1*1d2dbeb0SAndrew Rist /************************************************************** 2cdf0e10cSrcweir * 3*1d2dbeb0SAndrew Rist * Licensed to the Apache Software Foundation (ASF) under one 4*1d2dbeb0SAndrew Rist * or more contributor license agreements. See the NOTICE file 5*1d2dbeb0SAndrew Rist * distributed with this work for additional information 6*1d2dbeb0SAndrew Rist * regarding copyright ownership. The ASF licenses this file 7*1d2dbeb0SAndrew Rist * to you under the Apache License, Version 2.0 (the 8*1d2dbeb0SAndrew Rist * "License"); you may not use this file except in compliance 9*1d2dbeb0SAndrew Rist * with the License. You may obtain a copy of the License at 10*1d2dbeb0SAndrew Rist * 11*1d2dbeb0SAndrew Rist * http://www.apache.org/licenses/LICENSE-2.0 12*1d2dbeb0SAndrew Rist * 13*1d2dbeb0SAndrew Rist * Unless required by applicable law or agreed to in writing, 14*1d2dbeb0SAndrew Rist * software distributed under the License is distributed on an 15*1d2dbeb0SAndrew Rist * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 16*1d2dbeb0SAndrew Rist * KIND, either express or implied. See the License for the 17*1d2dbeb0SAndrew Rist * specific language governing permissions and limitations 18*1d2dbeb0SAndrew Rist * under the License. 19*1d2dbeb0SAndrew Rist * 20*1d2dbeb0SAndrew Rist *************************************************************/ 21*1d2dbeb0SAndrew Rist 22*1d2dbeb0SAndrew Rist 23cdf0e10cSrcweir #ifndef _STRINGHASH_HXX 24cdf0e10cSrcweir #define _STRINGHASH_HXX 25cdf0e10cSrcweir 26cdf0e10cSrcweir #include <tools/string.hxx> 27cdf0e10cSrcweir 28cdf0e10cSrcweir struct StringEq 29cdf0e10cSrcweir { operator ()StringEq30cdf0e10cSrcweir sal_Bool operator() ( const String *r1, 31cdf0e10cSrcweir const String *r2) const 32cdf0e10cSrcweir { 33cdf0e10cSrcweir return r1->Equals(*r2); 34cdf0e10cSrcweir } 35cdf0e10cSrcweir }; 36cdf0e10cSrcweir 37cdf0e10cSrcweir struct StringEqRef 38cdf0e10cSrcweir { operator ()StringEqRef39cdf0e10cSrcweir sal_Bool operator() (const String &r1, const String &r2) const 40cdf0e10cSrcweir { 41cdf0e10cSrcweir return r1.Equals(r2); 42cdf0e10cSrcweir } 43cdf0e10cSrcweir }; 44cdf0e10cSrcweir 45cdf0e10cSrcweir struct StringHash 46cdf0e10cSrcweir { operator ()StringHash47cdf0e10cSrcweir size_t operator() ( const String *rString) const 48cdf0e10cSrcweir { 49cdf0e10cSrcweir sal_Int32 h, nLen; 50cdf0e10cSrcweir h = nLen = rString->Len(); 51cdf0e10cSrcweir const sal_Unicode *pStr = rString->GetBuffer(); 52cdf0e10cSrcweir 53cdf0e10cSrcweir if ( nLen < 16 ) 54cdf0e10cSrcweir while ( nLen-- > 0 ) 55cdf0e10cSrcweir h = (h*37) + *(pStr++); 56cdf0e10cSrcweir else 57cdf0e10cSrcweir { 58cdf0e10cSrcweir sal_Int32 nSkip; 59cdf0e10cSrcweir const sal_Unicode* pEndStr = pStr+nLen-5; 60cdf0e10cSrcweir 61cdf0e10cSrcweir /* only sample some characters */ 62cdf0e10cSrcweir /* the first 3, some characters between, and the last 5 */ 63cdf0e10cSrcweir h = (h*39) + *(pStr++); 64cdf0e10cSrcweir h = (h*39) + *(pStr++); 65cdf0e10cSrcweir h = (h*39) + *(pStr++); 66cdf0e10cSrcweir 67cdf0e10cSrcweir nSkip = nLen / nLen < 32 ? 4 : 8; 68cdf0e10cSrcweir nLen -= 8; 69cdf0e10cSrcweir while ( nLen > 0 ) 70cdf0e10cSrcweir { 71cdf0e10cSrcweir h = (h*39) + ( *pStr ); 72cdf0e10cSrcweir pStr += nSkip; 73cdf0e10cSrcweir nLen -= nSkip; 74cdf0e10cSrcweir } 75cdf0e10cSrcweir 76cdf0e10cSrcweir h = (h*39) + *(pEndStr++); 77cdf0e10cSrcweir h = (h*39) + *(pEndStr++); 78cdf0e10cSrcweir h = (h*39) + *(pEndStr++); 79cdf0e10cSrcweir h = (h*39) + *(pEndStr++); 80cdf0e10cSrcweir h = (h*39) + *(pEndStr++); 81cdf0e10cSrcweir } 82cdf0e10cSrcweir return h; 83cdf0e10cSrcweir } 84cdf0e10cSrcweir operator ()StringHash85cdf0e10cSrcweir size_t operator() (const String & rStr) const 86cdf0e10cSrcweir { 87cdf0e10cSrcweir return (*this)(&rStr); 88cdf0e10cSrcweir } 89cdf0e10cSrcweir }; 90cdf0e10cSrcweir 91cdf0e10cSrcweir struct StringHashRef 92cdf0e10cSrcweir { operator ()StringHashRef93cdf0e10cSrcweir size_t operator () (const String &rStr) const 94cdf0e10cSrcweir { 95cdf0e10cSrcweir StringHash aStrHash; 96cdf0e10cSrcweir 97cdf0e10cSrcweir return aStrHash(&rStr); 98cdf0e10cSrcweir } 99cdf0e10cSrcweir }; 100cdf0e10cSrcweir #endif // _STRINGHASH_HXX 101