nub::ref_counted Class Reference
#include <nub/refcounted.h>
Public Member Functions | |
| void * | operator new (size_t bytes) |
| void | operator delete (void *space, size_t bytes) |
| ref_counted () | |
| Default constructor. | |
| virtual | ~ref_counted () GVX_DTOR_NOTHROW |
| void | mark_as_volatile () throw () |
| Mark this object as a volatile (unshareable) object. | |
| void | incr_ref_count () const throw () |
| Increment the object's reference count. | |
| void | decr_ref_count () const throw () |
| Decrement the object's reference count. | |
| void | decr_ref_count_no_delete () const throw () |
| Decrement the object's reference count, but don't delete it. | |
| bool | is_shared () const throw () |
| Returns true if no external client has sole ownership of the object. | |
| bool | is_unshared () const throw () |
| Returns true if there is a sole external owner of the object. | |
| bool | is_not_shareable () const throw () |
| ref_counts * | get_counts () const throw () |
| Returns the object's reference count manager. | |
| int | dbg_ref_count () const throw () |
| FOR TEST/DEBUG ONLY! Returns the object's (strong) reference count. | |
| int | dbg_weak_ref_count () const throw () |
| FOR TEST/DEBUG ONLY! Returns the object's weak reference count. | |
Detailed Description
nub::ref_counted is a reference counting base class that allows both strong and weak reference counting. nub::ref_counted objects use a nub::ref_counts object to manage their reference counts, so clients that need to know if a nub::ref_counted object is still around can check the is_owner_alive() from its nub::ref_counts object. Finally, subclasses of nub::ref_counted can declare themselves volatile (by calling mark_as_volatile()) if their lifetime cannot be fully controlled by reference-counting; clients of such volatile objects must use weak reference counts only. No manipulation of the reference count is allowed for volatile objects; only the weak reference count may be used.Definition at line 129 of file refcounted.h.
Constructor & Destructor Documentation
| nub::ref_counted::~ref_counted | ( | ) | [virtual] |
Virtual destructor is protected, so that we can prevent clients from instantiating ref_counted's on the stack and from destroying them explicitly. Instead, ref_counted objects will only be destroyed by a 'delete this' call inside decr_ref_count() if the reference count falls to zero or below. Clients are forced to create ref_counted objects dynamically using new, which is what we need in order for 'delete this' to be valid later on.
Definition at line 178 of file refcounted.cc.
References rutz::mutex_atomic_int::atomic_get(), GVX_PANIC, nub::ref_counts::m_owner_alive, nub::ref_counts::m_strong, and nub::ref_counts::release_weak().
Member Function Documentation
| void * nub::ref_counted::operator new | ( | size_t | bytes | ) |
Class-specific operator new; protected to ensure that clients use factory functions.
Definition at line 157 of file refcounted.cc.
| void nub::ref_counted::operator delete | ( | void * | space, | |
| size_t | bytes | |||
| ) |
Class-specific operator delete; private since deletion should only happen in ref_counted::decr_ref_count.
Definition at line 163 of file refcounted.cc.
| void nub::ref_counted::incr_ref_count | ( | ) | const throw () |
Increment the object's reference count.
This operation (on the strong reference count) is not permitted if the object is unshareable. Unshareable objects can only have their weak reference counts manipulated.
Definition at line 207 of file refcounted.cc.
References nub::ref_counts::acquire_strong().
Referenced by GxEmptyNode::make().
| void nub::ref_counted::decr_ref_count | ( | ) | const throw () |
Decrement the object's reference count.
If this causes the reference count to fall to zero or below, the pointee and the pointer will be destroyed by a call to 'delete this'. This operation (on the strong reference count) is not permitted if the object is unshareable. Unshareable objects can only have their weak reference counts manipulated.
Definition at line 212 of file refcounted.cc.
References nub::ref_counts::release_strong().
| void nub::ref_counted::decr_ref_count_no_delete | ( | ) | const throw () |
Decrement the object's reference count, but don't delete it.
Unlike decr_ref_count(), the object will NOT be delete'd if the reference count falls to zero. This operation (on the strong reference count) is not permitted if the object is unshareable. Unshareable objects can only have their weak reference counts manipulated.
Definition at line 221 of file refcounted.cc.
References nub::ref_counts::release_strong_no_delete().
| bool nub::ref_counted::is_shared | ( | ) | const throw () |
Returns true if no external client has sole ownership of the object.
This may occur if either (1) the reference count is greater than one, or (2) the object is_not_shareable(), meaning that the object itself is the only "owner".
Definition at line 226 of file refcounted.cc.
References rutz::mutex_atomic_int::atomic_get(), is_not_shareable(), and nub::ref_counts::m_strong.
Referenced by is_unshared().
| bool nub::ref_counted::is_unshared | ( | ) | const throw () |
Returns true if there is a sole external owner of the object.
This occurs if the reference count is one or less and the object is shareable.
Definition at line 236 of file refcounted.cc.
References is_shared().
| bool nub::ref_counted::is_not_shareable | ( | ) | const throw () |
Returns true if the object is not shareable for any reason. This could be because its lifespan is volatile (such as objects representing on-screen windows that can be dismissed by the user). The default is for objects to be shareable; objects can declare themselves as unshareable by calling mark_as_volatile().
Definition at line 242 of file refcounted.cc.
References nub::ref_counts::m_volatile.
Referenced by is_shared().
The documentation for this class was generated from the following files:
- src/nub/refcounted.h
- src/nub/refcounted.cc