On Sun, May 19, 2013 at 10:27 PM, Michael Haggerty <mhagger@xxxxxxxxxxxx> wrote:
> This is the culmination of the last few commits. Since some callers
> want to store refnames in the name field of object_array elements, but
> we don't want those callers to assume that the refnames that they got
> from for_each_ref() have infinite lifetime, the easiest thing to do is
> have object_array make a copy of the names before writing them in the
> entries, and to free the names for entries that are no longer in use.
> This change fixes the problem, but has some disadvantages:
>
> * It requires extra copies to be made of strings that are already
> copies, for example when the results of path_name(path, name) are
> used as a name in revision.c:add_object(). This might be rare
> enough that it can be ignored (though the original result of
> path_name() would have to be freed, which this patch doesn't do so
> there is a memory leak).
>
> * Many callers store the empty string ("") as the name; for example,
> most of the entries created during a run of rev-list have "" as
> their name. This means that lots of needless copies of "" are being
> made. I think that the best solution to this problem would be to
> store NULL rather than "" for such entries, but I haven't figured
> out all of the places where the name is used.
Use strbufs?
No allocation (except for the strbuf object itself) is needed for
empty strings, and string ownership and be transferred to and from it
to prevent extra copies.
...Johan
--
Johan Herland, <johan@xxxxxxxxxxx>
www.herland.net
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