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/*
***********************************************************************
* © 2016 and later: Unicode, Inc. and others.
* License & terms of use: http://www.unicode.org/copyright.html
***********************************************************************
***********************************************************************
* Copyright (c) 2002-2005, International Business Machines
* Corporation and others. All Rights Reserved.
***********************************************************************
* 2002-09-20 aliu Created.
*/
#include "unicode/utypes.h"
#include "cmemory.h"
#include "bitset.h"
// TODO: have a separate capacity, so the len can just be set to
// zero in the clearAll() method, and growth can be smarter.
const int32_t SLOP = 8;
const int32_t BYTES_PER_WORD = sizeof(int32_t);
BitSet::BitSet() {
len = SLOP;
data = static_cast<int32_t*>(uprv_malloc(len * BYTES_PER_WORD));
clearAll();
}
BitSet::~BitSet() {
uprv_free(data);
}
UBool BitSet::get(int32_t bitIndex) const {
uint32_t longIndex = bitIndex >> 5;
int32_t bitInLong = bitIndex & 0x1F;
return (longIndex < len) ? (((data[longIndex] >> bitInLong) & 1) != 0)
: false;
}
void BitSet::set(int32_t bitIndex) {
uint32_t longIndex = bitIndex >> 5;
int32_t bitInLong = bitIndex & 0x1F;
if (longIndex >= len) {
ensureCapacity(longIndex+1);
}
data[longIndex] |= (1 << bitInLong);
}
void BitSet::clearAll() {
for (uint32_t i=0; i<len; ++i) data[i] = 0;
}
void BitSet::ensureCapacity(uint32_t minLen) {
uint32_t newLen = len;
while (newLen < minLen) newLen <<= 1; // grow exponentially
int32_t* newData = static_cast<int32_t*>(uprv_malloc(newLen * BYTES_PER_WORD));
uprv_memcpy(newData, data, len * BYTES_PER_WORD);
uprv_free(data);
data = newData;
int32_t* p = data + len;
int32_t* limit = data + newLen;
while (p < limit) *p++ = 0;
len = newLen;
}
//eof
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