/* SPDX-License-Identifier: GPL-2.0 */

  /* Copyright (C) 2006-2019  B.A.T.M.A.N. contributors:

   *
   * Simon Wunderlich, Marek Lindner

   */
  
  #ifndef _NET_BATMAN_ADV_BITARRAY_H_
  #define _NET_BATMAN_ADV_BITARRAY_H_

  #include "main.h"
  
  #include <linux/bitops.h>
  #include <linux/compiler.h>

  #include <linux/stddef.h>

  #include <linux/types.h>

  /**

   * batadv_test_bit() - check if bit is set in the current window

   *
   * @seq_bits: pointer to the sequence number receive packet
   * @last_seqno: latest sequence number in seq_bits
   * @curr_seqno: sequence number to test for

   *

   * Return: true if the corresponding bit in the given seq_bits indicates true
   * and curr_seqno is within range of last_seqno. Otherwise returns false.

   */

  static inline bool batadv_test_bit(const unsigned long *seq_bits,
  				   u32 last_seqno, u32 curr_seqno)

  {

  	s32 diff;

  
  	diff = last_seqno - curr_seqno;

  	if (diff < 0 || diff >= BATADV_TQ_LOCAL_WINDOW_SIZE)

  		return false;

  	return test_bit(diff, seq_bits) != 0;

  }

  /**
   * batadv_set_bit() - Turn corresponding bit on, so we can remember that we got
   *  the packet
   * @seq_bits: bitmap of the packet receive window
   * @n: relative sequence number of newly received packet
   */

  static inline void batadv_set_bit(unsigned long *seq_bits, s32 n)

  {
  	/* if too old, just drop it */

  	if (n < 0 || n >= BATADV_TQ_LOCAL_WINDOW_SIZE)

  		return;

  	set_bit(n, seq_bits); /* turn the position on */
  }

  bool batadv_bit_get_packet(void *priv, unsigned long *seq_bits,
  			   s32 seq_num_diff, int set_mark);

  #endif /* _NET_BATMAN_ADV_BITARRAY_H_ */