1 files changed, 41 insertions, 0 deletions
diff --git a/src/pkg/gob/error.go b/src/pkg/gob/error.go
new file mode 100644
index 000000000..b053761fb
--- /dev/null
+++ b/src/pkg/gob/error.go
@@ -0,0 +1,41 @@
+// 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 gob
+
+import (
+	"fmt"
+	"os"
+)
+
+// Errors in decoding and encoding are handled using panic and recover.
+// Panics caused by user error (that is, everything except run-time panics
+// such as "index out of bounds" errors) do not leave the file that caused
+// them, but are instead turned into plain os.Error returns.  Encoding and
+// decoding functions and methods that do not return an os.Error either use
+// panic to report an error or are guaranteed error-free.
+
+// A gobError wraps an os.Error and is used to distinguish errors (panics) generated in this package.
+type gobError struct {
+	os.Error
+}
+
+// errorf is like error but takes Printf-style arguments to construct an os.Error.
+func errorf(format string, args ...interface{}) {
+	error(fmt.Errorf(format, args...))
+}
+
+// error wraps the argument error and uses it as the argument to panic.
+func error(err os.Error) {
+	panic(gobError{Error: err})
+}
+
+// catchError is meant to be used as a deferred function to turn a panic(gobError) into a
+// plain os.Error.  It overwrites the error return of the function that deferred its call.
+func catchError(err *os.Error) {
+	if e := recover(); e != nil {
+		*err = e.(gobError).Error // Will re-panic if not one of our errors, such as a runtime error.
+	}
+	return
+}