1 files changed, 60 insertions, 0 deletions
diff --git a/tun/errors.go b/tun/errors.go
new file mode 100644
index 0000000..e70b13c
--- /dev/null
+++ b/tun/errors.go
@@ -0,0 +1,60 @@
+package tun
+
+import (
+	"errors"
+	"fmt"
+)
+
+var (
+	// ErrTooManySegments is returned by Device.Read() when segmentation
+	// overflows the length of supplied buffers. This error should not cause
+	// reads to cease.
+	ErrTooManySegments = errors.New("too many segments")
+)
+
+type errorBatch []error
+
+// ErrorBatch takes a possibly nil or empty list of errors, and if the list is
+// non-nil returns an error type that wraps all of the errors. Expected usage is
+// to append to an []errors and coerce the set to an error using this method.
+func ErrorBatch(errs []error) error {
+	if len(errs) == 0 {
+		return nil
+	}
+	return errorBatch(errs)
+}
+
+func (e errorBatch) Error() string {
+	if len(e) == 0 {
+		return ""
+	}
+	if len(e) == 1 {
+		return e[0].Error()
+	}
+	return fmt.Sprintf("batch operation: %v (and %d more errors)", e[0], len(e)-1)
+}
+
+func (e errorBatch) Is(target error) bool {
+	for _, err := range e {
+		if errors.Is(err, target) {
+			return true
+		}
+	}
+	return false
+}
+
+func (e errorBatch) As(target interface{}) bool {
+	for _, err := range e {
+		if errors.As(err, target) {
+			return true
+		}
+	}
+	return false
+}
+
+func (e errorBatch) Unwrap() error {
+	if len(e) == 0 {
+		return nil
+	}
+	return e[0]
+}