Re: [PATCH] oidmap: map with OID as key

[Brandon Williams <bmwill@google.com>]

On 09/27, Jonathan Tan wrote:
> This is similar to using the hashmap in hashmap.c, but with an
> easier-to-use API. In particular, custom entry comparisons no longer
> need to be written, and lookups can be done without constructing a
> temporary entry structure.
> 
> oidset has been updated to use oidmap.

After a quick glance at the code, I think it looks good.  I do have one
suggestion though.  This map is structured much like our internal
hashmap where if you want to include any data you have to implement your
own struct with the internal 'entry' struct as the first member in your
custom struct.  I personal dislike this method, despite the potential
memory savings, because it makes the data structure much more difficult
to use.

If all i wanted was a map from 'OID -> const char *' then I would need
to write all the boilerplate code to make a struct which contains the
map 'entry' struct + the 'const char *' entry.  You are also making the
caller responsible for allocating the individual entries instead of
letting the data structure take care of that internally.

To me it seems like a much simpler API for a map would be to just allow
callers to store a 'void *' as the value.

-- 
Brandon Williams