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/*
* Copyright (C) 1999-2001 Niels Provos <provos@citi.umich.edu>
* All rights reserved.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Niels Provos.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
#ifndef _ITERATOR_H
#define _ITERATOR_H
#define INIT_SKIPMOD 32
#define DEFAULT_ITER 256
/* Slowly fade skip out at the end of the picture */
#define SKIPADJ(x,y) ((y) > (x)/32 ? 2 : 2 - ((x/32) - (y))/(float)(x/32))
/*
* The generic iterator
*/
typedef struct _iterator {
struct arc4_stream as;
u_int32_t skipmod;
int off; /* Current bit position */
} iterator;
struct _bitmap;
void iterator_init(iterator *, struct _bitmap *, u_char *key, u_int klen);
int iterator_next(iterator *, struct _bitmap *);
#define ITERATOR_CURRENT(x) (x)->off
void iterator_seed(iterator *, struct _bitmap *, u_int16_t);
void iterator_adapt(iterator *, struct _bitmap *, int);
#endif
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