Re: [boost] [Review] Shmem Library

From: Ion Gaztañaga (igaztanaga_at_[hidden])
Date: 2006-02-09 12:08:55

 >When I first thought about it, the approach that I considered was to
 >use two classes. mmaped_file represents a file which has zero or more
 >mmaped regions, and mmaped_region which represents a single region. the
 >Off top of my head, something like this might be appropriate:

I see. Another possibility is a "mmapped_file" class that produces 
"file_mappings". However this has not the lifetime security your 
approach has, since your mapped_file won't be destroyed until the last 
mapped_region is destroyed. However, being from the old school, I don't 
like much the mandatory use of shared_ptr in the interface (so that 
mapped_file must be allocated only via new). Anyway, I get the idea of 
two separate concepts and I can see that your approach saves a lot of 
lifetime issues, and I don't think file_mappings will be objects that 
will be created and destroyed very heavily. file_mappings could have 
also ordering operators so that we can store them in containers.

I think both your mapping approach and boost::shmem::mmapped_file can be 
complementary, being boost::shmem::mmapped_file for simple uses and this 
multi-mapping approach for advanced ones. If you want to implement it, 
I'm ready to help or if you just want to help, I'm ready to implement it 
for a future Shmem version.

Thanks,

Ion