refs: propagate errno when reading special refs fails
Some refs in Git are more special than others due to reasons explained in the next commit. These refs are read via `refs_read_special_head()`, but this function doesn't behave the same as when we try to read a normal ref. Most importantly, we do not propagate `failure_errno` in the case where the reference does not exist, which is behaviour that we rely on in many parts of Git. Fix this bug by propagating errno when `strbuf_read_file()` fails. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Patrick Steinhardt committed
Dec 14, 2023 at 14:37 UTC
668cdc043fe6f6d1fa2bf2b3f3c2375a20819e77
2 files changed
+13
-1
refs.c
+3
-1
@@ -1806,8 +1806,10 @@ static int refs_read_special_head(struct ref_store *ref_store,
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int result = -1;
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strbuf_addf(&full_path, "%s/%s", ref_store->gitdir, refname);
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- if (strbuf_read_file(&content, full_path.buf, 0) < 0)
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+ if (strbuf_read_file(&content, full_path.buf, 0) < 0) {
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+ *failure_errno = errno;
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goto done;
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+ }
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result = parse_loose_ref_contents(content.buf, oid, referent, type,
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failure_errno);
t/t1403-show-ref.sh
+10
@@ -266,4 +266,14 @@ test_expect_success '--exists with directory fails with generic error' '
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test_cmp expect err
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'
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+test_expect_success '--exists with non-existent special ref' '
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+ test_expect_code 2 git show-ref --exists FETCH_HEAD
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+'
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+
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+test_expect_success '--exists with existing special ref' '
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+ test_when_finished "rm .git/FETCH_HEAD" &&
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+ git rev-parse HEAD >.git/FETCH_HEAD &&
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+ git show-ref --exists FETCH_HEAD
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+'
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+
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test_done