Merge branch 'ps/reftable-multi-level-indices-fix'

Write multi-level indices for reftable has been corrected.

* ps/reftable-multi-level-indices-fix:
  reftable: document reading and writing indices
  reftable/writer: fix writing multi-level indices
  reftable/writer: simplify writing index records
  reftable/writer: use correct type to iterate through index entries
  reftable/reader: be more careful about errors in indexed seeks

1 files changed, 56 insertions, 0 deletions

diff --git a/reftable/readwrite_test.c b/reftable/readwrite_test.c
index 6b99daeaf2..853923397e 100644
--- a/reftable/readwrite_test.c
+++ b/reftable/readwrite_test.c
@@ -866,6 +866,61 @@ static void test_write_multiple_indices(void)
 	strbuf_release(&buf);
 }
 
+static void test_write_multi_level_index(void)
+{
+	struct reftable_write_options opts = {
+		.block_size = 100,
+	};
+	struct strbuf writer_buf = STRBUF_INIT, buf = STRBUF_INIT;
+	struct reftable_block_source source = { 0 };
+	struct reftable_iterator it = { 0 };
+	const struct reftable_stats *stats;
+	struct reftable_writer *writer;
+	struct reftable_reader *reader;
+	int err;
+
+	writer = reftable_new_writer(&strbuf_add_void, &noop_flush, &writer_buf, &opts);
+	reftable_writer_set_limits(writer, 1, 1);
+	for (size_t i = 0; i < 200; i++) {
+		struct reftable_ref_record ref = {
+			.update_index = 1,
+			.value_type = REFTABLE_REF_VAL1,
+			.value.val1 = {i},
+		};
+
+		strbuf_reset(&buf);
+		strbuf_addf(&buf, "refs/heads/%03" PRIuMAX, (uintmax_t)i);
+		ref.refname = buf.buf,
+
+		err = reftable_writer_add_ref(writer, &ref);
+		EXPECT_ERR(err);
+	}
+	reftable_writer_close(writer);
+
+	/*
+	 * The written refs should be sufficiently large to result in a
+	 * multi-level index.
+	 */
+	stats = reftable_writer_stats(writer);
+	EXPECT(stats->ref_stats.max_index_level == 2);
+
+	block_source_from_strbuf(&source, &writer_buf);
+	err = reftable_new_reader(&reader, &source, "filename");
+	EXPECT_ERR(err);
+
+	/*
+	 * Seeking the last ref should work as expected.
+	 */
+	err = reftable_reader_seek_ref(reader, &it, "refs/heads/199");
+	EXPECT_ERR(err);
+
+	reftable_iterator_destroy(&it);
+	reftable_writer_free(writer);
+	reftable_reader_free(reader);
+	strbuf_release(&writer_buf);
+	strbuf_release(&buf);
+}
+
 static void test_corrupt_table_empty(void)
 {
 	struct strbuf buf = STRBUF_INIT;
@@ -916,5 +971,6 @@ int readwrite_test_main(int argc, const char *argv[])
 	RUN_TEST(test_write_object_id_length);
 	RUN_TEST(test_write_object_id_min_length);
 	RUN_TEST(test_write_multiple_indices);
+	RUN_TEST(test_write_multi_level_index);
 	return 0;
 }