thirdparty-miniz/miniz_tinfl.h

#pragma once
#include "miniz_common.h"
// ------------------- Low-level Decompression API Definitions

// Decompression flags used by tinfl_decompress().
// TINFL_FLAG_PARSE_ZLIB_HEADER: If set, the input has a valid zlib header and ends with an adler32 checksum (it's a valid zlib stream). Otherwise, the input is a raw deflate stream.
// TINFL_FLAG_HAS_MORE_INPUT: If set, there are more input bytes available beyond the end of the supplied input buffer. If clear, the input buffer contains all remaining input.
// TINFL_FLAG_USING_NON_WRAPPING_OUTPUT_BUF: If set, the output buffer is large enough to hold the entire decompressed stream. If clear, the output buffer is at least the size of the dictionary (typically 32KB).
// TINFL_FLAG_COMPUTE_ADLER32: Force adler-32 checksum computation of the decompressed bytes.
enum
{
  TINFL_FLAG_PARSE_ZLIB_HEADER = 1,
  TINFL_FLAG_HAS_MORE_INPUT = 2,
  TINFL_FLAG_USING_NON_WRAPPING_OUTPUT_BUF = 4,
  TINFL_FLAG_COMPUTE_ADLER32 = 8
};

// High level decompression functions:
// tinfl_decompress_mem_to_heap() decompresses a block in memory to a heap block allocated via malloc().
// On entry:
//  pSrc_buf, src_buf_len: Pointer and size of the Deflate or zlib source data to decompress.
// On return:
//  Function returns a pointer to the decompressed data, or NULL on failure.
//  *pOut_len will be set to the decompressed data's size, which could be larger than src_buf_len on uncompressible data.
//  The caller must call mz_free() on the returned block when it's no longer needed.
void *tinfl_decompress_mem_to_heap(const void *pSrc_buf, size_t src_buf_len, size_t *pOut_len, int flags);

// tinfl_decompress_mem_to_mem() decompresses a block in memory to another block in memory.
// Returns TINFL_DECOMPRESS_MEM_TO_MEM_FAILED on failure, or the number of bytes written on success.
#define TINFL_DECOMPRESS_MEM_TO_MEM_FAILED ((size_t)(-1))
size_t tinfl_decompress_mem_to_mem(void *pOut_buf, size_t out_buf_len, const void *pSrc_buf, size_t src_buf_len, int flags);

// tinfl_decompress_mem_to_callback() decompresses a block in memory to an internal 32KB buffer, and a user provided callback function will be called to flush the buffer.
// Returns 1 on success or 0 on failure.
typedef int (*tinfl_put_buf_func_ptr)(const void* pBuf, int len, void *pUser);
int tinfl_decompress_mem_to_callback(const void *pIn_buf, size_t *pIn_buf_size, tinfl_put_buf_func_ptr pPut_buf_func, void *pPut_buf_user, int flags);

struct tinfl_decompressor_tag; typedef struct tinfl_decompressor_tag tinfl_decompressor;

// Max size of LZ dictionary.
#define TINFL_LZ_DICT_SIZE 32768

// Return status.
typedef enum
{
  TINFL_STATUS_BAD_PARAM = -3,
  TINFL_STATUS_ADLER32_MISMATCH = -2,
  TINFL_STATUS_FAILED = -1,
  TINFL_STATUS_DONE = 0,
  TINFL_STATUS_NEEDS_MORE_INPUT = 1,
  TINFL_STATUS_HAS_MORE_OUTPUT = 2
} tinfl_status;

// Initializes the decompressor to its initial state.
#define tinfl_init(r) do { (r)->m_state = 0; } MZ_MACRO_END
#define tinfl_get_adler32(r) (r)->m_check_adler32

// Main low-level decompressor coroutine function. This is the only function actually needed for decompression. All the other functions are just high-level helpers for improved usability.
// This is a universal API, i.e. it can be used as a building block to build any desired higher level decompression API. In the limit case, it can be called once per every byte input or output.
tinfl_status tinfl_decompress(tinfl_decompressor *r, const mz_uint8 *pIn_buf_next, size_t *pIn_buf_size, mz_uint8 *pOut_buf_start, mz_uint8 *pOut_buf_next, size_t *pOut_buf_size, const mz_uint32 decomp_flags);

// Internal/private bits follow.
enum
{
  TINFL_MAX_HUFF_TABLES = 3, TINFL_MAX_HUFF_SYMBOLS_0 = 288, TINFL_MAX_HUFF_SYMBOLS_1 = 32, TINFL_MAX_HUFF_SYMBOLS_2 = 19,
  TINFL_FAST_LOOKUP_BITS = 10, TINFL_FAST_LOOKUP_SIZE = 1 << TINFL_FAST_LOOKUP_BITS
};

typedef struct
{
  mz_uint8 m_code_size[TINFL_MAX_HUFF_SYMBOLS_0];
  mz_int16 m_look_up[TINFL_FAST_LOOKUP_SIZE], m_tree[TINFL_MAX_HUFF_SYMBOLS_0 * 2];
} tinfl_huff_table;

#if MINIZ_HAS_64BIT_REGISTERS
  #define TINFL_USE_64BIT_BITBUF 1
#endif

#if TINFL_USE_64BIT_BITBUF
  typedef mz_uint64 tinfl_bit_buf_t;
  #define TINFL_BITBUF_SIZE (64)
#else
  typedef mz_uint32 tinfl_bit_buf_t;
  #define TINFL_BITBUF_SIZE (32)
#endif

struct tinfl_decompressor_tag
{
  mz_uint32 m_state, m_num_bits, m_zhdr0, m_zhdr1, m_z_adler32, m_final, m_type, m_check_adler32, m_dist, m_counter, m_num_extra, m_table_sizes[TINFL_MAX_HUFF_TABLES];
  tinfl_bit_buf_t m_bit_buf;
  size_t m_dist_from_out_buf_start;
  tinfl_huff_table m_tables[TINFL_MAX_HUFF_TABLES];
  mz_uint8 m_raw_header[4], m_len_codes[TINFL_MAX_HUFF_SYMBOLS_0 + TINFL_MAX_HUFF_SYMBOLS_1 + 137];
};