Merge branch 'js/merge-base-with-missing-commit'

Make sure failure return from merge_bases_many() is properly caught.

* js/merge-base-with-missing-commit:
  merge-ort/merge-recursive: do report errors in `merge_submodule()`
  merge-recursive: prepare for `merge_submodule()` to report errors
  commit-reach(repo_get_merge_bases_many_dirty): pass on errors
  commit-reach(repo_get_merge_bases_many): pass on "missing commits" errors
  commit-reach(get_octopus_merge_bases): pass on "missing commits" errors
  commit-reach(repo_get_merge_bases): pass on "missing commits" errors
  commit-reach(get_merge_bases_many_0): pass on "missing commits" errors
  commit-reach(merge_bases_many): pass on "missing commits" errors
  commit-reach(paint_down_to_common): start reporting errors
  commit-reach(paint_down_to_common): prepare for handling shallow commits
  commit-reach(repo_in_merge_bases_many): report missing commits
  commit-reach(repo_in_merge_bases_many): optionally expect missing commits
  commit-reach(paint_down_to_common): plug two memory leaks

bisect.c

@@ -836,10 +836,11 @@ static void handle_skipped_merge_base(const struct object_id *mb)
 static enum bisect_error check_merge_bases(int rev_nr, struct commit **rev, int no_checkout)
 {
 	enum bisect_error res = BISECT_OK;
-	struct commit_list *result;
+	struct commit_list *result = NULL;
 
-	result = repo_get_merge_bases_many(the_repository, rev[0], rev_nr - 1,
-					   rev + 1);
+	if (repo_get_merge_bases_many(the_repository, rev[0], rev_nr - 1,
+				      rev + 1, &result) < 0)
+		exit(128);
 
 	for (; result; result = result->next) {
 		const struct object_id *mb = &result->item->object.oid;

builtin/branch.c

@@ -158,6 +158,8 @@ static int branch_merged(int kind, const char *name,
 
 	merged = reference_rev ? repo_in_merge_bases(the_repository, rev,
 						     reference_rev) : 0;
+	if (merged < 0)
+		exit(128);
 
 	/*
 	 * After the safety valve is fully redefined to "check with
@@ -166,9 +168,13 @@ static int branch_merged(int kind, const char *name,
 	 * any of the following code, but during the transition period,
 	 * a gentle reminder is in order.
 	 */
-	if ((head_rev != reference_rev) &&
-	    (head_rev ? repo_in_merge_bases(the_repository, rev, head_rev) : 0) != merged) {
-		if (merged)
+	if (head_rev != reference_rev) {
+		int expect = head_rev ? repo_in_merge_bases(the_repository, rev, head_rev) : 0;
+		if (expect < 0)
+			exit(128);
+		if (expect == merged)
+			; /* okay */
+		else if (merged)
 			warning(_("deleting branch '%s' that has been merged to\n"
 				"         '%s', but not yet merged to HEAD"),
 				name, reference_name);

builtin/fast-import.c

@@ -1625,6 +1625,7 @@ static int update_branch(struct branch *b)
 		oidclr(&old_oid);
 	if (!force_update && !is_null_oid(&old_oid)) {
 		struct commit *old_cmit, *new_cmit;
+		int ret;
 
 		old_cmit = lookup_commit_reference_gently(the_repository,
 							  &old_oid, 0);
@@ -1633,7 +1634,10 @@ static int update_branch(struct branch *b)
 		if (!old_cmit || !new_cmit)
 			return error("Branch %s is missing commits.", b->name);
 
-		if (!repo_in_merge_bases(the_repository, old_cmit, new_cmit)) {
+		ret = repo_in_merge_bases(the_repository, old_cmit, new_cmit);
+		if (ret < 0)
+			exit(128);
+		if (!ret) {
 			warning("Not updating %s"
 				" (new tip %s does not contain %s)",
 				b->name, oid_to_hex(&b->oid),

builtin/fetch.c

@@ -981,6 +981,8 @@ static int update_local_ref(struct ref *ref,
 		uint64_t t_before = getnanotime();
 		fast_forward = repo_in_merge_bases(the_repository, current,
 						   updated);
+		if (fast_forward < 0)
+			exit(128);
 		forced_updates_ms += (getnanotime() - t_before) / 1000000;
 	} else {
 		fast_forward = 1;

builtin/log.c

@@ -1625,7 +1625,7 @@ static struct commit *get_base_commit(const char *base_commit,
 {
 	struct commit *base = NULL;
 	struct commit **rev;
-	int i = 0, rev_nr = 0, auto_select, die_on_failure;
+	int i = 0, rev_nr = 0, auto_select, die_on_failure, ret;
 
 	switch (auto_base) {
 	case AUTO_BASE_NEVER:
@@ -1658,7 +1658,7 @@ static struct commit *get_base_commit(const char *base_commit,
 		struct branch *curr_branch = branch_get(NULL);
 		const char *upstream = branch_get_upstream(curr_branch, NULL);
 		if (upstream) {
-			struct commit_list *base_list;
+			struct commit_list *base_list = NULL;
 			struct commit *commit;
 			struct object_id oid;
 
@@ -1669,11 +1669,12 @@ static struct commit *get_base_commit(const char *base_commit,
 					return NULL;
 			}
 			commit = lookup_commit_or_die(&oid, "upstream base");
-			base_list = repo_get_merge_bases_many(the_repository,
-							      commit, total,
-							      list);
-			/* There should be one and only one merge base. */
-			if (!base_list || base_list->next) {
+			if (repo_get_merge_bases_many(the_repository,
+						      commit, total,
+						      list,
+						      &base_list) < 0 ||
+			    /* There should be one and only one merge base. */
+			    !base_list || base_list->next) {
 				if (die_on_failure) {
 					die(_("could not find exact merge base"));
 				} else {
@@ -1704,11 +1705,11 @@ static struct commit *get_base_commit(const char *base_commit,
 	 */
 	while (rev_nr > 1) {
 		for (i = 0; i < rev_nr / 2; i++) {
-			struct commit_list *merge_base;
-			merge_base = repo_get_merge_bases(the_repository,
-							  rev[2 * i],
-							  rev[2 * i + 1]);
-			if (!merge_base || merge_base->next) {
+			struct commit_list *merge_base = NULL;
+			if (repo_get_merge_bases(the_repository,
+						 rev[2 * i],
+						 rev[2 * i + 1], &merge_base) < 0 ||
+			    !merge_base || merge_base->next) {
 				if (die_on_failure) {
 					die(_("failed to find exact merge base"));
 				} else {
@@ -1725,7 +1726,10 @@ static struct commit *get_base_commit(const char *base_commit,
 		rev_nr = DIV_ROUND_UP(rev_nr, 2);
 	}
 
-	if (!repo_in_merge_bases(the_repository, base, rev[0])) {
+	ret = repo_in_merge_bases(the_repository, base, rev[0]);
+	if (ret < 0)
+		exit(128);
+	if (!ret) {
 		if (die_on_failure) {
 			die(_("base commit should be the ancestor of revision list"));
 		} else {

builtin/merge-base.c

@@ -10,10 +10,13 @@
 
 static int show_merge_base(struct commit **rev, int rev_nr, int show_all)
 {
-	struct commit_list *result, *r;
+	struct commit_list *result = NULL, *r;
 
-	result = repo_get_merge_bases_many_dirty(the_repository, rev[0],
-						 rev_nr - 1, rev + 1);
+	if (repo_get_merge_bases_many_dirty(the_repository, rev[0],
+					    rev_nr - 1, rev + 1, &result) < 0) {
+		free_commit_list(result);
+		return -1;
+	}
 
 	if (!result)
 		return 1;
@@ -74,13 +77,17 @@ static int handle_independent(int count, const char **args)
 static int handle_octopus(int count, const char **args, int show_all)
 {
 	struct commit_list *revs = NULL;
-	struct commit_list *result, *rev;
+	struct commit_list *result = NULL, *rev;
 	int i;
 
 	for (i = count - 1; i >= 0; i--)
 		commit_list_insert(get_commit_reference(args[i]), &revs);
 
-	result = get_octopus_merge_bases(revs);
+	if (get_octopus_merge_bases(revs, &result) < 0) {
+		free_commit_list(revs);
+		free_commit_list(result);
+		return 128;
+	}
 	free_commit_list(revs);
 	reduce_heads_replace(&result);
 
@@ -100,12 +107,16 @@ static int handle_octopus(int count, const char **args, int show_all)
 static int handle_is_ancestor(int argc, const char **argv)
 {
 	struct commit *one, *two;
+	int ret;
 
 	if (argc != 2)
 		die("--is-ancestor takes exactly two commits");
 	one = get_commit_reference(argv[0]);
 	two = get_commit_reference(argv[1]);
-	if (repo_in_merge_bases(the_repository, one, two))
+	ret = repo_in_merge_bases(the_repository, one, two);
+	if (ret < 0)
+		exit(128);
+	if (ret)
 		return 0;
 	else
 		return 1;

builtin/merge-tree.c

@@ -476,8 +476,9 @@ static int real_merge(struct merge_tree_options *o,
 		 * Get the merge bases, in reverse order; see comment above
 		 * merge_incore_recursive in merge-ort.h
 		 */
-		merge_bases = repo_get_merge_bases(the_repository, parent1,
-						   parent2);
+		if (repo_get_merge_bases(the_repository, parent1,
+					 parent2, &merge_bases) < 0)
+			exit(128);
 		if (!merge_bases && !o->allow_unrelated_histories)
 			die(_("refusing to merge unrelated histories"));
 		merge_bases = reverse_commit_list(merge_bases);

builtin/merge.c

@@ -1513,13 +1513,20 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
 
 	if (!remoteheads)
 		; /* already up-to-date */
-	else if (!remoteheads->next)
-		common = repo_get_merge_bases(the_repository, head_commit,
-					      remoteheads->item);
-	else {
+	else if (!remoteheads->next) {
+		if (repo_get_merge_bases(the_repository, head_commit,
+					 remoteheads->item, &common) < 0) {
+			ret = 2;
+			goto done;
+		}
+	} else {
 		struct commit_list *list = remoteheads;
 		commit_list_insert(head_commit, &list);
-		common = get_octopus_merge_bases(list);
+		if (get_octopus_merge_bases(list, &common) < 0) {
+			free(list);
+			ret = 2;
+			goto done;
+		}
 		free(list);
 	}
 
@@ -1626,17 +1633,18 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
 		struct commit_list *j;
 
 		for (j = remoteheads; j; j = j->next) {
-			struct commit_list *common_one;
+			struct commit_list *common_one = NULL;
 			struct commit *common_item;
 
 			/*
 			 * Here we *have* to calculate the individual
 			 * merge_bases again, otherwise "git merge HEAD^
 			 * HEAD^^" would be missed.
 			 */
-			common_one = repo_get_merge_bases(the_repository,
-							  head_commit,
-							  j->item);
+			if (repo_get_merge_bases(the_repository, head_commit,
+						 j->item, &common_one) < 0)
+				exit(128);
+
 			common_item = common_one->item;
 			free_commit_list(common_one);
 			if (!oideq(&common_item->object.oid, &j->item->object.oid)) {

builtin/pull.c

@@ -815,7 +815,7 @@ static int get_octopus_merge_base(struct object_id *merge_base,
 		const struct object_id *merge_head,
 		const struct object_id *fork_point)
 {
-	struct commit_list *revs = NULL, *result;
+	struct commit_list *revs = NULL, *result = NULL;
 
 	commit_list_insert(lookup_commit_reference(the_repository, curr_head),
 			   &revs);
@@ -825,7 +825,8 @@ static int get_octopus_merge_base(struct object_id *merge_base,
 		commit_list_insert(lookup_commit_reference(the_repository, fork_point),
 				   &revs);
 
-	result = get_octopus_merge_bases(revs);
+	if (get_octopus_merge_bases(revs, &result) < 0)
+		exit(128);
 	free_commit_list(revs);
 	reduce_heads_replace(&result);
 
@@ -926,6 +927,8 @@ static int get_can_ff(struct object_id *orig_head,
 	merge_head = lookup_commit_reference(the_repository, orig_merge_head);
 	ret = repo_is_descendant_of(the_repository, merge_head, list);
 	free_commit_list(list);
+	if (ret < 0)
+		exit(128);
 	return ret;
 }
 
@@ -950,6 +953,8 @@ static int already_up_to_date(struct object_id *orig_head,
 		commit_list_insert(theirs, &list);
 		ok = repo_is_descendant_of(the_repository, ours, list);
 		free_commit_list(list);
+		if (ok < 0)
+			exit(128);
 		if (!ok)
 			return 0;
 	}

builtin/rebase.c

@@ -867,7 +867,8 @@ static int can_fast_forward(struct commit *onto, struct commit *upstream,
 	if (!upstream)
 		goto done;
 
-	merge_bases = repo_get_merge_bases(the_repository, upstream, head);
+	if (repo_get_merge_bases(the_repository, upstream, head, &merge_bases) < 0)
+		exit(128);
 	if (!merge_bases || merge_bases->next)
 		goto done;
 
@@ -886,8 +887,9 @@ static void fill_branch_base(struct rebase_options *options,
 {
 	struct commit_list *merge_bases = NULL;
 
-	merge_bases = repo_get_merge_bases(the_repository, options->onto,
-					   options->orig_head);
+	if (repo_get_merge_bases(the_repository, options->onto,
+				 options->orig_head, &merge_bases) < 0)
+		exit(128);
 	if (!merge_bases || merge_bases->next)
 		oidcpy(branch_base, null_oid());
 	else

builtin/receive-pack.c

@@ -1526,6 +1526,7 @@ static const char *update(struct command *cmd, struct shallow_info *si)
 	    starts_with(name, "refs/heads/")) {
 		struct object *old_object, *new_object;
 		struct commit *old_commit, *new_commit;
+		int ret2;
 
 		old_object = parse_object(the_repository, old_oid);
 		new_object = parse_object(the_repository, new_oid);
@@ -1539,7 +1540,10 @@ static const char *update(struct command *cmd, struct shallow_info *si)
 		}
 		old_commit = (struct commit *)old_object;
 		new_commit = (struct commit *)new_object;
-		if (!repo_in_merge_bases(the_repository, old_commit, new_commit)) {
+		ret2 = repo_in_merge_bases(the_repository, old_commit, new_commit);
+		if (ret2 < 0)
+			exit(128);
+		if (!ret2) {
 			rp_error("denying non-fast-forward %s"
 				 " (you should pull first)", name);
 			ret = "non-fast-forward";

builtin/rev-parse.c

@@ -297,15 +297,16 @@ static int try_difference(const char *arg)
 		show_rev(NORMAL, &end_oid, end);
 		show_rev(symmetric ? NORMAL : REVERSED, &start_oid, start);
 		if (symmetric) {
-			struct commit_list *exclude;
+			struct commit_list *exclude = NULL;
 			struct commit *a, *b;
 			a = lookup_commit_reference(the_repository, &start_oid);
 			b = lookup_commit_reference(the_repository, &end_oid);
 			if (!a || !b) {
 				*dotdot = '.';
 				return 0;
 			}
-			exclude = repo_get_merge_bases(the_repository, a, b);
+			if (repo_get_merge_bases(the_repository, a, b, &exclude) < 0)
+				exit(128);
 			while (exclude) {
 				struct commit *commit = pop_commit(&exclude);
 				show_rev(REVERSED, &commit->object.oid, NULL);