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126 lines
4.3 KiB
C
126 lines
4.3 KiB
C
/*****************************************************************************/
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/* */
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/* bitops.c */
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/* */
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/* Single bit operations */
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/* */
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/* */
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/* */
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/* (C) 1998 Ullrich von Bassewitz */
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/* Wacholderweg 14 */
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/* D-70597 Stuttgart */
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/* EMail: uz@musoftware.de */
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/* */
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/* */
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/* This software is provided 'as-is', without any expressed or implied */
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/* warranty. In no event will the authors be held liable for any damages */
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/* arising from the use of this software. */
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/* */
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/* Permission is granted to anyone to use this software for any purpose, */
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/* including commercial applications, and to alter it and redistribute it */
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/* freely, subject to the following restrictions: */
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/* */
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/* 1. The origin of this software must not be misrepresented; you must not */
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/* claim that you wrote the original software. If you use this software */
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/* in a product, an acknowledgment in the product documentation would be */
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/* appreciated but is not required. */
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/* 2. Altered source versions must be plainly marked as such, and must not */
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/* be misrepresented as being the original software. */
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/* 3. This notice may not be removed or altered from any source */
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/* distribution. */
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/* */
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/*****************************************************************************/
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#include "bitops.h"
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/*****************************************************************************/
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/* Code */
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/*****************************************************************************/
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unsigned BitFind (unsigned long Val)
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/* Find the first bit that is set in Val. Val must *not* be zero */
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{
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unsigned long Mask;
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unsigned Bit;
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/* Search for the bits */
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Mask = 1;
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Bit = 0;
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while (1) {
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if (Val & Mask) {
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return Bit;
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}
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Mask <<= 1;
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++Bit;
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}
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}
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void BitSet (void* Data, unsigned Bit)
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/* Set a bit in a char array */
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{
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/* Make a char pointer */
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unsigned char* D = Data;
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/* Set the bit */
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D [Bit / 8] |= 0x01 << (Bit % 8);
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}
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void BitReset (void* Data, unsigned Bit)
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/* Reset a bit in a char array */
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{
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/* Make a char pointer */
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unsigned char* D = Data;
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/* Set the bit */
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D [Bit / 8] &= ~(0x01 << (Bit % 8));
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}
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int BitIsSet (void* Data, unsigned Bit)
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/* Check if a bit is set in a char array */
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{
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/* Make a char pointer */
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unsigned char* D = Data;
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/* Check the bit state */
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return (D [Bit / 8] & (0x01 << (Bit % 8))) != 0;
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}
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int BitIsReset (void* Data, unsigned Bit)
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/* Check if a bit is reset in a char array */
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{
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/* Make a char pointer */
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unsigned char* D = Data;
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/* Check the bit state */
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return (D [Bit / 8] & (0x01 << (Bit % 8))) == 0;
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}
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void BitMerge (void* Target, const void* Source, unsigned Size)
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/* Merge the bits of two char arrays (that is, do an or for the full array) */
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{
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/* Make char arrays */
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unsigned char* T = Target;
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const unsigned char* S = Source;
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/* Merge the arrays */
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while (Size--) {
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*T++ |= *S++;
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}
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}
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