#ifndef RLV_MULTISTRINGSEARCH_H #define RLV_MULTISTRINGSEARCH_H // ============================================================================ // Template classes for our state machine (2 dimensional array of type T) // STL vector template class RlvMultiStringSearchFSM_STL { public: /* * Constructor/destructor */ // Initialize the FSM with an initial capacity of 'nCapacity' states RlvMultiStringSearchFSM_STL(size_t nCapacity) { m_arFSM.reserve(nCapacity); T* pT; for (size_t idx = 0; idx < nCapacity; idx++) { // The width of each row is determined by the alphabet we're using (in this case UTF-8 // so while every character might consist of multiple bytes there are // still only 256 'columns' in the state machine) pT = new T[256](); // The above *should* initialize to 0 but since we can't account for every compiler doing it :( memset(pT, 0, sizeof(T) * 256); m_arFSM.push_back(pT); } }; ~RlvMultiStringSearchFSM_STL() { // Free any memory we previously allocated for (int idx = 0, cnt = m_arFSM.size(); idx < cnt; idx++) delete[] m_arFSM[idx]; } /* * Operators */ // ASSERTION: nState < m_arFSM.size() at all times // In other words: do *NOT* go out of bounds on the array (no memory will have allocated for that non-existing state) // (There probably should be a check for that even in release but it seems wasteful, just don't do it :p) inline T* operator[](size_t nState) { //#ifdef _DEBUG // assert( nState < m_arFSM.size() ); //#endif // _DEBUG return m_arFSM[nState]; } inline const T* operator[](size_t nState) const { //#ifdef _DEBUG // assert( nState < m_arFSM.size() ); //#endif // _DEBUG return m_arFSM[nState]; } /* * Public member functions */ size_t getSize() const { return m_arFSM.size(); } void resize(size_t nNewCapacity) { // Get our current capacity (only rows > capacity need memory allocated) size_t nCurCapacity = m_arFSM.capacity(); // Only expand, never shrink if (nNewCapacity <= nCurCapacity) { //#ifdef _DEBUG // assert(false); //#endif //_DEBUG return; } m_arFSM.resize(nNewCapacity); // For each new state we added, allocate memory for the columns for(size_t idx = nCurCapacity; idx < nNewCapacity; idx++) // The memset is redundant (or rather *should* be) but since we can't account for every compiler doing it :( m_arFSM[idx] = (T*)memset(new T[256](), 0, sizeof(T) * 256); } protected: /* * Member variables */ std::vector m_arFSM; }; // ============================================================================ struct RlvMultiStringSearchMatch { int idxMatch; // Starting character index into the string of the matched keyword (-1 if no match) int lenMatch; // Length of the matched keyword (undefined if no match) U16 nParam; // User supplied parameter for the matched keyword (undefined if no match) RlvMultiStringSearchMatch() : idxMatch(-1) {} }; // ============================================================================ // The actual search class class RlvMultiStringSearch { public: /* * Constructor/destructor */ RlvMultiStringSearch(); //~RlvMultiStringSearch(); /* * Public member functions */ // Add a keyword to the state machine (if it already exists then it will simply overwrite the existing parameter) void addKeyword(const std::string& strKeyword, U16 nParam); BOOL getExactMatchParam(const std::string& strText, U16& nParam) const { RlvMultiStringSearchMatch match; if (findFirst(strText, match)) { // We have an exact match if the starting index is 0 // and the length of the match matches the length of the string if ( (0 == match.idxMatch) && (match.lenMatch == (int)strText.length()) ) { nParam = match.nParam; return TRUE; } } return FALSE; // Fall-through: no (exact) match } // Finds the first occurance of any keyword in the supplied string bool findFirst(const std::string& strText, RlvMultiStringSearchMatch& match) const; // Finds the next occurance of any keyword in the supplied string bool findNext(const std::string& strText, int idxCh, RlvMultiStringSearchMatch& match) const; // Finds all occurances of any keyword in the supplied string std::vector findAll(const std::string& strText); // Finds the last occurance of any keyword in the supplied string (non-optimized) bool findLast(const std::string& strText, RlvMultiStringSearchMatch& match) const; protected: // Finds the next occurance of any keyword in the supplied string bool findNext(const char* pstrText, int idxCh, int cntCh, RlvMultiStringSearchMatch& match, bool fWordMatch = true) const; /* * Member variables */ RlvMultiStringSearchFSM_STL m_FSM; // Our finite state machine (4 bytes * 256 = 1Kb of memory/state) // HIWORD(U32) = 16-bits of user data // LOWORD(U32) = ABBBBBBBBBBBBBBB // A = termination bit // If (set) and (B == 0): match // If (set) and (B != 0): match, but might only be a substring of another keyword // B = next state (0..32767) // If (B == 0): false lead -> backtrack // If (B != 0): partial keyword match, next state size_t m_cntState; // The number of states in the FSM (= the number of *used* rows in the array) }; // ============================================================================ // Inlined member functions // inline bool RlvMultiStringSearch::findFirst(const std::string& strText, RlvMultiStringSearchMatch& match) const { return findNext(strText.c_str(), 0, strText.length(), match); } inline bool RlvMultiStringSearch::findNext(const std::string& strText, int idxCh, RlvMultiStringSearchMatch& match) const { return findNext(strText.c_str(), idxCh, strText.length(), match); } // ============================================================================ #endif // RLV_MULTISTRINGSEARCH_H