Function base64::engine::general_purpose::decode::complete_quads_len

pub(crate) fn complete_quads_len(
    input: &[u8],
    input_len_rem: usize,
    output_len: usize,
    decode_table: &[u8; 256],
) -> Result<usize, DecodeSliceError>

Returns the length of complete quads, except for the last one, even if it is complete.

Returns an error if the output len is not big enough for decoding those complete quads, or if the input % 4 == 1, and that last byte is an invalid value other than a pad byte.

• input is the base64 input
• input_len_rem is input len % 4
• output_len is the length of the output slice