oidtree: extend iteration to allow for arbitrary return codes

The interface `cb_each()` iterates through a crit-bit tree and calls a
specific callback function for each of the contained items. The callback
function is expected to return either:

  - `CB_CONTINUE` in case iteration shall continue.

  - `CB_BREAK` to abort iteration.

This is needlessly restrictive though, as callers may want to return
arbitrary values and have them be bubbled up to the `cb_each()` call
site. In fact, this is a rather common pattern we have: whenever such a
callback function returns a non-zero error code, we abort iteration and
bubble up the code as-is.

Refactor both the crit-bit tree and oidtree subsystems to behave
accordingly.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/t/unit-tests/u-oidtree.c b/t/unit-tests/u-oidtree.c
index def47c6795..d4d05c7dc3 100644
--- a/t/unit-tests/u-oidtree.c
+++ b/t/unit-tests/u-oidtree.c
@@ -38,7 +38,7 @@ struct expected_hex_iter {
 	const char *query;
 };
 
-static enum cb_next check_each_cb(const struct object_id *oid, void *data)
+static int check_each_cb(const struct object_id *oid, void *data)
 {
 	struct expected_hex_iter *hex_iter = data;
 	struct object_id expected;
@@ -49,7 +49,7 @@ static enum cb_next check_each_cb(const struct object_id *oid, void *data)
 			 &expected);
 	cl_assert_equal_s(oid_to_hex(oid), oid_to_hex(&expected));
 	hex_iter->i += 1;
-	return CB_CONTINUE;
+	return 0;
 }
 
 LAST_ARG_MUST_BE_NULL