reftable/writer: refactorings for writer_add_record()

Large parts of the reftable library do not conform to Git's typical code
style. Refactor `writer_add_record()` such that it conforms better to it
and add some documentation that explains some of its more intricate
behaviour.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Patrick Steinhardt
2024-04-08 14:24:16 +02:00
committed by Junio C Hamano
parent 44afd85fbd
commit d0dd119f72

View File

@ -209,7 +209,8 @@ static int writer_add_record(struct reftable_writer *w,
struct reftable_record *rec)
{
struct strbuf key = STRBUF_INIT;
int err = -1;
int err;
reftable_record_key(rec, &key);
if (strbuf_cmp(&w->last_key, &key) >= 0) {
err = REFTABLE_API_ERROR;
@ -218,27 +219,42 @@ static int writer_add_record(struct reftable_writer *w,
strbuf_reset(&w->last_key);
strbuf_addbuf(&w->last_key, &key);
if (!w->block_writer) {
if (!w->block_writer)
writer_reinit_block_writer(w, reftable_record_type(rec));
}
assert(block_writer_type(w->block_writer) == reftable_record_type(rec));
if (block_writer_type(w->block_writer) != reftable_record_type(rec))
BUG("record of type %d added to writer of type %d",
reftable_record_type(rec), block_writer_type(w->block_writer));
if (block_writer_add(w->block_writer, rec) == 0) {
/*
* Try to add the record to the writer. If this succeeds then we're
* done. Otherwise the block writer may have hit the block size limit
* and needs to be flushed.
*/
if (!block_writer_add(w->block_writer, rec)) {
err = 0;
goto done;
}
/*
* The current block is full, so we need to flush and reinitialize the
* writer to start writing the next block.
*/
err = writer_flush_block(w);
if (err < 0) {
if (err < 0)
goto done;
}
writer_reinit_block_writer(w, reftable_record_type(rec));
/*
* Try to add the record to the writer again. If this still fails then
* the record does not fit into the block size.
*
* TODO: it would be great to have `block_writer_add()` return proper
* error codes so that we don't have to second-guess the failure
* mode here.
*/
err = block_writer_add(w->block_writer, rec);
if (err == -1) {
/* we are writing into memory, so an error can only mean it
* doesn't fit. */
if (err) {
err = REFTABLE_ENTRY_TOO_BIG_ERROR;
goto done;
}