/*
    $Id: iso9660_fs.c,v 1.35 2006/03/17 22:36:31 rocky Exp $

    Copyright (C) 2001 Herbert Valerio Riedel <hvr@gnu.org>
    Copyright (C) 2003, 2004, 2005, 2006 Rocky Bernstein <rocky@panix.com>

    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., 51 Franklin Street, Fifth Floor, Boston, MA
    02110-1301 USA.
*/
/* iso9660 filesystem-based routines */

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#ifdef HAVE_STRING_H
# include <string.h>
#endif

#ifdef HAVE_ERRNO_H
# include <errno.h>
#endif

#ifdef HAVE_ICONV
# include <iconv.h>
#endif

#ifdef HAVE_LANGINFO_CODESET
#include <langinfo.h>
#endif

#include <cdio/cdio.h>
#include <cdio/bytesex.h>
#include <cdio/iso9660.h>
#include <cdio/util.h>

/* Private headers */
#include "cdio_assert.h"
#include "_cdio_stdio.h"
#include "cdio_private.h"

#include <stdio.h>

static const char _rcsid[] = "$Id: iso9660_fs.c,v 1.35 2006/03/17 22:36:31 rocky Exp $";

/* Implementation of iso9660_t type */
struct _iso9660_s {
  CdioDataSource_t *stream; /* Stream pointer */
  bool_3way_t b_xa;         /* true if has XA attributes. */
  bool_3way_t b_mode2;      /* true if has mode 2, false for mode 1. */
  uint8_t  i_joliet_level;  /* 0 = no Joliet extensions.
			       1-3: Joliet level. */
  iso9660_pvd_t pvd;      
  iso9660_svd_t svd;      
  iso_extension_mask_t iso_extension_mask; /* What extensions we
					      tolerate. */
  uint32_t i_datastart;     /* Usually 0 when i_framesize is ISO_BLOCKSIZE.
			       This is the normal condition. But in a fuzzy 
			       read we may be reading a CD-image
			       and not a true ISO 9660 image this might be
			       CDIO_CD_SYNC_SIZE
                            */ 
  uint32_t i_framesize;     /* Usually ISO_BLOCKSIZE (2048), but in a
			      fuzzy read, we may be reading a CD-image
			      and not a true ISO 9660 image this might
			      be CDIO_CD_FRAMESIZE_RAW (2352) or
			      M2RAW_SECTOR_SIZE (2336).
                            */ 
  int i_fuzzy_offset;       /* Adjustment in bytes to make ISO_STANDARD_ID
			       ("CD001") come out as ISO_PVD_SECTOR
			       (frame 16).  Normally this should be 0
			       for an ISO 9660 image, but if one is
			       say reading a BIN/CUE or cdrdao BIN/TOC
			       without having the CUE or TOC and
			       trying to extract an ISO-9660
			       filesystem inside that it may be
			       different.
			     */
};

static long int iso9660_seek_read_framesize (const iso9660_t *p_iso, 
					     void *ptr, lsn_t start, 
					     long int size, 
					     uint16_t i_framesize);

/* Adjust the p_iso's i_datastart, i_byte_offset and i_framesize 
   based on whether we find a frame header or not.
*/
static void 
adjust_fuzzy_pvd( iso9660_t *p_iso )
{
  long int i_byte_offset;
  
  if (!p_iso) return;

  i_byte_offset = (ISO_PVD_SECTOR * p_iso->i_framesize) 
    + p_iso->i_fuzzy_offset + p_iso->i_datastart;

  /* If we have a raw 2352-byte frame then we should expect to see a sync
     frame and a header. 
   */
  if (CDIO_CD_FRAMESIZE_RAW == p_iso->i_framesize) {
    const int pre_user_data=CDIO_CD_SYNC_SIZE +  CDIO_CD_HEADER_SIZE 
      + CDIO_CD_SUBHEADER_SIZE;
    char buf[pre_user_data];
    
    i_byte_offset -= pre_user_data;
    
    if ( DRIVER_OP_SUCCESS != cdio_stream_seek (p_iso->stream, i_byte_offset, 
						SEEK_SET) )
      return;
    if (sizeof(buf) == cdio_stream_read (p_iso->stream, buf, sizeof(buf), 1)) {
      /* Does the sector frame header suggest Mode 1 format? */
      if (!memcmp(CDIO_SECTOR_SYNC_HEADER, buf+CDIO_CD_SUBHEADER_SIZE, 
		  CDIO_CD_SYNC_SIZE)) {
	if (buf[14+CDIO_CD_SUBHEADER_SIZE] != 0x16) {
	  cdio_warn ("Expecting the PVD sector header MSF to be 0x16, is: %x", 
		     buf[14]);
	}
	if (buf[15+CDIO_CD_SUBHEADER_SIZE] != 0x1) {
	  cdio_warn ("Expecting the PVD sector mode to be Mode 1 is: %x", 
		     buf[15]);
	}
	p_iso->b_mode2 = nope;
	p_iso->b_xa = nope;
      } else if (!memcmp(CDIO_SECTOR_SYNC_HEADER, buf, CDIO_CD_SYNC_SIZE)) {
	/* Frame header indicates Mode 2 Form 1*/
	if (buf[14] != 0x16) {
	  cdio_warn ("Expecting the PVD sector header MSF to be 0x16, is: %x", 
		     buf[14]);
	}
	if (buf[15] != 0x2) {
	  cdio_warn ("Expecting the PVD sector mode to be Mode 2 is: %x", 
		     buf[15]);
	}
	p_iso->b_mode2 = yep;
	/* Do do: check Mode 2 Form 2? */
      } else {
	  /* Has no frame header */
	  p_iso->i_framesize = M2RAW_SECTOR_SIZE;
	  p_iso->i_fuzzy_offset = (CDIO_CD_FRAMESIZE_RAW - M2RAW_SECTOR_SIZE) 
	    * ISO_PVD_SECTOR + p_iso->i_fuzzy_offset + p_iso->i_datastart;
	  p_iso->i_datastart = 0;
	}
    }
  }

  
}

/*!
  Open an ISO 9660 image for reading in either fuzzy mode or not.
*/
static iso9660_t *
iso9660_open_ext_private (const char *psz_path,
			  iso_extension_mask_t iso_extension_mask,
			  uint16_t i_fuzz, bool b_fuzzy)
{
  iso9660_t *p_iso = (iso9660_t *) calloc(1, sizeof(iso9660_t)) ;
  bool b_have_superblock;

  if (!p_iso) return NULL;
  
  p_iso->stream = cdio_stdio_new( psz_path );
  if (NULL == p_iso->stream) 
    goto error;

  p_iso->i_framesize = ISO_BLOCKSIZE;

  b_have_superblock = (b_fuzzy) 
    ? iso9660_ifs_fuzzy_read_superblock(p_iso, iso_extension_mask, i_fuzz)
    : iso9660_ifs_read_superblock(p_iso, iso_extension_mask) ;

  if ( ! b_have_superblock ) goto error;
  
  /* Determine if image has XA attributes. */
  
  p_iso->b_xa = strncmp ((char *) &(p_iso->pvd) + ISO_XA_MARKER_OFFSET, 
			 ISO_XA_MARKER_STRING,
			 sizeof (ISO_XA_MARKER_STRING)) 
    ? nope : yep;
  
  p_iso->iso_extension_mask = iso_extension_mask;
  return p_iso;

 error:
  free(p_iso);
  return NULL;
}

/*!
  Open an ISO 9660 image for reading. Maybe in the future we will have
  a mode. NULL is returned on error.
*/
iso9660_t *
iso9660_open (const char *psz_path /*, mode*/)
{
  return iso9660_open_ext(psz_path, ISO_EXTENSION_NONE);
}

/*!
  Open an ISO 9660 image for reading. Maybe in the future we will have
  a mode. NULL is returned on error.
*/
iso9660_t *
iso9660_open_ext (const char *psz_path,
		  iso_extension_mask_t iso_extension_mask)
{
  return iso9660_open_ext_private(psz_path, iso_extension_mask, 0, false);
}


/*!
  Open an ISO 9660 image for reading. Maybe in the future we will have
  a mode. NULL is returned on error.
*/
iso9660_t *
iso9660_open_fuzzy (const char *psz_path, uint16_t i_fuzz /*, mode*/)
{
  return iso9660_open_fuzzy_ext(psz_path, ISO_EXTENSION_NONE, i_fuzz);
}

/*!
  Open an ISO 9660 image for reading. Maybe in the future we will have
  a mode. NULL is returned on error.
*/
iso9660_t *
iso9660_open_fuzzy_ext (const char *psz_path,
			iso_extension_mask_t iso_extension_mask,
			uint16_t i_fuzz)
{
  return iso9660_open_ext_private(psz_path, iso_extension_mask, i_fuzz,
				  true);
}

/*!
  Close previously opened ISO 9660 image.
  True is unconditionally returned. If there was an error false would
  be returned.
*/
bool 
iso9660_close (iso9660_t *p_iso)
{
  if (NULL != p_iso) {
    cdio_stdio_destroy(p_iso->stream);
    free(p_iso);
  }
  return true;
}

static bool
check_pvd (const iso9660_pvd_t *p_pvd, cdio_log_level_t log_level) 
{
  if ( ISO_VD_PRIMARY != from_711(p_pvd->type) ) {
    cdio_log (log_level, "unexpected PVD type %d", p_pvd->type);
    return false;
  }
  
  if (strncmp (p_pvd->id, ISO_STANDARD_ID, strlen (ISO_STANDARD_ID)))
    {
      cdio_log (log_level, "unexpected ID encountered (expected `"
		ISO_STANDARD_ID "', got `%.5s'", p_pvd->id);
      return false;
    }
  return true;
}

#ifdef HAVE_JOLIET
static bool
ucs2be_to_locale(ICONV_CONST char *psz_ucs2be,  size_t i_inlen, 
		 char **p_psz_out,  size_t i_outlen)
{

  iconv_t ic = 
#if defined(HAVE_LANGINFO_CODESET)
    iconv_open(nl_langinfo(CODESET), "UCS-2BE");
#else 
    iconv_open("ASCII", "UCS-2BE");
#endif

  int rc;
  char *psz_buf = NULL;
  char *psz_buf2;
  int i_outlen_max = i_outlen;
  int i_outlen_actual;

  if (-1 == (size_t) ic) {
#if defined(HAVE_LANGINFO_CODESET)
    cdio_info("Failed to get conversion table for locale, trying ASCII");
    ic = iconv_open("ASCII", "UCS-2BE");
    if (-1 == (size_t) ic) {
      cdio_info("Failed to get conversion table for ASCII too");
      return false;
    }
#else 
    cdio_info("Failed to get conversion table for locale");
    return false;
#endif
  }
  
  psz_buf = (char *) realloc(psz_buf, i_outlen);
  psz_buf2 = psz_buf;
  if (!psz_buf) {
    /* XXX: report out of memory error */
    goto error;
  }
  rc = iconv(ic, &psz_ucs2be, &i_inlen, &psz_buf2, &i_outlen);
  iconv_close(ic);
  if ((rc == -1) && (errno != E2BIG)) {
    /* conversion failed */
    goto error;
  }
  i_outlen_actual = i_outlen_max - i_outlen;
  *p_psz_out = malloc(i_outlen_actual + 1);
  memcpy(*p_psz_out, psz_buf, i_outlen_actual);
  *(*p_psz_out + i_outlen_actual) = '\0';
  free(psz_buf);
  return true;
 error:
  free(psz_buf);
  *p_psz_out = NULL; 
  return false;
}
#endif /*HAVE_JOLIET*/

/*!  
  Return the application ID.  NULL is returned in psz_app_id if there
  is some problem in getting this.
*/
bool
iso9660_ifs_get_application_id(iso9660_t *p_iso, 
			       /*out*/ char **p_psz_app_id)
{
  if (!p_iso) {
    *p_psz_app_id = NULL;
    return false;
  }

#ifdef HAVE_JOLIET  
  if (p_iso->i_joliet_level) {
    /* TODO: check that we haven't reached the maximum size.
       If we have, perhaps we've truncated and if we can get 
       longer results *and* have the same character using
       the PVD, do that.
     */
    if ( ucs2be_to_locale(p_iso->svd.application_id, 
			  ISO_MAX_APPLICATION_ID, 
			  p_psz_app_id, 
			  ISO_MAX_APPLICATION_ID))
      return true;
  }
#endif /*HAVE_JOLIET*/ 
  *p_psz_app_id = iso9660_get_application_id( &(p_iso->pvd) );
  return *p_psz_app_id != NULL && strlen(*p_psz_app_id);
}

/*!  
  Return the Joliet level recognaized for p_iso.
*/
uint8_t iso9660_ifs_get_joliet_level(iso9660_t *p_iso)
{
  if (!p_iso) return 0;
  return p_iso->i_joliet_level;
}

/*!
   Return a string containing the preparer id with trailing
   blanks removed.
*/
bool
iso9660_ifs_get_preparer_id(iso9660_t *p_iso,
			/*out*/ char **p_psz_preparer_id)
{
  if (!p_iso) {
    *p_psz_preparer_id = NULL;
    return false;
  }

#ifdef HAVE_JOLIET  
  if (p_iso->i_joliet_level) {
    /* TODO: check that we haven't reached the maximum size.
       If we have, perhaps we've truncated and if we can get 
       longer results *and* have the same character using
       the PVD, do that.
     */
    if ( ucs2be_to_locale(p_iso->svd.preparer_id, ISO_MAX_PREPARER_ID, 
			  p_psz_preparer_id, ISO_MAX_PREPARER_ID) )
      return true;
  }
#endif /*HAVE_JOLIET*/
  *p_psz_preparer_id = iso9660_get_preparer_id( &(p_iso->pvd) );
  return *p_psz_preparer_id != NULL && strlen(*p_psz_preparer_id);
}

/*!
   Return a string containing the PVD's publisher id with trailing
   blanks removed.
*/
bool iso9660_ifs_get_publisher_id(iso9660_t *p_iso,
                                  /*out*/ char **p_psz_publisher_id)
{
  if (!p_iso) {
    *p_psz_publisher_id = NULL;
    return false;
  }

#ifdef HAVE_JOLIET  
  if (p_iso->i_joliet_level) {
    /* TODO: check that we haven't reached the maximum size.
       If we have, perhaps we've truncated and if we can get 
       longer results *and* have the same character using
       the PVD, do that.
     */
    if( ucs2be_to_locale(p_iso->svd.publisher_id, ISO_MAX_PUBLISHER_ID, 
			 p_psz_publisher_id, ISO_MAX_PUBLISHER_ID) )
      return true;
  }
#endif /*HAVE_JOLIET*/
  *p_psz_publisher_id = iso9660_get_publisher_id( &(p_iso->pvd) );
  return *p_psz_publisher_id != NULL && strlen(*p_psz_publisher_id);
}


/*!
   Return a string containing the PVD's publisher id with trailing
   blanks removed.
*/
bool iso9660_ifs_get_system_id(iso9660_t *p_iso,
			       /*out*/ char **p_psz_system_id)
{
  if (!p_iso) {
    *p_psz_system_id = NULL;
    return false;
  }

#ifdef HAVE_JOLIET  
  if (p_iso->i_joliet_level) {
    /* TODO: check that we haven't reached the maximum size.
       If we have, perhaps we've truncated and if we can get 
       longer results *and* have the same character using
       the PVD, do that.
     */
    if ( ucs2be_to_locale(p_iso->svd.system_id, ISO_MAX_SYSTEM_ID, 
			  p_psz_system_id, ISO_MAX_SYSTEM_ID) )
      return true;
  }
#endif /*HAVE_JOLIET*/
  *p_psz_system_id = iso9660_get_system_id( &(p_iso->pvd) );
  return *p_psz_system_id != NULL && strlen(*p_psz_system_id);
}


/*!
   Return a string containing the PVD's publisher id with trailing
   blanks removed.
*/
bool iso9660_ifs_get_volume_id(iso9660_t *p_iso,
			       /*out*/ char **p_psz_volume_id)
{
  if (!p_iso) {
    *p_psz_volume_id = NULL;
    return false;
  }

#ifdef HAVE_JOLIET  
  if (p_iso->i_joliet_level) {
    /* TODO: check that we haven't reached the maximum size.
       If we have, perhaps we've truncated and if we can get 
       longer results *and* have the same character using
       the PVD, do that.
     */
    if ( ucs2be_to_locale(p_iso->svd.volume_id, ISO_MAX_VOLUME_ID, 
			  p_psz_volume_id, ISO_MAX_VOLUME_ID) )
      return true;
  }
#endif /* HAVE_JOLIET */
  *p_psz_volume_id = iso9660_get_volume_id( &(p_iso->pvd) );
  return *p_psz_volume_id != NULL && strlen(*p_psz_volume_id);
}


/*!
   Return a string containing the PVD's publisher id with trailing
   blanks removed.
*/
bool iso9660_ifs_get_volumeset_id(iso9660_t *p_iso,
				  /*out*/ char **p_psz_volumeset_id)
{
  if (!p_iso) {
    *p_psz_volumeset_id = NULL;
    return false;
  }

#ifdef HAVE_JOLIET  
  if (p_iso->i_joliet_level) {
    /* TODO: check that we haven't reached the maximum size.
       If we have, perhaps we've truncated and if we can get 
       longer results *and* have the same character using
       the PVD, do that.
     */
    if ( ucs2be_to_locale(p_iso->svd.volume_set_id, 
			  ISO_MAX_VOLUMESET_ID, 
			  p_psz_volumeset_id, 
			  ISO_MAX_VOLUMESET_ID) )
      return true;
  }
#endif /*HAVE_JOLIET*/
  *p_psz_volumeset_id = iso9660_get_volumeset_id( &(p_iso->pvd) );
  return *p_psz_volumeset_id != NULL && strlen(*p_psz_volumeset_id);
}


/*!
  Read the Primary Volume Descriptor for an ISO 9660 image.
  True is returned if read, and false if there was an error.
*/
static bool 
iso9660_ifs_read_pvd_loglevel (const iso9660_t *p_iso, 
			       /*out*/ iso9660_pvd_t *p_pvd, 
			       cdio_log_level_t log_level)
{
  if (0 == iso9660_iso_seek_read (p_iso, p_pvd, ISO_PVD_SECTOR, 1)) {
    cdio_log ( log_level, "error reading PVD sector (%d)", ISO_PVD_SECTOR );
    return false;
  }
  return check_pvd(p_pvd, log_level);
}

/*!
  Read the Primary Volume Descriptor for an ISO 9660 image.
  True is returned if read, and false if there was an error.
*/
bool 
iso9660_ifs_read_pvd (const iso9660_t *p_iso, /*out*/ iso9660_pvd_t *p_pvd)
{
  return iso9660_ifs_read_pvd_loglevel(p_iso, p_pvd, CDIO_LOG_WARN);
}


/*!
  Read the Super block of an ISO 9660 image. This is the 
  Primary Volume Descriptor (PVD) and perhaps a Supplemental Volume 
  Descriptor if (Joliet) extensions are acceptable.
*/
bool 
iso9660_ifs_read_superblock (iso9660_t *p_iso, 
			     iso_extension_mask_t iso_extension_mask)
{
  iso9660_svd_t *p_svd;  /* Secondary volume descriptor. */
  
  if (!p_iso || !iso9660_ifs_read_pvd(p_iso, &(p_iso->pvd)))
    return false;

  p_svd = &(p_iso->svd);
  p_iso->i_joliet_level = 0;

  if (0 != iso9660_iso_seek_read (p_iso, p_svd, ISO_PVD_SECTOR+1, 1)) {
    if ( ISO_VD_SUPPLEMENTARY == from_711(p_svd->type) ) {
      if (p_svd->escape_sequences[0] == 0x25 
	  && p_svd->escape_sequences[1] == 0x2f) {
	switch (p_svd->escape_sequences[2]) {
	case 0x40:
	  if (iso_extension_mask & ISO_EXTENSION_JOLIET_LEVEL1) 
	    p_iso->i_joliet_level = 1;
	  break;
	case 0x43:
	  if (iso_extension_mask & ISO_EXTENSION_JOLIET_LEVEL2) 
	    p_iso->i_joliet_level = 2;
	  break;
	case 0x45:
	  if (iso_extension_mask & ISO_EXTENSION_JOLIET_LEVEL3) 
	    p_iso->i_joliet_level = 3;
	  break;
	default:
	  cdio_info("Supplementary Volume Descriptor found, but not Joliet");
	}
	if (p_iso->i_joliet_level > 0) {
	  cdio_info("Found Extension: Joliet Level %d", p_iso->i_joliet_level);
	}
      }
    }
  }
  
  return true;
}

/*!
  Read the Super block of an ISO 9660 image but determine framesize
  and datastart and a possible additional offset. Generally here we are
  not reading an ISO 9660 image but a CD-Image which contains an ISO 9660
  filesystem.
*/
bool 
iso9660_ifs_fuzzy_read_superblock (iso9660_t *p_iso, 
				   iso_extension_mask_t iso_extension_mask,
				   uint16_t i_fuzz)
{
  /* Got some work to do to find ISO_STANDARD_ID ("CD001") */
  unsigned int i;
  
  for (i=0; i<i_fuzz; i++) {
    unsigned int j;
    char *pvd = NULL;

    for (j = 0; j <= 1; j++ ) {
      lsn_t lsn;
      uint16_t k;
      const uint16_t framesizes[] = { ISO_BLOCKSIZE, CDIO_CD_FRAMESIZE_RAW, 
				      M2RAW_SECTOR_SIZE } ;

      /* We don't need to loop over a zero offset twice*/
      if (0==i && j)
	continue;
      
      lsn = (j) ? ISO_PVD_SECTOR - i : ISO_PVD_SECTOR + i;
      
      for (k=0; k < 3; k++) {
	char *p, *q;
	char frame[CDIO_CD_FRAMESIZE_RAW] = {'\0',};
	p_iso->i_framesize = framesizes[k];
	p_iso->i_datastart = (ISO_BLOCKSIZE == framesizes[k]) ? 
			      0 : CDIO_CD_SYNC_SIZE;
	p_iso->i_fuzzy_offset = 0;
	if (0 == iso9660_seek_read_framesize (p_iso, frame, lsn, 1, 
					      p_iso->i_framesize)) {
	  return false;
	}

	q = memchr(frame, 'C', p_iso->i_framesize);
	for ( p=q; p && p < frame + p_iso->i_framesize ; p=q+1 ) {
	  q = memchr(p, 'C', p_iso->i_framesize - (p - frame));
	  if ( !q || (pvd = strstr(q, ISO_STANDARD_ID)) )
	    break;
	}
	
	if (pvd) {
	  /* Yay! Found something */
	  p_iso->i_fuzzy_offset = (pvd - frame - 1) - 
	    ((ISO_PVD_SECTOR-lsn)*p_iso->i_framesize) ;
	  /* But is it *really* a PVD? */
	  if ( iso9660_ifs_read_pvd_loglevel(p_iso, &(p_iso->pvd), 
					     CDIO_LOG_DEBUG) ) {
	    adjust_fuzzy_pvd(p_iso);
	    return true;
	  }
	  
	}
      }
    }
  }
  return false;
}

  
/*!
  Read the Primary Volume Descriptor for of CD.
*/
bool 
iso9660_fs_read_pvd(const CdIo_t *p_cdio, /*out*/ iso9660_pvd_t *p_pvd)
{
  /* A bit of a hack, we'll assume track 1 contains ISO_PVD_SECTOR.*/
  char buf[CDIO_CD_FRAMESIZE_RAW] = { 0, };
  driver_return_code_t driver_return = 
    cdio_read_data_sectors (p_cdio, buf, ISO_PVD_SECTOR, ISO_BLOCKSIZE, 1);

  if (DRIVER_OP_SUCCESS != driver_return) {
    cdio_warn ("error reading PVD sector (%d) error %d", ISO_PVD_SECTOR,
	       driver_return);
    return false;
  }

  /* The size of a PVD or SVD is smaller than a sector. So we
     allocated a bigger block above (buf) and now we'll copy just
     the part we need to save.
   */
  cdio_assert (sizeof(buf) >= sizeof (iso9660_pvd_t));
  memcpy(p_pvd, buf, sizeof(iso9660_pvd_t));
  
  return check_pvd(p_pvd, CDIO_LOG_WARN);
}


/*!
  Read the Super block of an ISO 9660 image. This is the 
  Primary Volume Descriptor (PVD) and perhaps a Supplemental Volume 
  Descriptor if (Joliet) extensions are acceptable.
*/
bool 
iso9660_fs_read_superblock (CdIo_t *p_cdio, 
			    iso_extension_mask_t iso_extension_mask)
{
  if (!p_cdio) return false;
  
  {
    generic_img_private_t *p_env = (generic_img_private_t *) p_cdio->env;
    iso9660_pvd_t         *p_pvd = &(p_env->pvd);
    iso9660_svd_t         *p_svd = &(p_env->svd);
    char buf[CDIO_CD_FRAMESIZE_RAW] = { 0, };
    driver_return_code_t driver_return;

    if ( !iso9660_fs_read_pvd(p_cdio, p_pvd) )
      return false;
    
    p_env->i_joliet_level = 0;
    
    driver_return = 
      cdio_read_data_sectors ( p_cdio, buf, ISO_PVD_SECTOR+1, ISO_BLOCKSIZE,
			       1 );

    if (DRIVER_OP_SUCCESS == driver_return) {
      /* The size of a PVD or SVD is smaller than a sector. So we
	 allocated a bigger block above (buf) and now we'll copy just
	 the part we need to save.
      */
      cdio_assert (sizeof(buf) >= sizeof (iso9660_svd_t));
      memcpy(p_svd, buf, sizeof(iso9660_svd_t));
  
      if ( ISO_VD_SUPPLEMENTARY == from_711(p_svd->type) ) {
	if (p_svd->escape_sequences[0] == 0x25 
	    && p_svd->escape_sequences[1] == 0x2f) {
	  switch (p_svd->escape_sequences[2]) {
	  case 0x40:
	    if (iso_extension_mask & ISO_EXTENSION_JOLIET_LEVEL1) 
	      p_env->i_joliet_level = 1;
	    break;
	  case 0x43:
	    if (iso_extension_mask & ISO_EXTENSION_JOLIET_LEVEL2) 
	      p_env->i_joliet_level = 2;
	    break;
	  case 0x45:
	    if (iso_extension_mask & ISO_EXTENSION_JOLIET_LEVEL3) 
	      p_env->i_joliet_level = 3;
	    break;
	  default:
	    cdio_info("Supplementary Volume Descriptor found, but not Joliet");
	  }
	  if (p_env->i_joliet_level > 0) {
	    cdio_info("Found Extension: Joliet Level %d", 
		      p_env->i_joliet_level);
	  }
	}
      }
    }
  }

  return true;
}

/*!
  Seek to a position and then read n blocks. Size read is returned.
*/
static long int 
iso9660_seek_read_framesize (const iso9660_t *p_iso, void *ptr, 
			     lsn_t start, long int size, 
			     uint16_t i_framesize)
{
  long int ret;
  long int i_byte_offset;
  
  if (!p_iso) return 0;
  i_byte_offset = (start * p_iso->i_framesize) + p_iso->i_fuzzy_offset 
    + p_iso->i_datastart;

  ret = cdio_stream_seek (p_iso->stream, i_byte_offset, SEEK_SET);
  if (ret!=0) return 0;
  return cdio_stream_read (p_iso->stream, ptr, i_framesize, size);
}

/*!
  Seek to a position and then read n blocks. Size read is returned.
*/
long int 
iso9660_iso_seek_read (const iso9660_t *p_iso, void *ptr, lsn_t start, 
		       long int size)
{
  return iso9660_seek_read_framesize(p_iso, ptr, start, size, ISO_BLOCKSIZE);
}



static iso9660_stat_t *
_iso9660_dir_to_statbuf (iso9660_dir_t *p_iso9660_dir, bool_3way_t b_xa, 
			 uint8_t i_joliet_level)
{
  uint8_t dir_len= iso9660_get_dir_len(p_iso9660_dir);
  iso711_t i_fname;
  unsigned int stat_len;
  iso9660_stat_t *p_stat;

  if (!dir_len) return NULL;

  i_fname  = from_711(p_iso9660_dir->filename_len);

  /* .. string in statbuf is one longer than in p_iso9660_dir's listing '\1' */
  stat_len      = sizeof(iso9660_stat_t)+i_fname+2;

  p_stat          = calloc(1, stat_len);
  p_stat->type    = (p_iso9660_dir->file_flags & ISO_DIRECTORY) 
    ? _STAT_DIR : _STAT_FILE;
  p_stat->lsn     = from_733 (p_iso9660_dir->extent);
  p_stat->size    = from_733 (p_iso9660_dir->size);
  p_stat->secsize = _cdio_len2blocks (p_stat->size, ISO_BLOCKSIZE);
  p_stat->rr.b3_rock = dunno; /*FIXME should do based on mask */
  p_stat->b_xa    = false; 

  {
    char rr_fname[256] = "";

    int  i_rr_fname = 
#ifdef HAVE_ROCK
      get_rock_ridge_filename(p_iso9660_dir, rr_fname, p_stat);
#else
      0;
#endif
    
    if (i_rr_fname > 0) {
      if (i_rr_fname > i_fname) {
	/* realloc gives valgrind errors */
	iso9660_stat_t *p_stat_new = 
	  calloc(1, sizeof(iso9660_stat_t)+i_rr_fname+2);
	memcpy(p_stat_new, p_stat, stat_len);
	free(p_stat);
	p_stat = p_stat_new;
      }
      strncpy(p_stat->filename, rr_fname, i_rr_fname+1);
    } else {
      if ('\0' == p_iso9660_dir->filename[0] && 1 == i_fname)
	strncpy (p_stat->filename, ".", sizeof("."));
      else if ('\1' == p_iso9660_dir->filename[0] && 1 == i_fname)
	strncpy (p_stat->filename, "..", sizeof(".."));
#ifdef HAVE_JOLIET
      else if (i_joliet_level) {
	int i_inlen = i_fname;
	int i_outlen = (i_inlen / 2);
	char *p_psz_out = NULL;
	ucs2be_to_locale(p_iso9660_dir->filename, i_inlen, &p_psz_out, 
			 i_outlen);
	strncpy(p_stat->filename, p_psz_out, i_fname);
	free(p_psz_out);
      }
#endif /*HAVE_JOLIET*/
      else {
	strncpy (p_stat->filename, p_iso9660_dir->filename, i_fname);
      }
    }
  }
  

  iso9660_get_dtime(&(p_iso9660_dir->recording_time), true, &(p_stat->tm));

  if (dir_len < sizeof (iso9660_dir_t)) {
    free(p_stat->rr.psz_symlink);
    free(p_stat);
    return NULL;
  }
  

  {
    int su_length = iso9660_get_dir_len(p_iso9660_dir) 
      - sizeof (iso9660_dir_t);
    su_length -= i_fname;
    
    if (su_length % 2)
      su_length--;
    
    if (su_length < 0 || su_length < sizeof (iso9660_xa_t))
      return p_stat;
    
    if (nope == b_xa) {
      return p_stat;
    } else {
      iso9660_xa_t *xa_data = 
	(void *) (((char *) p_iso9660_dir)  
		  + (iso9660_get_dir_len(p_iso9660_dir) - su_length));
      cdio_log_level_t loglevel = (yep == b_xa) 
	? CDIO_LOG_WARN : CDIO_LOG_INFO;
      
      if (xa_data->signature[0] != 'X' 
	  || xa_data->signature[1] != 'A')
	{
	  cdio_log (loglevel, 
		    "XA signature not found in ISO9660's system use area;"
		     " ignoring XA attributes for this file entry.");
	  cdio_debug ("%d %d %d, '%c%c' (%d, %d)", 
		      iso9660_get_dir_len(p_iso9660_dir), 
		      i_fname,
		      su_length,
		      xa_data->signature[0], xa_data->signature[1],
		      xa_data->signature[0], xa_data->signature[1]);
	  return p_stat;
	}
      p_stat->b_xa = true;
      p_stat->xa   = *xa_data;
    }
  }
  return p_stat;
    
}

/*!
  Return the directory name stored in the iso9660_dir_t

  A string is allocated: the caller must deallocate.
 */
char *
iso9660_dir_to_name (const iso9660_dir_t *iso9660_dir)
{
  char namebuf[256] = { 0, };
  uint8_t len=iso9660_get_dir_len(iso9660_dir);

  if (!len) return NULL;

  cdio_assert (len >= sizeof (iso9660_dir_t));

  /* (iso9660_dir->file_flags & ISO_DIRECTORY) */
  
  if (iso9660_dir->filename[0] == '\0')
    strncpy (namebuf, ".", sizeof("."));
  else if (iso9660_dir->filename[0] == '\1')
    strncpy (namebuf, "..", sizeof(".."));
  else
    strncpy (namebuf, iso9660_dir->filename, iso9660_dir->filename_len);

  return strdup (namebuf);
}

/* 
   Return a pointer to a ISO 9660 stat buffer or NULL if there's an error
*/
static iso9660_stat_t *
_fs_stat_root (CdIo_t *p_cdio)
{

  if (!p_cdio) return NULL;
  
  {
    iso_extension_mask_t iso_extension_mask = ISO_EXTENSION_ALL;
    generic_img_private_t *p_env = (generic_img_private_t *) p_cdio->env;
    iso9660_dir_t *p_iso9660_dir;
    iso9660_stat_t *p_stat;
    bool_3way_t b_xa;

    if (!p_env->i_joliet_level)
      iso_extension_mask &= ~ISO_EXTENSION_JOLIET;
    
    /* FIXME try also with Joliet.*/
    if ( !iso9660_fs_read_superblock (p_cdio, iso_extension_mask) ) {
      cdio_warn("Could not read ISO-9660 Superblock.");
      return NULL;
    }

    switch(cdio_get_discmode(p_cdio)) {
    case CDIO_DISC_MODE_CD_XA: 
      b_xa = yep;
      break;
    case CDIO_DISC_MODE_CD_DATA: 
      b_xa = nope;
      break;
    default: 
      b_xa = dunno;
    }

#ifdef HAVE_JOLIET    
    p_iso9660_dir = p_env->i_joliet_level 
      ? &(p_env->svd.root_directory_record) 
      : &(p_env->pvd.root_directory_record) ;
#else
    p_iso9660_dir = &(p_env->pvd.root_directory_record) ;
#endif
    
    p_stat = _iso9660_dir_to_statbuf (p_iso9660_dir, b_xa, 
				      p_env->i_joliet_level);
    return p_stat;
  }
  
}

static iso9660_stat_t *
_ifs_stat_root (iso9660_t *p_iso)
{
  iso9660_stat_t *p_stat;
  iso9660_dir_t *p_iso9660_dir;

#ifdef HAVE_JOLIET
  p_iso9660_dir = p_iso->i_joliet_level 
    ? &(p_iso->svd.root_directory_record)
    : &(p_iso->pvd.root_directory_record) ;
#else 
  p_iso9660_dir = &(p_iso->pvd.root_directory_record) ;
#endif
  
  p_stat = _iso9660_dir_to_statbuf (p_iso9660_dir, p_iso->b_xa,
				    p_iso->i_joliet_level);
  return p_stat;
}

static iso9660_stat_t *
_fs_stat_traverse (const CdIo_t *p_cdio, const iso9660_stat_t *_root, 
		   char **splitpath)
{
  unsigned offset = 0;
  uint8_t *_dirbuf = NULL;
  iso9660_stat_t *p_stat;
  generic_img_private_t *p_env = (generic_img_private_t *) p_cdio->env;

  if (!splitpath[0])
    {
      unsigned int len=sizeof(iso9660_stat_t) + strlen(_root->filename)+1;
      p_stat = calloc(1, len);
      memcpy(p_stat, _root, len);
      return p_stat;
    }

  if (_root->type == _STAT_FILE)
    return NULL;

  cdio_assert (_root->type == _STAT_DIR);

  if (_root->size != ISO_BLOCKSIZE * _root->secsize)
    {
      cdio_warn ("bad size for ISO9660 directory (%ud) should be (%lu)!",
		 (unsigned) _root->size, 
		 (unsigned long int) ISO_BLOCKSIZE * _root->secsize);
    }
  
  _dirbuf = calloc(1, _root->secsize * ISO_BLOCKSIZE);

  if (cdio_read_data_sectors (p_cdio, _dirbuf, _root->lsn, ISO_BLOCKSIZE, 
			      _root->secsize))
      return NULL;
  
  while (offset < (_root->secsize * ISO_BLOCKSIZE))
    {
      iso9660_dir_t *p_iso9660_dir = (void *) &_dirbuf[offset];
      iso9660_stat_t *p_stat;
      int cmp;

      if (!iso9660_get_dir_len(p_iso9660_dir))
	{
	  offset++;
	  continue;
	}
      
      p_stat = _iso9660_dir_to_statbuf (p_iso9660_dir, dunno, 
					p_env->i_joliet_level);

      cmp = strcmp(splitpath[0], p_stat->filename);

      if ( 0 != cmp && 0 == p_env->i_joliet_level && yep != p_stat->rr.b3_rock ) {
	char *trans_fname = NULL;
	unsigned int i_trans_fname=strlen(p_stat->filename);
	int trans_len;
	
	if (i_trans_fname) {
	  trans_fname = calloc(1, i_trans_fname+1);
	  if (!trans_fname) {
	    cdio_warn("can't allocate %lu bytes", 
		      (long unsigned int) strlen(p_stat->filename));
	    return NULL;
	  }
	  trans_len = iso9660_name_translate_ext(p_stat->filename, trans_fname,
						 p_env->i_joliet_level);
	  cmp = strcmp(splitpath[0], trans_fname);
	  free(trans_fname);
	}
      }
      
      if (!cmp) {
	iso9660_stat_t *ret_stat 
	  = _fs_stat_traverse (p_cdio, p_stat, &splitpath[1]);
	free(p_stat->rr.psz_symlink);
	free(p_stat);
	free (_dirbuf);
	return ret_stat;
      }

      free(p_stat->rr.psz_symlink);
      free(p_stat);
	  
      offset += iso9660_get_dir_len(p_iso9660_dir);
    }

  cdio_assert (offset == (_root->secsize * ISO_BLOCKSIZE));
  
  /* not found */
  free (_dirbuf);
  return NULL;
}

static iso9660_stat_t *
_fs_iso_stat_traverse (iso9660_t *p_iso, const iso9660_stat_t *_root, 
		       char **splitpath)
{
  unsigned offset = 0;
  uint8_t *_dirbuf = NULL;
  int ret;

  if (!splitpath[0])
    {
      iso9660_stat_t *p_stat;
      unsigned int len=sizeof(iso9660_stat_t) + strlen(_root->filename)+1;
      p_stat = calloc(1, len);
      memcpy(p_stat, _root, len);
      return p_stat;
    }

  if (_root->type == _STAT_FILE)
    return NULL;

  cdio_assert (_root->type == _STAT_DIR);

  if (_root->size != ISO_BLOCKSIZE * _root->secsize)
    {
      cdio_warn ("bad size for ISO9660 directory (%ud) should be (%lu)!",
		 (unsigned) _root->size, 
		 (unsigned long int) ISO_BLOCKSIZE * _root->secsize);
    }
  
  _dirbuf = calloc(1, _root->secsize * ISO_BLOCKSIZE);

  ret = iso9660_iso_seek_read (p_iso, _dirbuf, _root->lsn, _root->secsize);
  if (ret!=ISO_BLOCKSIZE*_root->secsize) return NULL;
  
  while (offset < (_root->secsize * ISO_BLOCKSIZE))
    {
      iso9660_dir_t *p_iso9660_dir = (void *) &_dirbuf[offset];
      iso9660_stat_t *p_stat;
      int cmp;

      if (!iso9660_get_dir_len(p_iso9660_dir))
	{
	  offset++;
	  continue;
	}
      
      p_stat = _iso9660_dir_to_statbuf (p_iso9660_dir, p_iso->b_xa, 
					p_iso->i_joliet_level);

      cmp = strcmp(splitpath[0], p_stat->filename);

      if ( 0 != cmp && 0 == p_iso->i_joliet_level 
	   && yep != p_stat->rr.b3_rock ) {
	char *trans_fname = malloc(strlen(p_stat->filename)+1);
	int trans_len;
	
	if (trans_fname == NULL) {
	  cdio_warn("can't allocate %lu bytes", 
		    (long unsigned int) strlen(p_stat->filename));
	  return NULL;
	}
	trans_len = iso9660_name_translate_ext(p_stat->filename, trans_fname, 
					       p_iso->i_joliet_level);
	cmp = strcmp(splitpath[0], trans_fname);
	free(trans_fname);
      }
      
      if (!cmp) {
	iso9660_stat_t *ret_stat 
	  = _fs_iso_stat_traverse (p_iso, p_stat, &splitpath[1]);
	free(p_stat->rr.psz_symlink);
	free(p_stat);
	free (_dirbuf);
	return ret_stat;
      }

      free(p_stat->rr.psz_symlink);
      free(p_stat);
	  
      offset += iso9660_get_dir_len(p_iso9660_dir);
    }

  cdio_assert (offset == (_root->secsize * ISO_BLOCKSIZE));
  
  /* not found */
  free (_dirbuf);
  return NULL;
}

/*!
  Get file status for psz_path into stat. NULL is returned on error.
 */
iso9660_stat_t *
iso9660_fs_stat (CdIo_t *p_cdio, const char psz_path[])
{
  iso9660_stat_t *p_root;
  char **p_psz_splitpath;
  iso9660_stat_t *p_stat;

  if (!p_cdio)   return NULL;
  if (!psz_path) return NULL;

  p_root = _fs_stat_root (p_cdio);

  if (!p_root)   return NULL;

  p_psz_splitpath = _cdio_strsplit (psz_path, '/');
  p_stat = _fs_stat_traverse (p_cdio, p_root, p_psz_splitpath);
  free(p_root);
  _cdio_strfreev (p_psz_splitpath);

  return p_stat;
}

/*!
  Get file status for psz_path into stat. NULL is returned on error.
  pathname version numbers in the ISO 9660
  name are dropped, i.e. ;1 is removed and if level 1 ISO-9660 names
  are lowercased.
 */
iso9660_stat_t *
iso9660_fs_stat_translate (CdIo_t *p_cdio, const char psz_path[], 
			   bool b_mode2)
{
  iso9660_stat_t *p_root;
  char **p_psz_splitpath;
  iso9660_stat_t *p_stat;

  if (!p_cdio)  return NULL;
  if (psz_path) return NULL;

  p_root = _fs_stat_root (p_cdio);
  if (!p_root) return NULL;

  p_psz_splitpath = _cdio_strsplit (psz_path, '/');
  p_stat = _fs_stat_traverse (p_cdio, p_root, p_psz_splitpath);
  free(p_root);
  _cdio_strfreev (p_psz_splitpath);

  return p_stat;
}

/*!
  Get file status for psz_path into stat. NULL is returned on error.
 */
iso9660_stat_t *
iso9660_ifs_stat (iso9660_t *p_iso, const char psz_path[])
{
  iso9660_stat_t *p_root;
  char **splitpath;
  iso9660_stat_t *stat;

  if (!p_iso)    return NULL;
  if (!psz_path) return NULL;

  p_root = _ifs_stat_root (p_iso);
  if (!p_root) return NULL;

  splitpath = _cdio_strsplit (psz_path, '/');
  stat = _fs_iso_stat_traverse (p_iso, p_root, splitpath);
  free(p_root);
  _cdio_strfreev (splitpath);

  return stat;
}

/*!
  Get file status for psz_path into stat. NULL is returned on error.
  pathname version numbers in the ISO 9660
  name are dropped, i.e. ;1 is removed and if level 1 ISO-9660 names
  are lowercased.
 */
iso9660_stat_t *
iso9660_ifs_stat_translate (iso9660_t *p_iso, const char psz_path[])
{
  iso9660_stat_t *p_root;
  char **p_psz_splitpath;
  iso9660_stat_t *p_stat;

  if (!p_iso)    return NULL;
  if (!psz_path) return NULL;

  p_root = _ifs_stat_root (p_iso);
  if (NULL == p_root) return NULL;

  p_psz_splitpath = _cdio_strsplit (psz_path, '/');
  p_stat = _fs_iso_stat_traverse (p_iso, p_root, p_psz_splitpath);
  free(p_root);
  _cdio_strfreev (p_psz_splitpath);

  return p_stat;
}

/*! 
  Read psz_path (a directory) and return a list of iso9660_stat_t
  of the files inside that. The caller must free the returned result.

  b_mode2 is historical. It is not used.
*/
CdioList_t * 
iso9660_fs_readdir (CdIo_t *p_cdio, const char psz_path[], bool b_mode2)
{
  iso9660_stat_t *p_stat;
  generic_img_private_t *p_env = (generic_img_private_t *) p_cdio->env;

  if (!p_cdio)   return NULL;
  if (!psz_path) return NULL;

  p_stat = iso9660_fs_stat (p_cdio, psz_path);
  if (!p_stat) return NULL;

  if (p_stat->type != _STAT_DIR) {
    free(p_stat->rr.psz_symlink);
    free(p_stat);
    return NULL;
  }

  {
    unsigned offset = 0;
    uint8_t *_dirbuf = NULL;
    CdioList_t *retval = _cdio_list_new ();

    if (p_stat->size != ISO_BLOCKSIZE * p_stat->secsize)
      {
	cdio_warn ("bad size for ISO9660 directory (%ud) should be (%lu)!",
		   (unsigned) p_stat->size, 
		   (unsigned long int) ISO_BLOCKSIZE * p_stat->secsize);
      }

    _dirbuf = calloc(1, p_stat->secsize * ISO_BLOCKSIZE);

    if (cdio_read_data_sectors (p_cdio, _dirbuf, p_stat->lsn, 
				ISO_BLOCKSIZE, p_stat->secsize))
	return NULL;

    while (offset < (p_stat->secsize * ISO_BLOCKSIZE))
      {
	iso9660_dir_t *p_iso9660_dir = (void *) &_dirbuf[offset];
	iso9660_stat_t *p_iso9660_stat;
	
	if (!iso9660_get_dir_len(p_iso9660_dir))
	  {
	    offset++;
	    continue;
	  }

	p_iso9660_stat = _iso9660_dir_to_statbuf(p_iso9660_dir, dunno,
						 p_env->i_joliet_level);
	_cdio_list_append (retval, p_iso9660_stat);

	offset += iso9660_get_dir_len(p_iso9660_dir);
      }

    cdio_assert (offset == (p_stat->secsize * ISO_BLOCKSIZE));

    free (_dirbuf);
    free (p_stat);
    return retval;
  }
}

/*! 
  Read psz_path (a directory) and return a list of iso9660_stat_t
  of the files inside that. The caller must free the returned result.
*/
CdioList_t * 
iso9660_ifs_readdir (iso9660_t *p_iso, const char psz_path[])
{
  iso9660_stat_t *p_stat;

  if (!p_iso)    return NULL;
  if (!psz_path) return NULL;

  p_stat = iso9660_ifs_stat (p_iso, psz_path);
  if (!p_stat)   return NULL;

  if (p_stat->type != _STAT_DIR) {
    free(p_stat->rr.psz_symlink);
    free(p_stat);
    return NULL;
  }

  {
    long int ret;
    unsigned offset = 0;
    uint8_t *_dirbuf = NULL;
    CdioList_t *retval = _cdio_list_new ();

    if (p_stat->size != ISO_BLOCKSIZE * p_stat->secsize)
      {
	cdio_warn ("bad size for ISO9660 directory (%ud) should be (%lu)!",
		   (unsigned int) p_stat->size, 
		   (unsigned long int) ISO_BLOCKSIZE * p_stat->secsize);
      }

    _dirbuf = calloc(1, p_stat->secsize * ISO_BLOCKSIZE);

    ret = iso9660_iso_seek_read (p_iso, _dirbuf, p_stat->lsn, p_stat->secsize);
    if (ret != ISO_BLOCKSIZE*p_stat->secsize) return NULL;
    
    while (offset < (p_stat->secsize * ISO_BLOCKSIZE))
      {
	iso9660_dir_t *p_iso9660_dir = (void *) &_dirbuf[offset];
	iso9660_stat_t *p_iso9660_stat;
	
	if (!iso9660_get_dir_len(p_iso9660_dir))
	  {
	    offset++;
	    continue;
	  }

	p_iso9660_stat = _iso9660_dir_to_statbuf(p_iso9660_dir, p_iso->b_xa,
						 p_iso->i_joliet_level);

	if (p_iso9660_stat) 
	  _cdio_list_append (retval, p_iso9660_stat);

	offset += iso9660_get_dir_len(p_iso9660_dir);
      }

    free (_dirbuf);

    if (offset != (p_stat->secsize * ISO_BLOCKSIZE)) {
      free (p_stat);
      _cdio_list_free (retval, true);
      return NULL;
    }

    free (p_stat);
    return retval;
  }
}

static iso9660_stat_t *
find_fs_lsn_recurse (CdIo_t *p_cdio, const char psz_path[], lsn_t lsn)
{
  CdioList_t *entlist = iso9660_fs_readdir (p_cdio, psz_path, true);
  CdioList_t *dirlist =  _cdio_list_new ();
  CdioListNode_t *entnode;
    
  cdio_assert (entlist != NULL);

  /* iterate over each entry in the directory */
  
  _CDIO_LIST_FOREACH (entnode, entlist)
    {
      iso9660_stat_t *statbuf = _cdio_list_node_data (entnode);
      char _fullname[4096] = { 0, };
      char *filename = (char *) statbuf->filename;

      snprintf (_fullname, sizeof (_fullname), "%s%s/", psz_path, filename);

      if (statbuf->type == _STAT_DIR
          && strcmp ((char *) statbuf->filename, ".") 
          && strcmp ((char *) statbuf->filename, ".."))
        _cdio_list_append (dirlist, strdup (_fullname));

      if (statbuf->lsn == lsn) {
	unsigned int len=sizeof(iso9660_stat_t)+strlen(statbuf->filename)+1;
	iso9660_stat_t *ret_stat = calloc(1, len);
	memcpy(ret_stat, statbuf, len);
        _cdio_list_free (entlist, true);
        _cdio_list_free (dirlist, true);
        return ret_stat;
      }
      
    }

  _cdio_list_free (entlist, true);

  /* now recurse/descend over directories encountered */

  _CDIO_LIST_FOREACH (entnode, dirlist)
    {
      char *_fullname = _cdio_list_node_data (entnode);
      iso9660_stat_t *ret_stat = find_fs_lsn_recurse (p_cdio, _fullname, lsn);

      if (NULL != ret_stat) {
        _cdio_list_free (dirlist, true);
        return ret_stat;
      }
    }

  _cdio_list_free (dirlist, true);
  return NULL;
}

static iso9660_stat_t *
find_ifs_lsn_recurse (iso9660_t *p_iso, const char psz_path[], lsn_t lsn)
{
  CdioList_t *entlist = iso9660_ifs_readdir (p_iso, psz_path);
  CdioList_t *dirlist =  _cdio_list_new ();
  CdioListNode_t *entnode;
    
  cdio_assert (entlist != NULL);

  /* iterate over each entry in the directory */
  
  _CDIO_LIST_FOREACH (entnode, entlist)
    {
      iso9660_stat_t *statbuf = _cdio_list_node_data (entnode);
      char _fullname[4096] = { 0, };
      char *filename = (char *) statbuf->filename;

      snprintf (_fullname, sizeof (_fullname), "%s%s/", psz_path, filename);

      if (statbuf->type == _STAT_DIR
          && strcmp ((char *) statbuf->filename, ".") 
          && strcmp ((char *) statbuf->filename, ".."))
        _cdio_list_append (dirlist, strdup (_fullname));

      if (statbuf->lsn == lsn) {
	unsigned int len=sizeof(iso9660_stat_t)+strlen(statbuf->filename)+1;
	iso9660_stat_t *ret_stat = calloc(1, len);
	memcpy(ret_stat, statbuf, len);
        _cdio_list_free (entlist, true);
        _cdio_list_free (dirlist, true);
        return ret_stat;
      }
      
    }

  _cdio_list_free (entlist, true);

  /* now recurse/descend over directories encountered */

  _CDIO_LIST_FOREACH (entnode, dirlist)
    {
      char *_fullname = _cdio_list_node_data (entnode);
      iso9660_stat_t *ret_stat = find_ifs_lsn_recurse (p_iso, _fullname, lsn);

      if (NULL != ret_stat) {
        _cdio_list_free (dirlist, true);
        return ret_stat;
      }
    }

  _cdio_list_free (dirlist, true);
  return NULL;
}

/*!
   Given a directory pointer, find the filesystem entry that contains
   lsn and return information about it.

   Returns stat_t of entry if we found lsn, or NULL otherwise.
 */
iso9660_stat_t *
iso9660_fs_find_lsn(CdIo_t *p_cdio, lsn_t i_lsn)
{
  return find_fs_lsn_recurse (p_cdio, "/", i_lsn);
}

/*!
   Given a directory pointer, find the filesystem entry that contains
   lsn and return information about it.

   Returns stat_t of entry if we found lsn, or NULL otherwise.
 */
iso9660_stat_t *
iso9660_ifs_find_lsn(iso9660_t *p_iso, lsn_t i_lsn)
{
  return find_ifs_lsn_recurse (p_iso, "/", i_lsn);
}

/*!
  Return true if ISO 9660 image has extended attrributes (XA).
*/
bool 
iso9660_ifs_is_xa (const iso9660_t * p_iso) 
{
  if (!p_iso) return false;
  return yep == p_iso->b_xa;
}


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