bind9/lib/isc/include/isc/bitstring.h
2000-02-03 23:08:31 +00:00

111 lines
2.6 KiB
C

/*
* Copyright (C) 1999, 2000 Internet Software Consortium.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
* ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
* CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
* DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
* PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
* ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
* SOFTWARE.
*/
#ifndef ISC_BITSTRING_H
#define ISC_BITSTRING_H 1
/*****
***** Module Info
*****/
/***
*** Imports
***/
#include <isc/lang.h>
#include <isc/types.h>
ISC_LANG_BEGINDECLS
/***
*** Types
***/
struct isc_bitstring {
unsigned int magic;
unsigned char * data;
unsigned int length;
unsigned int size;
isc_boolean_t lsb0;
};
/***
*** Functions
***/
void
isc_bitstring_init(isc_bitstring_t *bitstring, unsigned char *data,
unsigned int length, unsigned int size, isc_boolean_t lsb0);
/*
* Make 'bitstring' refer to the bitstring of 'size' bits starting
* at 'data'. 'length' bits of the bitstring are valid. If 'lsb0'
* is set then, bit 0 refers to the least significant bit of the
* bitstring. Otherwise bit 0 is the most significant bit.
*
* Requires:
*
* 'bitstring' points to a isc_bitstring_t.
*
* 'data' points to an array of unsigned char large enough to hold
* 'size' bits.
*
* 'length' <= 'size'.
*
* Ensures:
*
* 'bitstring' is a valid bitstring.
*/
void
isc_bitstring_invalidate(isc_bitstring_t *bitstring);
/*
* Invalidate 'bitstring'.
*
* Requires:
*
* 'bitstring' is a valid bitstring.
*
* Ensures:
*
* 'bitstring' is not a valid bitstring.
*/
void
isc_bitstring_copy(isc_bitstring_t *source, unsigned int sbitpos,
isc_bitstring_t *target, unsigned int tbitpos,
unsigned int n);
/*
* Starting at bit 'sbitpos', copy 'n' bits from 'source' to
* the 'n' bits of 'target' starting at 'tbitpos'.
*
* Requires:
*
* 'source' and target are valid bitstring.
*
* 'sbitpos' + 'n' is less than or equal to the length of 'source'.
*
* 'tbitpos' + 'n' is less than or equal to the size of 'target'.
*
* Ensures:
*
* The specified bits have been copied, and the length of 'target'
* adjusted (if required).
*/
ISC_LANG_ENDDECLS
#endif /* ISC_BITSTRING_H */