/// Decode `TransportParameters` from buffer
Decode `TransportParameters` from buffer
Decode ` TransportParameters ` from buffer
pub fn read<R: Buf>(side: Side, r: &mut R) -> Result<Self, Error> {
        // Initialize to protocol-specified defaults
        let mut params = TransportParameters::default();
        let params_len = r.get::<u16>()?;
        if params_len as usize != r.remaining() {
            return Err(Error::Malformed);
        }
        // State to check for duplicate transport parameters.
        macro_rules! param_state {
            {$($(#[$doc:meta])* $name:ident ($code:expr) = $default:expr,)*} => {{
                struct ParamState {
                    $($name: bool,)*
                }
                ParamState {
                    $($name: false,)*
                }
            }}
        }
        let mut got = apply_params!(param_state);
        while r.has_remaining() {
            if r.remaining() < 4 {
                return Err(Error::Malformed);
            }
            let id = r.get::<u16>().unwrap();
            let len = r.get::<u16>().unwrap();
            if r.remaining() < len as usize {
                return Err(Error::Malformed);
            }
            match id {
                0x0000 => {
                    if len > MAX_CID_SIZE as u16 || params.original_connection_id.is_some() {
                        return Err(Error::Malformed);
                    }
                    let mut staging = [0; MAX_CID_SIZE];
                    r.copy_to_slice(&mut staging[0..len as usize]);
                    params.original_connection_id =
                        Some(ConnectionId::new(&staging[0..len as usize]));
                }
                0x0002 => {
                    if len != 16 || params.stateless_reset_token.is_some() {
                        return Err(Error::Malformed);
                    }
                    let mut tok = [0; RESET_TOKEN_SIZE];
                    r.copy_to_slice(&mut tok);
                    params.stateless_reset_token = Some(tok.into());
                }
                0x000c => {
                    if len != 0 || params.disable_active_migration {
                        return Err(Error::Malformed);
                    }
                    params.disable_active_migration = true;
                }
                0x000d => {
                    if params.preferred_address.is_some() {
                        return Err(Error::Malformed);
                    }
                    params.preferred_address =
                        Some(PreferredAddress::read(&mut r.take(len as usize))?);
                }
                0x0020 => {
                    if len > 8 || params.max_datagram_frame_size.is_some() {
                        return Err(Error::Malformed);
                    }
                    params.max_datagram_frame_size = Some(r.get().unwrap());
                }
                _ => {
                    macro_rules! parse {
                        {$($(#[$doc:meta])* $name:ident ($code:expr) = $default:expr,)*} => {
                            match id {
                                $($code => {
                                    params.$name = r.get_var()?;
                                    if len != VarInt::from_u64(params.$name).unwrap().size() as u16 || got.$name { return Err(Error::Malformed); }
                                    got.$name = true;
                                })*
                                _ => r.advance(len as usize),
                            }
                        }
                    }
                    apply_params!(parse);
                }
            }
        }
        // Semantic validation
        if params.ack_delay_exponent > 20
            || params.max_ack_delay >= 1 << 14
            || (side.is_server()
                && (params.original_connection_id.is_some()
                    || params.stateless_reset_token.is_some()
                    || params.preferred_address.is_some()))
        {
            return Err(Error::IllegalValue);
        }
        Ok(params)
    }
pub fn read < R : Buf > ( side : Side , r : & mut R ) -> Result < Self , Error > { // Initialize to protocol-specified defaults let mut params = TransportParameters :: default ( ) ; let params_len = r . get :: < u16 > ( ) ? ; if params_len as usize != r . remaining ( ) { return Err ( Error :: Malformed ) ; } // State to check for duplicate transport parameters. macro_rules! param_state { { $ ( $ ( [ $doc : meta ] ) * $name : ident ( $code : expr ) $default : expr ) * } => { { struct ParamState { $ ( $name bool ) * } ParamState { $ ( $name false ) * } } } } let mut got = apply_params ! ( param_state ) ; while r . has_remaining ( ) { if r . remaining ( ) < 4 { return Err ( Error :: Malformed ) ; } let id = r . get :: < u16 > ( ) . unwrap ( ) ; let len = r . get :: < u16 > ( ) . unwrap ( ) ; if r . remaining ( ) < len as usize { return Err ( Error :: Malformed ) ; } match id { 0x0000 => { if len > MAX_CID_SIZE as u16 || params . original_connection_id . is_some ( ) { return Err ( Error :: Malformed ) ; } let mut staging = [ 0 ; MAX_CID_SIZE ] ; r . copy_to_slice ( & mut staging [ 0 .. len as usize ] ) ; params . original_connection_id = Some ( ConnectionId :: new ( & staging [ 0 .. len as usize ] ) ) ; } 0x0002 => { if len != 16 || params . stateless_reset_token . is_some ( ) { return Err ( Error :: Malformed ) ; } let mut tok = [ 0 ; RESET_TOKEN_SIZE ] ; r . copy_to_slice ( & mut tok ) ; params . stateless_reset_token = Some ( tok . into ( ) ) ; } 0x000c => { if len != 0 || params . disable_active_migration { return Err ( Error :: Malformed ) ; } params . disable_active_migration = true ; } 0x000d => { if params . preferred_address . is_some ( ) { return Err ( Error :: Malformed ) ; } params . preferred_address = Some ( PreferredAddress :: read ( & mut r . take ( len as usize ) ) ? ) ; } 0x0020 => { if len > 8 || params . max_datagram_frame_size . is_some ( ) { return Err ( Error :: Malformed ) ; } params . max_datagram_frame_size = Some ( r . get ( ) . unwrap ( ) ) ; } _ => { macro_rules! parse { { $ ( $ ( [ $doc : meta ] ) * $name : ident ( $code : expr ) $default : expr ) * } => { match id { $ ( $code { params $name r get_var ( ) if len VarInt from_u64 ( params $name ) unwrap ( ) size ( ) as u16 got $name { return Err ( Error Malformed ) } got $name true } ) * r advance ( len as usize ) } } } apply_params ! ( parse ) ; } } } // Semantic validation if params . ack_delay_exponent > 20 || params . max_ack_delay >= 1 << 14 || ( side . is_server ( ) && ( params . original_connection_id . is_some ( ) || params . stateless_reset_token . is_some ( ) || params . preferred_address . is_some ( ) ) ) { return Err ( Error :: IllegalValue ) ; } Ok ( params ) }
Decode `TransportParameters` from buffer
Decode ` TransportParameters ` from buffer
side
Side
r
&mut R