Crate gzip_header

A library to decode and encode headers for the gzip format. The library also contains a reader absctraction over a CRC checksum hasher.

A file in the gzip format contains a gzip header, a number of compressed data blocks in the DEFLATE format, and ends with the CRC32-checksum (in the IEEE format) and number of bytes (modulo 2^32) of the uncompressed data.

The gzip header is purely a set of metadata, and doesn’t have any impact on the decoding of the compressed data other than the fact that DEFLATE-encoded data with a gzip-header is checked using the CRC32 algorithm.

This library is based on the gzip header functionality in the flate2 crate.

Structs

• Crc
  A wrapper struct containing a CRC checksum in the format used by gzip and the amount of bytes input to it mod 2^32.
• CrcReader
  A reader that updates the checksum and counter of a Crc struct when reading from the wrapped reader.
• GzBuilder
  A builder structure to create a new gzip header.
• GzHeader
  A structure representing the raw header of a gzip stream.

Enums

• ExtraFlags
  Valid values for the extra flag in the gzip specification.
• FileSystemType
  An enum describing the different OS types described in the gzip format. See http://www.gzip.org/format.txt (Additionally, the Apple(19) value is defined in the zlib library).

Functions

• read_gz_header
  Try to read a gzip header from the provided reader.