src/common/scoped_ptr.h - breakpad - Git at Google

 // Copyright 2013 Google Inc. All Rights Reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 // copyright notice, this list of conditions and the following disclaimer
 // in the documentation and/or other materials provided with the
 // distribution.
 //     * Neither the name of Google Inc. nor the names of its
 // contributors may be used to endorse or promote products derived from
 // this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 // Scopers help you manage ownership of a pointer, helping you easily manage the
 // a pointer within a scope, and automatically destroying the pointer at the
 // end of a scope.  There are two main classes you will use, which correspond
 // to the operators new/delete and new[]/delete[].
 //
 // Example usage (scoped_ptr):
 //   {
 //     scoped_ptr<Foo> foo(new Foo("wee"));
 //   }  // foo goes out of scope, releasing the pointer with it.
 //
 //   {
 //     scoped_ptr<Foo> foo;          // No pointer managed.
 //     foo.reset(new Foo("wee"));    // Now a pointer is managed.
 //     foo.reset(new Foo("wee2"));   // Foo("wee") was destroyed.
 //     foo.reset(new Foo("wee3"));   // Foo("wee2") was destroyed.
 //     foo->Method();                // Foo::Method() called.
 //     foo.get()->Method();          // Foo::Method() called.
 //     SomeFunc(foo.release());      // SomeFunc takes ownership, foo no longer
 //                                   // manages a pointer.
 //     foo.reset(new Foo("wee4"));   // foo manages a pointer again.
 //     foo.reset();                  // Foo("wee4") destroyed, foo no longer
 //                                   // manages a pointer.
 //   }  // foo wasn't managing a pointer, so nothing was destroyed.
 //
 // Example usage (scoped_array):
 //   {
 //     scoped_array<Foo> foo(new Foo[100]);
 //     foo.get()->Method();  // Foo::Method on the 0th element.
 //     foo[10].Method();     // Foo::Method on the 10th element.
 //   }

 #ifndef COMMON_SCOPED_PTR_H_
 #define COMMON_SCOPED_PTR_H_

 // This is an implementation designed to match the anticipated future TR2
 // implementation of the scoped_ptr class, and its closely-related brethren,
 // scoped_array, scoped_ptr_malloc.

 #include <assert.h>
 #include <stddef.h>
 #include <stdlib.h>

 namespace google_breakpad {

 // A scoped_ptr<T> is like a T*, except that the destructor of scoped_ptr<T>
 // automatically deletes the pointer it holds (if any).
 // That is, scoped_ptr<T> owns the T object that it points to.
 // Like a T*, a scoped_ptr<T> may hold either NULL or a pointer to a T object.
 // Also like T*, scoped_ptr<T> is thread-compatible, and once you
 // dereference it, you get the threadsafety guarantees of T.
 //
 // The size of a scoped_ptr is small:
 // sizeof(scoped_ptr<C>) == sizeof(C*)
 template <class C>
 class scoped_ptr {
  public:

   // The element type
   typedef C element_type;

   // Constructor.  Defaults to initializing with NULL.
   // There is no way to create an uninitialized scoped_ptr.
   // The input parameter must be allocated with new.
   explicit scoped_ptr(C* p = NULL) : ptr_(p) { }

   // Destructor.  If there is a C object, delete it.
   // We don't need to test ptr_ == NULL because C++ does that for us.
   ~scoped_ptr() {
     enum { type_must_be_complete = sizeof(C) };
     delete ptr_;
   }

   // Reset.  Deletes the current owned object, if any.
   // Then takes ownership of a new object, if given.
   // this->reset(this->get()) works.
   void reset(C* p = NULL) {
     if (p != ptr_) {
       enum { type_must_be_complete = sizeof(C) };
       delete ptr_;
       ptr_ = p;
     }
   }

   // Accessors to get the owned object.
   // operator* and operator-> will assert() if there is no current object.
   C& operator*() const {
     assert(ptr_ != NULL);
     return *ptr_;
   }
   C* operator->() const  {
     assert(ptr_ != NULL);
     return ptr_;
   }
   C* get() const { return ptr_; }

   // Comparison operators.
   // These return whether two scoped_ptr refer to the same object, not just to
   // two different but equal objects.
   bool operator==(C* p) const { return ptr_ == p; }
   bool operator!=(C* p) const { return ptr_ != p; }

   // Swap two scoped pointers.
   void swap(scoped_ptr& p2) {
     C* tmp = ptr_;
     ptr_ = p2.ptr_;
     p2.ptr_ = tmp;
   }

   // Release a pointer.
   // The return value is the current pointer held by this object.
   // If this object holds a NULL pointer, the return value is NULL.
   // After this operation, this object will hold a NULL pointer,
   // and will not own the object any more.
   C* release() {
     C* retVal = ptr_;
     ptr_ = NULL;
     return retVal;
   }

  private:
   C* ptr_;

   // Forbid comparison of scoped_ptr types.  If C2 != C, it totally doesn't
   // make sense, and if C2 == C, it still doesn't make sense because you should
   // never have the same object owned by two different scoped_ptrs.
   template <class C2> bool operator==(scoped_ptr<C2> const& p2) const;
   template <class C2> bool operator!=(scoped_ptr<C2> const& p2) const;

   // Disallow evil constructors
   scoped_ptr(const scoped_ptr&);
   void operator=(const scoped_ptr&);
 };

 // Free functions
 template <class C>
 void swap(scoped_ptr<C>& p1, scoped_ptr<C>& p2) {
   p1.swap(p2);
 }

 template <class C>
 bool operator==(C* p1, const scoped_ptr<C>& p2) {
   return p1 == p2.get();
 }

 template <class C>
 bool operator!=(C* p1, const scoped_ptr<C>& p2) {
   return p1 != p2.get();
 }

 // scoped_array<C> is like scoped_ptr<C>, except that the caller must allocate
 // with new [] and the destructor deletes objects with delete [].
 //
 // As with scoped_ptr<C>, a scoped_array<C> either points to an object
 // or is NULL.  A scoped_array<C> owns the object that it points to.
 // scoped_array<T> is thread-compatible, and once you index into it,
 // the returned objects have only the threadsafety guarantees of T.
 //
 // Size: sizeof(scoped_array<C>) == sizeof(C*)
 template <class C>
 class scoped_array {
  public:

   // The element type
   typedef C element_type;

   // Constructor.  Defaults to intializing with NULL.
   // There is no way to create an uninitialized scoped_array.
   // The input parameter must be allocated with new [].
   explicit scoped_array(C* p = NULL) : array_(p) { }

   // Destructor.  If there is a C object, delete it.
   // We don't need to test ptr_ == NULL because C++ does that for us.
   ~scoped_array() {
     enum { type_must_be_complete = sizeof(C) };
     delete[] array_;
   }

   // Reset.  Deletes the current owned object, if any.
   // Then takes ownership of a new object, if given.
   // this->reset(this->get()) works.
   void reset(C* p = NULL) {
     if (p != array_) {
       enum { type_must_be_complete = sizeof(C) };
       delete[] array_;
       array_ = p;
     }
   }

   // Get one element of the current object.
   // Will assert() if there is no current object, or index i is negative.
   C& operator[](ptrdiff_t i) const {
     assert(i >= 0);
     assert(array_ != NULL);
     return array_[i];
   }

   // Get a pointer to the zeroth element of the current object.
   // If there is no current object, return NULL.
   C* get() const {
     return array_;
   }

   // Comparison operators.
   // These return whether two scoped_array refer to the same object, not just to
   // two different but equal objects.
   bool operator==(C* p) const { return array_ == p; }
   bool operator!=(C* p) const { return array_ != p; }

   // Swap two scoped arrays.
   void swap(scoped_array& p2) {
     C* tmp = array_;
     array_ = p2.array_;
     p2.array_ = tmp;
   }

   // Release an array.
   // The return value is the current pointer held by this object.
   // If this object holds a NULL pointer, the return value is NULL.
   // After this operation, this object will hold a NULL pointer,
   // and will not own the object any more.
   C* release() {
     C* retVal = array_;
     array_ = NULL;
     return retVal;
   }

  private:
   C* array_;

   // Forbid comparison of different scoped_array types.
   template <class C2> bool operator==(scoped_array<C2> const& p2) const;
   template <class C2> bool operator!=(scoped_array<C2> const& p2) const;

   // Disallow evil constructors
   scoped_array(const scoped_array&);
   void operator=(const scoped_array&);
 };

 // Free functions
 template <class C>
 void swap(scoped_array<C>& p1, scoped_array<C>& p2) {
   p1.swap(p2);
 }

 template <class C>
 bool operator==(C* p1, const scoped_array<C>& p2) {
   return p1 == p2.get();
 }

 template <class C>
 bool operator!=(C* p1, const scoped_array<C>& p2) {
   return p1 != p2.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<class C, class FreeProc = ScopedPtrMallocFree>
 class scoped_ptr_malloc {
  public:

   // The element type
   typedef C element_type;

   // Constructor.  Defaults to initializing with NULL.
   // There is no way to create an uninitialized scoped_ptr.
   // The input parameter must be allocated with an allocator that matches the
   // Free functor.  For the default Free functor, this is malloc, calloc, or
   // realloc.
   explicit scoped_ptr_malloc(C* p = NULL): ptr_(p) {}

   // Destructor.  If there is a C object, call the Free functor.
   ~scoped_ptr_malloc() {
     reset();
   }

   // Reset.  Calls the Free functor on the current owned object, if any.
   // Then takes ownership of a new object, if given.
   // this->reset(this->get()) works.
   void reset(C* p = NULL) {
     if (ptr_ != p) {
       FreeProc free_proc;
       free_proc(ptr_);
       ptr_ = p;
     }
   }

   // Get the current object.
   // operator* and operator-> will cause an assert() failure if there is
   // no current object.
   C& operator*() const {
     assert(ptr_ != NULL);
     return *ptr_;
   }

   C* operator->() const {
     assert(ptr_ != NULL);
     return ptr_;
   }

   C* get() const {
     return ptr_;
   }

   // Comparison operators.
   // These return whether a scoped_ptr_malloc and a plain pointer refer
   // to the same object, not just to two different but equal objects.
   // For compatibility with the boost-derived implementation, these
   // take non-const arguments.
   bool operator==(C* p) const {
     return ptr_ == p;
   }

   bool operator!=(C* p) const {
     return ptr_ != p;
   }

   // Swap two scoped pointers.
   void swap(scoped_ptr_malloc & b) {
     C* tmp = b.ptr_;
     b.ptr_ = ptr_;
     ptr_ = tmp;
   }

   // Release a pointer.
   // The return value is the current pointer held by this object.
   // If this object holds a NULL pointer, the return value is NULL.
   // After this operation, this object will hold a NULL pointer,
   // and will not own the object any more.
   C* release() {
     C* tmp = ptr_;
     ptr_ = NULL;
     return tmp;
   }

  private:
   C* ptr_;

   // no reason to use these: each scoped_ptr_malloc should have its own object
   template <class C2, class GP>
   bool operator==(scoped_ptr_malloc<C2, GP> const& p) const;
   template <class C2, class GP>
   bool operator!=(scoped_ptr_malloc<C2, GP> const& p) const;

   // Disallow evil constructors
   scoped_ptr_malloc(const scoped_ptr_malloc&);
   void operator=(const scoped_ptr_malloc&);
 };

 template<class C, class FP> inline
 void swap(scoped_ptr_malloc<C, FP>& a, scoped_ptr_malloc<C, FP>& b) {
   a.swap(b);
 }

 template<class C, class FP> inline
 bool operator==(C* p, const scoped_ptr_malloc<C, FP>& b) {
   return p == b.get();
 }

 template<class C, class FP> inline
 bool operator!=(C* p, const scoped_ptr_malloc<C, FP>& b) {
   return p != b.get();
 }

 }  // namespace google_breakpad

 #endif  // COMMON_SCOPED_PTR_H_
	// Copyright 2013 Google Inc. All Rights Reserved.
	//
	// Redistribution and use in source and binary forms, with or without
	// modification, are permitted provided that the following conditions are
	// met:
	//
	// * Redistributions of source code must retain the above copyright
	// notice, this list of conditions and the following disclaimer.
	// * Redistributions in binary form must reproduce the above
	// copyright notice, this list of conditions and the following disclaimer
	// in the documentation and/or other materials provided with the
	// distribution.
	// * Neither the name of Google Inc. nor the names of its
	// contributors may be used to endorse or promote products derived from
	// this software without specific prior written permission.
	//
	// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

	// Scopers help you manage ownership of a pointer, helping you easily manage the
	// a pointer within a scope, and automatically destroying the pointer at the
	// end of a scope. There are two main classes you will use, which correspond
	// to the operators new/delete and new[]/delete[].
	//
	// Example usage (scoped_ptr):
	// {
	// scoped_ptr<Foo> foo(new Foo("wee"));
	// } // foo goes out of scope, releasing the pointer with it.
	//
	// {
	// scoped_ptr<Foo> foo; // No pointer managed.
	// foo.reset(new Foo("wee")); // Now a pointer is managed.
	// foo.reset(new Foo("wee2")); // Foo("wee") was destroyed.
	// foo.reset(new Foo("wee3")); // Foo("wee2") was destroyed.
	// foo->Method(); // Foo::Method() called.
	// foo.get()->Method(); // Foo::Method() called.
	// SomeFunc(foo.release()); // SomeFunc takes ownership, foo no longer
	// // manages a pointer.
	// foo.reset(new Foo("wee4")); // foo manages a pointer again.
	// foo.reset(); // Foo("wee4") destroyed, foo no longer
	// // manages a pointer.
	// } // foo wasn't managing a pointer, so nothing was destroyed.
	//
	// Example usage (scoped_array):
	// {
	// scoped_array<Foo> foo(new Foo[100]);
	// foo.get()->Method(); // Foo::Method on the 0th element.
	// foo[10].Method(); // Foo::Method on the 10th element.
	// }

	#ifndef COMMON_SCOPED_PTR_H_
	#define COMMON_SCOPED_PTR_H_

	// This is an implementation designed to match the anticipated future TR2
	// implementation of the scoped_ptr class, and its closely-related brethren,
	// scoped_array, scoped_ptr_malloc.

	#include <assert.h>
	#include <stddef.h>
	#include <stdlib.h>

	namespace google_breakpad {

	// A scoped_ptr<T> is like a T*, except that the destructor of scoped_ptr<T>
	// automatically deletes the pointer it holds (if any).
	// That is, scoped_ptr<T> owns the T object that it points to.
	// Like a T*, a scoped_ptr<T> may hold either NULL or a pointer to a T object.
	// Also like T*, scoped_ptr<T> is thread-compatible, and once you
	// dereference it, you get the threadsafety guarantees of T.
	//
	// The size of a scoped_ptr is small:
	// sizeof(scoped_ptr<C>) == sizeof(C*)
	template <class C>
	class scoped_ptr {
	public:

	// The element type
	typedef C element_type;

	// Constructor. Defaults to initializing with NULL.
	// There is no way to create an uninitialized scoped_ptr.
	// The input parameter must be allocated with new.
	explicit scoped_ptr(C* p = NULL) : ptr_(p) { }

	// Destructor. If there is a C object, delete it.
	// We don't need to test ptr_ == NULL because C++ does that for us.
	~scoped_ptr() {
	enum { type_must_be_complete = sizeof(C) };
	delete ptr_;
	}

	// Reset. Deletes the current owned object, if any.
	// Then takes ownership of a new object, if given.
	// this->reset(this->get()) works.
	void reset(C* p = NULL) {
	if (p != ptr_) {
	enum { type_must_be_complete = sizeof(C) };
	delete ptr_;
	ptr_ = p;
	}
	}

	// Accessors to get the owned object.
	// operator* and operator-> will assert() if there is no current object.
	C& operator*() const {
	assert(ptr_ != NULL);
	return *ptr_;
	}
	C* operator->() const {
	assert(ptr_ != NULL);
	return ptr_;
	}
	C* get() const { return ptr_; }

	// Comparison operators.
	// These return whether two scoped_ptr refer to the same object, not just to
	// two different but equal objects.
	bool operator==(C* p) const { return ptr_ == p; }
	bool operator!=(C* p) const { return ptr_ != p; }

	// Swap two scoped pointers.
	void swap(scoped_ptr& p2) {
	C* tmp = ptr_;
	ptr_ = p2.ptr_;
	p2.ptr_ = tmp;
	}

	// Release a pointer.
	// The return value is the current pointer held by this object.
	// If this object holds a NULL pointer, the return value is NULL.
	// After this operation, this object will hold a NULL pointer,
	// and will not own the object any more.
	C* release() {
	C* retVal = ptr_;
	ptr_ = NULL;
	return retVal;
	}

	private:
	C* ptr_;

	// Forbid comparison of scoped_ptr types. If C2 != C, it totally doesn't
	// make sense, and if C2 == C, it still doesn't make sense because you should
	// never have the same object owned by two different scoped_ptrs.
	template <class C2> bool operator==(scoped_ptr<C2> const& p2) const;
	template <class C2> bool operator!=(scoped_ptr<C2> const& p2) const;

	// Disallow evil constructors
	scoped_ptr(const scoped_ptr&);
	void operator=(const scoped_ptr&);
	};

	// Free functions
	template <class C>
	void swap(scoped_ptr<C>& p1, scoped_ptr<C>& p2) {
	p1.swap(p2);
	}

	template <class C>
	bool operator==(C* p1, const scoped_ptr<C>& p2) {
	return p1 == p2.get();
	}

	template <class C>
	bool operator!=(C* p1, const scoped_ptr<C>& p2) {
	return p1 != p2.get();
	}

	// scoped_array<C> is like scoped_ptr<C>, except that the caller must allocate
	// with new [] and the destructor deletes objects with delete [].
	//
	// As with scoped_ptr<C>, a scoped_array<C> either points to an object
	// or is NULL. A scoped_array<C> owns the object that it points to.
	// scoped_array<T> is thread-compatible, and once you index into it,
	// the returned objects have only the threadsafety guarantees of T.
	//
	// Size: sizeof(scoped_array<C>) == sizeof(C*)
	template <class C>
	class scoped_array {
	public:

	// The element type
	typedef C element_type;

	// Constructor. Defaults to intializing with NULL.
	// There is no way to create an uninitialized scoped_array.
	// The input parameter must be allocated with new [].
	explicit scoped_array(C* p = NULL) : array_(p) { }

	// Destructor. If there is a C object, delete it.
	// We don't need to test ptr_ == NULL because C++ does that for us.
	~scoped_array() {
	enum { type_must_be_complete = sizeof(C) };
	delete[] array_;
	}

	// Reset. Deletes the current owned object, if any.
	// Then takes ownership of a new object, if given.
	// this->reset(this->get()) works.
	void reset(C* p = NULL) {
	if (p != array_) {
	enum { type_must_be_complete = sizeof(C) };
	delete[] array_;
	array_ = p;
	}
	}

	// Get one element of the current object.
	// Will assert() if there is no current object, or index i is negative.
	C& operator[](ptrdiff_t i) const {
	assert(i >= 0);
	assert(array_ != NULL);
	return array_[i];
	}

	// Get a pointer to the zeroth element of the current object.
	// If there is no current object, return NULL.
	C* get() const {
	return array_;
	}

	// Comparison operators.
	// These return whether two scoped_array refer to the same object, not just to
	// two different but equal objects.
	bool operator==(C* p) const { return array_ == p; }
	bool operator!=(C* p) const { return array_ != p; }

	// Swap two scoped arrays.
	void swap(scoped_array& p2) {
	C* tmp = array_;
	array_ = p2.array_;
	p2.array_ = tmp;
	}

	// Release an array.
	// The return value is the current pointer held by this object.
	// If this object holds a NULL pointer, the return value is NULL.
	// After this operation, this object will hold a NULL pointer,
	// and will not own the object any more.
	C* release() {
	C* retVal = array_;
	array_ = NULL;
	return retVal;
	}

	private:
	C* array_;

	// Forbid comparison of different scoped_array types.
	template <class C2> bool operator==(scoped_array<C2> const& p2) const;
	template <class C2> bool operator!=(scoped_array<C2> const& p2) const;

	// Disallow evil constructors
	scoped_array(const scoped_array&);
	void operator=(const scoped_array&);
	};

	// Free functions
	template <class C>
	void swap(scoped_array<C>& p1, scoped_array<C>& p2) {
	p1.swap(p2);
	}

	template <class C>
	bool operator==(C* p1, const scoped_array<C>& p2) {
	return p1 == p2.get();
	}

	template <class C>
	bool operator!=(C* p1, const scoped_array<C>& p2) {
	return p1 != p2.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<class C, class FreeProc = ScopedPtrMallocFree>
	class scoped_ptr_malloc {
	public:

	// The element type
	typedef C element_type;

	// Constructor. Defaults to initializing with NULL.
	// There is no way to create an uninitialized scoped_ptr.
	// The input parameter must be allocated with an allocator that matches the
	// Free functor. For the default Free functor, this is malloc, calloc, or
	// realloc.
	explicit scoped_ptr_malloc(C* p = NULL): ptr_(p) {}

	// Destructor. If there is a C object, call the Free functor.
	~scoped_ptr_malloc() {
	reset();
	}

	// Reset. Calls the Free functor on the current owned object, if any.
	// Then takes ownership of a new object, if given.
	// this->reset(this->get()) works.
	void reset(C* p = NULL) {
	if (ptr_ != p) {
	FreeProc free_proc;
	free_proc(ptr_);
	ptr_ = p;
	}
	}

	// Get the current object.
	// operator* and operator-> will cause an assert() failure if there is
	// no current object.
	C& operator*() const {
	assert(ptr_ != NULL);
	return *ptr_;
	}

	C* operator->() const {
	assert(ptr_ != NULL);
	return ptr_;
	}

	C* get() const {
	return ptr_;
	}

	// Comparison operators.
	// These return whether a scoped_ptr_malloc and a plain pointer refer
	// to the same object, not just to two different but equal objects.
	// For compatibility with the boost-derived implementation, these
	// take non-const arguments.
	bool operator==(C* p) const {
	return ptr_ == p;
	}

	bool operator!=(C* p) const {
	return ptr_ != p;
	}

	// Swap two scoped pointers.
	void swap(scoped_ptr_malloc & b) {
	C* tmp = b.ptr_;
	b.ptr_ = ptr_;
	ptr_ = tmp;
	}

	// Release a pointer.
	// The return value is the current pointer held by this object.
	// If this object holds a NULL pointer, the return value is NULL.
	// After this operation, this object will hold a NULL pointer,
	// and will not own the object any more.
	C* release() {
	C* tmp = ptr_;
	ptr_ = NULL;
	return tmp;
	}

	private:
	C* ptr_;

	// no reason to use these: each scoped_ptr_malloc should have its own object
	template <class C2, class GP>
	bool operator==(scoped_ptr_malloc<C2, GP> const& p) const;
	template <class C2, class GP>
	bool operator!=(scoped_ptr_malloc<C2, GP> const& p) const;

	// Disallow evil constructors
	scoped_ptr_malloc(const scoped_ptr_malloc&);
	void operator=(const scoped_ptr_malloc&);
	};

	template<class C, class FP> inline
	void swap(scoped_ptr_malloc<C, FP>& a, scoped_ptr_malloc<C, FP>& b) {
	a.swap(b);
	}

	template<class C, class FP> inline
	bool operator==(C* p, const scoped_ptr_malloc<C, FP>& b) {
	return p == b.get();
	}

	template<class C, class FP> inline
	bool operator!=(C* p, const scoped_ptr_malloc<C, FP>& b) {
	return p != b.get();
	}

	} // namespace google_breakpad

	#endif // COMMON_SCOPED_PTR_H_