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Merging upstream version 1.4.

Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
Daniel Baumann 2025-02-17 20:12:24 +01:00
parent 35f10ad47a
commit a31d1b9253
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
21 changed files with 1019 additions and 831 deletions

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@ -6,8 +6,8 @@
@finalout
@c %**end of header
@set UPDATED 25 February 2012
@set VERSION 1.3
@set UPDATED 18 February 2013
@set VERSION 1.4
@dircategory Data Compression
@direntry
@ -45,7 +45,7 @@ This manual is for Clzip (version @value{VERSION}, @value{UPDATED}).
@end menu
@sp 1
Copyright @copyright{} 2010, 2011, 2012 Antonio Diaz Diaz.
Copyright @copyright{} 2010, 2011, 2012, 2013 Antonio Diaz Diaz.
This manual is free documentation: you have unlimited permission
to copy, distribute and modify it.
@ -92,11 +92,15 @@ also split the compressed output in volumes of a given size, even when
reading from standard input. This allows the direct creation of
multivolume compressed tar archives.
The amount of memory required for compression is about 5 MiB plus 1 or 2
times the dictionary size limit (1 if input file size is less than
dictionary size limit, else 2) plus 8 times the dictionary size really
used. The amount of memory required for decompression is only a few tens
of KiB larger than the dictionary size really used.
Clzip is able to compress and decompress streams of unlimited size by
automatically creating multi-member output. The members so created are
large (about 2^60 bytes each).
The amount of memory required for compression is about 1 or 2 times the
dictionary size limit (1 if input file size is less than dictionary size
limit, else 2) plus 9 times the dictionary size really used. The amount
of memory required for decompression is only a few tens of KiB larger
than the dictionary size really used.
Clzip will automatically use the smallest possible dictionary size
without exceeding the given limit. Keep in mind that the decompression
@ -350,6 +354,11 @@ Table of SI and binary prefixes (unit multipliers):
@chapter File Format
@cindex file format
Perfection is reached, not when there is no longer anything to add, but
when there is no longer anything to take away.@*
--- Antoine de Saint-Exupery
@sp 1
In the diagram below, a box like this:
@verbatim
+---+
@ -385,15 +394,16 @@ All multibyte values are stored in little endian order.
A four byte string, identifying the lzip format, with the value "LZIP".
@item VN (version number, 1 byte)
Just in case something needs to be modified in the future. Valid values
are 0 and 1. Version 0 files are deprecated. They can contain only one
member and lack the @samp{Member size} field.
Just in case something needs to be modified in the future. 1 for now.
@item DS (coded dictionary size, 1 byte)
Bits 4-0 contain the base 2 logarithm of the base dictionary size.@*
Bits 7-5 contain the number of "wedges" to substract from the base
dictionary size to obtain the dictionary size. The size of a wedge is
(base dictionary size / 16).@*
Lzip divides the distance between any two powers of 2 into 8 equally
spaced intervals, named "wedges". The dictionary size is calculated by
taking a power of 2 (the base size) and substracting from it a number of
wedges between 0 and 7. The size of a wedge is (base_size / 16).@*
Bits 4-0 contain the base 2 logarithm of the base size (12 to 29).@*
Bits 7-5 contain the number of wedges (0 to 7) to substract from the
base size to obtain the dictionary size.@*
Valid values for dictionary size range from 4KiB to 512MiB.
@item Lzma stream
@ -407,8 +417,9 @@ CRC of the uncompressed original data.
Size of the uncompressed original data.
@item Member size (8 bytes)
Total size of the member, including header and trailer. This facilitates
safe recovery of undamaged members from multi-member files.
Total size of the member, including header and trailer. This field acts
as a distributed index, and facilitates safe recovery of undamaged
members from multi-member files.
@end table