@matheusbsbs / matheus-bagliano / commits / 01aff0ae85

apply: correctly reverse patch's pre- and post-image mode bits

When parsing the patch header, unless it is a patch that changes file modes, we only read the mode bits into the .old_mode member of the patch structure and leave .new_mode member as initialized, i.e., to 0. Later when we need the original mode bits, we consult .old_mode. However, reverse_patches() that is used to swap the names and modes of the preimage and postimage files is not aware of this convention, leading the .old_mode to be 0 while the mode we read from the patch is left in .new_mode. Only swap .old_mode and .new_mode when .new_mode is not 0 (i.e. we saw a patch that modifies the filemode and know what the new mode is). When .new_mode is set to 0, it means the preimage and the postimage files have the same mode (which is in the .old_mode member) and when applying such a patch in reverse, the value in .old_mode is what we expect the (reverse-) preimage file to have. Reported-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Junio C Hamano committed Dec 26, 2023 at 15:32 UTC 01aff0ae85af100c4d88df753078158b82774ea0

1 file changed +4 -4

apply.c

+4 -4

@@ -2220,7 +2220,8 @@ static void reverse_patches(struct patch *p)

2220 struct fragment *frag = p->fragments;

2221

2222 SWAP(p->new_name, p->old_name);

2223 - SWAP(p->new_mode, p->old_mode);

2223 + if (p->new_mode)

2224 + SWAP(p->new_mode, p->old_mode);

2225 SWAP(p->is_new, p->is_delete);

2226 SWAP(p->lines_added, p->lines_deleted);

2227 SWAP(p->old_oid_prefix, p->new_oid_prefix);

@@ -3780,9 +3781,8 @@ static int check_preimage(struct apply_state *state,

3781

3782 if (!state->cached && !previous) {

3783 if (!trust_executable_bit)

3783 - st_mode = (*ce && (*ce)->ce_mode) ? (*ce)->ce_mode :

3784 - (state->apply_in_reverse

3785 - ? patch->new_mode : patch->old_mode);

3784 + st_mode = (*ce && (*ce)->ce_mode)

3785 + ? (*ce)->ce_mode : patch->old_mode;

3786 else

3787 st_mode = ce_mode_from_stat(*ce, st->st_mode);

3788 }