#ifndef BIPBUFFER_H

#define BIPBUFFER_H

typedef struct

{

    unsigned long int size;

    /* region A */

    unsigned int a_start, a_end;

    /* region B */

    unsigned int b_end;

    /* is B inuse? */

    int b_inuse;

    unsigned char data[];

} bipbuf_t;

/**

 * Create a new bip buffer.

 *

 * malloc()s space

 *

 * @param[in] size The size of the buffer */

bipbuf_t *bipbuf_new(const unsigned int size);

/**

 * Initialise a bip buffer. Use memory provided by user.

 *

 * No malloc()s are performed.

 *

 * @param[in] size The size of the array */

void bipbuf_init(bipbuf_t* me, const unsigned int size);

/**

 * Free the bip buffer */

void bipbuf_free(bipbuf_t *me);

/* TODO: DOCUMENTATION */

unsigned char *bipbuf_request(bipbuf_t* me, const int size);

int bipbuf_push(bipbuf_t* me, const int size);

/**

 * @param[in] data The data to be offered to the buffer

 * @param[in] size The size of the data to be offered

 * @return number of bytes offered */

int bipbuf_offer(bipbuf_t *me, const unsigned char *data, const int size);

/**

 * Look at data. Don't move cursor

 *

 * @param[in] len The length of the data to be peeked

 * @return data on success, NULL if we can't peek at this much data */

unsigned char *bipbuf_peek(const bipbuf_t* me, const unsigned int len);

/**

 * Look at data. Don't move cursor

 *

 * @param[in] len The length of the data returned

 * @return data on success, NULL if nothing available */

unsigned char *bipbuf_peek_all(const bipbuf_t* me, unsigned int *len);

/**

 * Get pointer to data to read. Move the cursor on.

 *

 * @param[in] len The length of the data to be polled

 * @return pointer to data, NULL if we can't poll this much data */

unsigned char *bipbuf_poll(bipbuf_t* me, const unsigned int size);

/**

 * @return the size of the bipbuffer */

int bipbuf_size(const bipbuf_t* me);

/**

 * @return 1 if buffer is empty; 0 otherwise */

int bipbuf_is_empty(const bipbuf_t* me);

/**

 * @return how much space we have assigned */

int bipbuf_used(const bipbuf_t* cb);

/**

 * @return bytes of unused space */

int bipbuf_unused(const bipbuf_t* me);

#endif /* BIPBUFFER_H */