reftable/reader: set up the reader when initializing table iterator

All the seeking functions accept a `struct reftable_reader` as input
such that they can use the reader to look up the respective blocks.
Refactor the code to instead set up the reader as a member of `struct
table_iter` during initialization such that we don't have to pass the
reader on every single call.

This step is required to move seeking of records into the generic
`struct reftable_iterator` infrastructure.

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

diff --git a/reftable/reader.c b/reftable/reader.c
index c3541e2c43c99dcb1f265808acb71479c31f0d1d..021608f6383ac2f672341ae54396ea325ae32e9c 100644 (file)
--- a/reftable/reader.c
+++ b/reftable/reader.c
@@ -224,8 +224,14 @@ struct table_iter {
        struct block_iter bi;
        int is_finished;
 };
-#define TABLE_ITER_INIT { \
-       .bi = BLOCK_ITER_INIT \
+
+static int table_iter_init(struct table_iter *ti, struct reftable_reader *r)
+{
+       struct block_iter bi = BLOCK_ITER_INIT;
+       memset(ti, 0, sizeof(*ti));
+       ti->r = r;
+       ti->bi = bi;
+       return 0;
 }
 
 static int table_iter_next_in_block(struct table_iter *ti,
@@ -386,26 +392,23 @@ static void iterator_from_table_iter(struct reftable_iterator *it,
        it->ops = &table_iter_vtable;
 }
 
-static int table_iter_seek_to(struct table_iter *ti, struct reftable_reader *r,
-                             uint64_t off, uint8_t typ)
+static int table_iter_seek_to(struct table_iter *ti, uint64_t off, uint8_t typ)
 {
        int err;
 
-       err = reader_init_block_reader(r, &ti->br, off, typ);
+       err = reader_init_block_reader(ti->r, &ti->br, off, typ);
        if (err != 0)
                return err;
 
-       ti->r = r;
        ti->typ = block_reader_type(&ti->br);
        ti->block_off = off;
        block_iter_seek_start(&ti->bi, &ti->br);
        return 0;
 }
 
-static int table_iter_seek_start(struct table_iter *ti, struct reftable_reader *r,
-                                uint8_t typ, int index)
+static int table_iter_seek_start(struct table_iter *ti, uint8_t typ, int index)
 {
-       struct reftable_reader_offsets *offs = reader_offsets_for(r, typ);
+       struct reftable_reader_offsets *offs = reader_offsets_for(ti->r, typ);
        uint64_t off = offs->offset;
        if (index) {
                off = offs->index_offset;
@@ -415,7 +418,7 @@ static int table_iter_seek_start(struct table_iter *ti, struct reftable_reader *
                typ = BLOCK_TYPE_INDEX;
        }
 
-       return table_iter_seek_to(ti, r, off, typ);
+       return table_iter_seek_to(ti, off, typ);
 }
 
 static int table_iter_seek_linear(struct table_iter *ti,
@@ -548,7 +551,7 @@ static int table_iter_seek_indexed(struct table_iter *ti,
                if (err != 0)
                        goto done;
 
-               err = table_iter_seek_to(ti, ti->r, index_result.u.idx.offset, 0);
+               err = table_iter_seek_to(ti, index_result.u.idx.offset, 0);
                if (err != 0)
                        goto done;
 
@@ -578,7 +581,7 @@ static int reader_seek(struct reftable_reader *r, struct reftable_iterator *it,
 {
        uint8_t typ = reftable_record_type(rec);
        struct reftable_reader_offsets *offs = reader_offsets_for(r, typ);
-       struct table_iter ti = TABLE_ITER_INIT, *p;
+       struct table_iter ti, *p;
        int err;
 
        if (!offs->is_present) {
@@ -586,7 +589,9 @@ static int reader_seek(struct reftable_reader *r, struct reftable_iterator *it,
                return 0;
        }
 
-       err = table_iter_seek_start(&ti, r, reftable_record_type(rec),
+       table_iter_init(&ti, r);
+
+       err = table_iter_seek_start(&ti, reftable_record_type(rec),
                                    !!offs->index_offset);
        if (err < 0)
                goto out;
@@ -722,15 +727,15 @@ static int reftable_reader_refs_for_unindexed(struct reftable_reader *r,
                                              struct reftable_iterator *it,
                                              uint8_t *oid)
 {
-       struct table_iter ti_empty = TABLE_ITER_INIT;
-       struct table_iter *ti = reftable_calloc(1, sizeof(*ti));
+       struct table_iter *ti;
        struct filtering_ref_iterator *filter = NULL;
        struct filtering_ref_iterator empty = FILTERING_REF_ITERATOR_INIT;
        int oid_len = hash_size(r->hash_id);
        int err;
 
-       *ti = ti_empty;
-       err = table_iter_seek_start(ti, r, BLOCK_TYPE_REF, 0);
+       REFTABLE_ALLOC_ARRAY(ti, 1);
+       table_iter_init(ti, r);
+       err = table_iter_seek_start(ti, BLOCK_TYPE_REF, 0);
        if (err < 0) {
                reftable_free(ti);
                return err;