michael@0: //  (C) Copyright Greg Colvin and Beman Dawes 1998, 1999.
michael@0: //  Copyright (c) 2001, 2002 Peter Dimov
michael@0: //
michael@0: //  Permission to copy, use, modify, sell and distribute this software
michael@0: //  is granted provided this copyright notice appears in all copies.
michael@0: //  This software is provided "as is" without express or implied
michael@0: //  warranty, and with no claim as to its suitability for any purpose.
michael@0: //
michael@0: //  See http://www.boost.org/libs/smart_ptr/scoped_ptr.htm for documentation.
michael@0: //
michael@0: 
michael@0: //  scoped_ptr mimics a built-in pointer except that it guarantees deletion
michael@0: //  of the object pointed to, either on destruction of the scoped_ptr or via
michael@0: //  an explicit reset(). scoped_ptr is a simple solution for simple needs;
michael@0: //  use shared_ptr or std::auto_ptr if your needs are more complex.
michael@0: 
michael@0: //  *** NOTE ***
michael@0: //  If your scoped_ptr is a class member of class FOO pointing to a 
michael@0: //  forward declared type BAR (as shown below), then you MUST use a non-inlined 
michael@0: //  version of the destructor.  The destructor of a scoped_ptr (called from
michael@0: //  FOO's destructor) must have a complete definition of BAR in order to 
michael@0: //  destroy it.  Example:
michael@0: //
michael@0: //  -- foo.h --
michael@0: //  class BAR;
michael@0: //
michael@0: //  class FOO {
michael@0: //   public:
michael@0: //    FOO();
michael@0: //    ~FOO();  // Required for sources that instantiate class FOO to compile!
michael@0: //    
michael@0: //   private:
michael@0: //    scoped_ptr<BAR> bar_;
michael@0: //  };
michael@0: //
michael@0: //  -- foo.cc --
michael@0: //  #include "foo.h"
michael@0: //  FOO::~FOO() {} // Empty, but must be non-inlined to FOO's class definition.
michael@0: 
michael@0: //  scoped_ptr_malloc added by Google
michael@0: //  When one of these goes out of scope, instead of doing a delete or
michael@0: //  delete[], it calls free().  scoped_ptr_malloc<char> is likely to see
michael@0: //  much more use than any other specializations.
michael@0: 
michael@0: //  release() added by Google
michael@0: //  Use this to conditionally transfer ownership of a heap-allocated object
michael@0: //  to the caller, usually on method success.
michael@0: 
michael@0: #ifndef COMMON_SCOPED_PTR_H_
michael@0: #define COMMON_SCOPED_PTR_H_
michael@0: 
michael@0: #include <cstddef>            // for std::ptrdiff_t
michael@0: #include <assert.h>           // for assert
michael@0: #include <stdlib.h>           // for free() decl
michael@0: 
michael@0: namespace google_breakpad {
michael@0: 
michael@0: template <typename T>
michael@0: class scoped_ptr {
michael@0:  private:
michael@0: 
michael@0:   T* ptr;
michael@0: 
michael@0:   scoped_ptr(scoped_ptr const &);
michael@0:   scoped_ptr & operator=(scoped_ptr const &);
michael@0: 
michael@0:  public:
michael@0: 
michael@0:   typedef T element_type;
michael@0: 
michael@0:   explicit scoped_ptr(T* p = 0): ptr(p) {}
michael@0: 
michael@0:   ~scoped_ptr() {
michael@0:     typedef char type_must_be_complete[sizeof(T)];
michael@0:     delete ptr;
michael@0:   }
michael@0: 
michael@0:   void reset(T* p = 0) {
michael@0:     typedef char type_must_be_complete[sizeof(T)];
michael@0: 
michael@0:     if (ptr != p) {
michael@0:       delete ptr;
michael@0:       ptr = p;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   T& operator*() const {
michael@0:     assert(ptr != 0);
michael@0:     return *ptr;
michael@0:   }
michael@0: 
michael@0:   T* operator->() const  {
michael@0:     assert(ptr != 0);
michael@0:     return ptr;
michael@0:   }
michael@0: 
michael@0:   bool operator==(T* p) const {
michael@0:     return ptr == p;
michael@0:   }
michael@0: 
michael@0:   bool operator!=(T* p) const {
michael@0:     return ptr != p;
michael@0:   }
michael@0: 
michael@0:   T* get() const  {
michael@0:     return ptr;
michael@0:   }
michael@0: 
michael@0:   void swap(scoped_ptr & b) {
michael@0:     T* tmp = b.ptr;
michael@0:     b.ptr = ptr;
michael@0:     ptr = tmp;
michael@0:   }
michael@0: 
michael@0:   T* release() {
michael@0:     T* tmp = ptr;
michael@0:     ptr = 0;
michael@0:     return tmp;
michael@0:   }
michael@0: 
michael@0:  private:
michael@0: 
michael@0:   // no reason to use these: each scoped_ptr should have its own object
michael@0:   template <typename U> bool operator==(scoped_ptr<U> const& p) const;
michael@0:   template <typename U> bool operator!=(scoped_ptr<U> const& p) const;
michael@0: };
michael@0: 
michael@0: template<typename T> inline
michael@0: void swap(scoped_ptr<T>& a, scoped_ptr<T>& b) {
michael@0:   a.swap(b);
michael@0: }
michael@0: 
michael@0: template<typename T> inline
michael@0: bool operator==(T* p, const scoped_ptr<T>& b) {
michael@0:   return p == b.get();
michael@0: }
michael@0: 
michael@0: template<typename T> inline
michael@0: bool operator!=(T* p, const scoped_ptr<T>& b) {
michael@0:   return p != b.get();
michael@0: }
michael@0: 
michael@0: //  scoped_array extends scoped_ptr to arrays. Deletion of the array pointed to
michael@0: //  is guaranteed, either on destruction of the scoped_array or via an explicit
michael@0: //  reset(). Use shared_array or std::vector if your needs are more complex.
michael@0: 
michael@0: template<typename T>
michael@0: class scoped_array {
michael@0:  private:
michael@0: 
michael@0:   T* ptr;
michael@0: 
michael@0:   scoped_array(scoped_array const &);
michael@0:   scoped_array & operator=(scoped_array const &);
michael@0: 
michael@0:  public:
michael@0: 
michael@0:   typedef T element_type;
michael@0: 
michael@0:   explicit scoped_array(T* p = 0) : ptr(p) {}
michael@0: 
michael@0:   ~scoped_array() {
michael@0:     typedef char type_must_be_complete[sizeof(T)];
michael@0:     delete[] ptr;
michael@0:   }
michael@0: 
michael@0:   void reset(T* p = 0) {
michael@0:     typedef char type_must_be_complete[sizeof(T)];
michael@0: 
michael@0:     if (ptr != p) {
michael@0:       delete [] ptr;
michael@0:       ptr = p;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   T& operator[](std::ptrdiff_t i) const {
michael@0:     assert(ptr != 0);
michael@0:     assert(i >= 0);
michael@0:     return ptr[i];
michael@0:   }
michael@0: 
michael@0:   bool operator==(T* p) const {
michael@0:     return ptr == p;
michael@0:   }
michael@0: 
michael@0:   bool operator!=(T* p) const {
michael@0:     return ptr != p;
michael@0:   }
michael@0: 
michael@0:   T* get() const {
michael@0:     return ptr;
michael@0:   }
michael@0: 
michael@0:   void swap(scoped_array & b) {
michael@0:     T* tmp = b.ptr;
michael@0:     b.ptr = ptr;
michael@0:     ptr = tmp;
michael@0:   }
michael@0: 
michael@0:   T* release() {
michael@0:     T* tmp = ptr;
michael@0:     ptr = 0;
michael@0:     return tmp;
michael@0:   }
michael@0: 
michael@0:  private:
michael@0: 
michael@0:   // no reason to use these: each scoped_array should have its own object
michael@0:   template <typename U> bool operator==(scoped_array<U> const& p) const;
michael@0:   template <typename U> bool operator!=(scoped_array<U> const& p) const;
michael@0: };
michael@0: 
michael@0: template<class T> inline
michael@0: void swap(scoped_array<T>& a, scoped_array<T>& b) {
michael@0:   a.swap(b);
michael@0: }
michael@0: 
michael@0: template<typename T> inline
michael@0: bool operator==(T* p, const scoped_array<T>& b) {
michael@0:   return p == b.get();
michael@0: }
michael@0: 
michael@0: template<typename T> inline
michael@0: bool operator!=(T* p, const scoped_array<T>& b) {
michael@0:   return p != b.get();
michael@0: }
michael@0: 
michael@0: 
michael@0: // This class wraps the c library function free() in a class that can be
michael@0: // passed as a template argument to scoped_ptr_malloc below.
michael@0: class ScopedPtrMallocFree {
michael@0:  public:
michael@0:   inline void operator()(void* x) const {
michael@0:     free(x);
michael@0:   }
michael@0: };
michael@0: 
michael@0: // scoped_ptr_malloc<> is similar to scoped_ptr<>, but it accepts a
michael@0: // second template argument, the functor used to free the object.
michael@0: 
michael@0: template<typename T, typename FreeProc = ScopedPtrMallocFree>
michael@0: class scoped_ptr_malloc {
michael@0:  private:
michael@0: 
michael@0:   T* ptr;
michael@0: 
michael@0:   scoped_ptr_malloc(scoped_ptr_malloc const &);
michael@0:   scoped_ptr_malloc & operator=(scoped_ptr_malloc const &);
michael@0: 
michael@0:  public:
michael@0: 
michael@0:   typedef T element_type;
michael@0: 
michael@0:   explicit scoped_ptr_malloc(T* p = 0): ptr(p) {}
michael@0: 
michael@0:   ~scoped_ptr_malloc() {
michael@0:     typedef char type_must_be_complete[sizeof(T)];
michael@0:     free_((void*) ptr);
michael@0:   }
michael@0: 
michael@0:   void reset(T* p = 0) {
michael@0:     typedef char type_must_be_complete[sizeof(T)];
michael@0: 
michael@0:     if (ptr != p) {
michael@0:       free_((void*) ptr);
michael@0:       ptr = p;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   T& operator*() const {
michael@0:     assert(ptr != 0);
michael@0:     return *ptr;
michael@0:   }
michael@0: 
michael@0:   T* operator->() const {
michael@0:     assert(ptr != 0);
michael@0:     return ptr;
michael@0:   }
michael@0: 
michael@0:   bool operator==(T* p) const {
michael@0:     return ptr == p;
michael@0:   }
michael@0: 
michael@0:   bool operator!=(T* p) const {
michael@0:     return ptr != p;
michael@0:   }
michael@0: 
michael@0:   T* get() const {
michael@0:     return ptr;
michael@0:   }
michael@0: 
michael@0:   void swap(scoped_ptr_malloc & b) {
michael@0:     T* tmp = b.ptr;
michael@0:     b.ptr = ptr;
michael@0:     ptr = tmp;
michael@0:   }
michael@0: 
michael@0:   T* release() {
michael@0:     T* tmp = ptr;
michael@0:     ptr = 0;
michael@0:     return tmp;
michael@0:   }
michael@0: 
michael@0:  private:
michael@0: 
michael@0:   // no reason to use these: each scoped_ptr_malloc should have its own object
michael@0:   template <typename U, typename GP>
michael@0:   bool operator==(scoped_ptr_malloc<U, GP> const& p) const;
michael@0:   template <typename U, typename GP>
michael@0:   bool operator!=(scoped_ptr_malloc<U, GP> const& p) const;
michael@0: 
michael@0:   static FreeProc const free_;
michael@0: };
michael@0: 
michael@0: template<typename T, typename FP>
michael@0: FP const scoped_ptr_malloc<T,FP>::free_ = FP();
michael@0: 
michael@0: template<typename T, typename FP> inline
michael@0: void swap(scoped_ptr_malloc<T,FP>& a, scoped_ptr_malloc<T,FP>& b) {
michael@0:   a.swap(b);
michael@0: }
michael@0: 
michael@0: template<typename T, typename FP> inline
michael@0: bool operator==(T* p, const scoped_ptr_malloc<T,FP>& b) {
michael@0:   return p == b.get();
michael@0: }
michael@0: 
michael@0: template<typename T, typename FP> inline
michael@0: bool operator!=(T* p, const scoped_ptr_malloc<T,FP>& b) {
michael@0:   return p != b.get();
michael@0: }
michael@0: 
michael@0: }  // namespace google_breakpad
michael@0: 
michael@0: #endif  // COMMON_SCOPED_PTR_H_