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reverse iterator

This commit is contained in:
MikeTuev 2022-04-24 01:25:50 +05:00 committed by GitHub
parent a65a323508
commit 9b021c3056
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@ -129,6 +129,41 @@ static fdb_err_t read_tsl(fdb_tsdb_t db, fdb_tsl_t tsl)
return FDB_NO_ERR;
}
static uint32_t get_prev_sector_addr(fdb_tsdb_t db, tsdb_sec_info_t pre_sec, uint32_t traversed_len)
{
/* check if we are not yet traversed along whole db */
if (db_sec_size(db) + traversed_len <= db_max_size(db))
{
if (pre_sec->addr >= db_sec_size(db))
{
/* the next sector is previous sector */
return pre_sec->addr - db_sec_size(db);
} else {
/* the next sector is the last sector */
return db_max_size(db) - db_sec_size(db);
}
} else {
/* finished */
return FAILED_ADDR;
}
}
static uint32_t get_prev_tsl_addr(tsdb_sec_info_t sector, fdb_tsl_t pre_tsl)
{
uint32_t addr = FAILED_ADDR;
if (sector->status == FDB_SECTOR_STORE_EMPTY) {
return FAILED_ADDR;
}
if (pre_tsl->addr.index - LOG_IDX_DATA_SIZE >= sector->addr + SECTOR_HDR_DATA_SIZE) {
addr = pre_tsl->addr.index - LOG_IDX_DATA_SIZE;
} else {
/* no TSL */
return FAILED_ADDR;
}
return addr;
}
static uint32_t get_next_sector_addr(fdb_tsdb_t db, tsdb_sec_info_t pre_sec, uint32_t traversed_len)
{
if (traversed_len + db_sec_size(db) <= db_max_size(db)) {
@ -408,6 +443,54 @@ fdb_err_t fdb_tsl_append(fdb_tsdb_t db, fdb_blob_t blob)
return result;
}
/**
* The TSDB reverse iterator for each TSL.
*
* @param db database object
* @param cb callback
* @param arg callback argument
*/
void fdb_tsl_iter_rev(fdb_tsdb_t db, fdb_tsl_cb cb, void *arg)
{
struct tsdb_sec_info sector;
uint32_t sec_addr, traversed_len = 0;
struct fdb_tsl tsl;
if (!db_init_ok(db)) {
FDB_INFO("Error: TSL (%s) isn't initialize OK.\n", db_name(db));
}
if (cb == NULL) {
return;
}
sec_addr = db->cur_sec.addr;
/* search all sectors */
do {
traversed_len += db_sec_size(db);
if (read_sector_info(db, sec_addr, &sector, false) != FDB_NO_ERR) {
continue;
}
/* sector has TSL */
if (sector.status == FDB_SECTOR_STORE_USING || sector.status == FDB_SECTOR_STORE_FULL) {
if (sector.status == FDB_SECTOR_STORE_USING) {
/* copy the current using sector status */
sector = db->cur_sec;
tsl.addr.index = db->cur_sec.empty_idx - LOG_IDX_DATA_SIZE;
} else
tsl.addr.index = sector.end_idx;
/* search all TSL */
do {
read_tsl(db, &tsl);
/* iterator is interrupted when callback return true */
if (cb(&tsl, arg)) {
return;
}
} while ((tsl.addr.index = get_prev_tsl_addr(&sector, &tsl)) != FAILED_ADDR);
} else
if (sector.status == FDB_SECTOR_STORE_EMPTY || sector.status == FDB_SECTOR_STORE_UNUSED) return;
} while ((sec_addr = get_prev_sector_addr(db, &sector, traversed_len)) != FAILED_ADDR);
}
/**
* The TSDB iterator for each TSL.
*