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Enhancement : TorrentZip format support

Open optyfr opened this issue 1 year ago • 0 comments

I'm trying to figure out what would be needed to adapt Zip4J to generate TorrentZip which is same as ZIP but with more restrictive rules explained here : https://www.romvault.com/trrntzip_explained.pdf But before going further, while trying to reproduce same zipped files with zip4j, I may have found some bugs in central directory reported by zipinfo :

  • compression subtype is reported as "superfast" while it was ultra (compressed data result is indeed ultra)
  • extended local header is indicated as present even with setWriteExtendedLocalFileHeader(false)

To be compliant, there will be a need to set versionMadeBy field to 0 and other things described in the document and lastly the need to calculate the checksum of the entire central directory and set a comment on the zip file containing that CRC

optyfr avatar Mar 12 '23 18:03 optyfr