Initial commit
This commit is contained in:
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LZ4 Library
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Copyright (c) 2011-2020, Yann Collet
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All rights reserved.
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Redistribution and use in source and binary forms, with or without modification,
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are permitted provided that the following conditions are met:
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||||
|
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* Redistributions of source code must retain the above copyright notice, this
|
||||
list of conditions and the following disclaimer.
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* Redistributions in binary form must reproduce the above copyright notice, this
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||||
list of conditions and the following disclaimer in the documentation and/or
|
||||
other materials provided with the distribution.
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||||
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||||
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
|
||||
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
|
||||
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
||||
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
|
||||
ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
||||
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
|
||||
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
|
||||
ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
||||
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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LZ4 - Library Files
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================================
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The `/lib` directory contains many files, but depending on project's objectives,
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not all of them are required.
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Limited systems may want to reduce the nb of source files to include
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as a way to reduce binary size and dependencies.
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Capabilities are added at the "level" granularity, detailed below.
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#### Level 1 : Minimal LZ4 build
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The minimum required is **`lz4.c`** and **`lz4.h`**,
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which provides the fast compression and decompression algorithms.
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They generate and decode data using the [LZ4 block format].
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#### Level 2 : High Compression variant
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For more compression ratio at the cost of compression speed,
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the High Compression variant called **lz4hc** is available.
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Add files **`lz4hc.c`** and **`lz4hc.h`**.
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This variant also compresses data using the [LZ4 block format],
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and depends on regular `lib/lz4.*` source files.
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#### Level 3 : Frame support, for interoperability
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In order to produce compressed data compatible with `lz4` command line utility,
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it's necessary to use the [official interoperable frame format].
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This format is generated and decoded automatically by the **lz4frame** library.
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Its public API is described in `lib/lz4frame.h`.
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In order to work properly, lz4frame needs all other modules present in `/lib`,
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including, lz4 and lz4hc, and also **xxhash**.
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So it's necessary to also include `xxhash.c` and `xxhash.h`.
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#### Level 4 : File compression operations
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As a helper around file operations,
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the library has been recently extended with `lz4file.c` and `lz4file.h`
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(still considered experimental at the time of this writing).
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These helpers allow opening, reading, writing, and closing files
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using transparent LZ4 compression / decompression.
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As a consequence, using `lz4file` adds a dependency on `<stdio.h>`.
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`lz4file` relies on `lz4frame` in order to produce compressed data
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conformant to the [LZ4 Frame format] specification.
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Consequently, to enable this capability,
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it's necessary to include all `*.c` and `*.h` files from `lib/` directory.
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#### Advanced / Experimental API
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Definitions which are not guaranteed to remain stable in future versions,
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are protected behind macros, such as `LZ4_STATIC_LINKING_ONLY`.
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As the name suggests, these definitions should only be invoked
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in the context of static linking ***only***.
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Otherwise, dependent application may fail on API or ABI break in the future.
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The associated symbols are also not exposed by the dynamic library by default.
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Should they be nonetheless needed, it's possible to force their publication
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by using build macros `LZ4_PUBLISH_STATIC_FUNCTIONS`
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and `LZ4F_PUBLISH_STATIC_FUNCTIONS`.
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#### Build macros
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The following build macro can be selected to adjust source code behavior at compilation time :
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- `LZ4_FAST_DEC_LOOP` : this triggers a speed optimized decompression loop, more powerful on modern cpus.
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This loop works great on `x86`, `x64` and `aarch64` cpus, and is automatically enabled for them.
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It's also possible to enable or disable it manually, by passing `LZ4_FAST_DEC_LOOP=1` or `0` to the preprocessor.
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For example, with `gcc` : `-DLZ4_FAST_DEC_LOOP=1`,
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and with `make` : `CPPFLAGS+=-DLZ4_FAST_DEC_LOOP=1 make lz4`.
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- `LZ4_DISTANCE_MAX` : control the maximum offset that the compressor will allow.
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Set to 65535 by default, which is the maximum value supported by lz4 format.
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Reducing maximum distance will reduce opportunities for LZ4 to find matches,
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hence will produce a worse compression ratio.
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Setting a smaller max distance could allow compatibility with specific decoders with limited memory budget.
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This build macro only influences the compressed output of the compressor.
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- `LZ4_DISABLE_DEPRECATE_WARNINGS` : invoking a deprecated function will make the compiler generate a warning.
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This is meant to invite users to update their source code.
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Should this be a problem, it's generally possible to make the compiler ignore these warnings,
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for example with `-Wno-deprecated-declarations` on `gcc`,
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or `_CRT_SECURE_NO_WARNINGS` for Visual Studio.
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This build macro offers another project-specific method
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by defining `LZ4_DISABLE_DEPRECATE_WARNINGS` before including the LZ4 header files.
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- `LZ4_FORCE_SW_BITCOUNT` : by default, the compression algorithm tries to determine lengths
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by using bitcount instructions, generally implemented as fast single instructions in many cpus.
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In case the target cpus doesn't support it, or compiler intrinsic doesn't work, or feature bad performance,
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it's possible to use an optimized software path instead.
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This is achieved by setting this build macros.
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In most cases, it's not expected to be necessary,
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but it can be legitimately considered for less common platforms.
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- `LZ4_ALIGN_TEST` : alignment test ensures that the memory area
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passed as argument to become a compression state is suitably aligned.
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This test can be disabled if it proves flaky, by setting this value to 0.
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- `LZ4_USER_MEMORY_FUNCTIONS` : replace calls to `<stdlib.h>`'s `malloc()`, `calloc()` and `free()`
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by user-defined functions, which must be named `LZ4_malloc()`, `LZ4_calloc()` and `LZ4_free()`.
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User functions must be available at link time.
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- `LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION` :
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Remove support of dynamic memory allocation.
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For more details, see description of this macro in `lib/lz4.c`.
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- `LZ4_FREESTANDING` : by setting this build macro to 1,
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LZ4/HC removes dependencies on the C standard library,
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including allocation functions and `memmove()`, `memcpy()`, and `memset()`.
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This build macro is designed to help use LZ4/HC in restricted environments
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(embedded, bootloader, etc).
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For more details, see description of this macro in `lib/lz4.h`.
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- `LZ4_HEAPMODE` : Select how stateless compression functions like `LZ4_compress_default()`
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allocate memory for their hash table,
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in memory stack (0:default, fastest), or in memory heap (1:requires malloc()).
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- `LZ4HC_HEAPMODE` : Select how stateless HC compression functions like `LZ4_compress_HC()`
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allocate memory for their workspace:
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in stack (0), or in heap (1:default).
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Since workspace is rather large, stack can be inconvenient, hence heap mode is recommended.
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- `LZ4F_HEAPMODE` : selects how `LZ4F_compressFrame()` allocates the compression state,
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either on stack (default, value 0) or using heap memory (value 1).
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#### Makefile variables
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The following `Makefile` variables can be selected to alter the profile of produced binaries :
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- `BUILD_SHARED` : generate `libzstd` dynamic library (enabled by default)
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- `BUILD_STATIC` : generate `libzstd` static library (enabled by default)
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#### Amalgamation
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lz4 source code can be amalgamated into a single file.
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One can combine all source code into `lz4_all.c` by using following command:
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```
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cat lz4.c lz4hc.c lz4frame.c > lz4_all.c
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```
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(`cat` file order is important) then compile `lz4_all.c`.
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All `*.h` files present in `/lib` remain necessary to compile `lz4_all.c`.
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#### Windows : using MinGW+MSYS to create DLL
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DLL can be created using MinGW+MSYS with the `make liblz4` command.
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This command creates `dll\liblz4.dll` and the import library `dll\liblz4.lib`.
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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:
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```
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make BUILD_STATIC=no CC=x86_64-w64-mingw32-gcc DLLTOOL=x86_64-w64-mingw32-dlltool OS=Windows_NT
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```
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The import library is only required with Visual C++.
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The header files `lz4.h`, `lz4hc.h`, `lz4frame.h` and the dynamic library
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`dll\liblz4.dll` are required to compile a project using gcc/MinGW.
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The dynamic library has to be added to linking options.
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It means that if a project that uses LZ4 consists of a single `test-dll.c`
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file it should be linked with `dll\liblz4.dll`. For example:
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```
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$(CC) $(CFLAGS) -Iinclude/ test-dll.c -o test-dll dll\liblz4.dll
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```
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The compiled executable will require LZ4 DLL which is available at `dll\liblz4.dll`.
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#### Miscellaneous
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Other files present in the directory are not source code. They are :
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- `LICENSE` : contains the BSD license text
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- `Makefile` : `make` script to compile and install lz4 library (static and dynamic)
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- `liblz4.pc.in` : for `pkg-config` (used in `make install`)
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- `README.md` : this file
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[official interoperable frame format]: ../doc/lz4_Frame_format.md
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[LZ4 Frame format]: ../doc/lz4_Frame_format.md
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[LZ4 block format]: ../doc/lz4_Block_format.md
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#### License
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All source material within __lib__ directory are BSD 2-Clause licensed.
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See [LICENSE](LICENSE) for details.
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The license is also reminded at the top of each source file.
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@@ -0,0 +1,862 @@
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/*
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* LZ4 - Fast LZ compression algorithm
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* Header File
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* Copyright (C) 2011-2020, Yann Collet.
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BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
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|
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Redistribution and use in source and binary forms, with or without
|
||||
modification, are permitted provided that the following conditions are
|
||||
met:
|
||||
|
||||
* Redistributions of source code must retain the above copyright
|
||||
notice, this list of conditions and the following disclaimer.
|
||||
* Redistributions in binary form must reproduce the above
|
||||
copyright notice, this list of conditions and the following disclaimer
|
||||
in the documentation and/or other materials provided with the
|
||||
distribution.
|
||||
|
||||
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
||||
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
||||
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
||||
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
||||
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
||||
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
||||
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
||||
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
||||
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
||||
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
||||
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
||||
|
||||
You can contact the author at :
|
||||
- LZ4 homepage : http://www.lz4.org
|
||||
- LZ4 source repository : https://github.com/lz4/lz4
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||||
*/
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#if defined (__cplusplus)
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extern "C" {
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#endif
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#ifndef LZ4_H_2983827168210
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#define LZ4_H_2983827168210
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/* --- Dependency --- */
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#include <stddef.h> /* size_t */
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/**
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Introduction
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LZ4 is lossless compression algorithm, providing compression speed >500 MB/s per core,
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scalable with multi-cores CPU. It features an extremely fast decoder, with speed in
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multiple GB/s per core, typically reaching RAM speed limits on multi-core systems.
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|
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The LZ4 compression library provides in-memory compression and decompression functions.
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It gives full buffer control to user.
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Compression can be done in:
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- a single step (described as Simple Functions)
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- a single step, reusing a context (described in Advanced Functions)
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- unbounded multiple steps (described as Streaming compression)
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|
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lz4.h generates and decodes LZ4-compressed blocks (doc/lz4_Block_format.md).
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Decompressing such a compressed block requires additional metadata.
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Exact metadata depends on exact decompression function.
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For the typical case of LZ4_decompress_safe(),
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metadata includes block's compressed size, and maximum bound of decompressed size.
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Each application is free to encode and pass such metadata in whichever way it wants.
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lz4.h only handle blocks, it can not generate Frames.
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Blocks are different from Frames (doc/lz4_Frame_format.md).
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Frames bundle both blocks and metadata in a specified manner.
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Embedding metadata is required for compressed data to be self-contained and portable.
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Frame format is delivered through a companion API, declared in lz4frame.h.
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The `lz4` CLI can only manage frames.
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*/
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/*^***************************************************************
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* Export parameters
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*****************************************************************/
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/*
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* LZ4_DLL_EXPORT :
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* Enable exporting of functions when building a Windows DLL
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* LZ4LIB_VISIBILITY :
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* Control library symbols visibility.
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*/
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#ifndef LZ4LIB_VISIBILITY
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# if defined(__GNUC__) && (__GNUC__ >= 4)
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# define LZ4LIB_VISIBILITY __attribute__ ((visibility ("default")))
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# else
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# define LZ4LIB_VISIBILITY
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# endif
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#endif
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#if defined(LZ4_DLL_EXPORT) && (LZ4_DLL_EXPORT==1)
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# define LZ4LIB_API __declspec(dllexport) LZ4LIB_VISIBILITY
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#elif defined(LZ4_DLL_IMPORT) && (LZ4_DLL_IMPORT==1)
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# define LZ4LIB_API __declspec(dllimport) LZ4LIB_VISIBILITY /* It isn't required but allows to generate better code, saving a function pointer load from the IAT and an indirect jump.*/
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#else
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# define LZ4LIB_API LZ4LIB_VISIBILITY
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#endif
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||||
|
||||
/*! LZ4_FREESTANDING :
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* When this macro is set to 1, it enables "freestanding mode" that is
|
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* suitable for typical freestanding environment which doesn't support
|
||||
* standard C library.
|
||||
*
|
||||
* - LZ4_FREESTANDING is a compile-time switch.
|
||||
* - It requires the following macros to be defined:
|
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* LZ4_memcpy, LZ4_memmove, LZ4_memset.
|
||||
* - It only enables LZ4/HC functions which don't use heap.
|
||||
* All LZ4F_* functions are not supported.
|
||||
* - See tests/freestanding.c to check its basic setup.
|
||||
*/
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#if defined(LZ4_FREESTANDING) && (LZ4_FREESTANDING == 1)
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# define LZ4_HEAPMODE 0
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# define LZ4HC_HEAPMODE 0
|
||||
# define LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION 1
|
||||
# if !defined(LZ4_memcpy)
|
||||
# error "LZ4_FREESTANDING requires macro 'LZ4_memcpy'."
|
||||
# endif
|
||||
# if !defined(LZ4_memset)
|
||||
# error "LZ4_FREESTANDING requires macro 'LZ4_memset'."
|
||||
# endif
|
||||
# if !defined(LZ4_memmove)
|
||||
# error "LZ4_FREESTANDING requires macro 'LZ4_memmove'."
|
||||
# endif
|
||||
#elif ! defined(LZ4_FREESTANDING)
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||||
# define LZ4_FREESTANDING 0
|
||||
#endif
|
||||
|
||||
|
||||
/*------ Version ------*/
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||||
#define LZ4_VERSION_MAJOR 1 /* for breaking interface changes */
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||||
#define LZ4_VERSION_MINOR 9 /* for new (non-breaking) interface capabilities */
|
||||
#define LZ4_VERSION_RELEASE 4 /* for tweaks, bug-fixes, or development */
|
||||
|
||||
#define LZ4_VERSION_NUMBER (LZ4_VERSION_MAJOR *100*100 + LZ4_VERSION_MINOR *100 + LZ4_VERSION_RELEASE)
|
||||
|
||||
#define LZ4_LIB_VERSION LZ4_VERSION_MAJOR.LZ4_VERSION_MINOR.LZ4_VERSION_RELEASE
|
||||
#define LZ4_QUOTE(str) #str
|
||||
#define LZ4_EXPAND_AND_QUOTE(str) LZ4_QUOTE(str)
|
||||
#define LZ4_VERSION_STRING LZ4_EXPAND_AND_QUOTE(LZ4_LIB_VERSION) /* requires v1.7.3+ */
|
||||
|
||||
LZ4LIB_API int LZ4_versionNumber (void); /**< library version number; useful to check dll version; requires v1.3.0+ */
|
||||
LZ4LIB_API const char* LZ4_versionString (void); /**< library version string; useful to check dll version; requires v1.7.5+ */
|
||||
|
||||
|
||||
/*-************************************
|
||||
* Tuning parameter
|
||||
**************************************/
|
||||
#define LZ4_MEMORY_USAGE_MIN 10
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||||
#define LZ4_MEMORY_USAGE_DEFAULT 14
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||||
#define LZ4_MEMORY_USAGE_MAX 20
|
||||
|
||||
/*!
|
||||
* LZ4_MEMORY_USAGE :
|
||||
* Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; )
|
||||
* Increasing memory usage improves compression ratio, at the cost of speed.
|
||||
* Reduced memory usage may improve speed at the cost of ratio, thanks to better cache locality.
|
||||
* Default value is 14, for 16KB, which nicely fits into Intel x86 L1 cache
|
||||
*/
|
||||
#ifndef LZ4_MEMORY_USAGE
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# define LZ4_MEMORY_USAGE LZ4_MEMORY_USAGE_DEFAULT
|
||||
#endif
|
||||
|
||||
#if (LZ4_MEMORY_USAGE < LZ4_MEMORY_USAGE_MIN)
|
||||
# error "LZ4_MEMORY_USAGE is too small !"
|
||||
#endif
|
||||
|
||||
#if (LZ4_MEMORY_USAGE > LZ4_MEMORY_USAGE_MAX)
|
||||
# error "LZ4_MEMORY_USAGE is too large !"
|
||||
#endif
|
||||
|
||||
/*-************************************
|
||||
* Simple Functions
|
||||
**************************************/
|
||||
/*! LZ4_compress_default() :
|
||||
* Compresses 'srcSize' bytes from buffer 'src'
|
||||
* into already allocated 'dst' buffer of size 'dstCapacity'.
|
||||
* Compression is guaranteed to succeed if 'dstCapacity' >= LZ4_compressBound(srcSize).
|
||||
* It also runs faster, so it's a recommended setting.
|
||||
* If the function cannot compress 'src' into a more limited 'dst' budget,
|
||||
* compression stops *immediately*, and the function result is zero.
|
||||
* In which case, 'dst' content is undefined (invalid).
|
||||
* srcSize : max supported value is LZ4_MAX_INPUT_SIZE.
|
||||
* dstCapacity : size of buffer 'dst' (which must be already allocated)
|
||||
* @return : the number of bytes written into buffer 'dst' (necessarily <= dstCapacity)
|
||||
* or 0 if compression fails
|
||||
* Note : This function is protected against buffer overflow scenarios (never writes outside 'dst' buffer, nor read outside 'source' buffer).
|
||||
*/
|
||||
LZ4LIB_API int LZ4_compress_default(const char* src, char* dst, int srcSize, int dstCapacity);
|
||||
|
||||
/*! LZ4_decompress_safe() :
|
||||
* @compressedSize : is the exact complete size of the compressed block.
|
||||
* @dstCapacity : is the size of destination buffer (which must be already allocated),
|
||||
* is an upper bound of decompressed size.
|
||||
* @return : the number of bytes decompressed into destination buffer (necessarily <= dstCapacity)
|
||||
* If destination buffer is not large enough, decoding will stop and output an error code (negative value).
|
||||
* If the source stream is detected malformed, the function will stop decoding and return a negative result.
|
||||
* Note 1 : This function is protected against malicious data packets :
|
||||
* it will never writes outside 'dst' buffer, nor read outside 'source' buffer,
|
||||
* even if the compressed block is maliciously modified to order the decoder to do these actions.
|
||||
* In such case, the decoder stops immediately, and considers the compressed block malformed.
|
||||
* Note 2 : compressedSize and dstCapacity must be provided to the function, the compressed block does not contain them.
|
||||
* The implementation is free to send / store / derive this information in whichever way is most beneficial.
|
||||
* If there is a need for a different format which bundles together both compressed data and its metadata, consider looking at lz4frame.h instead.
|
||||
*/
|
||||
LZ4LIB_API int LZ4_decompress_safe (const char* src, char* dst, int compressedSize, int dstCapacity);
|
||||
|
||||
|
||||
/*-************************************
|
||||
* Advanced Functions
|
||||
**************************************/
|
||||
#define LZ4_MAX_INPUT_SIZE 0x7E000000 /* 2 113 929 216 bytes */
|
||||
#define LZ4_COMPRESSBOUND(isize) ((unsigned)(isize) > (unsigned)LZ4_MAX_INPUT_SIZE ? 0 : (isize) + ((isize)/255) + 16)
|
||||
|
||||
/*! LZ4_compressBound() :
|
||||
Provides the maximum size that LZ4 compression may output in a "worst case" scenario (input data not compressible)
|
||||
This function is primarily useful for memory allocation purposes (destination buffer size).
|
||||
Macro LZ4_COMPRESSBOUND() is also provided for compilation-time evaluation (stack memory allocation for example).
|
||||
Note that LZ4_compress_default() compresses faster when dstCapacity is >= LZ4_compressBound(srcSize)
|
||||
inputSize : max supported value is LZ4_MAX_INPUT_SIZE
|
||||
return : maximum output size in a "worst case" scenario
|
||||
or 0, if input size is incorrect (too large or negative)
|
||||
*/
|
||||
LZ4LIB_API int LZ4_compressBound(int inputSize);
|
||||
|
||||
/*! LZ4_compress_fast() :
|
||||
Same as LZ4_compress_default(), but allows selection of "acceleration" factor.
|
||||
The larger the acceleration value, the faster the algorithm, but also the lesser the compression.
|
||||
It's a trade-off. It can be fine tuned, with each successive value providing roughly +~3% to speed.
|
||||
An acceleration value of "1" is the same as regular LZ4_compress_default()
|
||||
Values <= 0 will be replaced by LZ4_ACCELERATION_DEFAULT (currently == 1, see lz4.c).
|
||||
Values > LZ4_ACCELERATION_MAX will be replaced by LZ4_ACCELERATION_MAX (currently == 65537, see lz4.c).
|
||||
*/
|
||||
LZ4LIB_API int LZ4_compress_fast (const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
|
||||
|
||||
|
||||
/*! LZ4_compress_fast_extState() :
|
||||
* Same as LZ4_compress_fast(), using an externally allocated memory space for its state.
|
||||
* Use LZ4_sizeofState() to know how much memory must be allocated,
|
||||
* and allocate it on 8-bytes boundaries (using `malloc()` typically).
|
||||
* Then, provide this buffer as `void* state` to compression function.
|
||||
*/
|
||||
LZ4LIB_API int LZ4_sizeofState(void);
|
||||
LZ4LIB_API int LZ4_compress_fast_extState (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
|
||||
|
||||
|
||||
/*! LZ4_compress_destSize() :
|
||||
* Reverse the logic : compresses as much data as possible from 'src' buffer
|
||||
* into already allocated buffer 'dst', of size >= 'targetDestSize'.
|
||||
* This function either compresses the entire 'src' content into 'dst' if it's large enough,
|
||||
* or fill 'dst' buffer completely with as much data as possible from 'src'.
|
||||
* note: acceleration parameter is fixed to "default".
|
||||
*
|
||||
* *srcSizePtr : will be modified to indicate how many bytes where read from 'src' to fill 'dst'.
|
||||
* New value is necessarily <= input value.
|
||||
* @return : Nb bytes written into 'dst' (necessarily <= targetDestSize)
|
||||
* or 0 if compression fails.
|
||||
*
|
||||
* Note : from v1.8.2 to v1.9.1, this function had a bug (fixed un v1.9.2+):
|
||||
* the produced compressed content could, in specific circumstances,
|
||||
* require to be decompressed into a destination buffer larger
|
||||
* by at least 1 byte than the content to decompress.
|
||||
* If an application uses `LZ4_compress_destSize()`,
|
||||
* it's highly recommended to update liblz4 to v1.9.2 or better.
|
||||
* If this can't be done or ensured,
|
||||
* the receiving decompression function should provide
|
||||
* a dstCapacity which is > decompressedSize, by at least 1 byte.
|
||||
* See https://github.com/lz4/lz4/issues/859 for details
|
||||
*/
|
||||
LZ4LIB_API int LZ4_compress_destSize (const char* src, char* dst, int* srcSizePtr, int targetDstSize);
|
||||
|
||||
|
||||
/*! LZ4_decompress_safe_partial() :
|
||||
* Decompress an LZ4 compressed block, of size 'srcSize' at position 'src',
|
||||
* into destination buffer 'dst' of size 'dstCapacity'.
|
||||
* Up to 'targetOutputSize' bytes will be decoded.
|
||||
* The function stops decoding on reaching this objective.
|
||||
* This can be useful to boost performance
|
||||
* whenever only the beginning of a block is required.
|
||||
*
|
||||
* @return : the number of bytes decoded in `dst` (necessarily <= targetOutputSize)
|
||||
* If source stream is detected malformed, function returns a negative result.
|
||||
*
|
||||
* Note 1 : @return can be < targetOutputSize, if compressed block contains less data.
|
||||
*
|
||||
* Note 2 : targetOutputSize must be <= dstCapacity
|
||||
*
|
||||
* Note 3 : this function effectively stops decoding on reaching targetOutputSize,
|
||||
* so dstCapacity is kind of redundant.
|
||||
* This is because in older versions of this function,
|
||||
* decoding operation would still write complete sequences.
|
||||
* Therefore, there was no guarantee that it would stop writing at exactly targetOutputSize,
|
||||
* it could write more bytes, though only up to dstCapacity.
|
||||
* Some "margin" used to be required for this operation to work properly.
|
||||
* Thankfully, this is no longer necessary.
|
||||
* The function nonetheless keeps the same signature, in an effort to preserve API compatibility.
|
||||
*
|
||||
* Note 4 : If srcSize is the exact size of the block,
|
||||
* then targetOutputSize can be any value,
|
||||
* including larger than the block's decompressed size.
|
||||
* The function will, at most, generate block's decompressed size.
|
||||
*
|
||||
* Note 5 : If srcSize is _larger_ than block's compressed size,
|
||||
* then targetOutputSize **MUST** be <= block's decompressed size.
|
||||
* Otherwise, *silent corruption will occur*.
|
||||
*/
|
||||
LZ4LIB_API int LZ4_decompress_safe_partial (const char* src, char* dst, int srcSize, int targetOutputSize, int dstCapacity);
|
||||
|
||||
|
||||
/*-*********************************************
|
||||
* Streaming Compression Functions
|
||||
***********************************************/
|
||||
typedef union LZ4_stream_u LZ4_stream_t; /* incomplete type (defined later) */
|
||||
|
||||
/**
|
||||
Note about RC_INVOKED
|
||||
|
||||
- RC_INVOKED is predefined symbol of rc.exe (the resource compiler which is part of MSVC/Visual Studio).
|
||||
https://docs.microsoft.com/en-us/windows/win32/menurc/predefined-macros
|
||||
|
||||
- Since rc.exe is a legacy compiler, it truncates long symbol (> 30 chars)
|
||||
and reports warning "RC4011: identifier truncated".
|
||||
|
||||
- To eliminate the warning, we surround long preprocessor symbol with
|
||||
"#if !defined(RC_INVOKED) ... #endif" block that means
|
||||
"skip this block when rc.exe is trying to read it".
|
||||
*/
|
||||
#if !defined(RC_INVOKED) /* https://docs.microsoft.com/en-us/windows/win32/menurc/predefined-macros */
|
||||
#if !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION)
|
||||
LZ4LIB_API LZ4_stream_t* LZ4_createStream(void);
|
||||
LZ4LIB_API int LZ4_freeStream (LZ4_stream_t* streamPtr);
|
||||
#endif /* !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION) */
|
||||
#endif
|
||||
|
||||
/*! LZ4_resetStream_fast() : v1.9.0+
|
||||
* Use this to prepare an LZ4_stream_t for a new chain of dependent blocks
|
||||
* (e.g., LZ4_compress_fast_continue()).
|
||||
*
|
||||
* An LZ4_stream_t must be initialized once before usage.
|
||||
* This is automatically done when created by LZ4_createStream().
|
||||
* However, should the LZ4_stream_t be simply declared on stack (for example),
|
||||
* it's necessary to initialize it first, using LZ4_initStream().
|
||||
*
|
||||
* After init, start any new stream with LZ4_resetStream_fast().
|
||||
* A same LZ4_stream_t can be re-used multiple times consecutively
|
||||
* and compress multiple streams,
|
||||
* provided that it starts each new stream with LZ4_resetStream_fast().
|
||||
*
|
||||
* LZ4_resetStream_fast() is much faster than LZ4_initStream(),
|
||||
* but is not compatible with memory regions containing garbage data.
|
||||
*
|
||||
* Note: it's only useful to call LZ4_resetStream_fast()
|
||||
* in the context of streaming compression.
|
||||
* The *extState* functions perform their own resets.
|
||||
* Invoking LZ4_resetStream_fast() before is redundant, and even counterproductive.
|
||||
*/
|
||||
LZ4LIB_API void LZ4_resetStream_fast (LZ4_stream_t* streamPtr);
|
||||
|
||||
/*! LZ4_loadDict() :
|
||||
* Use this function to reference a static dictionary into LZ4_stream_t.
|
||||
* The dictionary must remain available during compression.
|
||||
* LZ4_loadDict() triggers a reset, so any previous data will be forgotten.
|
||||
* The same dictionary will have to be loaded on decompression side for successful decoding.
|
||||
* Dictionary are useful for better compression of small data (KB range).
|
||||
* While LZ4 accept any input as dictionary,
|
||||
* results are generally better when using Zstandard's Dictionary Builder.
|
||||
* Loading a size of 0 is allowed, and is the same as reset.
|
||||
* @return : loaded dictionary size, in bytes (necessarily <= 64 KB)
|
||||
*/
|
||||
LZ4LIB_API int LZ4_loadDict (LZ4_stream_t* streamPtr, const char* dictionary, int dictSize);
|
||||
|
||||
/*! LZ4_compress_fast_continue() :
|
||||
* Compress 'src' content using data from previously compressed blocks, for better compression ratio.
|
||||
* 'dst' buffer must be already allocated.
|
||||
* If dstCapacity >= LZ4_compressBound(srcSize), compression is guaranteed to succeed, and runs faster.
|
||||
*
|
||||
* @return : size of compressed block
|
||||
* or 0 if there is an error (typically, cannot fit into 'dst').
|
||||
*
|
||||
* Note 1 : Each invocation to LZ4_compress_fast_continue() generates a new block.
|
||||
* Each block has precise boundaries.
|
||||
* Each block must be decompressed separately, calling LZ4_decompress_*() with relevant metadata.
|
||||
* It's not possible to append blocks together and expect a single invocation of LZ4_decompress_*() to decompress them together.
|
||||
*
|
||||
* Note 2 : The previous 64KB of source data is __assumed__ to remain present, unmodified, at same address in memory !
|
||||
*
|
||||
* Note 3 : When input is structured as a double-buffer, each buffer can have any size, including < 64 KB.
|
||||
* Make sure that buffers are separated, by at least one byte.
|
||||
* This construction ensures that each block only depends on previous block.
|
||||
*
|
||||
* Note 4 : If input buffer is a ring-buffer, it can have any size, including < 64 KB.
|
||||
*
|
||||
* Note 5 : After an error, the stream status is undefined (invalid), it can only be reset or freed.
|
||||
*/
|
||||
LZ4LIB_API int LZ4_compress_fast_continue (LZ4_stream_t* streamPtr, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
|
||||
|
||||
/*! LZ4_saveDict() :
|
||||
* If last 64KB data cannot be guaranteed to remain available at its current memory location,
|
||||
* save it into a safer place (char* safeBuffer).
|
||||
* This is schematically equivalent to a memcpy() followed by LZ4_loadDict(),
|
||||
* but is much faster, because LZ4_saveDict() doesn't need to rebuild tables.
|
||||
* @return : saved dictionary size in bytes (necessarily <= maxDictSize), or 0 if error.
|
||||
*/
|
||||
LZ4LIB_API int LZ4_saveDict (LZ4_stream_t* streamPtr, char* safeBuffer, int maxDictSize);
|
||||
|
||||
|
||||
/*-**********************************************
|
||||
* Streaming Decompression Functions
|
||||
* Bufferless synchronous API
|
||||
************************************************/
|
||||
typedef union LZ4_streamDecode_u LZ4_streamDecode_t; /* tracking context */
|
||||
|
||||
/*! LZ4_createStreamDecode() and LZ4_freeStreamDecode() :
|
||||
* creation / destruction of streaming decompression tracking context.
|
||||
* A tracking context can be re-used multiple times.
|
||||
*/
|
||||
#if !defined(RC_INVOKED) /* https://docs.microsoft.com/en-us/windows/win32/menurc/predefined-macros */
|
||||
#if !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION)
|
||||
LZ4LIB_API LZ4_streamDecode_t* LZ4_createStreamDecode(void);
|
||||
LZ4LIB_API int LZ4_freeStreamDecode (LZ4_streamDecode_t* LZ4_stream);
|
||||
#endif /* !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION) */
|
||||
#endif
|
||||
|
||||
/*! LZ4_setStreamDecode() :
|
||||
* An LZ4_streamDecode_t context can be allocated once and re-used multiple times.
|
||||
* Use this function to start decompression of a new stream of blocks.
|
||||
* A dictionary can optionally be set. Use NULL or size 0 for a reset order.
|
||||
* Dictionary is presumed stable : it must remain accessible and unmodified during next decompression.
|
||||
* @return : 1 if OK, 0 if error
|
||||
*/
|
||||
LZ4LIB_API int LZ4_setStreamDecode (LZ4_streamDecode_t* LZ4_streamDecode, const char* dictionary, int dictSize);
|
||||
|
||||
/*! LZ4_decoderRingBufferSize() : v1.8.2+
|
||||
* Note : in a ring buffer scenario (optional),
|
||||
* blocks are presumed decompressed next to each other
|
||||
* up to the moment there is not enough remaining space for next block (remainingSize < maxBlockSize),
|
||||
* at which stage it resumes from beginning of ring buffer.
|
||||
* When setting such a ring buffer for streaming decompression,
|
||||
* provides the minimum size of this ring buffer
|
||||
* to be compatible with any source respecting maxBlockSize condition.
|
||||
* @return : minimum ring buffer size,
|
||||
* or 0 if there is an error (invalid maxBlockSize).
|
||||
*/
|
||||
LZ4LIB_API int LZ4_decoderRingBufferSize(int maxBlockSize);
|
||||
#define LZ4_DECODER_RING_BUFFER_SIZE(maxBlockSize) (65536 + 14 + (maxBlockSize)) /* for static allocation; maxBlockSize presumed valid */
|
||||
|
||||
/*! LZ4_decompress_safe_continue() :
|
||||
* This decoding function allows decompression of consecutive blocks in "streaming" mode.
|
||||
* The difference with the usual independent blocks is that
|
||||
* new blocks are allowed to find references into former blocks.
|
||||
* A block is an unsplittable entity, and must be presented entirely to the decompression function.
|
||||
* LZ4_decompress_safe_continue() only accepts one block at a time.
|
||||
* It's modeled after `LZ4_decompress_safe()` and behaves similarly.
|
||||
*
|
||||
* @LZ4_streamDecode : decompression state, tracking the position in memory of past data
|
||||
* @compressedSize : exact complete size of one compressed block.
|
||||
* @dstCapacity : size of destination buffer (which must be already allocated),
|
||||
* must be an upper bound of decompressed size.
|
||||
* @return : number of bytes decompressed into destination buffer (necessarily <= dstCapacity)
|
||||
* If destination buffer is not large enough, decoding will stop and output an error code (negative value).
|
||||
* If the source stream is detected malformed, the function will stop decoding and return a negative result.
|
||||
*
|
||||
* The last 64KB of previously decoded data *must* remain available and unmodified
|
||||
* at the memory position where they were previously decoded.
|
||||
* If less than 64KB of data has been decoded, all the data must be present.
|
||||
*
|
||||
* Special : if decompression side sets a ring buffer, it must respect one of the following conditions :
|
||||
* - Decompression buffer size is _at least_ LZ4_decoderRingBufferSize(maxBlockSize).
|
||||
* maxBlockSize is the maximum size of any single block. It can have any value > 16 bytes.
|
||||
* In which case, encoding and decoding buffers do not need to be synchronized.
|
||||
* Actually, data can be produced by any source compliant with LZ4 format specification, and respecting maxBlockSize.
|
||||
* - Synchronized mode :
|
||||
* Decompression buffer size is _exactly_ the same as compression buffer size,
|
||||
* and follows exactly same update rule (block boundaries at same positions),
|
||||
* and decoding function is provided with exact decompressed size of each block (exception for last block of the stream),
|
||||
* _then_ decoding & encoding ring buffer can have any size, including small ones ( < 64 KB).
|
||||
* - Decompression buffer is larger than encoding buffer, by a minimum of maxBlockSize more bytes.
|
||||
* In which case, encoding and decoding buffers do not need to be synchronized,
|
||||
* and encoding ring buffer can have any size, including small ones ( < 64 KB).
|
||||
*
|
||||
* Whenever these conditions are not possible,
|
||||
* save the last 64KB of decoded data into a safe buffer where it can't be modified during decompression,
|
||||
* then indicate where this data is saved using LZ4_setStreamDecode(), before decompressing next block.
|
||||
*/
|
||||
LZ4LIB_API int
|
||||
LZ4_decompress_safe_continue (LZ4_streamDecode_t* LZ4_streamDecode,
|
||||
const char* src, char* dst,
|
||||
int srcSize, int dstCapacity);
|
||||
|
||||
|
||||
/*! LZ4_decompress_safe_usingDict() :
|
||||
* Works the same as
|
||||
* a combination of LZ4_setStreamDecode() followed by LZ4_decompress_safe_continue()
|
||||
* However, it's stateless: it doesn't need any LZ4_streamDecode_t state.
|
||||
* Dictionary is presumed stable : it must remain accessible and unmodified during decompression.
|
||||
* Performance tip : Decompression speed can be substantially increased
|
||||
* when dst == dictStart + dictSize.
|
||||
*/
|
||||
LZ4LIB_API int
|
||||
LZ4_decompress_safe_usingDict(const char* src, char* dst,
|
||||
int srcSize, int dstCapacity,
|
||||
const char* dictStart, int dictSize);
|
||||
|
||||
/*! LZ4_decompress_safe_partial_usingDict() :
|
||||
* Behaves the same as LZ4_decompress_safe_partial()
|
||||
* with the added ability to specify a memory segment for past data.
|
||||
* Performance tip : Decompression speed can be substantially increased
|
||||
* when dst == dictStart + dictSize.
|
||||
*/
|
||||
LZ4LIB_API int
|
||||
LZ4_decompress_safe_partial_usingDict(const char* src, char* dst,
|
||||
int compressedSize,
|
||||
int targetOutputSize, int maxOutputSize,
|
||||
const char* dictStart, int dictSize);
|
||||
|
||||
#endif /* LZ4_H_2983827168210 */
|
||||
|
||||
|
||||
/*^*************************************
|
||||
* !!!!!! STATIC LINKING ONLY !!!!!!
|
||||
***************************************/
|
||||
|
||||
/*-****************************************************************************
|
||||
* Experimental section
|
||||
*
|
||||
* Symbols declared in this section must be considered unstable. Their
|
||||
* signatures or semantics may change, or they may be removed altogether in the
|
||||
* future. They are therefore only safe to depend on when the caller is
|
||||
* statically linked against the library.
|
||||
*
|
||||
* To protect against unsafe usage, not only are the declarations guarded,
|
||||
* the definitions are hidden by default
|
||||
* when building LZ4 as a shared/dynamic library.
|
||||
*
|
||||
* In order to access these declarations,
|
||||
* define LZ4_STATIC_LINKING_ONLY in your application
|
||||
* before including LZ4's headers.
|
||||
*
|
||||
* In order to make their implementations accessible dynamically, you must
|
||||
* define LZ4_PUBLISH_STATIC_FUNCTIONS when building the LZ4 library.
|
||||
******************************************************************************/
|
||||
|
||||
#ifdef LZ4_STATIC_LINKING_ONLY
|
||||
|
||||
#ifndef LZ4_STATIC_3504398509
|
||||
#define LZ4_STATIC_3504398509
|
||||
|
||||
#ifdef LZ4_PUBLISH_STATIC_FUNCTIONS
|
||||
#define LZ4LIB_STATIC_API LZ4LIB_API
|
||||
#else
|
||||
#define LZ4LIB_STATIC_API
|
||||
#endif
|
||||
|
||||
|
||||
/*! LZ4_compress_fast_extState_fastReset() :
|
||||
* A variant of LZ4_compress_fast_extState().
|
||||
*
|
||||
* Using this variant avoids an expensive initialization step.
|
||||
* It is only safe to call if the state buffer is known to be correctly initialized already
|
||||
* (see above comment on LZ4_resetStream_fast() for a definition of "correctly initialized").
|
||||
* From a high level, the difference is that
|
||||
* this function initializes the provided state with a call to something like LZ4_resetStream_fast()
|
||||
* while LZ4_compress_fast_extState() starts with a call to LZ4_resetStream().
|
||||
*/
|
||||
LZ4LIB_STATIC_API int LZ4_compress_fast_extState_fastReset (void* state, const char* src, char* dst, int srcSize, int dstCapacity, int acceleration);
|
||||
|
||||
/*! LZ4_attach_dictionary() :
|
||||
* This is an experimental API that allows
|
||||
* efficient use of a static dictionary many times.
|
||||
*
|
||||
* Rather than re-loading the dictionary buffer into a working context before
|
||||
* each compression, or copying a pre-loaded dictionary's LZ4_stream_t into a
|
||||
* working LZ4_stream_t, this function introduces a no-copy setup mechanism,
|
||||
* in which the working stream references the dictionary stream in-place.
|
||||
*
|
||||
* Several assumptions are made about the state of the dictionary stream.
|
||||
* Currently, only streams which have been prepared by LZ4_loadDict() should
|
||||
* be expected to work.
|
||||
*
|
||||
* Alternatively, the provided dictionaryStream may be NULL,
|
||||
* in which case any existing dictionary stream is unset.
|
||||
*
|
||||
* If a dictionary is provided, it replaces any pre-existing stream history.
|
||||
* The dictionary contents are the only history that can be referenced and
|
||||
* logically immediately precede the data compressed in the first subsequent
|
||||
* compression call.
|
||||
*
|
||||
* The dictionary will only remain attached to the working stream through the
|
||||
* first compression call, at the end of which it is cleared. The dictionary
|
||||
* stream (and source buffer) must remain in-place / accessible / unchanged
|
||||
* through the completion of the first compression call on the stream.
|
||||
*/
|
||||
LZ4LIB_STATIC_API void
|
||||
LZ4_attach_dictionary(LZ4_stream_t* workingStream,
|
||||
const LZ4_stream_t* dictionaryStream);
|
||||
|
||||
|
||||
/*! In-place compression and decompression
|
||||
*
|
||||
* It's possible to have input and output sharing the same buffer,
|
||||
* for highly constrained memory environments.
|
||||
* In both cases, it requires input to lay at the end of the buffer,
|
||||
* and decompression to start at beginning of the buffer.
|
||||
* Buffer size must feature some margin, hence be larger than final size.
|
||||
*
|
||||
* |<------------------------buffer--------------------------------->|
|
||||
* |<-----------compressed data--------->|
|
||||
* |<-----------decompressed size------------------>|
|
||||
* |<----margin---->|
|
||||
*
|
||||
* This technique is more useful for decompression,
|
||||
* since decompressed size is typically larger,
|
||||
* and margin is short.
|
||||
*
|
||||
* In-place decompression will work inside any buffer
|
||||
* which size is >= LZ4_DECOMPRESS_INPLACE_BUFFER_SIZE(decompressedSize).
|
||||
* This presumes that decompressedSize > compressedSize.
|
||||
* Otherwise, it means compression actually expanded data,
|
||||
* and it would be more efficient to store such data with a flag indicating it's not compressed.
|
||||
* This can happen when data is not compressible (already compressed, or encrypted).
|
||||
*
|
||||
* For in-place compression, margin is larger, as it must be able to cope with both
|
||||
* history preservation, requiring input data to remain unmodified up to LZ4_DISTANCE_MAX,
|
||||
* and data expansion, which can happen when input is not compressible.
|
||||
* As a consequence, buffer size requirements are much higher,
|
||||
* and memory savings offered by in-place compression are more limited.
|
||||
*
|
||||
* There are ways to limit this cost for compression :
|
||||
* - Reduce history size, by modifying LZ4_DISTANCE_MAX.
|
||||
* Note that it is a compile-time constant, so all compressions will apply this limit.
|
||||
* Lower values will reduce compression ratio, except when input_size < LZ4_DISTANCE_MAX,
|
||||
* so it's a reasonable trick when inputs are known to be small.
|
||||
* - Require the compressor to deliver a "maximum compressed size".
|
||||
* This is the `dstCapacity` parameter in `LZ4_compress*()`.
|
||||
* When this size is < LZ4_COMPRESSBOUND(inputSize), then compression can fail,
|
||||
* in which case, the return code will be 0 (zero).
|
||||
* The caller must be ready for these cases to happen,
|
||||
* and typically design a backup scheme to send data uncompressed.
|
||||
* The combination of both techniques can significantly reduce
|
||||
* the amount of margin required for in-place compression.
|
||||
*
|
||||
* In-place compression can work in any buffer
|
||||
* which size is >= (maxCompressedSize)
|
||||
* with maxCompressedSize == LZ4_COMPRESSBOUND(srcSize) for guaranteed compression success.
|
||||
* LZ4_COMPRESS_INPLACE_BUFFER_SIZE() depends on both maxCompressedSize and LZ4_DISTANCE_MAX,
|
||||
* so it's possible to reduce memory requirements by playing with them.
|
||||
*/
|
||||
|
||||
#define LZ4_DECOMPRESS_INPLACE_MARGIN(compressedSize) (((compressedSize) >> 8) + 32)
|
||||
#define LZ4_DECOMPRESS_INPLACE_BUFFER_SIZE(decompressedSize) ((decompressedSize) + LZ4_DECOMPRESS_INPLACE_MARGIN(decompressedSize)) /**< note: presumes that compressedSize < decompressedSize. note2: margin is overestimated a bit, since it could use compressedSize instead */
|
||||
|
||||
#ifndef LZ4_DISTANCE_MAX /* history window size; can be user-defined at compile time */
|
||||
# define LZ4_DISTANCE_MAX 65535 /* set to maximum value by default */
|
||||
#endif
|
||||
|
||||
#define LZ4_COMPRESS_INPLACE_MARGIN (LZ4_DISTANCE_MAX + 32) /* LZ4_DISTANCE_MAX can be safely replaced by srcSize when it's smaller */
|
||||
#define LZ4_COMPRESS_INPLACE_BUFFER_SIZE(maxCompressedSize) ((maxCompressedSize) + LZ4_COMPRESS_INPLACE_MARGIN) /**< maxCompressedSize is generally LZ4_COMPRESSBOUND(inputSize), but can be set to any lower value, with the risk that compression can fail (return code 0(zero)) */
|
||||
|
||||
#endif /* LZ4_STATIC_3504398509 */
|
||||
#endif /* LZ4_STATIC_LINKING_ONLY */
|
||||
|
||||
|
||||
|
||||
#ifndef LZ4_H_98237428734687
|
||||
#define LZ4_H_98237428734687
|
||||
|
||||
/*-************************************************************
|
||||
* Private Definitions
|
||||
**************************************************************
|
||||
* Do not use these definitions directly.
|
||||
* They are only exposed to allow static allocation of `LZ4_stream_t` and `LZ4_streamDecode_t`.
|
||||
* Accessing members will expose user code to API and/or ABI break in future versions of the library.
|
||||
**************************************************************/
|
||||
#define LZ4_HASHLOG (LZ4_MEMORY_USAGE-2)
|
||||
#define LZ4_HASHTABLESIZE (1 << LZ4_MEMORY_USAGE)
|
||||
#define LZ4_HASH_SIZE_U32 (1 << LZ4_HASHLOG) /* required as macro for static allocation */
|
||||
|
||||
#if defined(__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
|
||||
# include <stdint.h>
|
||||
typedef int8_t LZ4_i8;
|
||||
typedef uint8_t LZ4_byte;
|
||||
typedef uint16_t LZ4_u16;
|
||||
typedef uint32_t LZ4_u32;
|
||||
#else
|
||||
typedef signed char LZ4_i8;
|
||||
typedef unsigned char LZ4_byte;
|
||||
typedef unsigned short LZ4_u16;
|
||||
typedef unsigned int LZ4_u32;
|
||||
#endif
|
||||
|
||||
/*! LZ4_stream_t :
|
||||
* Never ever use below internal definitions directly !
|
||||
* These definitions are not API/ABI safe, and may change in future versions.
|
||||
* If you need static allocation, declare or allocate an LZ4_stream_t object.
|
||||
**/
|
||||
|
||||
typedef struct LZ4_stream_t_internal LZ4_stream_t_internal;
|
||||
struct LZ4_stream_t_internal {
|
||||
LZ4_u32 hashTable[LZ4_HASH_SIZE_U32];
|
||||
const LZ4_byte* dictionary;
|
||||
const LZ4_stream_t_internal* dictCtx;
|
||||
LZ4_u32 currentOffset;
|
||||
LZ4_u32 tableType;
|
||||
LZ4_u32 dictSize;
|
||||
/* Implicit padding to ensure structure is aligned */
|
||||
};
|
||||
|
||||
#define LZ4_STREAM_MINSIZE ((1UL << LZ4_MEMORY_USAGE) + 32) /* static size, for inter-version compatibility */
|
||||
union LZ4_stream_u {
|
||||
char minStateSize[LZ4_STREAM_MINSIZE];
|
||||
LZ4_stream_t_internal internal_donotuse;
|
||||
}; /* previously typedef'd to LZ4_stream_t */
|
||||
|
||||
|
||||
/*! LZ4_initStream() : v1.9.0+
|
||||
* An LZ4_stream_t structure must be initialized at least once.
|
||||
* This is automatically done when invoking LZ4_createStream(),
|
||||
* but it's not when the structure is simply declared on stack (for example).
|
||||
*
|
||||
* Use LZ4_initStream() to properly initialize a newly declared LZ4_stream_t.
|
||||
* It can also initialize any arbitrary buffer of sufficient size,
|
||||
* and will @return a pointer of proper type upon initialization.
|
||||
*
|
||||
* Note : initialization fails if size and alignment conditions are not respected.
|
||||
* In which case, the function will @return NULL.
|
||||
* Note2: An LZ4_stream_t structure guarantees correct alignment and size.
|
||||
* Note3: Before v1.9.0, use LZ4_resetStream() instead
|
||||
**/
|
||||
LZ4LIB_API LZ4_stream_t* LZ4_initStream (void* buffer, size_t size);
|
||||
|
||||
|
||||
/*! LZ4_streamDecode_t :
|
||||
* Never ever use below internal definitions directly !
|
||||
* These definitions are not API/ABI safe, and may change in future versions.
|
||||
* If you need static allocation, declare or allocate an LZ4_streamDecode_t object.
|
||||
**/
|
||||
typedef struct {
|
||||
const LZ4_byte* externalDict;
|
||||
const LZ4_byte* prefixEnd;
|
||||
size_t extDictSize;
|
||||
size_t prefixSize;
|
||||
} LZ4_streamDecode_t_internal;
|
||||
|
||||
#define LZ4_STREAMDECODE_MINSIZE 32
|
||||
union LZ4_streamDecode_u {
|
||||
char minStateSize[LZ4_STREAMDECODE_MINSIZE];
|
||||
LZ4_streamDecode_t_internal internal_donotuse;
|
||||
} ; /* previously typedef'd to LZ4_streamDecode_t */
|
||||
|
||||
|
||||
|
||||
/*-************************************
|
||||
* Obsolete Functions
|
||||
**************************************/
|
||||
|
||||
/*! Deprecation warnings
|
||||
*
|
||||
* Deprecated functions make the compiler generate a warning when invoked.
|
||||
* This is meant to invite users to update their source code.
|
||||
* Should deprecation warnings be a problem, it is generally possible to disable them,
|
||||
* typically with -Wno-deprecated-declarations for gcc
|
||||
* or _CRT_SECURE_NO_WARNINGS in Visual.
|
||||
*
|
||||
* Another method is to define LZ4_DISABLE_DEPRECATE_WARNINGS
|
||||
* before including the header file.
|
||||
*/
|
||||
#ifdef LZ4_DISABLE_DEPRECATE_WARNINGS
|
||||
# define LZ4_DEPRECATED(message) /* disable deprecation warnings */
|
||||
#else
|
||||
# if defined (__cplusplus) && (__cplusplus >= 201402) /* C++14 or greater */
|
||||
# define LZ4_DEPRECATED(message) [[deprecated(message)]]
|
||||
# elif defined(_MSC_VER)
|
||||
# define LZ4_DEPRECATED(message) __declspec(deprecated(message))
|
||||
# elif defined(__clang__) || (defined(__GNUC__) && (__GNUC__ * 10 + __GNUC_MINOR__ >= 45))
|
||||
# define LZ4_DEPRECATED(message) __attribute__((deprecated(message)))
|
||||
# elif defined(__GNUC__) && (__GNUC__ * 10 + __GNUC_MINOR__ >= 31)
|
||||
# define LZ4_DEPRECATED(message) __attribute__((deprecated))
|
||||
# else
|
||||
# pragma message("WARNING: LZ4_DEPRECATED needs custom implementation for this compiler")
|
||||
# define LZ4_DEPRECATED(message) /* disabled */
|
||||
# endif
|
||||
#endif /* LZ4_DISABLE_DEPRECATE_WARNINGS */
|
||||
|
||||
/*! Obsolete compression functions (since v1.7.3) */
|
||||
LZ4_DEPRECATED("use LZ4_compress_default() instead") LZ4LIB_API int LZ4_compress (const char* src, char* dest, int srcSize);
|
||||
LZ4_DEPRECATED("use LZ4_compress_default() instead") LZ4LIB_API int LZ4_compress_limitedOutput (const char* src, char* dest, int srcSize, int maxOutputSize);
|
||||
LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") LZ4LIB_API int LZ4_compress_withState (void* state, const char* source, char* dest, int inputSize);
|
||||
LZ4_DEPRECATED("use LZ4_compress_fast_extState() instead") LZ4LIB_API int LZ4_compress_limitedOutput_withState (void* state, const char* source, char* dest, int inputSize, int maxOutputSize);
|
||||
LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") LZ4LIB_API int LZ4_compress_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize);
|
||||
LZ4_DEPRECATED("use LZ4_compress_fast_continue() instead") LZ4LIB_API int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_streamPtr, const char* source, char* dest, int inputSize, int maxOutputSize);
|
||||
|
||||
/*! Obsolete decompression functions (since v1.8.0) */
|
||||
LZ4_DEPRECATED("use LZ4_decompress_fast() instead") LZ4LIB_API int LZ4_uncompress (const char* source, char* dest, int outputSize);
|
||||
LZ4_DEPRECATED("use LZ4_decompress_safe() instead") LZ4LIB_API int LZ4_uncompress_unknownOutputSize (const char* source, char* dest, int isize, int maxOutputSize);
|
||||
|
||||
/* Obsolete streaming functions (since v1.7.0)
|
||||
* degraded functionality; do not use!
|
||||
*
|
||||
* In order to perform streaming compression, these functions depended on data
|
||||
* that is no longer tracked in the state. They have been preserved as well as
|
||||
* possible: using them will still produce a correct output. However, they don't
|
||||
* actually retain any history between compression calls. The compression ratio
|
||||
* achieved will therefore be no better than compressing each chunk
|
||||
* independently.
|
||||
*/
|
||||
LZ4_DEPRECATED("Use LZ4_createStream() instead") LZ4LIB_API void* LZ4_create (char* inputBuffer);
|
||||
LZ4_DEPRECATED("Use LZ4_createStream() instead") LZ4LIB_API int LZ4_sizeofStreamState(void);
|
||||
LZ4_DEPRECATED("Use LZ4_resetStream() instead") LZ4LIB_API int LZ4_resetStreamState(void* state, char* inputBuffer);
|
||||
LZ4_DEPRECATED("Use LZ4_saveDict() instead") LZ4LIB_API char* LZ4_slideInputBuffer (void* state);
|
||||
|
||||
/*! Obsolete streaming decoding functions (since v1.7.0) */
|
||||
LZ4_DEPRECATED("use LZ4_decompress_safe_usingDict() instead") LZ4LIB_API int LZ4_decompress_safe_withPrefix64k (const char* src, char* dst, int compressedSize, int maxDstSize);
|
||||
LZ4_DEPRECATED("use LZ4_decompress_fast_usingDict() instead") LZ4LIB_API int LZ4_decompress_fast_withPrefix64k (const char* src, char* dst, int originalSize);
|
||||
|
||||
/*! Obsolete LZ4_decompress_fast variants (since v1.9.0) :
|
||||
* These functions used to be faster than LZ4_decompress_safe(),
|
||||
* but this is no longer the case. They are now slower.
|
||||
* This is because LZ4_decompress_fast() doesn't know the input size,
|
||||
* and therefore must progress more cautiously into the input buffer to not read beyond the end of block.
|
||||
* On top of that `LZ4_decompress_fast()` is not protected vs malformed or malicious inputs, making it a security liability.
|
||||
* As a consequence, LZ4_decompress_fast() is strongly discouraged, and deprecated.
|
||||
*
|
||||
* The last remaining LZ4_decompress_fast() specificity is that
|
||||
* it can decompress a block without knowing its compressed size.
|
||||
* Such functionality can be achieved in a more secure manner
|
||||
* by employing LZ4_decompress_safe_partial().
|
||||
*
|
||||
* Parameters:
|
||||
* originalSize : is the uncompressed size to regenerate.
|
||||
* `dst` must be already allocated, its size must be >= 'originalSize' bytes.
|
||||
* @return : number of bytes read from source buffer (== compressed size).
|
||||
* The function expects to finish at block's end exactly.
|
||||
* If the source stream is detected malformed, the function stops decoding and returns a negative result.
|
||||
* note : LZ4_decompress_fast*() requires originalSize. Thanks to this information, it never writes past the output buffer.
|
||||
* However, since it doesn't know its 'src' size, it may read an unknown amount of input, past input buffer bounds.
|
||||
* Also, since match offsets are not validated, match reads from 'src' may underflow too.
|
||||
* These issues never happen if input (compressed) data is correct.
|
||||
* But they may happen if input data is invalid (error or intentional tampering).
|
||||
* As a consequence, use these functions in trusted environments with trusted data **only**.
|
||||
*/
|
||||
LZ4_DEPRECATED("This function is deprecated and unsafe. Consider using LZ4_decompress_safe() instead")
|
||||
LZ4LIB_API int LZ4_decompress_fast (const char* src, char* dst, int originalSize);
|
||||
LZ4_DEPRECATED("This function is deprecated and unsafe. Consider using LZ4_decompress_safe_continue() instead")
|
||||
LZ4LIB_API int LZ4_decompress_fast_continue (LZ4_streamDecode_t* LZ4_streamDecode, const char* src, char* dst, int originalSize);
|
||||
LZ4_DEPRECATED("This function is deprecated and unsafe. Consider using LZ4_decompress_safe_usingDict() instead")
|
||||
LZ4LIB_API int LZ4_decompress_fast_usingDict (const char* src, char* dst, int originalSize, const char* dictStart, int dictSize);
|
||||
|
||||
/*! LZ4_resetStream() :
|
||||
* An LZ4_stream_t structure must be initialized at least once.
|
||||
* This is done with LZ4_initStream(), or LZ4_resetStream().
|
||||
* Consider switching to LZ4_initStream(),
|
||||
* invoking LZ4_resetStream() will trigger deprecation warnings in the future.
|
||||
*/
|
||||
LZ4LIB_API void LZ4_resetStream (LZ4_stream_t* streamPtr);
|
||||
|
||||
|
||||
#endif /* LZ4_H_98237428734687 */
|
||||
|
||||
|
||||
#if defined (__cplusplus)
|
||||
}
|
||||
#endif
|
||||
+1637
File diff suppressed because it is too large
Load Diff
+413
@@ -0,0 +1,413 @@
|
||||
/*
|
||||
LZ4 HC - High Compression Mode of LZ4
|
||||
Header File
|
||||
Copyright (C) 2011-2020, Yann Collet.
|
||||
BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
|
||||
|
||||
Redistribution and use in source and binary forms, with or without
|
||||
modification, are permitted provided that the following conditions are
|
||||
met:
|
||||
|
||||
* Redistributions of source code must retain the above copyright
|
||||
notice, this list of conditions and the following disclaimer.
|
||||
* Redistributions in binary form must reproduce the above
|
||||
copyright notice, this list of conditions and the following disclaimer
|
||||
in the documentation and/or other materials provided with the
|
||||
distribution.
|
||||
|
||||
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
||||
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
||||
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
||||
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
||||
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
||||
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
||||
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
||||
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
||||
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
||||
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
||||
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
||||
|
||||
You can contact the author at :
|
||||
- LZ4 source repository : https://github.com/lz4/lz4
|
||||
- LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c
|
||||
*/
|
||||
#ifndef LZ4_HC_H_19834876238432
|
||||
#define LZ4_HC_H_19834876238432
|
||||
|
||||
#if defined (__cplusplus)
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
/* --- Dependency --- */
|
||||
/* note : lz4hc requires lz4.h/lz4.c for compilation */
|
||||
#include "lz4.h" /* stddef, LZ4LIB_API, LZ4_DEPRECATED */
|
||||
|
||||
|
||||
/* --- Useful constants --- */
|
||||
#define LZ4HC_CLEVEL_MIN 3
|
||||
#define LZ4HC_CLEVEL_DEFAULT 9
|
||||
#define LZ4HC_CLEVEL_OPT_MIN 10
|
||||
#define LZ4HC_CLEVEL_MAX 12
|
||||
|
||||
|
||||
/*-************************************
|
||||
* Block Compression
|
||||
**************************************/
|
||||
/*! LZ4_compress_HC() :
|
||||
* Compress data from `src` into `dst`, using the powerful but slower "HC" algorithm.
|
||||
* `dst` must be already allocated.
|
||||
* Compression is guaranteed to succeed if `dstCapacity >= LZ4_compressBound(srcSize)` (see "lz4.h")
|
||||
* Max supported `srcSize` value is LZ4_MAX_INPUT_SIZE (see "lz4.h")
|
||||
* `compressionLevel` : any value between 1 and LZ4HC_CLEVEL_MAX will work.
|
||||
* Values > LZ4HC_CLEVEL_MAX behave the same as LZ4HC_CLEVEL_MAX.
|
||||
* @return : the number of bytes written into 'dst'
|
||||
* or 0 if compression fails.
|
||||
*/
|
||||
LZ4LIB_API int LZ4_compress_HC (const char* src, char* dst, int srcSize, int dstCapacity, int compressionLevel);
|
||||
|
||||
|
||||
/* Note :
|
||||
* Decompression functions are provided within "lz4.h" (BSD license)
|
||||
*/
|
||||
|
||||
|
||||
/*! LZ4_compress_HC_extStateHC() :
|
||||
* Same as LZ4_compress_HC(), but using an externally allocated memory segment for `state`.
|
||||
* `state` size is provided by LZ4_sizeofStateHC().
|
||||
* Memory segment must be aligned on 8-bytes boundaries (which a normal malloc() should do properly).
|
||||
*/
|
||||
LZ4LIB_API int LZ4_sizeofStateHC(void);
|
||||
LZ4LIB_API int LZ4_compress_HC_extStateHC(void* stateHC, const char* src, char* dst, int srcSize, int maxDstSize, int compressionLevel);
|
||||
|
||||
|
||||
/*! LZ4_compress_HC_destSize() : v1.9.0+
|
||||
* Will compress as much data as possible from `src`
|
||||
* to fit into `targetDstSize` budget.
|
||||
* Result is provided in 2 parts :
|
||||
* @return : the number of bytes written into 'dst' (necessarily <= targetDstSize)
|
||||
* or 0 if compression fails.
|
||||
* `srcSizePtr` : on success, *srcSizePtr is updated to indicate how much bytes were read from `src`
|
||||
*/
|
||||
LZ4LIB_API int LZ4_compress_HC_destSize(void* stateHC,
|
||||
const char* src, char* dst,
|
||||
int* srcSizePtr, int targetDstSize,
|
||||
int compressionLevel);
|
||||
|
||||
|
||||
/*-************************************
|
||||
* Streaming Compression
|
||||
* Bufferless synchronous API
|
||||
**************************************/
|
||||
typedef union LZ4_streamHC_u LZ4_streamHC_t; /* incomplete type (defined later) */
|
||||
|
||||
/*! LZ4_createStreamHC() and LZ4_freeStreamHC() :
|
||||
* These functions create and release memory for LZ4 HC streaming state.
|
||||
* Newly created states are automatically initialized.
|
||||
* A same state can be used multiple times consecutively,
|
||||
* starting with LZ4_resetStreamHC_fast() to start a new stream of blocks.
|
||||
*/
|
||||
LZ4LIB_API LZ4_streamHC_t* LZ4_createStreamHC(void);
|
||||
LZ4LIB_API int LZ4_freeStreamHC (LZ4_streamHC_t* streamHCPtr);
|
||||
|
||||
/*
|
||||
These functions compress data in successive blocks of any size,
|
||||
using previous blocks as dictionary, to improve compression ratio.
|
||||
One key assumption is that previous blocks (up to 64 KB) remain read-accessible while compressing next blocks.
|
||||
There is an exception for ring buffers, which can be smaller than 64 KB.
|
||||
Ring-buffer scenario is automatically detected and handled within LZ4_compress_HC_continue().
|
||||
|
||||
Before starting compression, state must be allocated and properly initialized.
|
||||
LZ4_createStreamHC() does both, though compression level is set to LZ4HC_CLEVEL_DEFAULT.
|
||||
|
||||
Selecting the compression level can be done with LZ4_resetStreamHC_fast() (starts a new stream)
|
||||
or LZ4_setCompressionLevel() (anytime, between blocks in the same stream) (experimental).
|
||||
LZ4_resetStreamHC_fast() only works on states which have been properly initialized at least once,
|
||||
which is automatically the case when state is created using LZ4_createStreamHC().
|
||||
|
||||
After reset, a first "fictional block" can be designated as initial dictionary,
|
||||
using LZ4_loadDictHC() (Optional).
|
||||
|
||||
Invoke LZ4_compress_HC_continue() to compress each successive block.
|
||||
The number of blocks is unlimited.
|
||||
Previous input blocks, including initial dictionary when present,
|
||||
must remain accessible and unmodified during compression.
|
||||
|
||||
It's allowed to update compression level anytime between blocks,
|
||||
using LZ4_setCompressionLevel() (experimental).
|
||||
|
||||
'dst' buffer should be sized to handle worst case scenarios
|
||||
(see LZ4_compressBound(), it ensures compression success).
|
||||
In case of failure, the API does not guarantee recovery,
|
||||
so the state _must_ be reset.
|
||||
To ensure compression success
|
||||
whenever `dst` buffer size cannot be made >= LZ4_compressBound(),
|
||||
consider using LZ4_compress_HC_continue_destSize().
|
||||
|
||||
Whenever previous input blocks can't be preserved unmodified in-place during compression of next blocks,
|
||||
it's possible to copy the last blocks into a more stable memory space, using LZ4_saveDictHC().
|
||||
Return value of LZ4_saveDictHC() is the size of dictionary effectively saved into 'safeBuffer' (<= 64 KB)
|
||||
|
||||
After completing a streaming compression,
|
||||
it's possible to start a new stream of blocks, using the same LZ4_streamHC_t state,
|
||||
just by resetting it, using LZ4_resetStreamHC_fast().
|
||||
*/
|
||||
|
||||
LZ4LIB_API void LZ4_resetStreamHC_fast(LZ4_streamHC_t* streamHCPtr, int compressionLevel); /* v1.9.0+ */
|
||||
LZ4LIB_API int LZ4_loadDictHC (LZ4_streamHC_t* streamHCPtr, const char* dictionary, int dictSize);
|
||||
|
||||
LZ4LIB_API int LZ4_compress_HC_continue (LZ4_streamHC_t* streamHCPtr,
|
||||
const char* src, char* dst,
|
||||
int srcSize, int maxDstSize);
|
||||
|
||||
/*! LZ4_compress_HC_continue_destSize() : v1.9.0+
|
||||
* Similar to LZ4_compress_HC_continue(),
|
||||
* but will read as much data as possible from `src`
|
||||
* to fit into `targetDstSize` budget.
|
||||
* Result is provided into 2 parts :
|
||||
* @return : the number of bytes written into 'dst' (necessarily <= targetDstSize)
|
||||
* or 0 if compression fails.
|
||||
* `srcSizePtr` : on success, *srcSizePtr will be updated to indicate how much bytes were read from `src`.
|
||||
* Note that this function may not consume the entire input.
|
||||
*/
|
||||
LZ4LIB_API int LZ4_compress_HC_continue_destSize(LZ4_streamHC_t* LZ4_streamHCPtr,
|
||||
const char* src, char* dst,
|
||||
int* srcSizePtr, int targetDstSize);
|
||||
|
||||
LZ4LIB_API int LZ4_saveDictHC (LZ4_streamHC_t* streamHCPtr, char* safeBuffer, int maxDictSize);
|
||||
|
||||
|
||||
|
||||
/*^**********************************************
|
||||
* !!!!!! STATIC LINKING ONLY !!!!!!
|
||||
***********************************************/
|
||||
|
||||
/*-******************************************************************
|
||||
* PRIVATE DEFINITIONS :
|
||||
* Do not use these definitions directly.
|
||||
* They are merely exposed to allow static allocation of `LZ4_streamHC_t`.
|
||||
* Declare an `LZ4_streamHC_t` directly, rather than any type below.
|
||||
* Even then, only do so in the context of static linking, as definitions may change between versions.
|
||||
********************************************************************/
|
||||
|
||||
#define LZ4HC_DICTIONARY_LOGSIZE 16
|
||||
#define LZ4HC_MAXD (1<<LZ4HC_DICTIONARY_LOGSIZE)
|
||||
#define LZ4HC_MAXD_MASK (LZ4HC_MAXD - 1)
|
||||
|
||||
#define LZ4HC_HASH_LOG 15
|
||||
#define LZ4HC_HASHTABLESIZE (1 << LZ4HC_HASH_LOG)
|
||||
#define LZ4HC_HASH_MASK (LZ4HC_HASHTABLESIZE - 1)
|
||||
|
||||
|
||||
/* Never ever use these definitions directly !
|
||||
* Declare or allocate an LZ4_streamHC_t instead.
|
||||
**/
|
||||
typedef struct LZ4HC_CCtx_internal LZ4HC_CCtx_internal;
|
||||
struct LZ4HC_CCtx_internal
|
||||
{
|
||||
LZ4_u32 hashTable[LZ4HC_HASHTABLESIZE];
|
||||
LZ4_u16 chainTable[LZ4HC_MAXD];
|
||||
const LZ4_byte* end; /* next block here to continue on current prefix */
|
||||
const LZ4_byte* prefixStart; /* Indexes relative to this position */
|
||||
const LZ4_byte* dictStart; /* alternate reference for extDict */
|
||||
LZ4_u32 dictLimit; /* below that point, need extDict */
|
||||
LZ4_u32 lowLimit; /* below that point, no more dict */
|
||||
LZ4_u32 nextToUpdate; /* index from which to continue dictionary update */
|
||||
short compressionLevel;
|
||||
LZ4_i8 favorDecSpeed; /* favor decompression speed if this flag set,
|
||||
otherwise, favor compression ratio */
|
||||
LZ4_i8 dirty; /* stream has to be fully reset if this flag is set */
|
||||
const LZ4HC_CCtx_internal* dictCtx;
|
||||
};
|
||||
|
||||
#define LZ4_STREAMHC_MINSIZE 262200 /* static size, for inter-version compatibility */
|
||||
union LZ4_streamHC_u {
|
||||
char minStateSize[LZ4_STREAMHC_MINSIZE];
|
||||
LZ4HC_CCtx_internal internal_donotuse;
|
||||
}; /* previously typedef'd to LZ4_streamHC_t */
|
||||
|
||||
/* LZ4_streamHC_t :
|
||||
* This structure allows static allocation of LZ4 HC streaming state.
|
||||
* This can be used to allocate statically on stack, or as part of a larger structure.
|
||||
*
|
||||
* Such state **must** be initialized using LZ4_initStreamHC() before first use.
|
||||
*
|
||||
* Note that invoking LZ4_initStreamHC() is not required when
|
||||
* the state was created using LZ4_createStreamHC() (which is recommended).
|
||||
* Using the normal builder, a newly created state is automatically initialized.
|
||||
*
|
||||
* Static allocation shall only be used in combination with static linking.
|
||||
*/
|
||||
|
||||
/* LZ4_initStreamHC() : v1.9.0+
|
||||
* Required before first use of a statically allocated LZ4_streamHC_t.
|
||||
* Before v1.9.0 : use LZ4_resetStreamHC() instead
|
||||
*/
|
||||
LZ4LIB_API LZ4_streamHC_t* LZ4_initStreamHC(void* buffer, size_t size);
|
||||
|
||||
|
||||
/*-************************************
|
||||
* Deprecated Functions
|
||||
**************************************/
|
||||
/* see lz4.h LZ4_DISABLE_DEPRECATE_WARNINGS to turn off deprecation warnings */
|
||||
|
||||
/* deprecated compression functions */
|
||||
LZ4_DEPRECATED("use LZ4_compress_HC() instead") LZ4LIB_API int LZ4_compressHC (const char* source, char* dest, int inputSize);
|
||||
LZ4_DEPRECATED("use LZ4_compress_HC() instead") LZ4LIB_API int LZ4_compressHC_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize);
|
||||
LZ4_DEPRECATED("use LZ4_compress_HC() instead") LZ4LIB_API int LZ4_compressHC2 (const char* source, char* dest, int inputSize, int compressionLevel);
|
||||
LZ4_DEPRECATED("use LZ4_compress_HC() instead") LZ4LIB_API int LZ4_compressHC2_limitedOutput(const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel);
|
||||
LZ4_DEPRECATED("use LZ4_compress_HC_extStateHC() instead") LZ4LIB_API int LZ4_compressHC_withStateHC (void* state, const char* source, char* dest, int inputSize);
|
||||
LZ4_DEPRECATED("use LZ4_compress_HC_extStateHC() instead") LZ4LIB_API int LZ4_compressHC_limitedOutput_withStateHC (void* state, const char* source, char* dest, int inputSize, int maxOutputSize);
|
||||
LZ4_DEPRECATED("use LZ4_compress_HC_extStateHC() instead") LZ4LIB_API int LZ4_compressHC2_withStateHC (void* state, const char* source, char* dest, int inputSize, int compressionLevel);
|
||||
LZ4_DEPRECATED("use LZ4_compress_HC_extStateHC() instead") LZ4LIB_API int LZ4_compressHC2_limitedOutput_withStateHC(void* state, const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel);
|
||||
LZ4_DEPRECATED("use LZ4_compress_HC_continue() instead") LZ4LIB_API int LZ4_compressHC_continue (LZ4_streamHC_t* LZ4_streamHCPtr, const char* source, char* dest, int inputSize);
|
||||
LZ4_DEPRECATED("use LZ4_compress_HC_continue() instead") LZ4LIB_API int LZ4_compressHC_limitedOutput_continue (LZ4_streamHC_t* LZ4_streamHCPtr, const char* source, char* dest, int inputSize, int maxOutputSize);
|
||||
|
||||
/* Obsolete streaming functions; degraded functionality; do not use!
|
||||
*
|
||||
* In order to perform streaming compression, these functions depended on data
|
||||
* that is no longer tracked in the state. They have been preserved as well as
|
||||
* possible: using them will still produce a correct output. However, use of
|
||||
* LZ4_slideInputBufferHC() will truncate the history of the stream, rather
|
||||
* than preserve a window-sized chunk of history.
|
||||
*/
|
||||
#if !defined(LZ4_STATIC_LINKING_ONLY_DISABLE_MEMORY_ALLOCATION)
|
||||
LZ4_DEPRECATED("use LZ4_createStreamHC() instead") LZ4LIB_API void* LZ4_createHC (const char* inputBuffer);
|
||||
LZ4_DEPRECATED("use LZ4_freeStreamHC() instead") LZ4LIB_API int LZ4_freeHC (void* LZ4HC_Data);
|
||||
#endif
|
||||
LZ4_DEPRECATED("use LZ4_saveDictHC() instead") LZ4LIB_API char* LZ4_slideInputBufferHC (void* LZ4HC_Data);
|
||||
LZ4_DEPRECATED("use LZ4_compress_HC_continue() instead") LZ4LIB_API int LZ4_compressHC2_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int compressionLevel);
|
||||
LZ4_DEPRECATED("use LZ4_compress_HC_continue() instead") LZ4LIB_API int LZ4_compressHC2_limitedOutput_continue (void* LZ4HC_Data, const char* source, char* dest, int inputSize, int maxOutputSize, int compressionLevel);
|
||||
LZ4_DEPRECATED("use LZ4_createStreamHC() instead") LZ4LIB_API int LZ4_sizeofStreamStateHC(void);
|
||||
LZ4_DEPRECATED("use LZ4_initStreamHC() instead") LZ4LIB_API int LZ4_resetStreamStateHC(void* state, char* inputBuffer);
|
||||
|
||||
|
||||
/* LZ4_resetStreamHC() is now replaced by LZ4_initStreamHC().
|
||||
* The intention is to emphasize the difference with LZ4_resetStreamHC_fast(),
|
||||
* which is now the recommended function to start a new stream of blocks,
|
||||
* but cannot be used to initialize a memory segment containing arbitrary garbage data.
|
||||
*
|
||||
* It is recommended to switch to LZ4_initStreamHC().
|
||||
* LZ4_resetStreamHC() will generate deprecation warnings in a future version.
|
||||
*/
|
||||
LZ4LIB_API void LZ4_resetStreamHC (LZ4_streamHC_t* streamHCPtr, int compressionLevel);
|
||||
|
||||
|
||||
#if defined (__cplusplus)
|
||||
}
|
||||
#endif
|
||||
|
||||
#endif /* LZ4_HC_H_19834876238432 */
|
||||
|
||||
|
||||
/*-**************************************************
|
||||
* !!!!! STATIC LINKING ONLY !!!!!
|
||||
* Following definitions are considered experimental.
|
||||
* They should not be linked from DLL,
|
||||
* as there is no guarantee of API stability yet.
|
||||
* Prototypes will be promoted to "stable" status
|
||||
* after successful usage in real-life scenarios.
|
||||
***************************************************/
|
||||
#ifdef LZ4_HC_STATIC_LINKING_ONLY /* protection macro */
|
||||
#ifndef LZ4_HC_SLO_098092834
|
||||
#define LZ4_HC_SLO_098092834
|
||||
|
||||
#define LZ4_STATIC_LINKING_ONLY /* LZ4LIB_STATIC_API */
|
||||
#include "lz4.h"
|
||||
|
||||
#if defined (__cplusplus)
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
/*! LZ4_setCompressionLevel() : v1.8.0+ (experimental)
|
||||
* It's possible to change compression level
|
||||
* between successive invocations of LZ4_compress_HC_continue*()
|
||||
* for dynamic adaptation.
|
||||
*/
|
||||
LZ4LIB_STATIC_API void LZ4_setCompressionLevel(
|
||||
LZ4_streamHC_t* LZ4_streamHCPtr, int compressionLevel);
|
||||
|
||||
/*! LZ4_favorDecompressionSpeed() : v1.8.2+ (experimental)
|
||||
* Opt. Parser will favor decompression speed over compression ratio.
|
||||
* Only applicable to levels >= LZ4HC_CLEVEL_OPT_MIN.
|
||||
*/
|
||||
LZ4LIB_STATIC_API void LZ4_favorDecompressionSpeed(
|
||||
LZ4_streamHC_t* LZ4_streamHCPtr, int favor);
|
||||
|
||||
/*! LZ4_resetStreamHC_fast() : v1.9.0+
|
||||
* When an LZ4_streamHC_t is known to be in a internally coherent state,
|
||||
* it can often be prepared for a new compression with almost no work, only
|
||||
* sometimes falling back to the full, expensive reset that is always required
|
||||
* when the stream is in an indeterminate state (i.e., the reset performed by
|
||||
* LZ4_resetStreamHC()).
|
||||
*
|
||||
* LZ4_streamHCs are guaranteed to be in a valid state when:
|
||||
* - returned from LZ4_createStreamHC()
|
||||
* - reset by LZ4_resetStreamHC()
|
||||
* - memset(stream, 0, sizeof(LZ4_streamHC_t))
|
||||
* - the stream was in a valid state and was reset by LZ4_resetStreamHC_fast()
|
||||
* - the stream was in a valid state and was then used in any compression call
|
||||
* that returned success
|
||||
* - the stream was in an indeterminate state and was used in a compression
|
||||
* call that fully reset the state (LZ4_compress_HC_extStateHC()) and that
|
||||
* returned success
|
||||
*
|
||||
* Note:
|
||||
* A stream that was last used in a compression call that returned an error
|
||||
* may be passed to this function. However, it will be fully reset, which will
|
||||
* clear any existing history and settings from the context.
|
||||
*/
|
||||
LZ4LIB_STATIC_API void LZ4_resetStreamHC_fast(
|
||||
LZ4_streamHC_t* LZ4_streamHCPtr, int compressionLevel);
|
||||
|
||||
/*! LZ4_compress_HC_extStateHC_fastReset() :
|
||||
* A variant of LZ4_compress_HC_extStateHC().
|
||||
*
|
||||
* Using this variant avoids an expensive initialization step. It is only safe
|
||||
* to call if the state buffer is known to be correctly initialized already
|
||||
* (see above comment on LZ4_resetStreamHC_fast() for a definition of
|
||||
* "correctly initialized"). From a high level, the difference is that this
|
||||
* function initializes the provided state with a call to
|
||||
* LZ4_resetStreamHC_fast() while LZ4_compress_HC_extStateHC() starts with a
|
||||
* call to LZ4_resetStreamHC().
|
||||
*/
|
||||
LZ4LIB_STATIC_API int LZ4_compress_HC_extStateHC_fastReset (
|
||||
void* state,
|
||||
const char* src, char* dst,
|
||||
int srcSize, int dstCapacity,
|
||||
int compressionLevel);
|
||||
|
||||
/*! LZ4_attach_HC_dictionary() :
|
||||
* This is an experimental API that allows for the efficient use of a
|
||||
* static dictionary many times.
|
||||
*
|
||||
* Rather than re-loading the dictionary buffer into a working context before
|
||||
* each compression, or copying a pre-loaded dictionary's LZ4_streamHC_t into a
|
||||
* working LZ4_streamHC_t, this function introduces a no-copy setup mechanism,
|
||||
* in which the working stream references the dictionary stream in-place.
|
||||
*
|
||||
* Several assumptions are made about the state of the dictionary stream.
|
||||
* Currently, only streams which have been prepared by LZ4_loadDictHC() should
|
||||
* be expected to work.
|
||||
*
|
||||
* Alternatively, the provided dictionary stream pointer may be NULL, in which
|
||||
* case any existing dictionary stream is unset.
|
||||
*
|
||||
* A dictionary should only be attached to a stream without any history (i.e.,
|
||||
* a stream that has just been reset).
|
||||
*
|
||||
* The dictionary will remain attached to the working stream only for the
|
||||
* current stream session. Calls to LZ4_resetStreamHC(_fast) will remove the
|
||||
* dictionary context association from the working stream. The dictionary
|
||||
* stream (and source buffer) must remain in-place / accessible / unchanged
|
||||
* through the lifetime of the stream session.
|
||||
*/
|
||||
LZ4LIB_STATIC_API void LZ4_attach_HC_dictionary(
|
||||
LZ4_streamHC_t *working_stream,
|
||||
const LZ4_streamHC_t *dictionary_stream);
|
||||
|
||||
#if defined (__cplusplus)
|
||||
}
|
||||
#endif
|
||||
|
||||
#endif /* LZ4_HC_SLO_098092834 */
|
||||
#endif /* LZ4_HC_STATIC_LINKING_ONLY */
|
||||
Reference in New Issue
Block a user