FlashDB的TSDB数据查询问题

发布于 2021-12-26 07:39:22 浏览：1929 订阅该版

2 个回答

chenls 2021-12-30

这家伙很懒，什么也没写！

可以使用这个接口的回调函数，回调函数需要自行封装。
```c
/**
 * The TSDB iterator for each TSL by timestamp.
 *
 * @param db database object
 * @param from starting timestap
 * @param to ending timestap
 * @param cb callback
 * @param arg callback argument
 */
void fdb_tsl_iter_by_time(fdb_tsdb_t db, fdb_time_t from, fdb_time_t to, fdb_tsl_cb cb, void *cb_arg)
{
    struct tsdb_sec_info sector;
    uint32_t sec_addr, oldest_addr = db->oldest_addr, traversed_len = 0;
    struct fdb_tsl tsl;
    bool found_start_tsl = false;

if (!db_init_ok(db)) {
        FDB_INFO("Error: TSL (%s) isn't initialize OK.\n", db_name(db));
    }

//    FDB_INFO("from %s", ctime((const time_t * )&from));
//    FDB_INFO("to %s", ctime((const time_t * )&to));

if (cb == NULL) {
        return;
    }

sec_addr = oldest_addr;
    /* search all sectors */
    do {
        if (read_sector_info(db, sec_addr, §or, 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;
            }
            if ((!found_start_tsl && ((from >= sector.start_time && from <= sector.end_time)
                            || (sec_addr == oldest_addr && from <= sector.start_time))) || (found_start_tsl)) {
                uint32_t start = sector.addr + SECTOR_HDR_DATA_SIZE, end = sector.end_idx;

found_start_tsl = true;
                /* search start TSL address, using binary search algorithm */
                while (start <= end) {
                    tsl.addr.index = start + ((end - start) / 2 + 1) / LOG_IDX_DATA_SIZE * LOG_IDX_DATA_SIZE;
                    read_tsl(db, &tsl);
                    if (tsl.time < from) {
                        start = tsl.addr.index + LOG_IDX_DATA_SIZE;
                    } else {
                        end = tsl.addr.index - LOG_IDX_DATA_SIZE;
                    }
                }
                tsl.addr.index = start;
                /* search all TSL */
                do {
                    read_tsl(db, &tsl);
                    if (tsl.time >= from && tsl.time <= to) 
                    {
                        /* iterator is interrupted when callback return true */
                        if (cb(&tsl, cb_arg)) {
                            return;
                        }
                    } else {
                        return;
                    }
                } while ((tsl.addr.index = get_next_tsl_addr(§or, &tsl)) != FAILED_ADDR);
            }
        } else if (sector.status == FDB_SECTOR_STORE_EMPTY) {
            return;
        }
        traversed_len += db_sec_size(db);
    } while ((sec_addr = get_next_sector_addr(db, §or, traversed_len)) != FAILED_ADDR);
}
```