Trait rustbus::wire::marshal::traits::Marshal

pub trait Marshal: Signature {
    pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>;
}

The Marshal trait allows to push any type onto an message_builder::OutMessage as a parameter. There are some useful implementations here for slices and hashmaps which map to arrays and dicts in the dbus message.

The way dbus structs are represented is with rust tuples. This lib provides Marshal impls for tuples with up to 5 elements. If you need more you can just copy the impl and extend it to how many different entries you need.

There is a crate (rustbus_derive) for deriving Marshal impls with #[derive(rustbus_derive::Marshal)]. This should work for most of your needs. You can of course derive Signature as well.

If there are special needs, you can implement Marshal for your own structs:

struct MyStruct {
    x: u64,
    y: String,
}

use rustbus::ByteOrder;
use rustbus::signature;
use rustbus::wire::util;
use rustbus::Marshal;
use rustbus::wire::marshal::MarshalContext;
use rustbus::Signature;
impl Signature for &MyStruct {
    fn signature() -> signature::Type {
        signature::Type::Container(signature::Container::Struct(vec![
            u64::signature(),
            String::signature(),
        ]))
    }

    fn alignment() -> usize {
        8
    }
}    
impl Marshal for &MyStruct {
    fn marshal(
        &self,
        ctx: &mut MarshalContext,
    ) -> Result<(), rustbus::Error> {
        // always align to 8 at the start of a struct!
        ctx.align_to(8);
        self.x.marshal(ctx)?;
        self.y.marshal(ctx)?;
        Ok(())
    }
}

Implementing for your own structs

There are some rules you need to follow, or the messages will be malformed:

1. Structs need to be aligned to 8 bytes. Use ctx.align_to(8); to do that. If your type is marshalled as a primitive type you still need to align to that types alignment.
2. If you write your own dict type, you need to align every key-value pair at 8 bytes like a struct
3. The signature needs to be correct, or the message will be malformed
4. The alignment must report the correct number. This does not need to be a constant like in the example, but it needs to be consistent with the type the signature() function returns. If you are not sure, just use Self::signature().get_alignment().

Required methods

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

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Implementations on Foreign Types

impl<P: Marshal> Marshal for &P

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl Marshal for ()

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl<E: Marshal> Marshal for (E,)

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl<E1: Marshal, E2: Marshal> Marshal for (E1, E2)

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl<E1: Marshal, E2: Marshal, E3: Marshal> Marshal for (E1, E2, E3)

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl<E1: Marshal, E2: Marshal, E3: Marshal, E4: Marshal> Marshal for (E1, E2, E3, E4)

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl<E1: Marshal, E2: Marshal, E3: Marshal, E4: Marshal, E5: Marshal> Marshal for (E1, E2, E3, E4, E5)

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl<E: Marshal> Marshal for Vec<E>

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl<E: Marshal> Marshal for [E]

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl<E: Marshal> Marshal for &[E]

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl<K: Marshal, V: Marshal> Marshal for HashMap<K, V>

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl Marshal for u64

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl Marshal for i64

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl Marshal for u32

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl Marshal for i32

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl Marshal for u16

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl Marshal for i16

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl Marshal for u8

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl Marshal for bool

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl Marshal for String

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl Marshal for &str

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl Marshal for &dyn AsRawFd

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

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Implementors

impl Marshal for SignatureWrapper<'_>

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl Marshal for UnixFd

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl<'a, E: Copy + Marshal> Marshal for OptimizedMarshal<'a, E>

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

impl<S: AsRef<str>> Marshal for ObjectPath<S>

pub fn marshal(&self, ctx: &mut MarshalContext<'_, '_>) -> Result<(), Error>

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