shared-object.hpp
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/* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
/*
* Main authors:
* Christian Schulte <schulte@gecode.org>
*
* Copyright:
* Christian Schulte, 2017
*
* This file is part of Gecode, the generic constraint
* development environment:
* http://www.gecode.org
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*/
namespace Gecode {
class SharedHandle {
public:
class GECODE_KERNEL_EXPORT Object : public HeapAllocated {
friend class SharedHandle;
private:
Support::RefCount rc;
public:
Object(void);
virtual ~Object(void);
};
private:
Object* o;
void subscribe(void);
void cancel(void);
public:
SharedHandle(void);
SharedHandle(SharedHandle::Object* so);
SharedHandle(const SharedHandle& sh);
SharedHandle& operator =(const SharedHandle& sh);
~SharedHandle(void);
explicit operator bool(void) const;
protected:
SharedHandle::Object* object(void) const;
void object(SharedHandle::Object* n);
};
forceinline
SharedHandle::Object::Object(void)
: rc(0) {}
forceinline
SharedHandle::Object::~Object(void) {
assert(!rc);
}
forceinline SharedHandle::Object*
SharedHandle::object(void) const {
return o;
}
forceinline void
SharedHandle::subscribe(void) {
if (o != nullptr) o->rc.inc();
}
forceinline void
SharedHandle::cancel(void) {
if ((o != nullptr) && o->rc.dec())
delete o;
o=nullptr;
}
forceinline void
SharedHandle::object(SharedHandle::Object* n) {
if (n != o) {
cancel(); o=n; subscribe();
}
}
forceinline
SharedHandle::SharedHandle(void) : o(nullptr) {}
forceinline
SharedHandle::SharedHandle(SharedHandle::Object* so) : o(so) {
subscribe();
}
forceinline
SharedHandle::SharedHandle(const SharedHandle& sh) : o(sh.o) {
subscribe();
}
forceinline SharedHandle&
SharedHandle::operator =(const SharedHandle& sh) {
if (&sh != this) {
cancel(); o=sh.o; subscribe();
}
return *this;
}
forceinline
SharedHandle::operator bool(void) const {
return o != nullptr;
}
forceinline
SharedHandle::~SharedHandle(void) {
cancel();
}
}
// STATISTICS: kernel-memory
Gecode::HeapAllocated
Base class for heap allocated objects.
Definition heap.hpp:340
Gecode::SharedHandle::Object
The shared object.
Definition shared-object.hpp:53
Gecode::SharedHandle::Object::~Object
virtual ~Object(void)
Delete shared object.
Definition shared-object.hpp:96
Gecode::SharedHandle::Object::SharedHandle
friend class SharedHandle
Definition shared-object.hpp:54
Gecode::SharedHandle::Object::Object
Object(void)
Initialize.
Definition shared-object.hpp:93
Gecode::SharedHandle
The shared handle.
Definition shared-object.hpp:46
Gecode::SharedHandle::operator=
SharedHandle & operator=(const SharedHandle &sh)
Assignment operator maintaining reference count.
Definition shared-object.hpp:132
Gecode::SharedHandle::SharedHandle
SharedHandle(void)
Create shared handle with no object pointing to.
Definition shared-object.hpp:122
Gecode::SharedHandle::object
SharedHandle::Object * object(void) const
Access to the shared object.
Definition shared-object.hpp:102
Gecode::SharedHandle::~SharedHandle
~SharedHandle(void)
Destructor that maintains reference count.
Definition shared-object.hpp:143
Gecode::Support::RefCount
A class for thread-safe reference counting.
Definition ref-count.hpp:39
Gecode::Support::RefCount::dec
bool dec(void)
Decrement counter and return true if it hits zero.
Definition ref-count.hpp:63
Gecode::Support::RefCount::inc
void inc(void)
Increment counter.
Definition ref-count.hpp:59
GECODE_KERNEL_EXPORT
#define GECODE_KERNEL_EXPORT
Definition kernel.hh:70
Gecode
Gecode toplevel namespace
forceinline
#define forceinline
Definition config.hpp:187