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 #pragma ident "%Z%%M% %I% %E% SMI" 17 18 #ifndef SM_BITOPS_H 19 # define SM_BITOPS_H 20 21 /* 22 ** Data structure for bit maps. 23 ** 24 ** Each bit in this map can be referenced by an ascii character. 25 ** This is 256 possible bits, or 32 8-bit bytes. 26 */ 27 28 # define BITMAPBITS 256 /* number of bits in a bit map */ 29 # define BYTEBITS 8 /* number of bits in a byte */ 30 # define BITMAPBYTES (BITMAPBITS / BYTEBITS) /* number of bytes in bit map */ 31 # define BITMAPMAX ((BITMAPBYTES / sizeof (int)) - 1) 32 33 /* internal macros */ 34 35 /* make sure this index never leaves the allowed range: 0 to BITMAPMAX */ 36 # define _BITWORD(bit) (((unsigned char)(bit) / (BYTEBITS * sizeof (int))) & BITMAPMAX) 37 # define _BITBIT(bit) ((unsigned int)1 << ((unsigned char)(bit) % (BYTEBITS * sizeof (int)))) 38 39 typedef unsigned int BITMAP256[BITMAPBYTES / sizeof (int)]; 40 41 /* properly case and truncate bit */ 42 # define bitidx(bit) ((unsigned int) (bit) & 0xff) 43 44 /* test bit number N */ 45 # define bitnset(bit, map) ((map)[_BITWORD(bit)] & _BITBIT(bit)) 46 47 /* set bit number N */ 48 # define setbitn(bit, map) (map)[_BITWORD(bit)] |= _BITBIT(bit) 49 50 /* clear bit number N */ 51 # define clrbitn(bit, map) (map)[_BITWORD(bit)] &= ~_BITBIT(bit) 52 53 /* clear an entire bit map */ 54 # define clrbitmap(map) memset((char *) map, '\0', BITMAPBYTES) 55 56 /* bit hacking */ 57 # define bitset(bit, word) (((word) & (bit)) != 0) 58 59 #endif /* ! SM_BITOPS_H */ 60