// These routines are only to be used by ZipArchive.
//
/// <summary>
/// Used by ZipArchive to write the entry to the archive.
/// </summary>
/// <param name="writer">The stream representing the archive to write the entry to.</param>
internal void WriteToStream(Stream writer)
{
Debug.Assert(!IsReadOnly);
Debug.Assert(positionOfCompressedDataInArchive == 0); // we don't use this on read-write archives.
if (uncompressedData != null)
{
if (uncompressedData.CanWrite)
{
throw new Exception("Unclosed writable handle to " + Name + " still exists at Save time");
}
// TODO: Consider using seeks instead of copying to the compressed data stream.
// TODO support not running Deflate but simply skipping (useful for arcping arc files)
//
// Compress the data
MemoryStream compressedDataStream = new RepairedMemoryStream((int)(uncompressedData.Length * 5 / 8));
Stream compressor = new DeflateStream(compressedDataStream, CompressionMode.Compress);
compressor.Write(uncompressedData.GetBuffer(), 0, (int)uncompressedData.Length);
compressor.Close();
// TODO support the NONE case too.
compressionMethod = CompressionMethod.Deflate;
compressedLength = (int)compressedDataStream.Length;
compressedData = compressedDataStream.GetBuffer();
}
Debug.Assert(compressedData != null);
WriteZipFileHeader(writer); // Write the header.
writer.Write(compressedData, 0, compressedLength); // Write the data.
}
// These are the primitive operations
/// <summary>
/// Truncates the archiveFile represented by the ZipArchiveFile to be empty and returns a Stream that can be used
/// to write (binary) data into it.
/// </summary>
/// <returns>A Stream that can be written on. </returns>
public Stream Create()
{
if (IsReadOnly)
{
throw new ApplicationException("Archive is ReadOnly");
}
if (uncompressedData != null && (uncompressedData.CanWrite || uncompressedData.CanRead))
{
throw new ApplicationException("ZipArchiveFile already open.");
}
// abandon any old data
compressedData = null;
positionOfCompressedDataInArchive = 0;
compressedLength = 0;
// We allocate some buffer so that GetBuffer() does not return null.
uncompressedData = new RepairedMemoryStream(256);
return(uncompressedData);
}
