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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.
// scoped_ptr_malloc added in 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 in by Google. Use this to conditionally
// transfer ownership of a heap-allocated object to the caller, usually on
// method success.
#ifndef TALK_BASE_SCOPED_PTR_H__
#define TALK_BASE_SCOPED_PTR_H__
#include <cstddef> // for std::ptrdiff_t
#include <stdlib.h> // for free() decl
#include "talk/base/common.h" // for ASSERT
#ifdef _WIN32
namespace std { using ::ptrdiff_t; };
#endif // _WIN32
namespace talk_base {
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 = NULL): ptr(p) {}
~scoped_ptr() {
typedef char type_must_be_complete[sizeof(T)];
delete ptr;
}
void reset(T* p = NULL) {
typedef char type_must_be_complete[sizeof(T)];
if (ptr != p) {
T* obj = ptr;
ptr = p;
// Delete last, in case obj destructor indirectly results in ~scoped_ptr
delete obj;
}
}
T& operator*() const {
ASSERT(ptr != NULL);
return *ptr;
}
T* operator->() const {
ASSERT(ptr != NULL);
return ptr;
}
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 = NULL;
return tmp;
}
T** accept() {
if (ptr) {
delete ptr;
ptr = NULL;
}
return &ptr;
}
T** use() {
return &ptr;
}
};
template<typename T> inline
void swap(scoped_ptr<T>& a, scoped_ptr<T>& b) {
a.swap(b);
}
// 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 = NULL) : ptr(p) {}
~scoped_array() {
typedef char type_must_be_complete[sizeof(T)];
delete[] ptr;
}
void reset(T* p = NULL) {
typedef char type_must_be_complete[sizeof(T)];
if (ptr != p) {
T* arr = ptr;
ptr = p;
// Delete last, in case arr destructor indirectly results in ~scoped_array
delete [] arr;
}
}
T& operator[](std::ptrdiff_t i) const {
ASSERT(ptr != NULL);
ASSERT(i >= 0);
return ptr[i];
}
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 = NULL;
return tmp;
}
T** accept() {
if (ptr) {
delete [] ptr;
ptr = NULL;
}
return &ptr;
}
};
template<class T> inline
void swap(scoped_array<T>& a, scoped_array<T>& b) {
a.swap(b);
}
// scoped_ptr_malloc<> is similar to scoped_ptr<>, but it accepts a
// second template argument, the function used to free the object.
template<typename T, void (*FF)(void*) = free> 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() {
FF(static_cast<void*>(ptr));
}
void reset(T* p = 0) {
if (ptr != p) {
FF(static_cast<void*>(ptr));
ptr = p;
}
}
T& operator*() const {
ASSERT(ptr != 0);
return *ptr;
}
T* operator->() const {
ASSERT(ptr != 0);
return ptr;
}
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;
}
T** accept() {
if (ptr) {
FF(static_cast<void*>(ptr));
ptr = 0;
}
return &ptr;
}
};
template<typename T, void (*FF)(void*)> inline
void swap(scoped_ptr_malloc<T,FF>& a, scoped_ptr_malloc<T,FF>& b) {
a.swap(b);
}
} // namespace talk_base
#endif // #ifndef TALK_BASE_SCOPED_PTR_H__