NULL_SHA1 is never a valid value for a reference. If a loose reference
has that value, mark it as broken.
Why check NULL_SHA1 and not the nearly 2^160 other SHA-1s that are
also invalid in a given repository? Because (a) it is cheap to test
for NULL_SHA1, and (b) NULL_SHA1 is often used as a "SHA-1 is invalid"
value inside of Git client source code (not only ours!), and
accidentally writing it to a loose reference file would be an easy
mistake to make.
Signed-off-by: Michael Haggerty <mhagger@xxxxxxxxxxxx>
---
refs.c | 7 +++++++
t/t6301-for-each-ref-errors.sh | 2 +-
2 files changed, 8 insertions(+), 1 deletion(-)
diff --git a/refs.c b/refs.c
index 47e4e53..c28fde1 100644
--- a/refs.c
+++ b/refs.c
@@ -1321,6 +1321,13 @@ static void read_loose_refs(const char *dirname, struct ref_dir *dir)
hashclr(sha1);
flag |= REF_ISBROKEN;
}
+
+ if (!(flag & REF_ISBROKEN) && is_null_sha1(sha1)) {
+ /* NULL_SHA1 is never a valid reference value. */
+ hashclr(sha1);
+ flag |= REF_ISBROKEN;
+ }
+
if (check_refname_format(refname.buf,
REFNAME_ALLOW_ONELEVEL)) {
hashclr(sha1);
diff --git a/t/t6301-for-each-ref-errors.sh b/t/t6301-for-each-ref-errors.sh
index b9af9a9..f737cce 100755
--- a/t/t6301-for-each-ref-errors.sh
+++ b/t/t6301-for-each-ref-errors.sh
@@ -23,7 +23,7 @@ test_expect_success 'Broken refs are reported correctly' '
test_cmp broken-err err
'
-test_expect_failure 'NULL_SHA1 refs are reported correctly' '
+test_expect_success 'NULL_SHA1 refs are reported correctly' '
r=refs/heads/zeros &&
echo $ZEROS >.git/$r &&
test_when_finished "rm -f .git/$r" &&
--
2.1.4
--
To unsubscribe from this list: send the line "unsubscribe git" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html