1 files changed, 77 insertions, 0 deletions
diff --git a/src/pkg/http/chunked.go b/src/pkg/http/chunked.go
new file mode 100644
index 000000000..6c23e691f
--- /dev/null
+++ b/src/pkg/http/chunked.go
@@ -0,0 +1,77 @@
+// 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 http
+
+import (
+	"io"
+	"log"
+	"os"
+	"strconv"
+	"bufio"
+)
+
+// NewChunkedWriter returns a new writer that translates writes into HTTP
+// "chunked" format before writing them to w. Closing the returned writer
+// sends the final 0-length chunk that marks the end of the stream.
+//
+// NewChunkedWriter is not needed by normal applications. The http
+// package adds chunking automatically if handlers don't set a
+// Content-Length header. Using NewChunkedWriter inside a handler
+// would result in double chunking or chunking with a Content-Length
+// length, both of which are wrong.
+func NewChunkedWriter(w io.Writer) io.WriteCloser {
+	if _, bad := w.(*response); bad {
+		log.Printf("warning: using NewChunkedWriter in an http.Handler; expect corrupt output")
+	}
+	return &chunkedWriter{w}
+}
+
+// Writing to ChunkedWriter translates to writing in HTTP chunked Transfer
+// Encoding wire format to the underlying Wire writer.
+type chunkedWriter struct {
+	Wire io.Writer
+}
+
+// Write the contents of data as one chunk to Wire.
+// NOTE: Note that the corresponding chunk-writing procedure in Conn.Write has
+// a bug since it does not check for success of io.WriteString
+func (cw *chunkedWriter) Write(data []byte) (n int, err os.Error) {
+
+	// Don't send 0-length data. It looks like EOF for chunked encoding.
+	if len(data) == 0 {
+		return 0, nil
+	}
+
+	head := strconv.Itob(len(data), 16) + "\r\n"
+
+	if _, err = io.WriteString(cw.Wire, head); err != nil {
+		return 0, err
+	}
+	if n, err = cw.Wire.Write(data); err != nil {
+		return
+	}
+	if n != len(data) {
+		err = io.ErrShortWrite
+		return
+	}
+	_, err = io.WriteString(cw.Wire, "\r\n")
+
+	return
+}
+
+func (cw *chunkedWriter) Close() os.Error {
+	_, err := io.WriteString(cw.Wire, "0\r\n")
+	return err
+}
+
+// NewChunkedReader returns a new reader that translates the data read from r
+// out of HTTP "chunked" format before returning it. 
+// The reader returns os.EOF when the final 0-length chunk is read.
+//
+// NewChunkedReader is not needed by normal applications. The http package
+// automatically decodes chunking when reading response bodies.
+func NewChunkedReader(r *bufio.Reader) io.Reader {
+	return &chunkedReader{r: r}
+}