#include <stddef.h>
#include <stdint.h>


enum blake2b_constant
{
  BLAKE2B_BLOCKBYTES = 128,
  BLAKE2B_OUTBYTES   = 64,
  BLAKE2B_KEYBYTES   = 64,
  BLAKE2B_SALTBYTES  = 16,
  BLAKE2B_PERSONALBYTES = 16
};

typedef struct {
    uint8_t  b[128]; // input buffer
    uint64_t h[8];   // chained state
    uint64_t t[2];   // total number of bytes
    size_t   c;      // pointer for b[]
    size_t   outlen; // digest size
} blake2b_ctx;

void blake2b_update(blake2b_ctx *ctx, const void *in, size_t inlen);
int blake2b_init(blake2b_ctx *ctx, size_t outlen);
void blake2b_final(blake2b_ctx *ctx, void *out);