Crate podio

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Additional methods for Read and Write

The additional methods implemented allow reading and writing integers and floats in the specified endianness.

Usage

Basically, you need to use the trait WritePodExt or ReadPodExt.

Examples

Reading

To read some value from a reader, import ReadPodExt and the needed endianness.

use podio::{ReadPodExt, BigEndian};

let slice: &[u8] = &[0x10, 0x20, 0x30, 0x40];
let mut reader = std::io::Cursor::new(slice);

let value = reader.read_u32::<BigEndian>().unwrap();

assert_eq!(value, 0x10203040);

Writing

For writing, you need to import the trait WritePodExt.

use podio::{WritePodExt, LittleEndian};

let slice: &mut [u8] = &mut [0; 2];
let mut writer = std::io::Cursor::new(slice);

writer.write_u16::<LittleEndian>(0x8802).unwrap();

assert_eq!(writer.into_inner(), &[0x02, 0x88]);

Read exact

One additional method, not really dealing with POD, is read_exact.

use podio::ReadPodExt;

let slice: &[u8] = &[0, 1, 2, 3];
let mut reader = std::io::Cursor::new(slice);

assert_eq!(reader.read_exact(1).unwrap(), [0]);
assert_eq!(reader.read_exact(2).unwrap(), [1,2]);
assert_eq!(reader.read_exact(0).unwrap(), []);
assert_eq!(reader.read_exact(1).unwrap(), [3]);
assert!(reader.read_exact(1).is_err());

Enums

Big endian. The number 0xABCD is stored [0xAB, 0xCD]
Little endian. The number 0xABCD is stored [0xCD, 0xAB]

Traits

Generic trait for endian conversions on integers
Trait implementing conversion methods for a specific endianness
Additional read methods for a io::Read
Additional write methods for a io::Write