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filters/count/count.go

-// Copyright 2015 The Chromium 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 count contains 'counter' filters for all the gae services. This
-// serves as a set of simple example filters, and also enables other filters
-// to test to see if certain underlying APIs are called when they should be
-// (e.g. for the datastore mcache filter, for example).
-package count
-
-import (
-        "sync/atomic"
-)
-
-// Entry is a success/fail pair for a single API method. It's returned
-// by the Counter interface.
-type Entry struct {
-        Successes int64
-        Errors    int64
-}
-
-// Total is a convenience function for getting the total number of calls to
-// this API. It's Successes+Errors.
-func (e Entry) Total() int64 { return e.Successes + e.Errors }
-
-func (e *Entry) up(errs ...error) error {
-        err := error(nil)
-        if len(errs) > 0 {
-                err = errs[0]
-        }
-        if err == nil {
-                atomic.AddInt64(&e.Successes, 1)
-        } else {
-                atomic.AddInt64(&e.Errors, 1)
-        }
-        return err
-}