Initial commit

crates/librqbit/src/peer_id.rs

@@ -0,0 +1,45 @@
+#[derive(Debug)]
+pub enum AzureusStyleKind {
+    Deluge,
+    LibTorrent,
+    Transmission,
+    Other([char; 2]),
+}
+
+#[derive(Debug)]
+pub struct AzureusStyle {
+    pub kind: AzureusStyleKind,
+    pub version: [char; 4],
+}
+
+impl AzureusStyleKind {
+    pub const fn from_bytes(b1: u8, b2: u8) -> Self {
+        match &[b1, b2] {
+            b"DE" => AzureusStyleKind::Deluge,
+            b"lt" | b"LT" => AzureusStyleKind::LibTorrent,
+            b"TR" => AzureusStyleKind::Transmission,
+            _ => AzureusStyleKind::Other([b1 as char, b2 as char]),
+        }
+    }
+}
+
+fn try_decode_azureus_style(p: &[u8; 20]) -> Option<AzureusStyle> {
+    if !(p[0] == b'-' && p[7] == b'-') {
+        return None;
+    }
+    let mut version = ['0'; 4];
+    for (i, c) in (&p[3..7]).iter().copied().enumerate() {
+        version[i] = c as char;
+    }
+    let kind = AzureusStyleKind::from_bytes(p[1], p[2]);
+    Some(AzureusStyle { kind, version })
+}
+
+#[derive(Debug)]
+pub enum PeerId {
+    AzureusStyle(AzureusStyle),
+}
+
+pub fn try_decode_peer_id(p: [u8; 20]) -> Option<PeerId> {
+    Some(PeerId::AzureusStyle(try_decode_azureus_style(&p)?))
+}