| 1 | #ifndef INC_ASTRefCount_hpp__ | 
| 2 | # define INC_ASTRefCount_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 | * $Id$ | 
| 9 | */ | 
| 10 |  | 
| 11 | # include <antlr/config.hpp> | 
| 12 |  | 
| 13 | #ifdef ANTLR_CXX_SUPPORTS_NAMESPACE | 
| 14 | namespace antlr { | 
| 15 | #endif | 
| 16 |  | 
| 17 | class AST; | 
| 18 |  | 
| 19 | struct ANTLR_API ASTRef | 
| 20 | { | 
| 21 | AST* const ptr; | 
| 22 | unsigned int count; | 
| 23 |  | 
| 24 | ASTRef(AST* p); | 
| 25 | ~ASTRef(); | 
| 26 | ASTRef* increment() | 
| 27 | { | 
| 28 | ++count; | 
| 29 | return this; | 
| 30 | } | 
| 31 | bool decrement() | 
| 32 | { | 
| 33 | return (--count==0); | 
| 34 | } | 
| 35 |  | 
| 36 | static ASTRef* getRef(const AST* p); | 
| 37 | private: | 
| 38 | ASTRef( const ASTRef& ); | 
| 39 | ASTRef& operator=( const ASTRef& ); | 
| 40 | }; | 
| 41 |  | 
| 42 | template<class T> | 
| 43 | class ANTLR_API ASTRefCount | 
| 44 | { | 
| 45 | private: | 
| 46 | ASTRef* ref; | 
| 47 |  | 
| 48 | public: | 
| 49 | ASTRefCount(const AST* p=0) | 
| 50 | : ref(p ? ASTRef::getRef(p) : 0) | 
| 51 | { | 
| 52 | } | 
| 53 | ASTRefCount(const ASTRefCount<T>& other) | 
| 54 | : ref(other.ref ? other.ref->increment() : 0) | 
| 55 | { | 
| 56 | } | 
| 57 | ~ASTRefCount() | 
| 58 | { | 
| 59 | if (ref && ref->decrement()) | 
| 60 | delete ref; | 
| 61 | } | 
| 62 | ASTRefCount<T>& operator=(AST* other) | 
| 63 | { | 
| 64 | ASTRef* tmp = ASTRef::getRef(other); | 
| 65 |  | 
| 66 | if (ref && ref->decrement()) | 
| 67 | delete ref; | 
| 68 |  | 
| 69 | ref=tmp; | 
| 70 |  | 
| 71 | return *this; | 
| 72 | } | 
| 73 | ASTRefCount<T>& operator=(const ASTRefCount<T>& other) | 
| 74 | { | 
| 75 | if( other.ref != ref ) | 
| 76 | { | 
| 77 | ASTRef* tmp = other.ref ? other.ref->increment() : 0; | 
| 78 |  | 
| 79 | if (ref && ref->decrement()) | 
| 80 | delete ref; | 
| 81 |  | 
| 82 | ref=tmp; | 
| 83 | } | 
| 84 | return *this; | 
| 85 | } | 
| 86 |  | 
| 87 | operator T* ()  const { return ref ? static_cast<T*>(ref->ptr) : 0; } | 
| 88 | T* operator->() const { return ref ? static_cast<T*>(ref->ptr) : 0; } | 
| 89 | T* get()        const { return ref ? static_cast<T*>(ref->ptr) : 0; } | 
| 90 | }; | 
| 91 |  | 
| 92 | typedef ASTRefCount<AST> RefAST; | 
| 93 |  | 
| 94 | #ifdef ANTLR_CXX_SUPPORTS_NAMESPACE | 
| 95 | } | 
| 96 | #endif | 
| 97 |  | 
| 98 | #endif //INC_ASTRefCount_hpp__ |