Function _fdb_iterator_next

src/iterator.cc:829–988

}

static fdb_status _fdb_iterator_next(fdb_iterator *iterator)
{
    int cmp;
    void *key;
    size_t keylen;
    uint64_t offset;
    hbtrie_result hr = HBTRIE_RESULT_SUCCESS;
    struct docio_handle *dhandle;
    struct snap_wal_entry *snap_item = NULL;

    if (iterator->direction == FDB_ITR_REVERSE) {
        iterator->_offset = BLK_NOT_FOUND; // need to re-examine Trie/trees
        if (iterator->tree_cursor) {
            iterator->tree_cursor = avl_next(iterator->tree_cursor);
            if (iterator->tree_cursor &&
                iterator->status == FDB_ITR_WAL) {
                // if the last document was returned from WAL,
                // shift again, past curkey into next
                iterator->tree_cursor = avl_next(iterator->tree_cursor);
            }
        }
    }

    if (!iterator->tree_cursor && iterator->direction != FDB_ITR_FORWARD) {
        // In case reverse iteration went past the start, reset the
        // cursor to the start point
        iterator->tree_cursor = iterator->tree_cursor_start;
        if (iterator->status == FDB_ITR_WAL &&
            iterator->_dhandle && iterator->_get_offset != BLK_NOT_FOUND) {
            // In this case, iterator is currently pointing to the first key
            // (it implies that the first key is already returned).
            // So we need to move it forward one step.
            iterator->tree_cursor_prev = iterator->tree_cursor;
            iterator->tree_cursor = avl_next(iterator->tree_cursor);
        }
    }

start:
    key = iterator->_key;
    dhandle = iterator->handle->dhandle;

    // retrieve from hb-trie
    if (iterator->_offset == BLK_NOT_FOUND) {
        // no key waiting for being returned
        // get next key from hb-trie (or idtree)
        struct docio_object _doc;
        uint64_t _offset;
        do {
            hr = hbtrie_next(iterator->hbtrie_iterator, key,
                             &iterator->_keylen, (void*)&iterator->_offset);
            btreeblk_end(iterator->handle->bhandle);
            iterator->_offset = _endian_decode(iterator->_offset);
            if (!(iterator->opt & FDB_ITR_NO_DELETES) ||
                  hr != HBTRIE_RESULT_SUCCESS) {
                break;
            }
            // deletion check
            memset(&_doc, 0x0, sizeof(struct docio_object));