diff options
Diffstat (limited to 'README')
| -rw-r--r-- | README | 41 |
1 files changed, 23 insertions, 18 deletions
@@ -34,6 +34,12 @@ are declared in the file 'lzlib.h'. Usage examples of the library are given in the files 'bbexample.c', 'ffexample.c', and 'minilzip.c' from the source distribution. +As '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 'lzlib.h' +some header that declares the type 'uint8_t'. There are at least four such +headers in C and C++: 'stdint.h', 'cstdint', 'inttypes.h', and '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. @@ -44,18 +50,18 @@ 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 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 '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 +'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. @@ -77,13 +83,13 @@ Lzlib currently implements two variants of the LZMA algorithm: fast (used by 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). @@ -93,11 +99,10 @@ been compressed. Decompressed is used to refer to data which have undergone the process of decompression. -Copyright (C) 2009-2022 Antonio Diaz Diaz. +Copyright (C) 2009-2024 Antonio Diaz Diaz. This file is free documentation: you have unlimited permission to copy, distribute, and modify it. -The file Makefile.in is a data file used by configure to produce the -Makefile. It has the same copyright owner and permissions that configure -itself. +The file Makefile.in is a data file used by configure to produce the Makefile. +It has the same copyright owner and permissions that configure itself. |