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use std::io::Cursor;
use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
#[cfg(test)]
mod tests;
pub mod client;
pub mod server;
#[derive(Debug)]
pub enum ReadingError {
/// Error returned when the server fails to read data from the client.
Reading,
/// Error returned when the readed packet fails to be decoded
Decode,
}
#[derive(Debug)]
pub enum ConnectionError {
/// Error returned when a client fail to connect.
Client(String),
}
/// Error returned when a packet cannot be decoded from [Packet::decode].
#[derive(Debug)]
pub struct PacketDecodeError;
/// Enum containing all the possible packet types.
#[derive(Debug)]
pub enum Packet {
Invalid,
// Packet containing data in form of bytes.
Bytes(Vec<u8>),
/// Packet containing a [String].
String(String),
/// Packet containing a [i8].
I8(i8),
/// Packet containing a [i16].
I16(i16),
/// Packet containing a [i32].
I32(i32),
/// Packet containing a [i64].
I64(i64),
/// Packet containing a [f32].
F32(f32),
/// Packet containing a [f64].
F64(f64),
/// Packet containing a [u8].
U8(u8),
/// Packet containing a [u16].
U16(u16),
/// Packet containing a [u32].
U32(u32),
/// Packet containing a [u64].
U64(u64),
// Packet containing data in form of bytes with an identifier which can represent what type of data the packet contains.
Identified(u32, Vec<u8>),
}
impl Packet {
/// Encode the packet into bytes.
pub fn encode(&self) -> Vec<u8> {
let mut result = Vec::new();
match self {
Packet::Bytes(data) => {
result.insert(0, 1);
for _ in 0..(std::mem::size_of::<u8>() * data.len()) {
result.push(0);
}
for b in data {
result.push(*b)
}
}
Packet::String(data) => {
result.insert(0, 2);
for _ in 0..std::mem::size_of::<String>() {
result.push(0);
}
for b in data.as_bytes() {
result.push(*b);
}
}
Packet::I8(data) => {
result.insert(0, 3);
for _ in 0..std::mem::size_of::<i8>() {
result.push(0);
}
let _ = &result[1..].as_mut().write_i8(*data);
}
Packet::I16(data) => {
result.insert(0, 4);
for _ in 0..std::mem::size_of::<i16>() {
result.push(0);
}
let _ = &result[1..].as_mut().write_i16::<LittleEndian>(*data);
}
Packet::I32(data) => {
result.insert(0, 5);
for _ in 0..std::mem::size_of::<i32>() {
result.push(0);
}
let _ = &result[1..]
.as_mut()
.write_i32::<LittleEndian>(*data)
.unwrap();
}
Packet::I64(data) => {
result.insert(0, 6);
for _ in 0..std::mem::size_of::<i64>() {
result.push(0);
}
let _ = &result[1..].as_mut().write_i64::<LittleEndian>(*data);
}
Packet::F32(data) => {
result.insert(0, 7);
for _ in 0..std::mem::size_of::<f32>() {
result.push(0);
}
let _ = &result[1..].as_mut().write_f32::<LittleEndian>(*data);
}
Packet::F64(data) => {
result.insert(0, 8);
for _ in 0..std::mem::size_of::<f64>() {
result.push(0);
}
let _ = &result[1..].as_mut().write_f64::<LittleEndian>(*data);
}
Packet::U8(data) => {
result.insert(0, 9);
for _ in 0..std::mem::size_of::<u8>() {
result.push(0);
}
let _ = &result[1..].as_mut().write_u8(*data);
}
Packet::U16(data) => {
result.insert(0, 10);
for _ in 0..std::mem::size_of::<u16>() {
result.push(0);
}
let _ = &result[1..].as_mut().write_u16::<LittleEndian>(*data);
}
Packet::U32(data) => {
result.insert(0, 11);
for _ in 0..std::mem::size_of::<u32>() {
result.push(0);
}
let _: &Result<(), std::io::Error> =
&result[1..].as_mut().write_u32::<LittleEndian>(*data);
}
Packet::U64(data) => {
result.insert(0, 12);
for _ in 0..std::mem::size_of::<u64>() {
result.push(0);
}
let _ = &result[1..].as_mut().write_u64::<LittleEndian>(*data);
}
Packet::Identified(id, data) => {
result.insert(0, 13);
for _ in 0..std::mem::size_of::<u32>() {
result.push(0);
}
let _ = &result[1..].as_mut().write_u32::<LittleEndian>(*id);
for b in data {
result.push(*b)
}
}
Packet::Invalid => (),
}
result
}
/// Returns a [Packet] from a [Vec] of bytes.
pub fn decode(bytes: Vec<u8>) -> Result<Self, PacketDecodeError> {
if let Some(b) = bytes.first() {
match b {
1 => Ok(Packet::Bytes(bytes[1..].to_vec())),
2 => Ok(Packet::String(
if let Ok(s) = String::from_utf8(bytes[1..].to_vec()) {
s
} else {
return Err(PacketDecodeError);
},
)),
3 => Ok(Packet::I8(
if let Ok(n) = Cursor::new(bytes[1..].to_vec()).read_i8() {
n
} else {
return Err(PacketDecodeError);
},
)),
4 => Ok(Packet::I16(
if let Ok(n) = Cursor::new(bytes[1..].to_vec()).read_i16::<LittleEndian>() {
n
} else {
return Err(PacketDecodeError);
},
)),
5 => Ok(Packet::I32(
if let Ok(n) = Cursor::new(bytes[1..].to_vec()).read_i32::<LittleEndian>() {
n
} else {
return Err(PacketDecodeError);
},
)),
6 => Ok(Packet::I64(
if let Ok(n) = Cursor::new(bytes[1..].to_vec()).read_i64::<LittleEndian>() {
n
} else {
return Err(PacketDecodeError);
},
)),
7 => Ok(Packet::F32(
if let Ok(n) = Cursor::new(bytes[1..].to_vec()).read_f32::<LittleEndian>() {
n
} else {
return Err(PacketDecodeError);
},
)),
8 => Ok(Packet::F64(
if let Ok(n) = Cursor::new(bytes[1..].to_vec()).read_f64::<LittleEndian>() {
n
} else {
return Err(PacketDecodeError);
},
)),
9 => Ok(Packet::U8(
if let Ok(n) = Cursor::new(bytes[1..].to_vec()).read_u8() {
n
} else {
return Err(PacketDecodeError);
},
)),
10 => Ok(Packet::U16(
if let Ok(n) = Cursor::new(bytes[1..].to_vec()).read_u16::<LittleEndian>() {
n
} else {
return Err(PacketDecodeError);
},
)),
11 => Ok(Packet::U32(
if let Ok(n) = Cursor::new(bytes[1..].to_vec()).read_u32::<LittleEndian>() {
n
} else {
return Err(PacketDecodeError);
},
)),
12 => Ok(Packet::U64(
if let Ok(n) = Cursor::new(bytes[1..].to_vec()).read_u64::<LittleEndian>() {
n
} else {
return Err(PacketDecodeError);
},
)),
13 => Ok(Packet::Identified(
if let Ok(id) = Cursor::new(bytes[1..].to_vec()).read_u32::<LittleEndian>() {
id
} else {
return Err(PacketDecodeError);
},
bytes[std::mem::size_of::<u32>()..].to_vec(),
)),
_ => Ok(Packet::Invalid),
}
} else {
Err(PacketDecodeError)
}
}
}