// (C) Copyright Greg Colvin and Beman Dawes 1998, 1999. // Copyright (c) 2001, 2002 Peter Dimov // // Permission to copy, use, modify, sell and distribute this software // is granted provided this copyright notice appears in all copies. // This software is provided "as is" without express or implied // warranty, and with no claim as to its suitability for any purpose. // // 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 or std::auto_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 you MUST use a non-inlined // version of the destructor. The destructor of a scoped_ptr (called from // FOO's destructor) must have a complete definition of BAR in order to // destroy it. Example: // // -- foo.h -- // class BAR; // // class FOO { // public: // FOO(); // ~FOO(); // Required for sources that instantiate class FOO to compile! // // private: // scoped_ptr<BAR> bar_; // }; // // -- foo.cc -- // #include "foo.h" // FOO::~FOO() {} // Empty, but must be non-inlined to FOO's class definition. // scoped_ptr_malloc added by 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 by Google // Use this to conditionally transfer ownership of a heap-allocated object // to the caller, usually on method success. #ifndef PROCESSOR_SCOPED_PTR_H__ #define PROCESSOR_SCOPED_PTR_H__ #include <cstddef> // for std::ptrdiff_t #include <assert.h> // for assert #include <stdlib.h> // for free() decl namespace google_breakpad { template <typename T> class scoped_ptr { private: T* ptr; 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(); } } // namespace google_breakpad #endif // PROCESSOR_SCOPED_PTR_H__