1 /* 2 * Copyright (c) 1998-2001 Sendmail, Inc. and its suppliers. 3 * All rights reserved. 4 * Copyright (c) 1983, 1995-1997 Eric P. Allman. All rights reserved. 5 * Copyright (c) 1988, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * By using this file, you agree to the terms and conditions set 9 * forth in the LICENSE file which can be found at the top level of 10 * the sendmail distribution. 11 * 12 * 13 * $Id: bitops.h,v 1.2 2001/09/22 22:05:42 ca Exp $ 14 */ 15 16 #ifndef SM_BITOPS_H 17 # define SM_BITOPS_H 18 19 /* 20 ** Data structure for bit maps. 21 ** 22 ** Each bit in this map can be referenced by an ascii character. 23 ** This is 256 possible bits, or 32 8-bit bytes. 24 */ 25 26 # define BITMAPBITS 256 /* number of bits in a bit map */ 27 # define BYTEBITS 8 /* number of bits in a byte */ 28 # define BITMAPBYTES (BITMAPBITS / BYTEBITS) /* number of bytes in bit map */ 29 # define BITMAPMAX ((BITMAPBYTES / sizeof (int)) - 1) 30 31 /* internal macros */ 32 33 /* make sure this index never leaves the allowed range: 0 to BITMAPMAX */ 34 # define _BITWORD(bit) (((unsigned char)(bit) / (BYTEBITS * sizeof (int))) & BITMAPMAX) 35 # define _BITBIT(bit) ((unsigned int)1 << ((unsigned char)(bit) % (BYTEBITS * sizeof (int)))) 36 37 typedef unsigned int BITMAP256[BITMAPBYTES / sizeof (int)]; 38 39 /* properly case and truncate bit */ 40 # define bitidx(bit) ((unsigned int) (bit) & 0xff) 41 42 /* test bit number N */ 43 # define bitnset(bit, map) ((map)[_BITWORD(bit)] & _BITBIT(bit)) 44 45 /* set bit number N */ 46 # define setbitn(bit, map) (map)[_BITWORD(bit)] |= _BITBIT(bit) 47 48 /* clear bit number N */ 49 # define clrbitn(bit, map) (map)[_BITWORD(bit)] &= ~_BITBIT(bit) 50 51 /* clear an entire bit map */ 52 # define clrbitmap(map) memset((char *) map, '\0', BITMAPBYTES) 53 54 /* bit hacking */ 55 # define bitset(bit, word) (((word) & (bit)) != 0) 56 57 #endif /* ! SM_BITOPS_H */ 58