Adding upstream version 1.14.
Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
parent
03a9d0ba58
commit
7684d13d23
GPG key ID:
FBB4F0E80A80222F
29 changed files with 744 additions and 652 deletions
251
doc/lzlib.info
251
doc/lzlib.info
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@ -11,7 +11,7 @@ File: lzlib.info, Node: Top, Next: Introduction, Up: (dir)
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Lzlib Manual
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************
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This manual is for Lzlib (version 1.13, 23 January 2022).
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This manual is for Lzlib (version 1.14, 20 January 2024).
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* Menu:
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@ -23,14 +23,14 @@ This manual is for Lzlib (version 1.13, 23 January 2022).
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* Decompression functions:: Descriptions of the decompression functions
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* Error codes:: Meaning of codes returned by functions
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* Error messages:: Error messages corresponding to error codes
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* Invoking minilzip:: Command line interface of the test program
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* Invoking minilzip:: Command-line interface of the test program
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* Data format:: Detailed format of the compressed data
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* Examples:: A small tutorial with examples
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* Problems:: Reporting bugs
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* Concept index:: Index of concepts
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Copyright (C) 2009-2022 Antonio Diaz Diaz.
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Copyright (C) 2009-2024 Antonio Diaz Diaz.
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This manual is free documentation: you have unlimited permission to copy,
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distribute, and modify it.
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@ -76,6 +76,13 @@ library are declared in the file 'lzlib.h'. Usage examples of the library
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are given in the files 'bbexample.c', 'ffexample.c', and 'minilzip.c' from
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the source distribution.
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As 'lzlib.h' can be used by C and C++ programs, it must not impose a
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choice of system headers on the program by including one of them. Therefore
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it is the responsibility of the program using lzlib to include before
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'lzlib.h' some header that declares the type 'uint8_t'. There are at least
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four such headers in C and C++: 'stdint.h', 'cstdint', 'inttypes.h', and
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'cinttypes'.
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All the library functions are thread safe. The library does not install
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any signal handler. The decoder checks the consistency of the compressed
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data, so the library should never crash even in case of corrupted input.
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@ -86,21 +93,21 @@ This interface is safer and less error prone than the traditional zlib
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interface.
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Compression/decompression is done when the read function is called. This
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means the value returned by the position functions will not be updated until
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a read call, even if a lot of data are written. If you want the data to be
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means the value returned by the position functions is not updated until a
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read call, even if a lot of data are written. If you want the data to be
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compressed in advance, just call the read function with a SIZE equal to 0.
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If all the data to be compressed are written in advance, lzlib will
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automatically adjust the header of the compressed data to use the largest
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If all the data to be compressed are written in advance, lzlib
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automatically adjusts the header of the compressed data to use the largest
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dictionary size that does not exceed neither the data size nor the limit
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given to 'LZ_compress_open'. This feature reduces the amount of memory
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needed for decompression and allows minilzip to produce identical compressed
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output as lzip.
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needed for decompression and allows minilzip to produce identical
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compressed output as lzip.
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Lzlib will correctly decompress a data stream which is the concatenation
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of two or more compressed data streams. The result is the concatenation of
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the corresponding decompressed data streams. Integrity testing of
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concatenated compressed data streams is also supported.
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Lzlib correctly decompresses a data stream which is the concatenation of
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two or more compressed data streams. The result is the concatenation of the
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corresponding decompressed data streams. Integrity testing of concatenated
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compressed data streams is also supported.
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Lzlib is able to compress and decompress streams of unlimited size by
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automatically creating multimember output. The members so created are large,
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@ -111,22 +118,22 @@ concrete algorithm; it is more like "any algorithm using the LZMA coding
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scheme". For example, the option '-0' of lzip uses the scheme in almost the
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simplest way possible; issuing the longest match it can find, or a literal
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byte if it can't find a match. Inversely, a much more elaborated way of
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finding coding sequences of minimum size than the one currently used by lzip
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could be developed, and the resulting sequence could also be coded using the
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LZMA coding scheme.
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finding coding sequences of minimum size than the one currently used by
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lzip could be developed, and the resulting sequence could also be coded
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using the LZMA coding scheme.
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Lzlib currently implements two variants of the LZMA algorithm: fast
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(used by option '-0' of minilzip) and normal (used by all other compression
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levels).
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The high compression of LZMA comes from combining two basic, well-proven
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compression ideas: sliding dictionaries (LZ77/78) and markov models (the
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thing used by every compression algorithm that uses a range encoder or
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similar order-0 entropy coder as its last stage) with segregation of
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contexts according to what the bits are used for.
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compression ideas: sliding dictionaries (LZ77) and markov models (the thing
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used by every compression algorithm that uses a range encoder or similar
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order-0 entropy coder as its last stage) with segregation of contexts
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according to what the bits are used for.
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The ideas embodied in lzlib are due to (at least) the following people:
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Abraham Lempel and Jacob Ziv (for the LZ algorithm), Andrey Markov (for the
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Abraham Lempel and Jacob Ziv (for the LZ algorithm), Andrei Markov (for the
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definition of Markov chains), G.N.N. Martin (for the definition of range
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encoding), Igor Pavlov (for putting all the above together in LZMA), and
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Julian Seward (for bzip2's CLI).
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@ -150,7 +157,7 @@ of them are declared in 'lzlib.h'.
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-- Constant: LZ_API_VERSION
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This constant is defined in 'lzlib.h' and works as a version test
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macro. The application should verify at compile time that
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macro. The application should check at compile time that
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LZ_API_VERSION is greater than or equal to the version required by the
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application:
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@ -170,12 +177,13 @@ desire to have certain symbols and prototypes exposed.
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-- Function: int LZ_api_version ( void )
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If LZ_API_VERSION >= 1012, this function is declared in 'lzlib.h' (else
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it doesn't exist). It returns the LZ_API_VERSION of the library object
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code being used. The application should verify at run time that the
|
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code being used. The application should check at run time that the
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value returned by 'LZ_api_version' is greater than or equal to the
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version required by the application. An application may be dinamically
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version required by the application. An application may be dynamically
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linked at run time with a different version of lzlib than the one it
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was compiled for, and this should not break the program as long as the
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library used provides the functionality required by the application.
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was compiled for, and this should not break the application as long as
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the library used provides the functionality required by the
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application.
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#if defined LZ_API_VERSION && LZ_API_VERSION >= 1012
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if( LZ_api_version() < 1012 )
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@ -258,7 +266,7 @@ File: lzlib.info, Node: Compression functions, Next: Decompression functions,
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These are the functions used to compress data. In case of error, all of
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them return -1 or 0, for signed and unsigned return values respectively,
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except 'LZ_compress_open' whose return value must be verified by calling
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except 'LZ_compress_open' whose return value must be checked by calling
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'LZ_compress_errno' before using it.
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-- Function: struct LZ_Encoder * LZ_compress_open ( const int
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@ -269,7 +277,7 @@ except 'LZ_compress_open' whose return value must be verified by calling
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LZ_compress functions, or a null pointer if the encoder could not be
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allocated.
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The returned pointer must be verified by calling 'LZ_compress_errno'
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The returned pointer must be checked by calling 'LZ_compress_errno'
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before using it. If 'LZ_compress_errno' does not return 'LZ_ok', the
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returned pointer must not be used and should be freed with
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'LZ_compress_close' to avoid memory leaks.
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@ -277,8 +285,8 @@ except 'LZ_compress_open' whose return value must be verified by calling
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DICTIONARY_SIZE sets the dictionary size to be used, in bytes. Valid
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values range from 4 KiB to 512 MiB. Note that dictionary sizes are
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quantized. If the size specified does not match one of the valid
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sizes, it will be rounded upwards by adding up to
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(DICTIONARY_SIZE / 8) to it.
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sizes, it is rounded upwards by adding up to (DICTIONARY_SIZE / 8) to
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it.
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MATCH_LEN_LIMIT sets the match length limit in bytes. Valid values
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range from 5 to 273. Larger values usually give better compression
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@ -286,15 +294,14 @@ except 'LZ_compress_open' whose return value must be verified by calling
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If DICTIONARY_SIZE is 65535 and MATCH_LEN_LIMIT is 16, the fast
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variant of LZMA is chosen, which produces identical compressed output
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as 'lzip -0'. (The dictionary size used will be rounded upwards to
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64 KiB).
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as 'lzip -0'. (The dictionary size used is rounded upwards to 64 KiB).
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MEMBER_SIZE sets the member size limit in bytes. Valid values range
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from 4 KiB to 2 PiB. A small member size may degrade compression
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ratio, so use it only when needed. To produce a single-member data
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stream, give MEMBER_SIZE a value larger than the amount of data to be
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produced. Values larger than 2 PiB will be reduced to 2 PiB to prevent
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the uncompressed size of the member from overflowing.
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produced. Values larger than 2 PiB are reduced to 2 PiB to prevent the
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uncompressed size of the member from overflowing.
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-- Function: int LZ_compress_close ( struct LZ_Encoder * const ENCODER )
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Frees all dynamically allocated data structures for this stream. This
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@ -420,7 +427,7 @@ File: lzlib.info, Node: Decompression functions, Next: Error codes, Prev: Com
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These are the functions used to decompress data. In case of error, all of
|
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them return -1 or 0, for signed and unsigned return values respectively,
|
||||
except 'LZ_decompress_open' whose return value must be verified by calling
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except 'LZ_decompress_open' whose return value must be checked by calling
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'LZ_decompress_errno' before using it.
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-- Function: struct LZ_Decoder * LZ_decompress_open ( void )
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@ -429,7 +436,7 @@ except 'LZ_decompress_open' whose return value must be verified by calling
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LZ_decompress functions, or a null pointer if the decoder could not be
|
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allocated.
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|
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The returned pointer must be verified by calling 'LZ_decompress_errno'
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The returned pointer must be checked by calling 'LZ_decompress_errno'
|
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before using it. If 'LZ_decompress_errno' does not return 'LZ_ok', the
|
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returned pointer must not be used and should be freed with
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'LZ_decompress_close' to avoid memory leaks.
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@ -459,13 +466,13 @@ except 'LZ_decompress_open' whose return value must be verified by calling
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Resets the error state of DECODER and enters a search state that lasts
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until a new member header (or the end of the stream) is found. After a
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successful call to 'LZ_decompress_sync_to_member', data written with
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'LZ_decompress_write' will be consumed and 'LZ_decompress_read' will
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return 0 until a header is found.
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'LZ_decompress_write' is consumed and 'LZ_decompress_read' returns 0
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||||
until a header is found.
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This function is useful to discard any data preceding the first member,
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or to discard the rest of the current member, for example in case of a
|
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data error. If the decoder is already at the beginning of a member,
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this function does nothing.
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This function is useful to discard any data preceding the first
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member, or to discard the rest of the current member, for example in
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case of a data error. If the decoder is already at the beginning of a
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member, this function does nothing.
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-- Function: int LZ_decompress_read ( struct LZ_Decoder * const DECODER,
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uint8_t * const BUFFER, const int SIZE )
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@ -571,7 +578,7 @@ File: lzlib.info, Node: Error codes, Next: Error messages, Prev: Decompressio
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Most library functions return -1 to indicate that they have failed. But
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this return value only tells you that an error has occurred. To find out
|
||||
what kind of error it was, you need to verify the error code by calling
|
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what kind of error it was, you need to check the error code by calling
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'LZ_(de)compress_errno'.
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Library functions don't change the value returned by
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@ -639,19 +646,20 @@ File: lzlib.info, Node: Invoking minilzip, Next: Data format, Prev: Error mes
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9 Invoking minilzip
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*******************
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Minilzip is a test program for the compression library lzlib, fully
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compatible with lzip 1.4 or newer.
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Minilzip is a test program for the compression library lzlib, compatible
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with lzip 1.4 or newer.
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Lzip is a lossless data compressor with a user interface similar to the
|
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one of gzip or bzip2. Lzip uses a simplified form of the 'Lempel-Ziv-Markov
|
||||
chain-Algorithm' (LZMA) stream format and provides a 3 factor integrity
|
||||
checking to maximize interoperability and optimize safety. Lzip can compress
|
||||
about as fast as gzip (lzip -0) or compress most files more than bzip2
|
||||
(lzip -9). Decompression speed is intermediate between gzip and bzip2. Lzip
|
||||
is better than gzip and bzip2 from a data recovery perspective. Lzip has
|
||||
been designed, written, and tested with great care to replace gzip and
|
||||
bzip2 as the standard general-purpose compressed format for unix-like
|
||||
systems.
|
||||
chain-Algorithm' (LZMA) stream format to maximize interoperability. The
|
||||
maximum dictionary size is 512 MiB so that any lzip file can be decompressed
|
||||
on 32-bit machines. Lzip provides accurate and robust 3-factor integrity
|
||||
checking. Lzip can compress about as fast as gzip (lzip -0) or compress most
|
||||
files more than bzip2 (lzip -9). Decompression speed is intermediate between
|
||||
gzip and bzip2. Lzip is better than gzip and bzip2 from a data recovery
|
||||
perspective. Lzip has been designed, written, and tested with great care to
|
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replace gzip and bzip2 as the standard general-purpose compressed format for
|
||||
Unix-like systems.
|
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|
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The format for running minilzip is:
|
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|
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|
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@ -660,7 +668,8 @@ The format for running minilzip is:
|
|||
If no file names are specified, minilzip compresses (or decompresses) from
|
||||
standard input to standard output. A hyphen '-' used as a FILE argument
|
||||
means standard input. It can be mixed with other FILES and is read just
|
||||
once, the first time it appears in the command line.
|
||||
once, the first time it appears in the command line. Remember to prepend
|
||||
'./' to any file name beginning with a hyphen, or use '--'.
|
||||
|
||||
minilzip supports the following options: *Note Argument syntax:
|
||||
(arg_parser)Argument syntax.
|
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|
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@ -696,17 +705,18 @@ once, the first time it appears in the command line.
|
|||
members). This option (or '-o') is needed when reading from a named
|
||||
pipe (fifo) or from a device. Use it also to recover as much of the
|
||||
decompressed data as possible when decompressing a corrupt file. '-c'
|
||||
overrides '-o' and '-S'. '-c' has no effect when testing or listing.
|
||||
overrides '-o' and '-S'. '-c' has no effect when testing.
|
||||
|
||||
'-d'
|
||||
'--decompress'
|
||||
Decompress the files specified. If a file does not exist, can't be
|
||||
opened, or the destination file already exists and '--force' has not
|
||||
been specified, minilzip continues decompressing the rest of the files
|
||||
and exits with error status 1. If a file fails to decompress, or is a
|
||||
terminal, minilzip exits immediately with error status 2 without
|
||||
decompressing the rest of the files. A terminal is considered an
|
||||
uncompressed file, and therefore invalid.
|
||||
Decompress the files specified. The integrity of the files specified is
|
||||
checked. If a file does not exist, can't be opened, or the destination
|
||||
file already exists and '--force' has not been specified, minilzip
|
||||
continues decompressing the rest of the files and exits with error
|
||||
status 1. If a file fails to decompress, or is a terminal, minilzip
|
||||
exits immediately with error status 2 without decompressing the rest
|
||||
of the files. A terminal is considered an uncompressed file, and
|
||||
therefore invalid.
|
||||
|
||||
'-f'
|
||||
'--force'
|
||||
|
|
@ -725,17 +735,17 @@ once, the first time it appears in the command line.
|
|||
'--match-length=BYTES'
|
||||
When compressing, set the match length limit in bytes. After a match
|
||||
this long is found, the search is finished. Valid values range from 5
|
||||
to 273. Larger values usually give better compression ratios but longer
|
||||
compression times.
|
||||
to 273. Larger values usually give better compression ratios but
|
||||
longer compression times.
|
||||
|
||||
'-o FILE'
|
||||
'--output=FILE'
|
||||
If '-c' has not been also specified, write the (de)compressed output to
|
||||
FILE; keep input files unchanged. If compressing several files, each
|
||||
file is compressed independently. (The output consists of a sequence of
|
||||
independently compressed members). This option (or '-c') is needed when
|
||||
reading from a named pipe (fifo) or from a device. '-o -' is
|
||||
equivalent to '-c'. '-o' has no effect when testing or listing.
|
||||
If '-c' has not been also specified, write the (de)compressed output
|
||||
to FILE; keep input files unchanged. If compressing several files,
|
||||
each file is compressed independently. (The output consists of a
|
||||
sequence of independently compressed members). This option (or '-c')
|
||||
is needed when reading from a named pipe (fifo) or from a device.
|
||||
'-o -' is equivalent to '-c'. '-o' has no effect when testing.
|
||||
|
||||
When compressing and splitting the output in volumes, FILE is used as
|
||||
a prefix, and several files named 'FILE00001.lz', 'FILE00002.lz', etc,
|
||||
|
|
@ -748,13 +758,13 @@ once, the first time it appears in the command line.
|
|||
'-s BYTES'
|
||||
'--dictionary-size=BYTES'
|
||||
When compressing, set the dictionary size limit in bytes. Minilzip
|
||||
will use for each file the largest dictionary size that does not
|
||||
exceed neither the file size nor this limit. Valid values range from
|
||||
4 KiB to 512 MiB. Values 12 to 29 are interpreted as powers of two,
|
||||
meaning 2^12 to 2^29 bytes. Dictionary sizes are quantized so that
|
||||
they can be coded in just one byte (*note coded-dict-size::). If the
|
||||
size specified does not match one of the valid sizes, it will be
|
||||
rounded upwards by adding up to (BYTES / 8) to it.
|
||||
uses for each file the largest dictionary size that does not exceed
|
||||
neither the file size nor this limit. Valid values range from 4 KiB to
|
||||
512 MiB. Values 12 to 29 are interpreted as powers of two, meaning
|
||||
2^12 to 2^29 bytes. Dictionary sizes are quantized so that they can be
|
||||
coded in just one byte (*note coded-dict-size::). If the size
|
||||
specified does not match one of the valid sizes, it is rounded upwards
|
||||
by adding up to (BYTES / 8) to it.
|
||||
|
||||
For maximum compression you should use a dictionary size limit as large
|
||||
as possible, but keep in mind that the decompression memory requirement
|
||||
|
|
@ -776,7 +786,7 @@ once, the first time it appears in the command line.
|
|||
really performs a trial decompression and throws away the result. Use
|
||||
it together with '-v' to see information about the files. If a file
|
||||
fails the test, does not exist, can't be opened, or is a terminal,
|
||||
minilzip continues checking the rest of the files. A final diagnostic
|
||||
minilzip continues testing the rest of the files. A final diagnostic
|
||||
is shown at verbosity level 1 or higher if any file fails the test
|
||||
when testing multiple files.
|
||||
|
||||
|
|
@ -839,26 +849,29 @@ once, the first time it appears in the command line.
|
|||
defined). *Note Library version::.
|
||||
|
||||
|
||||
Numbers given as arguments to options may be followed by a multiplier
|
||||
and an optional 'B' for "byte".
|
||||
Numbers given as arguments to options may be expressed in decimal,
|
||||
hexadecimal, or octal (using the same syntax as integer constants in C++),
|
||||
and may be followed by a multiplier and an optional 'B' for "byte".
|
||||
|
||||
Table of SI and binary prefixes (unit multipliers):
|
||||
|
||||
Prefix Value | Prefix Value
|
||||
k kilobyte (10^3 = 1000) | Ki kibibyte (2^10 = 1024)
|
||||
M megabyte (10^6) | Mi mebibyte (2^20)
|
||||
G gigabyte (10^9) | Gi gibibyte (2^30)
|
||||
T terabyte (10^12) | Ti tebibyte (2^40)
|
||||
P petabyte (10^15) | Pi pebibyte (2^50)
|
||||
E exabyte (10^18) | Ei exbibyte (2^60)
|
||||
Z zettabyte (10^21) | Zi zebibyte (2^70)
|
||||
Y yottabyte (10^24) | Yi yobibyte (2^80)
|
||||
Prefix Value | Prefix Value
|
||||
k kilobyte (10^3 = 1000) | Ki kibibyte (2^10 = 1024)
|
||||
M megabyte (10^6) | Mi mebibyte (2^20)
|
||||
G gigabyte (10^9) | Gi gibibyte (2^30)
|
||||
T terabyte (10^12) | Ti tebibyte (2^40)
|
||||
P petabyte (10^15) | Pi pebibyte (2^50)
|
||||
E exabyte (10^18) | Ei exbibyte (2^60)
|
||||
Z zettabyte (10^21) | Zi zebibyte (2^70)
|
||||
Y yottabyte (10^24) | Yi yobibyte (2^80)
|
||||
R ronnabyte (10^27) | Ri robibyte (2^90)
|
||||
Q quettabyte (10^30) | Qi quebibyte (2^100)
|
||||
|
||||
|
||||
Exit status: 0 for a normal exit, 1 for environmental problems (file not
|
||||
found, invalid flags, I/O errors, etc), 2 to indicate a corrupt or invalid
|
||||
input file, 3 for an internal consistency error (e.g., bug) which caused
|
||||
minilzip to panic.
|
||||
found, invalid command-line options, I/O errors, etc), 2 to indicate a
|
||||
corrupt or invalid input file, 3 for an internal consistency error (e.g.,
|
||||
bug) which caused minilzip to panic.
|
||||
|
||||
|
||||
File: lzlib.info, Node: Data format, Next: Examples, Prev: Invoking minilzip, Up: Top
|
||||
|
|
@ -886,7 +899,7 @@ when there is no longer anything to take away.
|
|||
represents a variable number of bytes.
|
||||
|
||||
|
||||
Lzip data consist of a series of independent "members" (compressed data
|
||||
Lzip data consist of one or more independent "members" (compressed data
|
||||
sets). The members simply appear one after another in the data stream, with
|
||||
no additional information before, between, or after them. Each member can
|
||||
encode in compressed form up to 16 EiB - 1 byte of uncompressed data. The
|
||||
|
|
@ -933,10 +946,10 @@ size of a multimember data stream is unlimited.
|
|||
|
||||
'Member size (8 bytes)'
|
||||
Total size of the member, including header and trailer. This field acts
|
||||
as a distributed index, allows the verification of stream integrity,
|
||||
and facilitates the safe recovery of undamaged members from
|
||||
multimember files. Member size should be limited to 2 PiB to prevent
|
||||
the data size field from overflowing.
|
||||
as a distributed index, improves the checking of stream integrity, and
|
||||
facilitates the safe recovery of undamaged members from multimember
|
||||
files. Lzip limits the member size to 2 PiB to prevent the data size
|
||||
field from overflowing.
|
||||
|
||||
|
||||
|
||||
|
|
@ -1234,7 +1247,7 @@ int ffrsdecompress( struct LZ_Decoder * const decoder,
|
|||
if( LZ_decompress_errno( decoder ) == LZ_header_error ||
|
||||
LZ_decompress_errno( decoder ) == LZ_data_error )
|
||||
{ LZ_decompress_sync_to_member( decoder ); continue; }
|
||||
else break;
|
||||
break;
|
||||
}
|
||||
len = fwrite( buffer, 1, ret, outfile );
|
||||
if( len < ret ) break;
|
||||
|
|
@ -1293,27 +1306,27 @@ Concept index
|
|||
Tag Table:
|
||||
Node: Top215
|
||||
Node: Introduction1338
|
||||
Node: Library version6413
|
||||
Node: Buffering8957
|
||||
Node: Parameter limits10182
|
||||
Node: Compression functions11136
|
||||
Ref: member_size12946
|
||||
Ref: sync_flush14712
|
||||
Node: Decompression functions19400
|
||||
Node: Error codes26968
|
||||
Node: Error messages29259
|
||||
Node: Invoking minilzip29838
|
||||
Node: Data format39786
|
||||
Ref: coded-dict-size41232
|
||||
Node: Examples42641
|
||||
Node: Buffer compression43602
|
||||
Node: Buffer decompression45122
|
||||
Node: File compression46536
|
||||
Node: File decompression47519
|
||||
Node: File compression mm48523
|
||||
Node: Skipping data errors51552
|
||||
Node: Problems52862
|
||||
Node: Concept index53423
|
||||
Node: Library version6778
|
||||
Node: Buffering9329
|
||||
Node: Parameter limits10554
|
||||
Node: Compression functions11508
|
||||
Ref: member_size13301
|
||||
Ref: sync_flush15063
|
||||
Node: Decompression functions19751
|
||||
Node: Error codes27308
|
||||
Node: Error messages29598
|
||||
Node: Invoking minilzip30177
|
||||
Node: Data format40595
|
||||
Ref: coded-dict-size42041
|
||||
Node: Examples43446
|
||||
Node: Buffer compression44407
|
||||
Node: Buffer decompression45927
|
||||
Node: File compression47341
|
||||
Node: File decompression48324
|
||||
Node: File compression mm49328
|
||||
Node: Skipping data errors52357
|
||||
Node: Problems53662
|
||||
Node: Concept index54223
|
||||
|
||||
End Tag Table
|
||||
|
||||
|
|
|
|||
270
doc/lzlib.texi
270
doc/lzlib.texi
|
|
@ -6,8 +6,8 @@
|
|||
@finalout
|
||||
@c %**end of header
|
||||
|
||||
@set UPDATED 23 January 2022
|
||||
@set VERSION 1.13
|
||||
@set UPDATED 20 January 2024
|
||||
@set VERSION 1.14
|
||||
|
||||
@dircategory Compression
|
||||
@direntry
|
||||
|
|
@ -44,7 +44,7 @@ This manual is for Lzlib (version @value{VERSION}, @value{UPDATED}).
|
|||
* Decompression functions:: Descriptions of the decompression functions
|
||||
* Error codes:: Meaning of codes returned by functions
|
||||
* Error messages:: Error messages corresponding to error codes
|
||||
* Invoking minilzip:: Command line interface of the test program
|
||||
* Invoking minilzip:: Command-line interface of the test program
|
||||
* Data format:: Detailed format of the compressed data
|
||||
* Examples:: A small tutorial with examples
|
||||
* Problems:: Reporting bugs
|
||||
|
|
@ -52,7 +52,7 @@ This manual is for Lzlib (version @value{VERSION}, @value{UPDATED}).
|
|||
@end menu
|
||||
|
||||
@sp 1
|
||||
Copyright @copyright{} 2009-2022 Antonio Diaz Diaz.
|
||||
Copyright @copyright{} 2009-2024 Antonio Diaz Diaz.
|
||||
|
||||
This manual is free documentation: you have unlimited permission to copy,
|
||||
distribute, and modify it.
|
||||
|
|
@ -107,6 +107,13 @@ are declared in the file @samp{lzlib.h}. Usage examples of the library are
|
|||
given in the files @samp{bbexample.c}, @samp{ffexample.c}, and
|
||||
@samp{minilzip.c} from the source distribution.
|
||||
|
||||
As @samp{lzlib.h} can be used by C and C++ programs, it must not impose a
|
||||
choice of system headers on the program by including one of them. Therefore
|
||||
it is the responsibility of the program using lzlib to include before
|
||||
@samp{lzlib.h} some header that declares the type @samp{uint8_t}. There are
|
||||
at least four such headers in C and C++: @samp{stdint.h}, @samp{cstdint},
|
||||
@samp{inttypes.h}, and @samp{cinttypes}.
|
||||
|
||||
All the library functions are thread safe. The library does not install any
|
||||
signal handler. The decoder checks the consistency of the compressed data,
|
||||
so the library should never crash even in case of corrupted input.
|
||||
|
|
@ -117,19 +124,19 @@ This interface is safer and less error prone than the traditional zlib
|
|||
interface.
|
||||
|
||||
Compression/decompression is done when the read function is called. This
|
||||
means the value returned by the position functions will not be updated until
|
||||
a read call, even if a lot of data are written. If you want the data to be
|
||||
means the value returned by the position functions is not updated until a
|
||||
read call, even if a lot of data are written. If you want the data to be
|
||||
compressed in advance, just call the read function with a @var{size} equal
|
||||
to 0.
|
||||
|
||||
If all the data to be compressed are written in advance, lzlib will
|
||||
automatically adjust the header of the compressed data to use the largest
|
||||
dictionary size that does not exceed neither the data size nor the limit
|
||||
given to @samp{LZ_compress_open}. This feature reduces the amount of memory
|
||||
needed for decompression and allows minilzip to produce identical compressed
|
||||
output as lzip.
|
||||
If all the data to be compressed are written in advance, lzlib automatically
|
||||
adjusts the header of the compressed data to use the largest dictionary size
|
||||
that does not exceed neither the data size nor the limit given to
|
||||
@samp{LZ_compress_open}. This feature reduces the amount of memory needed for
|
||||
decompression and allows minilzip to produce identical compressed output as
|
||||
lzip.
|
||||
|
||||
Lzlib will correctly decompress a data stream which is the concatenation of
|
||||
Lzlib correctly decompresses a data stream which is the concatenation of
|
||||
two or more compressed data streams. The result is the concatenation of the
|
||||
corresponding decompressed data streams. Integrity testing of concatenated
|
||||
compressed data streams is also supported.
|
||||
|
|
@ -140,24 +147,24 @@ about @w{2 PiB} each.
|
|||
|
||||
In spite of its name (Lempel-Ziv-Markov chain-Algorithm), LZMA is not a
|
||||
concrete algorithm; it is more like "any algorithm using the LZMA coding
|
||||
scheme". For example, the option @samp{-0} of lzip uses the scheme in almost the
|
||||
simplest way possible; issuing the longest match it can find, or a literal
|
||||
byte if it can't find a match. Inversely, a much more elaborated way of
|
||||
finding coding sequences of minimum size than the one currently used by lzip
|
||||
could be developed, and the resulting sequence could also be coded using the
|
||||
LZMA coding scheme.
|
||||
scheme". For example, the option @option{-0} of lzip uses the scheme in
|
||||
almost the simplest way possible; issuing the longest match it can find, or
|
||||
a literal byte if it can't find a match. Inversely, a much more elaborated
|
||||
way of finding coding sequences of minimum size than the one currently used
|
||||
by lzip could be developed, and the resulting sequence could also be coded
|
||||
using the LZMA coding scheme.
|
||||
|
||||
Lzlib currently implements two variants of the LZMA algorithm: fast (used by
|
||||
option @samp{-0} of minilzip) and normal (used by all other compression levels).
|
||||
option @option{-0} of minilzip) and normal (used by all other compression levels).
|
||||
|
||||
The high compression of LZMA comes from combining two basic, well-proven
|
||||
compression ideas: sliding dictionaries (LZ77/78) and markov models (the
|
||||
thing used by every compression algorithm that uses a range encoder or
|
||||
similar order-0 entropy coder as its last stage) with segregation of
|
||||
contexts according to what the bits are used for.
|
||||
compression ideas: sliding dictionaries (LZ77) and markov models (the thing
|
||||
used by every compression algorithm that uses a range encoder or similar
|
||||
order-0 entropy coder as its last stage) with segregation of contexts
|
||||
according to what the bits are used for.
|
||||
|
||||
The ideas embodied in lzlib are due to (at least) the following people:
|
||||
Abraham Lempel and Jacob Ziv (for the LZ algorithm), Andrey Markov (for the
|
||||
Abraham Lempel and Jacob Ziv (for the LZ algorithm), Andrei Markov (for the
|
||||
definition of Markov chains), G.N.N. Martin (for the definition of range
|
||||
encoding), Igor Pavlov (for putting all the above together in LZMA), and
|
||||
Julian Seward (for bzip2's CLI).
|
||||
|
|
@ -180,7 +187,7 @@ of them are declared in @samp{lzlib.h}.
|
|||
|
||||
@defvr Constant LZ_API_VERSION
|
||||
This constant is defined in @samp{lzlib.h} and works as a version test
|
||||
macro. The application should verify at compile time that LZ_API_VERSION is
|
||||
macro. The application should check at compile time that LZ_API_VERSION is
|
||||
greater than or equal to the version required by the application:
|
||||
|
||||
@example
|
||||
|
|
@ -202,12 +209,12 @@ certain symbols and prototypes exposed.
|
|||
@deftypefun int LZ_api_version ( void )
|
||||
If LZ_API_VERSION >= 1012, this function is declared in @samp{lzlib.h} (else
|
||||
it doesn't exist). It returns the LZ_API_VERSION of the library object code
|
||||
being used. The application should verify at run time that the value
|
||||
being used. The application should check at run time that the value
|
||||
returned by @code{LZ_api_version} is greater than or equal to the version
|
||||
required by the application. An application may be dinamically linked at run
|
||||
required by the application. An application may be dynamically linked at run
|
||||
time with a different version of lzlib than the one it was compiled for, and
|
||||
this should not break the program as long as the library used provides the
|
||||
functionality required by the application.
|
||||
this should not break the application as long as the library used provides
|
||||
the functionality required by the application.
|
||||
|
||||
@example
|
||||
#if defined LZ_API_VERSION && LZ_API_VERSION >= 1012
|
||||
|
|
@ -297,7 +304,7 @@ Returns the largest valid match length limit [273].
|
|||
|
||||
These are the functions used to compress data. In case of error, all of
|
||||
them return -1 or 0, for signed and unsigned return values respectively,
|
||||
except @samp{LZ_compress_open} whose return value must be verified by
|
||||
except @samp{LZ_compress_open} whose return value must be checked by
|
||||
calling @samp{LZ_compress_errno} before using it.
|
||||
|
||||
|
||||
|
|
@ -307,15 +314,15 @@ pointer that can only be used as the @var{encoder} argument for the
|
|||
other LZ_compress functions, or a null pointer if the encoder could not
|
||||
be allocated.
|
||||
|
||||
The returned pointer must be verified by calling
|
||||
@samp{LZ_compress_errno} before using it. If @samp{LZ_compress_errno}
|
||||
does not return @samp{LZ_ok}, the returned pointer must not be used and
|
||||
should be freed with @samp{LZ_compress_close} to avoid memory leaks.
|
||||
The returned pointer must be checked by calling @samp{LZ_compress_errno}
|
||||
before using it. If @samp{LZ_compress_errno} does not return @samp{LZ_ok},
|
||||
the returned pointer must not be used and should be freed with
|
||||
@samp{LZ_compress_close} to avoid memory leaks.
|
||||
|
||||
@var{dictionary_size} sets the dictionary size to be used, in bytes.
|
||||
Valid values range from @w{4 KiB} to @w{512 MiB}. Note that dictionary
|
||||
sizes are quantized. If the size specified does not match one of the
|
||||
valid sizes, it will be rounded upwards by adding up to
|
||||
valid sizes, it is rounded upwards by adding up to
|
||||
@w{(@var{dictionary_size} / 8)} to it.
|
||||
|
||||
@var{match_len_limit} sets the match length limit in bytes. Valid values
|
||||
|
|
@ -324,7 +331,7 @@ but longer compression times.
|
|||
|
||||
If @var{dictionary_size} is 65535 and @var{match_len_limit} is 16, the fast
|
||||
variant of LZMA is chosen, which produces identical compressed output as
|
||||
@w{@samp{lzip -0}}. (The dictionary size used will be rounded upwards to
|
||||
@w{@samp{lzip -0}}. (The dictionary size used is rounded upwards to
|
||||
@w{64 KiB}).
|
||||
|
||||
@anchor{member_size}
|
||||
|
|
@ -332,8 +339,8 @@ variant of LZMA is chosen, which produces identical compressed output as
|
|||
from @w{4 KiB} to @w{2 PiB}. A small member size may degrade compression
|
||||
ratio, so use it only when needed. To produce a single-member data stream,
|
||||
give @var{member_size} a value larger than the amount of data to be
|
||||
produced. Values larger than @w{2 PiB} will be reduced to @w{2 PiB} to
|
||||
prevent the uncompressed size of the member from overflowing.
|
||||
produced. Values larger than @w{2 PiB} are reduced to @w{2 PiB} to prevent
|
||||
the uncompressed size of the member from overflowing.
|
||||
@end deftypefun
|
||||
|
||||
|
||||
|
|
@ -478,20 +485,19 @@ perhaps not yet read.
|
|||
|
||||
These are the functions used to decompress data. In case of error, all of
|
||||
them return -1 or 0, for signed and unsigned return values respectively,
|
||||
except @samp{LZ_decompress_open} whose return value must be verified by
|
||||
except @samp{LZ_decompress_open} whose return value must be checked by
|
||||
calling @samp{LZ_decompress_errno} before using it.
|
||||
|
||||
|
||||
@deftypefun {struct LZ_Decoder *} LZ_decompress_open ( void )
|
||||
Initializes the internal stream state for decompression and returns a
|
||||
pointer that can only be used as the @var{decoder} argument for the
|
||||
other LZ_decompress functions, or a null pointer if the decoder could
|
||||
not be allocated.
|
||||
pointer that can only be used as the @var{decoder} argument for the other
|
||||
LZ_decompress functions, or a null pointer if the decoder could not be
|
||||
allocated.
|
||||
|
||||
The returned pointer must be verified by calling
|
||||
@samp{LZ_decompress_errno} before using it. If
|
||||
@samp{LZ_decompress_errno} does not return @samp{LZ_ok}, the returned
|
||||
pointer must not be used and should be freed with
|
||||
The returned pointer must be checked by calling @samp{LZ_decompress_errno}
|
||||
before using it. If @samp{LZ_decompress_errno} does not return @samp{LZ_ok},
|
||||
the returned pointer must not be used and should be freed with
|
||||
@samp{LZ_decompress_close} to avoid memory leaks.
|
||||
@end deftypefun
|
||||
|
||||
|
|
@ -523,16 +529,16 @@ internal buffers is discarded. Position counters are set to 0.
|
|||
|
||||
|
||||
@deftypefun int LZ_decompress_sync_to_member ( struct LZ_Decoder * const @var{decoder} )
|
||||
Resets the error state of @var{decoder} and enters a search state that
|
||||
lasts until a new member header (or the end of the stream) is found.
|
||||
After a successful call to @samp{LZ_decompress_sync_to_member}, data
|
||||
written with @samp{LZ_decompress_write} will be consumed and
|
||||
@samp{LZ_decompress_read} will return 0 until a header is found.
|
||||
Resets the error state of @var{decoder} and enters a search state that lasts
|
||||
until a new member header (or the end of the stream) is found. After a
|
||||
successful call to @samp{LZ_decompress_sync_to_member}, data written with
|
||||
@samp{LZ_decompress_write} is consumed and @samp{LZ_decompress_read} returns
|
||||
0 until a header is found.
|
||||
|
||||
This function is useful to discard any data preceding the first member,
|
||||
or to discard the rest of the current member, for example in case of a
|
||||
data error. If the decoder is already at the beginning of a member, this
|
||||
function does nothing.
|
||||
This function is useful to discard any data preceding the first member, or
|
||||
to discard the rest of the current member, for example in case of a data
|
||||
error. If the decoder is already at the beginning of a member, this function
|
||||
does nothing.
|
||||
@end deftypefun
|
||||
|
||||
|
||||
|
|
@ -654,7 +660,7 @@ perhaps not yet read.
|
|||
|
||||
Most library functions return -1 to indicate that they have failed. But
|
||||
this return value only tells you that an error has occurred. To find out
|
||||
what kind of error it was, you need to verify the error code by calling
|
||||
what kind of error it was, you need to check the error code by calling
|
||||
@samp{LZ_(de)compress_errno}.
|
||||
|
||||
Library functions don't change the value returned by
|
||||
|
|
@ -728,20 +734,21 @@ The value of @var{lz_errno} normally comes from a call to
|
|||
@cindex invoking
|
||||
@cindex options
|
||||
|
||||
Minilzip is a test program for the compression library lzlib, fully
|
||||
compatible with lzip 1.4 or newer.
|
||||
Minilzip is a test program for the compression library lzlib, compatible
|
||||
with lzip 1.4 or newer.
|
||||
|
||||
@uref{http://www.nongnu.org/lzip/lzip.html,,Lzip}
|
||||
is a lossless data compressor with a user interface similar to the one
|
||||
of gzip or bzip2. Lzip uses a simplified form of the 'Lempel-Ziv-Markov
|
||||
chain-Algorithm' (LZMA) stream format and provides a 3 factor integrity
|
||||
checking to maximize interoperability and optimize safety. Lzip can compress
|
||||
about as fast as gzip @w{(lzip -0)} or compress most files more than bzip2
|
||||
@w{(lzip -9)}. Decompression speed is intermediate between gzip and bzip2.
|
||||
Lzip is better than gzip and bzip2 from a data recovery perspective. Lzip
|
||||
has been designed, written, and tested with great care to replace gzip and
|
||||
bzip2 as the standard general-purpose compressed format for unix-like
|
||||
systems.
|
||||
chain-Algorithm' (LZMA) stream format to maximize interoperability. The
|
||||
maximum dictionary size is 512 MiB so that any lzip file can be decompressed
|
||||
on 32-bit machines. Lzip provides accurate and robust 3-factor integrity
|
||||
checking. Lzip can compress about as fast as gzip @w{(lzip -0)} or compress most
|
||||
files more than bzip2 @w{(lzip -9)}. Decompression speed is intermediate between
|
||||
gzip and bzip2. Lzip is better than gzip and bzip2 from a data recovery
|
||||
perspective. Lzip has been designed, written, and tested with great care to
|
||||
replace gzip and bzip2 as the standard general-purpose compressed format for
|
||||
Unix-like systems.
|
||||
|
||||
@noindent
|
||||
The format for running minilzip is:
|
||||
|
|
@ -754,7 +761,8 @@ minilzip [@var{options}] [@var{files}]
|
|||
If no file names are specified, minilzip compresses (or decompresses) from
|
||||
standard input to standard output. A hyphen @samp{-} used as a @var{file}
|
||||
argument means standard input. It can be mixed with other @var{files} and is
|
||||
read just once, the first time it appears in the command line.
|
||||
read just once, the first time it appears in the command line. Remember to
|
||||
prepend @file{./} to any file name beginning with a hyphen, or use @samp{--}.
|
||||
|
||||
minilzip supports the following
|
||||
@uref{http://www.nongnu.org/arg-parser/manual/arg_parser_manual.html#Argument-syntax,,options}:
|
||||
|
|
@ -791,19 +799,20 @@ compression ratio, so use it only when needed. Valid values range from
|
|||
Compress or decompress to standard output; keep input files unchanged. If
|
||||
compressing several files, each file is compressed independently. (The
|
||||
output consists of a sequence of independently compressed members). This
|
||||
option (or @samp{-o}) is needed when reading from a named pipe (fifo) or
|
||||
option (or @option{-o}) is needed when reading from a named pipe (fifo) or
|
||||
from a device. Use it also to recover as much of the decompressed data as
|
||||
possible when decompressing a corrupt file. @samp{-c} overrides @samp{-o}
|
||||
and @samp{-S}. @samp{-c} has no effect when testing or listing.
|
||||
possible when decompressing a corrupt file. @option{-c} overrides @option{-o}
|
||||
and @option{-S}. @option{-c} has no effect when testing.
|
||||
|
||||
@item -d
|
||||
@itemx --decompress
|
||||
Decompress the files specified. If a file does not exist, can't be opened,
|
||||
or the destination file already exists and @samp{--force} has not been
|
||||
specified, minilzip continues decompressing the rest of the files and exits with
|
||||
error status 1. If a file fails to decompress, or is a terminal, minilzip exits
|
||||
immediately with error status 2 without decompressing the rest of the files.
|
||||
A terminal is considered an uncompressed file, and therefore invalid.
|
||||
Decompress the files specified. The integrity of the files specified is
|
||||
checked. If a file does not exist, can't be opened, or the destination file
|
||||
already exists and @option{--force} has not been specified, minilzip continues
|
||||
decompressing the rest of the files and exits with error status 1. If a file
|
||||
fails to decompress, or is a terminal, minilzip exits immediately with error
|
||||
status 2 without decompressing the rest of the files. A terminal is
|
||||
considered an uncompressed file, and therefore invalid.
|
||||
|
||||
@item -f
|
||||
@itemx --force
|
||||
|
|
@ -820,19 +829,19 @@ Keep (don't delete) input files during compression or decompression.
|
|||
|
||||
@item -m @var{bytes}
|
||||
@itemx --match-length=@var{bytes}
|
||||
When compressing, set the match length limit in bytes. After a match
|
||||
this long is found, the search is finished. Valid values range from 5 to
|
||||
273. Larger values usually give better compression ratios but longer
|
||||
compression times.
|
||||
When compressing, set the match length limit in bytes. After a match this
|
||||
long is found, the search is finished. Valid values range from 5 to 273.
|
||||
Larger values usually give better compression ratios but longer compression
|
||||
times.
|
||||
|
||||
@item -o @var{file}
|
||||
@itemx --output=@var{file}
|
||||
If @samp{-c} has not been also specified, write the (de)compressed output to
|
||||
@var{file}; keep input files unchanged. If compressing several files, each
|
||||
file is compressed independently. (The output consists of a sequence of
|
||||
independently compressed members). This option (or @samp{-c}) is needed when
|
||||
reading from a named pipe (fifo) or from a device. @w{@samp{-o -}} is
|
||||
equivalent to @samp{-c}. @samp{-o} has no effect when testing or listing.
|
||||
If @option{-c} has not been also specified, write the (de)compressed output
|
||||
to @var{file}; keep input files unchanged. If compressing several files,
|
||||
each file is compressed independently. (The output consists of a sequence of
|
||||
independently compressed members). This option (or @option{-c}) is needed
|
||||
when reading from a named pipe (fifo) or from a device. @w{@option{-o -}} is
|
||||
equivalent to @option{-c}. @option{-o} has no effect when testing.
|
||||
|
||||
When compressing and splitting the output in volumes, @var{file} is used as
|
||||
a prefix, and several files named @samp{@var{file}00001.lz},
|
||||
|
|
@ -845,14 +854,14 @@ Quiet operation. Suppress all messages.
|
|||
|
||||
@item -s @var{bytes}
|
||||
@itemx --dictionary-size=@var{bytes}
|
||||
When compressing, set the dictionary size limit in bytes. Minilzip will use
|
||||
for each file the largest dictionary size that does not exceed neither
|
||||
the file size nor this limit. Valid values range from @w{4 KiB} to
|
||||
@w{512 MiB}. Values 12 to 29 are interpreted as powers of two, meaning
|
||||
2^12 to 2^29 bytes. Dictionary sizes are quantized so that they can be
|
||||
coded in just one byte (@pxref{coded-dict-size}). If the size specified
|
||||
does not match one of the valid sizes, it will be rounded upwards by
|
||||
adding up to @w{(@var{bytes} / 8)} to it.
|
||||
When compressing, set the dictionary size limit in bytes. Minilzip uses for
|
||||
each file the largest dictionary size that does not exceed neither the file
|
||||
size nor this limit. Valid values range from @w{4 KiB} to @w{512 MiB}.
|
||||
Values 12 to 29 are interpreted as powers of two, meaning 2^12 to 2^29
|
||||
bytes. Dictionary sizes are quantized so that they can be coded in just one
|
||||
byte (@pxref{coded-dict-size}). If the size specified does not match one of
|
||||
the valid sizes, it is rounded upwards by adding up to @w{(@var{bytes} / 8)}
|
||||
to it.
|
||||
|
||||
For maximum compression you should use a dictionary size limit as large
|
||||
as possible, but keep in mind that the decompression memory requirement
|
||||
|
|
@ -860,7 +869,7 @@ is affected at compression time by the choice of dictionary size limit.
|
|||
|
||||
@item -S @var{bytes}
|
||||
@itemx --volume-size=@var{bytes}
|
||||
When compressing, and @samp{-c} has not been also specified, split the
|
||||
When compressing, and @option{-c} has not been also specified, split the
|
||||
compressed output into several volume files with names
|
||||
@samp{original_name00001.lz}, @samp{original_name00002.lz}, etc, and set the
|
||||
volume size limit to @var{bytes}. Input files are kept unchanged. Each
|
||||
|
|
@ -872,11 +881,11 @@ from @w{100 kB} to @w{4 EiB}.
|
|||
@itemx --test
|
||||
Check integrity of the files specified, but don't decompress them. This
|
||||
really performs a trial decompression and throws away the result. Use it
|
||||
together with @samp{-v} to see information about the files. If a file
|
||||
together with @option{-v} to see information about the files. If a file
|
||||
fails the test, does not exist, can't be opened, or is a terminal, minilzip
|
||||
continues checking the rest of the files. A final diagnostic is shown at
|
||||
verbosity level 1 or higher if any file fails the test when testing
|
||||
multiple files.
|
||||
continues testing the rest of the files. A final diagnostic is shown at
|
||||
verbosity level 1 or higher if any file fails the test when testing multiple
|
||||
files.
|
||||
|
||||
@item -v
|
||||
@itemx --verbose
|
||||
|
|
@ -890,18 +899,18 @@ and trailer contents (CRC, data size, member size).
|
|||
@item -0 .. -9
|
||||
Compression level. Set the compression parameters (dictionary size and
|
||||
match length limit) as shown in the table below. The default compression
|
||||
level is @samp{-6}, equivalent to @w{@samp{-s8MiB -m36}}. Note that
|
||||
@samp{-9} can be much slower than @samp{-0}. These options have no
|
||||
level is @option{-6}, equivalent to @w{@option{-s8MiB -m36}}. Note that
|
||||
@option{-9} can be much slower than @option{-0}. These options have no
|
||||
effect when decompressing or testing.
|
||||
|
||||
The bidimensional parameter space of LZMA can't be mapped to a linear
|
||||
scale optimal for all files. If your files are large, very repetitive,
|
||||
etc, you may need to use the options @samp{--dictionary-size} and
|
||||
@samp{--match-length} directly to achieve optimal performance.
|
||||
The bidimensional parameter space of LZMA can't be mapped to a linear scale
|
||||
optimal for all files. If your files are large, very repetitive, etc, you
|
||||
may need to use the options @option{--dictionary-size} and
|
||||
@option{--match-length} directly to achieve optimal performance.
|
||||
|
||||
If several compression levels or @samp{-s} or @samp{-m} options are
|
||||
given, the last setting is used. For example @w{@samp{-9 -s64MiB}} is
|
||||
equivalent to @w{@samp{-s64MiB -m273}}
|
||||
If several compression levels or @option{-s} or @option{-m} options are
|
||||
given, the last setting is used. For example @w{@option{-9 -s64MiB}} is
|
||||
equivalent to @w{@option{-s64MiB -m273}}
|
||||
|
||||
@multitable {Level} {Dictionary size (-s)} {Match length limit (-m)}
|
||||
@item Level @tab Dictionary size (-s) @tab Match length limit (-m)
|
||||
|
|
@ -942,28 +951,31 @@ version of lzlib being used and the value of LZ_API_VERSION (if defined).
|
|||
|
||||
@end table
|
||||
|
||||
Numbers given as arguments to options may be followed by a multiplier
|
||||
and an optional @samp{B} for "byte".
|
||||
Numbers given as arguments to options may be expressed in decimal,
|
||||
hexadecimal, or octal (using the same syntax as integer constants in C++),
|
||||
and may be followed by a multiplier and an optional @samp{B} for "byte".
|
||||
|
||||
Table of SI and binary prefixes (unit multipliers):
|
||||
|
||||
@multitable {Prefix} {kilobyte (10^3 = 1000)} {|} {Prefix} {kibibyte (2^10 = 1024)}
|
||||
@multitable {Prefix} {kilobyte (10^3 = 1000)} {|} {Prefix} {kibibyte (2^10 = 1024)}
|
||||
@item Prefix @tab Value @tab | @tab Prefix @tab Value
|
||||
@item k @tab kilobyte (10^3 = 1000) @tab | @tab Ki @tab kibibyte (2^10 = 1024)
|
||||
@item M @tab megabyte (10^6) @tab | @tab Mi @tab mebibyte (2^20)
|
||||
@item G @tab gigabyte (10^9) @tab | @tab Gi @tab gibibyte (2^30)
|
||||
@item T @tab terabyte (10^12) @tab | @tab Ti @tab tebibyte (2^40)
|
||||
@item P @tab petabyte (10^15) @tab | @tab Pi @tab pebibyte (2^50)
|
||||
@item E @tab exabyte (10^18) @tab | @tab Ei @tab exbibyte (2^60)
|
||||
@item Z @tab zettabyte (10^21) @tab | @tab Zi @tab zebibyte (2^70)
|
||||
@item Y @tab yottabyte (10^24) @tab | @tab Yi @tab yobibyte (2^80)
|
||||
@item k @tab kilobyte (10^3 = 1000) @tab | @tab Ki @tab kibibyte (2^10 = 1024)
|
||||
@item M @tab megabyte (10^6) @tab | @tab Mi @tab mebibyte (2^20)
|
||||
@item G @tab gigabyte (10^9) @tab | @tab Gi @tab gibibyte (2^30)
|
||||
@item T @tab terabyte (10^12) @tab | @tab Ti @tab tebibyte (2^40)
|
||||
@item P @tab petabyte (10^15) @tab | @tab Pi @tab pebibyte (2^50)
|
||||
@item E @tab exabyte (10^18) @tab | @tab Ei @tab exbibyte (2^60)
|
||||
@item Z @tab zettabyte (10^21) @tab | @tab Zi @tab zebibyte (2^70)
|
||||
@item Y @tab yottabyte (10^24) @tab | @tab Yi @tab yobibyte (2^80)
|
||||
@item R @tab ronnabyte (10^27) @tab | @tab Ri @tab robibyte (2^90)
|
||||
@item Q @tab quettabyte (10^30) @tab | @tab Qi @tab quebibyte (2^100)
|
||||
@end multitable
|
||||
|
||||
@sp 1
|
||||
Exit status: 0 for a normal exit, 1 for environmental problems (file not
|
||||
found, invalid flags, I/O errors, etc), 2 to indicate a corrupt or invalid
|
||||
input file, 3 for an internal consistency error (e.g., bug) which caused
|
||||
minilzip to panic.
|
||||
Exit status: 0 for a normal exit, 1 for environmental problems
|
||||
(file not found, invalid command-line options, I/O errors, etc), 2 to
|
||||
indicate a corrupt or invalid input file, 3 for an internal consistency
|
||||
error (e.g., bug) which caused minilzip to panic.
|
||||
|
||||
|
||||
@node Data format
|
||||
|
|
@ -994,7 +1006,7 @@ represents one byte; a box like this:
|
|||
represents a variable number of bytes.
|
||||
|
||||
@sp 1
|
||||
Lzip data consist of a series of independent "members" (compressed data
|
||||
Lzip data consist of one or more independent "members" (compressed data
|
||||
sets). The members simply appear one after another in the data stream, with
|
||||
no additional information before, between, or after them. Each member can
|
||||
encode in compressed form up to @w{16 EiB - 1 byte} of uncompressed data.
|
||||
|
|
@ -1050,10 +1062,10 @@ Size of the original uncompressed data.
|
|||
|
||||
@item Member size (8 bytes)
|
||||
Total size of the member, including header and trailer. This field acts
|
||||
as a distributed index, allows the verification of stream integrity, and
|
||||
as a distributed index, improves the checking of stream integrity, and
|
||||
facilitates the safe recovery of undamaged members from multimember files.
|
||||
Member size should be limited to @w{2 PiB} to prevent the data size field
|
||||
from overflowing.
|
||||
Lzip limits the member size to @w{2 PiB} to prevent the data size field from
|
||||
overflowing.
|
||||
|
||||
@end table
|
||||
|
||||
|
|
@ -1360,7 +1372,7 @@ int ffrsdecompress( struct LZ_Decoder * const decoder,
|
|||
if( LZ_decompress_errno( decoder ) == LZ_header_error ||
|
||||
LZ_decompress_errno( decoder ) == LZ_data_error )
|
||||
{ LZ_decompress_sync_to_member( decoder ); continue; }
|
||||
else break;
|
||||
break;
|
||||
}
|
||||
len = fwrite( buffer, 1, ret, outfile );
|
||||
if( len < ret ) break;
|
||||
|
|
|
|||
|
|
@ -1,24 +1,25 @@
|
|||
.\" DO NOT MODIFY THIS FILE! It was generated by help2man 1.47.16.
|
||||
.TH MINILZIP "1" "January 2022" "minilzip 1.13" "User Commands"
|
||||
.\" DO NOT MODIFY THIS FILE! It was generated by help2man 1.49.2.
|
||||
.TH MINILZIP "1" "January 2024" "minilzip 1.14" "User Commands"
|
||||
.SH NAME
|
||||
minilzip \- reduces the size of files
|
||||
.SH SYNOPSIS
|
||||
.B minilzip
|
||||
[\fI\,options\/\fR] [\fI\,files\/\fR]
|
||||
.SH DESCRIPTION
|
||||
Minilzip is a test program for the compression library lzlib, fully
|
||||
compatible with lzip 1.4 or newer.
|
||||
Minilzip is a test program for the compression library lzlib, compatible
|
||||
with lzip 1.4 or newer.
|
||||
.PP
|
||||
Lzip is a lossless data compressor with a user interface similar to the one
|
||||
of gzip or bzip2. Lzip uses a simplified form of the 'Lempel\-Ziv\-Markov
|
||||
chain\-Algorithm' (LZMA) stream format and provides a 3 factor integrity
|
||||
checking to maximize interoperability and optimize safety. Lzip can compress
|
||||
about as fast as gzip (lzip \fB\-0\fR) or compress most files more than bzip2
|
||||
(lzip \fB\-9\fR). Decompression speed is intermediate between gzip and bzip2.
|
||||
Lzip is better than gzip and bzip2 from a data recovery perspective. Lzip
|
||||
has been designed, written, and tested with great care to replace gzip and
|
||||
bzip2 as the standard general\-purpose compressed format for unix\-like
|
||||
systems.
|
||||
chain\-Algorithm' (LZMA) stream format to maximize interoperability. The
|
||||
maximum dictionary size is 512 MiB so that any lzip file can be decompressed
|
||||
on 32\-bit machines. Lzip provides accurate and robust 3\-factor integrity
|
||||
checking. Lzip can compress about as fast as gzip (lzip \fB\-0\fR) or compress most
|
||||
files more than bzip2 (lzip \fB\-9\fR). Decompression speed is intermediate between
|
||||
gzip and bzip2. Lzip is better than gzip and bzip2 from a data recovery
|
||||
perspective. Lzip has been designed, written, and tested with great care to
|
||||
replace gzip and bzip2 as the standard general\-purpose compressed format for
|
||||
Unix\-like systems.
|
||||
.SH OPTIONS
|
||||
.TP
|
||||
\fB\-h\fR, \fB\-\-help\fR
|
||||
|
|
@ -37,7 +38,7 @@ set member size limit in bytes
|
|||
write to standard output, keep input files
|
||||
.TP
|
||||
\fB\-d\fR, \fB\-\-decompress\fR
|
||||
decompress
|
||||
decompress, test compressed file integrity
|
||||
.TP
|
||||
\fB\-f\fR, \fB\-\-force\fR
|
||||
overwrite existing output files
|
||||
|
|
@ -88,24 +89,24 @@ If no file names are given, or if a file is '\-', minilzip compresses or
|
|||
decompresses from standard input to standard output.
|
||||
Numbers may be followed by a multiplier: k = kB = 10^3 = 1000,
|
||||
Ki = KiB = 2^10 = 1024, M = 10^6, Mi = 2^20, G = 10^9, Gi = 2^30, etc...
|
||||
Dictionary sizes 12 to 29 are interpreted as powers of two, meaning 2^12
|
||||
to 2^29 bytes.
|
||||
Dictionary sizes 12 to 29 are interpreted as powers of two, meaning 2^12 to
|
||||
2^29 bytes.
|
||||
.PP
|
||||
The bidimensional parameter space of LZMA can't be mapped to a linear
|
||||
scale optimal for all files. If your files are large, very repetitive,
|
||||
etc, you may need to use the options \fB\-\-dictionary\-size\fR and \fB\-\-match\-length\fR
|
||||
directly to achieve optimal performance.
|
||||
The bidimensional parameter space of LZMA can't be mapped to a linear scale
|
||||
optimal for all files. If your files are large, very repetitive, etc, you
|
||||
may need to use the options \fB\-\-dictionary\-size\fR and \fB\-\-match\-length\fR directly
|
||||
to achieve optimal performance.
|
||||
.PP
|
||||
To extract all the files from archive 'foo.tar.lz', use the commands
|
||||
\&'tar \fB\-xf\fR foo.tar.lz' or 'minilzip \fB\-cd\fR foo.tar.lz | tar \fB\-xf\fR \-'.
|
||||
.PP
|
||||
Exit status: 0 for a normal exit, 1 for environmental problems (file
|
||||
not found, invalid flags, I/O errors, etc), 2 to indicate a corrupt or
|
||||
invalid input file, 3 for an internal consistency error (e.g., bug) which
|
||||
caused minilzip to panic.
|
||||
Exit status: 0 for a normal exit, 1 for environmental problems
|
||||
(file not found, invalid command\-line options, I/O errors, etc), 2 to
|
||||
indicate a corrupt or invalid input file, 3 for an internal consistency
|
||||
error (e.g., bug) which caused minilzip to panic.
|
||||
.PP
|
||||
The ideas embodied in lzlib are due to (at least) the following people:
|
||||
Abraham Lempel and Jacob Ziv (for the LZ algorithm), Andrey Markov (for the
|
||||
Abraham Lempel and Jacob Ziv (for the LZ algorithm), Andrei Markov (for the
|
||||
definition of Markov chains), G.N.N. Martin (for the definition of range
|
||||
encoding), Igor Pavlov (for putting all the above together in LZMA), and
|
||||
Julian Seward (for bzip2's CLI).
|
||||
|
|
@ -114,8 +115,9 @@ Report bugs to lzip\-bug@nongnu.org
|
|||
.br
|
||||
Lzlib home page: http://www.nongnu.org/lzip/lzlib.html
|
||||
.SH COPYRIGHT
|
||||
Copyright \(co 2022 Antonio Diaz Diaz.
|
||||
Using lzlib 1.13
|
||||
Copyright \(co 2024 Antonio Diaz Diaz.
|
||||
Using lzlib 1.14
|
||||
Using LZ_API_VERSION = 1014
|
||||
License GPLv2+: GNU GPL version 2 or later <http://gnu.org/licenses/gpl.html>
|
||||
.br
|
||||
This is free software: you are free to change and redistribute it.
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue