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authorTheo de Raadt <deraadt@cvs.openbsd.org>1995-10-18 08:53:40 +0000
committerTheo de Raadt <deraadt@cvs.openbsd.org>1995-10-18 08:53:40 +0000
commitd6583bb2a13f329cf0332ef2570eb8bb8fc0e39c (patch)
treeece253b876159b39c620e62b6c9b1174642e070e /include/bitstring.h
initial import of NetBSD tree
Diffstat (limited to 'include/bitstring.h')
-rw-r--r--include/bitstring.h115
1 files changed, 115 insertions, 0 deletions
diff --git a/include/bitstring.h b/include/bitstring.h
new file mode 100644
index 00000000000..5966a1d3f5d
--- /dev/null
+++ b/include/bitstring.h
@@ -0,0 +1,115 @@
+/* $NetBSD: bitstring.h,v 1.4 1994/10/26 00:55:45 cgd Exp $ */
+
+/*
+ * Copyright (c) 1989 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Paul Vixie.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by the University of California, Berkeley. The name of the
+ * University may not be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * @(#)bitstring.h 5.2 (Berkeley) 4/4/90
+ */
+
+#ifndef _BITSTRING_H_
+#define _BITSTRING_H_
+
+/* modified for SV/AT and bitstring bugfix by M.R.Murphy, 11oct91
+ * bitstr_size changed gratuitously, but shorter
+ * bit_alloc spelling error fixed
+ * the following were efficient, but didn't work, they've been made to
+ * work, but are no longer as efficient :-)
+ * bit_nclear, bit_nset, bit_ffc, bit_ffs
+ */
+typedef unsigned char bitstr_t;
+
+/* internal macros */
+ /* byte of the bitstring bit is in */
+#define _bit_byte(bit) \
+ ((bit) >> 3)
+
+ /* mask for the bit within its byte */
+#define _bit_mask(bit) \
+ (1 << ((bit)&0x7))
+
+/* external macros */
+ /* bytes in a bitstring of nbits bits */
+#define bitstr_size(nbits) \
+ (((nbits) + 7) >> 3)
+
+ /* allocate a bitstring */
+#define bit_alloc(nbits) \
+ (bitstr_t *)calloc((size_t)bitstr_size(nbits), sizeof(bitstr_t))
+
+ /* allocate a bitstring on the stack */
+#define bit_decl(name, nbits) \
+ (name)[bitstr_size(nbits)]
+
+ /* is bit N of bitstring name set? */
+#define bit_test(name, bit) \
+ ((name)[_bit_byte(bit)] & _bit_mask(bit))
+
+ /* set bit N of bitstring name */
+#define bit_set(name, bit) \
+ (name)[_bit_byte(bit)] |= _bit_mask(bit)
+
+ /* clear bit N of bitstring name */
+#define bit_clear(name, bit) \
+ (name)[_bit_byte(bit)] &= ~_bit_mask(bit)
+
+ /* clear bits start ... stop in bitstring */
+#define bit_nclear(name, start, stop) { \
+ register bitstr_t *_name = name; \
+ register int _start = start, _stop = stop; \
+ while (_start <= _stop) { \
+ bit_clear(_name, _start); \
+ _start++; \
+ } \
+}
+
+ /* set bits start ... stop in bitstring */
+#define bit_nset(name, start, stop) { \
+ register bitstr_t *_name = name; \
+ register int _start = start, _stop = stop; \
+ while (_start <= _stop) { \
+ bit_set(_name, _start); \
+ _start++; \
+ } \
+}
+
+ /* find first bit clear in name */
+#define bit_ffc(name, nbits, value) { \
+ register bitstr_t *_name = name; \
+ register int _bit, _nbits = nbits, _value = -1; \
+ for (_bit = 0; _bit < _nbits; ++_bit) \
+ if (!bit_test(_name, _bit)) { \
+ _value = _bit; \
+ break; \
+ } \
+ *(value) = _value; \
+}
+
+ /* find first bit set in name */
+#define bit_ffs(name, nbits, value) { \
+ register bitstr_t *_name = name; \
+ register int _bit, _nbits = nbits, _value = -1; \
+ for (_bit = 0; _bit < _nbits; ++_bit) \
+ if (bit_test(_name, _bit)) { \
+ _value = _bit; \
+ break; \
+ } \
+ *(value) = _value; \
+}
+
+#endif /* !_BITSTRING_H_ */