1 /* Copyright (C) 2006-2015 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 /* Returns 1 if the corresponding bit in the given seq_bits indicates true 28 * and curr_seqno is within range of last_seqno. Otherwise returns 0. 29 */ 30 static inline int batadv_test_bit(const unsigned long *seq_bits, 31 uint32_t last_seqno, uint32_t curr_seqno) 32 { 33 int32_t diff; 34 35 diff = last_seqno - curr_seqno; 36 if (diff < 0 || diff >= BATADV_TQ_LOCAL_WINDOW_SIZE) 37 return 0; 38 return test_bit(diff, seq_bits) != 0; 39 } 40 41 /* turn corresponding bit on, so we can remember that we got the packet */ 42 static inline void batadv_set_bit(unsigned long *seq_bits, int32_t n) 43 { 44 /* if too old, just drop it */ 45 if (n < 0 || n >= BATADV_TQ_LOCAL_WINDOW_SIZE) 46 return; 47 48 set_bit(n, seq_bits); /* turn the position on */ 49 } 50 51 /* receive and process one packet, returns 1 if received seq_num is considered 52 * new, 0 if old 53 */ 54 int batadv_bit_get_packet(void *priv, unsigned long *seq_bits, 55 int32_t seq_num_diff, int set_mark); 56 57 #endif /* _NET_BATMAN_ADV_BITARRAY_H_ */ 58