//-------------------------------------------------------------------- // An example of how to create a wrapper for CLKRHashTable //-------------------------------------------------------------------- #include #ifndef __LKRHASH_NO_NAMESPACE__ #define LKRHASH_NS LKRhash // using namespace LKRhash; #else // __LKRHASH_NO_NAMESPACE__ #define LKRHASH_NS #endif // __LKRHASH_NO_NAMESPACE__ #ifndef __HASHFN_NO_NAMESPACE__ #define HASHFN_NS HashFn // using namespace HashFn; #else // __HASHFN_NO_NAMESPACE__ #define HASHFN_NS #endif // __HASHFN_NO_NAMESPACE__ // some random class class CTest { public: enum {BUFFSIZE=20}; int m_n; // This will also be a key char m_sz[BUFFSIZE]; // This will be the primary key bool m_fWhatever; mutable LONG m_cRefs; // Reference count for lifetime management. // Must be mutable to use 'const CTest*' in // hashtables CTest(int n, const char* psz, bool f) : m_n(n), m_fWhatever(f), m_cRefs(0) { strncpy(m_sz, psz, BUFFSIZE-1); m_sz[BUFFSIZE-1] = '\0'; } ~CTest() { IRTLASSERT(m_cRefs == 0); } }; // A typed hash table of CTests, keyed on the string field. Case-insensitive. class CStringTestHashTable : public LKRHASH_NS::CTypedHashTable { public: CStringTestHashTable() : LKRHASH_NS::CTypedHashTable("string", LK_DFLT_MAXLOAD, LK_SMALL_TABLESIZE, LK_DFLT_NUM_SUBTBLS) {} static const char* ExtractKey(const CTest* pTest) { return pTest->m_sz; } static DWORD CalcKeyHash(const char* pszKey) { return HASHFN_NS::HashStringNoCase(pszKey); } static bool EqualKeys(const char* pszKey1, const char* pszKey2) { return _stricmp(pszKey1, pszKey2) == 0; } static void AddRefRecord(const CTest* pTest, LK_ADDREF_REASON lkar) { if (lkar > 0) { // or, perhaps, pIFoo->AddRef() (watch out for marshalling) // or ++pTest->m_cRefs (single-threaded only) InterlockedIncrement(&pTest->m_cRefs); } else if (lkar < 0) { // or, perhaps, pIFoo->Release() or --pTest->m_cRefs; LONG l = InterlockedDecrement(&pTest->m_cRefs); // For some hashtables, it may also make sense to add the following // if (l == 0) delete pTest; // but that would typically only apply when InsertRecord was // used thus // lkrc = ht.InsertRecord(new CTest(foo, bar)); } else IRTLASSERT(0); IRTLTRACE("AddRef(%p, %s) %d, cRefs == %d\n", pTest, pTest->m_sz, lkar, pTest->m_cRefs); } }; // Another typed hash table of CTests. This one is keyed on the numeric field. class CNumberTestHashTable : public LKRHASH_NS::CTypedHashTable { public: CNumberTestHashTable() : LKRHASH_NS::CTypedHashTable( "number") {} static int ExtractKey(const CTest* pTest) {return pTest->m_n;} static DWORD CalcKeyHash(int nKey) {return HASHFN_NS::Hash(nKey);} static bool EqualKeys(int nKey1, int nKey2) {return nKey1 == nKey2;} static void AddRefRecord(const CTest* pTest, LK_ADDREF_REASON lkar) { int nIncr = (lkar > 0) ? +1 : -1; InterlockedExchangeAdd(&pTest->m_cRefs, nIncr); IRTLTRACE("AddRef(%p, %d) %d (%d), cRefs == %d\n", pTest, pTest->m_n, nIncr, (int) lkar, pTest->m_cRefs); } };