reftable/block: make block iterators reseekable

Refactor the block iterators so that initialization and seeking are
different from one another. This makes the iterator trivially reseekable
by storing the pointer to the block at initialization time, which we can
then reuse on every seek.

This refactoring prepares the code for exposing a `reftable_iterator`
interface for blocks in a subsequent commit. Callsites are adjusted
accordingly.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 11 insertions, 15 deletions

diff --git a/t/unit-tests/t-reftable-block.c b/t/unit-tests/t-reftable-block.c
index e36ed7ac57..9f91d697f6 100644
--- a/t/unit-tests/t-reftable-block.c
+++ b/t/unit-tests/t-reftable-block.c
@@ -66,7 +66,7 @@ static void t_ref_block_read_write(void)
 	block_source_from_buf(&source ,&block_data);
 	reftable_block_init(&block, &source, 0, header_off, block_size, REFTABLE_HASH_SIZE_SHA1);
 
-	block_iter_seek_start(&it, &block);
+	block_iter_init(&it, &block);
 
 	for (i = 0; ; i++) {
 		ret = block_iter_next(&it, &rec);
@@ -79,10 +79,9 @@ static void t_ref_block_read_write(void)
 	}
 
 	for (i = 0; i < N; i++) {
-		block_iter_reset(&it);
 		reftable_record_key(&recs[i], &want);
 
-		ret = block_iter_seek_key(&it, &block, &want);
+		ret = block_iter_seek_key(&it, &want);
 		check_int(ret, ==, 0);
 
 		ret = block_iter_next(&it, &rec);
@@ -91,7 +90,7 @@ static void t_ref_block_read_write(void)
 		check(reftable_record_equal(&recs[i], &rec, REFTABLE_HASH_SIZE_SHA1));
 
 		want.len--;
-		ret = block_iter_seek_key(&it, &block, &want);
+		ret = block_iter_seek_key(&it, &want);
 		check_int(ret, ==, 0);
 
 		ret = block_iter_next(&it, &rec);
@@ -156,7 +155,7 @@ static void t_log_block_read_write(void)
 	block_source_from_buf(&source, &block_data);
 	reftable_block_init(&block, &source, 0, header_off, block_size, REFTABLE_HASH_SIZE_SHA1);
 
-	block_iter_seek_start(&it, &block);
+	block_iter_init(&it, &block);
 
 	for (i = 0; ; i++) {
 		ret = block_iter_next(&it, &rec);
@@ -169,11 +168,10 @@ static void t_log_block_read_write(void)
 	}
 
 	for (i = 0; i < N; i++) {
-		block_iter_reset(&it);
 		reftable_buf_reset(&want);
 		check(!reftable_buf_addstr(&want, recs[i].u.log.refname));
 
-		ret = block_iter_seek_key(&it, &block, &want);
+		ret = block_iter_seek_key(&it, &want);
 		check_int(ret, ==, 0);
 
 		ret = block_iter_next(&it, &rec);
@@ -182,7 +180,7 @@ static void t_log_block_read_write(void)
 		check(reftable_record_equal(&recs[i], &rec, REFTABLE_HASH_SIZE_SHA1));
 
 		want.len--;
-		ret = block_iter_seek_key(&it, &block, &want);
+		ret = block_iter_seek_key(&it, &want);
 		check_int(ret, ==, 0);
 
 		ret = block_iter_next(&it, &rec);
@@ -249,7 +247,7 @@ static void t_obj_block_read_write(void)
 	block_source_from_buf(&source, &block_data);
 	reftable_block_init(&block, &source, 0, header_off, block_size, REFTABLE_HASH_SIZE_SHA1);
 
-	block_iter_seek_start(&it, &block);
+	block_iter_init(&it, &block);
 
 	for (i = 0; ; i++) {
 		ret = block_iter_next(&it, &rec);
@@ -262,10 +260,9 @@ static void t_obj_block_read_write(void)
 	}
 
 	for (i = 0; i < N; i++) {
-		block_iter_reset(&it);
 		reftable_record_key(&recs[i], &want);
 
-		ret = block_iter_seek_key(&it, &block, &want);
+		ret = block_iter_seek_key(&it, &want);
 		check_int(ret, ==, 0);
 
 		ret = block_iter_next(&it, &rec);
@@ -334,7 +331,7 @@ static void t_index_block_read_write(void)
 	block_source_from_buf(&source, &block_data);
 	reftable_block_init(&block, &source, 0, header_off, block_size, REFTABLE_HASH_SIZE_SHA1);
 
-	block_iter_seek_start(&it, &block);
+	block_iter_init(&it, &block);
 
 	for (i = 0; ; i++) {
 		ret = block_iter_next(&it, &rec);
@@ -347,10 +344,9 @@ static void t_index_block_read_write(void)
 	}
 
 	for (i = 0; i < N; i++) {
-		block_iter_reset(&it);
 		reftable_record_key(&recs[i], &want);
 
-		ret = block_iter_seek_key(&it, &block, &want);
+		ret = block_iter_seek_key(&it, &want);
 		check_int(ret, ==, 0);
 
 		ret = block_iter_next(&it, &rec);
@@ -359,7 +355,7 @@ static void t_index_block_read_write(void)
 		check(reftable_record_equal(&recs[i], &rec, REFTABLE_HASH_SIZE_SHA1));
 
 		want.len--;
-		ret = block_iter_seek_key(&it, &block, &want);
+		ret = block_iter_seek_key(&it, &want);
 		check_int(ret, ==, 0);
 
 		ret = block_iter_next(&it, &rec);