checkout: avoid "struct unpack_trees_options" leak

Git fork

In 1c41d2805e4 (unpack_trees_options: free messages when done,
2018-05-21) we started calling clear_unpack_trees_porcelain() on this
codepath, but missed this error path.

We could call clear_unpack_trees_porcelain() just before we error()
and return when unmerged_cache() fails, but the more correct fix is to
not have the unmerged_cache() check happen in the middle of our
"topts" setup.

Before 23cbf11b5c0 (merge-recursive: porcelain messages for checkout,
2010-08-11) we would not malloc() to setup our "topts", which is when
this started to leak on the error path.

Before that this code wasn't conflating the setup of "topts" and the
unmerged_cache() call in any meaningful way. The initial version in
782c2d65c24 (Build in checkout, 2008-02-07) just does a "memset" of
it, and initializes a single struct member.

Then in 8ccba008ee3 (unpack-trees: allow Porcelain to give different
error messages, 2008-05-17) we added the initialization of the error
message, which as noted above finally started leaking in 23cbf11b5c0.

Let's fix the memory leak, and avoid future issues by initializing the
"topts" with a helper function. There are no functional changes here.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

authored by

Ævar Arnfjörð Bjarmason and committed by

Junio C Hamano 3 years ago 33d0dda6 e72e12cc

+22 -14

1 changed file

expand all

builtin

checkout.c

+22 -14

builtin/checkout.c

··· 710 710 branch->path = strbuf_detach(&buf, NULL); 711 711 } 712 712 713 + static void init_topts(struct unpack_trees_options *topts, int merge, 714 + int show_progress, int overwrite_ignore, 715 + struct commit *old_commit) 716 + { 717 + memset(topts, 0, sizeof(*topts)); 718 + topts->head_idx = -1; 719 + topts->src_index = &the_index; 720 + topts->dst_index = &the_index; 721 + 722 + setup_unpack_trees_porcelain(topts, "checkout"); 723 + 724 + topts->initial_checkout = is_cache_unborn(); 725 + topts->update = 1; 726 + topts->merge = 1; 727 + topts->quiet = merge && old_commit; 728 + topts->verbose_update = show_progress; 729 + topts->fn = twoway_merge; 730 + topts->preserve_ignored = !overwrite_ignore; 731 + } 732 + 713 733 static int merge_working_tree(const struct checkout_opts *opts, 714 734 struct branch_info *old_branch_info, 715 735 struct branch_info *new_branch_info, ··· 740 760 struct unpack_trees_options topts; 741 761 const struct object_id *old_commit_oid; 742 762 743 - memset(&topts, 0, sizeof(topts)); 744 - topts.head_idx = -1; 745 - topts.src_index = &the_index; 746 - topts.dst_index = &the_index; 747 - 748 - setup_unpack_trees_porcelain(&topts, "checkout"); 749 - 750 763 refresh_cache(REFRESH_QUIET); 751 764 752 765 if (unmerged_cache()) { ··· 755 768 } 756 769 757 770 /* 2-way merge to the new branch */ 758 - topts.initial_checkout = is_cache_unborn(); 759 - topts.update = 1; 760 - topts.merge = 1; 761 - topts.quiet = opts->merge && old_branch_info->commit; 762 - topts.verbose_update = opts->show_progress; 763 - topts.fn = twoway_merge; 771 + init_topts(&topts, opts->merge, opts->show_progress, 772 + opts->overwrite_ignore, old_branch_info->commit); 764 773 init_checkout_metadata(&topts.meta, new_branch_info->refname, 765 774 new_branch_info->commit ? 766 775 &new_branch_info->commit->object.oid : 767 776 &new_branch_info->oid, NULL); 768 - topts.preserve_ignored = !opts->overwrite_ignore; 769 777 770 778 old_commit_oid = old_branch_info->commit ? 771 779 &old_branch_info->commit->object.oid :