git/reftable/iter.h
Han-Wen Nienhuys 46bc0e731a reftable: read reftable files
This supports reading a single reftable file.

The commit introduces an abstract iterator type, which captures the usecases
both of reading individual refs, and iterating over a segment of the ref
namespace.

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 10:45:48 -07:00

69 lines
1.8 KiB
C

/*
Copyright 2020 Google LLC
Use of this source code is governed by a BSD-style
license that can be found in the LICENSE file or at
https://developers.google.com/open-source/licenses/bsd
*/
#ifndef ITER_H
#define ITER_H
#include "system.h"
#include "block.h"
#include "record.h"
#include "reftable-iterator.h"
#include "reftable-generic.h"
/* Returns true for a zeroed out iterator, such as the one returned from
* iterator_destroy. */
int iterator_is_null(struct reftable_iterator *it);
/* iterator that produces only ref records that point to `oid` */
struct filtering_ref_iterator {
int double_check;
struct reftable_table tab;
struct strbuf oid;
struct reftable_iterator it;
};
#define FILTERING_REF_ITERATOR_INIT \
{ \
.oid = STRBUF_INIT \
}
void iterator_from_filtering_ref_iterator(struct reftable_iterator *,
struct filtering_ref_iterator *);
/* iterator that produces only ref records that point to `oid`,
* but using the object index.
*/
struct indexed_table_ref_iter {
struct reftable_reader *r;
struct strbuf oid;
/* mutable */
uint64_t *offsets;
/* Points to the next offset to read. */
int offset_idx;
int offset_len;
struct block_reader block_reader;
struct block_iter cur;
int is_finished;
};
#define INDEXED_TABLE_REF_ITER_INIT \
{ \
.cur = { .last_key = STRBUF_INIT }, .oid = STRBUF_INIT, \
}
void iterator_from_indexed_table_ref_iter(struct reftable_iterator *it,
struct indexed_table_ref_iter *itr);
/* Takes ownership of `offsets` */
int new_indexed_table_ref_iter(struct indexed_table_ref_iter **dest,
struct reftable_reader *r, uint8_t *oid,
int oid_len, uint64_t *offsets, int offset_len);
#endif