1 LZ4 - Library Files 2 ================================ 3 4 The `/lib` directory contains many files, but depending on project's objectives, 5 not all of them are necessary. 6 7 #### Minimal LZ4 build 8 9 The minimum required is **`lz4.c`** and **`lz4.h`**, 10 which provides the fast compression and decompression algorithm. 11 They generate and decode data using [LZ4 block format]. 12 13 14 #### High Compression variant 15 16 For more compression ratio at the cost of compression speed, 17 the High Compression variant called **lz4hc** is available. 18 Add files **`lz4hc.c`** and **`lz4hc.h`**. 19 The variant still depends on regular `lib/lz4.*` source files. 20 21 22 #### Frame variant, for interoperability 23 24 In order to produce compressed data compatible with `lz4` command line utility, 25 it's necessary to encode lz4-compressed blocks using the [official interoperable frame format]. 26 This format is generated and decoded automatically by the **lz4frame** library. 27 Its public API is described in `lib/lz4frame.h`. 28 In order to work properly, lz4frame needs all other modules present in `/lib`, 29 including, lz4 and lz4hc, and also **xxhash**. 30 So it's necessary to include all `*.c` and `*.h` files present in `/lib`. 31 32 33 #### Advanced / Experimental API 34 35 A complex API defined in `lz4frame_static.h` contains definitions 36 which are not guaranteed to remain stable in future versions. 37 As a consequence, it must be used with static linking ***only***. 38 39 40 #### Windows : using MinGW+MSYS to create DLL 41 42 DLL can be created using MinGW+MSYS with the `make liblz4` command. 43 This command creates `dll\liblz4.dll` and the import library `dll\liblz4.lib`. 44 The import library is only required with Visual C++. 45 The header files `lz4.h`, `lz4hc.h`, `lz4frame.h` and the dynamic library 46 `dll\liblz4.dll` are required to compile a project using gcc/MinGW. 47 The dynamic library has to be added to linking options. 48 It means that if a project that uses LZ4 consists of a single `test-dll.c` 49 file it should be linked with `dll\liblz4.dll`. For example: 50 ``` 51 gcc $(CFLAGS) -Iinclude/ test-dll.c -o test-dll dll\liblz4.dll 52 ``` 53 The compiled executable will require LZ4 DLL which is available at `dll\liblz4.dll`. 54 55 56 #### Miscellaneous 57 58 Other files present in the directory are not source code. There are : 59 60 - `LICENSE` : contains the BSD license text 61 - `Makefile` : `make` script to compile and install lz4 library (static and dynamic) 62 - `liblz4.pc.in` : for `pkg-config` (used in `make install`) 63 - `README.md` : this file 64 65 [official interoperable frame format]: ../doc/lz4_Frame_format.md 66 [LZ4 block format]: ../doc/lz4_Block_format.md 67 68 69 #### License 70 71 All source material within __lib__ directory are BSD 2-Clause licensed. 72 See [LICENSE](LICENSE) for details. 73 The license is also reminded at the top of each source file. 74
