328 lines
12 KiB
C
328 lines
12 KiB
C
|
/* -*- mode: c; tab-width: 4; indent-tabs-mode: nil; -*- */
|
||
|
|
|
||
|
|
/*
|
||
|
|
* This file is part of liblzg.
|
||
|
|
*
|
||
|
|
* Copyright (c) 2010-2018 Marcus Geelnard
|
||
|
|
*
|
||
|
|
* This software is provided 'as-is', without any express or implied
|
||
|
|
* warranty. In no event will the authors be held liable for any damages
|
||
|
|
* arising from the use of this software.
|
||
|
|
*
|
||
|
|
* Permission is granted to anyone to use this software for any purpose,
|
||
|
|
* including commercial applications, and to alter it and redistribute it
|
||
|
|
* freely, subject to the following restrictions:
|
||
|
|
*
|
||
|
|
* 1. The origin of this software must not be misrepresented; you must not
|
||
|
|
* claim that you wrote the original software. If you use this software
|
||
|
|
* in a product, an acknowledgment in the product documentation would
|
||
|
|
* be appreciated but is not required.
|
||
|
|
*
|
||
|
|
* 2. Altered source versions must be plainly marked as such, and must not
|
||
|
|
* be misrepresented as being the original software.
|
||
|
|
*
|
||
|
|
* 3. This notice may not be removed or altered from any source
|
||
|
|
* distribution.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#ifndef _LIBLZG_H_
|
||
|
|
#define _LIBLZG_H_
|
||
|
|
|
||
|
|
#ifdef __cplusplus
|
||
|
|
extern "C" {
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#define LZG_VERSION "1.0.10" /**< @brief LZG library version string */
|
||
|
|
#define LZG_VERNUM 0x0100000a /**< @brief LZG library version number (strictly
|
||
|
|
incremental) */
|
||
|
|
#define LZG_VER_MAJOR 1 /**< @brief LZG library major version */
|
||
|
|
#define LZG_VER_MINOR 0 /**< @brief LZG library minor version */
|
||
|
|
#define LZG_VER_REVISION 10 /**< @brief LZG library revision */
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @file
|
||
|
|
* @mainpage
|
||
|
|
*
|
||
|
|
* @section intro_sec Introduction
|
||
|
|
*
|
||
|
|
* liblzg is a minimal implementation of an LZ77 class compression library. The
|
||
|
|
* main characteristic of the library is that the decoding routine is very
|
||
|
|
* simple, fast and requires no extra memory (except for the encoded and decoded
|
||
|
|
* data buffers).
|
||
|
|
*
|
||
|
|
* @section funcs_sec Functions
|
||
|
|
*
|
||
|
|
* @li LZG_MaxEncodedSize() - Determine the maximum size of the encoded data for
|
||
|
|
* a given uncompressed buffer (worst case).
|
||
|
|
* @li LZG_InitEncoderConfig() - Set default encoder configuration.
|
||
|
|
* @li LZG_Encode() - Encode uncompressed data as LZG coded data.
|
||
|
|
* @li LZG_EncodeFull() - Same as LZG_Encode(), but using custom memory
|
||
|
|
* allocation.
|
||
|
|
* @li LZG_WorkMemSize() - Determine the amount of memory required for encoding
|
||
|
|
* (useful for LZG_EncodeFull()).
|
||
|
|
*
|
||
|
|
* @li LZG_DecodedSize() - Determine the size of the decoded data for a given
|
||
|
|
* LZG coded buffer.
|
||
|
|
* @li LZG_Decode() - Decode LZG coded data.
|
||
|
|
*
|
||
|
|
* @li LZG_Version() - Get the version of the LZG library.
|
||
|
|
* @li LZG_VersionString() - Get the version of the LZG library.
|
||
|
|
*
|
||
|
|
* @section compr_sec Compression
|
||
|
|
* Here is a simple example of compressing an uncompressed data buffer (given
|
||
|
|
* as buf/bufSize).
|
||
|
|
*
|
||
|
|
* @code
|
||
|
|
* unsigned char *encBuf;
|
||
|
|
* lzg_uint32_t encSize, maxEncSize;
|
||
|
|
*
|
||
|
|
* // Determine maximum size of compressed data
|
||
|
|
* maxEncSize = LZG_MaxEncodedSize(bufSize);
|
||
|
|
*
|
||
|
|
* // Allocate memory for the compressed data
|
||
|
|
* encBuf = (unsigned char*) malloc(maxEncSize);
|
||
|
|
* if (encBuf)
|
||
|
|
* {
|
||
|
|
* // Compress
|
||
|
|
* encSize = LZG_Encode(buf, bufSize, encBuf, maxEncSize, NULL);
|
||
|
|
* if (encSize)
|
||
|
|
* {
|
||
|
|
* // Compressed data is now in encBuf, use it...
|
||
|
|
* // ...
|
||
|
|
* }
|
||
|
|
* else
|
||
|
|
* fprintf(stderr, "Compression failed!\n");
|
||
|
|
*
|
||
|
|
* // Free memory when we're done with the compressed data
|
||
|
|
* free(encBuf);
|
||
|
|
* }
|
||
|
|
* else
|
||
|
|
* fprintf(stderr, "Out of memory!\n");
|
||
|
|
* @endcode
|
||
|
|
*
|
||
|
|
* @section decompr_sec Decompression
|
||
|
|
* Here is a simple example of decompressing a compressed data buffer (given
|
||
|
|
* as buf/bufSize).
|
||
|
|
*
|
||
|
|
* @code
|
||
|
|
* unsigned char *decBuf;
|
||
|
|
* lzg_uint32_t decSize;
|
||
|
|
*
|
||
|
|
* // Determine size of decompressed data
|
||
|
|
* decSize = LZG_DecodedSize(buf, bufSize);
|
||
|
|
* if (decSize)
|
||
|
|
* {
|
||
|
|
* // Allocate memory for the decompressed data
|
||
|
|
* decBuf = (unsigned char*) malloc(decSize);
|
||
|
|
* if (decBuf)
|
||
|
|
* {
|
||
|
|
* // Decompress
|
||
|
|
* decSize = LZG_Decode(buf, bufSize, decBuf, decSize);
|
||
|
|
* if (decSize)
|
||
|
|
* {
|
||
|
|
* // Uncompressed data is now in decBuf, use it...
|
||
|
|
* // ...
|
||
|
|
* }
|
||
|
|
* else
|
||
|
|
* printf("Decompression failed (bad data)!\n");
|
||
|
|
*
|
||
|
|
* // Free memory when we're done with the decompressed data
|
||
|
|
* free(decBuf);
|
||
|
|
* }
|
||
|
|
* else
|
||
|
|
* printf("Out of memory!\n");
|
||
|
|
* }
|
||
|
|
* else
|
||
|
|
* printf("Bad input data!\n");
|
||
|
|
* @endcode
|
||
|
|
*/
|
||
|
|
|
||
|
|
/* Basic types */
|
||
|
|
typedef int lzg_bool_t; /**< @brief Boolean (@ref LZG_TRUE/@ref LZG_FALSE) */
|
||
|
|
typedef int lzg_int32_t; /**< @brief Signed 32-bit integer */
|
||
|
|
typedef unsigned int lzg_uint32_t; /**< @brief Unsigned 32-bit integer */
|
||
|
|
|
||
|
|
#define LZG_FALSE 0 /**< @brief Boolean FALSE (see @ref lzg_bool_t) */
|
||
|
|
#define LZG_TRUE 1 /**< @brief Boolean TRUE (see @ref lzg_bool_t) */
|
||
|
|
|
||
|
|
/* Compression levels */
|
||
|
|
#define LZG_LEVEL_1 1 /**< @brief Lowest/fastest compression level */
|
||
|
|
#define LZG_LEVEL_2 2 /**< @brief Compression level 2 */
|
||
|
|
#define LZG_LEVEL_3 3 /**< @brief Compression level 3 */
|
||
|
|
#define LZG_LEVEL_4 4 /**< @brief Compression level 4 */
|
||
|
|
#define LZG_LEVEL_5 5 /**< @brief Medium compression level */
|
||
|
|
#define LZG_LEVEL_6 6 /**< @brief Compression level 6 */
|
||
|
|
#define LZG_LEVEL_7 7 /**< @brief Compression level 7 */
|
||
|
|
#define LZG_LEVEL_8 8 /**< @brief Compression level 8 */
|
||
|
|
#define LZG_LEVEL_9 9 /**< @brief Best/slowest compression level */
|
||
|
|
|
||
|
|
/** @brief Default compression level */
|
||
|
|
#define LZG_LEVEL_DEFAULT LZG_LEVEL_5
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Progress callback function.
|
||
|
|
* @param[in] progress The current progress (0-100).
|
||
|
|
* @param[in] userdata User supplied data pointer.
|
||
|
|
*/
|
||
|
|
typedef void (*LZGPROGRESSFUN)(lzg_int32_t progress, void *userdata);
|
||
|
|
|
||
|
|
/** @brief LZG compression configuration parameters.
|
||
|
|
*
|
||
|
|
* This structure is used for passing configuration options to the LZG_Encode()
|
||
|
|
* function. Initialize this structure to default values with
|
||
|
|
* @ref LZG_InitEncoderConfig().
|
||
|
|
*/
|
||
|
|
typedef struct {
|
||
|
|
/** @brief Compression level (1-9).
|
||
|
|
|
||
|
|
For convenience, you can use the predefined constants
|
||
|
|
@ref LZG_LEVEL_1 (fast) to @ref LZG_LEVEL_9 (slow), or
|
||
|
|
@ref LZG_LEVEL_DEFAULT.
|
||
|
|
|
||
|
|
Default value: LZG_LEVEL_DEFAULT */
|
||
|
|
lzg_int32_t level;
|
||
|
|
|
||
|
|
/** @brief Use fast method (LZG_FALSE or LZG_TRUE).
|
||
|
|
|
||
|
|
Boolean flag that specifies whether or not to use a faster encoding
|
||
|
|
acceleration data structure, which requires more memory. When using the
|
||
|
|
fast method, the compression ratio is usually slightly improved.
|
||
|
|
|
||
|
|
Default value: LZG_TRUE */
|
||
|
|
lzg_bool_t fast;
|
||
|
|
|
||
|
|
/** @brief Encoding progress callback function.
|
||
|
|
|
||
|
|
This function will be called during compression to report progress
|
||
|
|
back to the caller (set this to NULL to disable progress
|
||
|
|
callback).
|
||
|
|
|
||
|
|
Default value: NULL */
|
||
|
|
LZGPROGRESSFUN progressfun;
|
||
|
|
|
||
|
|
/** @brief User data pointer for the progress callback function.
|
||
|
|
|
||
|
|
A user defined data pointer that can point to anything that the
|
||
|
|
progress callback function may need, such as an object reference
|
||
|
|
(this can set to NULL if the callback function does not need it).
|
||
|
|
|
||
|
|
Default value: NULL */
|
||
|
|
void *userdata;
|
||
|
|
} lzg_encoder_config_t;
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Determine the maximum size of the encoded data for a given uncompressed
|
||
|
|
* buffer.
|
||
|
|
* @param[in] insize Size of the uncompressed buffer (number of bytes).
|
||
|
|
* @return Worst case (maximum) size of the encoded data.
|
||
|
|
*/
|
||
|
|
lzg_uint32_t LZG_MaxEncodedSize(lzg_uint32_t insize);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Initialize an encoder configuration object.
|
||
|
|
* @param[out] config Configuration object.
|
||
|
|
*/
|
||
|
|
void LZG_InitEncoderConfig(lzg_encoder_config_t *config);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Determine the amount of memory required for encoding.
|
||
|
|
* @param[in] config Compression configuration (if set to NULL, default encoder
|
||
|
|
* configuration parameters are used).
|
||
|
|
* @retrun The size of the buffer required.
|
||
|
|
*/
|
||
|
|
lzg_uint32_t LZG_WorkMemSize(lzg_encoder_config_t *config);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Encode uncompressed data using the LZG coder (i.e. compress the data).
|
||
|
|
* @param[in] in Input (uncompressed) buffer.
|
||
|
|
* @param[in] insize Size of the input buffer (number of bytes).
|
||
|
|
* @param[out] out Output (compressed) buffer.
|
||
|
|
* @param[in] outsize Size of the output buffer (number of bytes).
|
||
|
|
* @param[in] config Compression configuration (if set to NULL, default encoder
|
||
|
|
* configuration parameters are used).
|
||
|
|
* @return The size of the encoded data, or zero if the function failed
|
||
|
|
* (e.g. if the end of the output buffer was reached before the
|
||
|
|
* entire input buffer was encoded).
|
||
|
|
* @note For the slow method (config->fast = 0), the memory requirement during
|
||
|
|
* compression is 136 KB (LZG_LEVEL_1) to 2 MB (LZG_LEVEL_9). For the fast
|
||
|
|
* method (config->fast = 1), the memory requirement is 64 MB (LZG_LEVEL_1) to
|
||
|
|
* 66 MB (LZG_LEVEL_9). Also note that these figures are doubled on 64-bit
|
||
|
|
* systems.
|
||
|
|
*/
|
||
|
|
lzg_uint32_t LZG_Encode(const unsigned char *in, lzg_uint32_t insize,
|
||
|
|
unsigned char *out, lzg_uint32_t outsize,
|
||
|
|
lzg_encoder_config_t *config);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Encode uncompressed data using the LZG coder (i.e. compress the data).
|
||
|
|
* @param[in] in Input (uncompressed) buffer.
|
||
|
|
* @param[in] insize Size of the input buffer (number of bytes).
|
||
|
|
* @param[out] out Output (compressed) buffer.
|
||
|
|
* @param[in] outsize Size of the output buffer (number of bytes).
|
||
|
|
* @param[in] config Compression configuration (if set to NULL, default encoder
|
||
|
|
* configuration parameters are used).
|
||
|
|
* @param[in] workmem Buffer to be used for compression, or NULL. See
|
||
|
|
* @ref LZG_WorkMemSize.
|
||
|
|
* @return The size of the encoded data, or zero if the function failed
|
||
|
|
* (e.g. if the end of the output buffer was reached before the
|
||
|
|
* entire input buffer was encoded).
|
||
|
|
* @note For the slow method (config->fast = 0), the memory requirement during
|
||
|
|
* compression is 136 KB (LZG_LEVEL_1) to 2 MB (LZG_LEVEL_9). For the fast
|
||
|
|
* method (config->fast = 1), the memory requirement is 64 MB (LZG_LEVEL_1) to
|
||
|
|
* 66 MB (LZG_LEVEL_9). Also note that these figures are doubled on 64-bit
|
||
|
|
* systems.
|
||
|
|
*/
|
||
|
|
lzg_uint32_t LZG_EncodeFull(const unsigned char *in, lzg_uint32_t insize,
|
||
|
|
unsigned char *out, lzg_uint32_t outsize,
|
||
|
|
lzg_encoder_config_t *config,
|
||
|
|
void *workmem);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Determine the size of the decoded data for a given LZG coded buffer.
|
||
|
|
* @param[in] in Input (compressed) buffer.
|
||
|
|
* @param[in] insize Size of the input buffer (number of bytes). This does
|
||
|
|
* not have to be the size of the entire compressed data, but
|
||
|
|
* it has to be at least 7 bytes (the first few bytes of the
|
||
|
|
* header, including the decompression size).
|
||
|
|
* @return The size of the decoded data, or zero if the function failed
|
||
|
|
* (e.g. if the magic header ID could not be found).
|
||
|
|
*/
|
||
|
|
lzg_uint32_t LZG_DecodedSize(const unsigned char *in, lzg_uint32_t insize);
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Decode LZG coded data.
|
||
|
|
* @param[in] in Input (compressed) buffer.
|
||
|
|
* @param[in] insize Size of the input buffer (number of bytes).
|
||
|
|
* @param[out] out Output (uncompressed) buffer.
|
||
|
|
* @param[in] outsize Size of the output buffer (number of bytes).
|
||
|
|
* @return The size of the decoded data, or zero if the function failed
|
||
|
|
* (e.g. if the end of the output buffer was reached before the
|
||
|
|
* entire input buffer was decoded).
|
||
|
|
*/
|
||
|
|
lzg_uint32_t LZG_Decode(const unsigned char *in, lzg_uint32_t insize,
|
||
|
|
unsigned char *out, lzg_uint32_t outsize);
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Get the version of the LZG library.
|
||
|
|
* @return The version of the LZG library, on the same format as
|
||
|
|
* @ref LZG_VERNUM.
|
||
|
|
*/
|
||
|
|
lzg_uint32_t LZG_Version(void);
|
||
|
|
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Get the version string of the LZG library.
|
||
|
|
* @return The version of the LZG library, on the same format as
|
||
|
|
* @ref LZG_VERSION.
|
||
|
|
*/
|
||
|
|
const char* LZG_VersionString(void);
|
||
|
|
|
||
|
|
#ifdef __cplusplus
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#endif // _LIBLZG_H_
|