Changeset 703 in code for trunk/conn.go

Timestamp:

Nov 17, 2021, 12:13:55 PM (4 years ago)

Author:

contact

Message:

Introduce conn.NewContext

This function wraps a parent context, and returns a new context
cancelled when the connection is closed. This will make it so
operations started from downstreamConn.handleMessage will be
cancelled when the connection is closed.

File:

• trunk/conn.go (modified) (4 diffs)

trunk/conn.go

@@ -173 +173 @@
         outgoing chan<- *irc.Message
         closed   bool
+        closedCh chan struct{}
 }
 
@@ -182 +183 @@
                 outgoing: outgoing,
                 logger:   options.Logger,
+                closedCh: make(chan struct{}),
         }
 
@@ -238 +240 @@
         c.closed = true
         close(c.outgoing)
+        close(c.closedCh)
         return err
 }
@@ -278 +281 @@
         return c.conn.LocalAddr()
 }
+
+// NewContext returns a copy of the parent context with a new Done channel. The
+// returned context's Done channel is closed when the connection is closed,
+// when the returned cancel function is called, or when the parent context's
+// Done channel is closed, whichever happens first.
+//
+// Canceling this context releases resources associated with it, so code should
+// call cancel as soon as the operations running in this Context complete.
+func (c *conn) NewContext(parent context.Context) (context.Context, context.CancelFunc) {
+        ctx, cancel := context.WithCancel(parent)
+
+        go func() {
+                defer cancel()
+
+                select {
+                case <-ctx.Done():
+                        // The parent context has been cancelled, or the caller has called
+                        // cancel()
+                case <-c.closedCh:
+                        // The connection has been closed
+                }
+        }()
+
+        return ctx, cancel
+}