[PATCH v3 08/27] revisions API users: add "goto cleanup" for "rev_info" early exit

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

Add release_revisions() in various users of "struct rev_info" that can
mostly use a "goto cleanup" pattern, but also have an early "return"
before we've called repo_init_revisions(). We need to avoid calling
release_revisions() with uninitialized memory.

It would be a lot cleaner to be able to initialize "struct rev_info"
with "{ 0 }" here, or if a "REV_INFO_INIT" existed, we'll hopefully
get around to making the initialization easier in the future (now it
can't be done via a macro).

Until then let's leave a "cleanup_no_rev[s]" in place to document the
intention here. Only status_submodule() in builtin/submodule--helper.c
strictly speaking needs this, the other ones could keep their "return"
for the early exit. But let's have them also use the "goto
cleanup[...]" for consistency, and for the eventual migration to
simpler initialization.

For the bundle.c code see the early exit case added in
3bbbe467f29 (bundle verify: error out if called without an object
database, 2019-05-27).

For the relevant bisect.c code see 45b6370812c (bisect: libify
`check_good_are_ancestors_of_bad` and its dependents, 2020-02-17).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 bisect.c                    | 17 ++++++++++++-----
 builtin/submodule--helper.c |  6 ++++--
 bundle.c                    | 12 +++++++++---
 3 files changed, 25 insertions(+), 10 deletions(-)

diff --git a/bisect.c b/bisect.c
index cc6b8b6230d..c2e9f6ca9f6 100644
--- a/bisect.c
+++ b/bisect.c
@@ -1035,7 +1035,7 @@ enum bisect_error bisect_next_all(struct repository *r, const char *prefix)
 
 	res = check_good_are_ancestors_of_bad(r, prefix, no_checkout);
 	if (res)
-		return res;
+		goto cleanup_no_revs;
 
 	bisect_rev_setup(r, &revs, prefix, "%s", "^%s", 1);
 
@@ -1060,14 +1060,16 @@ enum bisect_error bisect_next_all(struct repository *r, const char *prefix)
 		       term_good,
 		       term_bad);
 
-		return BISECT_FAILED;
+		res = BISECT_FAILED;
+		goto cleanup;
 	}
 
 	if (!all) {
 		fprintf(stderr, _("No testable commit found.\n"
 			"Maybe you started with bad path arguments?\n"));
 
-		return BISECT_NO_TESTABLE_COMMIT;
+		res = BISECT_NO_TESTABLE_COMMIT;
+		goto cleanup;
 	}
 
 	bisect_rev = &revs.commits->item->object.oid;
@@ -1087,7 +1089,8 @@ enum bisect_error bisect_next_all(struct repository *r, const char *prefix)
 		 * for negative return values for early returns up
 		 * until the cmd_bisect__helper() caller.
 		 */
-		return BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND;
+		res = BISECT_INTERNAL_SUCCESS_1ST_BAD_FOUND;
+		goto cleanup;
 	}
 
 	nr = all - reaches - 1;
@@ -1106,7 +1109,11 @@ enum bisect_error bisect_next_all(struct repository *r, const char *prefix)
 	/* Clean up objects used, as they will be reused. */
 	repo_clear_commit_marks(r, ALL_REV_FLAGS);
 
-	return bisect_checkout(bisect_rev, no_checkout);
+	res = bisect_checkout(bisect_rev, no_checkout);
+cleanup:
+	release_revisions(&revs);
+cleanup_no_revs:
+	return res;
 }
 
 static inline int log2i(int n)
diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 24980863f68..d1b656c0909 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -779,7 +779,7 @@ static void status_submodule(const char *path, const struct object_id *ce_oid,
 
 	if ((CE_STAGEMASK & ce_flags) >> CE_STAGESHIFT) {
 		print_status(flags, 'U', path, null_oid(), displaypath);
-		goto cleanup;
+		goto cleanup_no_rev;
 	}
 
 	strbuf_addf(&buf, "%s/.git", path);
@@ -791,7 +791,7 @@ static void status_submodule(const char *path, const struct object_id *ce_oid,
 	    !is_git_directory(git_dir)) {
 		print_status(flags, '-', path, ce_oid, displaypath);
 		strbuf_release(&buf);
-		goto cleanup;
+		goto cleanup_no_rev;
 	}
 	strbuf_release(&buf);
 
@@ -851,6 +851,8 @@ static void status_submodule(const char *path, const struct object_id *ce_oid,
 	}
 
 cleanup:
+	release_revisions(&rev);
+cleanup_no_rev:
 	strvec_clear(&diff_files_args);
 	free(displaypath);
 }
diff --git a/bundle.c b/bundle.c
index e359370cfcd..9b7c0bc55c4 100644
--- a/bundle.c
+++ b/bundle.c
@@ -202,8 +202,10 @@ int verify_bundle(struct repository *r,
 	int i, ret = 0, req_nr;
 	const char *message = _("Repository lacks these prerequisite commits:");
 
-	if (!r || !r->objects || !r->objects->odb)
-		return error(_("need a repository to verify a bundle"));
+	if (!r || !r->objects || !r->objects->odb) {
+		ret = error(_("need a repository to verify a bundle"));
+		goto cleanup_no_revs;
+	}
 
 	repo_init_revisions(r, &revs, NULL);
 	for (i = 0; i < p->nr; i++) {
@@ -221,7 +223,7 @@ int verify_bundle(struct repository *r,
 		error("%s %s", oid_to_hex(oid), name);
 	}
 	if (revs.pending.nr != p->nr)
-		return ret;
+		goto cleanup;
 	req_nr = revs.pending.nr;
 	setup_revisions(2, argv, &revs, NULL);
 
@@ -283,6 +285,10 @@ int verify_bundle(struct repository *r,
 			list_refs(r, 0, NULL);
 		}
 	}
+
+cleanup:
+	release_revisions(&revs);
+cleanup_no_revs:
 	return ret;
 }
 
-- 
2.35.1.1509.ge4eeb5bd39e