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 //  (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 COMMON_SCOPED_PTR_H_

 #define COMMON_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  // COMMON_SCOPED_PTR_H_