document Conn interface better, in preparation

for per-method interface documentation
by mkdoc.pl.

implement timeouts on network reads
and use them in dns client.

also added locks on i/o to ensure writes
are not interlaced.

R=r
DELTA=340  (272 added, 25 deleted, 43 changed)
OCL=25799
CL=25874

1 files changed, 42 insertions, 0 deletions

diff --git a/src/lib/net/timeout_test.go b/src/lib/net/timeout_test.go
new file mode 100644
index 000000000..e1ce91789
--- /dev/null
+++ b/src/lib/net/timeout_test.go
@@ -0,0 +1,42 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+	"net";
+	"testing";
+	"time";
+	"os";
+)
+
+func testTimeout(t *testing.T, network, addr string) {
+	fd, err := net.Dial(network, "", addr);
+	defer fd.Close();
+	if err != nil {
+		t.Errorf("dial %s %s failed: %v", network, addr, err);
+	}
+	t0 := time.Nanoseconds();
+	fd.SetReadTimeout(1e8);	// 100ms
+	var b [100]byte;
+	n, err1 := fd.Read(b);
+	t1 := time.Nanoseconds();
+	if n != 0 || err1 != os.EAGAIN {
+		t.Errorf("fd.Read on %s %s did not return 0, EAGAIN: %v, %v", network, addr, n, err1);
+	}
+	if t1 - t0 < 0.5e8 || t1 - t0 > 1.5e8 {
+		t.Errorf("fd.Read on %s %s took %f seconds, expected 0.1", network, addr, float64(t1 - t0) / 1e9);
+	}
+}
+
+func TestTmeoutUDP(t *testing.T) {
+	testTimeout(t, "udp", "127.0.0.1:53");
+}
+
+func TestTimeoutTCP(t *testing.T) {
+	// 74.125.19.99 is www.google.com.
+	// could use dns, but dns depends on
+	// timeouts and this is the timeout test.
+	testTimeout(t, "tcp", "74.125.19.99:80");
+}