luci-go: Tools for working with BSD style ar archives.

common/archive/ar/errors.go

Index: common/archive/ar/errors.go
diff --git a/common/archive/ar/errors.go b/common/archive/ar/errors.go
new file mode 100644
index 0000000000000000000000000000000000000000..6cf8e5d85feafe32384f0365fa40cbb057d66b74
--- /dev/null
+++ b/common/archive/ar/errors.go
@@ -0,0 +1,44 @@
+// Copyright 2016 The LUCI Authors. All rights reserved.
+// Use of this source code is governed under the Apache License, Version 2.0
+// that can be found in the LICENSE file.
+
+// Write an ar archive file with BSD style filenames.
+
+package ar
+
+import (
+	"fmt"
+)
+
+type Error interface {
+	error
+	Fatal() bool // Is the error fatal and the archive is now corrupted?
+}
+
+// Indicates an error with using the archive/ar API.
+type UsageError struct {

[M-A Ruel, 2016/06/14 14:30:43]

same comments as in writer.go

+	msg string
+}
+
+func (e *UsageError) Error() string {
+	return fmt.Sprintf("archive/ar: usage error, %s", e.msg)
+}
+func (e *UsageError) Fatal() bool {
+	return false
+}
+
+// Indicates an error with IO while using the archive/ar. This is always fatal.
+// IOError indicates an error occurred during IO operations.
+// IOError is always fatal.
+type IOError struct {
+	section string
+	err     error
+}
+
+func (e *IOError) Error() string {
+	return fmt.Sprintf("archive/ar: io error (%s) during %s -- *archive corrupted*", e.err.Error(), e.section)
+}
+
+func (e *IOError) Fatal() bool {
+	return true
+}