blob: 416a9f6996bac0701d3d47b9bd71327b732d1b28 [file] [log] [blame]
/*
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
*/
#include "iter.h"
#include "system.h"
#include "block.h"
#include "constants.h"
#include "reader.h"
#include "reftable-error.h"
int iterator_seek(struct reftable_iterator *it, struct reftable_record *want)
{
return it->ops->seek(it->iter_arg, want);
}
int iterator_next(struct reftable_iterator *it, struct reftable_record *rec)
{
return it->ops->next(it->iter_arg, rec);
}
static int empty_iterator_seek(void *arg UNUSED, struct reftable_record *want UNUSED)
{
return 0;
}
static int empty_iterator_next(void *arg UNUSED, struct reftable_record *rec UNUSED)
{
return 1;
}
static void empty_iterator_close(void *arg UNUSED)
{
}
static struct reftable_iterator_vtable empty_vtable = {
.seek = &empty_iterator_seek,
.next = &empty_iterator_next,
.close = &empty_iterator_close,
};
void iterator_set_empty(struct reftable_iterator *it)
{
assert(!it->ops);
it->iter_arg = NULL;
it->ops = &empty_vtable;
}
static void filtering_ref_iterator_close(void *iter_arg)
{
struct filtering_ref_iterator *fri = iter_arg;
strbuf_release(&fri->oid);
reftable_iterator_destroy(&fri->it);
}
static int filtering_ref_iterator_seek(void *iter_arg,
struct reftable_record *want)
{
struct filtering_ref_iterator *fri = iter_arg;
return iterator_seek(&fri->it, want);
}
static int filtering_ref_iterator_next(void *iter_arg,
struct reftable_record *rec)
{
struct filtering_ref_iterator *fri = iter_arg;
struct reftable_ref_record *ref = &rec->u.ref;
int err = 0;
while (1) {
err = reftable_iterator_next_ref(&fri->it, ref);
if (err != 0) {
break;
}
if (ref->value_type == REFTABLE_REF_VAL2 &&
(!memcmp(fri->oid.buf, ref->value.val2.target_value,
fri->oid.len) ||
!memcmp(fri->oid.buf, ref->value.val2.value,
fri->oid.len)))
return 0;
if (ref->value_type == REFTABLE_REF_VAL1 &&
!memcmp(fri->oid.buf, ref->value.val1, fri->oid.len)) {
return 0;
}
}
reftable_ref_record_release(ref);
return err;
}
static struct reftable_iterator_vtable filtering_ref_iterator_vtable = {
.seek = &filtering_ref_iterator_seek,
.next = &filtering_ref_iterator_next,
.close = &filtering_ref_iterator_close,
};
void iterator_from_filtering_ref_iterator(struct reftable_iterator *it,
struct filtering_ref_iterator *fri)
{
assert(!it->ops);
it->iter_arg = fri;
it->ops = &filtering_ref_iterator_vtable;
}
static void indexed_table_ref_iter_close(void *p)
{
struct indexed_table_ref_iter *it = p;
block_iter_close(&it->cur);
reftable_block_done(&it->block_reader.block);
reftable_free(it->offsets);
strbuf_release(&it->oid);
}
static int indexed_table_ref_iter_next_block(struct indexed_table_ref_iter *it)
{
uint64_t off;
int err = 0;
if (it->offset_idx == it->offset_len) {
it->is_finished = 1;
return 1;
}
reftable_block_done(&it->block_reader.block);
off = it->offsets[it->offset_idx++];
err = reader_init_block_reader(it->r, &it->block_reader, off,
BLOCK_TYPE_REF);
if (err < 0) {
return err;
}
if (err > 0) {
/* indexed block does not exist. */
return REFTABLE_FORMAT_ERROR;
}
block_iter_seek_start(&it->cur, &it->block_reader);
return 0;
}
static int indexed_table_ref_iter_seek(void *p UNUSED,
struct reftable_record *want UNUSED)
{
BUG("seeking indexed table is not supported");
return -1;
}
static int indexed_table_ref_iter_next(void *p, struct reftable_record *rec)
{
struct indexed_table_ref_iter *it = p;
struct reftable_ref_record *ref = &rec->u.ref;
while (1) {
int err = block_iter_next(&it->cur, rec);
if (err < 0) {
return err;
}
if (err > 0) {
err = indexed_table_ref_iter_next_block(it);
if (err < 0) {
return err;
}
if (it->is_finished) {
return 1;
}
continue;
}
/* BUG */
if (!memcmp(it->oid.buf, ref->value.val2.target_value,
it->oid.len) ||
!memcmp(it->oid.buf, ref->value.val2.value, it->oid.len)) {
return 0;
}
}
}
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)
{
struct indexed_table_ref_iter empty = INDEXED_TABLE_REF_ITER_INIT;
struct indexed_table_ref_iter *itr = reftable_calloc(1, sizeof(*itr));
int err = 0;
*itr = empty;
itr->r = r;
strbuf_add(&itr->oid, oid, oid_len);
itr->offsets = offsets;
itr->offset_len = offset_len;
err = indexed_table_ref_iter_next_block(itr);
if (err < 0) {
reftable_free(itr);
} else {
*dest = itr;
}
return err;
}
static struct reftable_iterator_vtable indexed_table_ref_iter_vtable = {
.seek = &indexed_table_ref_iter_seek,
.next = &indexed_table_ref_iter_next,
.close = &indexed_table_ref_iter_close,
};
void iterator_from_indexed_table_ref_iter(struct reftable_iterator *it,
struct indexed_table_ref_iter *itr)
{
assert(!it->ops);
it->iter_arg = itr;
it->ops = &indexed_table_ref_iter_vtable;
}
void reftable_iterator_destroy(struct reftable_iterator *it)
{
if (!it->ops)
return;
it->ops->close(it->iter_arg);
it->ops = NULL;
FREE_AND_NULL(it->iter_arg);
}
int reftable_iterator_seek_ref(struct reftable_iterator *it,
const char *name)
{
struct reftable_record want = {
.type = BLOCK_TYPE_REF,
.u.ref = {
.refname = (char *)name,
},
};
return it->ops->seek(it->iter_arg, &want);
}
int reftable_iterator_next_ref(struct reftable_iterator *it,
struct reftable_ref_record *ref)
{
struct reftable_record rec = {
.type = BLOCK_TYPE_REF,
.u = {
.ref = *ref
},
};
int err = iterator_next(it, &rec);
*ref = rec.u.ref;
return err;
}
int reftable_iterator_seek_log_at(struct reftable_iterator *it,
const char *name, uint64_t update_index)
{
struct reftable_record want = {
.type = BLOCK_TYPE_LOG,
.u.log = {
.refname = (char *)name,
.update_index = update_index,
},
};
return it->ops->seek(it->iter_arg, &want);
}
int reftable_iterator_seek_log(struct reftable_iterator *it,
const char *name)
{
return reftable_iterator_seek_log_at(it, name, ~((uint64_t) 0));
}
int reftable_iterator_next_log(struct reftable_iterator *it,
struct reftable_log_record *log)
{
struct reftable_record rec = {
.type = BLOCK_TYPE_LOG,
.u = {
.log = *log,
},
};
int err = iterator_next(it, &rec);
*log = rec.u.log;
return err;
}