Implement path table traversal in ISO9660.

This commit is contained in:
2019-07-29 04:00:51 +01:00
parent 28ad9dac86
commit 93b5c483ec
4 changed files with 155 additions and 4 deletions

View File

@@ -75,6 +75,14 @@ namespace DiscImageChef.Filesystems.ISO9660
? DecodeHighSierraDirectory(directoryBuffer)
: DecodeIsoDirectory(directoryBuffer);
if(usePathTable)
foreach(DecodedDirectoryEntry subDirectory in cdi
? GetSubdirsFromCdiPathTable(currentPath)
: highSierra
? GetSubdirsFromHighSierraPathTable(currentPath)
: GetSubdirsFromIsoPathTable(currentPath))
currentDirectory[subDirectory.Filename] = subDirectory;
directoryCache.Add(currentPath, currentDirectory);
}
@@ -142,6 +150,12 @@ namespace DiscImageChef.Filesystems.ISO9660
Timestamp = DecodeHighSierraDateTime(record.date)
};
if(entry.Flags.HasFlag(FileFlags.Directory) && usePathTable)
{
entryOff += record.length;
continue;
}
if(!entries.ContainsKey(entry.Filename)) entries.Add(entry.Filename, entry);
entryOff += record.length;
@@ -187,6 +201,12 @@ namespace DiscImageChef.Filesystems.ISO9660
Timestamp = DecodeIsoDateTime(record.date)
};
if(entry.Flags.HasFlag(FileFlags.Directory) && usePathTable)
{
entryOff += record.length;
continue;
}
// TODO: XA
int systemAreaStart = entryOff + record.name_len + Marshal.SizeOf<DirectoryRecord>();
int systemAreaLength = record.length - record.name_len - Marshal.SizeOf<DirectoryRecord>();
@@ -700,5 +720,117 @@ namespace DiscImageChef.Filesystems.ISO9660
}
}
}
PathTableEntryInternal[] GetPathTableEntries(string path)
{
IEnumerable<PathTableEntryInternal> tableEntries = new PathTableEntryInternal[0];
List<PathTableEntryInternal> pathTableList = new List<PathTableEntryInternal>(pathTable);
if(path == "" || path == "/") tableEntries = pathTable.Where(p => p.Parent == 1 && p != pathTable[0]);
else
{
string cutPath = path.StartsWith("/", StringComparison.Ordinal)
? path.Substring(1).ToLower(CultureInfo.CurrentUICulture)
: path.ToLower(CultureInfo.CurrentUICulture);
string[] pieces = cutPath.Split(new[] {'/'}, StringSplitOptions.RemoveEmptyEntries);
int currentParent = 1;
int currentPiece = 0;
while(currentPiece < pieces.Length)
{
PathTableEntryInternal currentEntry = pathTable.FirstOrDefault(p => p.Parent == currentParent &&
p.Name.ToLower(CultureInfo
.CurrentUICulture) ==
pieces[currentPiece]);
if(currentEntry is null) break;
currentPiece++;
currentParent = pathTableList.IndexOf(currentEntry) + 1;
}
tableEntries = pathTable.Where(p => p.Parent == currentParent);
}
return tableEntries.ToArray();
}
DecodedDirectoryEntry[] GetSubdirsFromCdiPathTable(string path) => throw new NotImplementedException();
DecodedDirectoryEntry[] GetSubdirsFromIsoPathTable(string path)
{
PathTableEntryInternal[] tableEntries = GetPathTableEntries(path);
List<DecodedDirectoryEntry> entries = new List<DecodedDirectoryEntry>();
foreach(PathTableEntryInternal tEntry in tableEntries)
{
byte[] sector = image.ReadSector(tEntry.Extent);
DirectoryRecord record =
Marshal.ByteArrayToStructureLittleEndian<DirectoryRecord>(sector, 0,
Marshal.SizeOf<DirectoryRecord>());
if(record.length == 0) break;
DecodedDirectoryEntry entry = new DecodedDirectoryEntry
{
Extent = record.size == 0 ? 0 : record.extent,
Size = record.size,
Flags = record.flags,
Filename = tEntry.Name,
FileUnitSize = record.file_unit_size,
Interleave = record.interleave,
VolumeSequenceNumber = record.volume_sequence_number,
Timestamp = DecodeIsoDateTime(record.date)
};
// TODO: XA
int systemAreaStart = record.name_len + Marshal.SizeOf<DirectoryRecord>();
int systemAreaLength = record.length - record.name_len - Marshal.SizeOf<DirectoryRecord>();
if(systemAreaStart % 2 != 0)
{
systemAreaStart++;
systemAreaLength--;
}
DecodeSystemArea(sector, systemAreaStart, systemAreaStart + systemAreaLength, ref entry, out _);
entries.Add(entry);
}
return entries.ToArray();
}
DecodedDirectoryEntry[] GetSubdirsFromHighSierraPathTable(string path)
{
PathTableEntryInternal[] tableEntries = GetPathTableEntries(path);
List<DecodedDirectoryEntry> entries = new List<DecodedDirectoryEntry>();
foreach(PathTableEntryInternal tEntry in tableEntries)
{
byte[] sector = image.ReadSector(tEntry.Extent);
HighSierraDirectoryRecord record =
Marshal.ByteArrayToStructureLittleEndian<HighSierraDirectoryRecord>(sector, 0,
Marshal
.SizeOf<
HighSierraDirectoryRecord
>());
DecodedDirectoryEntry entry = new DecodedDirectoryEntry
{
Extent = record.size == 0 ? 0 : record.extent,
Size = record.size,
Flags = record.flags,
Filename = tEntry.Name,
Interleave = record.interleave,
VolumeSequenceNumber = record.volume_sequence_number,
Timestamp = DecodeHighSierraDateTime(record.date)
};
entries.Add(entry);
}
return entries.ToArray();
}
}
}