v4k-git-backup/engine/split/v4k_pack.h

// ----------------------------------------------------------------------------
// endianness

API int is_big();
API int is_little();

API uint16_t swap16( uint16_t x );
API uint32_t swap32( uint32_t x );
API uint64_t swap64( uint64_t x );
API float    swap32f(float n);
API double   swap64f(double n);

API uint16_t    lil16(uint16_t n); // swap16 as lil
API uint32_t    lil32(uint32_t n); // swap32 as lil
API uint64_t    lil64(uint64_t n); // swap64 as lil
API float       lil32f(float n);   // swap32 as lil
API double      lil64f(double n);  // swap64 as lil

API uint16_t    big16(uint16_t n); // swap16 as big
API uint32_t    big32(uint32_t n); // swap32 as big
API uint64_t    big64(uint64_t n); // swap64 as big
API float       big32f(float n);   // swap32 as big
API double      big64f(double n);  // swap64 as big

API uint16_t* lil16p(void *p, int sz);
API uint32_t* lil32p(void *p, int sz);
API uint64_t* lil64p(void *p, int sz);
API float   * lil32pf(void *p, int sz);
API double  * lil64pf(void *p, int sz);

API uint16_t*   big16p(void *p, int sz);
API uint32_t*   big32p(void *p, int sz);
API uint64_t*   big64p(void *p, int sz);
API float   *   big32pf(void *p, int sz);
API double  * big64pf(void *p, int sz);

#if is(cl)
#define swap16 _byteswap_ushort
#define swap32 _byteswap_ulong
#define swap64 _byteswap_uint64
#elif is(gcc)
#define swap16 __builtin_bswap16
#define swap32 __builtin_bswap32
#define swap64 __builtin_bswap64
#endif

#define hton16 big16
#define ntoh16 big16
#define hton32 big32
#define ntoh32 big32
#define hton64 big64
#define ntoh64 big64

#define IS_BIG    ((*(uint16_t *)"\0\1") == 1)
#define IS_LITTLE ((*(uint16_t *)"\0\1") != 1)

// ----------------------------------------------------------------------------
// half packing

typedef uint16_t half;
API float half_to_float(half value);
API half  float_to_half(float value);

// ----------------------------------------------------------------------------
// int packing

// pack16i() -- store a 16-bit int into a char buffer (like htons())
// pack32i() -- store a 32-bit int into a char buffer (like htonl())
// pack64i() -- store a 64-bit int into a char buffer (like htonl())

API void pack16i(uint8_t *buf, uint16_t i, int swap);
API void pack32i(uint8_t *buf, uint32_t i, int swap);
API void pack64i(uint8_t *buf, uint64_t i, int swap);

// unpack16i() -- unpack a 16-bit int from a char buffer (like ntohs())
// unpack32i() -- unpack a 32-bit int from a char buffer (like ntohl())
// unpack64i() -- unpack a 64-bit int from a char buffer (like ntohl())
// changes unsigned numbers to signed if needed.

API int16_t unpack16i(const uint8_t *buf, int swap);
API int32_t unpack32i(const uint8_t *buf, int swap);
API int64_t unpack64i(const uint8_t *buf, int swap);

// ----------------------------------------------------------------------------
// float un/packing: 8 (micro), 16 (half), 32 (float), 64 (double) types

#define pack754_8(f)    (  pack754((f),  8,  4))
#define pack754_16(f)   (  pack754((f), 16,  5))
#define pack754_32(f)   (  pack754((f), 32,  8))
#define pack754_64(f)   (  pack754((f), 64, 11))
#define unpack754_8(u)  (unpack754((u),  8,  4))
#define unpack754_16(u) (unpack754((u), 16,  5))
#define unpack754_32(u) (unpack754((u), 32,  8))
#define unpack754_64(u) (unpack754((u), 64, 11))

API    uint64_t pack754(long double f, unsigned bits, unsigned expbits);
API long double unpack754(uint64_t i, unsigned bits, unsigned expbits);

// ----------------------------------------------------------------------------
// variable-length integer packing

API uint64_t pack64uv( uint8_t *buffer, uint64_t value );
API uint64_t unpack64uv( const uint8_t *buffer, uint64_t *value );
API uint64_t pack64iv( uint8_t *buffer, int64_t value_ );
API uint64_t unpack64iv( const uint8_t *buffer, int64_t *value );

// ----------------------------------------------------------------------------
// msgpack v5, schema based struct/buffer bitpacking

// api v2

API int  msgpack(const char *fmt, ... );                // va arg pack "n,b,u,d/i,s,p,f/g,e,[,{"
API bool msgunpack(const char *fmt, ... );              // va arg pack "n,b,u,d/i,s,p,f/g,e,[,{"

// api v1

API int msgpack_new(uint8_t *w, size_t l);
API int msgpack_nil();                                  // write null
API int msgpack_chr(bool n);                            // write boolean
API int msgpack_uns(uint64_t n);                        // write unsigned integer
API int msgpack_int(int64_t n);                         // write integer
API int msgpack_str(const char *s);                     // write string
API int msgpack_bin(const char *s, size_t n);           // write binary pointer
API int msgpack_flt(double g);                          // write real
API int msgpack_ext(uint8_t key, void *val, size_t n);  // write extension type
API int msgpack_arr(uint32_t n);                        // write array mark for next N items
API int msgpack_map(uint32_t n);                        // write map mark for next N pairs (N keys + N values)
API int msgpack_eof();                                  // write full?
API int msgpack_err();                                  // write error?

API bool msgunpack_new( const void *opaque_or_FILE, size_t bytes );
API bool msgunpack_nil();
API bool msgunpack_chr(bool *chr);
API bool msgunpack_uns(uint64_t *uns);
API bool msgunpack_int(int64_t *sig);
API bool msgunpack_str(char **str);
API bool msgunpack_bin(void **bin, uint64_t *len);
API bool msgunpack_flt(float *flt);
API bool msgunpack_dbl(double *dbl);
API bool msgunpack_ext(uint8_t *key, void **val, uint64_t *len);
API bool msgunpack_arr(uint64_t *len);
API bool msgunpack_map(uint64_t *len);
API bool msgunpack_eof();
API bool msgunpack_err();

// ----------------------------------------------------------------------------
// Based on code by Brian "Beej Jorgensen" Hall (public domain) [1].
// Based on code by Ginger Bill's half<->float (public domain) [2].
// - rlyeh, public domain.
//
// pack.c  -- perl/python-ish pack/unpack functions
// like printf and scanf, but for binary data.
//
// format flags:
//  (<) little endian       (>) big endian (! also)     (=) native endian
//  (c) 8-bit  char         (b) 8-bit  byte
//  (h) 16-bit half         (w) 16-bit word
//  (i) 32-bit integer      (u) 32-bit unsigned         (f) 32-bit float
//  (l) 64-bit long         (q) 64-bit quad             (d) 64-bit double
//  (v) varint
//  (s) string   (64-bit varint length prepended)
//  (S) string   (32-bit fixed  length prepended)
//  (m) memblock (64-bit varint length prepended)
//  (M) memblock (32-bit fixed  length prepended)
//  (z) memblock (zeroed)
//  (#) number of arguments processed (only when unpacking)
//
// @todo:
// - (x) document & test flag
// @totest:
// - (s) string   (64-bit variable length automatically prepended)
// - (S) string   (32-bit fixed    length automatically prepended)
// - (m) memblock (64-bit variable length automatically prepended)
// - (M) memblock (32-bit fixed    length automatically prepended)
// - (z) memblock (zeroed)
// - (#) number of arguments processed (only when unpacking)

// - save data dictated by the format string from the buffer. return: number of bytes written, or 0 if error.
//   if first argument is zero, returns number of bytes required for packing.

API int savef(FILE *file, const char *format, ...);
API int saveb(unsigned char *buf, const char *format, ...);

// - load data dictated by the format string into the buffer. return: number of bytes read, or 0 if error.
//   if first argument is zero, returns number of bytes required for unpacking.

API int loadf(FILE *file, const char *format, ...);
API int loadb(const unsigned char *buf, const char *format, ...);