add all files from Hong

config/errors.go

@@ -0,0 +1,32 @@
+// Copyright 2018-present the CoreDHCP Authors. All rights reserved
+// This source code is licensed under the MIT license found in the
+// LICENSE file in the root directory of this source tree.
+
+package config
+
+import (
+	"fmt"
+)
+
+// ConfigError is an error type returned upon configuration errors.
+type ConfigError struct {
+	err error
+}
+
+// ConfigErrorFromString returns a ConfigError from the given error string.
+func ConfigErrorFromString(format string, args ...interface{}) *ConfigError {
+	return &ConfigError{
+		err: fmt.Errorf(format, args...),
+	}
+}
+
+// ConfigErrorFromError returns a ConfigError from the given error object.
+func ConfigErrorFromError(err error) *ConfigError {
+	return &ConfigError{
+		err: err,
+	}
+}
+
+func (ce ConfigError) Error() string {
+	return fmt.Sprintf("error parsing config: %v", ce.err)
+}