next_indefinite_text_string.sql

CREATE OR REPLACE FUNCTION cbor.next_indefinite_text_string
(
    cbor BYTEA,
    encode_binary_format TEXT
)
RETURNS cbor.next_state
IMMUTABLE
BEGIN ATOMIC
WITH RECURSIVE x AS
(
    SELECT
        0 AS i,
        next_indefinite_text_string.cbor AS remainder,
        ''::TEXT AS text_string
    UNION ALL
    SELECT
        x.i + 1,
        next_item.remainder,
        x.text_string ||
        CASE
            WHEN (get_byte(x.remainder,0)>>5)&'111'::BIT(3)::INTEGER = 3
            THEN (next_item.item#>>'{}')
            ELSE cbor.raise('incorrect substructure of indefinite-length text string (may only contain definite-length strings of the same major type)',NULL,NULL::text)
        END
    FROM x
    JOIN LATERAL cbor.next_item(x.remainder, encode_binary_format) ON TRUE
    WHERE get_byte(x.remainder,0) <> 255
)
SELECT
    (
        substring(x.remainder,2),
        to_jsonb(x.text_string)
    )::cbor.next_state
FROM x
ORDER BY i DESC
FETCH FIRST ROW ONLY;
END;