1 /* 2 *********************************************************************** 3 * Copyright (C) 2016 and later: Unicode, Inc. and others. 4 * License & terms of use: http://www.unicode.org/copyright.html#License 5 *********************************************************************** 6 *********************************************************************** 7 * Copyright (c) 2002-2005, International Business Machines 8 * Corporation and others. All Rights Reserved. 9 *********************************************************************** 10 * 2002-09-20 aliu Created. 11 */ 12 13 #include "unicode/utypes.h" 14 #include "cmemory.h" 15 #include "bitset.h" 16 17 // TODO: have a separate capacity, so the len can just be set to 18 // zero in the clearAll() method, and growth can be smarter. 19 20 const int32_t SLOP = 8; 21 22 const int32_t BYTES_PER_WORD = sizeof(int32_t); 23 24 BitSet::BitSet() { 25 len = SLOP; 26 data = (int32_t*) uprv_malloc(len * BYTES_PER_WORD); 27 clearAll(); 28 } 29 30 BitSet::~BitSet() { 31 uprv_free(data); 32 } 33 34 UBool BitSet::get(int32_t bitIndex) const { 35 uint32_t longIndex = bitIndex >> 5; 36 int32_t bitInLong = bitIndex & 0x1F; 37 return (longIndex < len) ? (((data[longIndex] >> bitInLong) & 1) != 0) 38 : FALSE; 39 } 40 41 void BitSet::set(int32_t bitIndex) { 42 uint32_t longIndex = bitIndex >> 5; 43 int32_t bitInLong = bitIndex & 0x1F; 44 if (longIndex >= len) { 45 ensureCapacity(longIndex+1); 46 } 47 data[longIndex] |= (1 << bitInLong); 48 } 49 50 void BitSet::clearAll() { 51 for (uint32_t i=0; i<len; ++i) data[i] = 0; 52 } 53 54 void BitSet::ensureCapacity(uint32_t minLen) { 55 uint32_t newLen = len; 56 while (newLen < minLen) newLen <<= 1; // grow exponentially 57 int32_t* newData = (int32_t*) uprv_malloc(newLen * BYTES_PER_WORD); 58 uprv_memcpy(newData, data, len * BYTES_PER_WORD); 59 uprv_free(data); 60 data = newData; 61 int32_t* p = data + len; 62 int32_t* limit = data + newLen; 63 while (p < limit) *p++ = 0; 64 len = newLen; 65 } 66 67 //eof 68
