reftable/reader: unify indexed and linear seeking
In `reader_seek_internal()` we either end up doing an indexed seek when there is one or a linear seek otherwise. These two code paths are disjunct without a good reason, where the indexed seek will cause us to exit early. Refactor the two code paths such that it becomes possible to share a bit more code between them. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Patrick Steinhardt committed
May 13, 2024 at 10:47 UTC
dfdd1455bbb2eed6674964000d037cd213687a33
1 file changed
+16
-26
reftable/reader.c
+16
-26
@@ -425,7 +425,7 @@ static int reader_seek_linear(struct table_iter *ti,
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struct strbuf want_key = STRBUF_INIT;
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struct strbuf got_key = STRBUF_INIT;
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struct reftable_record rec;
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- int err = -1;
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+ int err;
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reftable_record_init(&rec, reftable_record_type(want));
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reftable_record_key(want, &want_key);
@@ -499,8 +499,8 @@ done:
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return err;
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}
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-static int reader_seek_indexed(struct reftable_reader *r,
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- struct reftable_iterator *it,
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+static int reader_seek_indexed(struct table_iter *ti,
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+ struct reftable_reader *r,
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struct reftable_record *rec)
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{
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struct reftable_record want_index = {
@@ -510,13 +510,9 @@ static int reader_seek_indexed(struct reftable_reader *r,
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.type = BLOCK_TYPE_INDEX,
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.u.idx = { .last_key = STRBUF_INIT },
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};
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- struct table_iter ti = TABLE_ITER_INIT, *malloced;
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- int err = 0;
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+ int err;
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reftable_record_key(rec, &want_index.u.idx.last_key);
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- err = reader_start(r, &ti, reftable_record_type(rec), 1);
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- if (err < 0)
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- goto done;
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/*
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* The index may consist of multiple levels, where each level may have
@@ -524,7 +520,7 @@ static int reader_seek_indexed(struct reftable_reader *r,
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* highest layer that identifies the relevant index block as well as
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* the record inside that block that corresponds to our wanted key.
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*/
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- err = reader_seek_linear(&ti, &want_index);
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+ err = reader_seek_linear(ti, &want_index);
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if (err < 0)
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goto done;
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@@ -550,36 +546,30 @@ static int reader_seek_indexed(struct reftable_reader *r,
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* all levels of the index only to find out that the key does
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* not exist.
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*/
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- err = table_iter_next(&ti, &index_result);
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+ err = table_iter_next(ti, &index_result);
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if (err != 0)
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goto done;
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- err = reader_table_iter_at(r, &ti, index_result.u.idx.offset, 0);
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+ err = reader_table_iter_at(r, ti, index_result.u.idx.offset, 0);
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if (err != 0)
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goto done;
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- err = block_iter_seek_key(&ti.bi, &ti.br, &want_index.u.idx.last_key);
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+ err = block_iter_seek_key(&ti->bi, &ti->br, &want_index.u.idx.last_key);
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if (err < 0)
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goto done;
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- if (ti.typ == reftable_record_type(rec)) {
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+ if (ti->typ == reftable_record_type(rec)) {
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err = 0;
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break;
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}
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- if (ti.typ != BLOCK_TYPE_INDEX) {
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+ if (ti->typ != BLOCK_TYPE_INDEX) {
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err = REFTABLE_FORMAT_ERROR;
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goto done;
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}
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}
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- REFTABLE_ALLOC_ARRAY(malloced, 1);
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- *malloced = ti;
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- iterator_from_table_iter(it, malloced);
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-
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done:
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- if (err)
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- table_iter_close(&ti);
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reftable_record_release(&want_index);
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reftable_record_release(&index_result);
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return err;
@@ -595,15 +585,15 @@ static int reader_seek_internal(struct reftable_reader *r,
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struct table_iter ti = TABLE_ITER_INIT, *p;
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int err;
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- if (idx > 0)
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- return reader_seek_indexed(r, it, rec);
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-
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- err = reader_start(r, &ti, reftable_record_type(rec), 0);
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+ err = reader_start(r, &ti, reftable_record_type(rec), !!idx);
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if (err < 0)
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goto out;
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- err = reader_seek_linear(&ti, rec);
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- if (err < 0)
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+ if (idx)
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+ err = reader_seek_indexed(&ti, r, rec);
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+ else
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+ err = reader_seek_linear(&ti, rec);
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+ if (err)
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goto out;
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REFTABLE_ALLOC_ARRAY(p, 1);