A thread safe, header-only implementation of a smart pointer that deletes the contained object when not needed at the moment and recreates the object when needed again.

This is useful when resources are very rarely needed, when a resource is easy to create and delete, but difficult to maintain or when you want to defer the initialisation of a global variable to when it's actually needed.

I wrote this for an application that had two modes (1) didn't need a database connection (2) had to share a database connection between multiple threads. Using phoenix_ptr I could declare the connection in the containing namespace; in (1) the connection would stay unallocated, in (2) the first thread would open the connection and all other threads would reuse it too.

#include "softwear/phoenix_ptr.hpp"
softwear::phoenix_ptr<my_class> my_phoenix_instance;

See tests.cc for an example.

include/softwear/phoenix_ptr.hpp contains detailed documentation.

Run make.

• Allow using different types for mutex/lock_guard/weak_ptr/shared_ptr (e.g. the boost ones)
• Allow using an allocator
• Allow using creator/deleter functions
• Allow forwarding parameters
• Allow using some timeout?

Written by ([email protected]) Karolin Varner, for Softwear, BV (http://nl.softwear.nl/contact): You can still buy me a Club Mate. Or a coffee.

Copyright © (c) 2015, Softwear, BV. All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

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• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
• Neither the name of the Karolin Varner, Softwear, BV nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

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