Add a CGI contrib

1 files changed, 35 insertions, 0 deletions

diff --git a/gemini/response.go b/gemini/response.go
index 90340a5..478913b 100644
--- a/gemini/response.go
+++ b/gemini/response.go
@@ -1,7 +1,9 @@
 package gemini
 
 import (
+	"bufio"
 	"bytes"
+	"errors"
 	"io"
 	"strconv"
 )
@@ -262,6 +264,39 @@ func CertInvalid(msg string) *Response {
 	}
 }
 
+// InvalidResponseLineEnding indicates that a gemini response header didn't end with "\r\n".
+var InvalidResponseLineEnding = errors.New("Invalid response line ending.")
+
+// InvalidResponseHeaderLine indicates a malformed gemini response header line.
+var InvalidResponseHeaderLine = errors.New("Invalid response header line.")
+
+// ParseResponse parses a complete gemini response from a reader.
+//
+// The reader must contain only one gemini response.
+func ParseResponse(rdr io.Reader) (*Response, error) {
+	bufrdr := bufio.NewReader(rdr)
+
+	hdrLine, err := bufrdr.ReadBytes('\n')
+	if err != nil {
+		return nil, InvalidResponseLineEnding
+	}
+	if hdrLine[len(hdrLine)-2] != '\r' {
+		return nil, InvalidResponseLineEnding
+	}
+	hdrLine = hdrLine[:len(hdrLine)-2]
+
+	status, err := strconv.Atoi(string(hdrLine[:2]))
+	if err != nil {
+		return nil, InvalidResponseHeaderLine
+	}
+
+	return &Response{
+		Status: Status(status),
+		Meta:   string(hdrLine[2:]),
+		Body:   bufrdr,
+	}, nil
+}
+
 // Read implements io.Reader for Response.
 func (r *Response) Read(b []byte) (int, error) {
 	r.ensureReader()