1 | #ifndef INC_RefCount_hpp__ |
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2 | #define INC_RefCount_hpp__ |
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3 | /* ANTLR Translator Generator |
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4 | * Project led by Terence Parr at http://www.jGuru.com |
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5 | * Software rights: http://www.antlr.org/license.html |
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6 | * |
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7 | * $Id: //depot/code/org.antlr/release/antlr-2.7.7/lib/cpp/antlr/RefCount.hpp#2 $ |
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8 | */ |
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9 | |
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10 | #include <antlr/config.hpp> |
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11 | |
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12 | #ifdef ANTLR_CXX_SUPPORTS_NAMESPACE |
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13 | namespace antlr { |
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14 | #endif |
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15 | |
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16 | template<class T> |
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17 | class ANTLR_API RefCount { |
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18 | private: |
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19 | struct Ref { |
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20 | T* const ptr; |
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21 | unsigned int count; |
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22 | |
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23 | Ref(T* p) : ptr(p), count(1) {} |
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24 | ~Ref() {delete ptr;} |
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25 | Ref* increment() {++count;return this;} |
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26 | bool decrement() {return (--count==0);} |
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27 | private: |
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28 | Ref(const Ref&); |
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29 | Ref& operator=(const Ref&); |
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30 | }* ref; |
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31 | |
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32 | public: |
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33 | explicit RefCount(T* p = 0) |
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34 | : ref(p ? new Ref(p) : 0) |
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35 | { |
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36 | } |
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37 | RefCount(const RefCount<T>& other) |
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38 | : ref(other.ref ? other.ref->increment() : 0) |
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39 | { |
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40 | } |
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41 | ~RefCount() |
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42 | { |
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43 | if (ref && ref->decrement()) |
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44 | delete ref; |
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45 | } |
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46 | RefCount<T>& operator=(const RefCount<T>& other) |
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47 | { |
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48 | Ref* tmp = other.ref ? other.ref->increment() : 0; |
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49 | if (ref && ref->decrement()) |
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50 | delete ref; |
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51 | ref = tmp; |
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52 | return *this; |
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53 | } |
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54 | |
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55 | operator T* () const |
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56 | { |
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57 | return ref ? ref->ptr : 0; |
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58 | } |
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59 | |
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60 | T* operator->() const |
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61 | { |
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62 | return ref ? ref->ptr : 0; |
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63 | } |
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64 | |
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65 | T* get() const |
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66 | { |
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67 | return ref ? ref->ptr : 0; |
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68 | } |
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69 | |
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70 | template<class newType> operator RefCount<newType>() |
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71 | { |
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72 | return RefCount<newType>(ref); |
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73 | } |
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74 | }; |
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75 | |
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76 | #ifdef ANTLR_CXX_SUPPORTS_NAMESPACE |
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77 | } |
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78 | #endif |
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79 | |
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80 | #endif //INC_RefCount_hpp__ |
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