Trait Message

pub trait Message: Send {
    // Required methods
    fn write(&self, writer: &mut dyn Write) -> RdpResult<()>;
    fn read(&mut self, reader: &mut dyn Read) -> RdpResult<()>;
    fn length(&self) -> u64;
    fn visit(&self) -> DataType<'_>;
    fn options(&self) -> MessageOption;
}

All is a message

A message can be Read or Write from a Stream

Required Methods

fn write(&self, writer: &mut dyn Write) -> RdpResult<()>

Write node to the Stream

Write current element into a writable stream

fn read(&mut self, reader: &mut dyn Read) -> RdpResult<()>

Read node from stream

Read and set current variable from readable stream

fn length(&self) -> u64

Length in bytes of current element

fn visit(&self) -> DataType<'_>

Cast value on Message Tree

Visit value and try to return inner type This is based on Tree visitor pattern

fn options(&self) -> MessageOption

Retrieve options of a subtype

Allow subtype to show some options That will impact current operation on parent like skipping some fields of a component

Implementations on Foreign Types

impl Message for u8

u8 message

Implement Message trait for basic type u8

fn write(&self, writer: &mut dyn Write) -> RdpResult<()>

Write u8 value into stream

Example

    let mut s = Cursor::new(Vec::new());
    let value : u8 = 8;
    value.write(&mut s);
    assert_eq!(*s.get_ref(), vec![8 as u8]);

fn read(&mut self, reader: &mut dyn Read) -> RdpResult<()>

Read u8 value from stream

Example

    let mut stream = Cursor::new(vec![8]);
    let mut value = 0 as u8;
    value.read(&mut stream); // set the value according to stream content
    assert_eq!(value, 8);

fn length(&self) -> u64

Size in byte of wrapped value 1 in case of u8

Example

    let x : u8 = 0;
    assert_eq!(x.length(), 1);

fn visit(&self) -> DataType<'_>

Use visitor pattern to retrieve leaf value in case of node component

Example

    let x : u8 = 8;
    if let DataType::U8(value) = x.visit() {
        assert_eq!(value, 8)
    }
    else {
        panic!("Invalid cast");
    }

fn options(&self) -> MessageOption

Retrieve option of a subnode

Allow a parent to retrieve some optional value That will influence the current node operation like skipping field of a component

This kind of node have no option

impl Message for Vec<u8>

fn write(&self, writer: &mut dyn Write) -> RdpResult<()>

fn read(&mut self, reader: &mut dyn Read) -> RdpResult<()>

fn length(&self) -> u64

fn visit(&self) -> DataType<'_>

fn options(&self) -> MessageOption

impl<T: Message> Message for Option<T>

This is an optional fields Actually always write but read if and only if the reader buffer could read the size of inner Message

fn write(&self, writer: &mut dyn Write) -> RdpResult<()>

Write an optional message Actually always try to write

Example

use std::io::Cursor;
use rdp::model::data::Message;
let mut s1 = Cursor::new(vec![]);
Some(4).write(&mut s1);
assert_eq!(s1.into_inner(), [4]);
let mut s2 = Cursor::new(vec![]);
Option::<u8>::None.write(&mut s2);
assert_eq!(s2.into_inner(), [])

fn read(&mut self, reader: &mut dyn Read) -> RdpResult<()>

Read an optional field Read the value if and only if there is enough space in the reader

Example

#[macro_use]
    let mut s1 = Cursor::new(vec![1, 0, 0, 0]);
    let mut x = Some(U32::LE(0));
    x.read(&mut s1);
    assert_eq!(1, cast!(DataType::U32, x).unwrap());

    let mut s2 = Cursor::new(vec![1, 0, 0]);
    let mut y = Some(U32::LE(0));
    y.read(&mut s2);
    assert!(y == None);

    let mut s3 = Cursor::new(vec![1, 0, 0]);
    // case in component
    let mut z = component![
        "optional" => Some(U32::LE(0))
    ];
    z.read(&mut s3);
    assert!(is_none!(z["optional"]))

fn length(&self) -> u64

This compute the length of the optionaln field

Example

use rdp::model::data::{U32, Message};
assert_eq!(Some(U32::LE(4)).length(), 4);
assert_eq!(Option::<U32>::None.length(), 0);

fn visit(&self) -> DataType<'_>

Visitor pattern for optional field

Example

#[macro_use]
    assert_eq!(4, cast!(DataType::U32, Some(U32::LE(4))).unwrap());
    assert!(is_none!(Option::<U32>::None));

fn options(&self) -> MessageOption

Implementors

impl Message for Component

impl Message for Trame

Trame is a Message too

impl Message for U16

impl Message for U32

impl<T: 'static + Message> Message for Array<T>

Implement the message trait for Array

impl<T: Message + Clone + PartialEq> Message for Check<T>

impl<T: Message> Message for DynOption<T>

Dynamic option is a transparent object for the inner