4e3accccb2
Dictionaries don't need to be > 4 bytes, they need to be >= 4 bytes. This test was overly conservative. Also removes the test in `LZ4_attach_dictionary()`. |
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|---|---|---|
| .. | ||
| dll/example | ||
| .gitignore | ||
| liblz4.pc.in | ||
| LICENSE | ||
| lz4.c | ||
| lz4.h | ||
| lz4frame_static.h | ||
| lz4frame.c | ||
| lz4frame.h | ||
| lz4hc.c | ||
| lz4hc.h | ||
| Makefile | ||
| README.md | ||
| xxhash.c | ||
| xxhash.h | ||
LZ4 - Library Files
The /lib directory contains many files, but depending on project's objectives,
not all of them are necessary.
Minimal LZ4 build
The minimum required is lz4.c and lz4.h,
which provides the fast compression and decompression algorithm.
They generate and decode data using LZ4 block format.
High Compression variant
For more compression ratio at the cost of compression speed,
the High Compression variant called lz4hc is available.
Add files lz4hc.c and lz4hc.h.
This variant also depends on regular lib/lz4.* source files.
Frame support, for interoperability
In order to produce compressed data compatible with lz4 command line utility,
it's necessary to encode lz4-compressed blocks using the official interoperable frame format.
This format is generated and decoded automatically by the lz4frame library.
Its public API is described in lib/lz4frame.h.
In order to work properly, lz4frame needs all other modules present in /lib,
including, lz4 and lz4hc, and also xxhash.
So it's necessary to include all *.c and *.h files present in /lib.
Advanced / Experimental API
Definitions which are not guaranteed to remain stable in future versions,
are protected behind macros, such as LZ4_STATIC_LINKING_ONLY.
As the name implies, these definitions can only be invoked
in the context of static linking only.
Otherwise, dependent application may fail on API or ABI break in the future.
The associated symbols are also not present in dynamic library by default.
Should they be nonetheless needed, it's possible to force their publication
by using build macro LZ4_PUBLISH_STATIC_FUNCTIONS.
Amalgamation
lz4 code is able to be amalgamated into a single file.
We can combine all source code in lz4_all.c by using following command,
cat lz4.c > lz4_all.c
cat lz4hc.c >> lz4_all.c
cat lz4frame.c >> lz4_all.c
and compile lz4_all.c.
It's necessary to include all *.h files present in /lib together with lz4_all.c.
Windows : using MinGW+MSYS to create DLL
DLL can be created using MinGW+MSYS with the make liblz4 command.
This command creates dll\liblz4.dll and the import library dll\liblz4.lib.
To override the dlltool command when cross-compiling on Linux, just set the DLLTOOL variable. Example of cross compilation on Linux with mingw-w64 64 bits:
make BUILD_STATIC=no CC=x86_64-w64-mingw32-gcc DLLTOOL=x86_64-w64-mingw32-dlltool OS=Windows_NT
The import library is only required with Visual C++.
The header files lz4.h, lz4hc.h, lz4frame.h and the dynamic library
dll\liblz4.dll are required to compile a project using gcc/MinGW.
The dynamic library has to be added to linking options.
It means that if a project that uses LZ4 consists of a single test-dll.c
file it should be linked with dll\liblz4.dll. For example:
$(CC) $(CFLAGS) -Iinclude/ test-dll.c -o test-dll dll\liblz4.dll
The compiled executable will require LZ4 DLL which is available at dll\liblz4.dll.
Miscellaneous
Other files present in the directory are not source code. There are :
LICENSE: contains the BSD license textMakefile:makescript to compile and install lz4 library (static and dynamic)liblz4.pc.in: forpkg-config(used inmake install)README.md: this file
License
All source material within lib directory are BSD 2-Clause licensed. See LICENSE for details. The license is also reminded at the top of each source file.