commit-graph: verify required chunks are present

The commit-graph file requires the following three chunks:

* OID Fanout
* OID Lookup
* Commit Data

If any of these are missing, then the 'verify' subcommand should
report a failure. This includes the chunk IDs malformed or the
chunk count is truncated.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/commit-graph.c b/commit-graph.c
index 488216a736c272292641323d10681c6eece1ea3f..26328c3b74a0dc128514817d5387fc4e02cefaca 100644 (file)
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -848,5 +848,14 @@ int verify_commit_graph(struct repository *r, struct commit_graph *g)
                return 1;
        }
 
+       verify_commit_graph_error = 0;
+
+       if (!g->chunk_oid_fanout)
+               graph_report("commit-graph is missing the OID Fanout chunk");
+       if (!g->chunk_oid_lookup)
+               graph_report("commit-graph is missing the OID Lookup chunk");
+       if (!g->chunk_commit_data)
+               graph_report("commit-graph is missing the Commit Data chunk");
+
        return verify_commit_graph_error;
 }

diff --git a/t/t5318-commit-graph.sh b/t/t5318-commit-graph.sh
index c0c1ff09b904386f8c8a3b2f6db3c6c7dcf7be63..dc16849ddd5530287768123391e0d3e692489ad8 100755 (executable)
--- a/t/t5318-commit-graph.sh
+++ b/t/t5318-commit-graph.sh
@@ -249,6 +249,15 @@ test_expect_success 'git commit-graph verify' '
 
 GRAPH_BYTE_VERSION=4
 GRAPH_BYTE_HASH=5
+GRAPH_BYTE_CHUNK_COUNT=6
+GRAPH_CHUNK_LOOKUP_OFFSET=8
+GRAPH_CHUNK_LOOKUP_WIDTH=12
+GRAPH_CHUNK_LOOKUP_ROWS=5
+GRAPH_BYTE_OID_FANOUT_ID=$GRAPH_CHUNK_LOOKUP_OFFSET
+GRAPH_BYTE_OID_LOOKUP_ID=$(($GRAPH_CHUNK_LOOKUP_OFFSET + \
+                           1 * $GRAPH_CHUNK_LOOKUP_WIDTH))
+GRAPH_BYTE_COMMIT_DATA_ID=$(($GRAPH_CHUNK_LOOKUP_OFFSET + \
+                            2 * $GRAPH_CHUNK_LOOKUP_WIDTH))
 
 # usage: corrupt_graph_and_verify <position> <data> <string>
 # Manipulates the commit-graph file at the position
@@ -283,4 +292,24 @@ test_expect_success 'detect bad hash version' '
                "hash version"
 '
 
+test_expect_success 'detect low chunk count' '
+       corrupt_graph_and_verify $GRAPH_BYTE_CHUNK_COUNT "\02" \
+               "missing the .* chunk"
+'
+
+test_expect_success 'detect missing OID fanout chunk' '
+       corrupt_graph_and_verify $GRAPH_BYTE_OID_FANOUT_ID "\0" \
+               "missing the OID Fanout chunk"
+'
+
+test_expect_success 'detect missing OID lookup chunk' '
+       corrupt_graph_and_verify $GRAPH_BYTE_OID_LOOKUP_ID "\0" \
+               "missing the OID Lookup chunk"
+'
+
+test_expect_success 'detect missing commit data chunk' '
+       corrupt_graph_and_verify $GRAPH_BYTE_COMMIT_DATA_ID "\0" \
+               "missing the Commit Data chunk"
+'
+
 test_done