| 1 | /* Copyright (C) 2006-2016 B.A.T.M.A.N. contributors: |
| 2 | * |
| 3 | * Simon Wunderlich, Marek Lindner |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or |
| 6 | * modify it under the terms of version 2 of the GNU General Public |
| 7 | * License as published by the Free Software Foundation. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, but |
| 10 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | * General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License |
| 15 | * along with this program; if not, see <http://www.gnu.org/licenses/>. |
| 16 | */ |
| 17 | |
| 18 | #ifndef _NET_BATMAN_ADV_BITARRAY_H_ |
| 19 | #define _NET_BATMAN_ADV_BITARRAY_H_ |
| 20 | |
| 21 | #include "main.h" |
| 22 | |
| 23 | #include <linux/bitops.h> |
| 24 | #include <linux/compiler.h> |
| 25 | #include <linux/types.h> |
| 26 | |
| 27 | /** |
| 28 | * batadv_test_bit - check if bit is set in the current window |
| 29 | * |
| 30 | * @seq_bits: pointer to the sequence number receive packet |
| 31 | * @last_seqno: latest sequence number in seq_bits |
| 32 | * @curr_seqno: sequence number to test for |
| 33 | * |
| 34 | * Return: 1 if the corresponding bit in the given seq_bits indicates true |
| 35 | * and curr_seqno is within range of last_seqno. Otherwise returns 0. |
| 36 | */ |
| 37 | static inline int batadv_test_bit(const unsigned long *seq_bits, |
| 38 | u32 last_seqno, u32 curr_seqno) |
| 39 | { |
| 40 | s32 diff; |
| 41 | |
| 42 | diff = last_seqno - curr_seqno; |
| 43 | if (diff < 0 || diff >= BATADV_TQ_LOCAL_WINDOW_SIZE) |
| 44 | return 0; |
| 45 | return test_bit(diff, seq_bits) != 0; |
| 46 | } |
| 47 | |
| 48 | /* turn corresponding bit on, so we can remember that we got the packet */ |
| 49 | static inline void batadv_set_bit(unsigned long *seq_bits, s32 n) |
| 50 | { |
| 51 | /* if too old, just drop it */ |
| 52 | if (n < 0 || n >= BATADV_TQ_LOCAL_WINDOW_SIZE) |
| 53 | return; |
| 54 | |
| 55 | set_bit(n, seq_bits); /* turn the position on */ |
| 56 | } |
| 57 | |
| 58 | int batadv_bit_get_packet(void *priv, unsigned long *seq_bits, s32 seq_num_diff, |
| 59 | int set_mark); |
| 60 | |
| 61 | #endif /* _NET_BATMAN_ADV_BITARRAY_H_ */ |