more reasonable tracking of open FDs

src/daemon_tokfd.rs

@@ -0,0 +1,38 @@
+use std::os::fd::RawFd;
+
+use iddqd::BiHashItem;
+use mio::Token;
+
+#[derive(Copy)]
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct TokenFd {
+    pub token: Token,
+    pub fd: RawFd,
+}
+
+impl BiHashItem for TokenFd {
+    type K1<'a> = Token;
+    type K2<'a> = RawFd;
+
+    fn key1(&self) -> Token {
+        self.token
+    }
+
+    fn key2(&self) -> RawFd {
+        self.fd
+    }
+
+    iddqd::bi_upcast!();
+}
+
+impl From<TokenFd> for (Token, RawFd) {
+    fn from(TokenFd { token, fd }: TokenFd) -> (Token, RawFd) {
+        (token, fd)
+    }
+}
+
+impl From<(Token, RawFd)> for TokenFd {
+    fn from((token, fd): (Token, RawFd)) -> TokenFd {
+        TokenFd { token, fd }
+    }
+}