| #ifndef SCOPED_PTR_H |
| #define SCOPED_PTR_H |
| |
| // (C) Copyright Greg Colvin and Beman Dawes 1998, 1999. |
| // Copyright (c) 2001, 2002 Peter Dimov |
| // |
| // Permission is hereby granted, free of charge, to any person or organization |
| // obtaining a copy of the software and accompanying documentation covered by |
| // this license (the "Software") to use, reproduce, display, distribute, |
| // execute, and transmit the Software, and to prepare derivative works of the |
| // Software, and to permit third-parties to whom the Software is furnished to |
| // do so, all subject to the following: |
| // |
| // The copyright notices in the Software and this entire statement, including |
| // the above license grant, this restriction and the following disclaimer, |
| // must be included in all copies of the Software, in whole or in part, and |
| // all derivative works of the Software, unless such copies or derivative |
| // works are solely in the form of machine-executable object code generated by |
| // a source language processor. |
| // |
| // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| // FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT |
| // SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE |
| // FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE, |
| // ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER |
| // DEALINGS IN THE SOFTWARE. |
| // |
| // See http://www.boost.org/libs/smart_ptr/scoped_ptr.htm for documentation. |
| // |
| // |
| // scoped_ptr mimics a built-in pointer except that it guarantees deletion |
| // of the object pointed to, either on destruction of the scoped_ptr or via |
| // an explicit reset(). scoped_ptr is a simple solution for simple needs; |
| // use shared_ptr if your needs are more complex. |
| // |
| // *** NOTE *** |
| // If your scoped_ptr is a class member of class FOO pointing to a |
| // forward declared type BAR (as shown below), then at creation (and |
| // destruction) of an object of type FOO, BAR must be complete. You can do |
| // this by either: |
| // - Making all FOO constructors and destructors non-inlined to FOO's class |
| // definition, instead placing them in foo.cc below an include of bar.h |
| // - Including bar.h before any creation or destruction of any object of |
| // type FOO |
| // The former is probably the less error-prone method, as shown below. |
| // |
| // Example: |
| // |
| // -- foo.h -- |
| // class BAR; |
| // |
| // class FOO { |
| // public: |
| // FOO(); // Required for sources that instantiate class FOO to compile! |
| // ~FOO(); // Required for sources that instantiate class FOO to compile! |
| // |
| // private: |
| // scoped_ptr<BAR> bar_; |
| // }; |
| // |
| // -- foo.cc -- |
| // #include "bar.h" |
| // #include "foo.h" |
| // FOO::FOO() {} // Empty, but must be non-inlined to FOO's class definition. |
| // FOO::~FOO() {} // Empty, but must be non-inlined to FOO's class definition. |
| // |
| // scoped_ptr_malloc added in by Ray Sidney of Google. When one of |
| // these goes out of scope, instead of doing a delete or delete[], it |
| // calls free(). scoped_ptr_malloc<char> is likely to see much more |
| // use than any other specializations. |
| // |
| // release() added in by Spencer Kimball of Google. Use this to conditionally |
| // transfer ownership of a heap-allocated object to the caller, usually on |
| // method success. |
| |
| #include <cstddef> // for std::ptrdiff_t |
| #include <assert.h> // for assert |
| #include <stdlib.h> // for free() decl |
| |
| template <typename T> |
| class scoped_ptr; |
| |
| template <typename T> |
| class scoped_ptr { |
| private: |
| |
| T* ptr; |
| |
| // scoped_ptr's must not be copied. We make sure of that by making the |
| // copy constructor prototype private. At the same time, there is no body |
| // for this constructor. Thus, if anything that has access to private |
| // members of scoped_ptr ever (inadvertently) copies a scoped_ptr, the |
| // linker will complain about missing symbols. This is a good thing! |
| scoped_ptr(scoped_ptr const &); |
| scoped_ptr & operator=(scoped_ptr const &); |
| |
| public: |
| |
| typedef T element_type; |
| |
| explicit scoped_ptr(T* p = 0): ptr(p) {} |
| |
| ~scoped_ptr() { |
| typedef char type_must_be_complete[sizeof(T)]; |
| delete ptr; |
| } |
| |
| void reset(T* p = 0) { |
| typedef char type_must_be_complete[sizeof(T)]; |
| |
| if (ptr != p) { |
| delete ptr; |
| ptr = p; |
| } |
| } |
| |
| T& operator*() const { |
| assert(ptr != 0); |
| return *ptr; |
| } |
| |
| T* operator->() const { |
| assert(ptr != 0); |
| return ptr; |
| } |
| |
| bool operator==(T* p) const { |
| return ptr == p; |
| } |
| |
| bool operator!=(T* p) const { |
| return ptr != p; |
| } |
| |
| T* get() const { |
| return ptr; |
| } |
| |
| void swap(scoped_ptr & b) { |
| T* tmp = b.ptr; |
| b.ptr = ptr; |
| ptr = tmp; |
| } |
| |
| T* release() { |
| T* tmp = ptr; |
| ptr = 0; |
| return tmp; |
| } |
| |
| private: |
| |
| // no reason to use these: each scoped_ptr should have its own object |
| template <typename U> bool operator==(scoped_ptr<U> const& p) const; |
| template <typename U> bool operator!=(scoped_ptr<U> const& p) const; |
| }; |
| |
| template<typename T> inline |
| void swap(scoped_ptr<T>& a, scoped_ptr<T>& b) { |
| a.swap(b); |
| } |
| |
| template<typename T> inline |
| bool operator==(T* p, const scoped_ptr<T>& b) { |
| return p == b.get(); |
| } |
| |
| template<typename T> inline |
| bool operator!=(T* p, const scoped_ptr<T>& b) { |
| return p != b.get(); |
| } |
| |
| // scoped_array extends scoped_ptr to arrays. Deletion of the array pointed to |
| // is guaranteed, either on destruction of the scoped_array or via an explicit |
| // reset(). Use shared_array or std::vector if your needs are more complex. |
| |
| template<typename T> |
| class scoped_array { |
| private: |
| |
| T* ptr; |
| |
| scoped_array(scoped_array const &); |
| scoped_array & operator=(scoped_array const &); |
| |
| public: |
| |
| typedef T element_type; |
| |
| explicit scoped_array(T* p = 0) : ptr(p) {} |
| |
| ~scoped_array() { |
| typedef char type_must_be_complete[sizeof(T)]; |
| delete[] ptr; |
| } |
| |
| void reset(T* p = 0) { |
| typedef char type_must_be_complete[sizeof(T)]; |
| |
| if (ptr != p) { |
| delete [] ptr; |
| ptr = p; |
| } |
| } |
| |
| T& operator[](std::ptrdiff_t i) const { |
| assert(ptr != 0); |
| assert(i >= 0); |
| return ptr[i]; |
| } |
| |
| bool operator==(T* p) const { |
| return ptr == p; |
| } |
| |
| bool operator!=(T* p) const { |
| return ptr != p; |
| } |
| |
| T* get() const { |
| return ptr; |
| } |
| |
| void swap(scoped_array & b) { |
| T* tmp = b.ptr; |
| b.ptr = ptr; |
| ptr = tmp; |
| } |
| |
| T* release() { |
| T* tmp = ptr; |
| ptr = 0; |
| return tmp; |
| } |
| |
| private: |
| |
| // no reason to use these: each scoped_array should have its own object |
| template <typename U> bool operator==(scoped_array<U> const& p) const; |
| template <typename U> bool operator!=(scoped_array<U> const& p) const; |
| }; |
| |
| template<class T> inline |
| void swap(scoped_array<T>& a, scoped_array<T>& b) { |
| a.swap(b); |
| } |
| |
| template<typename T> inline |
| bool operator==(T* p, const scoped_array<T>& b) { |
| return p == b.get(); |
| } |
| |
| template<typename T> inline |
| bool operator!=(T* p, const scoped_array<T>& b) { |
| return p != b.get(); |
| } |
| |
| |
| // This class wraps the c library function free() in a class that can be |
| // passed as a template argument to scoped_ptr_malloc below. |
| class ScopedPtrMallocFree { |
| public: |
| inline void operator()(void* x) const { |
| free(x); |
| } |
| }; |
| |
| // scoped_ptr_malloc<> is similar to scoped_ptr<>, but it accepts a |
| // second template argument, the functor used to free the object. |
| |
| template<typename T, typename FreeProc = ScopedPtrMallocFree> |
| class scoped_ptr_malloc { |
| private: |
| |
| T* ptr; |
| |
| scoped_ptr_malloc(scoped_ptr_malloc const &); |
| scoped_ptr_malloc & operator=(scoped_ptr_malloc const &); |
| |
| public: |
| |
| typedef T element_type; |
| |
| explicit scoped_ptr_malloc(T* p = 0): ptr(p) {} |
| |
| ~scoped_ptr_malloc() { |
| typedef char type_must_be_complete[sizeof(T)]; |
| free_((void*) ptr); |
| } |
| |
| void reset(T* p = 0) { |
| typedef char type_must_be_complete[sizeof(T)]; |
| |
| if (ptr != p) { |
| free_((void*) ptr); |
| ptr = p; |
| } |
| } |
| |
| T& operator*() const { |
| assert(ptr != 0); |
| return *ptr; |
| } |
| |
| T* operator->() const { |
| assert(ptr != 0); |
| return ptr; |
| } |
| |
| bool operator==(T* p) const { |
| return ptr == p; |
| } |
| |
| bool operator!=(T* p) const { |
| return ptr != p; |
| } |
| |
| T* get() const { |
| return ptr; |
| } |
| |
| void swap(scoped_ptr_malloc & b) { |
| T* tmp = b.ptr; |
| b.ptr = ptr; |
| ptr = tmp; |
| } |
| |
| T* release() { |
| T* tmp = ptr; |
| ptr = 0; |
| return tmp; |
| } |
| |
| private: |
| |
| // no reason to use these: each scoped_ptr_malloc should have its own object |
| template <typename U, typename GP> |
| bool operator==(scoped_ptr_malloc<U, GP> const& p) const; |
| template <typename U, typename GP> |
| bool operator!=(scoped_ptr_malloc<U, GP> const& p) const; |
| |
| static FreeProc const free_; |
| }; |
| |
| template<typename T, typename FP> |
| FP const scoped_ptr_malloc<T,FP>::free_ = FP(); |
| |
| template<typename T, typename FP> inline |
| void swap(scoped_ptr_malloc<T,FP>& a, scoped_ptr_malloc<T,FP>& b) { |
| a.swap(b); |
| } |
| |
| template<typename T, typename FP> inline |
| bool operator==(T* p, const scoped_ptr_malloc<T,FP>& b) { |
| return p == b.get(); |
| } |
| |
| template<typename T, typename FP> inline |
| bool operator!=(T* p, const scoped_ptr_malloc<T,FP>& b) { |
| return p != b.get(); |
| } |
| |
| #endif // #ifndef SCOPED_PTR_H |