| 1 | #ifndef INC_CircularQueue_hpp__ | 
| 2 | #define INC_CircularQueue_hpp__ | 
| 3 |  | 
| 4 | /* ANTLR Translator Generator | 
| 5 | * Project led by Terence Parr at http://www.jGuru.com | 
| 6 | * Software rights: http://www.antlr.org/license.html | 
| 7 | * | 
| 8 | * $Id: CircularQueue.hpp,v 1.1 2005-12-02 15:38:02 tim Exp $ | 
| 9 | */ | 
| 10 |  | 
| 11 | #include <antlr/config.hpp> | 
| 12 | #include <antlr/Token.hpp> | 
| 13 | #include <vector> | 
| 14 | #include <cassert> | 
| 15 |  | 
| 16 | #ifdef ANTLR_CXX_SUPPORTS_NAMESPACE | 
| 17 | namespace antlr { | 
| 18 | #endif | 
| 19 |  | 
| 20 | // Resize every 5000 items | 
| 21 | #define OFFSET_MAX_RESIZE 5000 | 
| 22 |  | 
| 23 | template <class T> | 
| 24 | class ANTLR_API CircularQueue { | 
| 25 | public: | 
| 26 | CircularQueue() | 
| 27 | : storage() | 
| 28 | , m_offset(0) | 
| 29 | { | 
| 30 | } | 
| 31 | ~CircularQueue() | 
| 32 | { | 
| 33 | } | 
| 34 |  | 
| 35 | /// Clear the queue | 
| 36 | inline void clear( void ) | 
| 37 | { | 
| 38 | m_offset = 0; | 
| 39 | storage.clear(); | 
| 40 | } | 
| 41 |  | 
| 42 | /// @todo this should use at or should have a check | 
| 43 | inline T elementAt( size_t idx ) const | 
| 44 | { | 
| 45 | return storage[idx+m_offset]; | 
| 46 | } | 
| 47 | void removeFirst() | 
| 48 | { | 
| 49 | if (m_offset >= OFFSET_MAX_RESIZE) | 
| 50 | { | 
| 51 | storage.erase( storage.begin(), storage.begin() + m_offset + 1 ); | 
| 52 | m_offset = 0; | 
| 53 | } | 
| 54 | else | 
| 55 | ++m_offset; | 
| 56 | } | 
| 57 | inline void removeItems( size_t nb ) | 
| 58 | { | 
| 59 | assert(nb <= entries()); | 
| 60 | if (m_offset >= OFFSET_MAX_RESIZE) | 
| 61 | { | 
| 62 | storage.erase( storage.begin(), storage.begin() + m_offset + nb ); | 
| 63 | m_offset = 0; | 
| 64 | } | 
| 65 | else | 
| 66 | m_offset += nb; | 
| 67 | } | 
| 68 | inline void append(const T& t) | 
| 69 | { | 
| 70 | storage.push_back(t); | 
| 71 | } | 
| 72 | inline size_t entries() const | 
| 73 | { | 
| 74 | return storage.size() - m_offset; | 
| 75 | } | 
| 76 |  | 
| 77 | private: | 
| 78 | typename ANTLR_USE_NAMESPACE(std)vector<T> storage; | 
| 79 | size_t m_offset; | 
| 80 |  | 
| 81 | CircularQueue(const CircularQueue&); | 
| 82 | const CircularQueue& operator=(const CircularQueue&); | 
| 83 | }; | 
| 84 |  | 
| 85 | #ifdef ANTLR_CXX_SUPPORTS_NAMESPACE | 
| 86 | } | 
| 87 | #endif | 
| 88 |  | 
| 89 | #endif //INC_CircularQueue_hpp__ |