Re: [PATCH] for-each-ref: delay parsing of --sort=<atom> options
- From
Jeff King <peff@peff.net>
- Date
- Oct 20, 2021, 02:20 UTC
- Message-ID
- <YW98+Lj9xVsR9u9Q@coredump.intra.peff.net>
- In-Reply-To
- <YW9EP5UNX0f+eOke@coredump.intra.peff.net>
On Tue, Oct 19, 2021 at 06:18:40PM -0400, Jeff King wrote:
Show 28 quoted lines
> > @@ -86,8 +86,6 @@ int cmd_ls_remote(int argc, const char **argv, const char *prefix)
> >
> > packet_trace_identity("ls-remote");
> >
> > - UNLEAK(sorting);
> > -
> > if (argc > 1) {
> > int i;
> > CALLOC_ARRAY(pattern, argc);
> > @@ -139,8 +137,13 @@ int cmd_ls_remote(int argc, const char **argv, const char *prefix)
> > item->symref = xstrdup_or_null(ref->symref);
> > }
> >
> > - if (sorting)
> > + if (sorting_options.nr) {
> > + struct ref_sorting *sorting;
> > + UNLEAK(sorting);
> > +
> > + sorting = ref_sorting_options(&sorting_options);
> > ref_array_sort(sorting, &ref_array);
> > + }
>
> I wondered at first about pulling this UNLEAK() down, but it's because
> you move the "sorting" variable itself into the smaller scope. So this
> makes sense (and calling UNLEAK() before the pointer is set is perfectly
> fine, since it takes the address of the auto variable). It is a shame
> you can't just ref_sorting_free() afterwards, but we don't have that
> function yet. And adding it is way out of scope here. :)Actually, I think I was wrong here. UNLEAK() will look at &sorting, but it will snapshot its data at the time of the call. So it won't do anything when the variable doesn't yet have a value.
You can demonstrate with:
$ make SANITIZE=leak $ ./git ls-remote --sort=refname .
which will complain. Bumping it down like this:
diff --git a/builtin/ls-remote.c b/builtin/ls-remote.c index 1e6017cdaa..a94a220256 100644 --- a/builtin/ls-remote.c +++ b/builtin/ls-remote.c @@ -139,10 +139,10 @@ int cmd_ls_remote(int argc, const char **argv, const char *prefix) if (sorting_options.nr) { struct ref_sorting *sorting; - UNLEAK(sorting); sorting = ref_sorting_options(&sorting_options); ref_array_sort(sorting, &ref_array); + UNLEAK(sorting); } for (i = 0; i < ref_array.nr; i++) { clears it up. Note that there are other similar "leaks" (e.g., if you give a pattern in argv[1]) which should be punted to another topic, but I think you'd want to deal with this one since you're moving the UNLEAK() around. -Peff