Re: [PATCH v2] range-diff: don't segfault with mode-only changes

> In ef283b3699 ("apply: make parse_git_diff_header public", 2019-07-11)
> the 'parse_git_diff_header' function was made public and useable by
> callers outside of apply.c.
> 
> However it was missed that its (then) only caller, 'find_header' did
> some error handling, and completing 'struct patch' appropriately.
> 
> range-diff then started using this function, and tried to handle this
> appropriately itself, but fell short in some cases.  This in turn
> would lead to range-diff segfaulting when there are mode-only changes
> in a range.
> 
> Move the error handling and completing of the struct into the
> 'parse_git_diff_header' function, so other callers can take advantage
> of it.  This fixes the segfault in 'git range-diff'.
> 
> Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> Signed-off-by: Thomas Gummerer <t.gummerer@gmail.com>