xref: /trunk/main/sal/rtl/source/hash.cxx (revision cdf0e10c)
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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 }
114