zyl/classics
mirror of https://github.com/zyllian/classics.git synced 2025-05-10 02:36:40 -07:00

read exact size of packets, fixing networking buf

Browse source
This commit is contained in:
Zoey 2024-04-21 22:24:10 -07:00
parent a06626e8cb
commit 87cf17665d
No known key found for this signature in database
GPG key ID: 8611B896D1AAFAF2
5 changed files with 109 additions and 102 deletions
Download patch file Download diff file Expand all files Collapse all files

82
src/packet.rs
View file

@ -1,4 +1,5 @@
use half::f16;
use safer_bytes::{error::Truncated, SafeBuf};
pub mod client;
pub mod server;
@ -10,79 +11,30 @@ pub const ARRAY_LENGTH: usize = 1024;
/// units in an f16 unit
pub const F16_UNITS: f32 = 32.0;
/// helper for reading packets
#[derive(Debug)]
pub struct PacketReader<'p> {
raw_packet: &'p [u8],
cursor: usize,
/// trait extending the `SafeBuf` type
pub trait SafeBufExtension: SafeBuf {
/// tries to get the next f16 in the buffer
fn try_get_f16(&mut self) -> Result<f16, Truncated>;
/// tries to get the next string in the buffer
fn try_get_string(&mut self) -> Result<String, Truncated>;
}
impl<'p> PacketReader<'p> {
/// creates a new packet reader from the given packet data
pub fn new(raw_packet: &'p [u8]) -> Self {
Self {
raw_packet,
cursor: 0,
}
impl<T> SafeBufExtension for T
where
T: SafeBuf,
{
fn try_get_f16(&mut self) -> Result<f16, Truncated> {
self.try_get_i16()
.map(|v| f16::from_f32(v as f32 / F16_UNITS))
}
/// gets the next u8 in the packet, if any
fn next_u8(&mut self) -> Option<u8> {
let r = self.raw_packet.get(self.cursor).copied();
self.cursor = self.cursor.checked_add(1).unwrap_or(self.cursor);
r
}
/// gets the next i8 in the packet, if any
fn next_i8(&mut self) -> Option<i8> {
self.next_u8().map(|b| b as i8)
}
/// gets the next u16 in the packet, if any
fn next_u16(&mut self) -> Option<u16> {
Some(u16::from_be_bytes([self.next_u8()?, self.next_u8()?]))
}
/// gets the next i16 in the packet, if any
fn next_i16(&mut self) -> Option<i16> {
self.next_u16().map(|s| s as i16)
}
/// gets the next f16 in the packet, if any
fn next_f16(&mut self) -> Option<f16> {
self.next_i16().map(|v| f16::from_f32(v as f32 / F16_UNITS))
}
/// gets the next string in the packet, if any
fn next_string(&mut self) -> Option<String> {
fn try_get_string(&mut self) -> Result<String, Truncated> {
let mut chars: Vec<char> = Vec::new();
for _ in 0..STRING_LENGTH {
chars.push(self.next_u8()? as char);
chars.push(self.try_get_u8()? as char);
}
Some(String::from_iter(chars).trim().to_string())
Ok(String::from_iter(chars).trim().to_string())
}
// /// gets the next array of the given length in the packet, if any
// fn next_array_of_length(&mut self, len: usize) -> Option<Vec<u8>> {
// let mut bytes: Vec<u8> = Vec::new();
// let mut append = true;
// for _ in 0..len {
// let b = self.next_u8()?;
// if append {
// if b == 0 {
// append = false;
// } else {
// bytes.push(b);
// }
// }
// }
// Some(bytes)
// }
// /// gets the next array of default size in the packet, if any
// fn next_array(&mut self) -> Option<Vec<u8>> {
// self.next_array_of_length(ARRAY_LENGTH)
// }
}
/// helper for writing a packet