Initial cut at an "exported variables" (exvar) package.
This handles integer-valued vars in a singleton struct, and exports functions
for incrementing, setting and getting those vars, as well as rendering all the
vars in a standard format.
Demonstrate the use of the exvar package in the http/triv server.
R=dcross,r
APPROVED=r
DELTA=122 (122 added, 0 deleted, 0 changed)
OCL=27617
CL=27622
diff --git a/src/lib/exvar_test.go b/src/lib/exvar_test.go
new file mode 100644
index 0000000..2948fc6
--- /dev/null
+++ b/src/lib/exvar_test.go
@@ -0,0 +1,54 @@
+// 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 exvar
+
+import (
+ "exvar";
+ "fmt";
+ "testing";
+)
+
+func TestSimpleCounter(t *testing.T) {
+ // Unknown exvar should be zero, and return !ok.
+ x, ok := Get("requests");
+ if x != 0 || ok {
+ t.Errorf("Get(nonexistent) = (%v, %v), want (%v, %v)",
+ x, ok, 0, false)
+ }
+
+ Increment("requests", 1);
+ Increment("requests", 3);
+ x, ok = Get("requests");
+ if x != 4 || !ok {
+ t.Errorf("Get('requests') = (%v, %v), want (%v, %v)",
+ x, ok, 4, true)
+ }
+
+ out := String();
+ if out != "requests 4\n" {
+ t.Errorf("String() = \"%v\", want \"requests 4\n\"",
+ out);
+ }
+}
+
+func hammer(name string, total int, done chan <- int) {
+ for i := 0; i < total; i++ {
+ Increment(name, 1)
+ }
+ done <- 1
+}
+
+func TestHammer(t *testing.T) {
+ Set("hammer-times", 0);
+ sync := make(chan int);
+ hammer_times := int(1e5);
+ go hammer("hammer-times", hammer_times, sync);
+ go hammer("hammer-times", hammer_times, sync);
+ <-sync;
+ <-sync;
+ if final, ok := Get("hammer-times"); final != 2 * hammer_times {
+ t.Errorf("hammer-times = %v, want %v", final, 2 * hammer_times)
+ }
+}
