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Date:   Tue, 16 Jun 2020 08:45:02 -0400
From:   Jeff King <peff@peff.net>
To:     Eric Sunshine <sunshine@sunshineco.com>
Cc:     Don Goodman-Wilson via GitGitGadget <gitgitgadget@gmail.com>,
        Git List <git@vger.kernel.org>,
        Derrick Stolee <stolee@gmail.com>,
        "brian m. carlson" <sandals@crustytoothpaste.net>,
        Johannes Schindelin <johannes.schindelin@gmx.de>,
        Don Goodman-Wilson <don@goodman-wilson.com>
Subject: Re: [PATCH 1/9] init: allow overriding the default branch name for
 new repositories
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On Wed, Jun 10, 2020 at 08:16:38PM -0400, Eric Sunshine wrote:

> > +/*
> > + * Retrieves the name of the default branch. If `short_name` is non-zero, the
> > + * branch name will be prefixed with "refs/heads/".
> > + */
> > +char *git_default_branch_name(int short_name);
> 
> Overall, the internal logic regarding duplicating/freeing strings
> would probably be easier to grok if there were two separate functions:
> 
>     char *git_default_branch_name(void);
>     char *git_default_ref_name(void);
> 
> but that's subjective.

Having seen one of the callers, might it be worth avoiding handing off
ownership of the string entirely?

I.e., this comes from a string that's already owned for the lifetime of
the process (either the environment, or a string stored by the config
machinery). Could we just pass that back (or if we want to be more
careful about getenv() lifetimes, we can copy it into a static owned by
this function)?

Then all of the callers can stop dealing with the extra free(), and you
can do:

  const char *git_default_branch_name(void)
  {
	return skip_prefix("refs/heads/", git_default_ref_name());
  }

-Peff