Add accept() backoff timer + tcp idle timer + minor eventloop API improvements

1 files changed, 17 insertions, 8 deletions

diff --git a/src/listener.rs b/src/listener.rs
index 293099e..fcac06d 100644
--- a/src/listener.rs
+++ b/src/listener.rs
@@ -2,8 +2,9 @@ use mio::{Ready,Token,Event};
 use mio::tcp::TcpListener;
 use std::net::SocketAddr;
 use std::io::{Result,ErrorKind};
+use std::time::Duration;
 use config::Config;
-use eventloop::{Machine,Context,EventLoop};
+use eventloop::{Machine,Context,EventLoop,TToken};
 
 use itf_http;
 
@@ -11,7 +12,8 @@ use itf_http;
 struct Listener {
     sock: TcpListener,
     addr: SocketAddr,
-    io: Token
+    io: Token,
+    timeout: TToken,
 }
 
 
@@ -22,7 +24,8 @@ impl Listener {
         Ok(Listener {
             sock: sock,
             addr: *addr,
-            io: Token(0)
+            io: Token(0),
+            timeout: TToken(0),
         })
     }
 }
@@ -30,8 +33,8 @@ impl Listener {
 
 impl Machine for Listener {
     fn init(&mut self, ctx: &mut Context) {
-        self.io = ctx.assign();
-        ctx.register(&self.sock, self.io, Ready::readable());
+        self.io = ctx.register(&self.sock, Ready::readable());
+        self.timeout = ctx.alloc_timeout();
         info!("Listening on {}", self.addr);
     }
 
@@ -42,11 +45,13 @@ impl Machine for Listener {
                 match err.kind() {
                     ErrorKind::WouldBlock |
                     ErrorKind::Interrupted |
-                    ErrorKind::TimedOut => { },
+                    ErrorKind::TimedOut => { /* Uninteresting temporary errors */ },
                     _ => {
                         error!("Error accepting on {}: {}", self.addr, err);
-                        // If the error is persistent, we may be getting into an infinite loop.
-                        // TODO: Have a back-off timer here (especially for EMFILE).
+                        // Stop listening for short time. If this error is not persistent (like
+                        // EMFILE), it will solve itself by just waiting. Not much else we can do.
+                        ctx.deregister(&self.sock, self.io);
+                        ctx.reset_timeout(self.timeout, Duration::from_millis(500));
                     }
                 }
             },
@@ -56,6 +61,10 @@ impl Machine for Listener {
             }
         }
     }
+
+    fn timeout(&mut self, ctx: &mut Context, _: TToken) {
+        self.io = ctx.register(&self.sock, Ready::readable());
+    }
 }