ardupilot/libraries/AP_ROMFS/tinf.h

/*
 * uzlib  -  tiny deflate/inflate library (deflate, gzip, zlib)
 *
 * Copyright (c) 2003 by Joergen Ibsen / Jibz
 * All Rights Reserved
 * http://www.ibsensoftware.com/
 *
 * Copyright (c) 2014-2016 by Paul Sokolovsky
 */

#ifndef TINF_H_INCLUDED
#define TINF_H_INCLUDED

#include <stdlib.h>
#include <stdint.h>
#include <stdbool.h>

/* calling convention */
#ifndef TINFCC
 #ifdef __WATCOMC__
  #define TINFCC __cdecl
 #else
  #define TINFCC
 #endif
#endif

#ifdef __cplusplus
extern "C" {
#endif

/* ok status, more data produced */
#define TINF_OK             0
/* end of compressed stream reached */
#define TINF_DONE           1
#define TINF_DATA_ERROR    (-3)
#define TINF_CHKSUM_ERROR  (-4)
#define TINF_DICT_ERROR    (-5)

/* checksum types */
#define TINF_CHKSUM_NONE  0
#define TINF_CHKSUM_ADLER 1
#define TINF_CHKSUM_CRC   2

/* helper macros */
#define TINF_ARRAY_SIZE(arr) (sizeof(arr) / sizeof(*(arr)))

/* data structures */

typedef struct {
   unsigned short table[16];  /* table of code length counts */
   unsigned short trans[288]; /* code -> symbol translation table */
} TINF_TREE;

struct TINF_DATA;
typedef struct TINF_DATA {
   /* Pointer to the next byte in the input buffer */
   const unsigned char *source;
   /* Pointer to the next byte past the input buffer (source_limit = source + len) */
   const unsigned char *source_limit;
   /* If source_limit == NULL, or source >= source_limit, this function
      will be used to read next byte from source stream. The function may
      also return -1 in
      case of EOF (or irrecoverable error). Note that besides returning
      the next byte, it may also update source and sourceRemaining fields,
      thus allowing for buffered operation. */
   int (*readSource)(struct TINF_DATA *data);

   unsigned int tag;
   unsigned int bitcount;

    /* Buffer start */
    unsigned char *destStart;
    /* Buffer total size */
    unsigned int destSize;
    /* Current pointer in buffer */
    unsigned char *dest;
    /* Remaining bytes in buffer */
    unsigned int destRemaining;

    /* Accumulating checksum */
    unsigned int checksum;
    char checksum_type;
    bool eof;

    int btype;
    int bfinal;
    unsigned int curlen;
    int lzOff;
    unsigned char *dict_ring;
    unsigned int dict_size;
    unsigned int dict_idx;

   TINF_TREE ltree; /* dynamic length/symbol tree */
   TINF_TREE dtree; /* dynamic distance tree */
} TINF_DATA;

#define TINF_PUT(d, c) \
    { \
        *d->dest++ = c; \
        if (d->dict_ring) { d->dict_ring[d->dict_idx++] = c; if (d->dict_idx == d->dict_size) d->dict_idx = 0; } \
    }

unsigned char TINFCC uzlib_get_byte(TINF_DATA *d);

/* Decompression API */

void TINFCC uzlib_init(void);
void TINFCC uzlib_uncompress_init(TINF_DATA *d, void *dict, unsigned int dictLen);
int  TINFCC uzlib_uncompress(TINF_DATA *d);
int  TINFCC uzlib_uncompress_chksum(TINF_DATA *d);

int TINFCC uzlib_zlib_parse_header(TINF_DATA *d);
int TINFCC uzlib_gzip_parse_header(TINF_DATA *d);

/* Compression API */

void TINFCC uzlib_compress(void *data, const uint8_t *src, unsigned slen);

/* Checksum API */

/* prev_sum is previous value for incremental computation, 1 initially */
uint32_t TINFCC uzlib_adler32(const void *data, unsigned int length, uint32_t prev_sum);
/* crc is previous value for incremental computation, 0xffffffff initially */
uint32_t TINFCC uzlib_crc32(const void *data, unsigned int length, uint32_t crc);

#ifdef __cplusplus
} /* extern "C" */
#endif

#endif /* TINF_H_INCLUDED */