compress/gzip: clarify Latin-1 restrictions on gzip.Header
Fixes #12361.
Change-Id: Ifd62e8d93b2d733e67e0186c7185cd6291d3bbc1
Reviewed-on: https://go-review.googlesource.com/13939
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/src/compress/gzip/gunzip.go b/src/compress/gzip/gunzip.go
index 72ee55c..dc27653 100644
--- a/src/compress/gzip/gunzip.go
+++ b/src/compress/gzip/gunzip.go
@@ -43,6 +43,9 @@
// The gzip file stores a header giving metadata about the compressed file.
// That header is exposed as the fields of the Writer and Reader structs.
+//
+// Strings must be UTF-8 encoded and may only contain Unicode code points
+// U+0001 through U+00FF, due to limitations of the GZIP file format.
type Header struct {
Comment string // comment
Extra []byte // "extra data"
diff --git a/src/compress/gzip/gzip.go b/src/compress/gzip/gzip.go
index 5131d12..8c76144 100644
--- a/src/compress/gzip/gzip.go
+++ b/src/compress/gzip/gzip.go
@@ -44,10 +44,7 @@
// Writes may be buffered and not flushed until Close.
//
// Callers that wish to set the fields in Writer.Header must do so before
-// the first call to Write or Close. The Comment and Name header fields are
-// UTF-8 strings in Go, but the underlying format requires NUL-terminated ISO
-// 8859-1 (Latin-1). NUL or non-Latin-1 runes in those strings will lead to an
-// error on Write.
+// the first call to Write, Flush, or Close.
func NewWriter(w io.Writer) *Writer {
z, _ := NewWriterLevel(w, DefaultCompression)
return z
