Add new <bsd/sys/bitstring.h> header

Taken from FreeBSD.

1 files changed, 146 insertions, 0 deletions

diff --git a/include/bsd/sys/bitstring.h b/include/bsd/sys/bitstring.h
new file mode 100644
index 0000000..125ef51
--- /dev/null
+++ b/include/bsd/sys/bitstring.h
@@ -0,0 +1,146 @@
+/*-
+ * Copyright (c) 1989, 1993
+ *	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, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _SYS_BITSTRING_H_
+#define	_SYS_BITSTRING_H_
+
+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) do { \
+	register bitstr_t *_name = (name); \
+	register int _start = (start), _stop = (stop); \
+	register int _startbyte = _bit_byte(_start); \
+	register int _stopbyte = _bit_byte(_stop); \
+	if (_startbyte == _stopbyte) { \
+		_name[_startbyte] &= ((0xff >> (8 - (_start&0x7))) | \
+				      (0xff << ((_stop&0x7) + 1))); \
+	} else { \
+		_name[_startbyte] &= 0xff >> (8 - (_start&0x7)); \
+		while (++_startbyte < _stopbyte) \
+			_name[_startbyte] = 0; \
+		_name[_stopbyte] &= 0xff << ((_stop&0x7) + 1); \
+	} \
+} while (0)
+
+				/* set bits start ... stop in bitstring */
+#define	bit_nset(name, start, stop) do { \
+	register bitstr_t *_name = (name); \
+	register int _start = (start), _stop = (stop); \
+	register int _startbyte = _bit_byte(_start); \
+	register int _stopbyte = _bit_byte(_stop); \
+	if (_startbyte == _stopbyte) { \
+		_name[_startbyte] |= ((0xff << (_start&0x7)) & \
+				    (0xff >> (7 - (_stop&0x7)))); \
+	} else { \
+		_name[_startbyte] |= 0xff << ((_start)&0x7); \
+		while (++_startbyte < _stopbyte) \
+	    		_name[_startbyte] = 0xff; \
+		_name[_stopbyte] |= 0xff >> (7 - (_stop&0x7)); \
+	} \
+} while (0)
+
+				/* find first bit clear in name */
+#define	bit_ffc(name, nbits, value) do { \
+	register bitstr_t *_name = (name); \
+	register int _byte, _nbits = (nbits); \
+	register int _stopbyte = _bit_byte(_nbits - 1), _value = -1; \
+	if (_nbits > 0) \
+		for (_byte = 0; _byte <= _stopbyte; ++_byte) \
+			if (_name[_byte] != 0xff) { \
+				bitstr_t _lb; \
+				_value = _byte << 3; \
+				for (_lb = _name[_byte]; (_lb&0x1); \
+				    ++_value, _lb >>= 1); \
+				break; \
+			} \
+	if (_value >= nbits) \
+		_value = -1; \
+	*(value) = _value; \
+} while (0)
+
+				/* find first bit set in name */
+#define	bit_ffs(name, nbits, value) do { \
+	register bitstr_t *_name = (name); \
+	register int _byte, _nbits = (nbits); \
+	register int _stopbyte = _bit_byte(_nbits - 1), _value = -1; \
+	if (_nbits > 0) \
+		for (_byte = 0; _byte <= _stopbyte; ++_byte) \
+			if (_name[_byte]) { \
+				bitstr_t _lb; \
+				_value = _byte << 3; \
+				for (_lb = _name[_byte]; !(_lb&0x1); \
+				    ++_value, _lb >>= 1); \
+				break; \
+			} \
+	if (_value >= nbits) \
+		_value = -1; \
+	*(value) = _value; \
+} while (0)
+
+#endif /* !_SYS_BITSTRING_H_ */