/*
DESCRIPTION
  helpers.h defines some structs and function signatures that will help to
  interface with C code used in our fuzz testing. 

AUTHORS
  Saxon A. Nelson-Milton <saxon@ausocean.org>

LICENSE
  Copyright (C) 2019 the Australian Ocean Lab (AusOcean).

  It is free software: you can redistribute it and/or modify them
  under the terms of the GNU General Public License as published by the
  Free Software Foundation, either version 3 of the License, or (at your
  option) any later version.

  It is distributed in the hope that it will be useful, but WITHOUT
  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  for more details.

  You should have received a copy of the GNU General Public License
  in gpl.txt.  If not, see http://www.gnu.org/licenses.
*/

#ifndef HELPERS_H
#define HELPERS_H

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

struct Reader {
  char* data;
  int   curr;
  int   len;
  int   err;
};

struct BitReader {
  struct Reader*  r;
  uint64_t        n;
  int             bits;
  int             nRead;
  int             err;
};

// new_BitReader returns a new instance of a BitReader given the backing array
// d and the length of the data l.
struct BitReader* new_BitReader(char*, int);

// next_byte provides the next byte from a Reader r and advances it's byte index.
char next_byte(struct Reader*);

// read_bits intends to emulate the BitReader.ReadBits function defined in the
// bits package. This is used when a bit reader is required to obtain bytes from
// a stream in the C test code.
uint64_t read_bits(struct BitReader*, int);

#endif // HELPERS_H