File: udf.c

package info (click to toggle)
udfclient 0.8.21-1
links: PTS, VCS
area: main
in suites: forky, sid
size: 1,140 kB
sloc: ansic: 16,639; sh: 3,050; makefile: 51
file content (6481 lines) | stat: -rw-r--r-- 211,396 bytes
/* $NetBSD$ */

/*
 * File "udf.c" is part of the UDFclient toolkit.
 * File $Id: udf.c,v 1.309 2024/10/14 14:09:19 reinoud Exp $ $Name:  $
 *
 * Copyright (c) 2003, 2004, 2005, 2006, 2011, 2020
 * 	Reinoud Zandijk <reinoud@netbsd.org>
 * All rights reserved.
 *
 * The UDFclient toolkit is distributed under the Clarified Artistic Licence.
 * A copy of the licence is included in the distribution as
 * `LICENCE.clearified.artistic' and a copy of the licence can also be
 * requested at the GNU foundantion's website.
 *
 * Visit the UDFclient toolkit homepage http://www.13thmonkey.org/udftoolkit/
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */



#include <stdio.h>
#include <fcntl.h>
#include <stdlib.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <assert.h>
#include <dirent.h>
#include <string.h>
#include <strings.h>
#include <limits.h>
#include <time.h>

#include "uscsilib.h"


/* for locals */
#include "udf.h"
#include "udf_bswap.h"
#include "udf_discop.h"
#include "udf_unix.h"
#include "uio.h"
#include "dirhash.h"
#include <pthread.h>


/* for scsilib */
const char *dvname="UDF device";


#ifndef MAX
#	define MAX(a,b) ((a)>(b)?(a):(b))
#	define MIN(a,b) ((a)<(b)?(a):(b))
#endif


/* #define DEBUG(a) { a; } */
#define DEBUG(a) if (0) { a; } 


/* global settings */
int     udf_verbose = UDF_VERBLEV_ACTIONS;

/* static structures shared over all programs */
struct discslist       udf_discs_list;
struct volumeset_list  udf_volumeset_list;
struct mountables_list udf_mountables;

#define UDF_INODE_NUM_GUESS  2048


/* predefines */
int  udf_validate_tag_and_crc_sums(union dscrptr *dscr);
void udf_node_mark_dirty(struct udf_node *udf_node);

static void udf_set_imp_id(struct regid *regid);
static void udf_set_app_id(struct regid *regid);
static void udf_node_unmark_dirty(struct udf_node *udf_node);
static void udf_init_desc_tag(struct desc_tag *tag, uint16_t id, uint16_t dscr_ver, uint16_t serial_num);
static int  udf_translate_icb_filetype_to_dirent_filetype(int udf_filetype);
static int  udf_remove_directory_prim(struct udf_node *dir_node, struct udf_node *udf_node, char *componentname);
static int  udf_remove_directory_entry(struct udf_node *dir_node, struct udf_node *udf_node, char *componentname);


/* external dumpers */
extern void udf_dump_descriptor(union dscrptr *dscrpt);
extern void udf_dump_file_entry(struct file_entry *fe);
extern void udf_dump_extfile_entry(struct extfile_entry *efe);
extern void udf_dump_alloc_extent(struct alloc_ext_entry *ext, int addr_type);
extern void udf_dump_vat_table(struct udf_part_mapping *udf_part_mapping);
extern void udf_dump_disc_anchors(struct udf_discinfo *disc);
extern void udf_dump_alive_sets(void);
extern void udf_dump_root_dir(struct udf_mountpoint *mountpoint);
extern void udf_dump_timestamp(char *dscr, struct timestamp *t);


/******************************************************************************************
 *
 * Filename space conversion
 *
 ******************************************************************************************/

void udf_to_unix_name(char *result, char *id, int len, struct charspec *chsp) {
	uint16_t  raw_name[1024], unix_name[1024];
	uint16_t *inchp, ch;
	uint8_t	 *outchp;
	int       ucode_chars, nice_uchars;

	assert(sizeof(char) == sizeof(uint8_t));
	outchp = (uint8_t *) result;
	if ((chsp->type == 0) && (strcmp((char*) chsp->inf, "OSTA Compressed Unicode") == 0)) {
		*raw_name = *unix_name = 0;
		ucode_chars = udf_UncompressUnicode(len, (uint8_t *) id, raw_name);
		ucode_chars = UnicodeLength((unicode_t *) raw_name, ucode_chars);
		nice_uchars = UDFTransName(unix_name, raw_name, ucode_chars);
		for (inchp = unix_name; nice_uchars>0; inchp++, nice_uchars--) {
			ch = *inchp;
			/* sloppy unicode -> latin */
			*outchp++ = ch & 255;
			if (!ch) break;
		}
		*outchp++ = 0;
	} else {
		/* assume 8bit char length byte latin-1 */
		assert(*id == 8);
		strncpy(result, id+1, len);
	}
}


void unix_to_udf_name(char *result, char *name, uint8_t *result_len, struct charspec *chsp) {
	uint16_t  raw_name[1024];
	int       udf_chars, name_len;
	char     *inchp;
	uint16_t *outchp;

	/* convert latin-1 or whatever to unicode-16 */
	*raw_name = 0;
	name_len  = 0;
	inchp  = name;
	outchp = raw_name;
	while (*inchp) {
		*outchp++ = (uint16_t) (*inchp++);
		name_len++;
	}

	if ((chsp->type == 0) && (strcmp((char *) chsp->inf, "OSTA Compressed Unicode") == 0)) {
		udf_chars = udf_CompressUnicode(name_len, 8, (unicode_t *) raw_name, (byte *) result);
	} else {
		/* assume 8bit char length byte latin-1 */
		*result++ = 8; udf_chars = 1;
		strcpy(result, name + 1);
		udf_chars += strlen(name);
	}
	*result_len = udf_chars;
}


static char *udf_get_compound_name(struct udf_mountpoint *mountpoint) {
	static char         compound[128+128+32+32+1];
	struct charspec    *charspec;
	struct udf_log_vol *udf_log_vol;
	struct udf_pri_vol *udf_pri_vol;
	char               *unix_name;

	udf_log_vol = mountpoint->udf_log_vol;
	udf_pri_vol = udf_log_vol->primary;

	charspec = &udf_pri_vol->pri_vol->desc_charset;
	assert(charspec->type == 0);
	assert(strcmp((const char *) charspec->inf, "OSTA Compressed Unicode")==0);

	unix_name = compound;

	udf_to_unix_name(unix_name, udf_pri_vol->pri_vol->volset_id, 128, charspec);
	strcat(unix_name, ":");
	unix_name += strlen(unix_name);

	udf_to_unix_name(unix_name, udf_pri_vol->pri_vol->vol_id, 32, charspec);
	strcat(unix_name, ":");
	unix_name += strlen(unix_name);

	udf_to_unix_name(unix_name, udf_log_vol->log_vol->logvol_id, 128, charspec);
	strcat(unix_name, ":");
	unix_name += strlen(unix_name);

	udf_to_unix_name(unix_name, mountpoint->fileset_desc->fileset_id, 32, charspec);

	return compound;
}


/******************************************************************************************
 *
 * Dump helpers for printing out information during parse
 *
 ******************************************************************************************/

void udf_dump_long_ad(char *prefix, struct long_ad *adr) {
	printf("%s at sector %d within partion space %d for %d bytes\n", prefix,
			udf_rw32(adr->loc.lb_num), udf_rw16(adr->loc.part_num),
			udf_rw32(adr->len)
			);
}


void udf_dump_id(char *prefix, int len, char *id, struct charspec *chsp) {
	uint16_t  raw_name[1024];
	uint16_t *pos, ch;
	int       ucode_chars;

	if (prefix) printf("%s ", prefix);
	if ((chsp->type == 0) && (strcmp((char *) chsp->inf, "OSTA Compressed Unicode") == 0)) {
		/* print the identifier using the OSTA compressed unicode */
		printf("`");
		ucode_chars = udf_UncompressUnicode(len, (uint8_t *) id, raw_name);
		for (pos = raw_name; ucode_chars > 0; pos++, ucode_chars--) {
			ch = *pos;		/* OSTA code decompresses to machine endian */
			if (!ch) break;
			if ((ch < 32) || (ch > 255)) {
				printf("[%d]", ch);
			} else {
				printf("%c", ch & 255);
			}
		}
		printf("`");
	} else {
		printf("(roughly) `%s`", id+1);
	}
	if (prefix) printf("\n");
}


void udf_dump_volume_name(char *prefix, struct udf_log_vol *udf_log_vol) {
	if (prefix) printf("%s%s", prefix, udf_log_vol->primary->udf_session->session_offset?" (local) ":" ");
	udf_dump_id(NULL, 128, udf_log_vol->primary->pri_vol->volset_id, &udf_log_vol->primary->pri_vol->desc_charset);
	printf(":");
	udf_dump_id(NULL,  32, udf_log_vol->primary->pri_vol->vol_id, &udf_log_vol->primary->pri_vol->desc_charset);
	printf(":");
	udf_dump_id(NULL, 128, udf_log_vol->log_vol->logvol_id, &udf_log_vol->log_vol->desc_charset);
	if (prefix) printf("\n");
}


/******************************************************************************************
 *
 * UDF tag checkers and size calculator
 *
 ******************************************************************************************/


/* not used extensively enough yet */
int udf_check_tag(union dscrptr *dscr) {
	struct desc_tag *tag = &dscr->tag;
	uint8_t *pos, sum, cnt;

	/* check TAG header checksum */
	pos = (uint8_t *) tag;
	sum = 0;

	for(cnt = 0; cnt < 16; cnt++) {
		if (cnt != 4) sum += *pos;
		pos++;
	}
	if (sum != tag->cksum) {
		/* bad tag header checksum; this is not a valid tag */
		DEBUG(printf("Bad checksum\n"));
		return EINVAL;
	}
	return 0;
}


int udf_check_tag_payload(union dscrptr *dscr) {
	struct desc_tag *tag = &dscr->tag;
	uint16_t crc;

	/* check payload CRC if applicable */
	if (udf_rw16(tag->desc_crc_len) == 0) return 0;

	crc = udf_cksum(((uint8_t *) tag) + UDF_DESC_TAG_LENGTH, udf_rw16(tag->desc_crc_len));
	if (crc != udf_rw16(tag->desc_crc)) {
		DEBUG(printf("ERROR: CRC bad read 0x%0x calc 0x%0x\n", udf_rw16(tag->desc_crc), crc));
		/* bad payload CRC; this is a broken tag */
		return EINVAL;
	}

	return 0;
}


int udf_validate_tag_sum(union dscrptr *dscr) {
	struct desc_tag *tag = &dscr->tag;
	uint8_t *pos, sum, cnt;

	/* calculate TAG header checksum */
	pos = (uint8_t *) tag;
	sum = 0;

	for(cnt = 0; cnt < 16; cnt++) {
		if (cnt != 4) sum += *pos;
		pos++;
	}
	tag->cksum = sum;	/* 8 bit */

	return 0;
}


/* assumes sector number of descriptor to be allready present */
int udf_validate_tag_and_crc_sums(union dscrptr *dscr) {
	struct desc_tag *tag = &dscr->tag;
	uint16_t crc;

	/* check payload CRC if applicable */
	if (udf_rw16(tag->desc_crc_len) > 0) {
		crc = udf_cksum(((uint8_t *) tag) + UDF_DESC_TAG_LENGTH, udf_rw16(tag->desc_crc_len));
		tag->desc_crc = udf_rw16(crc);
	}

	/* calculate TAG header checksum */
	return udf_validate_tag_sum(dscr);
}


int udf_check_tag_presence(union dscrptr *dscr, int TAG) {
	struct desc_tag *tag = &dscr->tag;
	int error;

	error = udf_check_tag(dscr);
	if (error) return error;

	if (udf_rw16(tag->id) != TAG) {
		DEBUG(fprintf(stderr, "looking for tag %d but found %d\n", TAG, udf_rw16(tag->id)));
		return ENOENT;
	}

	return 0;
}



/*
 * for malloc() purposes ... rather have an upperlimit than an exact size
 */
uint64_t udf_calc_tag_malloc_size(union dscrptr *dscr, uint32_t udf_sector_size) {
	uint32_t size, tag_id;

	tag_id = udf_rw16(dscr->tag.id);

	switch (tag_id) {
		case TAGID_LOGVOL :
			size  = sizeof(struct logvol_desc) - 1;					/* maps[1]		*/
			size += udf_rw32(dscr->lvd.mt_l);
			break;
		case TAGID_UNALLOC_SPACE :
			size  = sizeof(struct unalloc_sp_desc) - sizeof(struct extent_ad);	/* alloc_desc[1]	*/
			size += udf_rw32(dscr->usd.alloc_desc_num) * sizeof(struct extent_ad);
			break;
		case TAGID_FID :
			size = UDF_FID_SIZE + dscr->fid.l_fi + udf_rw16(dscr->fid.l_iu);
			size = (size + 3) & ~3;
			return size;		/* RETURN !! */
		case TAGID_LOGVOL_INTEGRITY :
			size  = sizeof(struct logvol_int_desc) - sizeof(uint32_t);		/* tables[1]		*/
			size += udf_rw32(dscr->lvid.l_iu);
			size += (2 * udf_rw32(dscr->lvid.num_part) * sizeof(uint32_t));
			break;
		case TAGID_SPACE_BITMAP :
			size  = sizeof(struct space_bitmap_desc) - 1;				/* data[1]		*/
			size += udf_rw32(dscr->sbd.num_bytes);
			break;
		case TAGID_SPARING_TABLE :
			size  = sizeof(struct udf_sparing_table) - sizeof(struct spare_map_entry);	/* entries[1]	*/
			size += udf_rw16(dscr->spt.rt_l) * sizeof(struct spare_map_entry);
			break;
		case TAGID_FENTRY :
			size  = sizeof(struct file_entry);
			size += udf_rw32(dscr->fe.l_ea) + udf_rw32(dscr->fe.l_ad)-1;		/* data[0] 		*/
			break;
		case TAGID_EXTFENTRY :
			size  = sizeof(struct extfile_entry);
			size += udf_rw32(dscr->efe.l_ea) + udf_rw32(dscr->efe.l_ad)-1;		/* data[0]		*/
			break;
		case TAGID_FSD :
			size  = sizeof(struct fileset_desc);
			break;
		default :
			size = sizeof(union dscrptr);
			break;
	}

	if ((size == 0) || (udf_sector_size == 0)) return 0;
	return ((size + udf_sector_size -1) / udf_sector_size) * udf_sector_size;
}


/* explicit only for FID's */
static int
udf_fidsize(struct fileid_desc *fid)
{
	int size;

	size = UDF_FID_SIZE + fid->l_fi + udf_rw16(fid->l_iu);
	size = (size + 3) & ~3;

	return size;
}


/******************************************************************************************
 *
 * Logical to physical adres transformation
 *
 ******************************************************************************************/


/* convert (udf_log_vol, vpart_num) to a udf_partion structure */
int udf_logvol_vpart_to_partition(struct udf_log_vol *udf_log_vol, uint32_t vpart_num, struct udf_part_mapping **udf_part_mapping_ptr, struct udf_partition **udf_partition_ptr) {
	struct udf_volumeset	 *udf_volumeset;
	struct udf_partition	 *udf_partition;
	struct udf_part_mapping  *udf_part_mapping;
	uint32_t		  part_num;
	int found;

	assert(udf_log_vol);
	assert(!SLIST_EMPTY(&udf_log_vol->part_mappings));

	/* clear result */
	if (udf_part_mapping_ptr) *udf_part_mapping_ptr = NULL;
	if (udf_partition_ptr)    *udf_partition_ptr    = NULL;

	/* map the requested partition map to the physical udf partition */
	found = 0;
	SLIST_FOREACH(udf_part_mapping, &udf_log_vol->part_mappings, next_mapping) {
		if (udf_part_mapping->udf_virt_part_num == vpart_num) {
			found = 1;
			break;
		}
	}
	if (!found) {
		printf("\t\t\tVirtual partition number %d not found!\n", vpart_num);
		return EINVAL;
	}

	assert(udf_part_mapping);	/* call me paranoid */
	part_num = udf_part_mapping->udf_phys_part_num;

	/* search for the physical partition information */
	udf_volumeset = udf_log_vol->primary->volumeset;
	SLIST_FOREACH(udf_partition, &udf_volumeset->parts, next_partition) {
		if (udf_rw16(udf_partition->partition->part_num) == part_num) break;
	}

	if (!udf_partition) {
		printf("\t\t\tNo information known about partition %d yet!\n", part_num);
		printf("\t\t\t\tPlease insert volume %d of this volumeset and try again\n", udf_part_mapping->vol_seq_num);
		return ENOENT;
	}

	if (udf_part_mapping_ptr) *udf_part_mapping_ptr = udf_part_mapping;
	if (udf_partition_ptr)    *udf_partition_ptr    = udf_partition;
	return 0;
}


/* no recursive translations yet (UDF OK) */
/* All translation is done in 64 bits to prevent bitrot and returns the PARTITION relative address */
int udf_vpartoff_to_sessionoff(struct udf_log_vol *udf_log_vol, struct udf_part_mapping *udf_part_mapping, struct udf_partition *udf_partition, uint64_t offset, uint64_t *ses_off, uint64_t *trans_valid_len) {
	struct spare_map_entry	 *sp_entry;
	struct udf_node		 *udf_node;
	struct udf_allocentry	 *alloc_entry;

	uint64_t	part_start, part_length;
	uint64_t	eff_sector, eff_offset;
	uint64_t	trans_sector;
	uint64_t	cur_offset;
	uint32_t	len, lb_num, block_offset;
	uint32_t	entry, entries;
	uint32_t	sector_size, lb_size;

	uint64_t	packet_num, packet_rlb;
	uint64_t	packet_len;

	uint32_t	vat_entries, *vat_pos;
	int		flags;

	assert(udf_part_mapping);
	assert(udf_partition);
	assert(ses_off);
	assert(trans_valid_len);

	/* not ok, but rather this than a dangling random value */
	*ses_off         = UINT_MAX;
	*trans_valid_len = 0;

	lb_size     = udf_log_vol->lb_size;
	sector_size = udf_log_vol->sector_size;
	part_start  = (uint64_t) udf_rw32(udf_partition->partition->start_loc) * sector_size;
	part_length = (uint64_t) udf_rw32(udf_partition->partition->part_len)  * sector_size;

	/* get the offset (in bytes) in the partition and check its validity */
	if (offset >= part_length) {
		printf("\t\toffset %"PRIu64" is outside partition %d!\n", offset, udf_rw16(udf_partition->partition->part_num));
		return EFAULT;
	}

	/* do the address translations based on the partition mapping type */
	/* translation of virt/sparable etc. is assumed to be done in logical block sizes */
	switch (udf_part_mapping->udf_part_mapping_type) {
		case UDF_PART_MAPPING_PHYSICAL :
			/* nothing to be done; physical is logical */
			*ses_off	 = part_start  + offset;				/* 1:1 */
			*trans_valid_len = part_length - offset;				/* rest of partition */
			return 0;

		case UDF_PART_MAPPING_VIRTUAL :
			vat_entries = udf_part_mapping->vat_entries;
			vat_pos = (uint32_t *) udf_part_mapping->vat_translation;

			/* this translation is dependent on logical sector numbers */
			eff_sector = offset / lb_size;
			eff_offset = offset % lb_size;

			/* TODO check range for logical sector against VAT length */
			assert(eff_sector < vat_entries);
			trans_sector     = vat_pos[eff_sector];
			*ses_off         = part_start + (trans_sector * lb_size) + eff_offset;	/* trans sectors are in lb->lb ? */
			*trans_valid_len = lb_size - eff_offset;				/* maximum one logical sector */
			return 0;

		case UDF_PART_MAPPING_SPARABLE :
			/* this translation is dependent on logical sector numbers */
			*ses_off   = part_start + offset;					/* 1:1 */
			eff_sector = offset / lb_size;
			eff_offset = offset % lb_size;

			/* transform on packet-length base */
			packet_len = udf_rw16(udf_part_mapping->udf_pmap->pms.packet_len);	/* in lb */
			entries    = udf_rw16(udf_part_mapping->sparing_table->rt_l);

			packet_num = (eff_sector / packet_len) * packet_len;
			packet_rlb =  eff_sector % packet_len;					/* within packet */

			/* translate this packet; source is in partition, destination is absolute disc address */
			sp_entry = &udf_part_mapping->sparing_table->entries[0];
			for (entry = 0; entry < entries; entry++) {
				if (udf_rw32(sp_entry->org) - packet_num == 0) {
					/* mappings contain absolute disc addresses, so no partition offsets please */
					*ses_off = (uint64_t) (udf_rw32(sp_entry->map) + packet_rlb) * lb_size + eff_offset;
					break;
				}
				sp_entry++;
			}
			*trans_valid_len = (packet_len - packet_rlb) * lb_size;			/* maximum one packet */
			return 0;

		case UDF_PART_MAPPING_META :
			/* We follow the allocation entries to calculate our offset */
			udf_node = udf_part_mapping->meta_file;
			assert(udf_node->addr_type != UDF_ICB_INTERN_ALLOC);
			
			/* find sector in the allocation space */
			UDF_MUTEX_LOCK(&udf_node->alloc_mutex);
			cur_offset = 0;
			TAILQ_FOREACH(alloc_entry, &udf_node->alloc_entries, next_alloc) {
				len       = alloc_entry->len;
				lb_num    = alloc_entry->lb_num;
				/* vpart_num = alloc_entry->vpart_num; */
				flags     = alloc_entry->flags;

				/* check overlap with this alloc entry */
				if (cur_offset + len > offset) {
					assert(((offset - cur_offset) % lb_size) == 0);	/* ought to be on sector boundary */
					if (flags != UDF_EXT_ALLOCATED)
						break;
					block_offset = offset - cur_offset;
					*ses_off     = part_start + lb_num * lb_size + block_offset;	/* 1:1 within the block */
					*trans_valid_len = len - block_offset;				/* rest of this chunk   */
					UDF_MUTEX_UNLOCK(&udf_node->alloc_mutex);
					return 0;
				}
				cur_offset += len;
			} /* FOREACH */
			UDF_MUTEX_UNLOCK(&udf_node->alloc_mutex);

			printf("\t\toffset %"PRIu64" is not translated within current metadata partition %d file descriptor!\n", offset, udf_rw16(udf_partition->partition->part_num));
			return EFAULT;
		case UDF_PART_MAPPING_ERROR :
		default :
			break;
	}
	printf("Unsupported or bad mapping %d; can't translate\n", udf_part_mapping->udf_part_mapping_type);

	return EFAULT;
}



/******************************************************************************************
 *
 * udf_node creator, destructor and syncer
 *
 ******************************************************************************************/


static mode_t udf_perm_to_unix_mode(uint32_t perm) {
	mode_t mode;

	mode  = ((perm & UDF_FENTRY_PERM_USER_MASK)      );
	mode |= ((perm & UDF_FENTRY_PERM_GRP_MASK  ) >> 2);
	mode |= ((perm & UDF_FENTRY_PERM_OWNER_MASK) >> 4);

	return mode;
}


static uint32_t unix_mode_to_udf_perm(mode_t mode) {
	uint32_t perm;
	
	perm  = ((mode & S_IRWXO)     );
	perm |= ((mode & S_IRWXG) << 2);
	perm |= ((mode & S_IRWXU) << 4);
	perm |= ((mode & S_IWOTH) << 3);
	perm |= ((mode & S_IWGRP) << 5);
	perm |= ((mode & S_IWUSR) << 7);

	return perm;
}


/*
 * Fill in timestamp structure based on clock_gettime(). Time is reported back as a time_t
 * accompanied with a nano second field.
 *
 * The husec, usec and csec could be relaxed in type.
 */
static void udf_timespec_to_timestamp(struct timespec *timespec, struct timestamp *timestamp) {
	struct tm tm;
	uint64_t husec, usec, csec;

	bzero(timestamp, sizeof(struct timestamp));
	gmtime_r(&timespec->tv_sec, &tm);

	/*
	 * Time type and time zone : see ECMA 1/7.3, UDF 2., 2.1.4.1, 3.1.1.
	 *
	 * Lower 12 bits are two complement signed timezone offset if bit 12
	 * (method 1) is clear. Otherwise if bit 12 is set, specify timezone
	 * offset to -2047 i.e. unsigned `zero'
	 */

	timestamp->type_tz	= udf_rw16((1<<12) + 0);	/* has to be method 1 for CUT/GMT */
	timestamp->year		= udf_rw16(tm.tm_year + 1900);
	timestamp->month	= tm.tm_mon + 1;		/* `tm' structure uses 0..11 for months */
	timestamp->day		= tm.tm_mday;
	timestamp->hour		= tm.tm_hour;
	timestamp->minute	= tm.tm_min;
	timestamp->second	= tm.tm_sec;

	usec   = (timespec->tv_nsec + 500) / 1000;	/* round (if possible)        */
	husec  =   usec / 100;
	usec  -=  husec * 100;				/* we only want 0-99 in usec  */
	csec   =  husec / 100;				/* we       get 0-99 in csec  */
	husec -=   csec * 100;				/* we only want 0-99 in husec */

	timestamp->centisec	= csec;
	timestamp->hund_usec	= husec;
	timestamp->usec		= usec;
}


void udf_set_timestamp_now(struct timestamp *timestamp) {
	struct timespec now;

	clock_gettime(CLOCK_REALTIME, &now);
	udf_timespec_to_timestamp(&now, timestamp);
}


/* implemented as a seperate function to allow tuning */
void udf_set_timespec_now(struct timespec *timespec) {
	clock_gettime(CLOCK_REALTIME, timespec);
}


int udf_insanetimespec(struct timespec *check) {
	struct timespec now;
	struct tm tm;

	gmtime_r(&check->tv_sec, &tm);

	/* since our converters can only deal with timestamps after 1970 we
	 * reject earlier */
	if (tm.tm_year < 1970) return 1;

	/* don't accept values from the future; FFS or NFS might not mind, but
	 * UDF does! */
	clock_gettime(CLOCK_REALTIME, &now);
	if (now.tv_sec < check->tv_sec)
		return 1;
	if ((now.tv_sec == check->tv_sec) && (now.tv_nsec < check->tv_nsec))
		return 1;

	return 0;
}


/*       
 * Timestamp to timespec conversion code is taken with small modifications
 * from FreeBSD /sys/fs/udf by Scott Long <scottl@freebsd.org>
 */

static int mon_lens[2][12] = {
	{31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31},
	{31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}
};


static int
udf_isaleapyear(int year)
{       
	int i;
	
	i = (year % 4) ? 0 : 1;
	i &= (year % 100) ? 1 : 0;
	i |= (year % 400) ? 0 : 1;
	
	return i;
}


static void udf_timestamp_to_timespec(struct timestamp *timestamp, struct timespec *timespec) {
	uint32_t usecs, secs, nsecs;
	uint16_t tz;
	int i, lpyear, daysinyear, year;

	timespec->tv_sec  = secs  = 0;
	timespec->tv_nsec = nsecs = 0;

       /*
	* DirectCD seems to like using bogus year values.
	* Distrust time->month especially, since it will be used for an array
	* index.
	*/
	year = udf_rw16(timestamp->year);
	if ((year < 1970) || (timestamp->month > 12)) {
		return;
	}
	
	/* Calculate the time and day */
	usecs = timestamp->usec + 100*timestamp->hund_usec + 10000*timestamp->centisec;
	nsecs = usecs * 1000;
	secs  = timestamp->second; 
	secs += timestamp->minute * 60;
	secs += timestamp->hour * 3600;
	secs += (timestamp->day-1) * 3600 * 24;			/* day : 1-31 */
	
	/* Calclulate the month */
	lpyear = udf_isaleapyear(year);
	for (i = 1; i < timestamp->month; i++)
		secs += mon_lens[lpyear][i-1] * 3600 * 24;	/* month: 1-12 */
 
	for (i = 1970; i < year; i++) { 
		daysinyear = udf_isaleapyear(i) + 365 ;
		secs += daysinyear * 3600 * 24;
	}

	/*
	 * Calculate the time zone.  The timezone is 12 bit signed 2's
	 * compliment, so we gotta do some extra magic to handle it right.
	 */
	tz  = udf_rw16(timestamp->type_tz);
	tz &= 0x0fff;				/* only lower 12 bits are significant */
	if (tz & 0x0800)			/* sign extention */
		tz |= 0xf000;

	/* TODO check timezone conversion */
#if 1
	/* check if we are specified a timezone to convert */
	if (udf_rw16(timestamp->type_tz) & 0x1000)
		if ((int16_t) tz != -2047)
			secs -= (int16_t) tz * 60;
#endif
	timespec->tv_sec  = secs;
	timespec->tv_nsec = nsecs;
}


static void udf_node_get_fileinfo(struct udf_node *udf_node, union dscrptr *dscrptr) {
	struct stat          *stat;
	struct file_entry    *file_entry;
	struct extfile_entry *extfile_entry;
	struct timestamp     *atime, *mtime, *ctime, *attrtime;
	uint64_t inf_len, unique_id;
	uint32_t uid, gid, udf_perm;
	uint16_t fe_tag;
	uint16_t udf_icbtag_flags, serial_num, link_cnt;
	uint8_t  filetype;

	assert(udf_node);
	assert(dscrptr);
	stat   = &udf_node->stat;

	/* check if its an normal file entry or a extended file entry ICB */
	fe_tag = udf_rw16(dscrptr->tag.id);
	if (fe_tag == TAGID_FENTRY) {
		file_entry = &dscrptr->fe;
#if 0
		prev_direct_entries = udf_rw32(file_entry->icbtag.prev_num_dirs);
		strat_param16  = udf_rw16(* (uint16_t *) (file_entry->icbtag.strat_param));
		entries        = udf_rw16(file_entry->icbtag.max_num_entries);
		strategy       = udf_rw16(file_entry->icbtag.strat_type);
		data_length    = udf_rw32(file_entry->l_ad);
		addr_type      = udf_rw16(file_entry->icbtag.flags) & UDF_ICB_TAG_FLAGS_ALLOC_MASK;
		pos            = &file_entry->data[0] + udf_rw32(file_entry->l_ea);
#endif
		filetype         = file_entry->icbtag.file_type;
		inf_len          = udf_rw64(file_entry->inf_len);
		uid              = udf_rw32(file_entry->uid);
		gid              = udf_rw32(file_entry->gid);
		udf_perm         = udf_rw32(file_entry->perm);
		serial_num       = udf_rw16(file_entry->tag.serial_num);
		udf_icbtag_flags = udf_rw16(file_entry->icbtag.flags);
		link_cnt         = udf_rw16(file_entry->link_cnt);
		unique_id        = udf_rw64(file_entry->unique_id);
		atime            = &file_entry->atime;
		mtime            = &file_entry->mtime;
		ctime		 = &file_entry->mtime;		/* XXX assumption */
		attrtime         = &file_entry->attrtime;
	} else if (fe_tag == TAGID_EXTFENTRY) {
		extfile_entry = &dscrptr->efe;
#if 0
		prev_direct_entries = udf_rw32(extfile_entry->icbtag.prev_num_dirs);
		strat_param16  = udf_rw16(* (uint16_t *) (extfile_entry->icbtag.strat_param));
		entries        = udf_rw16(extfile_entry->icbtag.max_num_entries);
		strategy       = udf_rw16(extfile_entry->icbtag.strat_type);
		data_length    = udf_rw32(extfile_entry->l_ad);
		addr_type      = udf_rw16(extfile_entry->icbtag.flags) & UDF_ICB_TAG_FLAGS_ALLOC_MASK;
		pos            = &extfile_entry->data[0] + udf_rw32(extfile_entry->l_ea);
#endif
		filetype         = extfile_entry->icbtag.file_type;
		inf_len          = udf_rw64(extfile_entry->inf_len);
		uid              = udf_rw32(extfile_entry->uid);
		gid              = udf_rw32(extfile_entry->gid);
		udf_perm         = udf_rw32(extfile_entry->perm);
		serial_num       = udf_rw16(extfile_entry->tag.serial_num);
		udf_icbtag_flags = udf_rw16(extfile_entry->icbtag.flags);
		link_cnt         = udf_rw16(extfile_entry->link_cnt);	/* how many FID's are linked to this (ext)fentry	*/
		unique_id        = udf_rw64(extfile_entry->unique_id);	/* unique file ID					*/
		atime            = &extfile_entry->atime;
		mtime            = &extfile_entry->mtime;
		ctime		 = &extfile_entry->ctime;
		attrtime         = &extfile_entry->attrtime;
	} else {
		printf("udf_node_set_file_info : help! i can't be here!!! i got a %d tag\n", fe_tag);
		udf_dump_descriptor(dscrptr);
		return;
	}

	/* fill in (parts of) the stat structure */
	/* XXX important info missing still like access mode, times etc. XXX */
	udf_node->udf_filetype     = filetype;
	udf_node->serial_num       = serial_num;
	udf_node->udf_icbtag_flags = udf_icbtag_flags;
	udf_node->link_cnt         = link_cnt;		/* how many FID's are linked to this (ext)fentry	*/
	udf_node->unique_id        = unique_id;		/* unique file ID					*/

	/* fill in stat basics */
	bzero(stat, sizeof(struct stat));
	stat->st_ino     = unique_id;				/* lowest 32 bit(!) only */
	stat->st_mode    = udf_perm_to_unix_mode(udf_perm);	/* CONVERT from udf_perm */
	stat->st_mode   |= (udf_translate_icb_filetype_to_dirent_filetype(filetype) & DT_DIR) ? S_IFDIR : S_IFREG;
	stat->st_uid     = uid;
	stat->st_gid     = gid;

	/* ... times */
	udf_timestamp_to_timespec(atime,    &stat->st_atimespec);
	udf_timestamp_to_timespec(mtime,    &stat->st_mtimespec);
	udf_timestamp_to_timespec(attrtime, &stat->st_ctimespec);
#ifndef NO_STAT_BIRTHTIME
	udf_timestamp_to_timespec(ctime,    &stat->st_birthtimespec);
#endif

	/* ... sizes */
	stat->st_size    = inf_len;
	stat->st_blksize = udf_node->udf_log_vol->lb_size;

	/* special: updatables */
	stat->st_nlink   = link_cnt;
	stat->st_blocks  = (stat->st_size + 512 -1)/512;	/* blocks are hardcoded 512 bytes/sector in stat :-/ */
	return;
}


static void udf_node_set_fileinfo(struct udf_node *udf_node, union dscrptr *dscrptr) {
	struct stat          *stat;
	struct file_entry    *file_entry;
	struct extfile_entry *extfile_entry;
	struct timestamp     *atime, *mtime, *ctime, *attrtime;
	uint64_t inf_len, unique_id;
	uint32_t uid, gid, udf_perm;
	uint16_t fe_tag, serial_num, link_cnt;
	uint8_t  filetype;

	assert(udf_node);
	assert(dscrptr);
	stat   = &udf_node->stat;

	/* set (parts of) the stat structure */
	/* XXX important info missing still like times etc. XXX */
	uid      = stat->st_uid;
	gid      = stat->st_gid;
	inf_len  = stat->st_size;
	udf_perm = unix_mode_to_udf_perm(stat->st_mode);	/* conversion to UDF perm. */

	filetype   = udf_node->udf_filetype;
	unique_id  = udf_node->unique_id;
	serial_num = udf_node->serial_num;
	link_cnt   = udf_node->link_cnt;

	/* check if its to be written in an normal file entry or a extended file entry ICB */
	fe_tag = udf_rw16(dscrptr->tag.id);
	if (fe_tag == TAGID_FENTRY) {
		file_entry = &dscrptr->fe;
#if 0
		prev_direct_entries = udf_rw32(file_entry->icbtag.prev_num_dirs);
		strat_param16  = udf_rw16(* (uint16_t *) (file_entry->icbtag.strat_param));
		entries        = udf_rw16(file_entry->icbtag.max_num_entries);
		strategy       = udf_rw16(file_entry->icbtag.strat_type);
		data_length    = udf_rw32(file_entry->l_ad);
		addr_type      = udf_rw16(file_entry->icbtag.flags) & UDF_ICB_TAG_FLAGS_ALLOC_MASK;
		pos            = &file_entry->data[0] + udf_rw32(file_entry->l_ea);
#endif
		file_entry->icbtag.file_type = filetype;
		file_entry->inf_len         = udf_rw64(inf_len);
		file_entry->uid             = udf_rw32(uid);
		file_entry->gid             = udf_rw32(gid);
		file_entry->perm            = udf_rw32(udf_perm);
		file_entry->tag.serial_num  = udf_rw16(serial_num);
		file_entry->link_cnt        = udf_rw16(link_cnt);
		file_entry->unique_id       = udf_rw64(unique_id);
		atime                       = &file_entry->atime;
		mtime                       = &file_entry->mtime;
		ctime                       = mtime;			/* XXX assumption */
		attrtime                    = &file_entry->attrtime;
	} else if (fe_tag == TAGID_EXTFENTRY) {
		extfile_entry = &dscrptr->efe;
#if 0
		prev_direct_entries = udf_rw32(extfile_entry->icbtag.prev_num_dirs);
		strat_param16  = udf_rw16(* (uint16_t *) (extfile_entry->icbtag.strat_param));
		entries        = udf_rw16(extfile_entry->icbtag.max_num_entries);
		strategy       = udf_rw16(extfile_entry->icbtag.strat_type);
		data_length    = udf_rw32(extfile_entry->l_ad);
		addr_type      = udf_rw16(extfile_entry->icbtag.flags) & UDF_ICB_TAG_FLAGS_ALLOC_MASK;
		pos            = &extfile_entry->data[0] + udf_rw32(extfile_entry->l_ea);
#endif
		extfile_entry->icbtag.file_type = filetype;
		extfile_entry->inf_len        = udf_rw64(inf_len);
		extfile_entry->uid            = udf_rw32(uid);
		extfile_entry->gid            = udf_rw32(gid);
		extfile_entry->perm           = udf_rw32(udf_perm);
		extfile_entry->tag.serial_num = udf_rw16(serial_num);
		extfile_entry->link_cnt       = udf_rw16(link_cnt);	/* how many FID's are linked to this (ext)fentry	*/
		extfile_entry->unique_id      = udf_rw64(unique_id);	/* unique file ID					*/
		atime          = &extfile_entry->atime;
		mtime          = &extfile_entry->mtime;
		ctime          = &extfile_entry->ctime;
		attrtime       = &extfile_entry->attrtime;
	} else {
		printf("udf_node_set_file_info : help! i can't be here!!! i got a %d tag\n", fe_tag);
		udf_dump_descriptor(dscrptr);
		return;
	}
	/* FILL in {atime, mtime, attrtime} TIMES! */
	udf_timespec_to_timestamp(&stat->st_atimespec,     atime);
	udf_timespec_to_timestamp(&stat->st_mtimespec,     mtime);
	udf_timespec_to_timestamp(&stat->st_ctimespec,     attrtime);
#ifndef NO_STAT_BIRTHTIME
	udf_timespec_to_timestamp(&stat->st_birthtimespec, ctime);
#else
	memcpy(ctime, mtime, sizeof(*ctime));
#endif

	return;
}


/* with 32 bits ino_t, a maximum of about 8 TB discs are supported (1<<32) * 2KB*/
ino_t udf_calc_hash(struct long_ad *icbptr) {
	/* TODO unique file-id would be better */
	return (ino_t) udf_rw32(icbptr->loc.lb_num);
}


void udf_insert_node_in_hash(struct udf_node *udf_node) {
	struct udf_log_vol *log_vol;
	uint32_t     bucket;
	ino_t        hashkey;
	struct long_ad icb;

	icb.loc.lb_num = udf_rw32(TAILQ_FIRST(&udf_node->dscr_allocs)->lb_num);

	log_vol           = udf_node->udf_log_vol;
	hashkey           = udf_calc_hash(&icb);
	udf_node->hashkey = hashkey;
	bucket            = hashkey & UDF_INODE_HASHMASK;
	LIST_INSERT_HEAD(&log_vol->udf_nodes[bucket], udf_node, next_node);
}


/* dispose udf_node's administration */
void udf_dispose_udf_node(struct udf_node *udf_node) {
	struct udf_allocentry *alloc_entry;
	struct udf_buf	 *buf_entry;
	struct udf_node	 *lookup;
	uint32_t bucket;
	ino_t    hashkey;

	if (!udf_node) return;

/* XXX locks? XXX */
	UDF_MUTEX_LOCK(&udf_node->alloc_mutex);

	if (udf_node->dirty) {
		DEBUG(printf("Warning: disposing dirty node\n"));
		udf_node_unmark_dirty(udf_node);
	}

	/* free all associated buffers */
	UDF_MUTEX_LOCK(&udf_bufcache->bufcache_lock);
	UDF_MUTEX_LOCK(&udf_node->buf_mutex);
		/* due to this `trick' we don't need to use a marker */
		while ((buf_entry = TAILQ_FIRST(&udf_node->vn_bufs))) {
			udf_mark_buf_clean(udf_node, buf_entry);	/* its destroyed so not dirty */
			udf_mark_buf_allocated(udf_node, buf_entry);	/* i.e. taken care of */
			udf_detach_buf_from_node(udf_node, buf_entry);
			udf_free_buf_entry(buf_entry);
		}
		/* free in-node filedata blob if present */
		if (udf_node->intern_data)
			free(udf_node->intern_data);
	UDF_MUTEX_UNLOCK(&udf_node->buf_mutex);
	UDF_MUTEX_UNLOCK(&udf_bufcache->bufcache_lock);

	/* free our extended attribute administration if present */
	if (udf_node->extattrfile_icb)
		free(udf_node->extattrfile_icb);
	if (udf_node->streamdir_icb)
		free(udf_node->streamdir_icb);
	if (udf_node->extended_attr)
		free(udf_node->extended_attr);

	/* free dscr_allocs queue */
	while ((alloc_entry = TAILQ_FIRST(&udf_node->dscr_allocs))) {
		TAILQ_REMOVE(&udf_node->dscr_allocs, alloc_entry, next_alloc);
		free(alloc_entry);
	}

	/* free allocation queue */
	while ((alloc_entry = TAILQ_FIRST(&udf_node->alloc_entries))) {
		TAILQ_REMOVE(&udf_node->alloc_entries, alloc_entry, next_alloc);
		free(alloc_entry);
	}

	/* if its part of a logical volume, delete it in its hash table */
	if (udf_node->udf_log_vol) {
		hashkey = udf_node->hashkey;
		bucket  = hashkey & UDF_INODE_HASHMASK;
		LIST_FOREACH(lookup, &udf_node->udf_log_vol->udf_nodes[bucket], next_node) {
			/* hashkey doesn't matter; just remove same udf_node pointer */
			if (lookup == udf_node) {
				assert(lookup->hashkey == hashkey);
				DEBUG(printf("removal of udf_node from the hash table\n"));
				LIST_REMOVE(lookup, next_node);
				break;
			}
		}
	}
	UDF_MUTEX_UNLOCK(&udf_node->alloc_mutex);

	/* free the node */
	free(udf_node);
}


uint64_t udf_increment_unique_id(struct udf_log_vol *udf_log_vol) {
	uint64_t unique_id, next_unique_id;

	/* lock? */
	unique_id = udf_log_vol->next_unique_id;

	/* increment according to UDF 3/3.2.1.1 */
	next_unique_id = unique_id + 1;
	if (((next_unique_id << 32) >> 32) < 16) next_unique_id |= 16;

	udf_log_vol->next_unique_id = next_unique_id;
	DEBUG(printf("next unique_id <-- %"PRIu64"\n", udf_log_vol->next_unique_id));

	return unique_id;
}


int udf_init_udf_node(struct udf_mountpoint *mountpoint, struct udf_log_vol *udf_log_vol, char *what, struct udf_node **udf_nodeptr) {
	struct udf_node	*udf_node;
	uint32_t lb_size, data_space_avail;
	int descr_ver;

	what = what;	/* not used yet */

	assert(udf_log_vol);
	lb_size = udf_log_vol->lb_size;

	/* get ourselves some space */
	udf_node = calloc(1, sizeof(struct udf_node));
	if (!udf_node) return ENOMEM;

	/* setup basic udf_node */
	udf_node->addr_type = UDF_ICB_LONG_ALLOC;
	udf_node->icb_len   = sizeof(struct long_ad);

	udf_node->serial_num       = 1;
	udf_node->udf_icbtag_flags = UDF_ICB_INTERN_ALLOC;
	udf_node->link_cnt         = 1;						/* how many FID's are linked to this node */
	udf_node->unique_id        = 0;						/* unique file ID unknown		  */

	/* get internal space available for internal nodes */
	/* TODO keep in mind the extended attributes! XXX */
	descr_ver = udf_rw16(udf_log_vol->log_vol->tag.descriptor_ver);
	if (descr_ver == 2) {
		/* TODO reserve some space for the icb creation time */
		data_space_avail = lb_size - sizeof(struct file_entry)    - 0; /* udf_rw32(file_entry->l_ea) */
	} else {
		data_space_avail = lb_size - sizeof(struct extfile_entry) - 0; /* udf_rw32(extfile_entry->l_ea) */
	}
	udf_node->intern_free = data_space_avail;
	udf_node->intern_data = NULL;
	udf_node->intern_len  = 0;

	/* finalise udf_node */
	udf_node->mountpoint  = mountpoint;
	udf_node->udf_log_vol = udf_log_vol;
	TAILQ_INIT(&udf_node->dscr_allocs);
	TAILQ_INIT(&udf_node->alloc_entries);
	TAILQ_INIT(&udf_node->vn_bufs);
	UDF_MUTEX_INIT(&udf_node->alloc_mutex);
	UDF_MUTEX_INIT(&udf_node->buf_mutex);

	/* XXX udf_node_lock NOT USED XXX */
	/* pthread_rwlock_init(&udf_node->udf_node_lock, NULL); */

	*udf_nodeptr = udf_node;
	return 0;
}


int udf_allocate_udf_node_on_disc(struct udf_node *udf_node) {
	struct udf_allocentry *alloc_entry;
	uint32_t  lb_num, lb_size;
	uint16_t  vpart_num;
	int       error;

	assert(udf_node);
	assert(udf_node->udf_log_vol);
	assert(udf_node->udf_log_vol->log_vol);

	lb_size   = udf_node->udf_log_vol->lb_size;
	assert(lb_size);

	/* pre-allocate node; its needed in directory linkage for now */
	error = udf_allocate_lbs(udf_node->udf_log_vol, UDF_C_NODE, /*num lb */ 1, "New FID", &vpart_num, &lb_num, NULL);
	if (error) return error;

	alloc_entry = calloc(1, sizeof(struct udf_allocentry));
	if (!alloc_entry) {
		return ENOMEM;
	}

	alloc_entry->len        = lb_size;
	alloc_entry->vpart_num  = vpart_num;
	alloc_entry->lb_num     = lb_num;
	alloc_entry->flags      = 0;
	TAILQ_INSERT_TAIL(&udf_node->dscr_allocs, alloc_entry, next_alloc);

	assert(error == 0);
	return error;
}


/* note: the udf_node (inode) is not stored in a hashtable! hash value is still invalid */
/* TODO remember our extended attributes and remember our streamdir long_ad  */
int udf_readin_anon_udf_node(struct udf_log_vol *udf_log_vol, union dscrptr *given_dscrptr, struct long_ad *udf_icbptr, char *what, struct udf_node **udf_nodeptr) {
	union  dscrptr  	*dscrptr;
	struct udf_node 	*udf_node;
	struct udf_allocentry	*alloc_entry;
	struct udf_allocentry	*cur_alloc, *next_alloc;
	struct file_entry	*file_entry;
	struct extfile_entry	*extfile_entry;
	struct alloc_ext_entry	*alloc_ext_entry;
	struct long_ad		*l_ad;
	struct short_ad		*s_ad;
	uint64_t		 inf_len, calculated_len;
	uint32_t		 lb_size, entries;
	uint64_t		 data_length;
	uint32_t		 data_space_avail;
	uint32_t		 fe_tag;
	uint64_t		 len;
	uint32_t		 lb_num, vpart_num;
	uint32_t		 icb_len;
	int16_t			 addr_type;
	uint8_t			*pos;
	uint8_t			 flags;
	int			 error, advance_sector;

	if ((udf_icbptr->loc.lb_num == 0) && (udf_icbptr->loc.part_num == 0) && (udf_icbptr->len == 0)) return ENOENT;

	DEBUG(printf("udf_readin_anon_udf_node for %s\n", what));

	error = udf_init_udf_node(/*mountpoint*/ NULL, udf_log_vol, what, &udf_node);
	DEBUG(
		if (error) printf("While reading in `anononymous' udf_node : got error %s\n", strerror(error));
	);
	if (error) return error;

	*udf_nodeptr = udf_node;

	assert(udf_log_vol);
	lb_size     = udf_log_vol->lb_size;

	/* read in descriptor if not provided to us */
	dscrptr   = NULL;
	len       = lb_size;					/* nodes are defined in lb_size only (?) */
	lb_num    = udf_rw32(udf_icbptr->loc.lb_num);
	vpart_num = udf_rw16(udf_icbptr->loc.part_num);
	if (!given_dscrptr) {
		error = udf_read_logvol_descriptor(udf_log_vol, vpart_num, lb_num, what, &dscrptr, NULL);
		if (error) {
			*udf_nodeptr = NULL;
			return error;
		}
	} else {
		dscrptr = given_dscrptr;
	}

	fe_tag = udf_rw16(dscrptr->tag.id);
	if (fe_tag != TAGID_FENTRY && fe_tag != TAGID_EXTFENTRY) {
		/* something wrong with this address; it doesn't start with a file entry */
		printf("UDF: bad udf_node for %s; got a %d tag\n", what, fe_tag);
		if (dscrptr != given_dscrptr) free(dscrptr);
		udf_dispose_udf_node(udf_node);
		*udf_nodeptr = NULL;
		return EFAULT;
	}

	/* get as much info as possible */
	udf_node_get_fileinfo(udf_node, dscrptr);

	/* reset pending write count */
	udf_node->v_numoutput = 0;

	/* initialise various variables for extracting allocation information */
	inf_len = 0; data_length = 0; lb_num = 0; len = 0; vpart_num = 0; pos = NULL;
	data_space_avail = 0;

	next_alloc = calloc(1, sizeof(struct udf_allocentry));
	if (!next_alloc) {
		if (dscrptr != given_dscrptr) free(dscrptr);
		udf_dispose_udf_node(udf_node);
		*udf_nodeptr = NULL;
		return ENOMEM;
	}
	next_alloc->len       = lb_size;
	next_alloc->lb_num    = udf_rw32(udf_icbptr->loc.lb_num);
	next_alloc->vpart_num = udf_rw16(udf_icbptr->loc.part_num);

	entries = 1;
	calculated_len = 0;

	error = 0;
	addr_type = -1;
	do {
		cur_alloc = next_alloc;
		next_alloc = calloc(1, sizeof(struct udf_allocentry));
		if (!next_alloc) {
			if (dscrptr != given_dscrptr) free(dscrptr);
			udf_dispose_udf_node(udf_node);
			*udf_nodeptr = NULL;
			return ENOMEM;
		}
		memcpy(next_alloc, cur_alloc, sizeof(struct udf_allocentry));
		TAILQ_INSERT_TAIL(&udf_node->dscr_allocs, cur_alloc, next_alloc);

		/* process this allocation descriptor */
		/* note that we don't store the file descriptors -> XXX impl. use stuff gets lost here */
		fe_tag = udf_rw16(dscrptr->tag.id);
		switch (fe_tag) {
			case TAGID_FENTRY :
				/* allocation descriptors follow this tag */
				file_entry       = &dscrptr->fe;
				entries          = udf_rw16(file_entry->icbtag.max_num_entries);
				data_length      = udf_rw32(file_entry->l_ad);
				pos              = &file_entry->data[0] + udf_rw32(file_entry->l_ea);
				inf_len          = udf_rw64(file_entry->inf_len);
				addr_type        = udf_rw16(file_entry->icbtag.flags) & UDF_ICB_TAG_FLAGS_ALLOC_MASK;
				data_space_avail = lb_size - sizeof(struct file_entry) - udf_rw32(file_entry->l_ea);
				/* process extended attributes */
				/* keep a trace of the descriptors in this udf_node */
				UDF_VERBOSE_MAX(udf_dump_file_entry(file_entry));
				break;
			case TAGID_EXTFENTRY :
				/* allocation descriptors follow this tag */
				extfile_entry    = &dscrptr->efe;
				entries          = udf_rw16(extfile_entry->icbtag.max_num_entries);
				data_length      = udf_rw32(extfile_entry->l_ad);
				pos              = &extfile_entry->data[0] + udf_rw32(extfile_entry->l_ea);
				inf_len          = udf_rw64(extfile_entry->inf_len);
				addr_type        = udf_rw16(extfile_entry->icbtag.flags) & UDF_ICB_TAG_FLAGS_ALLOC_MASK;
				data_space_avail = lb_size - sizeof(struct extfile_entry) - udf_rw32(extfile_entry->l_ea);
				/* process extended attributes */
				/* keep a trace of the descriptors in this udf_node */
				UDF_VERBOSE_MAX(udf_dump_extfile_entry(extfile_entry));
				break;
			case TAGID_ALLOCEXTENT :
				/* allocation descriptors follow this tag; treat as if continuation of a (ext)file entry*/
				alloc_ext_entry  = &dscrptr->aee;
				data_length      = udf_rw32(alloc_ext_entry->l_ad);
				pos		 = &alloc_ext_entry->data[0];
				assert(addr_type >= 0);

				/* keep a trace of the descriptors in this udf_node */
				UDF_VERBOSE_MAX(udf_dump_alloc_extent(alloc_ext_entry, addr_type));
				break;
			case TAGID_INDIRECTENTRY :
				printf("create_anon_udf_node called with indirect entry; following chain\n");
				l_ad = &dscrptr->inde.indirect_icb;
				next_alloc->len       = udf_rw32(l_ad->len);
				next_alloc->lb_num    = udf_rw32(l_ad->loc.lb_num);
				next_alloc->vpart_num = udf_rw16(l_ad->loc.part_num);
				entries   = 1;		/* at least one more entry	*/
				advance_sector = 0;	/* don't advance to next sector */

				UDF_VERBOSE_MAX(udf_dump_descriptor(dscrptr));
				break;
			default:
				printf("read_file_part_extents: i can't be here! (tag = %d) in ICB hiargy of %s\n", fe_tag, what);
				udf_dump_descriptor(dscrptr);
				return EFAULT;
		}
		if (fe_tag != TAGID_INDIRECTENTRY) {
			udf_node->addr_type = addr_type;
			if (addr_type == UDF_ICB_INTERN_ALLOC) {
				udf_node->intern_len  = inf_len;
				udf_node->intern_free = data_space_avail;
				udf_node->intern_data = calloc(1, udf_node->intern_free);
				if (udf_node->intern_data) {
					memcpy(udf_node->intern_data, pos, inf_len);
				} else {
					error = ENOMEM;
				}

				if (dscrptr != given_dscrptr) free(dscrptr);
				return error;
			}

			icb_len = 0;
			switch (udf_node->addr_type) {
				case UDF_ICB_SHORT_ALLOC :
					icb_len   = sizeof(struct short_ad);
					break;
				case UDF_ICB_LONG_ALLOC  :
					icb_len   = sizeof(struct long_ad);
					break;
				default :
					printf("UDF encountered an unknown allocation type %d\n", udf_node->addr_type);
					break;
			}
			udf_node->icb_len = icb_len;
			advance_sector = 1;
			while (icb_len && data_length) {
				switch (udf_node->addr_type) {
					case UDF_ICB_SHORT_ALLOC  :
						s_ad = (struct short_ad *) pos;
						len       = udf_rw32(s_ad->len);
						lb_num    = udf_rw32(s_ad->lb_num);
						vpart_num = cur_alloc->vpart_num;
						break;
					case UDF_ICB_LONG_ALLOC   :
						l_ad = (struct long_ad *) pos;
						len       = udf_rw32(l_ad->len);
						lb_num    = udf_rw32(l_ad->loc.lb_num);
						vpart_num = udf_rw16(l_ad->loc.part_num);
						if (l_ad->impl.im_used.flags & UDF_ADIMP_FLAGS_EXTENT_ERASED) {
							printf("UDF: got a `extent erased' flag in a file's long_ad; ignoring\n");
						}
						break;
					default :
						printf("UDF encountered an unknown allocation type %d\n", udf_node->addr_type);
						break;
				}
				/* ecma-167 48.14.1.1 */
				flags = (uint8_t) ((uint32_t) (len >> 30) & 3);
				len   = len & ((1<<30)-1);
				if (flags == UDF_SPACE_REDIRECT) {
					/* fill in next extent */
					next_alloc->len       = len;
					next_alloc->lb_num    = lb_num;
					next_alloc->vpart_num = vpart_num;
					advance_sector = 0;	/* don't advance to next sector */
					icb_len = data_length;	/* must be last */
					DEBUG(printf("Continuing extent flagged at vpart = %d, lb_num = %d, len = %d\n", (int) vpart_num, (int) lb_num, (int) len));
				} else {
					if (len) {
						alloc_entry = calloc(1, sizeof(struct udf_allocentry));
						if (!alloc_entry) {
							if (dscrptr != given_dscrptr) free(dscrptr);
							return ENOMEM;
						}
						alloc_entry->len       = len;
						alloc_entry->lb_num    = lb_num;
						alloc_entry->vpart_num = vpart_num;
						alloc_entry->flags     = flags;
						TAILQ_INSERT_TAIL(&udf_node->alloc_entries, alloc_entry, next_alloc);
					}
					calculated_len += len;
				}
				data_length  -= icb_len;
				pos          += icb_len;
			} /* while */
			if (advance_sector) {
				/* Note: UDF descriptor length is maximised to one sector */
				next_alloc->lb_num++;	/* advance one sector */
				entries--;
			}
		} /* indirect ICB check */
		if (entries) {
			/* load in new dscrptr */
			if (dscrptr != given_dscrptr) free(dscrptr);
			error = udf_read_logvol_descriptor(udf_log_vol, next_alloc->vpart_num, next_alloc->lb_num, what, &dscrptr, NULL);
		}
	} while (entries && !error);

	/* error from reading next sector in extent is not considered an error */
	if (dscrptr != given_dscrptr && dscrptr) free(dscrptr);

	if (calculated_len != (uint64_t) udf_node->stat.st_size) {
		printf("UDF: create node length mismatch; stated as %g but calculated as %g bytes. fixing\n", (double) udf_node->stat.st_size, (double) calculated_len);
		udf_node->stat.st_size = calculated_len;
	}

	return 0;
}


int udf_readin_udf_node(struct udf_node *dir_node, struct long_ad *udf_icbptr, struct fileid_desc *fid, struct udf_node **res_sub_node) {
	struct udf_node    *sub_node;
	char               *fid_name;
	char                entry_name[NAME_MAX];
	uint32_t            bucket;
	ino_t               hashkey;
	int                 error;

	assert(dir_node);
	assert(udf_icbptr);
	assert(fid);
	assert(res_sub_node);

	/* check if its allready in the logical volume's udf_node cache (inodes) */
	hashkey = udf_calc_hash(udf_icbptr);
	bucket  = hashkey & UDF_INODE_HASHMASK;

	LIST_FOREACH(sub_node, &dir_node->udf_log_vol->udf_nodes[bucket], next_node) {
		if (sub_node->hashkey == hashkey) {
			*res_sub_node = sub_node;
			DEBUG(printf("found node in hashlist\n"));

			return 0;
		}
	}

	/* dump the FID we are trying to read in */
	UDF_VERBOSE_MAX(udf_dump_descriptor((union dscrptr *) fid));

	fid_name = (char *) fid->data + udf_rw16(fid->l_iu);
	udf_to_unix_name(entry_name, fid_name, fid->l_fi, &dir_node->udf_log_vol->log_vol->desc_charset);

	/* build missing vnode */
	error = udf_readin_anon_udf_node(dir_node->udf_log_vol, NULL, udf_icbptr, entry_name, &sub_node);
	if (error)
		return error;

	if (!sub_node) {
		printf("sub_node = NULL? and no error? \n");
	}
	assert(sub_node);

	/* link this UDF node to the mountpoint and remember its hash-key */
	sub_node->mountpoint       = dir_node->mountpoint;
	sub_node->hashkey          = hashkey;

	/* XXX use file version number and filechar from fid ? */
	sub_node->file_version_num = udf_rw16(fid->file_version_num);	/* user set */
	sub_node->udf_filechar     = fid->file_char;

	/* insert/replace in mountpoint's udfnode hashtable with optional check for doubles */
if (0) {
		struct udf_node *lookup;
		LIST_FOREACH(lookup, &dir_node->udf_log_vol->udf_nodes[bucket], next_node) {
			if (lookup->hashkey == sub_node->hashkey) printf("DOUBLE hashnode?\n");
		}
}

	LIST_INSERT_HEAD(&dir_node->udf_log_vol->udf_nodes[bucket], sub_node, next_node);
	DEBUG(printf("inserting hash node for hash = %d\n", (int) hashkey));

	*res_sub_node = sub_node;
	return 0;
}


void udf_syncnode_callback(int reason, struct udf_wrcallback *wrcallback, int error, uint8_t *sectordata) {
	/* struct udf_node *udf_node = (struct udf_node *) wrcallback->structure; */

	wrcallback = wrcallback;	/* unused for now */
	sectordata = sectordata;

	if (reason == UDF_WRCALLBACK_REASON_PENDING) {
		/* what to do? */
		return;
	}
	if (reason == UDF_WRCALLBACK_REASON_ANULATE) {
		/* what to do? */
		return;
	}
	assert(reason == UDF_WRCALLBACK_REASON_WRITTEN);
	if (error) {
		printf("UDF error: syncnode writing failed, not fixing yet!\n");
		return;
	}
}


/* XXX This mark node dirty code will simplify if we store nodes in buffers? XXX */
void udf_node_mark_dirty(struct udf_node *udf_node) {
	struct udf_allocentry *alloc_entry, *my_entry, *tail_entry;
	struct udf_node *search_node, *tail_node;

	if (udf_node->dirty) return;

	my_entry = TAILQ_FIRST(&udf_node->dscr_allocs);
	assert(my_entry);

	/* dscr locks ? */
	UDF_MUTEX_LOCK(&udf_node->udf_log_vol->dirty_nodes_mutex);
if (1) {
		/* insertion sort :-S */
		tail_node  = TAILQ_LAST(&udf_node->udf_log_vol->dirty_nodes, udf_node_list);
		if (!tail_node) {
			TAILQ_INSERT_TAIL(&udf_node->udf_log_vol->dirty_nodes, udf_node, next_dirty);
		} else {
			tail_entry = TAILQ_FIRST(&tail_node->dscr_allocs);
			if (tail_entry->lb_num < my_entry->lb_num) {
				TAILQ_INSERT_TAIL(&udf_node->udf_log_vol->dirty_nodes, udf_node, next_dirty);
			} else {
				/* find my place; could be done smarter */
				TAILQ_FOREACH(search_node, &udf_node->udf_log_vol->dirty_nodes, next_dirty) {
					alloc_entry = TAILQ_FIRST(&tail_node->dscr_allocs);
					if (alloc_entry->lb_num > my_entry->lb_num) {
						TAILQ_INSERT_BEFORE(search_node, udf_node, next_dirty);
						break;	/* foreach */
					}
				}
			}
		}
} else {
		/* dumb */
		TAILQ_INSERT_TAIL(&udf_node->udf_log_vol->dirty_nodes, udf_node, next_dirty);
}
	UDF_MUTEX_UNLOCK(&udf_node->udf_log_vol->dirty_nodes_mutex);
	udf_node->dirty = 1;
}


static void udf_node_unmark_dirty(struct udf_node *udf_node) {
	if (!udf_node->dirty) return;

	/* remove me just in case; why were we called otherwise? */
	UDF_MUTEX_LOCK(&udf_node->udf_log_vol->dirty_nodes_mutex);
		TAILQ_REMOVE(&udf_node->udf_log_vol->dirty_nodes, udf_node, next_dirty);
	UDF_MUTEX_UNLOCK(&udf_node->udf_log_vol->dirty_nodes_mutex);
	udf_node->dirty = 0;
}


/* VOP_FSYNC : data FDATASYNC */
int udf_sync_udf_node(struct udf_node *udf_node, char *why) {

	DEBUG(printf("Syncing udf_node `%"PRIu64"` because of %s\n", udf_node->unique_id, why));
	DEBUG(printf("sync udf node: dirty = %d, v_numoutput = %d\n", udf_node->dirty, udf_node->v_numoutput));
	if (!udf_node->dirty) {
		/* Not dirty??!!! */
		udf_node_unmark_dirty(udf_node);
		return 0;
	}

	if (!udf_node->udf_log_vol->writable) {
		fprintf(stderr, "encountered a dirty node on a read-only filingsystem!\n");
		exit(1);
	}

	/*
	 * We are really syncing disc but we are only continueing when the
	 * node itself is clean... not breaking the semantics.
	 */
	/* XXX flushall flag magic XXX */
	udf_bufcache->flushall = 1;
	udf_purgethread_kick("Sync node");
	fflush(stdout);

	/* wait until all dirty bufs associated with this node are processed */
	if (!udf_node->dirty) return 0;

	if (udf_node->v_numoutput) {
		usleep(100);
	}
	if (!udf_node->v_numoutput) return 0;

	UDF_VERBOSE(printf("(wait on node)"));
	while (udf_node->v_numoutput) {
		usleep(100);
	}

	return 0;
}


extern void udf_merge_allocentry_queue(struct udf_alloc_entries *queue, uint32_t lb_size);

/* VOP_FSYNC : metadata FFILESYNC */
/* writeout the udf_node back to disc */
/* TODO don't forget to writeout our extended attributes and write out the link to the associated streamdir as well */
int udf_writeout_udf_node(struct udf_node *udf_node, char *why) {
	struct udf_wrcallback   wr_callback;
	struct udf_allocentry  *dscr_entry, *next_dscr_entry, *alloc_entry;
	union dscrptr          *dscrptr;
	struct file_entry      *fe;
	struct extfile_entry   *efe;
	struct alloc_ext_entry *aee;
	struct lb_addr          parent_icb;
	struct icb_tag         *icbtag;
	struct long_ad         *l_ad;
	struct short_ad        *s_ad;
	uint32_t               *l_adptr;	/* points to length of alloc. descr. */
	uint8_t                *pos;
	char                   *what;
	uint32_t                alloc_entries;
	uint64_t                rest;		/* in bytes */
	uint64_t                len;
	uint64_t                logblks_rec;
	uint32_t		lb_size, descr_ver;

	if (!udf_node->udf_log_vol->writable) {
		fprintf(stderr, "encountered a dirty node on a read-only filingsystem!\n");
		exit(1);
	}

	lb_size     = udf_node->udf_log_vol->lb_size;

	/* assure all file data is written out! and clean up */
	udf_sync_udf_node(udf_node, why);

	/* XXX node lock? XXX */

	UDF_MUTEX_LOCK(&udf_node->alloc_mutex);
		/* clean up allocentry queue so we get a nice clean layout */
		udf_merge_allocentry_queue(&udf_node->alloc_entries, lb_size);
	UDF_MUTEX_UNLOCK(&udf_node->alloc_mutex);

	/* allocate for descriptor */
	dscrptr = calloc(1, lb_size);	/* not a bit biggish? */
	if (!dscrptr) return ENOMEM;

	/* calculate logical blocks recorded; zero for interns [UDF 2.3.6.5, ECMA 4/14.9.11, 4/14.6.8] */
	logblks_rec = 0;
	if (udf_node->addr_type != UDF_ICB_INTERN_ALLOC) {
		UDF_MUTEX_LOCK(&udf_node->alloc_mutex);
			TAILQ_FOREACH(alloc_entry, &udf_node->alloc_entries, next_alloc) {
				if (alloc_entry->flags == UDF_SPACE_ALLOCATED) {
					logblks_rec += (alloc_entry->len + lb_size-1) / lb_size;
				}
			}
		UDF_MUTEX_UNLOCK(&udf_node->alloc_mutex);
	}

	/* fill in (ext)fentry descriptor */
	/* copy descriptor version from the logvol's */

	bzero(&parent_icb, sizeof(struct lb_addr));
	descr_ver = udf_rw16(udf_node->udf_log_vol->log_vol->tag.descriptor_ver);
	if (descr_ver == 3) {
		efe = &dscrptr->efe;
		efe->tag.id             = udf_rw16(TAGID_EXTFENTRY);
		efe->tag.descriptor_ver = udf_rw16(descr_ver);
		efe->ckpoint            = udf_rw32(1);			/* [ECMA 4/14.17.17] */
		udf_set_imp_id(&efe->imp_id);
		efe->logblks_rec = udf_rw64(logblks_rec);

		/* set additional fileinfo (access, uid/gid) etc. */
		udf_node_set_fileinfo(udf_node, dscrptr);
		efe->obj_size           = efe->inf_len;			/* not true if there are streams [ECMA 4/48.17.11] */

		icbtag = &efe->icbtag;
	} else if (descr_ver == 2) {
		fe = &dscrptr->fe;
		fe->tag.id             = udf_rw16(TAGID_FENTRY);
		fe->tag.descriptor_ver = udf_rw16(descr_ver);
		fe->ckpoint            = udf_rw32(1);			/* [ECMA 4/14.17.17] */
		udf_set_imp_id(&fe->imp_id);
		fe->logblks_rec = udf_rw64(logblks_rec);

		/* set additional fileinfo (access, uid/gid) etc. */
		udf_node_set_fileinfo(udf_node, dscrptr);
		/* fe->obj_size doesn't exist */

		icbtag = &fe->icbtag;
	} else {
		printf("UDF: i don't know this descriptor version %d\n", descr_ver);
		free(dscrptr);
		return EBADF;
	}

	/* update derived info */
	udf_node->udf_icbtag_flags = (udf_node->udf_icbtag_flags & ~UDF_ICB_TAG_FLAGS_ALLOC_MASK) | udf_node->addr_type;

	/* strategy 4 has no parent nodes */
	/* XXX NO extended attributes recorded YET (!!) XXX (like device nodes !!! ) */

	dscr_entry  = TAILQ_FIRST(&udf_node->dscr_allocs);

	/* ensure allocation of (ext) file descriptor */
	if (!dscr_entry) {
		/* have to allocate one and add to queue ! */
		printf("UDF: XXX no allocation of file descriptor entry yet in sync_udf_node\n");
		return ENOENT;
	}

	/* XXX implement alloc entry walker? XXX */
	UDF_MUTEX_LOCK(&udf_node->alloc_mutex);
	what = "UDF sync: File descriptor";
	alloc_entry = TAILQ_FIRST(&udf_node->alloc_entries);
	do {
		assert(dscr_entry->len <= lb_size);
		if (icbtag) {
			/* fill in ICB fields */			/* XXX we're only writing out strategy type 4 !!! XXX */
			icbtag->prev_num_dirs   = udf_rw32(0);		/* prev_alloc_entries = 0 due to strategy type 4 XXX */
			icbtag->strat_type      = udf_rw16(4);		/* default UDF strategy type 4 XXX what about 4096? */
			icbtag->parent_icb      = parent_icb;
			icbtag->file_type       = udf_node->udf_filetype;
			icbtag->flags           = udf_rw16(udf_node->udf_icbtag_flags);
			icbtag->max_num_entries = udf_rw16(1);		/* due to strategy type 4 ! XXX */
		}

		pos  = 0;
		rest = 0;
		l_adptr = NULL;		/* invalid */
		switch (udf_rw16(dscrptr->tag.id)) {
			case TAGID_FENTRY         :
				/* not used now */
				fe   = &dscrptr->fe;
				pos  = &fe->data[0] + udf_rw32(fe->l_ea);
				rest = dscr_entry->len - sizeof(struct file_entry) - udf_rw32(fe->l_ea);
				l_adptr = &fe->l_ad;
				break;
			case TAGID_EXTFENTRY      :
				efe  = &dscrptr->efe;
				pos  = &efe->data[0] + udf_rw32(efe->l_ea);
				rest = dscr_entry->len - sizeof(struct extfile_entry) - udf_rw32(efe->l_ea);
				l_adptr = &efe->l_ad;
				break;
			case TAGID_ALLOCEXTENT    :
				aee  = &dscrptr->aee;
				pos  = &aee->data[0];
				rest = dscr_entry->len - sizeof(struct alloc_ext_entry);
				l_adptr = &aee->l_ad;
				break;
			case TAGID_INDIRECTENTRY :
				/* do we even do these in strat 4 ? */
				printf("UDF: sanity check; request for writeout of indirect entry\n");
				free(dscrptr);
				UDF_MUTEX_UNLOCK(&udf_node->alloc_mutex);
				return ENOENT;	/* panic really */
		}
		assert(l_adptr);

		/* fill in remaining allocation entries 	*/
		/* remember to keep one SPARE for extending	*/

		alloc_entries = 0;
		DEBUG(printf("Allocated at "));

		if (udf_node->addr_type == UDF_ICB_INTERN_ALLOC) {
			/* internal allocation -> copy in data */
			assert(udf_node->intern_len <= rest);

			bzero(pos, rest);
			memcpy(pos, udf_node->intern_data, udf_node->intern_len);

			/* make sure the length for allocation entries is the same as the data it contains (4/8.8.2, 4/14.6.8) */
			*l_adptr = udf_rw32(udf_node->intern_len);

			/* alloc_entry is zero, so it'll fall trough */
			pos	+= udf_node->intern_len;	/* advance pos for length calculation */
			alloc_entry = NULL;			/* not applicable */
		}

		while ((rest > 2*udf_node->icb_len) && alloc_entry) {
			assert(udf_node->icb_len);
			DEBUG(printf("[%p, lb_num = %d, len = %d]   ", alloc_entry, (uint32_t) alloc_entry->lb_num, (uint32_t) alloc_entry->len));

			/* XXX assumption: UDF_SPACE_* is equal to UDF flags XXX */
			len = alloc_entry->len | (((uint32_t) alloc_entry->flags) << 30);
			switch (udf_node->addr_type) {
				case UDF_ICB_SHORT_ALLOC :
					s_ad = (struct short_ad *) pos;
					s_ad->len          = udf_rw32(len);
					s_ad->lb_num       = udf_rw32(alloc_entry->lb_num);
					assert(alloc_entry->vpart_num == 0);
					if (alloc_entry->len   == 0)              s_ad->lb_num = udf_rw32(0);
					if (alloc_entry->flags == UDF_SPACE_FREE) s_ad->lb_num = udf_rw32(0);
					break;
				case UDF_ICB_LONG_ALLOC  :
					l_ad = (struct long_ad *) pos;
					l_ad->len          = udf_rw32(len);
					l_ad->loc.lb_num   = udf_rw32(alloc_entry->lb_num);
					l_ad->loc.part_num = udf_rw16(alloc_entry->vpart_num);
					l_ad->impl.im_used.unique_id = udf_rw64(udf_node->unique_id);
					if (alloc_entry->len   == 0)              l_ad->loc.lb_num = udf_rw32(0);
					if (alloc_entry->flags == UDF_SPACE_FREE) l_ad->loc.lb_num = udf_rw32(0);
					break;
			}
			alloc_entries++;
			*l_adptr = udf_rw32(alloc_entries * udf_node->icb_len);
			alloc_entry = TAILQ_NEXT(alloc_entry, next_alloc);
			pos  += udf_node->icb_len;
			rest -= udf_node->icb_len;
		}
		DEBUG(printf("\nend alloc\n\n"));

		next_dscr_entry = TAILQ_NEXT(dscr_entry, next_alloc);
		if (alloc_entry) {
			/* overflow */

			/* ensure allocation of (ext) file descriptor */
			if (!next_dscr_entry) {
				/* have to allocate one and add to queue ! */
				printf("UDF: XXX no allocation of allocation extent descriptor yet in sync_udf_node\n");
				UDF_MUTEX_UNLOCK(&udf_node->alloc_mutex);
				return ENOENT;
			}
			/* flag next extent being specified */
			len = next_dscr_entry->len | ((uint32_t) UDF_SPACE_REDIRECT << 30);
			switch (udf_node->addr_type) {
				case UDF_ICB_SHORT_ALLOC :
					s_ad = (struct short_ad *) pos;
					s_ad->len          = udf_rw32(len);
					s_ad->lb_num       = udf_rw32(next_dscr_entry->lb_num);
					assert(next_dscr_entry->vpart_num == 0);
					break;
				case UDF_ICB_LONG_ALLOC  :
					l_ad = (struct long_ad *) pos;
					l_ad->len          = udf_rw32(len);
					l_ad->loc.lb_num   = udf_rw32(next_dscr_entry->lb_num);
					l_ad->loc.part_num = udf_rw16(next_dscr_entry->vpart_num);
					l_ad->impl.im_used.unique_id = udf_rw64(udf_node->unique_id);
					break;
			}
			alloc_entries++;
			pos  += udf_node->icb_len;
			rest -= udf_node->icb_len;
		}
		/* manage lengths */
		dscrptr->tag.desc_crc_len = udf_rw16((pos - (uint8_t *) dscrptr) - UDF_DESC_TAG_LENGTH);

		/* writeout */
		wr_callback.function  = udf_syncnode_callback;
#if 0
		wr_callback.structure = (void *) udf_node;
		wr_callback.vpart_num = dscr_entry->vpart_num;
		wr_callback.lb_num    = dscr_entry->lb_num;
		wr_callback.offset    = 0; /* ? */
		wr_callback.length    = dscr_entry->len;
#endif

		UDF_VERBOSE_MAX(
			udf_validate_tag_and_crc_sums(dscrptr);	/* for dumping */
			udf_dump_descriptor(dscrptr);
		);
		errno = udf_write_logvol_descriptor(udf_node->udf_log_vol, dscr_entry->vpart_num, dscr_entry->lb_num, what, dscrptr, &wr_callback);

		/* advance */
		if (alloc_entry) {
			dscr_entry = next_dscr_entry;
			assert(dscr_entry);

			/* allocate and initialise new allocation extent descriptor	*/
			/* also flag no icbtag follows					*/
			bzero(dscrptr, lb_size);
			aee = &dscrptr->aee;
			aee->tag.id             = udf_rw16(TAGID_ALLOCEXTENT);
			aee->tag.descriptor_ver = udf_node->udf_log_vol->log_vol->tag.descriptor_ver;
			icbtag = NULL;

			what = "UDF sync: allocation extent";
		}

	} while (alloc_entry);
	UDF_MUTEX_UNLOCK(&udf_node->alloc_mutex);

	/* XXX Free extra non used allocation extent descriptors XXX */

	/* Mark me clean */
	if (udf_node->mountpoint) {
		/* remove me just in case; why were we called otherwise? */
		udf_node_unmark_dirty(udf_node);
	}

	return 0;
}


/******************************************************************************************
 *
 * Space bitmap reader and writer 
 *
 ******************************************************************************************/

/* tested OK */
int udf_read_in_space_bitmap(struct udf_alloc_entries *queue, struct space_bitmap_desc *sbd, uint32_t lb_size, uint64_t *freespace) {
	struct udf_allocentry *alloc_entry;
	uint64_t bits, from, now, start, end;
	uint8_t byte, bit, bitpos, state, *pos;
	int cnt;

	assert(udf_rw16(sbd->tag.id) == TAGID_SPACE_BITMAP);

	DEBUG(printf("processing space bitmap : \n"););
	bits = udf_rw32(sbd->num_bits);

	/*
	 * Mark the disc as completely full;
	 * Bugallert: use `udf_mark_allocentry_queue()' for the extent might
	 * not fit in just one alloc entry for bigger discs
	 */
	assert(TAILQ_EMPTY(queue));
	udf_mark_allocentry_queue(queue, lb_size, 0, bits * lb_size, UDF_SPACE_ALLOCATED, NULL, NULL);

	pos = sbd->data;
	from = 0; now = 0; bitpos = 0; byte = *pos; state = byte & 1;
	*freespace = 0;
	while (now < bits) {
		if (bitpos == 0) {
			byte = *pos++;
		}
		bit = byte & 1;
		if (bit != state) {
			if (state) {
				start = from;
				end   = now-1;
				/* printf("[%08d - %08d]", start, end); */
				udf_mark_allocentry_queue(queue, lb_size, start*lb_size, (end-start+1)*lb_size, UDF_SPACE_FREE, NULL, NULL);
				*freespace += (end-start+1)*lb_size;
			}
			from = now;
			state = bit;
		}
		byte >>= 1;
		bitpos = (bitpos+1) & 7;
		now++;
	}
	if (state) {
		start = from;
		end   = now;
		/* printf("[%08d - %08d]", start, end); */
		udf_mark_allocentry_queue(queue, lb_size, start*lb_size, (end-start)*lb_size, UDF_SPACE_FREE, NULL, NULL);
		*freespace += (end-start)*lb_size;
	}

	UDF_VERBOSE_TABLES(
		printf("\t\tFree space found on this partition");
		cnt = 0;
		start = 0;
		TAILQ_FOREACH(alloc_entry, queue, next_alloc) {
			if (alloc_entry->flags == UDF_SPACE_ALLOCATED) {
				/* printf("... "); */
			} else {
				if (cnt == 0) printf("\n\t\t\t");
				printf("[%08"PRIu64" - %08"PRIu64"]   ", start / lb_size, ((start + alloc_entry->len) / lb_size)-1);
				cnt++; if (cnt > 4) cnt = 0;
			}
			start += alloc_entry->len;
		}
		printf("\n");
	);

	/* merge is not nessisary */
	return 0;
}


/* inverse of readin space bitmap; it synchronises the bitmap with the queue */
/* tested OK */
int udf_sync_space_bitmap(struct udf_alloc_entries *queue, struct space_bitmap_desc *sbd, uint32_t lb_size) {
	struct udf_allocentry *alloc_entry;
	uint32_t start, bits, total_bits;
	uint32_t cnt, byte;
	uint8_t  bit, bitmask, setting;
	uint8_t *pos;

	/* merge it just in case */
	udf_merge_allocentry_queue(queue, lb_size);

	total_bits = udf_rw32(sbd->num_bits);
	DEBUG(printf("SYNC SPACE BITMAP DEBUG: total bits = %d\n", total_bits));

	alloc_entry = TAILQ_FIRST(queue);
	start = alloc_entry->lb_num;
	assert(start == 0);

	TAILQ_FOREACH(alloc_entry, queue, next_alloc) {
		DEBUG(printf(" [%d : %d + %d]", alloc_entry->flags, alloc_entry->lb_num, alloc_entry->len));
		bits  = alloc_entry->len / lb_size;
		assert(bits*lb_size == alloc_entry->len);

		byte = start / 8;
		bit  = start - byte*8;

		pos = sbd->data + byte;

		if (byte*8 + bit + bits > total_bits) {		/* XXX > or >= ? */
			/* this should NEVER happen */
			printf("UDF: not enough space writing back space bitmap! HELP!\n");
			return EBADF;
		}

		cnt = 0;
		setting = (alloc_entry->flags != UDF_SPACE_FREE) ? 0 : 255;
		while (cnt < bits) {
			bitmask = (1 << bit);

			/* simple sanity check */
			if (byte*8 + bit >= total_bits) {
				printf("IEEEE!!!! too big; %d instead of %d\n", (byte*8 + bit), total_bits);
			}
			*pos = (*pos & (~bitmask)) | (setting ? bitmask: 0);

			cnt++;
			bit++;
			if (bit == 8) {
				/* byte transition */
				byte++; bit = 0;
				pos++;
#if 0
				/* speedup by doing bytes at a time */
				while (bits-cnt > 8) {
					*pos = setting;
					cnt += 8;
					pos++; byte++;
				}
#endif
			}
		}
		start += bits;
	}
	DEBUG(printf("\n\n"));
	return 0;
}



/******************************************************************************************
 *
 * Filepart readers and writers 
 *
 ******************************************************************************************/

/* part of VOP_STRATEGY */
/* internal function; reads in a new buffer */
/* !!! bufcache lock ought to be held on entry !!! */
int udf_readin_file_buffer(struct udf_node *udf_node, char *what, uint32_t sector, int cache_flags, struct udf_buf **buf_entry_p) {
	struct udf_allocentry *alloc_entry;
	struct udf_buf	*buf_entry;
	uint64_t         cur_offset;
	uint64_t         overlap_length, overlap_sectors, transfer_length;
	uint32_t	 lb_size;
	uint32_t         len, lb_num, vpart_num;
	int32_t	         error;
	uint8_t	         flags;

	assert(udf_node);
	assert(buf_entry_p);
	assert(udf_bufcache->bufcache_lock.locked);

	error = udf_get_buf_entry(udf_node, buf_entry_p);
	if (error) return error;

	buf_entry = *buf_entry_p;
	lb_size   = udf_node->udf_log_vol->lb_size;

	/* internal node? */
	if (udf_node->addr_type == UDF_ICB_INTERN_ALLOC) {
		buf_entry->b_lblk    = 0;
		buf_entry->b_flags   = 0;				/* not dirty, not needing alloc */
		buf_entry->b_bcount  = udf_node->intern_len;
		buf_entry->b_resid   = lb_size - udf_node->intern_len;

		memcpy(buf_entry->b_data, udf_node->intern_data, udf_node->intern_len);

		UDF_MUTEX_LOCK(&udf_node->buf_mutex);
			udf_attach_buf_to_node(udf_node, buf_entry);
		UDF_MUTEX_UNLOCK(&udf_node->buf_mutex);
		return error;
	}

	/* `normal' node */

	/* find sector in the allocation space */
	UDF_MUTEX_LOCK(&udf_node->alloc_mutex);
	cur_offset = 0;
	error = EIO;	/* until proven readable */
	TAILQ_FOREACH(alloc_entry, &udf_node->alloc_entries, next_alloc) {
		len       = alloc_entry->len;
		lb_num    = alloc_entry->lb_num;
		vpart_num = alloc_entry->vpart_num;
		flags     = alloc_entry->flags;

		/* check overlap with this alloc entry */
		if (cur_offset + len > sector * lb_size) {
			/* found an extent that fits */
			assert(((sector * lb_size - cur_offset) % lb_size) == 0);	/* ought to be on sector boundary */
			lb_num += sector - (cur_offset / lb_size);

			overlap_length  = cur_offset + len - sector * lb_size;
			overlap_sectors = (overlap_length + lb_size -1) / lb_size;
			transfer_length = MIN(lb_size, overlap_length);			/* max one logical sector */

			/* fill in new buf info */
			buf_entry->b_lblk   = sector;
			buf_entry->b_bcount = transfer_length;
			buf_entry->b_resid  = lb_size - transfer_length;

			/* sector transfered; mark valid */
			buf_entry->b_flags  = 0;		/* not dirty and valid */

			switch (flags) {
				case UDF_SPACE_ALLOCATED :
					/* on disc or in the write queue/cache to be written out; read one block at a time */
					error = udf_read_logvol_sector(udf_node->udf_log_vol, vpart_num, lb_num, what, buf_entry->b_data, overlap_sectors, cache_flags);
					break;
				case UDF_SPACE_FREE :
					/* fall trough */
				case UDF_SPACE_ALLOCATED_BUT_NOT_USED :
					error = 0;
					bzero(buf_entry->b_data, lb_size);
					break;
				default :
					fprintf(stderr, "Got an redirect flag, can't happen\n");
					break;
			}

			if (error) {
				fprintf(stderr, "\tgot error from read_logvol_sector : %s\n", strerror(error));
				break;	/* FOREACH */
			}

			UDF_MUTEX_LOCK(&udf_node->buf_mutex);
				udf_attach_buf_to_node(udf_node, buf_entry);
			UDF_MUTEX_UNLOCK(&udf_node->buf_mutex);

			UDF_MUTEX_UNLOCK(&udf_node->alloc_mutex);
			return 0;

		} /* looking for overlap */

		cur_offset += len;
	} /* FOREACH */
	UDF_MUTEX_UNLOCK(&udf_node->alloc_mutex);

	*buf_entry_p = NULL;

	udf_mark_buf_clean(udf_node, buf_entry);	/* its destroyed so not dirty */
	udf_mark_buf_allocated(udf_node, buf_entry);	/* i.e. taken care of */
	udf_free_buf_entry(buf_entry);
	return error;
}


/* internal function; shedule writing out of a buffer */
/* part of VOP_STRATEGY */
int udf_writeout_file_buffer(struct udf_node *udf_node, char *what, int cache_flags, struct udf_buf *buf_entry) {
	struct udf_allocentry *from_alloc, *to_alloc, *alloc_entry;
	uint32_t lb_num, lb_size, lblk;
	uint16_t vpart_num;
	int error;

	what = what;	/* not used now */

	if (!udf_node->udf_log_vol->writable) {
		/* ieek */
		fprintf(stderr, "write request from non writable file buffer?\n");
	}

	/* first get logical block offset and block size */
	lblk = buf_entry->b_lblk;
	lb_size = udf_node->udf_log_vol->lb_size;

	error = 0;
	UDF_MUTEX_LOCK(&udf_bufcache->bufcache_lock);
	UDF_MUTEX_LOCK(&udf_node->alloc_mutex);
	UDF_MUTEX_LOCK(&udf_node->buf_mutex);
		/* maybe a bit too strict locking; code is not winning the beauty contest  */

		/* check if we can convert/save disc space */
		if (udf_node->stat.st_size <= udf_node->intern_free) {
			/* convert to internal alloc with backup storage (writing there) */
			if (udf_node->addr_type != UDF_ICB_INTERN_ALLOC) {
				DEBUG(printf("CONVERTING to intern alloc\n"));
				/* first free all previously allocated sectors (if any) */
				error = udf_node_release_extent(udf_node, 0, udf_node->stat.st_size);
			}
			assert(!error);
			if (!udf_node->intern_data) {
				udf_node->intern_data = calloc(1, udf_node->intern_free);
			}
			if (udf_node->intern_data) {
				assert(buf_entry->b_bcount <= udf_node->intern_free);

				memcpy(udf_node->intern_data, buf_entry->b_data, buf_entry->b_bcount);
				udf_node->intern_len = buf_entry->b_bcount;
				udf_node->addr_type = UDF_ICB_INTERN_ALLOC;

				/* we don't write here: mark buffer clean */
				udf_mark_buf_clean(udf_node, buf_entry);
				udf_mark_buf_allocated(udf_node, buf_entry);		/* signal its allocated */
				buf_entry->b_flags &= ~(B_ERROR);

				/* check if all buffers are gone now and mark node for writeout to indicate state change */
				assert(udf_node->v_numoutput == 0);
				udf_node_mark_dirty(udf_node);

				UDF_MUTEX_UNLOCK(&udf_node->buf_mutex);
				UDF_MUTEX_UNLOCK(&udf_node->alloc_mutex);
				UDF_MUTEX_UNLOCK(&udf_bufcache->bufcache_lock);
				return 0;
			}
			/* fall trough ... for some reason it isn't converted */
		} else {
			if (udf_node->addr_type == UDF_ICB_INTERN_ALLOC) {
				DEBUG(printf("CONVERTING to normal alloc\n"));
				/* won't fit anymore, have to turn it into a `normal' alloced */
				udf_node->intern_len = 0;
				if (udf_node->intern_data)
					free(udf_node->intern_data);
				udf_node->intern_data = NULL;
				udf_node->icb_len   = sizeof(struct long_ad);
				udf_node->addr_type = UDF_ICB_LONG_ALLOC;

				udf_node_mark_dirty(udf_node);

				/* mark needalloc to make sure it gets an address */
				udf_mark_buf_needing_allocate(udf_node, buf_entry);	/* signal it needs allocation */
			}
		}

		/* merge queue first to get better performance */
		udf_merge_allocentry_queue(&udf_node->alloc_entries, lb_size);

		/* get extent that it represents */
		udf_mark_allocentry_queue(&udf_node->alloc_entries, lb_size, (uint64_t) lblk*lb_size, buf_entry->b_bcount, UDF_SPACE_ALLOCATED, &from_alloc, &to_alloc);
		alloc_entry = from_alloc;
		if (buf_entry->b_flags & B_NEEDALLOC) {
			/* need allocation */
			error = udf_node_allocate_lbs(udf_node, /* num lb */ 1, &vpart_num, &lb_num, NULL);
			assert(!error);
			udf_mark_buf_allocated(udf_node, buf_entry);
	
			alloc_entry->lb_num    = lb_num;
			alloc_entry->vpart_num = vpart_num;
		}
		assert(TAILQ_NEXT(alloc_entry, next_alloc) == to_alloc || (alloc_entry == to_alloc));

		lb_num    = alloc_entry->lb_num;
		vpart_num = alloc_entry->vpart_num;
	UDF_MUTEX_UNLOCK(&udf_node->buf_mutex);
	UDF_MUTEX_UNLOCK(&udf_node->alloc_mutex);
	UDF_MUTEX_UNLOCK(&udf_bufcache->bufcache_lock);

	/* printf("writing out filebuffer vpart %d, lb_num %d for %s\n", vpart_num, lb_num, what); */
	error = udf_write_logvol_sector(udf_node->udf_log_vol, vpart_num, lb_num, "File contents", buf_entry->b_data, cache_flags, NULL);

	UDF_MUTEX_LOCK(&udf_bufcache->bufcache_lock);
	UDF_MUTEX_LOCK(&udf_node->buf_mutex);
		if (error) {
			printf("YIKES error during writing of logvol_sector\n");
			udf_mark_buf_needing_allocate(udf_node, buf_entry);
			buf_entry->b_flags |= B_ERROR;
			/* buf_entry->b_errno = error; */
		} else {
			udf_mark_buf_clean(udf_node, buf_entry);
			buf_entry->b_flags &= ~(B_ERROR);
		}
	UDF_MUTEX_UNLOCK(&udf_node->buf_mutex);
	UDF_MUTEX_UNLOCK(&udf_bufcache->bufcache_lock);

	return error;
}


/* VOP_READ */
int udf_read_file_part_uio(struct udf_node *udf_node, char *what, int content, struct uio *data_uio) {
	struct udf_buf	*buf_entry;
	off_t  offset;
	uint64_t  sector, lb_size, data_length;
	uint8_t  *base;
	int error, short_buf;

	if (!udf_node) return EINVAL;

	/* NOTE: we are NOT marking the node dirty only by reading it */
	udf_set_timespec_now(&udf_node->stat.st_atimespec);

	if (udf_node->stat.st_size == 0) {
		if (data_uio->uio_resid) return EIO; /* reading past end by default */
		return 0;
	}

	lb_size = udf_node->udf_log_vol->lb_size;
	error = 0;
	while (data_uio->uio_resid) {
		error = 0;
		short_buf = 0;
		sector  = data_uio->uio_offset / lb_size;

		/* lookup sector in buffer set */
		UDF_MUTEX_LOCK(&udf_bufcache->bufcache_lock);
			udf_lookup_node_buf(udf_node, sector, &buf_entry);

			if (!buf_entry || (buf_entry && (buf_entry->b_lblk != sector))) {
				/* `page in' sector from file */
				error = udf_readin_file_buffer(udf_node, what, sector, content, &buf_entry);
			}

			if (!error && buf_entry) {
				offset = data_uio->uio_offset - (off_t) sector*lb_size;
				base   = buf_entry->b_data;
				if (offset >= 0) {
					data_length = buf_entry->b_bcount - offset;
					data_length = MIN(data_length, data_uio->uio_resid);
					uiomove(base + offset, data_length, data_uio);
				}
				short_buf = (buf_entry->b_bcount < lb_size);	/* short buf -> none will follow */
			}
			assert(!error || (error && !buf_entry));
		UDF_MUTEX_UNLOCK(&udf_bufcache->bufcache_lock);
		if (error) break; /* while */

		if (data_uio->uio_resid == 0) return 0;		/* finished? */
		if (short_buf) break;				/* while */
	} /* while */

	if (data_uio->uio_resid) {
		printf("UDF: WARNING file is truncated; missing %d bytes while reading %s\n",
				(int) data_uio->uio_resid, what);
		return EIO;
	}

	return error;
}


/* XXX meaning is to be changed; kept for reference still XXX */
void udf_filepart_write_callback(int reason, struct udf_wrcallback *wrcallback, int error, uint8_t *sectordata) {
	/* struct udf_node *udf_node = (struct udf_node *) wrcallback->structure; */

	wrcallback = wrcallback;	/* unused for now */
	sectordata = sectordata;

	if (reason == UDF_WRCALLBACK_REASON_PENDING) {
		/* what to do? */
		return;
	}
	if (reason == UDF_WRCALLBACK_REASON_ANULATE) {
		/* what to do? */
		return;
	}
	assert(reason == UDF_WRCALLBACK_REASON_WRITTEN);
	if (error) {
		printf("UDF error: file part write failed, not fixing yet!\n");
		return;
	}
}


/* VOP_TRUNCATE */
/* doesn't lock udf_node */
int udf_truncate_node(struct udf_node *udf_node, uint64_t length /* ,ioflags */) {
	struct udf_log_vol    *udf_log_vol;
	struct udf_allocentry *alloc_entry, *cut_point;
	struct udf_buf        *buf_entry, *marker;
	uint32_t lb_size;
	uint64_t cur_extent, block_extent, new_extent, too_much;
	uint32_t last_sector;
	int32_t	 error;

	if (!udf_node) return EINVAL;

	if (udf_open_logvol(udf_node->udf_log_vol))
		return EROFS;

	udf_log_vol = udf_node->udf_log_vol;
	lb_size     = udf_log_vol->lb_size;

	/* we might change this node AND access times ... */
	if (!udf_node->dirty) {
		/* mark node as dirty */
		udf_node_mark_dirty(udf_node);
	}

/* XXX lock node !!! XXX */

	/* merge known allocation entry queue */
	new_extent   = length;
	block_extent = (uint64_t) lb_size * ((new_extent + lb_size-1) / lb_size);	/* inclusive */
	too_much     = block_extent - new_extent;
	assert(block_extent >= new_extent);

	UDF_MUTEX_LOCK(&udf_bufcache->bufcache_lock);
	UDF_MUTEX_LOCK(&udf_node->alloc_mutex);
		udf_merge_allocentry_queue(&udf_node->alloc_entries, lb_size);

		/* extend the file when nessisary */
		if (new_extent > (uint64_t) udf_node->stat.st_size) {
			if (udf_node->addr_type == UDF_ICB_INTERN_ALLOC) {
				/* XXX to seperate function XXX */
				/* grow intern node by converting it to a normal buffer first */
				/* First lookup if the node already had a buffer associated */
				udf_lookup_node_buf(udf_node, 0, &buf_entry);
				if (!buf_entry) {
					error = udf_get_buf_entry(udf_node, &buf_entry);
					if (error) {
						UDF_MUTEX_UNLOCK(&udf_node->alloc_mutex);
						UDF_MUTEX_UNLOCK(&udf_bufcache->bufcache_lock);
						return error;
					}
					buf_entry->b_lblk   = 0;
					buf_entry->b_flags  = 0;

					UDF_MUTEX_LOCK(&udf_node->buf_mutex);
						udf_attach_buf_to_node(udf_node, buf_entry);
					UDF_MUTEX_UNLOCK(&udf_node->buf_mutex);
				} else {
					DEBUG(printf("found buffer associated with intern node!\n"));
				}

				buf_entry->b_bcount = MIN(lb_size, new_extent);
				buf_entry->b_resid  = lb_size - buf_entry->b_bcount;

				memcpy(buf_entry->b_data, udf_node->intern_data, udf_node->intern_len);
				memset(buf_entry->b_data + udf_node->intern_len, 0, lb_size - udf_node->intern_len);

				UDF_MUTEX_LOCK(&udf_node->buf_mutex);
					udf_mark_buf_dirty(udf_node, buf_entry);
				UDF_MUTEX_UNLOCK(&udf_node->buf_mutex);

				udf_node->intern_len = 0;
				if (udf_node->intern_data)
					free(udf_node->intern_data);
				udf_node->intern_data = NULL;
				udf_node->icb_len   = sizeof(struct long_ad);
				udf_node->addr_type = UDF_ICB_LONG_ALLOC;
			}
			udf_cut_allocentry_queue(&udf_node->alloc_entries, lb_size, block_extent);
			if (new_extent < block_extent) {
				alloc_entry = TAILQ_LAST(&udf_node->alloc_entries, udf_alloc_entries);
				assert(alloc_entry->len > too_much);

				alloc_entry->len -= too_much;
			}
			/* XXX Andrey suggested buffer extension? XXX */
			udf_node->stat.st_size = new_extent;
		}
	UDF_MUTEX_UNLOCK(&udf_node->alloc_mutex);
	UDF_MUTEX_UNLOCK(&udf_bufcache->bufcache_lock);

	/* `free' the extent when shrinking the extent */
	if (new_extent < (uint64_t) udf_node->stat.st_size) {
		DEBUG(printf("TRIMMING file %"PRIu64" from %d to %d\n", udf_node->unique_id, (int32_t) udf_node->stat.st_size, (uint32_t) length));

		/* free file buffers that are not needed anymore */
		/* XXX NetBSD kernel : uvm_vnp_setsize() XXX */
		marker = calloc(1, sizeof(struct udf_buf));
		if (!marker) return ENOMEM;

		UDF_MUTEX_LOCK(&udf_bufcache->bufcache_lock);
		UDF_MUTEX_LOCK(&udf_node->buf_mutex);
			/* use marker as we are going to delete items in the list we are traversing */
			last_sector = new_extent / lb_size;
			TAILQ_INSERT_HEAD(&udf_node->vn_bufs, marker, b_vnbufs);
			while ((buf_entry = TAILQ_NEXT(marker, b_vnbufs))) {
				/* advance marker */
				TAILQ_REMOVE(&udf_node->vn_bufs, marker, b_vnbufs);
				TAILQ_INSERT_AFTER(&udf_node->vn_bufs, buf_entry, marker, b_vnbufs);

				/* process buf_entry */
				if (buf_entry->b_lblk > last_sector) {
					udf_mark_buf_clean(udf_node, buf_entry);	/* its destroyed so not dirty */
					udf_mark_buf_allocated(udf_node, buf_entry);	/* i.e. taken care of */
					udf_detach_buf_from_node(udf_node, buf_entry);
					udf_free_buf_entry(buf_entry);
				}
				/* trim last buffer entry */
				/* XXX NetBSD kernel : uvm_vnp_zerorange(), vtruncbuf() XXX */
				if (buf_entry->b_lblk == last_sector) {
					buf_entry->b_bcount = udf_node->stat.st_size % lb_size;
					buf_entry->b_resid  = buf_entry->b_bufsize - buf_entry->b_bcount;
					/* still data to record? */
					if (buf_entry->b_bcount == 0) {
						/* marker not an issue here */
						udf_mark_buf_clean(udf_node, buf_entry);	/* its destroyed so not dirty */
						udf_mark_buf_allocated(udf_node, buf_entry);	/* i.e. taken care of */
						udf_detach_buf_from_node(udf_node, buf_entry);
						udf_free_buf_entry(buf_entry);
					}
				}
			}
			TAILQ_REMOVE(&udf_node->vn_bufs, marker, b_vnbufs);
			free(marker);
		UDF_MUTEX_UNLOCK(&udf_node->buf_mutex);
		UDF_MUTEX_UNLOCK(&udf_bufcache->bufcache_lock);

		UDF_MUTEX_LOCK(&udf_node->alloc_mutex);
			if (udf_node->addr_type == UDF_ICB_INTERN_ALLOC) {
				/* shrink intern node */
				too_much = udf_node->stat.st_size - new_extent;
				udf_node->intern_len  -= too_much;
				udf_node->intern_free += too_much;
				memset(udf_node->intern_data + new_extent, 0, too_much);
			} else {
				/* shrink alloc entries _after_ deleting bufs to make sure we are not crossed */
				error = udf_node_release_extent(udf_node, block_extent, udf_node->stat.st_size);

				/* after `cleanup', trim now unused entries */
				udf_merge_allocentry_queue(&udf_node->alloc_entries, lb_size);

				if (new_extent == 0) {
					/* remove all; most common case too */
					while ((alloc_entry = TAILQ_FIRST(&udf_node->alloc_entries))) {
						TAILQ_REMOVE(&udf_node->alloc_entries, alloc_entry, next_alloc);
						free(alloc_entry);
					}
					cur_extent = 0;
				} else {
					/* move code to udf_allocentries.c ? */
					udf_cut_allocentry_queue(&udf_node->alloc_entries, lb_size, block_extent);

					/* find cut-point */
					cur_extent = 0;
					TAILQ_FOREACH(alloc_entry, &udf_node->alloc_entries, next_alloc) {
						cur_extent += alloc_entry->len;
						if (cur_extent == block_extent) break;
					}
					cut_point = alloc_entry;	/* all after this point need to be deleted */

					assert(cut_point);
					while ((alloc_entry = TAILQ_NEXT(cut_point, next_alloc))) {
						TAILQ_REMOVE(&udf_node->alloc_entries, alloc_entry, next_alloc);
						free(alloc_entry);
					}

					/* clip last entry to the correct size */
					if (new_extent < block_extent) {
						assert(too_much == block_extent - new_extent);

						alloc_entry = TAILQ_LAST(&udf_node->alloc_entries, udf_alloc_entries);
						assert(alloc_entry->len > too_much);
		
						alloc_entry->len -= too_much;
						cur_extent -= too_much;
					}
				}
				assert(cur_extent == new_extent);
			}
			udf_node->stat.st_size = new_extent;
		UDF_MUTEX_UNLOCK(&udf_node->alloc_mutex);
	}

	return 0;
}


/* VOP_WRITE */
int udf_write_file_part_uio(struct udf_node *udf_node, char *what, int content, struct uio *data_uio) {
	struct udf_buf  *buf_entry;
	off_t		 offset;
	uint64_t	 new_possible_extent;
	uint64_t	 start_extent, end_extent;
	uint64_t	 lb_size, sector, data_length;
	uint8_t		*base;
	int		 error, appending, allocated;

	if (!udf_node) return EINVAL;

	if (udf_open_logvol(udf_node->udf_log_vol))
		return EROFS;

	/* write chanches both modification and file status times */
	udf_set_timespec_now(&udf_node->stat.st_ctimespec);
	udf_set_timespec_now(&udf_node->stat.st_mtimespec);

	/* Zero length write -> finished */
	if (data_uio->uio_resid == 0) return 0;

	/* TODO lock node directly to avoid multiple writers entering */
/*	pthread_rwlock_wrlock(&udf_node->udf_node_lock); */

	if (!udf_node->dirty) {
		udf_node_mark_dirty(udf_node);
	}

	/* auto-extent file */
	appending = 0;
	allocated = 0;
	new_possible_extent = data_uio->uio_offset + data_uio->uio_resid;
	if (new_possible_extent >= (uint64_t) udf_node->stat.st_size) {
		/* BUGALERT: extra space can be pre-allocated AFTER file length */
		error = udf_truncate_node(udf_node, new_possible_extent);
		appending = 1;
	}

	lb_size = udf_node->udf_log_vol->lb_size;
	while (data_uio->uio_resid) {
		error = 0;
		sector  = data_uio->uio_offset / lb_size;

		/* lookup sector in buffer set */
		UDF_MUTEX_LOCK(&udf_bufcache->bufcache_lock);
			udf_lookup_node_buf(udf_node, sector, &buf_entry);

			if (!buf_entry || (buf_entry && (buf_entry->b_lblk != sector))) {
				/* not found in cache; `page in' sector from file BUT ONLY if we don't completely overwrite it anyway */
				if ((data_uio->uio_resid < lb_size) && (!appending)) {
					DEBUG(printf("Reading in file buffer for %s for %"PRIu64" bytes\n", what, (uint64_t) data_uio->uio_resid));
					error = udf_readin_file_buffer(udf_node, what, sector, content, &buf_entry);
				}

				/* check if the extent is allocated; check assumption that the size of a buffer is a lb_size */
				if (buf_entry)
					assert(buf_entry->b_bufsize == lb_size);
				UDF_MUTEX_LOCK(&udf_node->alloc_mutex);
					start_extent = (uint64_t) lb_size * sector;
					end_extent   = MIN((uint64_t) udf_node->stat.st_size, start_extent + lb_size);
					error = udf_extent_properties(&udf_node->alloc_entries, lb_size, start_extent, end_extent, &allocated);
				UDF_MUTEX_UNLOCK(&udf_node->alloc_mutex);

				/* check free space if space is to allocated */
				if (!buf_entry || !allocated) {
					/* be coulant on metadata here to avoid not to easy to solve resource problems */
					if (content == UDF_C_USERDATA) {
						/* check for space no space anymore for userdata (bit on the safe side really) */
						assert(udf_node->udf_log_vol);
						if (!udf_confirm_freespace(udf_node->udf_log_vol, content, lb_size)) {
							UDF_MUTEX_UNLOCK(&udf_bufcache->bufcache_lock);
							return ENOSPC;
						}
					}
				}
				DEBUG(if (allocated) printf("Writing pre-allocated buffer\n"));

				if (!buf_entry) {
					/* create new buffer */
					error = udf_get_buf_entry(udf_node, &buf_entry);
					if (error) {
						UDF_MUTEX_UNLOCK(&udf_bufcache->bufcache_lock);
						return error;
					}

					/* don't forget to set the relative block number! */
					buf_entry->b_lblk   = sector;
	
					/* add it to the buffer list */
					UDF_MUTEX_LOCK(&udf_node->buf_mutex);
						udf_attach_buf_to_node(udf_node, buf_entry);
					UDF_MUTEX_UNLOCK(&udf_node->buf_mutex);

				}
				assert(buf_entry);

				if (allocated) {
					/*
					 * we could free the old allocated extent and mark it needing allocation
					 * again
					 */
				}
				if (!allocated) {
					/* mark it needs to be allocated, locks are not very nice here */
					UDF_MUTEX_LOCK(&udf_node->buf_mutex);
						udf_mark_buf_needing_allocate(udf_node, buf_entry);
					UDF_MUTEX_UNLOCK(&udf_node->buf_mutex);
				}
			}
			if (error) {
				UDF_MUTEX_UNLOCK(&udf_bufcache->bufcache_lock);
				break; /* while */
			}

			assert(buf_entry);
			offset = data_uio->uio_offset - (off_t) sector*lb_size;
			base   = buf_entry->b_data;

			assert(offset >= 0);
			if (offset >= 0) {
				UDF_MUTEX_LOCK(&udf_node->buf_mutex);
					udf_mark_buf_dirty(udf_node, buf_entry);
	
					data_length = buf_entry->b_bufsize - offset;
					data_length = MIN(data_length, data_uio->uio_resid);
	
					uiomove(base + offset, data_length, data_uio);
	
					buf_entry->b_bcount = MAX(buf_entry->b_bcount, offset + data_length);
					buf_entry->b_resid  = buf_entry->b_bufsize - buf_entry->b_bcount;
				UDF_MUTEX_UNLOCK(&udf_node->buf_mutex);
			}
		UDF_MUTEX_UNLOCK(&udf_bufcache->bufcache_lock);

		if (data_uio->uio_resid == 0) return 0;		/* finished? */
	} /* while */

	return 0;
}


/******************************************************************************************
 *
 * UDF volume and descriptor logic
 *
 ******************************************************************************************/


struct udf_volumeset *udf_search_volumeset(char *volset_id) {
	struct udf_volumeset *volumeset;
	struct udf_pri_vol   *primary;

	/* XXX this is a bit ugly XXX */
	SLIST_FOREACH(volumeset, &udf_volumeset_list, next_volumeset) {
		primary = STAILQ_FIRST(&volumeset->primaries);
		assert(primary->pri_vol);
		if (memcmp(primary->pri_vol->volset_id, volset_id, 128) == 0) return volumeset;
	}
	return NULL;
}


struct udf_pri_vol *udf_search_primary(struct udf_volumeset *set, char *id) {
	struct udf_pri_vol *primary;

	STAILQ_FOREACH(primary, &set->primaries, next_primary) {
		assert(primary->pri_vol);
		if (memcmp(primary->pri_vol->vol_id, id, 32) == 0) return primary;
	}
	return NULL;
}


struct udf_log_vol *udf_search_logical_volume_in_primary(struct udf_pri_vol *primary, char *logvol_id) {
	struct udf_log_vol *here;

	SLIST_FOREACH(here, &primary->log_vols, next_logvol) {
		if (memcmp(here->log_vol->logvol_id, logvol_id, 128) == 0) return here;
	}
	return NULL;
}



/* called not very often ... ; free incomming when not needed */
int udf_proc_pri_vol(struct udf_session *udf_session, struct udf_pri_vol **current, struct pri_vol_desc *incomming) {
	struct udf_volumeset *volset;
	struct udf_pri_vol   *primary;

	assert(current);
	volset = udf_search_volumeset(incomming->volset_id);
	if (!volset) {
		/* create a volume set */
		volset = calloc(1, sizeof(struct udf_volumeset));
		if (!volset) {
			free(incomming);
			return ENOMEM;
		}

		/* populate and link in */
		volset->max_partnum = 0;
		STAILQ_INIT(&volset->primaries);
		SLIST_INSERT_HEAD(&udf_volumeset_list, volset, next_volumeset);
	}
	assert(volset);

	primary = udf_search_primary(volset, incomming->vol_id);
	*current = primary;

	if (!primary) {
		/* create a primary volume */
		primary = calloc(1, sizeof(struct udf_pri_vol));
		if (!primary) {
			free(incomming);
			return ENOMEM;
		}

		/* add to volset's primaries list */
		STAILQ_INSERT_TAIL(&volset->primaries, primary, next_primary);

		*current = primary;
	} else {
		/* mark as current */

		/* ok ... we now need to check if this new descriptor is a newer version */
		if (udf_rw32(incomming->seq_num) <= udf_rw32(primary->pri_vol->seq_num)) {
			if (udf_session->session_num <= (*current)->udf_session->session_num) {
				DEBUG(printf("UDF: DISCARDING primary descriptor for its the same but higher session number\n"));
				/* its an older one; ignore */
				free(incomming);
				return 0;
			}
		}
		DEBUG(printf("UPDATING primary descriptor for it has a higher session number\n"));
	}

	/* update the primary volume descriptor */
	if (primary->pri_vol) free(primary->pri_vol);
	primary->volumeset   = volset;
	primary->pri_vol     = incomming;
	primary->udf_session = udf_session;

	return 0;
}


/* not called often ; free lvid when not used */
int udf_proc_logvol_integrity(struct udf_log_vol *udf_log_vol, struct logvol_int_desc *new_lvid) {
	struct udf_logvol_info *impl;
	uint64_t psize, pfree;
	uint32_t *free_space_pos, *size_pos;
	uint32_t lb_size, part_map;
	uint32_t integrity;
	int error, tagid;

	error = udf_check_tag((union dscrptr *) new_lvid);
	if (error) {
		return error;	/* return error on faulty tag */
	}

	tagid = udf_rw16(new_lvid->tag.id);
	/* getting a terminator tag or zero is an OK condition */
	if ((tagid == TAGID_TERM) || (tagid == 0)) {
		return 0;
	}

	/* not getting an logical volume itegrity volume descriptor is an error now */
	if (tagid != TAGID_LOGVOL_INTEGRITY) {
		printf("IEE! got a %d tag while searching for a logical volume integrity descriptor\n", tagid);
		return EINVAL;	/* XXX error code? XXX */
	}

	/* check CRC on the contents of the logvol integrity */
	error = udf_check_tag_payload((union dscrptr *) new_lvid);
	if (error) {
		return error;
	}

	/* check logvol integrity validity */
	integrity = udf_rw32(new_lvid->integrity_type);
	if ((integrity != UDF_INTEGRITY_OPEN) && (integrity != UDF_INTEGRITY_CLOSED))
		return EINVAL;

	/* allways go for the next in line; silly but thats Ecma-167/UDF */
	/* process information contained in logical volume integrity descriptor */
	udf_log_vol->logvol_state     = integrity;
	udf_log_vol->integrity_serial = udf_rw16(new_lvid->tag.serial_num);
	impl = (struct udf_logvol_info *) (new_lvid->tables + 2*udf_rw32(new_lvid->num_part));

	udf_log_vol->min_udf_readver  = udf_rw16(impl->min_udf_readver);
	udf_log_vol->min_udf_writever = udf_rw16(impl->min_udf_writever);
	udf_log_vol->max_udf_writever = udf_rw16(impl->max_udf_writever);

	udf_log_vol->num_files        = udf_rw32(impl->num_files);
	udf_log_vol->num_directories  = udf_rw32(impl->num_directories);
	udf_log_vol->next_unique_id   = udf_rw64(new_lvid->lvint_next_unique_id);

	/* calculate free space from this integrity descritor */
	lb_size = udf_log_vol->lb_size;

	/* init start positions */
	free_space_pos = &new_lvid->tables[0];
	size_pos       = &new_lvid->tables[udf_log_vol->num_part_mappings];

	/* init counters */
	udf_log_vol->total_space = udf_log_vol->free_space = udf_log_vol->await_alloc_space = 0;
	for (part_map = 0; part_map < udf_log_vol->num_part_mappings; part_map++) {
		psize = udf_rw32(*size_pos); size_pos++;
		pfree = udf_rw32(*free_space_pos); free_space_pos++;
		if (pfree != UINT_MAX) {
			/* if UINT_MAX, its not applicable like virtual space partitions */
			udf_log_vol->total_space += (uint64_t) psize * lb_size;
			udf_log_vol->free_space  += (uint64_t) pfree * lb_size;
		}
	}

	UDF_VERBOSE(
		if (udf_log_vol->logvol_state == UDF_INTEGRITY_OPEN) {
			udf_dump_timestamp("\t\t\t\tmarked open   at ", &new_lvid->time);
		} else {
			udf_dump_timestamp("\t\t\t\tmarked closed at ", &new_lvid->time);
		}
	);
	return 0;
}


void udf_derive_new_logvol_integrity(struct udf_log_vol *udf_log_vol) {
	udf_log_vol->logvol_state     = UDF_INTEGRITY_OPEN;
	udf_log_vol->integrity_serial = 1;

	/* analyse the log vol to check out minimum and maximum read/write versions */
	if (udf_rw16(udf_log_vol->log_vol->tag.descriptor_ver) == 2) {
		udf_log_vol->min_udf_readver  = 0x0102;
		udf_log_vol->min_udf_writever = 0x0150;
		udf_log_vol->max_udf_writever = 0x0150;
	} else {
		udf_log_vol->min_udf_readver  = 0x0201;
		udf_log_vol->min_udf_writever = 0x0201;
		udf_log_vol->max_udf_writever = 0x0201;		/* 2.50? */
	}
	udf_log_vol->num_files       = 0;
	udf_log_vol->num_directories = 0;
	udf_log_vol->next_unique_id  = 16;	/* zero first, rest 15/16+ minimum */
}


int udf_proc_logvol_integrity_sequence(struct udf_log_vol *udf_log_vol) {
	union dscrptr	*dscr;
	uint32_t	 sector, lvid_len, num_sectors;
	uint32_t	 lb_size;
	int		 length;
	int		 error;

	sector  = udf_rw32(udf_log_vol->log_vol->integrity_seq_loc.loc);
	length  = udf_rw32(udf_log_vol->log_vol->integrity_seq_loc.len);
	lb_size = udf_log_vol->lb_size;

	/* go for the default `open' integrity first as initialisation */
	udf_derive_new_logvol_integrity(udf_log_vol);

	if (!length) {
		fprintf(stderr, "UDF: no volume integrity descriptor sequence space defined... OK for Ecma-167, not for UDF; rejecting\n");
		return EBADF;
	}

	error = 0;
	while (length > 0) {
		UDF_VERBOSE_TABLES(
			printf("\t\tLogical volume integrity extent at sector %d for %d bytes\n", sector, length)
		);
		error = udf_read_session_descriptor(udf_log_vol->primary->udf_session, sector, "Logical volume integrity descriptor (LVID)", &dscr, &lvid_len);
		if (error) {
			if (dscr) free(dscr);
			dscr = NULL;
			break;
		}

		UDF_VERBOSE_MAX(udf_dump_descriptor(dscr));

		error = udf_proc_logvol_integrity(udf_log_vol, &dscr->lvid);
		if (error) break;
		if ((udf_rw16(dscr->tag.id) == TAGID_TERM) || (udf_rw16(dscr->tag.id) == 0)) break;

		num_sectors = (lvid_len + lb_size-1) / lb_size;
		length -= num_sectors * lb_size;
		sector += num_sectors;

		if (udf_rw32(dscr->lvid.next_extent.len)) {
			sector = udf_rw32(dscr->lvid.next_extent.loc);
			length = udf_rw32(dscr->lvid.next_extent.len);
		}
		/* free consumed descriptor */
		free(dscr);
		dscr = NULL;
	}
	/* free dangling descriptor */
	if (dscr) free(dscr);

	/* either an error has occured or we have processed all descriptors */
	if (error) {
		fprintf(stderr, "WARNING: integrity sequence ended with a bad descriptor; creating new\n");
		udf_derive_new_logvol_integrity(udf_log_vol);
		return ENOENT;
	}

	/*
	 * If its marked closed we hope/assume all is fine otherwise it may be
	 * marked closed later on when we are using a VAT and its found and
	 * correct
	 */
	return 0;
}


/* Add partition mapping to specified logvol descriptor */
void udf_add_physical_to_logvol(struct logvol_desc *logvol, uint16_t vol_seq_num, uint16_t phys_part_num) {
	union  udf_pmap *pmap;
	uint8_t         *pmap_pos;

	pmap_pos = logvol->maps + udf_rw32(logvol->mt_l);

	pmap = (union udf_pmap *) pmap_pos;
	pmap->pm1.type        = 1;
	pmap->pm1.len         = sizeof(struct part_map_1);
	pmap->pm1.vol_seq_num = udf_rw16(vol_seq_num);
	pmap->pm1.part_num    = udf_rw16(phys_part_num);

	/* increment partition mapping count */
	logvol->n_pm = udf_rw32(udf_rw32(logvol->n_pm) + 1);
	logvol->mt_l = udf_rw32(udf_rw32(logvol->mt_l) + sizeof(struct part_map_1));

	logvol->tag.desc_crc_len = udf_rw16(udf_rw16(logvol->tag.desc_crc_len) + sizeof(struct part_map_1));
}


#if 0
/* not yet */
void udf_add_sparable_to_logvol(struct logvol_desc *logvol, uint16_t vol_seq_num, uint16_t phys_part_num, uint16_t packet_len, ) {
	union  udf_pmap *pmap;
	uint8_t         *pmap_pos;

	pmap_pos = logvol->maps + udf_rw32(logvol->mt_l);

	pmap = (union udf_pmap *) pmap_pos;
	pmap->pm1.type        = 1;
	pmap->pm1.len         = sizeof(struct part_map_1);
	pmap->pm1.vol_seq_num = vol_seq_num;
	pmap->pm1.part_num    = phys_part_num;

	/* increment partition mapping count */
	logvol->n_pm = udf_rw32(udf_rw32(logvol->n_pm) + 1);
	logvol->mt_l = udf_rw32(udf_rw32(logvol->mt_l) + sizeof(struct part_map_1));

	logvol->tag.desc_crc_len = udf_rw16(udf_rw16(logvol->tag.desc_crc_len) + sizeof(struct part_map_1));
}
#endif


/* not called often; free incomming when not needed */
int udf_proc_log_vol(struct udf_pri_vol *primary, struct udf_log_vol **current, struct logvol_desc *incomming) {
	struct udf_log_vol	 *logical;
	struct udf_part_mapping	 *part_mapping, *data_part_mapping, *search_part_mapping;
	union  udf_pmap		 *pmap;
	uint32_t		  part_cnt, pmap_type, pmap_size;
	uint32_t		  data_part_num;
	uint8_t 		 *pmap_pos;

	logical = udf_search_logical_volume_in_primary(primary, incomming->logvol_id);
	if (!logical) {
		/* create a logical volume */
		logical = calloc(1, sizeof(struct udf_log_vol));
		if (!logical) {
			free(incomming);
			return ENOMEM;
		}

		/* link in */
		SLIST_INSERT_HEAD(&primary->log_vols, logical, next_logvol);
	} else {
		/* ok ... we now need to check if this new descriptor is a newer version */
		if (udf_rw32(incomming->seq_num) < udf_rw32(logical->log_vol->seq_num)) {
			/* its an older one; ignore */
			free(incomming);
			return 0;
		}
	}

	/* update the logical volume descriptor and its mappings; first delete old partition mappings allocated before */
	logical->primary  = primary;
	if (current) *current = logical;

	part_mapping = SLIST_FIRST(&logical->part_mappings);
	while ((part_mapping = SLIST_FIRST(&logical->part_mappings))) {
		/* TODO cleanup old cruft ? (XXX while mounted? i don't think so!) */
		/*
			free(part_mapping->sparing_table);
			free(part_mapping->vat_file_entry);
			free(part_mapping->vat);
			free(part_mapping->meta_file);
			free(part_mapping->meta_mirror_file);
			free(part_mapping->meta_bitmap_file);
		*/
		SLIST_REMOVE_HEAD(&logical->part_mappings, next_mapping);
		free(part_mapping);
	}
	SLIST_INIT(&logical->part_mappings);

	/* use the new logical volume and preprocess it */
	if (logical->log_vol) free(logical->log_vol);
	logical->log_vol = incomming;
	logical->lb_size     = udf_rw32(incomming->lb_size);
	logical->sector_size = primary->udf_session->disc->sector_size;

	/* build up the partion mappings */
	logical->num_part_mappings = udf_rw32(incomming->n_pm);

	/* process partition mappings */
	pmap_pos = &logical->log_vol->maps[0];
	for (part_cnt = 0; part_cnt < logical->num_part_mappings; part_cnt++) {
		/* get a new part_mapping structure */
		part_mapping = calloc(1, sizeof(struct udf_part_mapping));
		assert(part_mapping);		/* XXX check with partition mapping destructor etc XXX */

		/*
		 * BUG alert: add to *tail* of list for dependencies sake.
		 * Since this is the only place that its needed, I decided
		 * against changing the SLIST to a TAILQ.
		 */
		if (SLIST_EMPTY(&logical->part_mappings))
			SLIST_INSERT_HEAD(&logical->part_mappings, part_mapping, next_mapping);
		else {
			search_part_mapping = SLIST_FIRST(&logical->part_mappings);
			while (SLIST_NEXT(search_part_mapping, next_mapping))
				search_part_mapping = SLIST_NEXT(search_part_mapping, next_mapping);
			SLIST_INSERT_AFTER(search_part_mapping, part_mapping, next_mapping);
		}

		/* process */
		pmap = (union udf_pmap *) pmap_pos;
		pmap_type = pmap->data[0];
		pmap_size = pmap->data[1];

		part_mapping->udf_virt_part_num = part_cnt;
		part_mapping->udf_pmap = pmap;
		switch (pmap_type) {
			case 1:
				part_mapping->udf_part_mapping_type = UDF_PART_MAPPING_PHYSICAL;
				part_mapping->vol_seq_num = udf_rw16(pmap->pm1.vol_seq_num);
				part_mapping->udf_phys_part_num = udf_rw16(pmap->pm1.part_num);
				break;
			case 2:
				part_mapping->vol_seq_num = udf_rw16(pmap->pm2.vol_seq_num);
				part_mapping->udf_phys_part_num = udf_rw16(pmap->pm2.part_num);
				if (strncmp((char *) pmap->pm2.part_id.id, "*UDF Virtual Partition", UDF_REGID_ID_SIZE) == 0) {
					part_mapping->udf_part_mapping_type = UDF_PART_MAPPING_VIRTUAL;
					break;
				}
				if (strncmp((char *) pmap->pm2.part_id.id, "*UDF Sparable Partition", UDF_REGID_ID_SIZE) == 0) {
					part_mapping->udf_part_mapping_type = UDF_PART_MAPPING_SPARABLE;
					break;
				}
				if (strncmp((char *) pmap->pm2.part_id.id, "*UDF Metadata Partition", UDF_REGID_ID_SIZE) == 0) {
					part_mapping->udf_part_mapping_type = UDF_PART_MAPPING_META;
					break;
				}
				printf("HELP ... found unsupported type 2 partition mapping id `%s`; marking broken\n", pmap->pm2.part_id.id);
			default:
				part_mapping->udf_part_mapping_type = UDF_PART_MAPPING_ERROR;
		}

		pmap_pos += pmap_size;		/* variable length array :( */
	}

	/* flag all partion mappings data and metadata writable */
	SLIST_FOREACH(part_mapping, &logical->part_mappings, next_mapping) {
		part_mapping->data_writable     = 1;
		part_mapping->metadata_writable = 1;
	}

	/* update writable flags depending on mapping type */
	SLIST_FOREACH(part_mapping, &logical->part_mappings, next_mapping) {
		switch (part_mapping->udf_part_mapping_type) {
			case UDF_PART_MAPPING_ERROR :
				part_mapping->data_writable     = 0;
				part_mapping->metadata_writable = 0;
				break;
			case UDF_PART_MAPPING_PHYSICAL :
				break;
			case UDF_PART_MAPPING_VIRTUAL :
			case UDF_PART_MAPPING_META :
				/*
				 * These are special in that there is a special metadata partition where no data
				 * is meant to be written on and vice versa
				 */

				/* find the associated data partition */
				data_part_num     = part_mapping->udf_phys_part_num;
				SLIST_FOREACH(data_part_mapping, &logical->part_mappings, next_mapping) {
					if (data_part_mapping->udf_phys_part_num == data_part_num) {
						if (data_part_mapping != part_mapping) {
							data_part_mapping->metadata_writable = 0;
							break;
						}
					}
				}
				part_mapping->data_writable = 0;
				break;
			case UDF_PART_MAPPING_SPARABLE :
				break;
		}
	}

	TAILQ_INIT(&logical->dirty_nodes);
	UDF_MUTEX_INIT(&logical->dirty_nodes_mutex);

	return 0;
}


/* not called often; free incomming when not needed */
int udf_proc_part(struct udf_pri_vol *primary, struct udf_partition **current, struct part_desc *incomming) {
	struct udf_partition *udf_partition;
	struct udf_volumeset *udf_volset;
	uint32_t new_part_num, sector_size;

	assert(primary);
	assert(primary->pri_vol);

	udf_volset = udf_search_volumeset(primary->pri_vol->volset_id);
	assert(udf_volset);

	new_part_num = udf_rw16(incomming->part_num);
	/* check if its a partition type we recognize */
	if (strncmp((char *) incomming->contents.id, "+NSR0", 5) != 0) {
		fprintf(stderr, "Unrecognized partition content type %s encountered; ignoring\n", incomming->contents.id);
		free(incomming);
		return 0;
	}

	/* look if we allready got it */

	SLIST_FOREACH(udf_partition, &udf_volset->parts, next_partition) {
		if (udf_rw16(udf_partition->partition->part_num) == new_part_num) break;
	}

	/* we have space... now check if this is a newer one than the one known */
	if (udf_partition) {
		if (udf_rw32(incomming->seq_num) < udf_rw32(udf_partition->partition->seq_num)) {
			/* its an older version */
			free(incomming);
			return 0;
		}
	} else {
		/* get us a new udf_partition */
		udf_partition = calloc(1, sizeof(struct udf_partition));
		if (!udf_partition) {
			free(incomming);
			return ENOMEM;
		}

		/* link it in */
		SLIST_INSERT_HEAD(&udf_volset->parts, udf_partition, next_partition);
	}
	assert(udf_partition);

	/* copy this new partition descriptor in the list */
	if (udf_partition->partition) free(udf_partition->partition);
	udf_partition->partition   = incomming;
	udf_partition->udf_session = primary->udf_session;
	udf_volset->max_partnum = MAX(udf_volset->max_partnum, new_part_num+1);	/* REVIEW why +1? */

	/* initialise */
	sector_size = primary->udf_session->disc->sector_size;
	UDF_MUTEX_INIT(&udf_partition->partition_space_mutex);
	TAILQ_INIT(&udf_partition->unalloc_space_queue);
	TAILQ_INIT(&udf_partition->freed_space_queue);
	udf_partition->part_offset = udf_rw32(incomming->start_loc) * sector_size;
	udf_partition->part_length = udf_rw32(incomming->part_len)  * sector_size;
/*	udf_partition->access_type = udf_rw32(incomming->access_type); */

	udf_partition->free_unalloc_space = udf_partition->free_freed_space = 0;

	if (current) *current = udf_partition;

	return 0;
}


/* not called often; free incomming when not needed */
int udf_proc_filesetdesc(struct udf_log_vol *udf_log_vol, struct fileset_desc *incomming) {
	struct udf_mountpoint *mp;

	if (udf_rw16(incomming->tag.id) != TAGID_FSD) {
		printf("IEEE! Encountered a non TAGID_FSD in this fileset descriptor sequence!!!\n");
		free(incomming);
		return EFAULT;
	}

	/* lookup fileset descriptor in this logical volume; interestingly fileset_num is KEY! */
	SLIST_FOREACH(mp, &udf_log_vol->mountpoints, logvol_next) {
		if (mp->fileset_desc->fileset_num == incomming->fileset_num) break;
	}

	if (!mp) {
		/* add a new mountpoint! */
		mp = calloc(1, sizeof(struct udf_mountpoint));
		if (!mp) {
			free(incomming);
			return ENOMEM;
		}
		mp->fileset_desc = incomming;

		/* insert into udf_log_vol and into mountables list */
		SLIST_INSERT_HEAD(&udf_log_vol->mountpoints, mp, logvol_next);
		SLIST_INSERT_HEAD(&udf_mountables, mp, all_next);
	} else {
		/* should we update mountpoint? */
		if (udf_rw32(incomming->fileset_desc_num) <= udf_rw32(mp->fileset_desc->fileset_desc_num)) {
			/* we allready got a newer one */
			free(incomming);
			return 0;
		}

		fprintf(stderr, "UDF DEBUG: would be updating mountpoint... HELP!\n");
		/* FIXME delete all inode hash entries */
		/* XXX how to do that? inodes OK but associated vnodes? XXX */
#if 0
		if (!SLIST_EMPTY(&mp->inodes)) {
			printf("UDF: asked to delete mountpoint with inodes in hashtable!\n");
			printf("Can't cope with that... aborting\n");
			exit(1);
		}
#endif

		/* free old information (allready in lists though!) */
		free(mp->fileset_desc);
		free(mp->mount_name);
	}

	mp->udf_log_vol  = udf_log_vol;
	mp->fileset_desc = incomming;
	mp->mount_name   = strdup(udf_get_compound_name(mp));

	return 0;
}


int udf_retrieve_volume_space(struct udf_discinfo *disc, struct udf_session *udf_session, struct extent_ad *extent) {
	struct udf_pri_vol *udf_pri_vol;
	struct udf_log_vol *udf_log_vol;
	union dscrptr	*dscr;
	uint32_t	 sector, length, dscr_len, num_sectors;
	uint32_t	 sector_size;
	int		 tag_id;
	int		 error;

	udf_pri_vol = NULL;

	sector = udf_rw32(extent->loc);
	length = udf_rw32(extent->len);
	sector_size = disc->sector_size;

	error = 0;	/* XXX zero length area's possible? XXX */
	while (length) {
		error = udf_read_session_descriptor(udf_session, sector, "volume descriptor", &dscr, &dscr_len);
		if (error) {
			if (dscr) free(dscr);
			break;
		}

		tag_id = udf_rw16(dscr->tag.id);
		num_sectors = (dscr_len + sector_size-1) / sector_size;

		/* proc volume descriptor starting at sector `volume_sector' */
		UDF_VERBOSE_MAX(udf_dump_descriptor(dscr));
		switch (tag_id) {
			case TAGID_PRI_VOL       :
				error = udf_proc_pri_vol(udf_session, &udf_pri_vol, &dscr->pvd);
				break;
			case TAGID_PARTITION     :
				error = udf_proc_part(udf_pri_vol, NULL, &dscr->pd);
				break;
			case TAGID_LOGVOL        :
				error = udf_proc_log_vol(udf_pri_vol, &udf_log_vol, &dscr->lvd);
				if (!error) {
					/* first create empty integrity descriptor then modify it on input (for sanity) */
					udf_derive_new_logvol_integrity(udf_log_vol);
				}
				break;
			case TAGID_TERM          :
				free(dscr);
				return 0;	/* terminator */
			case TAGID_UNALLOC_SPACE :
				/* unallocated space descriptor */
				/* Specifies space that is not claimed yet in partitions (!) */
				UDF_VERBOSE(printf("\t\t`unallocated space descriptor' ignored\n"));
				break;
			case TAGID_IMP_VOL       :
				/* implemenation use volume descriptor */
				/* Specifies information relevant for the implementator */
				UDF_VERBOSE_MAX(printf("\t\t`implementation use volume descriptor' ignored\n"));
				break;
			case TAGID_VOL           :
				fprintf(stderr, "UDF : untested volume space extender encountered\n");
				break;
			default :
				printf("XXX Unhandled volume sequence %d; freeing\n", tag_id);
				free(dscr);
				break;
		}

		length -= num_sectors * sector_size;
		sector += num_sectors;

		if (tag_id == TAGID_VOL) {
			sector = udf_rw32(dscr->vdp.next_vds_ex.loc);
			length = udf_rw32(dscr->vdp.next_vds_ex.len);
			free(dscr);
		}
	}

	return error;
}


int udf_get_filelength(union dscrptr *dscr, uint64_t *length) {
	int32_t	fe_tag;

	fe_tag = udf_rw16(dscr->tag.id);
	if (fe_tag == TAGID_FENTRY) {
		*length = udf_rw64(dscr->fe.inf_len);
		return 0;
	} else if (fe_tag == TAGID_EXTFENTRY) {
		*length = udf_rw64(dscr->efe.inf_len);
		return 0;
	}
	return ENOENT;
}


/* can be passed either a file_entry or an extfil_entry trough fentry! */
int udf_check_for_vat(struct udf_log_vol *udf_log_vol, struct udf_part_mapping *part_mapping, uint32_t vat_lb, union dscrptr *dscr) {
	struct udf_part_mapping *s_part_mapping;
	struct udf_node		*vat_udf_node;
	struct long_ad		 udf_icbptr;
	struct regid 		*regid;
	struct uio		 vat_uio;
	struct iovec		 vat_iovec;
	struct icb_tag		*icbtag;
	struct timestamp	*mtime;
	uint64_t		 vat_length, vat_entries;
	uint32_t		*vat_pos, vpart_num;
	uint8_t			*vat;
	int			 error, found;

	/* prepare a `uio' structure for reading in complete VAT file */
	error = udf_get_filelength(dscr, &vat_length);
	if (error) return error;

	if (vat_length == 0)
		return EFAULT;

	vat = malloc(vat_length);
	if (!vat)
		return ENOMEM;

	/* move to uio_newuio(struct uio *uio) with fixed length uio_iovcnt? */
	bzero(&vat_uio, sizeof(struct uio));
	vat_uio.uio_rw     = UIO_WRITE;	/* WRITE into this space */
	vat_uio.uio_iovcnt = 1;
	vat_uio.uio_iov    = &vat_iovec;
	vat_uio.uio_offset = 0;		/* begin at the start */
	vat_uio.uio_resid  = vat_length;
	/* fill in IO vector */
	vat_uio.uio_iov->iov_base = vat;
	vat_uio.uio_iov->iov_len  = vat_length;

	/* find our virtual partition number corresponding to our physical partition number; this sucks */
	found = 0;
	vpart_num = 0;
	SLIST_FOREACH(s_part_mapping, &udf_log_vol->part_mappings, next_mapping) {
		if (s_part_mapping->udf_phys_part_num == part_mapping->udf_phys_part_num) {
			if (s_part_mapping->udf_part_mapping_type == UDF_PART_MAPPING_PHYSICAL) {
				/* found it ! */
				found = 1;
				vpart_num = s_part_mapping->udf_virt_part_num;
			}
		}
	}
	if (!found) {
		printf("Can't find accompanied physical volume\n");
		return ENOENT;
	}

	/* prepare udf_icbptr file node for easy file reading */
	udf_icbptr.loc.part_num	= vpart_num;
	udf_icbptr.loc.lb_num	= udf_rw32(vat_lb);
	udf_icbptr.len		= udf_log_vol->lb_size;	/* not used, but may not be zero */

	/*
	 * this udf_node creation and disposing may look a bit inefficient but
	 * its beneficiary for normal file access.  its only used once for
	 * reading in the VAT.
	 */

	/* create the udf_vat_node; anonymous since it can't be in a mountpoint */
	error = udf_readin_anon_udf_node(udf_log_vol, dscr, &udf_icbptr, "VAT", &vat_udf_node);
	if (!error) {
		DEBUG(printf("READ FILE PART UIO for VAT\n"));
		error = udf_read_file_part_uio(vat_udf_node, "VAT contents", 0, &vat_uio);
		DEBUG(printf("vat_uio rest %d\n", (uint32_t) vat_uio.uio_resid));
	}

	/* XXX allow for SHORT VAT's ? XXX */
	if (!error) {
		if (vat_uio.uio_resid) {
			fprintf(stderr, "Warning: VAT file can't be read in completely\n");
		}

		part_mapping->vat_udf_node = vat_udf_node;
		part_mapping->vat          = (struct udf_vat *) vat;
		part_mapping->vat_length   = vat_length;

		/* extract next unique file ID from the VAT file entry's unique ID incremented by one */
		udf_log_vol->next_unique_id = vat_udf_node->unique_id;	/* ok? */
		udf_increment_unique_id(udf_log_vol);

		/* fentry is confirmed to be either an file_entry or an extfile_entry here */
		if (udf_rw16(dscr->tag.id) == TAGID_FENTRY) {
			icbtag = &dscr->fe.icbtag;
			mtime  = &dscr->fe.mtime;

		} else {
			icbtag = &dscr->efe.icbtag;
			mtime  = &dscr->efe.mtime;
		}

		if (icbtag->file_type == UDF_ICB_FILETYPE_VAT) {
			/* we are in UDF 2.00+ userland */
			part_mapping->vat_translation = ((uint8_t *) part_mapping->vat) + udf_rw16(part_mapping->vat->header_len);
			part_mapping->vat_entries     = (vat_length - udf_rw16(part_mapping->vat->header_len))/4;
			udf_log_vol->num_files        = udf_rw32(part_mapping->vat->num_files);
			udf_log_vol->num_directories  = udf_rw32(part_mapping->vat->num_directories);
			udf_log_vol->min_udf_readver  = udf_rw16(part_mapping->vat->min_udf_readver);
			udf_log_vol->min_udf_writever = udf_rw16(part_mapping->vat->min_udf_writever);
			udf_log_vol->max_udf_writever = udf_rw16(part_mapping->vat->max_udf_writever);

			/* TODO update logvol name */
		} else {
			/* still in the old UDF 1.50 userland; update? its notoriously broken */
			/* check the old UDF 1.50 VAT */
			DEBUG(printf("CHECK UDF 1.50 VAT\n"));
			vat_pos     = (uint32_t *) vat;
			vat_entries = (vat_length-36)/4;	/* definition */

			regid = (struct regid *) (vat_pos + vat_entries);
			error = (strncmp((char *) regid->id, "*UDF Virtual Alloc Tbl", 22) == 0) ? 0 : ENOENT;
			if (!error) {
				part_mapping->vat_entries = vat_entries;
				part_mapping->vat_translation = vat;
				part_mapping->vat = NULL;

				/* num files/dirs? */
			}
		}
		if (!error) {
			UDF_VERBOSE(udf_dump_timestamp("\t\t\t\tmarked closed at ", mtime));
		}
	}

	/* clean up uio structure */
	if (error) {
		if (vat) free(vat);
		if (vat_udf_node) udf_dispose_udf_node(vat_udf_node);
		part_mapping->vat_udf_node = NULL;
	}

	return error;
}


int udf_retrieve_supporting_tables(struct udf_log_vol *udf_log_vol) {
	struct udf_partition	 *udf_partition;
	struct udf_part_mapping	 *part_mapping, *s_part_mapping;
	struct udf_session	 *udf_session;
	struct long_ad		  udf_icbptr;
	union  dscrptr		 *possible_vat_fe;
	union  dscrptr		 *sparing_table_dscr;
	uint32_t		  spar_loc;
	uint64_t		  first_vat_loc, vat_loc, last_vat_loc;
	uint32_t		  sector_size, lb_size;
	uint32_t		  part_num, spar_num, data_part_num, vpart_num;
	int			  session_num;
	int			  error;

	/*
	 * if there are any virtual or sparable partition in this logical
	 * volume, try to find their supporting tables so we can find the rest
	 */
	lb_size     = udf_log_vol->lb_size;
	sector_size = udf_log_vol->sector_size;
	SLIST_FOREACH(part_mapping, &udf_log_vol->part_mappings, next_mapping) {
		part_num = part_mapping->udf_virt_part_num;
		udf_logvol_vpart_to_partition(udf_log_vol, part_num, NULL, &udf_partition);

		UDF_VERBOSE_TABLES(printf("\tFor partition mapping %d->%d\n", part_num, part_mapping->udf_phys_part_num));
		switch (part_mapping->udf_part_mapping_type) {
			case UDF_PART_MAPPING_ERROR    :
				/* nothing to be done for these */
				break;
			case UDF_PART_MAPPING_PHYSICAL :
				/* nothing to be done for these; no supporting tables */
				break;
			case UDF_PART_MAPPING_VIRTUAL  :
				/*
				 * we have to find a good VAT at the END of the session. Since VAT's are
				 * only to be used on WORM's and need to written as last, the strategy is
				 * to go for the predicted end of this session and walk UP
				 */
				udf_session = udf_log_vol->primary->udf_session;
				session_num = udf_session->session_num;

				UDF_VERBOSE_TABLES(printf("\t\tSearching for the VAT :\n"));
				if (udf_session->session_length == 0) {
					UDF_VERBOSE(
						printf("\t\tThis virtual partition is inaccessible since its its size is not known;\n");
						printf("\t\tTry to insert the disc in a CD or DVD recordable device to access it.\n");
					);
					part_mapping->udf_part_mapping_type = UDF_PART_MAPPING_ERROR;
					continue;
				}

				if (udf_session->disc->next_writable[session_num]) {
					last_vat_loc = udf_session->disc->next_writable[session_num];
				} else {
					last_vat_loc = udf_session->disc->session_end[session_num];
				}
				last_vat_loc += udf_session->disc->blockingnr;

				 /* give some extra slack since sizes are not allways given up correctly */
				first_vat_loc = last_vat_loc - 256; /* 8 blocks of 32 */
				first_vat_loc = MAX(first_vat_loc, (uint64_t) udf_session->disc->session_start[session_num]);

				/* try to find the fileid for the VAT; NOTE that we are reading backwards :( */
				vat_loc = last_vat_loc;
				do {
					DEBUG(
						printf("Trying VAT at sector %d in session\n", (int) vat_loc)
					);
					error = udf_read_session_descriptor(udf_session, vat_loc, "VAT file entry", &possible_vat_fe, NULL);
					if (!error) {
						error = udf_check_tag_presence(possible_vat_fe, TAGID_FENTRY);
						if (error)
							error = udf_check_tag_presence(possible_vat_fe, TAGID_EXTFENTRY);
					}
					if (!error) error = udf_check_tag_payload( possible_vat_fe);
					if (!error) error = udf_check_for_vat(udf_log_vol, part_mapping, vat_loc, possible_vat_fe);
					if (!error) {
						break;
					} else {
						if (possible_vat_fe) free(possible_vat_fe);
						vat_loc--;
						if (vat_loc < first_vat_loc) error = EIO;
					}
				} while (error != EIO);

				if (error) {
					printf("WARNING: was looking for a VAT but didnt find it; marking logical volume broken\n");
					part_mapping->udf_part_mapping_type = UDF_PART_MAPPING_ERROR;
					udf_log_vol->logvol_state = UDF_INTEGRITY_OPEN;
					udf_log_vol->broken = 1;
					continue;
				}
				UDF_VERBOSE_TABLES(printf("\t\t\tfound VAT file-entry at device logical sector %d\n", (uint32_t) vat_loc));
				UDF_VERBOSE_TABLES(printf("\t\t\tFound %d byte VAT descriptor+table\n", (uint32_t) part_mapping->vat_length));

				UDF_VERBOSE_TABLES(udf_dump_descriptor(possible_vat_fe));
				UDF_VERBOSE_MAX(udf_dump_vat_table(part_mapping));

				if (part_mapping->vat_translation) {
					/* the presence of a correct VAT means the logical volume is in a closed state */
					udf_log_vol->logvol_state = UDF_INTEGRITY_CLOSED;
					UDF_VERBOSE(printf("\t\t\t\tmarked closed due to presence of VAT\n"));

					/* XXX update `free' space by requesting the device's free space? XXX */
					udf_log_vol->free_space = udf_partition->part_offset + udf_partition->part_length - vat_loc*sector_size;
				}

				if (!udf_session->disc->sequential) {
					UDF_VERBOSE(printf("\t\t\t\tenabling sequential media emulation\n"));
					udf_session->disc->sequential = 1;
				}
				break;
			case UDF_PART_MAPPING_SPARABLE :
				/* we have to find a good sparing table; address are in device logical blocks */
				udf_session = udf_log_vol->primary->udf_session;

				for(spar_num = 0; spar_num < part_mapping->udf_pmap->pms.n_st; spar_num++) {
					spar_loc = udf_rw32(part_mapping->udf_pmap->pms.st_loc[spar_num]);

					/* fetch spar_loc's table ; on THIS session. */
					error = udf_read_session_descriptor(udf_session, spar_loc, "Sparing table", &sparing_table_dscr, NULL);
					if (!error) error = udf_check_tag_presence(sparing_table_dscr, TAGID_SPARING_TABLE);
					if (!error) {
						UDF_VERBOSE_TABLES(printf("\t\tFound the sparing table\n"));
						part_mapping->sparing_table = &sparing_table_dscr->spt;
						break;
					} else {
						if (sparing_table_dscr) free(sparing_table_dscr);
					}
				}
				if (!part_mapping->sparing_table) {
					part_mapping->udf_part_mapping_type = UDF_PART_MAPPING_ERROR;
				}
				UDF_VERBOSE_TABLES(udf_dump_descriptor((union dscrptr *) part_mapping->sparing_table));
				break;
			case UDF_PART_MAPPING_META :
				/*
				 * set up common locator parts; the files are located inside the `part_num' partion where
				 * this partition is a added layer on.
				 */

				/* find the associated data partition */
				data_part_num     = udf_rw16(part_mapping->udf_pmap->pmm.part_num);

				/* find our virtual partition number corresponding to our physical partition number; this sucks */
				vpart_num = data_part_num;
				SLIST_FOREACH(s_part_mapping, &udf_log_vol->part_mappings, next_mapping) {
					if (s_part_mapping->udf_phys_part_num == data_part_num) {
						if (s_part_mapping->udf_part_mapping_type != UDF_PART_MAPPING_META) {
							/* found it ! */
							vpart_num = s_part_mapping->udf_virt_part_num;
							break;
						}
					}
				}
				udf_icbptr.loc.part_num = vpart_num;
				udf_icbptr.len          = lb_size;		/* defined as maximum size */

				UDF_VERBOSE_TABLES(printf("Reading metadata partition filedescriptor\n"));
				udf_icbptr.loc.lb_num   = udf_rw32(part_mapping->udf_pmap->pmm.meta_file_lbn);
				error = udf_readin_anon_udf_node(udf_log_vol, NULL, &udf_icbptr, "Metadata partition file descriptor", &part_mapping->meta_file);
				if (error == 0)
					UDF_VERBOSE_TABLES(udf_dump_descriptor((union dscrptr *) part_mapping->meta_file));

				udf_icbptr.loc.lb_num   = udf_rw32(part_mapping->udf_pmap->pmm.meta_mirror_file_lbn);
				if ((error == 0) && (udf_icbptr.loc.lb_num != (uint32_t) -1)) {
					UDF_VERBOSE_TABLES(printf("Reading metadata partition mirror filedescriptor\n"));
					error = udf_readin_anon_udf_node(udf_log_vol, NULL, &udf_icbptr, "Metadata partition mirror file descriptor", &part_mapping->meta_mirror_file);
					if (error == 0)
						UDF_VERBOSE_TABLES(udf_dump_descriptor((union dscrptr *) part_mapping->meta_mirror_file));
error = 0; /* XXX ignoring error code for now */
				}

				udf_icbptr.loc.lb_num   = udf_rw32(part_mapping->udf_pmap->pmm.meta_bitmap_file_lbn);
				if ((error == 0) && (udf_icbptr.loc.lb_num != (uint32_t) -1)) {
					UDF_VERBOSE_TABLES(printf("Reading metadata partition bitmap filedescriptor\n"));
					error = udf_readin_anon_udf_node(udf_log_vol, NULL, &udf_icbptr, "Metadata partition bitmap file descriptor", &part_mapping->meta_bitmap_file);
					if (error == 0)
						UDF_VERBOSE_TABLES(udf_dump_descriptor((union dscrptr *) part_mapping->meta_bitmap_file));
				}

				/* if something is wrong, then mark it as a broken partition */
				if (error) {
					/* TODO handle read-errors on the meta data and meta data mirror file descriptors. */
					part_mapping->udf_part_mapping_type = UDF_PART_MAPPING_ERROR;
				}
				break;
		}
	}
	UDF_VERBOSE_TABLES(printf("\n"));
	if (udf_log_vol->broken) return EIO;

	return 0;
}


int udf_retrieve_space_tables(struct udf_log_vol *udf_log_vol) {
	struct udf_partition	 *udf_partition;
	struct udf_part_mapping  *part_mapping;
	struct part_hdr_desc	 *part_hdr_desc;
	union  dscrptr		 *dscrptr;
	uint32_t		  sector;
	uint32_t		  lb_size;
	uint64_t		  length;
	int			  vpart_num, ppart_num;
	int			  error;

	lb_size = udf_log_vol->lb_size;
	SLIST_FOREACH(part_mapping, &udf_log_vol->part_mappings, next_mapping) {
		vpart_num = part_mapping->udf_virt_part_num;
		ppart_num = part_mapping->udf_phys_part_num;
		UDF_VERBOSE_TABLES(printf("\tFor partition mapping %d->%d\n", vpart_num, ppart_num));

		if ((part_mapping->udf_part_mapping_type != UDF_PART_MAPPING_PHYSICAL) &&
		    (part_mapping->udf_part_mapping_type != UDF_PART_MAPPING_SPARABLE)) {
			UDF_VERBOSE_TABLES(printf("\t\tDon't know how to load space tables for type %d\n", part_mapping->udf_part_mapping_type));
			continue;
		}

		/* retrieve and process unallocated- and freed-space information for all used partitions of the logvol */
		error = udf_logvol_vpart_to_partition(udf_log_vol, vpart_num, NULL, &udf_partition);
		assert(udf_partition);
		part_hdr_desc = &udf_partition->partition->pd_part_hdr;

		sector   = udf_rw32(part_hdr_desc->unalloc_space_table.lb_num);
		length   = udf_rw32(part_hdr_desc->unalloc_space_table.len);		/* needed? */
		if (length) {
			error = udf_read_logvol_descriptor(udf_log_vol, vpart_num, sector, "Unallocated space table", &dscrptr, NULL);
			UDF_VERBOSE_MAX(printf("\tUnalloced space table\n"));
			UDF_VERBOSE_MAX(udf_dump_descriptor(dscrptr));
			/* udf_process_space_table(&udf_partition->unalloc_space, dscrptr); */
			free(dscrptr);
		}

		sector   = udf_rw32(part_hdr_desc->unalloc_space_bitmap.lb_num);
		length   = udf_rw32(part_hdr_desc->unalloc_space_bitmap.len);
		if (length && (udf_partition->unalloc_space_bitmap == 0)) {
			error = udf_read_logvol_descriptor(udf_log_vol, vpart_num, sector, "Unallocated space bitmap", &dscrptr, NULL);
			if (!error) {
				UDF_VERBOSE_MAX(printf("\tUnalloced space bitmap\n"));
				UDF_VERBOSE_MAX(udf_dump_descriptor(dscrptr));
				udf_read_in_space_bitmap(&udf_partition->unalloc_space_queue, &dscrptr->sbd, lb_size, &udf_partition->free_unalloc_space);
				UDF_VERBOSE_TABLES(printf("\t\tPhysical partition's unallocated space : %"PRIu64"\n", udf_partition->free_unalloc_space));
				udf_partition->unalloc_space_bitmap = &dscrptr->sbd;
			} else {
				printf("While reading in unallocated space bitmap : %s\n", strerror(error));
				udf_partition->unalloc_space_bitmap = NULL;
				/* TODO mark read-only logvol */
			}
		}

		sector    = udf_rw32(part_hdr_desc->freed_space_table.lb_num);
		length    = udf_rw32(part_hdr_desc->freed_space_table.len);
		if (length) {
			error = udf_read_logvol_descriptor(udf_log_vol, vpart_num, sector, "Freed space table", &dscrptr, NULL);
			UDF_VERBOSE_MAX(printf("\tFreed space table\n"));
			UDF_VERBOSE_MAX(udf_dump_descriptor(dscrptr));
			/* udf_process_space_table(&udf_partition->freed_space, dscrptr); */
			free(dscrptr);
		}

		sector    = udf_rw32(part_hdr_desc->freed_space_bitmap.lb_num);
		length    = udf_rw32(part_hdr_desc->freed_space_bitmap.len);
		if (length && (udf_partition->freed_space_bitmap == NULL)) {
			error = udf_read_logvol_descriptor(udf_log_vol, vpart_num, sector, "Freed space bitmap", &dscrptr, NULL);
			if (!error) {
				UDF_VERBOSE_MAX(printf("\tFreed space bitmap\n"));
				UDF_VERBOSE_MAX(udf_dump_descriptor(dscrptr));
				udf_read_in_space_bitmap(&udf_partition->freed_space_queue, &dscrptr->sbd, lb_size, &udf_partition->free_freed_space);
				UDF_VERBOSE_TABLES(printf("\t\tPhysical partition's freed space : %"PRIu64"\n", udf_partition->free_unalloc_space));
				udf_partition->freed_space_bitmap = &dscrptr->sbd;
			} else {
				printf("While reading in freed space bitmap : %s\n", strerror(error));
				udf_partition->freed_space_bitmap = NULL;
				/* TODO mark read-only logvol */
			}
		}
	}
	UDF_VERBOSE_TABLES(printf("\n"));

	return 0;
}


/*
 * Fileset descriptors are on a logical volume's partitions; since virtual
 * partitions are then also possible its OK to use the VAT for redefining the
 * fileset descriptors.
 */
int udf_retrieve_fileset_descriptor(struct udf_log_vol *udf_log_vol) {
	struct udf_mountpoint	*mountable;
	struct long_ad		*fsd_loc;
	struct fileset_desc	*new_fsd;
	struct udf_node		*vnode;
	uint32_t		 part_num, lb_num;
	int32_t			 length;
	int32_t			 error;

	error = 0; /* flag OK */

	fsd_loc   = &udf_log_vol->log_vol->_lvd_use.fsd_loc;
	part_num  = udf_rw16(fsd_loc->loc.part_num);
	lb_num    = udf_rw32(fsd_loc->loc.lb_num);
	length    = udf_rw32(fsd_loc->len);

	while ((length > 0) && !error) {
		UDF_VERBOSE_TABLES(
			printf("\tFileset descriptor extent at sector %d within partion %d for %d bytes\n", lb_num, part_num, length)
		);

		/* only go for ONE fsb at a time */
		error = udf_read_logvol_descriptor(udf_log_vol, part_num, lb_num, "Fileset descriptor", (union dscrptr **) &new_fsd, NULL);
		if (!error) error = udf_check_tag((union dscrptr *) new_fsd);

		/* TODO need a clearer handling unrecorded blocks here */
		if (error || (!new_fsd) || (new_fsd && (udf_rw16(new_fsd->tag.id) == TAGID_TERM))) {
			/* end of sequence */
			UDF_VERBOSE_TABLES(
				printf("\t\t(Terminator) ");
				if (!new_fsd || error) printf("; unrecorded"); else printf("; explicit");
				printf("\n");
			);
			/* clear error to indicate end of sequence and free possible read in descriptor */
			error = 0;
			if (new_fsd) free(new_fsd);
			break;
		}

		UDF_VERBOSE_MAX(udf_dump_descriptor((union dscrptr *) new_fsd));
		udf_proc_filesetdesc(udf_log_vol, new_fsd);

		if (udf_rw32(new_fsd->next_ex.len) == 0) {
			/* next entry */
			lb_num += 1;
			length -= udf_log_vol->lb_size;
		} else {
			/* follow the next extent */
			fsd_loc  = &new_fsd->next_ex;
			part_num = udf_rw16(fsd_loc->loc.part_num);
			lb_num   = udf_rw32(fsd_loc->loc.lb_num);
			length   = udf_rw32(fsd_loc->len);
		}
	}
	UDF_VERBOSE_TABLES(printf("\n"));

	if (error) return error;

	/* if no error occured, create rootdir udf_nodes */
	SLIST_FOREACH(mountable, &udf_log_vol->mountpoints, logvol_next) {
		/* errors are OK */
		udf_readin_anon_udf_node(udf_log_vol, NULL, &mountable->fileset_desc->rootdir_icb,   "Rootdir",   &mountable->rootdir_node);
		udf_readin_anon_udf_node(udf_log_vol, NULL, &mountable->fileset_desc->streamdir_icb, "Streamdir", &mountable->streamdir_node);

		/* keep names the same ? (duplicate code ahead ... ) */
		if (mountable->rootdir_node) {
			vnode = mountable->rootdir_node;

			vnode->mountpoint = mountable;
			vnode->stat.st_uid = vnode->stat.st_gid = UINT_MAX;
			vnode->stat.st_mode = 0777 | S_IFDIR;

			udf_insert_node_in_hash(vnode);
		}
		if (mountable->streamdir_node) {
			vnode = mountable->streamdir_node;

			vnode->mountpoint = mountable;
			vnode->stat.st_uid = vnode->stat.st_gid = UINT_MAX;
			vnode->stat.st_mode = 0777 | S_IFDIR;

			udf_insert_node_in_hash(vnode);
		}
	}

	return 0;
}


int udf_check_writable_filesets(struct udf_log_vol *udf_log_vol, int mnt_flags) {
	struct udf_mountpoint *mp;
	struct udf_part_mapping *udf_part_mapping;
	int writable;

	writable = 1;
	if (mnt_flags & UDF_MNT_RDONLY)
		writable = 0;

	if (mnt_flags & UDF_MNT_FORCE)
		writable = 1;

	if (udf_log_vol->logvol_state == UDF_INTEGRITY_OPEN) {
		if (!(mnt_flags & UDF_MNT_FORCE)) {
			/* we explicitly DISABLE writing */
			/* XXX do we even reach here? XXX */
			if (udf_verbose) {
				printf("\t\t\t\tmounting READ-ONLY due to open integrity\n");
			} else {
				printf("WARNING: mounting logical volume READ-ONLY due to open integrity\n");
			}
			writable = 0;
		} else {
			printf("WARNING: ignoring open integrity\n");
		}
	}

	SLIST_FOREACH(udf_part_mapping, &udf_log_vol->part_mappings, next_mapping) {
		if (udf_part_mapping->udf_part_mapping_type == UDF_PART_MAPPING_META) {
			writable = 0;
			fprintf(stderr, "\t\t\t\t*** marked read-only due to read-only support for Metadata partition ***\n");
		}
	}

	/* follow all mountpoints of this logical volume and set if they are writable */
	SLIST_FOREACH(mp, &udf_log_vol->mountpoints, logvol_next) {
		mp->writable = writable;
	}
	udf_log_vol->writable = writable;

	/* WAS: */
	/* udf_log_vol->primary->udf_session->writable = mark; */
	return 0;
}


/*
 * udf_eliminate_predescessor_volumesets()
 *
 * We are faced with a curious problem : we are to examine the partitions and
 * determine which are successors of eachother.  This is propably most
 * relevant only on WORM media though. We could consider the following rules :
 * 	1) `glue' according to strict UDF level 1 rules ?
 * 	2) use heuristics info i.e. NERO, DirectCD and mkisofs quirks ?
 * 	3) use overlapping partitions to detect relationships ?
 *
 * Using 1 would imply no multi-volume discs and thus glue everything but that
 * could easily be wrong. Selecting by volumeset names is not possible for
 * Nero f.e. just creates random volumeset names every session and uses no
 * volume version information and thus also violates the UDF rules.
 *
 * Using 2 would be tricky; we know a few programs but what if more are
 * developped? We then would be at loss.
 *
 * Using 3 would imply some calculation but is fail-safe in both supporting
 * multiple volumes on one disc (they seperate) and in supporting
 * multi-session WORM media for these will refer to eachother. Offcource NERO
 * could faul this by just extending the zero partion to the whole disc in its
 * ignorance and thus create false overlapping over other independent
 * sessions. This is to be investigated. I don't know how NERO will react on
 * this situation.
 *
 * Propably method 3 would be good to try :
 *
 * Follow the disc and check for all sessions in order to mark the ones with
 * overlapping partitions as `inactive' and keep the latest one active.
 * Sessions with the `local' quirk are seperate allmost by default; should
 * be change the offsets? would not be too difficult but possible.
 */

void udf_eliminate_predescessor_volumesets(struct udf_discinfo *disc) {
	struct udf_volumeset	*anc_vol_set;
	struct udf_volumeset	*sib_vol_set;
	struct pri_vol_desc	*anc_pri_vol;
	struct pri_vol_desc	*sib_pri_vol;
	struct udf_partition	*anc_part;
	struct udf_partition	*sib_part;
	int			 anc_partnum;
	int			 sib_partnum;
	uint32_t		 anc_start, anc_end;
	uint32_t		 sib_start, sib_end;
	uint32_t		 overlap_start, overlap_end;
	uint32_t		 anc_session;
	uint32_t		 sib_session;

	SLIST_FOREACH(anc_vol_set, &udf_volumeset_list, next_volumeset) {
		anc_pri_vol = STAILQ_FIRST(&anc_vol_set->primaries)->pri_vol;
		sib_vol_set = SLIST_NEXT(anc_vol_set, next_volumeset);
		while (sib_vol_set) {
			sib_pri_vol = STAILQ_FIRST(&sib_vol_set->primaries)->pri_vol;
			DEBUG(
				printf("checking volset %s with volset %s\n", anc_pri_vol->volset_id+1, sib_pri_vol->volset_id+1)
			);
			/* compare these two volume sets but only process partitions on _this_ disc */
			SLIST_FOREACH(anc_part, &anc_vol_set->parts, next_partition) {
				if (anc_part->udf_session->disc != disc)  continue;

				anc_session = anc_part->udf_session->session_num;
				anc_start = 0;
#if 0
				if (disc->session_quirks[anc_session] & CD_SESS_QUIRK_SESSION_LOCAL)
					anc_start += disc->session_start[anc_session];
#endif
				anc_start += udf_rw32(anc_part->partition->start_loc);
				anc_end    = anc_start + udf_rw32(anc_part->partition->part_len);

				SLIST_FOREACH(sib_part, &sib_vol_set->parts, next_partition) {
					if (sib_part->udf_session->disc != disc)  continue;

					sib_session = sib_part->udf_session->session_num;
#if 0
					/* can `session local' volumes even be considered part/successor ? */
					if (disc->session_quirks[sib_session] & CD_SESS_QUIRK_SESSION_LOCAL) continue;
#endif
					sib_start = 0;
#if 0
					if (disc->session_quirks[sib_session] & CD_SESS_QUIRK_SESSION_LOCAL)
						sib_start += disc->session_start[sib_session];
#endif
					sib_start += udf_rw32(sib_part->partition->start_loc);
					sib_end    = sib_start + udf_rw32(sib_part->partition->part_len);
DEBUG(
anc_partnum = udf_rw16(anc_part->partition->part_num);
sib_partnum = udf_rw16(sib_part->partition->part_num);
printf("\t\tchecking partition %d with partition %d ([%d-%d] x [%d-%d])\n", anc_partnum, sib_partnum, anc_start, anc_end, sib_start, sib_end)
);
					overlap_start = MAX(sib_start, anc_start);
					overlap_end   = MIN(sib_end,   sib_end);
					if (overlap_start < overlap_end)  {
DEBUG(
printf("\t\t\tOVERLAP!\n")
);
						if (sib_session < anc_session) {
							/* the sibbling is older */
			UDF_VERBOSE_TABLES(
				printf("\tVolume set ");
				udf_dump_id(NULL, 128, anc_pri_vol->vol_id, &anc_pri_vol->desc_charset);
				printf(" is a newer version of volume set ");
				udf_dump_id(NULL, 128, sib_pri_vol->vol_id, &sib_pri_vol->desc_charset);
				printf("\n");
			);
							sib_vol_set->obsolete = 1;
							break;
						}
					} /* overlap */
					if (sib_vol_set->obsolete) break;
				} /* sibling partition */
				if (sib_vol_set->obsolete) break;
			} /* ancestor partition */
			sib_vol_set = SLIST_NEXT(sib_vol_set, next_volumeset);
		} /* sibling volume set */
	} /* ancestor volume set */
}


int udf_add_session_to_discinfo(struct udf_discinfo *disc, int session, struct anchor_vdp *avdp, int error) {
	struct udf_session	*udf_session;

	udf_session = calloc(1, sizeof(struct udf_session));
	assert(udf_session);

	if (!error) {
		memcpy(&udf_session->anchor, avdp, sizeof(struct anchor_vdp));
	}

	udf_session->disc              = disc;
	udf_session->session_num       = session;
	udf_session->session_offset    = 0;
	udf_session->session_length    = disc->session_end[session] - disc->session_start[session];
	disc->session_quirks[session]  = 0;

	/* writable session administration */
	udf_session->writable = 0;		/* default off */
	error = udf_init_session_caches(udf_session);

	if (!error) {
		/* detect quirks */
		/* XXX session local disabled due to wrong heuristic XXX */
#if 0
		if (disc->session_start[session] > 0) {
			if ((udf_session->anchor.main_vds_ex.loc < disc->session_start[session])) {
				disc->session_quirks[session] |= CD_SESS_QUIRK_SESSION_LOCAL;
				udf_session->session_offset = disc->session_start[session];
			}
		}
#endif
	}

	/* add to tail of session list */
	STAILQ_INSERT_TAIL(&disc->sessions, udf_session, next_session);

	disc->num_udf_sessions++;

	/* record status of this volume */
	disc->session_is_UDF[session] = error ? 0 : 1;

	return error;
}


int udf_get_anchors(struct udf_discinfo *disc) {
	uint8_t			*sector;
	union dscrptr		*dscr;
	uint32_t		 session_start, session_end;
	int			 session, error;

	/* Get all anchors */
	STAILQ_INIT(&disc->sessions);

	sector = NULL;
	for (session = 0; session < disc->num_sessions; session++) {
		/* check for anchors ; no volume recognition data ? */
		session_start = disc->session_start[session];
		session_end   = disc->session_end  [session]-1;

		sector = calloc(1, disc->sector_size);
		if (!sector) return ENOMEM;

		dscr = (union dscrptr *) sector;
		error = udf_read_physical_sectors(disc, session_end, 1, "Anchor", sector);
		if (!error) error = udf_check_tag_presence(dscr, TAGID_ANCHOR);
		if (!error) UDF_VERBOSE_TABLES(printf("Accepting anchor at session end (%d)\n", session_end));
		if (error) {
			error = udf_read_physical_sectors(disc, session_end - 256, 1, "Anchor", sector);
			if (!error) error = udf_check_tag_presence(dscr, TAGID_ANCHOR);
			if (!error) UDF_VERBOSE_TABLES(printf("Accepting anchor at session end - 256 (%d)\n", session_end - 256));
			if (error) {
				error = udf_read_physical_sectors(disc, session_start + 256, 1, "Anchor", sector);
				if (!error) error = udf_check_tag_presence(dscr, TAGID_ANCHOR);
				if (!error) UDF_VERBOSE_TABLES(printf("Accepting anchor at session sector 256 (%d)\n", session_start + 256));
				if (error) {
					/* unclosed CD recordable case due to track reservation for iso9660 filesystems */
					error = udf_read_physical_sectors(disc, session_start + 512, 1, "Anchor", sector);
					if (!error) error = udf_check_tag_presence(dscr, TAGID_ANCHOR);
					if (!error) UDF_VERBOSE_TABLES(printf("Accepting anchor at session sector 512 (%d)\n", session_start + 512));
				}
			}
		}

		if (!error) {
			udf_add_session_to_discinfo(disc, session, (struct anchor_vdp *) sector, error);
		} else {
			free(sector);
		}
	}

	return 0;
}


int udf_get_volumeset_space(struct udf_discinfo *disc) {
	struct udf_session *udf_session;
	int one_good_found;
	int error;

	/* Rip all volume spaces */
	one_good_found = 0;
	UDF_VERBOSE(printf("\tretrieving volume space\n"));
	STAILQ_FOREACH(udf_session, &disc->sessions, next_session) {
		UDF_VERBOSE_MAX(printf("Session %d volumes : \n", udf_session->session_num));

		error = udf_retrieve_volume_space(disc, udf_session, &udf_session->anchor.main_vds_ex);
		if (error) {
			printf("\nError retrieving session %d's volume space; prosessing reserve\n", udf_session->session_num);
			error = udf_retrieve_volume_space(disc, udf_session, &udf_session->anchor.reserve_vds_ex);
		}
		if (!error)
			one_good_found = 1;
	}

	return one_good_found ? 0 : ENOENT;
}


int udf_get_logical_volumes_supporting_tables(struct udf_discinfo *disc, int mnt_flags) {
	struct udf_volumeset	*udf_volumeset;
	struct udf_pri_vol	*udf_pri_vol;
	struct udf_log_vol	*udf_log_vol;
	int logvolint_error;
	int one_good_found;
	int error;

	one_good_found = 0;
	SLIST_FOREACH(udf_volumeset, &udf_volumeset_list, next_volumeset) {
		if (!udf_volumeset->obsolete) {
			STAILQ_FOREACH(udf_pri_vol, &udf_volumeset->primaries, next_primary) {
				if (udf_pri_vol->udf_session->disc == disc) {
					SLIST_FOREACH(udf_log_vol, &udf_pri_vol->log_vols, next_logvol) {
						/* retrieving logical volume integrity sequence */
						UDF_VERBOSE(udf_dump_volume_name("\t\tLogical volume ", udf_log_vol));
						UDF_VERBOSE(printf("\t\t\tintegrity\n"));
						logvolint_error = udf_proc_logvol_integrity_sequence(udf_log_vol);

						/* load in supporting tables */
						UDF_VERBOSE(printf("\t\t\tsupporting tables\n"));
						error = udf_retrieve_supporting_tables(udf_log_vol);

						/* if the state is still marked `open', its dirty and we mount read-only for safety */
						if (logvolint_error) {
							printf("\t\t\t*** marked read-only due to logvol integrity error ***\n");
							mnt_flags |= UDF_MNT_RDONLY;
						}
						if (udf_log_vol->logvol_state == UDF_INTEGRITY_OPEN) {
							printf("\t\t\t*** marked read-only due to open logical volume    ***\n");
							mnt_flags |= UDF_MNT_RDONLY;
						}

						/* get fileset descriptors */
						UDF_VERBOSE(printf("\t\t\tfileset(s)\n"));
						if (!error) error = udf_retrieve_fileset_descriptor(udf_log_vol);
	
						/* check if the logical volume is writable */
						UDF_VERBOSE(printf("\t\t\tchecking writable filesets\n"));
						if (!error) error = udf_check_writable_filesets(udf_log_vol, mnt_flags);

						/* load in free/used space tables for writable volsets */
						UDF_VERBOSE(printf("\t\t\tused/freed space tables\n"));
						if (!error) error = udf_retrieve_space_tables(udf_log_vol);

						if (error) {
							udf_log_vol->broken = 1;
						} else {
							one_good_found = 1;
						}
					} /* logical */
				} /* disc */
			} /* primary */
		} /* if */
	} /* volumeset */

	return one_good_found? 0 : ENOENT;
}


/******************************************************************************************
 *
 * Disc sync
 *
 ******************************************************************************************/


void udf_sync_tables_callback(int reason, struct udf_wrcallback *wrcallback, int error, uint8_t *sectordata) {
	/* struct udf_node *udf_node = (struct udf_node *) wrcallback->structure; */

	wrcallback = wrcallback;	/* not used now */
	sectordata = sectordata;

	if (reason == UDF_WRCALLBACK_REASON_PENDING) {
		/* what to do? */
		return;
	}
	if (reason == UDF_WRCALLBACK_REASON_ANULATE) {
		/* what to do? */
		return;
	}
	assert(reason == UDF_WRCALLBACK_REASON_WRITTEN);
	if (error) {
		printf("UDF error: sync tables write errors in syncnode not fixed!\n");
		return;
	}
}


/* TODO space tables are not coupled on a logical volume but on a partition/disc, so call them on that instead of logvol */
int udf_sync_space_tables(struct udf_log_vol *udf_log_vol) {
	struct udf_partition	 *udf_partition;
	struct udf_part_mapping  *part_mapping;
	struct part_hdr_desc	 *part_hdr_desc;
	struct udf_wrcallback	  wr_callback;
	union  dscrptr		 *dscrptr;
	uint64_t		  length;
	uint32_t		  sector;
	uint32_t		  lb_size, part_len;
	uint16_t		  dscr_ver;
	int			  part_num;
	int			  error;

	lb_size = udf_log_vol->lb_size;

	wr_callback.function = udf_sync_tables_callback;
	SLIST_FOREACH(part_mapping, &udf_log_vol->part_mappings, next_mapping) {
		part_num = part_mapping->udf_virt_part_num;
		UDF_VERBOSE_TABLES(printf("\tFor partition mapping %d->%d\n", part_num, part_mapping->udf_phys_part_num));

		/* retrieve and process unallocated- and freed-space information for all used partitions of the logvol */
		error = udf_logvol_vpart_to_partition(udf_log_vol, part_num, NULL, &udf_partition);
		assert(udf_partition);

		part_hdr_desc = &udf_partition->partition->pd_part_hdr;
		// part_start    = udf_rw32(udf_partition->partition->start_loc);
		part_len      = udf_rw32(udf_partition->partition->part_len);
		dscr_ver      = udf_rw16(udf_partition->partition->tag.descriptor_ver);

		sector   = udf_rw32(part_hdr_desc->unalloc_space_table.lb_num);
		length   = udf_rw32(part_hdr_desc->unalloc_space_table.len);		/* needed? */
		if (length) {
			printf("UDF: Can't write space tables yet\n");
#if 0
			error = udf_read_logvol_descriptor(udf_log_vol, part_num, sector, "Unallocated space table", &dscrptr, NULL);
			UDF_VERBOSE_MAX(printf("\tUnalloced space table\n"));
			UDF_VERBOSE_MAX(udf_dump_descriptor(dscrptr));
			//udf_process_space_table(&udf_partition->unalloc_space, dscrptr);
			free(dscrptr);
#endif
		}

		sector   = udf_rw32(part_hdr_desc->unalloc_space_bitmap.lb_num);
		length   = udf_rw32(part_hdr_desc->unalloc_space_bitmap.len);
		/* printf("unalloc dscr at partition sector %d\n", sector); */
		if (length) {
			/* read it in and modify */
			dscrptr = (union dscrptr *) udf_partition->unalloc_space_bitmap;
			if (!dscrptr) {
				printf("Warning: creating empty unallocated space bitmap for partition's is gone\n");
				error = udf_create_empty_space_bitmap(lb_size, dscr_ver, /* num_lbs */ part_len, (struct space_bitmap_desc **) &dscrptr);
				assert(!error);
				assert(udf_calc_tag_malloc_size(dscrptr, lb_size) <= length);
				udf_partition->unalloc_space_bitmap = &dscrptr->sbd;
			}

			udf_sync_space_bitmap(&udf_partition->unalloc_space_queue, &dscrptr->sbd, lb_size);
			UDF_VERBOSE_MAX(printf("\tWriteout unallocated space bitmap\n"));
			UDF_VERBOSE_MAX(udf_validate_tag_and_crc_sums((union dscrptr *) dscrptr); udf_dump_descriptor(dscrptr));
			udf_write_partition_descriptor(udf_partition, sector, "Unallocated space bitmap", dscrptr, &wr_callback);	/* SESSION descriptor!! */
		}

		sector    = udf_rw32(part_hdr_desc->freed_space_table.lb_num);
		length    = udf_rw32(part_hdr_desc->freed_space_table.len);
		if (length) {
			printf("UDF: Can't write space tables yet\n");
#if 0
			error = udf_read_logvol_descriptor(udf_log_vol, part_num, sector, "Freed space table", &dscrptr, NULL);
			UDF_VERBOSE_MAX(printf("\tFreed space table\n"));
			UDF_VERBOSE_MAX(udf_dump_descriptor(dscrptr));
			//udf_process_space_table(&udf_partition->freed_space, dscrptr);
			free(dscrptr);
#endif
		}

		sector    = udf_rw32(part_hdr_desc->freed_space_bitmap.lb_num);
		length    = udf_rw32(part_hdr_desc->freed_space_bitmap.len);
/* printf("freed dscr at partition sector %d\n", sector); */
		if (length) {
			/* read it in and modify */
			dscrptr = (union dscrptr *) udf_partition->freed_space_bitmap;
			if (!dscrptr) {
				printf("Warning: creating empty freed space bitmap for partition's is gone\n");
				error = udf_create_empty_space_bitmap(lb_size, dscr_ver, part_len, (struct space_bitmap_desc **) &dscrptr);
				assert(!error);
				assert(udf_calc_tag_malloc_size(dscrptr, lb_size) <= length);
				udf_partition->freed_space_bitmap = &dscrptr->sbd;
			}

			udf_sync_space_bitmap(&udf_partition->freed_space_queue, &dscrptr->sbd, lb_size);
			UDF_VERBOSE_MAX(printf("\tWriteout freed space bitmap\n"));
			UDF_VERBOSE_MAX(udf_validate_tag_and_crc_sums((union dscrptr *) dscrptr); udf_dump_descriptor(dscrptr));
			udf_write_partition_descriptor(udf_partition, sector, "Freed space bitmap", dscrptr, &wr_callback);	/* SESSION descriptor!! */
		}
	}
	UDF_VERBOSE_TABLES(printf("\n"));

	return 0;
}


int udf_writeout_LVID(struct udf_log_vol *udf_log_vol, int type) {
	union  dscrptr	        *dscr;
	struct logvol_int_desc  *intdesc;
	struct udf_logvol_info  *impl;
	struct udf_session      *session;
	struct udf_partition    *udf_partition;
	struct udf_part_mapping *part_mapping;
	struct desc_tag         *terminator;
	struct udf_wrcallback    wr_callback;
	uint32_t sector, lvid_sector, term_sector;
	uint32_t part_num, *free_space_pos, *size_pos, lb_size;
	uint32_t len, length, lvid_len, num_sectors;
	int error, dscr_ver, tagid;

	/* create a new `fresh' logvol integrity */
	session = udf_log_vol->primary->udf_session;
	lb_size = udf_log_vol->lb_size;
	num_sectors = lb_size / session->disc->sector_size;

	sector  = udf_rw32(udf_log_vol->log_vol->integrity_seq_loc.loc);
	length  = udf_rw32(udf_log_vol->log_vol->integrity_seq_loc.len);

	if (!length)
		return ENOENT;

	intdesc = calloc(1, udf_log_vol->lb_size);
	if (!intdesc)
		return ENOMEM;

	/* search insertion place */
	lvid_sector = 0;
	term_sector = 0;
	while (length) {
		error = udf_read_session_descriptor(udf_log_vol->primary->udf_session, sector, "Logical volume integrity descriptor (LVID)", &dscr, &lvid_len);

		/* getting a terminator tag or zero is an OK condition */
		if (error) {
			tagid = 0;
		} else {
			tagid = udf_rw16(dscr->tag.id);
		}
		if ((tagid == TAGID_TERM) || (tagid == 0)) {
			lvid_sector = sector;
			if (length > lb_size) {
				/* space for a terminator */
				term_sector = sector + num_sectors;
			}
			break;	/* while */
		}
		length -= lb_size;
		sector += num_sectors;

		if (udf_rw32(dscr->lvid.next_extent.len)) {
			sector = udf_rw32(dscr->lvid.next_extent.loc);
			length = udf_rw32(dscr->lvid.next_extent.len);
		}
		/* free consumed descriptor */
		free(dscr);
		dscr = NULL;
	}
	if (dscr) free(dscr);

	if ((!lvid_sector) || (length == 0)) {
		sector  = udf_rw32(udf_log_vol->log_vol->integrity_seq_loc.loc);
		length  = udf_rw32(udf_log_vol->log_vol->integrity_seq_loc.len);
		lvid_sector = sector;
		if (length > lb_size) {
			/* space for a terminator */
			term_sector = lvid_sector + num_sectors;
		}
	}
	assert(lvid_sector);

	/* build up integrity descriptor and write it out */
	dscr_ver = udf_rw16(udf_log_vol->log_vol->tag.descriptor_ver);
	udf_init_desc_tag(&intdesc->tag, TAGID_LOGVOL_INTEGRITY, dscr_ver, udf_log_vol->integrity_serial);

	udf_set_timestamp_now(&intdesc->time);
	intdesc->integrity_type = udf_rw32(type);

	intdesc->lvint_next_unique_id = udf_rw64(udf_log_vol->next_unique_id);

	/* calculate and fill in free space */
	intdesc->num_part = udf_rw32(udf_log_vol->num_part_mappings);
	free_space_pos = &intdesc->tables[0];
	size_pos       = &intdesc->tables[udf_log_vol->num_part_mappings];
	SLIST_FOREACH(part_mapping, &udf_log_vol->part_mappings, next_mapping) {
		part_num = part_mapping->udf_virt_part_num;
		udf_logvol_vpart_to_partition(udf_log_vol, part_num, NULL, &udf_partition);
		assert(udf_partition);

		*size_pos++       = udf_partition->partition->part_len;
		*free_space_pos++ = udf_rw32(udf_partition->free_unalloc_space / udf_log_vol->lb_size);
	}

	/* fill in UDF implementation use parameters */
	impl = (struct udf_logvol_info *) (&intdesc->tables[2*udf_log_vol->num_part_mappings]);
	udf_set_imp_id(&impl->impl_id);
	impl->num_files        = udf_rw32(udf_log_vol->num_files);
	impl->num_directories  = udf_rw32(udf_log_vol->num_directories);
	impl->min_udf_readver  = udf_rw16(udf_log_vol->min_udf_readver);
	impl->min_udf_writever = udf_rw16(udf_log_vol->min_udf_writever);
	impl->max_udf_writever = udf_rw16(udf_log_vol->max_udf_writever);

	intdesc->l_iu = udf_rw32(sizeof(struct udf_logvol_info));		/* ECMA 3/10.10.7, UDF 2.2.6.4. */
	len  = sizeof(struct logvol_int_desc) - sizeof(uint32_t);		/* length of logvol_int_desc without the extra table entry */
	len += sizeof(uint32_t) * 2 * udf_log_vol->num_part_mappings;		/* size and free space */
	len += sizeof(struct udf_logvol_info);					/* extra implementation use area */
	len -= UDF_DESC_TAG_LENGTH;						/* without header */
	intdesc->tag.desc_crc_len = udf_rw16(len);

	udf_write_session_descriptor(session, lvid_sector, "Logvol integrity descriptor (LVID)", (union dscrptr *) intdesc, &wr_callback);
	if (session->disc->rewritable && term_sector) {
		/* only when there is space and its a rewritable media add a terminor */ 
		error = udf_create_empty_terminator_descriptor(lb_size, dscr_ver, &terminator);
		if (!error) {
			udf_write_session_descriptor(session, term_sector, "Logvol integrity sequence descriptor sequence terminator", (union dscrptr *) terminator, &wr_callback);
			free(terminator);
		}
	}

	free(intdesc);

	return 0;
}


/* mark the logical volume `open'; for non-rewritables (CD-R/DVD+R/DVD-R) this is allmost a no-op */
int udf_open_logvol(struct udf_log_vol *udf_log_vol) {
	int error;

	if (!udf_log_vol->writable) {
		udf_dump_volume_name("\nLogical volume marked read only: ", udf_log_vol);
		return EROFS;
	}

	/* will return many times for each write */
	if (udf_log_vol->logvol_state == UDF_INTEGRITY_OPEN)
		return 0;

	/*
	 * Opening and closing logical volumes is derived from the state of
	 * the primaries disc.
	 */
	udf_dump_volume_name("Opening logical volume", udf_log_vol);
	if (!udf_log_vol->primary->udf_session->disc->sequential) {
		error  = udf_writeout_LVID(udf_log_vol, UDF_INTEGRITY_OPEN);
		assert(!error);
		/* sync caches to make sure all is written out */
		udf_sync_caches(udf_log_vol);
		/* FIXME (callback) XXX ought to wait until we get the ALL-OK signal from the writeout-LVID action XXX */
	} else {
		/* sequential recordable; any write just opens it; the descriptor is allready marked open */
	}

	/* mark it open */
	udf_log_vol->logvol_state = UDF_INTEGRITY_OPEN;

	return 0;
}


/* mark the logical volume in a `closed' state; close the integrity when possible for recordables writeout VAT */
int udf_close_logvol(struct udf_log_vol *udf_log_vol) {
	int error;

	if (udf_log_vol->logvol_state == UDF_INTEGRITY_CLOSED) {
		DEBUG(printf("close logvol: integrity allready closed\n"));
		return 0;
	}

	/*
	 * Opening and closing logical volumes is derived from the state of
	 * the primaries disc.
	 */
	udf_dump_volume_name("Closing logical volume", udf_log_vol);
	if (!udf_log_vol->primary->udf_session->disc->sequential) {
		error  = udf_writeout_LVID(udf_log_vol, UDF_INTEGRITY_CLOSED);
		assert(!error);
	} else {
		/* XXX TODO XXX */
		fprintf(stderr, "write out virtual sectors, compile VAT and write out VAT : not implemented\n");
		return EIO;
	}

	/* sync caches to make sure all is written out */
	udf_sync_caches(udf_log_vol);
	/* FIXME (callback) XXX ought to wait until we get the ALL-OK signal from the writeout-LVID action XXX */

	/* mark it closed again */
	udf_log_vol->logvol_state = UDF_INTEGRITY_CLOSED;
	return 0;
}


int udf_sync_logvol(struct udf_log_vol *udf_log_vol) {
	struct udf_node	*udf_node;
	uint32_t num_dirty, count, prnt;
	int error;

	if (!udf_log_vol->writable)
		return 0;

	if (udf_log_vol->logvol_state == UDF_INTEGRITY_CLOSED) {
		DEBUG(printf("close logvol: its closed so no sync nessisary\n"));
		return 0;
	}

	UDF_VERBOSE(udf_dump_volume_name("\tsyncing ", udf_log_vol));

	/* sync all nodes */
	/* XXX syncing logvol sequential due to insertion sort in add node XXX */
	num_dirty = 0;
	TAILQ_FOREACH(udf_node, &udf_log_vol->dirty_nodes, next_dirty) {
		num_dirty++;
	}

	/*
	 * Purge all data out first, this will speed things up later (not
	 * strickly nessissary since syncing a node will wait for all the data
	 * to be written out first anyway
	 */
	count = num_dirty;
	prnt = 0;
	UDF_VERBOSE(printf("\t\tsyncing data\n"));
	TAILQ_FOREACH(udf_node, &udf_log_vol->dirty_nodes, next_dirty) {
		UDF_VERBOSE(printf("\r%8d", count); fflush(stdout));
		udf_sync_udf_node(udf_node, "Sync Logvol");
		count--;
		prnt = 1;
	}
	if (prnt) UDF_VERBOSE(printf("\r                      \r"));

	/*
	 * Purge all nodes out... they ought to have no dirty buffers anymore
	 * but they will write them out if deemed nessisary
	 */
	count = num_dirty;
	prnt = 0;
	UDF_VERBOSE(printf("\t\tsyncing nodes\n"));
	TAILQ_FOREACH(udf_node, &udf_log_vol->dirty_nodes, next_dirty) {
		UDF_VERBOSE(printf("\r%8d", count); fflush(stdout));
		DEBUG(printf("N"); fflush(stdout));
		udf_writeout_udf_node(udf_node, "Sync Logvol");
		count--;
		prnt = 1;
	}
	if (prnt) UDF_VERBOSE(printf("\r                      \r"));

	/* shouldn't be nessisary */
	udf_bufcache->flushall = 1;
	udf_purgethread_kick("Sync Logvol");
	usleep(1);

	if (udf_bufcache->lru_len_dirty_metadata + udf_bufcache->lru_len_dirty_data) {
		printf("Warning: after syncing logvol dirty counts != 0 (%d, %d); please contact author.\n",
				udf_bufcache->lru_len_dirty_metadata, udf_bufcache->lru_len_dirty_data);
	}

	/* sync free and used space tables for writable volsets */
	UDF_VERBOSE(printf("\t\tused/freed space tables\n"));
	error = udf_sync_space_tables(udf_log_vol);

	/* close logical volume */
	udf_close_logvol(udf_log_vol);

	return error;
}


/* convenience routine */
int udf_sync_disc(struct udf_discinfo *disc) {
	struct udf_volumeset	*udf_volumeset;
	struct udf_pri_vol	*udf_pri_vol;
	struct udf_log_vol	*udf_log_vol;

	SLIST_FOREACH(udf_volumeset, &udf_volumeset_list, next_volumeset) {
		if (!udf_volumeset->obsolete) {
			STAILQ_FOREACH(udf_pri_vol, &udf_volumeset->primaries, next_primary) {
				if (udf_pri_vol->udf_session->disc == disc) {
					SLIST_FOREACH(udf_log_vol, &udf_pri_vol->log_vols, next_logvol) {
						udf_sync_logvol(udf_log_vol);
					} /* logical */
				} /* disc */
			} /* primary */
		} /* if */
	} /* volumeset */

	return 0;
}


/******************************************************************************************
 *
 * UDF descriptor buildup and update functions
 *
 ******************************************************************************************/

static void udf_init_desc_tag(struct desc_tag *tag, uint16_t id, uint16_t dscr_ver, uint16_t serial_num) {
	bzero(tag, sizeof(struct desc_tag));
	tag->id			= udf_rw16(id);
	tag->descriptor_ver	= udf_rw16(dscr_ver);
	tag->serial_num		= udf_rw16(serial_num);
	/* the rest gets filled in when we write */
}


static void udf_osta_charset(struct charspec *charspec) {
	bzero(charspec, sizeof(struct charspec));
	charspec->type = 0;
	strcpy((char *) charspec->inf, "OSTA Compressed Unicode");
}


static void udf_encode_osta_id(char *osta_id, uint16_t len, char *text) {
	uint16_t  u16_name[1024];
	uint8_t  *pos;
	uint16_t *pos16;

	bzero(osta_id, len);
	if (!text) return;

	bzero(u16_name, sizeof(uint16_t) * 1023);
	/* convert ascii to 16 bits unicode */
	pos   = (uint8_t *) text;
	pos16 = u16_name;
	while (*pos) {
		*pos16 = *pos;
		pos++; pos16++;
	}
	*pos16 = 0;

	udf_CompressUnicode(len, 8, (unicode_t *) u16_name, (byte *) osta_id);

	/* Ecma 167/7.2.13 states that the length is recorded in the last byte */
	osta_id[len-1] = strlen(text)+1;
}


static void udf_set_app_id(struct regid *regid) {
	bzero(regid, sizeof(struct regid));
	regid->flags	= 0;						/* not dirty and not protected */
	strcpy((char *) regid->id, APP_NAME);
	regid->id_suffix[0] = APP_VERSION_MAIN;
	regid->id_suffix[1] = APP_VERSION_SUB;
}


static void udf_set_imp_id(struct regid *regid) {
	bzero(regid, sizeof(struct regid));
	regid->flags	= 0;						/* not dirty and not protected */
	strcpy((char *) regid->id, IMPL_NAME);
	regid->id_suffix[0] = 4;	/* unix */
	regid->id_suffix[1] = 0;	/* generic */
#if   defined(__ANONYMOUSUDF__)
#elif defined(__NetBSD__)
	regid->id_suffix[1] = 8;	/* NetBSD */
#elif defined(__FreeBSD__)
	regid->id_suffix[1] = 7;	/* FreeBSD */
#elif defined(LINUX)
	regid->id_suffix[1] = 5;	/* Linux */
#endif
}


static void udf_set_entity_id(struct regid *regid, char *name, uint16_t UDF_version) {
	uint16_t *ver;

	bzero(regid, sizeof(struct regid));
	regid->flags    = 0;						/* not dirty and not protected */
	strcpy((char *) regid->id, name);
	ver  = (uint16_t *) regid->id_suffix;
	*ver = udf_rw16(UDF_version);
	regid->id_suffix[2] = 4;	/* unix */
	regid->id_suffix[3] = 0;	/* generic */
#if   defined(__ANONYMOUSUDF__)
#elif defined(__NetBSD__)
	regid->id_suffix[3] = 8;	/* NetBSD */
#elif defined(__FreeBSD__)
	regid->id_suffix[3] = 7;	/* FreeBSD */
#elif defined(LINUX)
	regid->id_suffix[3] = 5;	/* Linux */
#endif
}


void udf_set_contents_id(struct regid *regid, char *content_id) {
	bzero(regid, sizeof(struct regid));
	regid->flags    = 0;
	strcpy((char *) regid->id, content_id);
}


/* XXX creators of empty descriptors could be externalised */

/*
 * result can be further processed using modify functions if demanded and then
 * processed trough udf_proc_pri_vol
 * [ int udf_proc_pri_vol(struct udf_session *udf_session, struct udf_pri_vol **current, struct pri_vol_desc *incomming); ]
 *
 */

int udf_create_empty_primary_volume_descriptor(uint32_t sector_size, uint16_t dscr_ver, uint16_t serial, char *volset_id, char *privol_name, int vds_num, int max_vol_seq, struct pri_vol_desc **dscrptr) {
	struct pri_vol_desc *dscr;

	assert(dscrptr);
	*dscrptr = NULL;

	/* allocate and populate an empty primary volume descriptor */
	dscr = malloc(sector_size);
	if (!dscr) return ENOMEM;
	bzero(dscr, sector_size);

	udf_init_desc_tag(&dscr->tag, TAGID_PRI_VOL, dscr_ver, 1);
	dscr->pvd_num		= udf_rw32(serial);
	udf_encode_osta_id(dscr->vol_id, 32, privol_name);
	dscr->vds_num		= udf_rw16(vds_num);
	dscr->max_vol_seq	= udf_rw16(max_vol_seq);
	if (max_vol_seq > 1) {
		dscr->ichg_lvl		= udf_rw16(3);			/* signal its a single volume intended to be in a set */
		dscr->max_ichg_lvl	= udf_rw16(3);			/* ,, */
		dscr->flags		= udf_rw16(1);			/* signal relevance volumeset id */
	} else {
		dscr->ichg_lvl		= udf_rw16(2);			/* signal its volume intended not to be in a set */
		dscr->max_ichg_lvl	= udf_rw16(2);			/* ,, */
		dscr->flags		= udf_rw16(0);			/* signal relevance volumeset id */
	}

	dscr->charset_list		= udf_rw32(1);			/* only CS0 */
	dscr->max_charset_list		= udf_rw32(1);
	udf_encode_osta_id(dscr->volset_id, 128, volset_id);
	udf_osta_charset(&dscr->desc_charset);
	udf_osta_charset(&dscr->explanatory_charset);
	udf_set_app_id(&dscr->app_id);
	udf_set_imp_id(&dscr->imp_id);
	udf_set_timestamp_now(&dscr->time);

	dscr->tag.desc_crc_len = udf_rw16(sizeof(struct pri_vol_desc) - UDF_DESC_TAG_LENGTH);

	*dscrptr = dscr;
	return 0;
}


int udf_create_empty_partition_descriptor(uint32_t sector_size, uint16_t dscr_ver, uint16_t serial, uint16_t part_num, uint32_t access_type, uint32_t start_loc, uint32_t part_len, uint32_t space_bitmap_size, uint32_t unalloc_space_bitmap, struct part_desc **dscrptr) {
	struct part_desc     *dscr;
	struct part_hdr_desc *part_hdr;

	assert(dscrptr);
	*dscrptr = NULL;

	/* allocate and populate empty partition descriptor */
	dscr = malloc(sector_size);					/* only descriptor, no bitmap! */
	if (!dscr) return ENOMEM;
	bzero(dscr, sector_size);

	udf_init_desc_tag(&dscr->tag, TAGID_PARTITION, dscr_ver, 1);
	dscr->seq_num  = udf_rw32(serial);
	dscr->flags    = udf_rw16(1);					/* bit 0 : space is allocated */
	dscr->part_num = udf_rw16(part_num);

	if (dscr_ver == 2) udf_set_contents_id(&dscr->contents, "+NSR02");
	if (dscr_ver == 3) udf_set_contents_id(&dscr->contents, "+NSR03");
	part_hdr = &dscr->pd_part_hdr;
	part_hdr->unalloc_space_bitmap.len    = udf_rw32(space_bitmap_size);
	part_hdr->unalloc_space_bitmap.lb_num = udf_rw32(unalloc_space_bitmap);

	dscr->access_type = udf_rw32(access_type);
	dscr->start_loc   = udf_rw32(start_loc);
	dscr->part_len    = udf_rw32(part_len);

	udf_set_imp_id(&dscr->imp_id);					/* why is this ignored? */

	dscr->tag.desc_crc_len = udf_rw16(sizeof(struct part_desc) - UDF_DESC_TAG_LENGTH);

	*dscrptr = dscr;
	return 0;
}


int udf_create_empty_unallocated_space_descriptor(uint32_t sector_size, uint16_t dscr_ver, uint16_t serial, struct unalloc_sp_desc **dscrptr) {
	struct unalloc_sp_desc *dscr;

	assert(dscrptr);
	*dscrptr = NULL;

	/* allocate and populate an empty unallocated space descriptor */
	dscr = malloc(sector_size);
	if (!dscr) return ENOMEM;
	bzero(dscr, sector_size);

	udf_init_desc_tag(&dscr->tag, TAGID_UNALLOC_SPACE, dscr_ver, 1);
	dscr->seq_num		= udf_rw32(serial);
	dscr->tag.desc_crc_len	= udf_rw16(sizeof(struct unalloc_sp_desc) - sizeof(struct extent_ad) - UDF_DESC_TAG_LENGTH);

	*dscrptr = dscr;

	return 0;
}


int udf_create_empty_implementation_use_volume_descriptor(uint32_t sector_size, uint16_t dscr_ver, uint16_t serial, char *logvol_name, struct impvol_desc **dscrptr) {
	struct impvol_desc *dscr;
	struct udf_lv_info *lv_info;

	assert(dscrptr);
	*dscrptr = NULL;

	/* allocate and populate an empty implementation use volume descriptor */
	dscr = malloc(sector_size);
	if (!dscr) return ENOMEM;
	bzero(dscr, sector_size);

	udf_init_desc_tag(&dscr->tag, TAGID_IMP_VOL, dscr_ver, 1);
	dscr->seq_num		= udf_rw32(serial);
	udf_set_entity_id(&dscr->impl_id, "*UDF LV Info", 0x102);	/* just pick one; it'll be modifed later */

	lv_info = &dscr->_impl_use.lv_info;
	udf_osta_charset(&lv_info->lvi_charset);
	udf_encode_osta_id(lv_info->logvol_id, 128, logvol_name);
	udf_encode_osta_id(lv_info->lvinfo1, 36, NULL);
	udf_encode_osta_id(lv_info->lvinfo2, 36, NULL);
	udf_encode_osta_id(lv_info->lvinfo3, 36, NULL);
	udf_set_imp_id(&lv_info->impl_id);

	dscr->tag.desc_crc_len	= udf_rw16(sizeof(struct impvol_desc) - UDF_DESC_TAG_LENGTH);

	*dscrptr = dscr;

	return 0;
}


int udf_create_empty_logical_volume_descriptor(uint32_t sector_size, uint16_t dscr_ver, uint16_t serial, char *logvol_name, uint32_t lb_size, uint32_t integrity_start, uint32_t integrity_length, struct logvol_desc **dscrptr) {
	struct logvol_desc *dscr;

	assert(dscrptr);
	*dscrptr = NULL;

	/* allocate and populate an empty logical volume descriptor */
	dscr = malloc(sector_size);
	if (!dscr) return ENOMEM;
	bzero(dscr, sector_size);

	udf_init_desc_tag(&dscr->tag, TAGID_LOGVOL, dscr_ver, 1);
	dscr->seq_num		= udf_rw32(serial);
	udf_osta_charset(&dscr->desc_charset);
	udf_encode_osta_id(dscr->logvol_id, 128, logvol_name);
	dscr->lb_size		= udf_rw32(lb_size);
	udf_set_contents_id(&dscr->domain_id, "*OSTA UDF Compliant");

	/* no fsd yet nor partition mapping */
	udf_set_imp_id(&dscr->imp_id);
	dscr->integrity_seq_loc.loc = udf_rw32(integrity_start);
	dscr->integrity_seq_loc.len = udf_rw32(integrity_length * lb_size);

	dscr->tag.desc_crc_len = udf_rw16(sizeof(struct logvol_desc) - 1 - UDF_DESC_TAG_LENGTH);

	*dscrptr = dscr;
	return 0;
}


int udf_create_empty_space_bitmap(uint32_t sector_size, uint16_t dscr_ver, uint32_t num_lbs, struct space_bitmap_desc **dscrptr) {
	struct space_bitmap_desc *dscr;
	uint64_t bits;
	uint32_t bytes, space_bitmap_size;

	assert(dscrptr);
	*dscrptr = NULL;

	/* reserve space for unallocated space bitmap */
	bits  = num_lbs;
	bytes = (bits + 7)/8;
	space_bitmap_size = (bytes + sizeof(struct space_bitmap_desc)-1);

	/* round space bitmap size to sector size */
	space_bitmap_size = ((space_bitmap_size + sector_size - 1) / sector_size) * sector_size;

	/* allocate and populate an empty space bitmap descriptor */
	dscr = malloc(space_bitmap_size);
	if (!dscr) return ENOMEM;
	bzero(dscr, space_bitmap_size);

	udf_init_desc_tag(&dscr->tag, TAGID_SPACE_BITMAP, dscr_ver, 1);
	/* crc length 8 is recommended, UDF 2.3.1.2, 2.3.8.1, errata DCN-5108 for UDF 2.50 and lower. */
	dscr->tag.desc_crc_len = udf_rw16(8);

	dscr->num_bits  = udf_rw32(bits);
	dscr->num_bytes = udf_rw32(bytes);

	*dscrptr = dscr;
	return 0;
}


/* FIXME: no rootdir setting yet */
/* FIXME: fileset desc. is disc sector size or lb_size ? */
int udf_create_empty_fileset_desc(uint32_t sector_size, uint16_t dscr_ver, uint32_t fileset_num, char *logvol_name, char *fileset_name, struct fileset_desc **dscrptr) {
	struct fileset_desc *dscr;

	assert(dscrptr);
	*dscrptr = NULL;

	/* allocate and populate an empty logical volume descriptor */
	dscr = malloc(sector_size);
	if (!dscr) return ENOMEM;
	bzero(dscr, sector_size);

	udf_init_desc_tag(&dscr->tag, TAGID_FSD, dscr_ver, 1);
	udf_set_timestamp_now(&dscr->time);
	dscr->ichg_lvl         = udf_rw16(3);	/* fixed? */
	dscr->max_ichg_lvl     = udf_rw16(3);	/* fixed? */
	dscr->charset_list     = udf_rw32(1);	/* only CS0 */
	dscr->max_charset_list = udf_rw32(1);	/* only CS0 */
	dscr->fileset_num      = udf_rw32(fileset_num);	/* key for fileset */
	dscr->fileset_desc_num = udf_rw32(0);		/* fileset descriptor number as in copy # */

	udf_osta_charset(&dscr->logvol_id_charset);
	udf_encode_osta_id(dscr->logvol_id, 128, logvol_name);

	udf_osta_charset(&dscr->fileset_charset);
	udf_encode_osta_id(dscr->fileset_id, 32, fileset_name);

	udf_encode_osta_id(dscr->copyright_file_id, 32, NULL);
	udf_encode_osta_id(dscr->abstract_file_id,  32, NULL);

	udf_set_contents_id(&dscr->domain_id, "*OSTA UDF Compliant");

	dscr->tag.desc_crc_len = udf_rw16(sizeof(struct fileset_desc) - UDF_DESC_TAG_LENGTH);

	*dscrptr = dscr;
	return 0;
}


int udf_create_empty_anchor_volume_descriptor(uint32_t sector_size, uint16_t dscr_ver, uint32_t main_vds_loc, uint32_t reserve_vds_loc, uint32_t length, struct anchor_vdp **vdp) {
	assert(vdp);
	assert(main_vds_loc - reserve_vds_loc >= length);

	*vdp = malloc(sector_size);
	if (!*vdp) return ENOMEM;
	bzero(*vdp, sector_size);

	udf_init_desc_tag(&(*vdp)->tag, TAGID_ANCHOR, dscr_ver, 1);
	(*vdp)->main_vds_ex.loc    = udf_rw32(main_vds_loc);
	(*vdp)->main_vds_ex.len    = udf_rw32(length * sector_size);
	(*vdp)->reserve_vds_ex.loc = udf_rw32(reserve_vds_loc);
	(*vdp)->reserve_vds_ex.len = udf_rw32(length * sector_size);

	(*vdp)->tag.desc_crc_len = udf_rw16(512-UDF_DESC_TAG_LENGTH);		/* fixed size in Ecma */
	return 0;
}


int udf_create_empty_terminator_descriptor(uint32_t sector_size, uint16_t dscr_ver, struct desc_tag **tag) {
	assert(tag);

	*tag = malloc(sector_size);
	if (!*tag) return ENOMEM;
	bzero(*tag, sector_size);

	udf_init_desc_tag(*tag, TAGID_TERM, dscr_ver, 1);

	(*tag)->desc_crc_len = udf_rw16(512-UDF_DESC_TAG_LENGTH);		/* fixed size in Ecma */
	return 0;
}


/******************************************************************************************
 *
 * Basic `open' and `close' disc functions
 *
 ******************************************************************************************/


static void udf_process_session_range(struct udf_discinfo *disc, int *enabled, int low, int high) {
	int session;

	if (!disc) return;

	high = MIN(high, disc->num_sessions-1);
	session = low;

	for (session = low; session <= high; session++) {
		enabled[session] = 1;
	}
}


/* range is specified in -3,5,7 or 5-6,8- etc */
static int udf_process_session_range_string(struct udf_discinfo *disc, char *range) {
	struct udf_session *udf_session, *next_udf_session;
	char *pos, *nop;
	int low, high, len, session;
	int enabled[MAX_SESSIONS];

	if (!range) return 0;
	DEBUG(printf("UDF range debugging string '%s'\n", range));

	if (disc) {
		/* disable all */
		for (session = 0; session < disc->num_sessions; session++) {
			enabled[session] = 0;
		}
	}

	/* parse string */
	nop = strdup(range);
	pos = range;
	if (sscanf(pos, "-%u%n%s", &high, &len, nop) >= 1) {
		DEBUG(printf("UDF range match till %d\n", high));
		udf_process_session_range(disc, enabled, 0, high);
		pos += len;
	}
	if (*pos && *pos == ',') pos++;
	while (*pos) {
		if (sscanf(pos, "%u%n%s", &low, &len, nop) >= 1) {
			pos += len;
			if (*pos == '-') {
				pos++;
				if (!*pos) {
					DEBUG(printf("UDF range match from %d\n", low));
					udf_process_session_range(disc, enabled, low, INT_MAX);
					free(nop);
					return 0;
				}
				if (sscanf(pos, "%u%n%s", &high, &len, nop) >= 1) {
					pos += len;
					DEBUG(printf("UDF range match from %d to %d\n", low, high));
					udf_process_session_range(disc, enabled, low, high);
				}
			} else {
				if (!*pos || (*pos == ',')) {
					DEBUG(printf("UDF range match %d\n", low));
					udf_process_session_range(disc, enabled, low, low);
				}
			}
			if (*pos && (*pos != ',')) {
				fprintf(stderr, "UDF range matching : ',' expected at %s\n", pos);
				free(nop);
				return ENOENT;
			}
			pos++;
		} else {
			fprintf(stderr, "UDF range matching : number expected at %s\n", pos);
			free(nop);
			return ENOENT;
		}
	}
	free(nop);

	DEBUG(printf("UDF range matching : all ok till the end\n"));
	if (!disc) return 0;

	udf_session = STAILQ_FIRST(&disc->sessions);
	while (udf_session) {
		next_udf_session = STAILQ_NEXT(udf_session, next_session);
		session = udf_session->session_num;
		if (!enabled[session]) {
			/* remove this session */
			fprintf(stderr, "UDF: disabling UDF session %d on request\n", session);
			STAILQ_REMOVE(&disc->sessions, udf_session, udf_session, next_session);
			free(udf_session);

			disc->session_is_UDF[session] = 0;
		}
		udf_session = next_udf_session;
	}

	return 0;
}


int udf_check_session_range(char *range) {
	return udf_process_session_range_string(NULL, range);
}


void
udf_init(void)
{
	udf_unix_init();
	udf_start_unix_thread();
	dirhash_init();

	SLIST_INIT(&udf_discs_list);
}


int udf_mount_disc(char *devname, char *range, uint32_t sector_size, int mnt_flags, struct udf_discinfo **disc) {
	int discop_flags, error;

	discop_flags = mnt_flags & UDF_MNT_BSWAP ? UDF_DISCOP_BSWAP : 0;
	error = udf_open_disc(devname, discop_flags, disc);
	if ((!error) && sector_size)
		error = udf_discinfo_alter_perception(*disc, sector_size, 0);
	if (error)
		return error;

	error = udf_get_anchors(*disc);
	UDF_VERBOSE(udf_dump_disc_anchors(*disc));

	if (range) {
		UDF_VERBOSE(printf("Selecting UDF sessions '%s' as specified\n", range));
		udf_process_session_range_string(*disc, range);
		UDF_VERBOSE(udf_dump_disc_anchors(*disc));
	}

	/* no UDF partitions so bail out */
	if ((*disc)->num_udf_sessions == 0) return 0;

	UDF_VERBOSE(printf("Start mounting\n"));
	error = udf_get_volumeset_space(*disc);
	if (error) return error;

	UDF_VERBOSE(printf("\teliminating predescessors\n"));
	udf_eliminate_predescessor_volumesets(*disc);

	UDF_VERBOSE_TABLES(udf_dump_alive_sets());

	UDF_VERBOSE(printf("\tretrieving logical volume dependencies %p\n", *disc));
	error = udf_get_logical_volumes_supporting_tables(*disc, mnt_flags);

	UDF_VERBOSE_TABLES(udf_dump_alive_sets());

	/* insert disc in the disc list */
	SLIST_INSERT_HEAD(&udf_discs_list, *disc, next_disc);

	return error;
}


int udf_dismount_disc(struct udf_discinfo *disc) {
	UDF_VERBOSE(printf("Dismounting disc\n"));
	if (!disc->recordable) {
		/* easy way out: it was a read-only system */
		UDF_VERBOSE(printf("\tdismounting readonly disc\n"));
		udf_stop_unix_thread();
		udf_close_disc(disc);
		return 0;
	}

	/* Sync disc before closing it */
	UDF_VERBOSE(printf("\tsyncing disc\n"));
	udf_sync_disc(disc);

	/* wait for the disc to idle */
	UDF_VERBOSE(printf("\twait for syncing disc to idle\n"));
	while (!udf_discinfo_check_disc_ready(disc)) {
		sleep(1);
	}

	/* stop threads and finish writing to it */
	udf_stop_unix_thread();

	UDF_VERBOSE(printf("\tsignal disc its finished with writing\n"));
	udf_discinfo_finish_writing(disc);

	/* wait for the disc to idle again */
	UDF_VERBOSE(printf("\twait for final disc idling\n"));
	while (!udf_discinfo_check_disc_ready(disc)) {
		sleep(1);
	}

	UDF_VERBOSE(printf("\tclose device\n"));
	udf_close_disc(disc);

	return 0;
}


/******************************************************************************************
 *
 * Directory and other conversion UDF logic
 * Move to udf_unix.c / udf_vnops.c one day?
 *
 ******************************************************************************************/

static int udf_translate_icb_filetype_to_dirent_filetype(int udf_filetype) {
	int d_type;

	switch (udf_filetype) {
		case UDF_ICB_FILETYPE_DIRECTORY :
			d_type = DT_DIR;
			break;
		case UDF_ICB_FILETYPE_STREAMDIR :
			d_type = DT_DIR;
			break;
		case UDF_ICB_FILETYPE_FIFO :
			d_type = DT_FIFO;
			break;
		case UDF_ICB_FILETYPE_CHARDEVICE :
			d_type = DT_CHR;
			break;
		case UDF_ICB_FILETYPE_BLOCKDEVICE :
			d_type = DT_BLK;
			break;
		case UDF_ICB_FILETYPE_RANDOMACCESS :
			d_type = DT_REG;
			break;
		case UDF_ICB_FILETYPE_SYMLINK :
			d_type = DT_LNK;
			break;
		case UDF_ICB_FILETYPE_SOCKET :
			d_type = DT_SOCK;
			break;
		default :
			d_type = DT_UNKNOWN;
			break;
	}
	return d_type;
}


/* VOP_GETATTR */
/* allmost NOOP since we remember the stat in the inode */
int udf_getattr(struct udf_node *udf_node, struct stat *stat) {
	*stat = udf_node->stat;

	/* special: updatables */
	stat->st_nlink   = udf_node->link_cnt;
	stat->st_blocks  = (stat->st_size + 512 -1)/512;	/* blocks are hardcoded 512 bytes/sector in stat :-/ */
	return 0;
}


/* VOP_SETATTR */
/* allmost NOOP since we remember the stat in the inode */
/* note VOP_SETATTR can selectively set attrs		*/
int udf_setattr(struct udf_node *udf_node, struct stat *stat) {
	if (!udf_node) return ENOENT;

	if (udf_open_logvol(udf_node->udf_log_vol))
		return EROFS;

	/* FIXME please don't just copy everything ... XXX */
	udf_node->stat = *stat;

	/* not attribute change time */
	udf_set_timespec_now(&udf_node->stat.st_ctimespec);

	udf_node_mark_dirty(udf_node);
	return 0;
}


void udf_resync_fid_stream(uint8_t *buffer, uint32_t *pfid_pos, uint32_t max_fid_pos, int *phas_fids) {
	struct fileid_desc *fid;
	uint32_t fid_pos;
	int has_fids;

	assert(buffer);
	assert(pfid_pos);
	assert(phas_fids);

	has_fids = 0;
	fid_pos  = *pfid_pos;
	while (!has_fids) {
		while (fid_pos <= max_fid_pos) {
			fid = (struct fileid_desc *) (buffer + fid_pos);
			if (udf_rw16(fid->tag.id) == TAGID_FID)
				break;
			/* fid's can only exist 4 bytes aligned */
			fid_pos += 4;
		}
		if (fid_pos > max_fid_pos) {
			/* shouldn't happen ! to prevent chaos, do nothing */
			/* XXX ought to give a warning? XXX */
			has_fids = 0;
			break;
		} else {
			/* check if we found a valid FID */
			fid = (struct fileid_desc *) (buffer + fid_pos);
			has_fids = (udf_check_tag((union dscrptr *) fid) == 0);
			if (has_fids) {
				assert(udf_rw16(fid->tag.id) == TAGID_FID);
				break;
			}
		}
	}
	*pfid_pos  = fid_pos;
	*phas_fids = has_fids;
}


/* read one fid and process it into a dirent and advance to the next */
/* (*fid) has to be allocated a logical block in size, (*dirent) struct dirent length */
int udf_read_fid_stream(struct udf_node *dir_node, uint64_t *offset, struct fileid_desc *fid, struct dirent *dirent) {
	struct uio     dir_uio;
	struct iovec   dir_iovec;
	char          *fid_name;
	uint32_t       entry_length, lb_size;
	int            enough, error;

	assert(fid);
	assert(dirent);
	assert(dir_node);
	assert(offset);
	assert(*offset != 1);

	lb_size = dir_node->udf_log_vol->lb_size;
	entry_length = 0;
	bzero(dirent, sizeof(struct dirent));
	bzero(fid, lb_size);

	if (*offset >= (uint64_t) dir_node->stat.st_size)
		return EINVAL;

	bzero(&dir_uio, sizeof(struct uio));
	dir_uio.uio_rw     = UIO_WRITE;	/* write into this space */
	dir_uio.uio_iovcnt = 1;
	dir_uio.uio_iov    = &dir_iovec;
	dir_iovec.iov_base = fid;
	dir_iovec.iov_len  = lb_size;
	dir_uio.uio_offset = *offset;
	dir_uio.uio_resid  = MIN(dir_node->stat.st_size - (*offset), lb_size);

	error = udf_read_file_part_uio(dir_node, "file id" /* udf_node->dirent.d_name */, UDF_C_FIDS, &dir_uio);
	if (error)
		return error;

	/*
	 * Check if we got a whole descriptor.
	 * XXX Try to `resync' directory stream when something is very wrong.
	 *
	 */
	enough = (dir_uio.uio_offset - (*offset) >= UDF_FID_SIZE);
	if (!enough) {
		/* short dir ... */
		return EIO;
	}

	error = udf_check_tag((union dscrptr *) fid);
	if (!error) {
		entry_length = udf_calc_tag_malloc_size((union dscrptr *) fid, lb_size);
		enough = (dir_uio.uio_offset - (*offset) >= entry_length);
	}
	if (!enough) {
		/* short dir ... */
		return EIO;
	}

	if (!error) error = udf_check_tag_payload((union dscrptr *) fid);
	if (error) {
		printf("BROKEN DIRECTORY ENTRY\n");
#if 0
		// udf_dump_desc(&fid->tag);
		// udf_dump_fileid(fid);
#endif
		/* RESYNC? */
		/* TODO: use udf_resync_fid_stream */
		return EIO;
	}

	/* we got a whole and valid descriptor */
	/* create resulting dirent structure */
	fid_name = (char *) fid->data + udf_rw16(fid->l_iu);
	dirent->d_fileno = udf_rw32(fid->icb.impl.im_used.unique_id);	/* only 32 bits salvageable */
#if !defined(__DragonFly__)
	dirent->d_reclen = sizeof(struct dirent);
#endif
	dirent->d_type   = DT_UNKNOWN;
	udf_to_unix_name(dirent->d_name, fid_name, fid->l_fi, &dir_node->udf_log_vol->log_vol->desc_charset);
#ifndef NO_DIRENT_NAMLEN
	dirent->d_namlen = strlen(dirent->d_name);
#endif

	if (fid->file_char & UDF_FILE_CHAR_DIR) dirent->d_type = DT_DIR;
	if (fid->file_char & UDF_FILE_CHAR_PAR) strcpy(dirent->d_name, "..");

	/* advance */
	*offset += entry_length;

	return error;
}


/* VOP_READDIR */
/* read in dirent's until the result_uio can't hold another */
int udf_readdir(struct udf_node *dir_node, struct uio *result_uio, int *eof_res /* int *cookies, int ncookies */) {
	struct fileid_desc *fid;
	struct dirent  dirent;
	uint64_t diroffset, transoffset;
	uint32_t lb_size;
	int      eof;
	int      error;

	assert(eof_res);
	if (!dir_node)
		return EINVAL;
	if (!dir_node->udf_log_vol)
		return EINVAL;

	assert(result_uio->uio_resid >= sizeof(struct dirent));
	lb_size = dir_node->udf_log_vol->lb_size;

	fid = malloc(lb_size);
	if (!fid) return ENOMEM;

	/* check if we ought to insert dummy `.' node */
	if (result_uio->uio_offset == 0) {
		bzero(&dirent, sizeof(struct dirent));
		strcpy(dirent.d_name, ".");
		dirent.d_type   = DT_DIR;
#ifndef NO_DIRENT_NAMLEN
		dirent.d_namlen = 2;
#endif
		uiomove(&dirent, sizeof(struct dirent), result_uio);

		/* mark with magic value (yeah it suxxs) that we have done the dummy */
		result_uio->uio_offset = 1;
	}

	/* start directory reading */
	diroffset   = result_uio->uio_offset;
	transoffset = diroffset;
	while (diroffset < (uint64_t) dir_node->stat.st_size) {
		/* read just the offset when its flagged */
		if (diroffset == 1) {
			diroffset = result_uio->uio_offset = 0;
		}

		/* read in FIDs */
		error = udf_read_fid_stream(dir_node, &diroffset, fid, &dirent);
		if (error) {
			printf("Error while reading directory file: %s\n", strerror(error));
			free(fid);
			return error;
		}

		/* if there is not enough space for the dirent break off read */
		if (result_uio->uio_resid < sizeof(struct dirent))
			break;

		/* remember the last entry we transfered */
		transoffset = diroffset;

		/* skip deleted entries */
		if (fid->file_char & UDF_FILE_CHAR_DEL)
			continue;

		/* skip not visible entries */
		if (fid->file_char & UDF_FILE_CHAR_VIS)
			continue;

		uiomove(&dirent, sizeof(struct dirent), result_uio);
	}

	/* pass on last transfered offset */
	result_uio->uio_offset = transoffset;

	free(fid);

	eof = (result_uio->uio_offset >= (int64_t) dir_node->stat.st_size);
	if (eof_res) *eof_res = 1;
		*eof_res = eof;

	return 0;
}


static int
dirhash_fill(struct udf_node *dir_node)
{
	struct dirhash *dirh;
	struct fileid_desc *fid;
	struct dirent *dirent;
	uint64_t file_size, pre_diroffset, diroffset;
	uint32_t lb_size;
	int error;

	/* make sure we have a dirhash to work on */
	dirh = dir_node->dir_hash;
	assert(dirh);
	assert(dirh->refcnt > 0);

	if (dirh->flags & DIRH_BROKEN)
		return EIO;
	if (dirh->flags & DIRH_COMPLETE)
		return 0;

	/* make sure we have a clean dirhash to add to */
	dirhash_purge_entries(dirh);

	/* get directory filesize */
	file_size = dir_node->stat.st_size;

	/* allocate temporary space for fid */
	lb_size = dir_node->udf_log_vol->lb_size;
	fid = malloc(lb_size);
	assert(fid);

	/* allocate temporary space for dirent */
	dirent = malloc(sizeof(struct dirent));
	assert(dirent);

	error = 0;
	diroffset = 0;
	while (diroffset < file_size) {
		/* transfer a new fid/dirent */
		pre_diroffset = diroffset;
		error = udf_read_fid_stream(dir_node, &diroffset, fid, dirent);
		if (error) {
			/* TODO what to do? continue but not add? */
			dirh->flags |= DIRH_BROKEN;
			dirhash_purge_entries(dirh);
			break;
		}

		if ((fid->file_char & UDF_FILE_CHAR_DEL)) {
			/* register deleted extent for reuse */
			dirhash_enter_freed(dirh, pre_diroffset,
				udf_fidsize(fid));
		} else {
			/* append to the dirhash */
			dirhash_enter(dirh, dirent, pre_diroffset,
				udf_fidsize(fid), 0);

			/* XXX speedup HACK: preread in our nodes to compensate for too lazy backend */
			{
				struct udf_node *res_node;
				error = udf_readin_udf_node(dir_node, &fid->icb, fid, &res_node);
			}
		}
	}
	dirh->flags |= DIRH_COMPLETE;

	free(fid);
	free(dirent);

	return error;
}


/* XXX yes, move namelen to unsigned int */
int udf_lookup_name_in_dir(struct udf_node *dir_node, char *name, int namelen, struct long_ad *icb_loc, struct fileid_desc *fid, int *found) {
	struct dirhash       *dirh;
	struct dirhash_entry *dirh_ep;
	struct dirent *dirent;
	uint64_t diroffset;
	int hit, error;

	/* set default return */
	*found = 0;

	/* get our dirhash and make sure its read in */
	dirhash_get(&dir_node->dir_hash);
	error = dirhash_fill(dir_node);
	if (error) {
		dirhash_put(dir_node->dir_hash);
		return error;
	}
	dirh = dir_node->dir_hash;

	/* allocate temporary space for dirent */
	dirent  = malloc(sizeof(struct dirent));
	if (!dirent)
		return ENOMEM;

	DEBUG(printf("dirhash_lookup looking for `%*.*s`\n",
		namelen, namelen, name));

	/* search our dirhash hits */
	memset(icb_loc, 0, sizeof(*icb_loc));
	dirh_ep = NULL;
	for (;;) {
		hit = dirhash_lookup(dirh, name, namelen, &dirh_ep);
		/* if no hit, abort the search */
		if (!hit)
			break;

		/* check this hit */
		diroffset = dirh_ep->offset;

		/* transfer a new fid/dirent */
		error = udf_read_fid_stream(dir_node, &diroffset, fid, dirent);
		if (error)
			break;

		DEBUG(printf("dirhash_lookup\tchecking `%*.*s`\n",
			(int) DIRENT_NAMLEN(dirent),  (int) DIRENT_NAMLEN(dirent), dirent->d_name));

		/* see if its our entry */
		assert(DIRENT_NAMLEN(dirent) == (unsigned int) namelen);
		if (strncmp(dirent->d_name, name, namelen) == 0) {
			*found = 1;
			*icb_loc = fid->icb;
			break;
		}
	}
	free(dirent);

	dirhash_put(dir_node->dir_hash);

	return error;
}


static int udf_count_direntries(struct udf_node *dir_node, int count_dotdot, uint32_t *dir_entries) {
	struct fileid_desc *fid;
	struct dirent  dirent;
	uint64_t pos;
	uint32_t lb_size;
	int      eof;
	int      error;

	if (!dir_node) return EINVAL;
	lb_size = dir_node->udf_log_vol->lb_size;

	/* count all directory entries with optional the dotdot too */
	/* only defined in directories XXX DT_COMP also possible XXX */
	if ((dir_node->stat.st_mode & S_IFDIR) == 0)
		return ENOTDIR;

	/* get space to read fid in */
	fid = malloc(lb_size);
	if (!fid) return ENOMEM;

	/* start directory reading */
	*dir_entries = 0;
	pos = 0;

	eof = (pos == (uint64_t) dir_node->stat.st_size);
	while (!eof) {
		/* read in FIDs */
		error = udf_read_fid_stream(dir_node, &pos, fid, &dirent);
		if (error) {
			printf("Error while counting directory entries : %s\n", strerror(error));
			free(fid);
			return error;
		}

		/* process this FID/dirent */
		if ((fid->file_char & UDF_FILE_CHAR_DEL) == 0) {
			if (fid->file_char & UDF_FILE_CHAR_PAR) {
				if (count_dotdot) *dir_entries = *dir_entries + 1;
			} else {
				*dir_entries = *dir_entries + 1;
			}
		}
		/* pos is automatically advanced */
		eof = (pos == (uint64_t) dir_node->stat.st_size);
	}
	/* end of directory */
	free(fid);

	return 0;
}


static int udf_writeout_fid_info(struct udf_node *dir_node, struct fileid_desc *fid, uint64_t offset, uint16_t fid_len) {
	struct uio     uio;
	struct iovec   iovec;
	int flags;

	bzero(&uio, sizeof(struct uio));
	uio.uio_rw     = UIO_READ;	/* read from this space */
	uio.uio_iovcnt = 1;
	uio.uio_iov    = &iovec;
	iovec.iov_base = fid;
	iovec.iov_len  = fid_len;
	uio.uio_offset = offset;
	uio.uio_resid  = fid_len;

	flags = UDF_C_FIDS;
	return udf_write_file_part_uio(dir_node, "file id.", flags, &uio);
}


/* search for a space to record the fid in, not checking if it is allready in it ! */
/* ALERT: not to be used to update a fid ... use writeout_fid_info for that        */
/* ONLY used by udf_create_directory_entry */
static int udf_insert_fid_info(struct udf_node *dir_node, struct udf_node *udf_node, struct fileid_desc *i_fid, uint16_t fidsize) {
	struct dirhash       *dirh;
	struct dirhash_entry *dirh_ep;
	struct fileid_desc   *fid;
	struct dirent dirent;
	uint64_t dir_size, fid_pos, chosen_fid_pos, end_fid_pos;
	uint32_t this_fidsize, chosen_size;
	uint32_t lb_size, lb_rest;
	uint32_t  size_diff, chosen_size_diff;
	char    *fid_name;
	int      descr_ver, hit, error;

	udf_node = udf_node;	/* passed only for printing diagnostic info if required */

	if (!dir_node)
		return EINVAL;

	/* only defined in directories XXX DT_COMP also possible XXX */
	if ((dir_node->stat.st_mode & S_IFDIR) == 0)
		return ENOTDIR;

	/* needs to be 4 bytes aligned to be legal! if not, something is seriously wrong so abort */
	assert((fidsize & 3) == 0);

	/* get our dirhash and make sure its read in */
	dirhash_get(&dir_node->dir_hash);
	error = dirhash_fill(dir_node);
	if (error) {
		dirhash_put(dir_node->dir_hash);
		return error;
	}
	dirh = dir_node->dir_hash;

	/* get info */
	lb_size   = dir_node->udf_log_vol->lb_size;
	dir_size  = dir_node->stat.st_size;
	descr_ver = udf_rw16(dir_node->udf_log_vol->log_vol->tag.descriptor_ver);

	/* get space to read fid in */
	fid = malloc(lb_size);
	if (!fid)
		return ENOMEM;

	/* find position that will fit the FID */
	chosen_fid_pos   = dir_size;
	chosen_size      = 0;
	chosen_size_diff = UINT_MAX;

	/* shut up gcc */
#ifndef NO_DIRENT_NAMLEN
	dirent.d_namlen = 0;
#endif

	/* search our dirhash hits */
	error = 0;
	dirh_ep = NULL;
	for (;;) {
		hit = dirhash_lookup_freed(dirh, fidsize, &dirh_ep);
		/* if no hit, abort the search */
		if (!hit)
			break;

		/* check this hit for size */
		this_fidsize = dirh_ep->entry_size;

		/* check this hit */
		fid_pos     = dirh_ep->offset;
		end_fid_pos = fid_pos + this_fidsize;
		size_diff   = this_fidsize - fidsize;
		lb_rest = lb_size - (end_fid_pos % lb_size);

		/* select if not splitting the tag and its smaller */
		if ((size_diff <= chosen_size_diff) &&
			(lb_rest >= sizeof(struct desc_tag)))
		{
			/* UDF 2.3.4.2+3 specifies rules for iu size */
			if ((size_diff == 0) || (size_diff >= 32)) {
				chosen_fid_pos   = fid_pos;
				chosen_size      = this_fidsize;
				chosen_size_diff = size_diff;
			}
		}
	}

	/* extend directory if no other candidate found */
	if (chosen_size == 0) {
		chosen_fid_pos   = dir_size;
		chosen_size      = fidsize;

		/* special case UDF 2.00+ 2.3.4.4, no splitting up fid tag */
		if (dir_node->addr_type == UDF_ICB_INTERN_ALLOC) {
			/* pre-grow directory to see if we're to switch */
			// udf_grow_node(dir_node, dir_size + chosen_size);
			error = udf_truncate_node(dir_node, chosen_fid_pos + chosen_size);
			assert(!error);
		}

		/* make sure the next fid desc_tag won't be splitted */
		if (dir_node->addr_type != UDF_ICB_INTERN_ALLOC) {
			end_fid_pos = chosen_fid_pos + chosen_size;
			lb_rest = lb_size - (end_fid_pos % lb_size);

			/* pad with implementation use regid if needed */
			if (lb_rest < sizeof(struct desc_tag))
				chosen_size += 32;
		}
	}
	chosen_size_diff = chosen_size - fidsize;

	/* populate the FID */
	memset(fid, 0, lb_size);
	udf_init_desc_tag(&fid->tag, TAGID_FID, descr_ver, 1);		/* tag serial number    */
	fid->file_version_num    = i_fid->file_version_num;
	fid->file_char           = i_fid->file_char;
	fid->icb                 = i_fid->icb; 
	fid->l_iu                = udf_rw16(0);

	if (chosen_size > fidsize) {
		/* insert implementation-use regid to space it correctly */
		fid->l_iu = udf_rw16(chosen_size_diff);

		/* set implementation use */
		udf_set_imp_id((struct regid *) fid->data);
	}

	/* copy name */
	fid->l_fi = i_fid->l_fi;
	memcpy(fid->data + udf_rw16(fid->l_iu), i_fid->data, fid->l_fi); 

	fid->tag.desc_crc_len = chosen_size - UDF_DESC_TAG_LENGTH;

	/* writeout modified piece */
	udf_validate_tag_and_crc_sums((union dscrptr *) fid);
	error = udf_writeout_fid_info(dir_node, fid, chosen_fid_pos, chosen_size);
	assert(!error);

	/* append to the dirhash */
	fid_name = (char *) fid->data + udf_rw16(fid->l_iu);
	dirent.d_fileno = udf_rw32(fid->icb.impl.im_used.unique_id);	/* only 32 bits salvageable */
#if !defined(__DragonFly__)
	dirent.d_reclen = sizeof(struct dirent);
#endif
	dirent.d_type   = DT_UNKNOWN;
	udf_to_unix_name(dirent.d_name, fid_name, fid->l_fi, &dir_node->udf_log_vol->log_vol->desc_charset);
#ifndef NO_DIRENT_NAMLEN
	dirent.d_namlen = strlen(dirent.d_name);
#endif

	if (fid->file_char & UDF_FILE_CHAR_DIR) dirent.d_type = DT_DIR;
	if (fid->file_char & UDF_FILE_CHAR_PAR) strcpy(dirent.d_name, "..");

	dirhash_enter(dirh, &dirent, chosen_fid_pos, udf_fidsize(fid), 1);

	free(fid);
	dirhash_put(dir_node->dir_hash);

	return error;
}


/* create a file in the given directory with the given name and attributes using udf's file_char and udf'd filetype */
/* note
 * 1) that with `refering' node specified its effectively `link()'
 * 2) that with `refering' node specified, `filetype' is discarded as it ought to be the same as the `refering' one
 *
 * XXX this function needs to be splitted into node creation and directory
 * attachment; its now doing both in one go.
 */
int udf_create_directory_entry(struct udf_node *dir_node, char *name, int filetype, int filechar, struct udf_node *refering, struct stat *stat, struct udf_node **new_node) {
	struct udf_allocentry *alloc_entry;
	struct udf_log_vol    *udf_log_vol;
	struct udf_node       *udf_node;
	struct charspec        osta_charspec;
	struct fileid_desc    *fid;
	struct long_ad         icb_loc;
	uint32_t     lb_num, lb_size;
	uint16_t     vpart_num, descr_ver, len;
	int          found, error;

	assert(dir_node);
	assert(name);
	assert(dir_node->udf_log_vol);
	udf_log_vol = dir_node->udf_log_vol;
	lb_size     = udf_log_vol->lb_size;
	descr_ver   = udf_rw16(udf_log_vol->log_vol->tag.descriptor_ver);

	*new_node = NULL;

	/* lookup if it allready exists (sanity mainly) */
	fid = malloc(lb_size);
	assert(fid);

	error = udf_lookup_name_in_dir(dir_node, name, strlen(name), &icb_loc, fid, &found);
	if (!error && found) {
		/* it existed! allready there */
		free(fid);
		return EEXIST;
	}

	if (!refering) {
		/*
		 * Get ourselves an empty node and space to record file
		 * descriptor in.
		 */
		error = udf_init_udf_node(dir_node->mountpoint, udf_log_vol, "New direntry", &udf_node);
		if (error) {
			free(fid);
			return error;
		}

		udf_node->udf_filetype = filetype;
		udf_node->udf_filechar = filechar;
		udf_node->unique_id = udf_increment_unique_id(udf_log_vol);

		/* snif */
		error = udf_allocate_udf_node_on_disc(udf_node);
		if (error) {
			assert(udf_node != dir_node);
			udf_dispose_udf_node(udf_node);
			free(fid);
			return error;
		}

		udf_node->stat = *stat;
		/* note passed creation times; do sanitise them */
#ifndef NO_STAT_BIRTHTIME
		if (udf_insanetimespec(&stat->st_birthtimespec))
			udf_set_timespec_now(&udf_node->stat.st_birthtimespec);
#endif
		if (udf_insanetimespec(&stat->st_ctimespec))
			udf_set_timespec_now(&udf_node->stat.st_ctimespec);
		if (udf_insanetimespec(&stat->st_atimespec))
			udf_set_timespec_now(&udf_node->stat.st_atimespec);
		if (udf_insanetimespec(&stat->st_mtimespec))
			udf_set_timespec_now(&udf_node->stat.st_mtimespec);
	} else {
		/* refering->ignore passed stat info */
		udf_node = refering;
		filetype = udf_node->udf_filetype;

		/* linking changes metadata modification */
		udf_set_timespec_now(&udf_node->stat.st_ctimespec);
	}
	alloc_entry = TAILQ_FIRST(&udf_node->dscr_allocs);
	vpart_num   = alloc_entry->vpart_num;
	lb_num      = alloc_entry->lb_num;

	/* build up new directory entry */
	memset(fid, 0, lb_size);
	udf_osta_charset(&osta_charspec);
	udf_init_desc_tag(&fid->tag, TAGID_FID, descr_ver, 1);		/* tag serial number    */

	if (filechar & UDF_FILE_CHAR_PAR) {
		/* parent or `..' is not allowed to have a name length ... wierd but ok */
		fid->l_fi = 0;
	} else {
		unix_to_udf_name((char *) fid->data, name, &fid->l_fi, &osta_charspec);
	}
	fid->file_version_num = udf_rw16(1);					/* new file/dir; version starts at 1 */
	fid->file_char        = filechar;					/* what is it                        */
	fid->l_iu             = udf_rw32(0);					/* no impl. use                      */
	fid->icb.len          = udf_rw32(lb_size);				/* fill in location                  */
	fid->icb.loc.part_num = udf_rw16(vpart_num);
	fid->icb.loc.lb_num   = udf_rw32(lb_num);

	/* fill in lower 32 bits of unique ID (UDF 3/3.2.2.1) in the impl use part of the FID's long_ad */
	fid->icb.impl.im_used.unique_id = udf_rw32(((udf_node->unique_id << 32) >> 32));

	/* calculate minimum size needed for directory entry */
	len = UDF_FID_SIZE + fid->l_fi;
	len = (len + 3) & ~3;
	fid->tag.desc_crc_len = udf_rw16(len - UDF_DESC_TAG_LENGTH);

	error = udf_insert_fid_info(dir_node, udf_node, fid, len);
	free(fid);	/* Ahum... easily forgotten here */

	if (error) {
		fprintf(stderr, "UDF: fid insertion failed : %s\n", strerror(error));
		if (!refering)
			udf_dispose_udf_node(udf_node);
		return error;
	}

	if (udf_node) {
		/* only insert file in hashlist if its not an explicit reference */
		if (!refering) {
			udf_insert_node_in_hash(udf_node);
		} else {
			refering->link_cnt++;
			udf_node_mark_dirty(refering);
		}
		udf_node_mark_dirty(udf_node);
	}

	*new_node = udf_node;
	return error;
}


/*
 * Rename file from old_name to new_name. `present' is the file to be replaced
 * if found present allready.  Care should be taken that the directory tree is
 * kept intact. To prevent this no path should be possible from the new parent
 * to the node to be renamed if it considers a directory and the new_parent is
 * not equal to the old parent.
 */
/* 
 * VOP_RENAME(struct vnode *fdvp, struct vnode *vp,
 *     struct componentname *fcnp, struct componentname *tdvp,
 *     struct vnode *tvp, struct componentname *tcnp
 *     );
 */
int udf_rename(struct udf_node *old_parent, struct udf_node *rename_me, char *old_name, struct udf_node *new_parent, struct udf_node *present, char *new_name) {
	struct udf_node *new_node;
	int error;

	/* sanity */
	if (!old_parent) return ENOENT;
	if (!new_parent) return ENOENT;
	if (!rename_me)  return ENOENT;
	if (!(old_parent->stat.st_mode & S_IFDIR)) return ENOTDIR;
	if (!(new_parent->stat.st_mode & S_IFDIR)) return ENOTDIR;

	if (udf_open_logvol(old_parent->udf_log_vol))
		return EROFS;

	if (udf_open_logvol(new_parent->udf_log_vol))
		return EROFS;

	if ((present && (present->stat.st_mode & S_IFDIR)) || (old_parent != new_parent)) {
		/* cross directory moves */
		fprintf(stderr, "Cross directory renaming is not implemented yet.\n");
		return ENOTSUP;
	}

	/* if it was present, delete old contents; reference counting is done  */
	if (present) {
		/* TODO what about non dir, non file entries? */
		if (present->stat.st_mode & S_IFDIR) {
			error = udf_remove_directory(new_parent, present, new_name);
		} else {
			error = udf_remove_file(new_parent, present, new_name);
		}
		if (error)
			return error;
	}

	/* insert new_name HARD-linked to the `rename_me' node */
	error = udf_create_directory_entry(new_parent, new_name, rename_me->udf_filetype, rename_me->udf_filechar, rename_me, NULL, &new_node);
	if (error) return error;

	/* extra sanity */
	if (!new_node) return ENOENT;

	/* 3) remove old link and mark directories dirty */
	error = udf_remove_directory_entry(old_parent, rename_me, old_name);
	udf_node_mark_dirty(old_parent);
	udf_node_mark_dirty(new_parent);

	return error;
}


/* VOP_CREATE */
int udf_create_file(struct udf_node *dir_node, char *componentname, struct stat *stat, struct udf_node **new_node) {
	struct udf_log_vol *udf_log_vol;
	struct udf_node *udf_node;
	uint32_t lb_size;
	int error;

	if (!dir_node) return EINVAL;

	udf_log_vol = dir_node->udf_log_vol;
	if (!udf_log_vol) return EINVAL;

	lb_size = udf_log_vol->lb_size;
	if (!udf_confirm_freespace(udf_log_vol, UDF_C_NODE, lb_size))
		return ENOSPC;

	if (udf_open_logvol(dir_node->udf_log_vol))
		return EROFS;

	error = udf_create_directory_entry(dir_node, componentname, UDF_ICB_FILETYPE_RANDOMACCESS, 0, NULL, stat, new_node);
	if ((!error) && (*new_node)) {
		udf_node = *new_node;
		/* update sizes */
		udf_node->stat.st_size    = 0;
		udf_node->stat.st_blksize = dir_node->udf_log_vol->lb_size;
		udf_node->stat.st_blocks  = 0;		/* not 1? */

		udf_node->udf_log_vol->num_files++;

		udf_node_mark_dirty(udf_node);
	}
	return error;
}


/* VOP_MKDIR */
int udf_create_directory(struct udf_node *dir_node, char *componentname, struct stat *stat, struct udf_node **new_node) {
	struct udf_log_vol *udf_log_vol;
	struct udf_node *udf_node, *dummy_node;
	uint32_t lb_size;
	int error;

	if (!dir_node) return EINVAL;

	udf_log_vol = dir_node->udf_log_vol;
	if (!udf_log_vol) return EINVAL;

	lb_size = udf_log_vol->lb_size;
	if (!udf_confirm_freespace(udf_log_vol, UDF_C_NODE, 2*lb_size))
		return ENOSPC;

	if (udf_open_logvol(dir_node->udf_log_vol))
		return EROFS;

	stat->st_mode |= S_IFDIR;
	error = udf_create_directory_entry(dir_node, componentname, UDF_ICB_FILETYPE_DIRECTORY, UDF_FILE_CHAR_DIR, NULL, stat, new_node);
	if ((!error) && (*new_node)) {
		udf_node = *new_node;
		/* update sizes */
		udf_node->stat.st_size    = 0;
		udf_node->stat.st_blksize = dir_node->udf_log_vol->lb_size;
		udf_node->stat.st_blocks  = 0;		/* not 1? */

		udf_node->udf_log_vol->num_directories++;

		udf_node_mark_dirty(udf_node);

		/* create `..' directory entry */
		error = udf_create_directory_entry(udf_node, "..", UDF_ICB_FILETYPE_DIRECTORY, UDF_FILE_CHAR_DIR | UDF_FILE_CHAR_PAR, dir_node, stat, &dummy_node);
		if (error) {
			/* use of _prim for dir counting might not go well due to aborted creation */
			error = udf_remove_directory_prim(dir_node, udf_node, componentname);
		}
	}
	return error;
}



/* really deletes all space referenced to this udf node including descriptor spaces and removes it from the administration */
int udf_unlink_node(struct udf_node *udf_node) {
	struct udf_allocentry *alloc_entry;
	uint32_t lbnum, len;
	uint16_t vpart;
	int error;

	/* just in case its called from outside */
	if (udf_open_logvol(udf_node->udf_log_vol))
		return EROFS;

	/* unlinking changes metadata modification */
	udf_set_timespec_now(&udf_node->stat.st_ctimespec);

	udf_node->link_cnt--;
	udf_node_mark_dirty(udf_node);
	if (udf_node->link_cnt > 0)
		return 0;

	/* trunc node */
	udf_truncate_node(udf_node, (uint64_t) 0);	/* get rid of file contents	*/

	/* free descriptors from dscr_allocs queue */
	TAILQ_FOREACH(alloc_entry, &udf_node->dscr_allocs, next_alloc) {
		vpart = alloc_entry->vpart_num;
		lbnum = alloc_entry->lb_num;
		/* flags = alloc_entry->flags; */
		len   = alloc_entry->len;

		error = udf_release_lbs(udf_node->udf_log_vol, vpart, lbnum, len);
		/* what if an error occures? */
		assert(error == 0);
	}

	/* delete from administration */
	udf_dispose_udf_node(udf_node);

	return 0;
}


/* NOTE: Dont use the EXTENT erased part; its for non sequential WORM only */
/*       UDF 2.3.10.1, ECMA 4/48.14.1.1 */
/*       fid->icb.impl.im_used.flags = udf_rw16(UDF_ADIMP_FLAGS_EXTENT_ERASED); */

static int udf_remove_directory_entry(struct udf_node *dir_node, struct udf_node *udf_node, char *name) {
	struct dirhash       *dirh;
	struct dirhash_entry *dirh_ep;
	struct fileid_desc *fid;
	struct dirent *dirent;
	uint64_t diroffset;
	uint32_t lb_size, namelen, fidsize;
	int      hit, found;
	int      error;

	assert(dir_node);
	assert(udf_node);
	assert(udf_node->udf_log_vol);
	assert(name);

	namelen = strlen(name);
	if (strncmp(name, "..", 3) == 0) {
		printf("Asked to remove `..' parent directory identifier; not allowed!\n");
		return ENOENT;
	}

	if (strncmp(name, ".", 2) == 0) {
		printf("Asked to remove `.' current directory identifier; not allowed!\n");
		return ENOENT;
	}

	/* only lookup in directories XXX DT_COMP also possible XXX */
	if ((dir_node->stat.st_mode & S_IFDIR) == 0)
		return ENOTDIR;

	/* get our dirhash and make sure its read in */
	dirhash_get(&dir_node->dir_hash);
	error = dirhash_fill(dir_node);
	if (error) {
		dirhash_put(dir_node->dir_hash);
		return error;
	}
	dirh = dir_node->dir_hash;

	/* allocate temporary space for fid */
	lb_size = udf_node->udf_log_vol->lb_size;
	fid     = malloc(lb_size);
	dirent  = malloc(sizeof(struct dirent));
	if (!fid || !dirent) {
		error = ENOMEM;
		goto error_out;
	}

	/* search our dirhash hits */
	found = 0;
	dirh_ep = NULL;
	for (;;) {
		hit = dirhash_lookup(dirh, name, namelen, &dirh_ep);
		/* if no hit, abort the search */
		if (!hit)
			break;

		/* check this hit */
		diroffset = dirh_ep->offset;

		/* transfer a new fid/dirent */
		error = udf_read_fid_stream(dir_node, &diroffset, fid, dirent);
		if (error)
			break;

		/* see if its our entry */
		assert(DIRENT_NAMLEN(dirent) == namelen);
		if (strncmp(dirent->d_name, name, namelen) == 0) {
			found = 1;
			break;
		}
	}

	if (!found)
		error = ENOENT;
	if (error)
		goto error_out;

	/* get size of fid and compensate for the read_fid_stream advance */
	fidsize    = udf_fidsize(fid);
	diroffset -= fidsize;

	/* mark fid as deleted */
	fid->file_char |= UDF_FILE_CHAR_DEL;
	bzero(&fid->icb, sizeof(struct long_ad));
	udf_validate_tag_and_crc_sums((union dscrptr *) fid);
	udf_writeout_fid_info(dir_node, fid, diroffset, fidsize);

	/* remove from the dirhash */
	dirhash_mark_freed(dirh, dirh_ep, dirent);

	/* delete node and its administration if refcount indicates so */
	udf_unlink_node(udf_node);

error_out:
	if (fid)
		free(fid);
	if (dirent)
		free(dirent);

	dirhash_put(dir_node->dir_hash);

	return error;
}



/* VOP_REMOVE */
int udf_remove_file(struct udf_node *dir_node, struct udf_node *udf_node, char *componentname) {
	int error;

	if (udf_open_logvol(dir_node->udf_log_vol))
		return EROFS;

	if (udf_node->stat.st_mode & S_IFDIR) {
		/* only remove files with this call */
		return EISDIR;
	}

	error = udf_remove_directory_entry(dir_node, udf_node, componentname);
	if (!error) {
		dir_node->udf_log_vol->num_files--;
	}	/* else? */

	return error;
}


static int udf_remove_directory_prim(struct udf_node *dir_node, struct udf_node *udf_node, char *componentname) {
	int error;

	if (udf_open_logvol(dir_node->udf_log_vol))
		return EROFS;

	/* remove the entry */
	error = udf_remove_directory_entry(dir_node, udf_node, componentname);
	if (!error) {
		dir_node->link_cnt--;
		udf_node_mark_dirty(dir_node);
		dir_node->udf_log_vol->num_directories--;
	} else {
		/* whoah! something went wrong, mark the .. as present again */
		printf("UDF warning: filesystem might by in compromised state\n");
		assert(udf_node);
		udf_node->link_cnt++;
	}

	return error;
}


/* VOP_RMDIR */
int udf_remove_directory(struct udf_node *dir_node, struct udf_node *udf_node, char *componentname) {
	uint32_t num_nodes;
	int error;

	if (!(udf_node->stat.st_mode & S_IFDIR)) {
		/* only remove directories with this call */
		return ENOTDIR;
	}

	error = udf_count_direntries(udf_node, 0, &num_nodes);
	if (error) return error;

	if (num_nodes != 0) return ENOTEMPTY;

	error = udf_remove_directory_prim(dir_node, udf_node, componentname);

	return error;
}


/* end of udf.c */