From: Han-Wen Nienhuys <hanwen@xxxxxxxxxx>
When writing the same hash many times, we might decide to use a
length-1 object ID prefix for the ObjectID => ref table, which is out
of spec.
Signed-off-by: Han-Wen Nienhuys <hanwen@xxxxxxxxxx>
---
reftable/readwrite_test.c | 37 +++++++++++++++++++++++++++++++++++++
reftable/writer.c | 4 +++-
2 files changed, 40 insertions(+), 1 deletion(-)
diff --git a/reftable/readwrite_test.c b/reftable/readwrite_test.c
index fd5922e55f6..35142eb070e 100644
--- a/reftable/readwrite_test.c
+++ b/reftable/readwrite_test.c
@@ -667,6 +667,42 @@ static void test_write_empty_table(void)
strbuf_release(&buf);
}
+static void test_write_object_id_min_length(void)
+{
+ struct reftable_write_options opts = {
+ .block_size = 75,
+ };
+ struct strbuf buf = STRBUF_INIT;
+ struct reftable_writer *w =
+ reftable_new_writer(&strbuf_add_void, &buf, &opts);
+ uint8_t hash[GIT_SHA1_RAWSZ] = {42};
+ struct reftable_ref_record ref = {
+ .update_index = 1,
+ .value_type = REFTABLE_REF_VAL1,
+ .value.val1 = hash,
+ };
+ int err;
+ int i;
+
+ reftable_writer_set_limits(w, 1, 1);
+
+ /* Write the same hash in many refs. If there is only 1 hash, the
+ * disambiguating prefix is length 0 */
+ for (i = 0; i < 256; i++) {
+ char name[256];
+ snprintf(name, sizeof(name), "ref%05d", i);
+ ref.refname = name;
+ err = reftable_writer_add_ref(w, &ref);
+ EXPECT_ERR(err);
+ }
+
+ err = reftable_writer_close(w);
+ EXPECT_ERR(err);
+ EXPECT(writer_stats(w)->object_id_len == 2);
+ reftable_writer_free(w);
+ strbuf_release(&buf);
+}
+
static void test_write_empty_key(void)
{
struct reftable_write_options opts = { 0 };
@@ -772,5 +808,6 @@ int readwrite_test_main(int argc, const char *argv[])
RUN_TEST(test_write_empty_key);
RUN_TEST(test_write_empty_table);
RUN_TEST(test_log_overflow);
+ RUN_TEST(test_write_object_id_min_length);
return 0;
}
diff --git a/reftable/writer.c b/reftable/writer.c
index d54215a50dc..5e4e6e93416 100644
--- a/reftable/writer.c
+++ b/reftable/writer.c
@@ -515,7 +515,9 @@ static void object_record_free(void *void_arg, void *key)
static int writer_dump_object_index(struct reftable_writer *w)
{
struct write_record_arg closure = { .w = w };
- struct common_prefix_arg common = { NULL };
+ struct common_prefix_arg common = {
+ .max = 1, /* obj_id_len should be >= 2. */
+ };
if (w->obj_index_tree) {
infix_walk(w->obj_index_tree, &update_common, &common);
}
--
gitgitgadget
