap = CDIO_DRIVE_CAP_ERROR;
    *p_misc_cap  = CDIO_DRIVE_CAP_ERROR;
    return;
  }
  
  *p_read_cap  = 0;
  *p_write_cap = 0;
  *p_misc_cap  = 0;

  /* Reader */
  if (i_drivetype & CDC_PLAY_AUDIO) 
    *p_read_cap  |= CDIO_DRIVE_CAP_READ_AUDIO;
  if (i_drivetype & CDC_CD_R) 
    *p_read_cap  |= CDIO_DRIVE_CAP_READ_CD_R;
  if (i_drivetype & CDC_CD_RW) 
    *p_read_cap  |= CDIO_DRIVE_CAP_READ_CD_RW;
  if (i_drivetype & CDC_DVD) 
    *p_read_cap  |= CDIO_DRIVE_CAP_READ_DVD_ROM;

  /* Writer */
  if (i_drivetype & CDC_CD_RW) 
    *p_read_cap  |= CDIO_DRIVE_CAP_WRITE_CD_RW;
  if (i_drivetype & CDC_DVD_R) 
    *p_read_cap  |= CDIO_DRIVE_CAP_WRITE_DVD_R;
  if (i_drivetype & CDC_DVD_RAM) 
    *p_read_cap  |= CDIO_DRIVE_CAP_WRITE_DVD_RAM;

  /* Misc */
  if (i_drivetype & CDC_CLOSE_TRAY) 
    *p_misc_cap  |= CDIO_DRIVE_CAP_MISC_CLOSE_TRAY;
  if (i_drivetype & CDC_OPEN_TRAY) 
    *p_misc_cap  |= CDIO_DRIVE_CAP_MISC_EJECT;
  if (i_drivetype & CDC_LOCK) 
    *p_misc_cap  |= CDIO_DRIVE_CAP_MISC_LOCK;
  if (i_drivetype & CDC_SELECT_SPEED) 
    *p_misc_cap  |= CDIO_DRIVE_CAP_MISC_SELECT_SPEED;
  if (i_drivetype & CDC_SELECT_DISC) 
    *p_misc_cap  |= CDIO_DRIVE_CAP_MISC_SELECT_DISC;
  if (i_drivetype & CDC_MULTI_SESSION) 
    *p_misc_cap  |= CDIO_DRIVE_CAP_MISC_MULTI_SESSION;
  if (i_drivetype & CDC_MEDIA_CHANGED) 
    *p_misc_cap  |= CDIO_DRIVE_CAP_MISC_MEDIA_CHANGED;
  if (i_drivetype & CDC_RESET) 
    *p_misc_cap  |= CDIO_DRIVE_CAP_MISC_RESET;
}
#endif

/*!
  Return the media catalog number MCN.

  Note: string is malloc'd so caller should free() then returned
  string when done with it.

 */
static char *
get_mcn_linux (const void *p_user_data) {

  struct cdrom_mcn mcn;
  const _img_private_t *p_env = p_user_data;
  memset(&mcn, 0, sizeof(mcn));
  if (ioctl(p_env->gen.fd, CDROM_GET_MCN, &mcn) != 0)
    return NULL;
  return strdup(mcn.medium_catalog_number);
}

/*!  
  Get format of track. 
*/
static track_format_t
get_track_format_linux(void *p_user_data, track_t i_track) 
{
  _img_private_t *p_env = p_user_data;
  
  if ( !p_env ) return TRACK_FORMAT_ERROR;

  if (!p_env->gen.toc_init) read_toc_linux (p_user_data) ;

  if (i_track > (p_env->gen.i_tracks+p_env->gen.i_first_track) 
      || i_track < p_env->gen.i_first_track)
    return TRACK_FORMAT_ERROR;

  i_track -= p_env->gen.i_first_track;

  /* This is pretty much copied from the "badly broken" cdrom_count_tracks
     in linux/cdrom.c.
   */
  if (p_env->tocent[i_track].cdte_ctrl & CDIO_CDROM_DATA_TRACK) {
    if (p_env->tocent[i_track].cdte_format == CDIO_CDROM_CDI_TRACK)
      return TRACK_FORMAT_CDI;
    else if (p_env->tocent[i_track].cdte_format == CDIO_CDROM_XA_TRACK)
      return TRACK_FORMAT_XA;
    else
      return TRACK_FORMAT_DATA;
  } else
    return TRACK_FORMAT_AUDIO;
  
}

/*!
  Return true if we have XA data (green, mode2 form1) or
  XA data (green, mode2 form2). That is track begins:
  sync - header - subheader
  12     4      -  8

  FIXME: there's gotta be a better design for this and get_track_format?
*/
static bool
get_track_green_linux(void *p_user_data, track_t i_track) 
{
  _img_private_t *p_env = p_user_data;
  
  if (!p_env->gen.toc_init) read_toc_linux (p_user_data) ;

  if (i_track >= (p_env->gen.i_tracks+p_env->gen.i_first_track) 
      || i_track < p_env->gen.i_first_track)
    return false;

  i_track -= p_env->gen.i_first_track;

  /* FIXME: Dunno if this is the right way, but it's what 
     I was using in cd-info for a while.
   */
  return ((p_env->tocent[i_track].cdte_ctrl & 2) != 0);
}

/*!  
  Return the starting MSF (minutes/secs/frames) for track number
  track_num in obj.  Track numbers usually start at something 
  greater than 0, usually 1.

  The "leadout" track is specified either by
  using i_track LEADOUT_TRACK or the total tracks+1.
  False is returned if there is no track entry.
*/
static bool
get_track_msf_linux(void *p_user_data, track_t i_track, msf_t *msf)
{
  _img_private_t *p_env = p_user_data;

  if (NULL == msf) return false;

  if (!p_env->gen.toc_init) read_toc_linux (p_user_data) ;

  if (i_track == CDIO_CDROM_LEADOUT_TRACK) 
    i_track = p_env->gen.i_tracks + p_env->gen.i_first_track;

  if (i_track > (p_env->gen.i_tracks+p_env->gen.i_first_track) 
      || i_track < p_env->gen.i_first_track) {
    return false;
  } else {
    struct cdrom_msf0  *msf0= 
      &p_env->tocent[i_track-p_env->gen.i_first_track].cdte_addr.msf;
    msf->m = cdio_to_bcd8(msf0->minute);
    msf->s = cdio_to_bcd8(msf0->second);
    msf->f = cdio_to_bcd8(msf0->frame);
    return true;
  }
}