rebase: pass correct arguments to post-checkout hook
If a rebase started with "rebase [--apply|--merge] <upstream> <branch>" detects that <upstream> is an ancestor of <branch> then it fast-forwards and checks out <branch>. Unfortunately in that case it passed the null oid as the first argument to the post-checkout hook rather than the oid of HEAD. A side effect of this change is that the call to update_ref() which updates HEAD now always receives the old value of HEAD. This provides protection against another process updating HEAD during the checkout. Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Phillip Wood committed
Jan 26, 2022 at 13:05 UTC
69f4c23009ee30faeb61a831f4265791c945783e
2 files changed
+22
-9
reset.c
+9
-9
@@ -18,7 +18,7 @@ int reset_head(struct repository *r, struct object_id *oid, const char *action,
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unsigned run_hook = flags & RESET_HEAD_RUN_POST_CHECKOUT_HOOK;
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unsigned refs_only = flags & RESET_HEAD_REFS_ONLY;
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unsigned update_orig_head = flags & RESET_ORIG_HEAD;
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- struct object_id head_oid;
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+ struct object_id *head = NULL, head_oid;
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struct tree_desc desc[2] = { { NULL }, { NULL } };
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struct lock_file lock = LOCK_INIT;
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struct unpack_trees_options unpack_tree_opts = { 0 };
@@ -26,8 +26,7 @@ int reset_head(struct repository *r, struct object_id *oid, const char *action,
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const char *reflog_action;
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struct strbuf msg = STRBUF_INIT;
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size_t prefix_len;
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- struct object_id *orig = NULL, oid_orig,
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- *old_orig = NULL, oid_old_orig;
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+ struct object_id *old_orig = NULL, oid_old_orig;
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int ret = 0, nr = 0;
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if (switch_to_branch && !starts_with(switch_to_branch, "refs/"))
@@ -38,7 +37,9 @@ int reset_head(struct repository *r, struct object_id *oid, const char *action,
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goto leave_reset_head;
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}
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- if ((!oid || !reset_hard) && get_oid("HEAD", &head_oid)) {
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+ if (!get_oid("HEAD", &head_oid)) {
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+ head = &head_oid;
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+ } else if (!oid || !reset_hard) {
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ret = error(_("could not determine HEAD revision"));
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goto leave_reset_head;
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}
@@ -98,13 +99,12 @@ reset_head_refs:
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if (update_orig_head) {
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if (!get_oid("ORIG_HEAD", &oid_old_orig))
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old_orig = &oid_old_orig;
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- if (!get_oid("HEAD", &oid_orig)) {
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- orig = &oid_orig;
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+ if (head) {
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if (!reflog_orig_head) {
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strbuf_addstr(&msg, "updating ORIG_HEAD");
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reflog_orig_head = msg.buf;
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}
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- update_ref(reflog_orig_head, "ORIG_HEAD", orig,
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+ update_ref(reflog_orig_head, "ORIG_HEAD", head,
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old_orig, 0, UPDATE_REFS_MSG_ON_ERR);
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} else if (old_orig)
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delete_ref(NULL, "ORIG_HEAD", old_orig, 0);
@@ -116,7 +116,7 @@ reset_head_refs:
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reflog_head = msg.buf;
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}
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if (!switch_to_branch)
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- ret = update_ref(reflog_head, "HEAD", oid, orig,
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+ ret = update_ref(reflog_head, "HEAD", oid, head,
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detach_head ? REF_NO_DEREF : 0,
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UPDATE_REFS_MSG_ON_ERR);
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else {
@@ -128,7 +128,7 @@ reset_head_refs:
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}
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if (run_hook)
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run_hook_le(NULL, "post-checkout",
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- oid_to_hex(orig ? orig : null_oid()),
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+ oid_to_hex(head ? head : null_oid()),
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oid_to_hex(oid), "1", NULL);
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leave_reset_head:
t/t5403-post-checkout-hook.sh
+13
@@ -72,6 +72,19 @@ test_rebase () {
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test_cmp_rev rebase-on-me $new &&
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test $flag = 1
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'
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+
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+ test_expect_success "rebase $args fast-forward branch checkout runs post-checkout hook" '
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+ test_when_finished "test_might_fail git rebase --abort" &&
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+ test_when_finished "rm -f .git/post-checkout.args" &&
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+ git update-ref refs/heads/rebase-fast-forward three &&
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+ git checkout two &&
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+ rm -f .git/post-checkout.args &&
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+ git rebase $args HEAD rebase-fast-forward &&
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+ read old new flag <.git/post-checkout.args &&
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+ test_cmp_rev two $old &&
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+ test_cmp_rev three $new &&
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+ test $flag = 1
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+ '
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}
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test_rebase --apply &&