64 lines
1.6 KiB
C++
64 lines
1.6 KiB
C++
/*
|
|
**********************************************************************
|
|
* Copyright (c) 2002-2004, 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 = (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 = (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
|