48 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			48 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* ELLE - Copyright 1985, 1987 by Ken Harrenstien, SRI International
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|  *	This software is quasi-public; it may be used freely with
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|  *	like software, but may NOT be sold or made part of licensed
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|  *	products without permission of the author.
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|  */
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| /*
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|  * EEBIT	Bit Array functions
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|  */
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| #include "sb.h"
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| 
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| /* Char-bit array functions.   All assume that there are at least 8 bits
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|  * in a byte, and that the number of bytes per word is a power of 2.
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|  */
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| /* CHBBITS represents log 2 of the # of bits stored per chbit-array word.
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|  *	WDBITS already has log2 of the # of bytes per word, and we are
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|  *	assuming each byte has at least 8 bits, so log2(8) = 3.
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|  */
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| #define CHBSIZE (WDSIZE*8)	/* # bits per word */
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| #define CHBBITS (WDBITS+3)	/* log2(CHBSIZE) */
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| #define CHBMASK (CHBSIZE-1)
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| #define CHBARYSIZ (128/CHBSIZE)	/* # words per ASCII array */
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| 
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| /* CHBALLOC(size) - Allocates a char-bit array */
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| int *
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| chballoc(size)
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| int size;
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| {	return((int *)calloc((size + CHBSIZE-1)/CHBSIZE, (sizeof(int))));
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| }
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| 
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| /* CHBIT(array, char) - Tests bit in char-bit array
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|  */
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| chbit(array,c)
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| register int *array, c;
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| {	return(array[c >> CHBBITS] & (1 << (c & CHBMASK)));
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| }
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| /* CHBIS (array, char) - Sets bit in char-bit array
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|  */
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| chbis(array,c)
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| register int *array, c;
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| {	array[c >> CHBBITS] |= (1 << (c & CHBMASK));
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| }
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| /* CHBIC (array, char) - Clears bit in char-bit array
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|  */
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| chbic(array,c)
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| register int *array, c;
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| {	array[c >> CHBBITS] &= ~(1 << (c & CHBMASK));
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| }
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