Watto

Utilities for parsing and serializing Plain Old Data.

Pod

The API is primarily defined on the [Pod] trait, which can be implemented for #[repr(C)] types. It is then possible to get a reference to that [Pod] or a slice thereof directly from an underlying buffer. Similarly, the [Pod] can also be turned into its underlying buffer as well, for example to write it out into an output buffer.

Features

writer: Exports an additional [Writer] wrapping a [std::io::Write] which allows explicitly aligning the output buffer by adding padding bytes.

strings: Exports a [StringTable] for serializing and reading deduplicated strings.

End-to-End Example

```rust use std::mem; use std::io::Write;

use watto::Pod;

/// Our format looks like this: /// * A header, containing the number of As. /// * An aligned slice of As (length given by the header) /// * An aligned slice of Bs (length implicitly given by end of buffer)

[repr(C)]

struct Header { version: u32, num_as: u32, } unsafe impl Pod for Header {}

[repr(C)]

[derive(Debug, PartialEq)]

struct A(u16); unsafe impl Pod for A {}

[repr(C)]

[derive(Debug, PartialEq)]

struct B(u64); unsafe impl Pod for B {}

// Writing into an output buffer: let mut writer = watto::Writer::new(vec![]);

writer.writeall(Header { version: 1, numas: 3 }.asbytes()).unwrap(); writer.alignto(mem::alignof::()).unwrap(); writer.writeall(&[A(1), A(2), A(3)].asbytes()).unwrap(); writer.alignto(mem::alignof::()).unwrap(); writer.writeall(&[B(4), B(5), B(6)].as_bytes()).unwrap();