sal/rtl/source/hash.cxx

   1 /*************************************************************************
   2  *
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * Copyright 2000, 2010 Oracle and/or its affiliates.
   6  *
   7  * OpenOffice.org - a multi-platform office productivity suite
   8  *
   9  * This file is part of OpenOffice.org.
  10  *
  11  * OpenOffice.org is free software: you can redistribute it and/or modify
  12  * it under the terms of the GNU Lesser General Public License version 3
  13  * only, as published by the Free Software Foundation.
  14  *
  15  * OpenOffice.org is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU Lesser General Public License version 3 for more details
  19  * (a copy is included in the LICENSE file that accompanied this code).
  20  *
  21  * You should have received a copy of the GNU Lesser General Public License
  22  * version 3 along with OpenOffice.org.  If not, see
  23  * <http://www.openoffice.org/license.html>
  24  * for a copy of the LGPLv3 License.
  25  *
  26  ************************************************************************/
  27
  28 // MARKER(update_precomp.py): autogen include statement, do not remove
  29 #include "precompiled_sal.hxx"
  30 #include "rtl/allocator.hxx"
  31
  32 #include "hash.h"
  33 #include "strimp.h"
  34
  35
  36 #include <hash_set>
  37
  38 namespace {
  39
  40 struct UStringHash
  41 {
  42     size_t operator()(rtl_uString * const &rString) const
  43     { return (size_t)rtl_ustr_hashCode_WithLength( rString->buffer, rString->length ); }
  44 };
  45
  46 struct UStringEqual
  47 {
  48     sal_Bool operator() ( rtl_uString * const &pStringA,
  49                           rtl_uString * const &pStringB) const
  50     {
  51         if (pStringA == pStringB)
  52             return true;
  53         if (pStringA->length != pStringB->length)
  54             return false;
  55         return !rtl_ustr_compare_WithLength( pStringA->buffer, pStringA->length,
  56                                              pStringB->buffer, pStringB->length);
  57     }
  58 };
  59
  60 typedef std::hash_set< rtl_uString *, UStringHash, UStringEqual,
  61                        rtl::Allocator<rtl_uString *> > StringHashTable;
  62
  63 StringHashTable *
  64 getHashTable ()
  65 {
  66     static StringHashTable *pInternPool = NULL;
  67     if (pInternPool == NULL) {
  68         static StringHashTable aImpl(1024);
  69         pInternPool = &aImpl;
  70     }
  71     return pInternPool;
  72 }
  73
  74 }
  75
  76 extern "C" {
  77
  78 rtl_uString *
  79 rtl_str_hash_intern (rtl_uString       *pString,
  80                      int                can_return)
  81 {
  82     StringHashTable *pHash = getHashTable();
  83     StringHashTable::iterator aIter;
  84     aIter = pHash->find(pString);
  85     if (aIter != pHash->end())
  86     {
  87         rtl_uString *pHashStr = *aIter;
  88         rtl_uString_acquire (pHashStr);
  89         return pHashStr;
  90     }
  91     if (!can_return)
  92     {
  93         rtl_uString *pCopy = NULL;
  94         rtl_uString_newFromString( &pCopy, pString );
  95         pString = pCopy;
  96         if (!pString)
  97             return NULL;
  98     }
  99
 100     if (!SAL_STRING_IS_STATIC (pString))
 101         pString->refCount |= SAL_STRING_INTERN_FLAG;
 102     pHash->insert(pString);
 103
 104     return pString;
 105 }
 106
 107 void
 108 rtl_str_hash_remove (rtl_uString       *pString)
 109 {
 110     getHashTable()->erase(pString);
 111 }
 112
 113 }