move subfolders in pkg/

pkg/base/header.go

@@ -0,0 +1,124 @@
+package base
+
+import (
+	"bufio"
+	"fmt"
+	"net/http"
+	"sort"
+	"strings"
+)
+
+const (
+	headerMaxEntryCount  = 255
+	headerMaxKeyLength   = 1024
+	headerMaxValueLength = 1024
+)
+
+func headerKeyNormalize(in string) string {
+	switch strings.ToLower(in) {
+	case "rtp-info":
+		return "RTP-INFO"
+
+	case "www-authenticate":
+		return "WWW-Authenticate"
+
+	case "cseq":
+		return "CSeq"
+	}
+	return http.CanonicalHeaderKey(in)
+}
+
+// HeaderValue is an header value.
+type HeaderValue []string
+
+// Header is a RTSP reader, present in both Requests and Responses.
+type Header map[string]HeaderValue
+
+func (h Header) read(rb *bufio.Reader) error {
+	for {
+		byt, err := rb.ReadByte()
+		if err != nil {
+			return err
+		}
+
+		if byt == '\r' {
+			err := readByteEqual(rb, '\n')
+			if err != nil {
+				return err
+			}
+
+			break
+		}
+
+		if len(h) >= headerMaxEntryCount {
+			return fmt.Errorf("headers count exceeds %d", headerMaxEntryCount)
+		}
+
+		key := string([]byte{byt})
+		byts, err := readBytesLimited(rb, ':', headerMaxKeyLength-1)
+		if err != nil {
+			return err
+		}
+		key += string(byts[:len(byts)-1])
+		key = headerKeyNormalize(key)
+
+		// https://tools.ietf.org/html/rfc2616
+		// The field value MAY be preceded by any amount of spaces
+		for {
+			byt, err := rb.ReadByte()
+			if err != nil {
+				return err
+			}
+
+			if byt != ' ' {
+				break
+			}
+		}
+		rb.UnreadByte()
+
+		byts, err = readBytesLimited(rb, '\r', headerMaxValueLength)
+		if err != nil {
+			return err
+		}
+		val := string(byts[:len(byts)-1])
+
+		if len(val) == 0 {
+			return fmt.Errorf("empty header value")
+		}
+
+		err = readByteEqual(rb, '\n')
+		if err != nil {
+			return err
+		}
+
+		h[key] = append(h[key], val)
+	}
+
+	return nil
+}
+
+func (h Header) write(wb *bufio.Writer) error {
+	// sort headers by key
+	// in order to obtain deterministic results
+	var keys []string
+	for key := range h {
+		keys = append(keys, key)
+	}
+	sort.Strings(keys)
+
+	for _, key := range keys {
+		for _, val := range h[key] {
+			_, err := wb.Write([]byte(key + ": " + val + "\r\n"))
+			if err != nil {
+				return err
+			}
+		}
+	}
+
+	_, err := wb.Write([]byte("\r\n"))
+	if err != nil {
+		return err
+	}
+
+	return nil
+}