mirror of
https://github.com/FirebirdSQL/firebird.git
synced 2025-01-31 13:23:02 +01:00
90 lines
2.5 KiB
C++
90 lines
2.5 KiB
C++
/*
|
||
* PROGRAM: JRD Access Method
|
||
* MODULE: auto.h
|
||
* DESCRIPTION: STL::auto_ptr replacement
|
||
*
|
||
* *** warning ***
|
||
* Unlike STL's auto_ptr ALWAYS deletes ptr in destructor -
|
||
* no ownership flag!
|
||
*
|
||
* The contents of this file are subject to the Initial
|
||
* Developer's Public License Version 1.0 (the "License");
|
||
* you may not use this file except in compliance with the
|
||
* License. You may obtain a copy of the License at
|
||
* http://www.ibphoenix.com/main.nfs?a=ibphoenix&page=ibp_idpl.
|
||
*
|
||
* Software distributed under the License is distributed AS IS,
|
||
* WITHOUT WARRANTY OF ANY KIND, either express or implied.
|
||
* See the License for the specific language governing rights
|
||
* and limitations under the License.
|
||
*
|
||
* The Original Code was created by Alexander Peshkoff
|
||
* for the Firebird Open Source RDBMS project.
|
||
*
|
||
* Copyright (c) 2004 Alexander Peshkoff <peshkoff@mail.ru>
|
||
* and all contributors signed below.
|
||
*
|
||
* All Rights Reserved.
|
||
* Contributor(s): ______________________________________.
|
||
*/
|
||
|
||
#ifndef CLASSES_AUTO_PTR_H
|
||
#define CLASSES_AUTO_PTR_H
|
||
|
||
namespace Firebird {
|
||
|
||
template <typename What>
|
||
class SimpleDelete
|
||
{
|
||
public:
|
||
static void clear(What *ptr)
|
||
{
|
||
delete ptr;
|
||
}
|
||
};
|
||
|
||
template <typename Where, typename Clear = SimpleDelete<Where> >
|
||
class AutoPtr {
|
||
private:
|
||
Where* ptr;
|
||
public:
|
||
AutoPtr<Where, Clear>(Where* v) {ptr = v;}
|
||
operator Where*() {return ptr;}
|
||
operator bool() {return ptr ? true : false;}
|
||
operator !() {return ptr ? false : true;}
|
||
Where* operator->() {return ptr;}
|
||
~AutoPtr<Where, Clear>() {Clear::clear(ptr);}
|
||
};
|
||
|
||
// CVC: It turns out that AutoPtr was designed to deallocate single objects,
|
||
// not arrays. Worse even, we need in many places to allocate dynamically an
|
||
// array of char*/UCHAR* that's later converted into a pointer to a single
|
||
// object and passed to AutoPtr. In that case, AutoPtr will invoke the wrong
|
||
// deallocation logic and therefore we have undefined behavior, typically a leak.
|
||
// See execute_statement.cpp for an example. This is the reason this
|
||
// AutoPtrFromString beast was created.
|
||
// Alex: It should be gone after full <20>++ code conversion
|
||
|
||
template <typename What>
|
||
class CharArrayDelete
|
||
{
|
||
public:
|
||
static void clear(What *ptr)
|
||
{
|
||
delete reinterpret_cast<char*>(ptr);
|
||
}
|
||
};
|
||
|
||
template <typename Where>
|
||
class AutoPtrFromString : public AutoPtr<Where, CharArrayDelete<Where> >
|
||
{
|
||
public:
|
||
AutoPtrFromString<Where>(Where *v)
|
||
: AutoPtr<Where, CharArrayDelete<Where> >(v) { }
|
||
};
|
||
|
||
} //namespace Firebird
|
||
|
||
#endif // CLASSES_AUTO_PTR_H
|
||
|