When validating that a commit-graph has either all zero, or all non-zero
generation numbers, we emit a warning on both the rising and falling
edge of transitioning between the two.
So if we are unfortunate enough to see a commit-graph which has a
repeating sequence of zero, then non-zero generation numbers, we'll
generate many warnings that contain more or less the same information.
Avoid this by treating `generation_zero` as a bit-field, and warn under
the same conditions, but only do so once.
Suggested-by: Junio C Hamano <gitster@xxxxxxxxx>
Signed-off-by: Taylor Blau <me@xxxxxxxxxxxx>
---
commit-graph.c | 17 ++++++++++-------
t/t5318-commit-graph.sh | 14 ++++++++++++++
2 files changed, 24 insertions(+), 7 deletions(-)
diff --git a/commit-graph.c b/commit-graph.c
index f7d9b31546..8d924b4509 100644
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -2562,6 +2562,8 @@ static void graph_report(const char *fmt, ...)
#define GENERATION_ZERO_EXISTS 1
#define GENERATION_NUMBER_EXISTS 2
+#define GENERATION_NUMBER_BOTH_EXIST \
+ (GENERATION_ZERO_EXISTS | GENERATION_NUMBER_EXISTS)
static int commit_graph_checksum_valid(struct commit_graph *g)
{
@@ -2573,19 +2575,19 @@ static void verify_mixed_generation_numbers(struct commit_graph *g,
int *generation_zero)
{
if (commit_graph_generation_from_graph(graph_commit)) {
- if (*generation_zero == GENERATION_ZERO_EXISTS)
+ if (*generation_zero & GENERATION_ZERO_EXISTS)
graph_report(_("commit-graph has non-zero generation "
"number for commit %s, but zero "
"elsewhere"),
oid_to_hex(&graph_commit->object.oid));
- *generation_zero = GENERATION_NUMBER_EXISTS;
+ *generation_zero |= GENERATION_NUMBER_EXISTS;
} else {
- if (*generation_zero == GENERATION_NUMBER_EXISTS)
+ if (*generation_zero & GENERATION_NUMBER_EXISTS)
graph_report(_("commit-graph has generation number "
"zero for commit %s, but non-zero "
"elsewhere"),
oid_to_hex(&graph_commit->object.oid));
- *generation_zero = GENERATION_ZERO_EXISTS;
+ *generation_zero |= GENERATION_ZERO_EXISTS;
}
}
@@ -2702,10 +2704,11 @@ static int verify_one_commit_graph(struct repository *r,
graph_report(_("commit-graph parent list for commit %s terminates early"),
oid_to_hex(&cur_oid));
- verify_mixed_generation_numbers(g, graph_commit,
- &generation_zero);
+ if (generation_zero != GENERATION_NUMBER_BOTH_EXIST)
+ verify_mixed_generation_numbers(g, graph_commit,
+ &generation_zero);
- if (generation_zero == GENERATION_ZERO_EXISTS)
+ if (generation_zero & GENERATION_ZERO_EXISTS)
continue;
/*
diff --git a/t/t5318-commit-graph.sh b/t/t5318-commit-graph.sh
index 8e96471b34..2626d41c94 100755
--- a/t/t5318-commit-graph.sh
+++ b/t/t5318-commit-graph.sh
@@ -628,6 +628,20 @@ test_expect_success 'detect mixed generation numbers (zero to non-zero)' '
"but zero elsewhere"
'
+test_expect_success 'detect mixed generation numbers (flip-flop)' '
+ corrupt_graph_setup &&
+ for pos in \
+ $GRAPH_BYTE_COMMIT_GENERATION \
+ $GRAPH_BYTE_COMMIT_GENERATION_LAST
+ do
+ printf "\0\0\0\0" | dd of="full/$objdir/info/commit-graph" bs=1 \
+ seek="$pos" conv=notrunc || return 1
+ done &&
+
+ test_must_fail git -C full commit-graph verify 2>err &&
+ test 1 -eq "$(grep -c "generation number" err)"
+'
+
test_expect_success 'git fsck (checks commit-graph when config set to true)' '
git -C full fsck &&
corrupt_graph_and_verify $GRAPH_BYTE_FOOTER "\00" \
--
2.42.0.rc0.30.gb82b15ebc8
