void ModifyEntry(HfsFile workFile, HfsUpdate update)
{
workFile.WriteLocalEntryHeader(update);
long dataStart = workFile.baseStream_.Position;
// TODO: This is slow if the changes don't effect the data!!
if (update.Entry.IsFile && (update.Filename != null))
{
using (Stream output = workFile.GetOutputStream(update.OutEntry))
{
using (Stream source = this.GetInputStream(update.Entry))
{
CopyBytes(update, output, source, source.Length, true);
}
}
}
long dataEnd = workFile.baseStream_.Position;
update.Entry.CompressedSize = dataEnd - dataStart;
}
void WriteLocalEntryHeader(HfsUpdate update)
{
HfsEntry entry = update.OutEntry;
// TODO: Local offset will require adjusting for multi-disk Hfs files.
entry.Offset = baseStream_.Position;
// TODO: Need to clear any entry flags that dont make sense or throw an exception here.
if (update.Command != UpdateCommand.Copy)
{
}
// Write the local file header
WriteLEInt(HfsConstants.LocalHeaderSignature);
WriteLEShort(entry.Version);
WriteLEShort(entry.Flags);
WriteLEShort((byte)entry.CompressionMethod);
WriteLEInt((int)entry.DosTime);
if (!entry.HasCrc)
{
// Note patch address for updating CRC later.
update.CrcPatchOffset = baseStream_.Position;
WriteLEInt((int)0);
}
else
{
WriteLEInt(unchecked((int)entry.Crc));
}
if ((entry.CompressedSize < 0) || (entry.Size < 0))
{
update.SizePatchOffset = baseStream_.Position;
}
WriteLEInt((int)entry.CompressedSize);
WriteLEInt((int)entry.Size);
byte[] name = HfsConstants.ConvertToArray(entry.Flags, entry.Name);
if (name.Length > 0xFFFF)
{
throw new HfsException("Entry name too long.");
}
entry.ExtraData = new byte[0];
WriteLEShort(name.Length);
WriteLEShort(entry.ExtraData.Length);
HfsXorCipher.XorBlockWithKey(name, HfsXorCipher.XorTruths, (int)baseStream_.Position);
if (name.Length > 0)
{
baseStream_.Write(name, 0, name.Length);
}
if (entry.ExtraData.Length > 0)
{
baseStream_.Write(entry.ExtraData, 0, entry.ExtraData.Length);
}
}
void CopyEntryDirect(HfsFile workFile, HfsUpdate update, ref long destinationPosition)
{
bool skipOver = false;
if (update.Entry.Offset == destinationPosition)
{
skipOver = true;
}
if (!skipOver)
{
baseStream_.Position = destinationPosition;
workFile.WriteLocalEntryHeader(update);
destinationPosition = baseStream_.Position;
}
long sourcePosition = 0;
const int NameLengthOffset = 26;
// TODO: Add base for SFX friendly handling
long entryDataOffset = update.Entry.Offset + NameLengthOffset;
baseStream_.Seek(entryDataOffset, SeekOrigin.Begin);
// Clumsy way of handling retrieving the original name and extra data length for now.
// TODO: Stop re-reading name and data length in CopyEntryDirect.
uint nameLength = ReadLEUshort();
uint extraLength = ReadLEUshort();
sourcePosition = baseStream_.Position + nameLength + extraLength;
if (skipOver)
{
if (update.OffsetBasedSize != -1)
destinationPosition += update.OffsetBasedSize;
else
// TODO: Find out why this calculation comes up 4 bytes short on some entries in ODT (Office Document Text) archives.
// WinHfs produces a warning on these entries:
// "caution: value of lrec.csize (compressed size) changed from ..."
destinationPosition +=
(sourcePosition - entryDataOffset) + NameLengthOffset + // Header size
update.Entry.CompressedSize + GetDescriptorSize(update);
}
else
{
if (update.Entry.CompressedSize > 0)
{
CopyEntryDataDirect(update, baseStream_, false, ref destinationPosition, ref sourcePosition);
}
CopyDescriptorBytesDirect(update, baseStream_, ref destinationPosition, sourcePosition);
}
}
/// <summary>
/// Get the size of the source descriptor for a <see cref="HfsUpdate"/>.
/// </summary>
/// <param name="update">The update to get the size for.</param>
/// <returns>The descriptor size, zero if there isnt one.</returns>
int GetDescriptorSize(HfsUpdate update)
{
int result = 0;
return result;
}
void CopyEntry(HfsFile workFile, HfsUpdate update)
{
workFile.WriteLocalEntryHeader(update);
if (update.Entry.CompressedSize > 0)
{
const int NameLengthOffset = 26;
long entryDataOffset = update.Entry.Offset + NameLengthOffset;
// TODO: This wont work for SFX files!
baseStream_.Seek(entryDataOffset, SeekOrigin.Begin);
uint nameLength = ReadLEUshort();
uint extraLength = ReadLEUshort();
baseStream_.Seek(nameLength + extraLength, SeekOrigin.Current);
CopyBytes(update, workFile.baseStream_, baseStream_, update.Entry.CompressedSize, false);
}
CopyDescriptorBytes(update, workFile.baseStream_, baseStream_);
}
void CopyEntryDataDirect(HfsUpdate update, Stream stream, bool updateCrc, ref long destinationPosition, ref long sourcePosition)
{
long bytesToCopy = update.Entry.CompressedSize;
// NOTE: Compressed size is updated elsewhere.
Crc32 crc = new Crc32();
byte[] buffer = GetBuffer();
long targetBytes = bytesToCopy;
long totalBytesRead = 0;
int bytesRead;
do
{
int readSize = buffer.Length;
if (bytesToCopy < readSize)
{
readSize = (int)bytesToCopy;
}
stream.Position = sourcePosition;
bytesRead = stream.Read(buffer, 0, readSize);
if (bytesRead > 0)
{
if (updateCrc)
{
crc.Update(buffer, 0, bytesRead);
}
stream.Position = destinationPosition;
stream.Write(buffer, 0, bytesRead);
destinationPosition += bytesRead;
sourcePosition += bytesRead;
bytesToCopy -= bytesRead;
totalBytesRead += bytesRead;
}
}
while ((bytesRead > 0) && (bytesToCopy > 0));
if (totalBytesRead != targetBytes)
{
throw new HfsException(string.Format("Failed to copy bytes expected {0} read {1}", targetBytes, totalBytesRead));
}
if (updateCrc)
{
update.OutEntry.Crc = crc.Value;
}
}
void CopyDescriptorBytesDirect(HfsUpdate update, Stream stream, ref long destinationPosition, long sourcePosition)
{
int bytesToCopy = GetDescriptorSize(update);
while (bytesToCopy > 0)
{
int readSize = (int)bytesToCopy;
byte[] buffer = GetBuffer();
stream.Position = sourcePosition;
int bytesRead = stream.Read(buffer, 0, readSize);
if (bytesRead > 0)
{
stream.Position = destinationPosition;
stream.Write(buffer, 0, bytesRead);
bytesToCopy -= bytesRead;
destinationPosition += bytesRead;
sourcePosition += bytesRead;
}
else
{
throw new HfsException("Unxpected end of stream");
}
}
}
void CopyDescriptorBytes(HfsUpdate update, Stream dest, Stream source)
{
int bytesToCopy = GetDescriptorSize(update);
if (bytesToCopy > 0)
{
byte[] buffer = GetBuffer();
while (bytesToCopy > 0)
{
int readSize = Math.Min(buffer.Length, bytesToCopy);
int bytesRead = source.Read(buffer, 0, readSize);
if (bytesRead > 0)
{
dest.Write(buffer, 0, bytesRead);
bytesToCopy -= bytesRead;
}
else
{
throw new HfsException("Unxpected end of stream");
}
}
}
}
void CopyBytes(HfsUpdate update, Stream destination, Stream source,
long bytesToCopy, bool updateCrc)
{
if (destination == source)
{
throw new InvalidOperationException("Destination and source are the same");
}
// NOTE: Compressed size is updated elsewhere.
Crc32 crc = new Crc32();
byte[] buffer = GetBuffer();
long targetBytes = bytesToCopy;
long totalBytesRead = 0;
int bytesRead;
do
{
int readSize = buffer.Length;
if (bytesToCopy < readSize)
{
readSize = (int)bytesToCopy;
}
bytesRead = source.Read(buffer, 0, readSize);
if (bytesRead > 0)
{
if (updateCrc)
{
crc.Update(buffer, 0, bytesRead);
}
destination.Write(buffer, 0, bytesRead);
bytesToCopy -= bytesRead;
totalBytesRead += bytesRead;
}
}
while ((bytesRead > 0) && (bytesToCopy > 0));
if (totalBytesRead != targetBytes)
{
throw new HfsException(string.Format("Failed to copy bytes expected {0} read {1}", targetBytes, totalBytesRead));
}
if (updateCrc)
{
update.OutEntry.Crc = crc.Value;
}
}
void AddUpdate(HfsUpdate update)
{
contentsEdited_ = true;
int index = FindExistingUpdate(update.Entry.Name);
if (index >= 0)
{
if (updates_[index] == null)
{
updateCount_ += 1;
}
// Direct replacement is faster than delete and add.
updates_[index] = update;
}
else
{
index = updates_.Add(update);
updateCount_ += 1;
updateIndex_.Add(update.Entry.Name, index);
}
}
void AddEntry(HfsFile workFile, HfsUpdate update)
{
Stream source = null;
if (update.Entry.IsFile)
{
source = update.GetSource();
if (source == null)
{
source = updateDataSource_.GetSource(update.Entry, update.Filename);
}
}
if (source != null)
{
using (source)
{
long sourceStreamLength = source.Length;
if (update.OutEntry.Size < 0)
{
update.OutEntry.Size = sourceStreamLength;
}
else
{
// Check for errant entries.
if (update.OutEntry.Size != sourceStreamLength)
{
throw new HfsException("Entry size/stream size mismatch");
}
}
workFile.WriteLocalEntryHeader(update);
long dataStart = workFile.baseStream_.Position;
update.OutEntry.DataOffset = dataStart;
using (Stream output = workFile.GetOutputStream(update.OutEntry))
{
CopyBytes(update, output, source, sourceStreamLength, true);
}
long dataEnd = workFile.baseStream_.Position;
update.OutEntry.CompressedSize = update.OutEntry.Size = dataEnd - dataStart;
}
}
else
{
workFile.WriteLocalEntryHeader(update);
update.OutEntry.CompressedSize = 0;
}
}
