mpv/libdvdread/dvd_udf.c

1003 lines
25 KiB
C

/*
* This code is based on dvdudf by:
* Christian Wolff <scarabaeus@convergence.de>.
*
* Modifications by:
* Billy Biggs <vektor@dumbterm.net>.
* Björn Englund <d4bjorn@dtek.chalmers.se>.
*
* Modified for use with MPlayer, changes contained in libdvdread_changes.diff.
* detailed changelog at http://svn.mplayerhq.hu/mplayer/trunk/
* $Id$
*
* dvdudf: parse and read the UDF volume information of a DVD Video
* Copyright (C) 1999 Christian Wolff for convergence integrated media
* GmbH The author can be reached at scarabaeus@convergence.de, the
* project's page is at http://linuxtv.org/dvd/
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
* 02111-1307, USA. Or, point your browser to
* http://www.gnu.org/copyleft/gpl.html
*/
#include "config.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifndef __MINGW32__
#include <sys/ioctl.h>
#endif
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <inttypes.h>
#include "dvd_reader.h"
#include "dvd_udf.h"
/* Private but located in/shared with dvd_reader.c */
extern int UDFReadBlocksRaw( dvd_reader_t *device, uint32_t lb_number,
size_t block_count, unsigned char *data,
int encrypted );
/* It's required to either fail or deliver all the blocks asked for. */
static int DVDReadLBUDF( dvd_reader_t *device, uint32_t lb_number,
size_t block_count, unsigned char *data,
int encrypted )
{
int ret;
size_t count = block_count;
while(count > 0) {
ret = UDFReadBlocksRaw(device, lb_number, count, data, encrypted);
if(ret <= 0) {
/* One of the reads failed or nothing more to read, too bad.
* We won't even bother returning the reads that went ok. */
return ret;
}
count -= (size_t)ret;
lb_number += (uint32_t)ret;
}
return block_count;
}
#ifndef NULL
#define NULL ((void *)0)
#endif
struct Partition {
int valid;
char VolumeDesc[128];
uint16_t Flags;
uint16_t Number;
char Contents[32];
uint32_t AccessType;
uint32_t Start;
uint32_t Length;
};
struct AD {
uint32_t Location;
uint32_t Length;
uint8_t Flags;
uint16_t Partition;
};
struct extent_ad {
uint32_t location;
uint32_t length;
};
struct avdp_t {
struct extent_ad mvds;
struct extent_ad rvds;
};
struct pvd_t {
uint8_t VolumeIdentifier[32];
uint8_t VolumeSetIdentifier[128];
};
struct lbudf {
uint32_t lb;
uint8_t *data;
};
struct icbmap {
uint32_t lbn;
struct AD file;
uint8_t filetype;
};
struct udf_cache {
int avdp_valid;
struct avdp_t avdp;
int pvd_valid;
struct pvd_t pvd;
int partition_valid;
struct Partition partition;
int rooticb_valid;
struct AD rooticb;
int lb_num;
struct lbudf *lbs;
int map_num;
struct icbmap *maps;
};
typedef enum {
PartitionCache, RootICBCache, LBUDFCache, MapCache, AVDPCache, PVDCache
} UDFCacheType;
extern void *GetUDFCacheHandle(dvd_reader_t *device);
extern void SetUDFCacheHandle(dvd_reader_t *device, void *cache);
void FreeUDFCache(void *cache)
{
struct udf_cache *c = (struct udf_cache *)cache;
if(c == NULL) {
return;
}
if(c->lbs) {
free(c->lbs);
}
if(c->maps) {
free(c->maps);
}
free(c);
}
static int GetUDFCache(dvd_reader_t *device, UDFCacheType type,
uint32_t nr, void *data)
{
int n;
struct udf_cache *c;
if(DVDUDFCacheLevel(device, -1) <= 0) {
return 0;
}
c = (struct udf_cache *)GetUDFCacheHandle(device);
if(c == NULL) {
return 0;
}
switch(type) {
case AVDPCache:
if(c->avdp_valid) {
*(struct avdp_t *)data = c->avdp;
return 1;
}
break;
case PVDCache:
if(c->pvd_valid) {
*(struct pvd_t *)data = c->pvd;
return 1;
}
break;
case PartitionCache:
if(c->partition_valid) {
*(struct Partition *)data = c->partition;
return 1;
}
break;
case RootICBCache:
if(c->rooticb_valid) {
*(struct AD *)data = c->rooticb;
return 1;
}
break;
case LBUDFCache:
for(n = 0; n < c->lb_num; n++) {
if(c->lbs[n].lb == nr) {
*(uint8_t **)data = c->lbs[n].data;
return 1;
}
}
break;
case MapCache:
for(n = 0; n < c->map_num; n++) {
if(c->maps[n].lbn == nr) {
*(struct icbmap *)data = c->maps[n];
return 1;
}
}
break;
default:
break;
}
return 0;
}
static int SetUDFCache(dvd_reader_t *device, UDFCacheType type,
uint32_t nr, void *data)
{
int n;
struct udf_cache *c;
if(DVDUDFCacheLevel(device, -1) <= 0) {
return 0;
}
c = (struct udf_cache *)GetUDFCacheHandle(device);
if(c == NULL) {
c = calloc(1, sizeof(struct udf_cache));
// fprintf(stderr, "calloc: %d\n", sizeof(struct udf_cache));
if(c == NULL) {
return 0;
}
SetUDFCacheHandle(device, c);
}
switch(type) {
case AVDPCache:
c->avdp = *(struct avdp_t *)data;
c->avdp_valid = 1;
break;
case PVDCache:
c->pvd = *(struct pvd_t *)data;
c->pvd_valid = 1;
break;
case PartitionCache:
c->partition = *(struct Partition *)data;
c->partition_valid = 1;
break;
case RootICBCache:
c->rooticb = *(struct AD *)data;
c->rooticb_valid = 1;
break;
case LBUDFCache:
for(n = 0; n < c->lb_num; n++) {
if(c->lbs[n].lb == nr) {
/* replace with new data */
c->lbs[n].data = *(uint8_t **)data;
c->lbs[n].lb = nr;
return 1;
}
}
c->lb_num++;
c->lbs = realloc(c->lbs, c->lb_num * sizeof(struct lbudf));
/*
fprintf(stderr, "realloc lb: %d * %d = %d\n",
c->lb_num, sizeof(struct lbudf),
c->lb_num * sizeof(struct lbudf));
*/
if(c->lbs == NULL) {
c->lb_num = 0;
return 0;
}
c->lbs[n].data = *(uint8_t **)data;
c->lbs[n].lb = nr;
break;
case MapCache:
for(n = 0; n < c->map_num; n++) {
if(c->maps[n].lbn == nr) {
/* replace with new data */
c->maps[n] = *(struct icbmap *)data;
c->maps[n].lbn = nr;
return 1;
}
}
c->map_num++;
c->maps = realloc(c->maps, c->map_num * sizeof(struct icbmap));
/*
fprintf(stderr, "realloc maps: %d * %d = %d\n",
c->map_num, sizeof(struct icbmap),
c->map_num * sizeof(struct icbmap));
*/
if(c->maps == NULL) {
c->map_num = 0;
return 0;
}
c->maps[n] = *(struct icbmap *)data;
c->maps[n].lbn = nr;
break;
default:
return 0;
}
return 1;
}
/* For direct data access, LSB first */
#define GETN1(p) ((uint8_t)data[p])
#define GETN2(p) ((uint16_t)data[p] | ((uint16_t)data[(p) + 1] << 8))
#define GETN3(p) ((uint32_t)data[p] | ((uint32_t)data[(p) + 1] << 8) \
| ((uint32_t)data[(p) + 2] << 16))
#define GETN4(p) ((uint32_t)data[p] \
| ((uint32_t)data[(p) + 1] << 8) \
| ((uint32_t)data[(p) + 2] << 16) \
| ((uint32_t)data[(p) + 3] << 24))
/* This is wrong with regard to endianess */
#define GETN(p, n, target) memcpy(target, &data[p], n)
static int Unicodedecode( uint8_t *data, int len, char *target )
{
int p = 1, i = 0;
if( ( data[ 0 ] == 8 ) || ( data[ 0 ] == 16 ) ) do {
if( data[ 0 ] == 16 ) p++; /* Ignore MSB of unicode16 */
if( p < len ) {
target[ i++ ] = data[ p++ ];
}
} while( p < len );
target[ i ] = '\0';
return 0;
}
static int UDFDescriptor( uint8_t *data, uint16_t *TagID )
{
*TagID = GETN2(0);
// TODO: check CRC 'n stuff
return 0;
}
static int UDFExtentAD( uint8_t *data, uint32_t *Length, uint32_t *Location )
{
*Length = GETN4(0);
*Location = GETN4(4);
return 0;
}
static int UDFShortAD( uint8_t *data, struct AD *ad,
struct Partition *partition )
{
ad->Length = GETN4(0);
ad->Flags = ad->Length >> 30;
ad->Length &= 0x3FFFFFFF;
ad->Location = GETN4(4);
ad->Partition = partition->Number; // use number of current partition
return 0;
}
static int UDFLongAD( uint8_t *data, struct AD *ad )
{
ad->Length = GETN4(0);
ad->Flags = ad->Length >> 30;
ad->Length &= 0x3FFFFFFF;
ad->Location = GETN4(4);
ad->Partition = GETN2(8);
//GETN(10, 6, Use);
return 0;
}
static int UDFExtAD( uint8_t *data, struct AD *ad )
{
ad->Length = GETN4(0);
ad->Flags = ad->Length >> 30;
ad->Length &= 0x3FFFFFFF;
ad->Location = GETN4(12);
ad->Partition = GETN2(16);
//GETN(10, 6, Use);
return 0;
}
static int UDFICB( uint8_t *data, uint8_t *FileType, uint16_t *Flags )
{
*FileType = GETN1(11);
*Flags = GETN2(18);
return 0;
}
static int UDFPartition( uint8_t *data, uint16_t *Flags, uint16_t *Number,
char *Contents, uint32_t *Start, uint32_t *Length )
{
*Flags = GETN2(20);
*Number = GETN2(22);
GETN(24, 32, Contents);
*Start = GETN4(188);
*Length = GETN4(192);
return 0;
}
/**
* Reads the volume descriptor and checks the parameters. Returns 0 on OK, 1
* on error.
*/
static int UDFLogVolume( uint8_t *data, char *VolumeDescriptor )
{
uint32_t lbsize, MT_L, N_PM;
Unicodedecode(&data[84], 128, VolumeDescriptor);
lbsize = GETN4(212); // should be 2048
MT_L = GETN4(264); // should be 6
N_PM = GETN4(268); // should be 1
if (lbsize != DVD_VIDEO_LB_LEN) return 1;
return 0;
}
static int UDFFileEntry( uint8_t *data, uint8_t *FileType,
struct Partition *partition, struct AD *ad )
{
uint16_t flags;
uint32_t L_EA, L_AD;
unsigned int p;
UDFICB( &data[ 16 ], FileType, &flags );
/* Init ad for an empty file (i.e. there isn't a AD, L_AD == 0 ) */
ad->Length = GETN4( 60 ); // Really 8 bytes a 56
ad->Flags = 0;
ad->Location = 0; // what should we put here?
ad->Partition = partition->Number; // use number of current partition
L_EA = GETN4( 168 );
L_AD = GETN4( 172 );
p = 176 + L_EA;
while( p < 176 + L_EA + L_AD ) {
switch( flags & 0x0007 ) {
case 0: UDFShortAD( &data[ p ], ad, partition ); p += 8; break;
case 1: UDFLongAD( &data[ p ], ad ); p += 16; break;
case 2: UDFExtAD( &data[ p ], ad ); p += 20; break;
case 3:
switch( L_AD ) {
case 8: UDFShortAD( &data[ p ], ad, partition ); break;
case 16: UDFLongAD( &data[ p ], ad ); break;
case 20: UDFExtAD( &data[ p ], ad ); break;
}
p += L_AD;
break;
default:
p += L_AD; break;
}
}
return 0;
}
static int UDFFileIdentifier( uint8_t *data, uint8_t *FileCharacteristics,
char *FileName, struct AD *FileICB )
{
uint8_t L_FI;
uint16_t L_IU;
*FileCharacteristics = GETN1(18);
L_FI = GETN1(19);
UDFLongAD(&data[20], FileICB);
L_IU = GETN2(36);
if (L_FI) Unicodedecode(&data[38 + L_IU], L_FI, FileName);
else FileName[0] = '\0';
return 4 * ((38 + L_FI + L_IU + 3) / 4);
}
/**
* Maps ICB to FileAD
* ICB: Location of ICB of directory to scan
* FileType: Type of the file
* File: Location of file the ICB is pointing to
* return 1 on success, 0 on error;
*/
static int UDFMapICB( dvd_reader_t *device, struct AD ICB, uint8_t *FileType,
struct Partition *partition, struct AD *File )
{
uint8_t LogBlock[DVD_VIDEO_LB_LEN];
uint32_t lbnum;
uint16_t TagID;
struct icbmap tmpmap;
lbnum = partition->Start + ICB.Location;
tmpmap.lbn = lbnum;
if(GetUDFCache(device, MapCache, lbnum, &tmpmap)) {
*FileType = tmpmap.filetype;
*File = tmpmap.file;
return 1;
}
do {
if( DVDReadLBUDF( device, lbnum++, 1, LogBlock, 0 ) <= 0 ) {
TagID = 0;
} else {
UDFDescriptor( LogBlock, &TagID );
}
if( TagID == 261 ) {
UDFFileEntry( LogBlock, FileType, partition, File );
tmpmap.file = *File;
tmpmap.filetype = *FileType;
SetUDFCache(device, MapCache, tmpmap.lbn, &tmpmap);
return 1;
};
} while( ( lbnum <= partition->Start + ICB.Location + ( ICB.Length - 1 )
/ DVD_VIDEO_LB_LEN ) && ( TagID != 261 ) );
return 0;
}
/**
* Dir: Location of directory to scan
* FileName: Name of file to look for
* FileICB: Location of ICB of the found file
* return 1 on success, 0 on error;
*/
static int UDFScanDir( dvd_reader_t *device, struct AD Dir, char *FileName,
struct Partition *partition, struct AD *FileICB,
int cache_file_info)
{
char filename[ MAX_UDF_FILE_NAME_LEN ];
uint8_t directory[ 2 * DVD_VIDEO_LB_LEN ];
uint32_t lbnum;
uint16_t TagID;
uint8_t filechar;
unsigned int p;
uint8_t *cached_dir = NULL;
uint32_t dir_lba;
struct AD tmpICB;
int found = 0;
int in_cache = 0;
/* Scan dir for ICB of file */
lbnum = partition->Start + Dir.Location;
if(DVDUDFCacheLevel(device, -1) > 0) {
/* caching */
if(!GetUDFCache(device, LBUDFCache, lbnum, &cached_dir)) {
dir_lba = (Dir.Length + DVD_VIDEO_LB_LEN) / DVD_VIDEO_LB_LEN;
if((cached_dir = malloc(dir_lba * DVD_VIDEO_LB_LEN)) == NULL) {
return 0;
}
if( DVDReadLBUDF( device, lbnum, dir_lba, cached_dir, 0) <= 0 ) {
free(cached_dir);
cached_dir = NULL;
}
/*
if(cached_dir) {
fprintf(stderr, "malloc dir: %d\n",
dir_lba * DVD_VIDEO_LB_LEN);
}
*/
SetUDFCache(device, LBUDFCache, lbnum, &cached_dir);
} else {
in_cache = 1;
}
if(cached_dir == NULL) {
return 0;
}
p = 0;
while( p < Dir.Length ) {
UDFDescriptor( &cached_dir[ p ], &TagID );
if( TagID == 257 ) {
p += UDFFileIdentifier( &cached_dir[ p ], &filechar,
filename, &tmpICB );
if(cache_file_info && !in_cache) {
uint8_t tmpFiletype;
struct AD tmpFile;
if( !strcasecmp( FileName, filename ) ) {
*FileICB = tmpICB;
found = 1;
}
UDFMapICB(device, tmpICB, &tmpFiletype,
partition, &tmpFile);
} else {
if( !strcasecmp( FileName, filename ) ) {
*FileICB = tmpICB;
return 1;
}
}
} else {
if(cache_file_info && (!in_cache) && found) {
return 1;
}
return 0;
}
}
if(cache_file_info && (!in_cache) && found) {
return 1;
}
return 0;
}
if( DVDReadLBUDF( device, lbnum, 2, directory, 0 ) <= 0 ) {
return 0;
}
p = 0;
while( p < Dir.Length ) {
if( p > DVD_VIDEO_LB_LEN ) {
++lbnum;
p -= DVD_VIDEO_LB_LEN;
Dir.Length -= DVD_VIDEO_LB_LEN;
if( DVDReadLBUDF( device, lbnum, 2, directory, 0 ) <= 0 ) {
return 0;
}
}
UDFDescriptor( &directory[ p ], &TagID );
if( TagID == 257 ) {
p += UDFFileIdentifier( &directory[ p ], &filechar,
filename, FileICB );
if( !strcasecmp( FileName, filename ) ) {
return 1;
}
} else {
return 0;
}
}
return 0;
}
static int UDFGetAVDP( dvd_reader_t *device,
struct avdp_t *avdp)
{
uint8_t Anchor[ DVD_VIDEO_LB_LEN ];
uint32_t lbnum, MVDS_location, MVDS_length;
uint16_t TagID;
uint32_t lastsector;
int terminate;
struct avdp_t;
if(GetUDFCache(device, AVDPCache, 0, avdp)) {
return 1;
}
/* Find Anchor */
lastsector = 0;
lbnum = 256; /* Try #1, prime anchor */
terminate = 0;
for(;;) {
if( DVDReadLBUDF( device, lbnum, 1, Anchor, 0 ) > 0 ) {
UDFDescriptor( Anchor, &TagID );
} else {
TagID = 0;
}
if (TagID != 2) {
/* Not an anchor */
if( terminate ) return 0; /* Final try failed */
if( lastsector ) {
/* We already found the last sector. Try #3, alternative
* backup anchor. If that fails, don't try again.
*/
lbnum = lastsector;
terminate = 1;
} else {
/* TODO: Find last sector of the disc (this is optional). */
if( lastsector ) {
/* Try #2, backup anchor */
lbnum = lastsector - 256;
} else {
/* Unable to find last sector */
return 0;
}
}
} else {
/* It's an anchor! We can leave */
break;
}
}
/* Main volume descriptor */
UDFExtentAD( &Anchor[ 16 ], &MVDS_length, &MVDS_location );
avdp->mvds.location = MVDS_location;
avdp->mvds.length = MVDS_length;
/* Backup volume descriptor */
UDFExtentAD( &Anchor[ 24 ], &MVDS_length, &MVDS_location );
avdp->rvds.location = MVDS_location;
avdp->rvds.length = MVDS_length;
SetUDFCache(device, AVDPCache, 0, avdp);
return 1;
}
/**
* Looks for partition on the disc. Returns 1 if partition found, 0 on error.
* partnum: Number of the partition, starting at 0.
* part: structure to fill with the partition information
*/
static int UDFFindPartition( dvd_reader_t *device, int partnum,
struct Partition *part )
{
uint8_t LogBlock[ DVD_VIDEO_LB_LEN ];
uint32_t lbnum, MVDS_location, MVDS_length;
uint16_t TagID;
int i, volvalid;
struct avdp_t avdp;
if(!UDFGetAVDP(device, &avdp)) {
return 0;
}
/* Main volume descriptor */
MVDS_location = avdp.mvds.location;
MVDS_length = avdp.mvds.length;
part->valid = 0;
volvalid = 0;
part->VolumeDesc[ 0 ] = '\0';
i = 1;
do {
/* Find Volume Descriptor */
lbnum = MVDS_location;
do {
if( DVDReadLBUDF( device, lbnum++, 1, LogBlock, 0 ) <= 0 ) {
TagID = 0;
} else {
UDFDescriptor( LogBlock, &TagID );
}
if( ( TagID == 5 ) && ( !part->valid ) ) {
/* Partition Descriptor */
UDFPartition( LogBlock, &part->Flags, &part->Number,
part->Contents, &part->Start, &part->Length );
part->valid = ( partnum == part->Number );
} else if( ( TagID == 6 ) && ( !volvalid ) ) {
/* Logical Volume Descriptor */
if( UDFLogVolume( LogBlock, part->VolumeDesc ) ) {
/* TODO: sector size wrong! */
} else {
volvalid = 1;
}
}
} while( ( lbnum <= MVDS_location + ( MVDS_length - 1 )
/ DVD_VIDEO_LB_LEN ) && ( TagID != 8 )
&& ( ( !part->valid ) || ( !volvalid ) ) );
if( ( !part->valid) || ( !volvalid ) ) {
/* Backup volume descriptor */
MVDS_location = avdp.mvds.location;
MVDS_length = avdp.mvds.length;
}
} while( i-- && ( ( !part->valid ) || ( !volvalid ) ) );
/* We only care for the partition, not the volume */
return part->valid;
}
uint32_t UDFFindFile( dvd_reader_t *device, char *filename,
uint32_t *filesize )
{
uint8_t LogBlock[ DVD_VIDEO_LB_LEN ];
uint32_t lbnum;
uint16_t TagID;
struct Partition partition;
struct AD RootICB, File, ICB;
char tokenline[ MAX_UDF_FILE_NAME_LEN ];
char *token;
uint8_t filetype;
*filesize = 0;
tokenline[0] = '\0';
strcat( tokenline, filename );
if(!(GetUDFCache(device, PartitionCache, 0, &partition) &&
GetUDFCache(device, RootICBCache, 0, &RootICB))) {
/* Find partition, 0 is the standard location for DVD Video.*/
if( !UDFFindPartition( device, 0, &partition ) ) return 0;
SetUDFCache(device, PartitionCache, 0, &partition);
/* Find root dir ICB */
lbnum = partition.Start;
do {
if( DVDReadLBUDF( device, lbnum++, 1, LogBlock, 0 ) <= 0 ) {
TagID = 0;
} else {
UDFDescriptor( LogBlock, &TagID );
}
/* File Set Descriptor */
if( TagID == 256 ) { // File Set Descriptor
UDFLongAD( &LogBlock[ 400 ], &RootICB );
}
} while( ( lbnum < partition.Start + partition.Length )
&& ( TagID != 8 ) && ( TagID != 256 ) );
/* Sanity checks. */
if( TagID != 256 ) return 0;
if( RootICB.Partition != 0 ) return 0;
SetUDFCache(device, RootICBCache, 0, &RootICB);
}
/* Find root dir */
if( !UDFMapICB( device, RootICB, &filetype, &partition, &File ) ) return 0;
if( filetype != 4 ) return 0; /* Root dir should be dir */
{
int cache_file_info = 0;
/* Tokenize filepath */
token = strtok(tokenline, "/");
while( token != NULL ) {
if( !UDFScanDir( device, File, token, &partition, &ICB,
cache_file_info)) {
return 0;
}
if( !UDFMapICB( device, ICB, &filetype, &partition, &File ) ) {
return 0;
}
if(!strcmp(token, "VIDEO_TS")) {
cache_file_info = 1;
}
token = strtok( NULL, "/" );
}
}
/* Sanity check. */
if( File.Partition != 0 ) return 0;
*filesize = File.Length;
/* Hack to not return partition.Start for empty files. */
if( !File.Location )
return 0;
else
return partition.Start + File.Location;
}
/**
* Gets a Descriptor .
* Returns 1 if descriptor found, 0 on error.
* id, tagid of descriptor
* bufsize, size of BlockBuf (must be >= DVD_VIDEO_LB_LEN).
*/
static int UDFGetDescriptor( dvd_reader_t *device, int id,
uint8_t *descriptor, int bufsize)
{
uint32_t lbnum, MVDS_location, MVDS_length;
struct avdp_t avdp;
uint16_t TagID;
uint32_t lastsector;
int i, terminate;
int desc_found = 0;
/* Find Anchor */
lastsector = 0;
lbnum = 256; /* Try #1, prime anchor */
terminate = 0;
if(bufsize < DVD_VIDEO_LB_LEN) {
return 0;
}
if(!UDFGetAVDP(device, &avdp)) {
return 0;
}
/* Main volume descriptor */
MVDS_location = avdp.mvds.location;
MVDS_length = avdp.mvds.length;
i = 1;
do {
/* Find Descriptor */
lbnum = MVDS_location;
do {
if( DVDReadLBUDF( device, lbnum++, 1, descriptor, 0 ) <= 0 ) {
TagID = 0;
} else {
UDFDescriptor( descriptor, &TagID );
}
if( (TagID == id) && ( !desc_found ) ) {
/* Descriptor */
desc_found = 1;
}
} while( ( lbnum <= MVDS_location + ( MVDS_length - 1 )
/ DVD_VIDEO_LB_LEN ) && ( TagID != 8 )
&& ( !desc_found) );
if( !desc_found ) {
/* Backup volume descriptor */
MVDS_location = avdp.rvds.location;
MVDS_length = avdp.rvds.length;
}
} while( i-- && ( !desc_found ) );
return desc_found;
}
static int UDFGetPVD(dvd_reader_t *device, struct pvd_t *pvd)
{
uint8_t pvd_buf[DVD_VIDEO_LB_LEN];
if(GetUDFCache(device, PVDCache, 0, pvd)) {
return 1;
}
if(!UDFGetDescriptor( device, 1, pvd_buf, sizeof(pvd_buf))) {
return 0;
}
memcpy(pvd->VolumeIdentifier, &pvd_buf[24], 32);
memcpy(pvd->VolumeSetIdentifier, &pvd_buf[72], 128);
SetUDFCache(device, PVDCache, 0, pvd);
return 1;
}
/**
* Gets the Volume Identifier string, in 8bit unicode (latin-1)
* volid, place to put the string
* volid_size, size of the buffer volid points to
* returns the size of buffer needed for all data
*/
int UDFGetVolumeIdentifier(dvd_reader_t *device, char *volid,
unsigned int volid_size)
{
struct pvd_t pvd;
unsigned int volid_len;
/* get primary volume descriptor */
if(!UDFGetPVD(device, &pvd)) {
return 0;
}
volid_len = pvd.VolumeIdentifier[31];
if(volid_len > 31) {
/* this field is only 32 bytes something is wrong */
volid_len = 31;
}
if(volid_size > volid_len) {
volid_size = volid_len;
}
Unicodedecode(pvd.VolumeIdentifier, volid_size, volid);
return volid_len;
}
/**
* Gets the Volume Set Identifier, as a 128-byte dstring (not decoded)
* WARNING This is not a null terminated string
* volsetid, place to put the data
* volsetid_size, size of the buffer volsetid points to
* the buffer should be >=128 bytes to store the whole volumesetidentifier
* returns the size of the available volsetid information (128)
* or 0 on error
*/
int UDFGetVolumeSetIdentifier(dvd_reader_t *device, uint8_t *volsetid,
unsigned int volsetid_size)
{
struct pvd_t pvd;
/* get primary volume descriptor */
if(!UDFGetPVD(device, &pvd)) {
return 0;
}
if(volsetid_size > 128) {
volsetid_size = 128;
}
memcpy(volsetid, pvd.VolumeSetIdentifier, volsetid_size);
return 128;
}