1 use crate::error::Result;
2
3 use byteorder::{ReadBytesExt, WriteBytesExt};
4 use std::io::{Read, Write};
5
6 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
7 pub enum CompressionMethodId {
8 Null = 0,
9 Unsupported,
10 }
11
12 impl From<u8> for CompressionMethodId {
from(val: u8) -> Self13 fn from(val: u8) -> Self {
14 match val {
15 0 => CompressionMethodId::Null,
16 _ => CompressionMethodId::Unsupported,
17 }
18 }
19 }
20
21 #[derive(Clone, Debug, PartialEq, Eq)]
22 pub struct CompressionMethods {
23 pub ids: Vec<CompressionMethodId>,
24 }
25
26 impl CompressionMethods {
size(&self) -> usize27 pub fn size(&self) -> usize {
28 1 + self.ids.len()
29 }
30
marshal<W: Write>(&self, writer: &mut W) -> Result<()>31 pub fn marshal<W: Write>(&self, writer: &mut W) -> Result<()> {
32 writer.write_u8(self.ids.len() as u8)?;
33
34 for id in &self.ids {
35 writer.write_u8(*id as u8)?;
36 }
37
38 Ok(writer.flush()?)
39 }
40
unmarshal<R: Read>(reader: &mut R) -> Result<Self>41 pub fn unmarshal<R: Read>(reader: &mut R) -> Result<Self> {
42 let compression_methods_count = reader.read_u8()? as usize;
43 let mut ids = vec![];
44 for _ in 0..compression_methods_count {
45 let id = reader.read_u8()?.into();
46 if id != CompressionMethodId::Unsupported {
47 ids.push(id);
48 }
49 }
50
51 Ok(CompressionMethods { ids })
52 }
53 }
54
default_compression_methods() -> CompressionMethods55 pub fn default_compression_methods() -> CompressionMethods {
56 CompressionMethods {
57 ids: vec![CompressionMethodId::Null],
58 }
59 }
60