1 /* Copyright (C) 2006-2017 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/stddef.h> 26 #include <linux/types.h> 27 28 /** 29 * batadv_test_bit - check if bit is set in the current window 30 * 31 * @seq_bits: pointer to the sequence number receive packet 32 * @last_seqno: latest sequence number in seq_bits 33 * @curr_seqno: sequence number to test for 34 * 35 * Return: true if the corresponding bit in the given seq_bits indicates true 36 * and curr_seqno is within range of last_seqno. Otherwise returns false. 37 */ 38 static inline bool batadv_test_bit(const unsigned long *seq_bits, 39 u32 last_seqno, u32 curr_seqno) 40 { 41 s32 diff; 42 43 diff = last_seqno - curr_seqno; 44 if (diff < 0 || diff >= BATADV_TQ_LOCAL_WINDOW_SIZE) 45 return false; 46 return test_bit(diff, seq_bits) != 0; 47 } 48 49 /* turn corresponding bit on, so we can remember that we got the packet */ 50 static inline void batadv_set_bit(unsigned long *seq_bits, s32 n) 51 { 52 /* if too old, just drop it */ 53 if (n < 0 || n >= BATADV_TQ_LOCAL_WINDOW_SIZE) 54 return; 55 56 set_bit(n, seq_bits); /* turn the position on */ 57 } 58 59 bool batadv_bit_get_packet(void *priv, unsigned long *seq_bits, 60 s32 seq_num_diff, int set_mark); 61 62 #endif /* _NET_BATMAN_ADV_BITARRAY_H_ */ 63