实现的一些内存辅助操作函数
其中有一个函数调用了std::copy，本来想自己实现这个copy函数的，不过为了能先用上这些内存辅助函数来实现我的容器类和算法，只好过一段时间来实现一个自己的高效的实现copy函数
1 #ifndef _STL_UNINITIALIZED_H_ 2 #define _STL_UNINITIALIZED_H_ 3 4 #include "stl_algobase.h" 5 #include "stl_iterator.h" 6 #include "type_traits.h" 7 8 //#include <algorithm> 9 10 namespace zstd 11 { 12 /***************************************************************************/ 13 template<class InputIterator, class ForwardIterator, class T> 14 ForwardIterator _uninitialized_copy(InputIterator first, InputIterator last, 15 ForwardIterator result, T*); 16 template<class InputIterator, class ForwardIterator> 17 ForwardIterator _uninitialized_copy_aux(InputIterator first, InputIterator last, 18 ForwardIterator result, _true_type); 19 template<class InputIterator, class ForwardIterator> 20 ForwardIterator _uninitialized_copy_aux(InputIterator first, InputIterator last, 21 ForwardIterator result, _false_type); 22 23 template<class InputIterator, class ForwardIterator> 24 ForwardIterator 25 inline uninitialized_copy(InputIterator first, InputIterator last, ForwardIterator result) 26 { 27 return _uninitialized_copy(first, last, result, value_type(result)); 28 } 29 template<> 30 inline char *uninitialized_copy(const char *first, const char *last, char *result) 31 { 32 memmove(result, first, last - first); 33 return result + (last - first); 34 } 35 template<> 36 inline char *uninitialized_copy(char *first, char *last, char *result) 37 { 38 memmove(result, first, last - first); 39 return result + (last - first); 40 } 41 template<> 42 inline wchar_t *uninitialized_copy(const wchar_t *first, const wchar_t *last, wchar_t *result) 43 { 44 memmove(result, first, (last - first) * sizeof(wchar_t)); 45 return result + (last - first); 46 } 47 template<> 48 inline wchar_t *uninitialized_copy(wchar_t *first, wchar_t *last, wchar_t *result) 49 { 50 memmove(result, first, (last - first) * sizeof(wchar_t)); 51 return result + (last - first); 52 } 53 template<class InputIterator, class ForwardIterator, class T> 54 inline ForwardIterator _uninitialized_copy(InputIterator first, InputIterator last, 55 ForwardIterator result, T*) 56 { 57 typedef typename _type_traits<T>::is_POD_type is_POD_type; 58 return _uninitialized_copy_aux(first, last, result, is_POD_type()); 59 } 60 template<class InputIterator, class ForwardIterator> 61 inline ForwardIterator _uninitialized_copy_aux(InputIterator first, InputIterator last, 62 ForwardIterator result, _true_type) 63 { 64 return std::copy(first, last, result);//到时候记得自己实现copy 65 } 66 template<class InputIterator, class ForwardIterator> 67 ForwardIterator _uninitialized_copy_aux(InputIterator first, InputIterator last, 68 ForwardIterator result, _false_type) 69 { 70 ForwardIterator cur = result; 71 try 72 { 73 for (; first != last; ++first, ++cur) 74 construct(&*cur, *first); 75 } 76 catch (...) 77 { 78 destroy(result, cur); 79 } 80 return cur; 81 } 82 83 /***************************************************************************/ 84 template<class ForwardIterator, class T, class T1> 85 void _uninitialized_fill(ForwardIterator first, ForwardIterator last, const T& x, T1*); 86 template<class ForwardIterator, class T> 87 void _uninitialized_fill_aux(ForwardIterator first, ForwardIterator last, 88 const T& x, _true_type); 89 template<class ForwardIterator, class T> 90 void _uninitialized_fill_aux(ForwardIterator first, ForwardIterator last, 91 const T& x, _false_type); 92 93 template<class ForwardIterator, class T> 94 void uninitialized_fill(ForwardIterator first, ForwardIterator last, const T& x) 95 { 96 _uninitialized_fill(first, last, x, value_type(first)); 97 } 98 template<class ForwardIterator, class T, class T1> 99 void _uninitialized_fill(ForwardIterator first, ForwardIterator last, const T& x, T1*) 100 { 101 typedef typename _type_traits<T1>::is_POD_type is_POD; 102 _uninitialized_fill_aux(first, last, x, is_POD()); 103 } 104 template<class ForwardIterator, class T> 105 void _uninitialized_fill_aux(ForwardIterator first, ForwardIterator last, 106 const T& x, _true_type) 107 { 108 fill(first, last, x); 109 } 110 template<class ForwardIterator, class T> 111 void _uninitialized_fill_aux(ForwardIterator first, ForwardIterator last, 112 const T& x, _false_type) 113 { 114 ForwardIterator cur = first; 115 for (; cur != last; ++cur) 116 construct(&*cur, x); 117 } 118 119 /***************************************************************************/ 120 template<class ForwardIterator, class Size, class T, class T1> 121 ForwardIterator _uninitialized_fill_n(ForwardIterator first, 122 Size n, const T& x, T1*); 123 template<class ForwardIterator, class Size, class T> 124 ForwardIterator _uninitialized_n_fill_aux(ForwardIterator first, 125 Size n, const T& x, _true_type); 126 template<class ForwardIterator, class Size, class T> 127 ForwardIterator _uninitialized_n_fill_aux(ForwardIterator first, 128 Size n, const T& x, _false_type); 129 130 template<class ForwardIterator, class Size, class T> 131 inline ForwardIterator uninitialized_fill_n(ForwardIterator first, 132 Size n, const T& x) 133 { 134 return _uninitialized_fill_n(first, n, x, value_type(first)); 135 } 136 template<class ForwardIterator, class Size, class T, class T1> 137 ForwardIterator _uninitialized_fill_n(ForwardIterator first, 138 Size n, const T& x, T1*) 139 { 140 typedef typename _type_traits<T1>::is_POD_type is_POD; 141 return _uninitialized_fill_n_aux(first, n, x, is_POD()); 142 } 143 template<class ForwardIterator, class Size, class T> 144 ForwardIterator _uninitialized_n_fill_aux(ForwardIterator first, 145 Size n, const T& x, _true_type) 146 { 147 return fill_n(first, n, x); 148 } 149 template<class ForwardIterator, class Size, class T> 150 ForwardIterator _uninitialized_n_fill_aux(ForwardIterator first, 151 Size n, const T& x, _false_type) 152 { 153 ForwardIterator cur = first; 154 for (; n > 0; --n, ++cur) 155 construct(&*cur, x); 156 return cur; 157 } 158 159 } 160 #endif
