Fawkes API  Fawkes Development Version
autofree.cpp
1 
2 /***************************************************************************
3  * autofree.cpp - Automatic Freeer
4  *
5  * Created: Thu Nov 26 13:17:42 2009
6  * Copyright 2005-2009 Tim Niemueller [www.niemueller.de]
7  *
8  ****************************************************************************/
9 
10 /* This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version. A runtime exception applies to
14  * this software (see LICENSE.GPL_WRE file mentioned below for details).
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19  * GNU Library General Public License for more details.
20  *
21  * Read the full text in the LICENSE.GPL_WRE file in the doc directory.
22  */
23 
24 #include <utils/misc/autofree.h>
25 
26 #include <cstdlib>
27 
28 namespace fawkes {
29 
30 /** @class MemAutoFree <utils/misc/autofree.h>
31  * Automatically free memory on destruction.
32  * This class can be used to free memory on destruction of the object.
33  * This is similar to many use cases of std::auto_ptr, with the difference
34  * that it calls free() to release the memory instead of delete, therefore
35  * it is meant to be used with classical memory allocations, e.g. C strings.
36  * In effect the instance of MemAutoFree takes ownership of the passed pointer.
37  * @author Tim Niemueller
38  */
39 
40 /** Constructor.
41  * @param ptr pointer to delete on destruct
42  */
43 MemAutoFree::MemAutoFree(void *ptr)
44 {
45  ptr_ = ptr;
46 }
47 
48 /** Destructor.
49  * Destroys the memory chunk unless it has been released before.
50  */
52 {
53  if (ptr_)
54  free(ptr_);
55 }
56 
57 /** Release ownership.
58  * The instance no longer owns the pointer and memory will not be deleted
59  * on destruction.
60  */
61 void
63 {
64  ptr_ = NULL;
65 }
66 
67 /** Reset pointer to a different one,
68  * This will free the pointer hold up to this call and will replace it with
69  * new_ptr. It is verified that the old and new pointers are different, nothing
70  * will be done if they are the same.
71  * @param new_ptr new pointer to own
72  */
73 void
74 MemAutoFree::reset(void *new_ptr)
75 {
76  if (ptr_ != new_ptr) {
77  if (ptr_)
78  free(ptr_);
79  ptr_ = new_ptr;
80  }
81 }
82 
83 /** Access memory pointer.
84  * @return pointer to memory, maybe NULL
85  */
86 void *MemAutoFree::operator*() const
87 {
88  return ptr_;
89 }
90 
91 } // end namespace fawkes
fawkes::MemAutoFree::release
void release()
Release ownership.
Definition: autofree.cpp:66
fawkes::MemAutoFree::~MemAutoFree
~MemAutoFree()
Destructor.
Definition: autofree.cpp:55
fawkes::MemAutoFree::operator*
void * operator*() const
Access memory pointer.
Definition: autofree.cpp:90
fawkes::MemAutoFree::MemAutoFree
MemAutoFree(void *ptr)
Constructor.
Definition: autofree.cpp:47
fawkes
fawkes::MemAutoFree::reset
void reset(void *new_ptr)
Reset pointer to a different one, This will free the pointer hold up to this call and will replace it...
Definition: autofree.cpp:78