cleanup code

README.md

@@ -13,7 +13,7 @@ Features:
 * Publish multiple streams at once, each in a separate path, that can be read by multiple users
 * Each stream can have multiple video and audio tracks
 * Supports the RTP/RTCP streaming protocol
-* Optional authentication schema for publishers
+* Optional publisher authentication
 * Compatible with Linux and Windows, does not require any dependency or interpreter, it's a single executable
 
 

client.go

@@ -1,7 +1,6 @@
 package main
 
 import (
-	"errors"
 	"fmt"
 	"io"
 	"log"
@@ -15,13 +14,6 @@ import (
 	"gortc.io/sdp"
 )
 
-var (
-	errTeardown = errors.New("teardown")
-	errPlay     = errors.New("play")
-	errRecord   = errors.New("record")
-	errWrongKey = errors.New("wrong key")
-)
-
 func interleavedChannelToTrack(channel int) (int, trackFlow) {
 	if (channel % 2) == 0 {
 		return (channel / 2), _TRACK_FLOW_RTP
@@ -158,152 +150,49 @@ func (c *client) run() {
 			return
 		}
 
-		c.log(req.Method)
-
-		res, err := c.handleRequest(req)
-
-		switch err {
-		// normal response
-		case nil:
-			err = c.rconn.WriteResponse(res)
-			if err != nil {
-				c.log("ERR: %s", err)
-				return
-			}
-
-		// TEARDOWN: close connection silently
-		case errTeardown:
+		ok := c.handleRequest(req)
+		if !ok {
 			return
+		}
+	}
+}
 
-		// PLAY: first write response, then set state
-		// otherwise, in case of TCP connections, RTP packets could be written
-		// before the response
-		// then switch to RTP if TCP
-		case errPlay:
-			err = c.rconn.WriteResponse(res)
-			if err != nil {
-				c.log("ERR: %s", err)
-				return
-			}
-
-			c.log("is receiving on path %s, %d %s via %s", c.path, len(c.streamTracks), func() string {
-				if len(c.streamTracks) == 1 {
-					return "track"
-				}
-				return "tracks"
-			}(), c.streamProtocol)
-
-			c.p.mutex.Lock()
-			c.state = "PLAY"
-			c.p.mutex.Unlock()
-
-			// when protocol is TCP, the RTSP connection becomes a RTP connection
-			// receive RTP feedback, do not parse it, wait until connection closes
-			if c.streamProtocol == _STREAM_PROTOCOL_TCP {
-				buf := make([]byte, 2048)
-				for {
-					_, err := c.rconn.Read(buf)
-					if err != nil {
-						if err != io.EOF {
-							c.log("ERR: %s", err)
-						}
-						return
-					}
-				}
-			}
-
-		// RECORD: switch to RTP if TCP
-		case errRecord:
-			err = c.rconn.WriteResponse(res)
-			if err != nil {
-				c.log("ERR: %s", err)
-				return
-			}
-
-			c.p.mutex.Lock()
-			c.state = "RECORD"
-			c.p.mutex.Unlock()
-
-			c.log("is publishing on path %s, %d %s via %s", c.path, len(c.streamTracks), func() string {
-				if len(c.streamTracks) == 1 {
-					return "track"
-				}
-				return "tracks"
-			}(), c.streamProtocol)
-
-			// when protocol is TCP, the RTSP connection becomes a RTP connection
-			// receive RTP data and parse it
-			if c.streamProtocol == _STREAM_PROTOCOL_TCP {
-				buf := make([]byte, 2048)
-				for {
-					channel, n, err := c.rconn.ReadInterleavedFrame(buf)
-					if err != nil {
-						if _, ok := err.(*net.OpError); ok {
-						} else if err == io.EOF {
-						} else {
-							c.log("ERR: %s", err)
-						}
-						return
-					}
-
-					trackId, trackFlow := interleavedChannelToTrack(channel)
-
-					if trackId >= len(c.streamTracks) {
-						c.log("ERR: invalid track id '%d'", trackId)
-						return
-					}
-
-					c.p.mutex.RLock()
-					c.p.forwardTrack(c.path, trackId, trackFlow, buf[:n])
-					c.p.mutex.RUnlock()
-				}
-			}
-
-		// wrong key: reply with 401 and exit
-		case errWrongKey:
-			c.log("ERR: %s", err)
-
-			c.rconn.WriteResponse(&rtsp.Response{
-				StatusCode: 401,
-				Status:     "Unauthorized",
-				Headers: map[string]string{
-					"CSeq": req.Headers["CSeq"],
-				},
-			})
-			return
+func (c *client) writeRes(res *rtsp.Response) {
+	c.rconn.WriteResponse(res)
+}
 
-		// generic error: reply with code 400 and exit
-		default:
-			c.log("ERR: %s", err)
+func (c *client) writeResError(req *rtsp.Request, err error) {
+	c.log("ERR: %s", err)
 
-			if cseq, ok := req.Headers["CSeq"]; ok {
-				c.rconn.WriteResponse(&rtsp.Response{
-					StatusCode: 400,
-					Status:     "Bad Request",
-					Headers: map[string]string{
-						"CSeq": cseq,
-					},
-				})
-			} else {
-				c.rconn.WriteResponse(&rtsp.Response{
-					StatusCode: 400,
-					Status:     "Bad Request",
-				})
-			}
-			return
-		}
+	if cseq, ok := req.Headers["CSeq"]; ok {
+		c.rconn.WriteResponse(&rtsp.Response{
+			StatusCode: 400,
+			Status:     "Bad Request",
+			Headers: map[string]string{
+				"CSeq": cseq,
+			},
+		})
+	} else {
+		c.rconn.WriteResponse(&rtsp.Response{
+			StatusCode: 400,
+			Status:     "Bad Request",
+		})
 	}
 }
 
-func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
+func (c *client) handleRequest(req *rtsp.Request) bool {
+	c.log(req.Method)
+
 	cseq, ok := req.Headers["CSeq"]
 	if !ok {
-		return nil, fmt.Errorf("cseq missing")
+		c.writeResError(req, fmt.Errorf("cseq missing"))
+		return false
 	}
 
 	ur, err := url.Parse(req.Url)
 	if err != nil {
-		return nil, fmt.Errorf("unable to parse path '%s'", req.Url)
+		c.writeResError(req, fmt.Errorf("unable to parse path '%s'", req.Url))
+		return false
 	}
 
 	path := func() string {
@@ -327,7 +216,7 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 		// do not check state, since OPTIONS can be requested
 		// in any state
 
-		return &rtsp.Response{
+		c.writeRes(&rtsp.Response{
 			StatusCode: 200,
 			Status:     "OK",
 			Headers: map[string]string{
@@ -342,11 +231,13 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 					"TEARDOWN",
 				}, ", "),
 			},
-		}, nil
+		})
+		return true
 
 	case "DESCRIBE":
 		if c.state != "STARTING" {
-			return nil, fmt.Errorf("client is in state '%s'", c.state)
+			c.writeResError(req, fmt.Errorf("client is in state '%s'", c.state))
+			return false
 		}
 
 		sdp, err := func() ([]byte, error) {
@@ -361,10 +252,11 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 			return pub.streamSdpText, nil
 		}()
 		if err != nil {
-			return nil, err
+			c.writeResError(req, err)
+			return false
 		}
 
-		return &rtsp.Response{
+		c.writeRes(&rtsp.Response{
 			StatusCode: 200,
 			Status:     "OK",
 			Headers: map[string]string{
@@ -373,20 +265,24 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 				"Content-Type": "application/sdp",
 			},
 			Content: sdp,
-		}, nil
+		})
+		return true
 
 	case "ANNOUNCE":
 		if c.state != "STARTING" {
-			return nil, fmt.Errorf("client is in state '%s'", c.state)
+			c.writeResError(req, fmt.Errorf("client is in state '%s'", c.state))
+			return false
 		}
 
 		ct, ok := req.Headers["Content-Type"]
 		if !ok {
-			return nil, fmt.Errorf("Content-Type header missing")
+			c.writeResError(req, fmt.Errorf("Content-Type header missing"))
+			return false
 		}
 
 		if ct != "application/sdp" {
-			return nil, fmt.Errorf("unsupported Content-Type '%s'", ct)
+			c.writeResError(req, fmt.Errorf("unsupported Content-Type '%s'", ct))
+			return false
 		}
 
 		sdpParsed, err := func() (*sdp.Message, error) {
@@ -405,22 +301,33 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 			return m, nil
 		}()
 		if err != nil {
-			return nil, fmt.Errorf("invalid SDP: %s", err)
+			c.writeResError(req, fmt.Errorf("invalid SDP: %s", err))
+			return false
 		}
 
 		if c.p.publishKey != "" {
 			q, err := url.ParseQuery(ur.RawQuery)
 			if err != nil {
-				return nil, fmt.Errorf("unable to parse query")
+				c.writeResError(req, fmt.Errorf("unable to parse query"))
+				return false
 			}
 
 			key, ok := q["key"]
 			if !ok || len(key) == 0 {
-				return nil, fmt.Errorf("key missing")
+				c.writeResError(req, fmt.Errorf("key missing"))
+				return false
 			}
 
 			if key[0] != c.p.publishKey {
-				return nil, errWrongKey
+				// reply with 401 and exit
+				c.writeRes(&rtsp.Response{
+					StatusCode: 401,
+					Status:     "Unauthorized",
+					Headers: map[string]string{
+						"CSeq": req.Headers["CSeq"],
+					},
+				})
+				return false
 			}
 		}
 
@@ -441,27 +348,31 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 			return nil
 		}()
 		if err != nil {
-			return nil, err
+			c.writeResError(req, err)
+			return false
 		}
 
-		return &rtsp.Response{
+		c.writeRes(&rtsp.Response{
 			StatusCode: 200,
 			Status:     "OK",
 			Headers: map[string]string{
 				"CSeq": cseq,
 			},
-		}, nil
+		})
+		return true
 
 	case "SETUP":
 		transportstr, ok := req.Headers["Transport"]
 		if !ok {
-			return nil, fmt.Errorf("transport header missing")
+			c.writeResError(req, fmt.Errorf("transport header missing"))
+			return false
 		}
 
 		th := newTransportHeader(transportstr)
 
 		if _, ok := th["unicast"]; !ok {
-			return nil, fmt.Errorf("transport header does not contain unicast")
+			c.writeResError(req, fmt.Errorf("transport header does not contain unicast"))
+			return false
 		}
 
 		switch c.state {
@@ -471,11 +382,13 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 			if _, ok := th["RTP/AVP"]; ok {
 				rtpPort, rtcpPort := th.getClientPorts()
 				if rtpPort == 0 || rtcpPort == 0 {
-					return nil, fmt.Errorf("transport header does not have valid client ports (%s)", transportstr)
+					c.writeResError(req, fmt.Errorf("transport header does not have valid client ports (%s)", transportstr))
+					return false
 				}
 
 				if c.path != "" && path != c.path {
-					return nil, fmt.Errorf("path has changed")
+					c.writeResError(req, fmt.Errorf("path has changed"))
+					return false
 				}
 
 				err = func() error {
@@ -506,10 +419,11 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 					return nil
 				}()
 				if err != nil {
-					return nil, err
+					c.writeResError(req, err)
+					return false
 				}
 
-				return &rtsp.Response{
+				c.writeRes(&rtsp.Response{
 					StatusCode: 200,
 					Status:     "OK",
 					Headers: map[string]string{
@@ -523,12 +437,14 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 						}, ";"),
 						"Session": "12345678",
 					},
-				}, nil
+				})
+				return true
 
 				// play via TCP
 			} else if _, ok := th["RTP/AVP/TCP"]; ok {
 				if c.path != "" && path != c.path {
-					return nil, fmt.Errorf("path has changed")
+					c.writeResError(req, fmt.Errorf("path has changed"))
+					return false
 				}
 
 				err = func() error {
@@ -559,12 +475,13 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 					return nil
 				}()
 				if err != nil {
-					return nil, err
+					c.writeResError(req, err)
+					return false
 				}
 
 				interleaved := fmt.Sprintf("%d-%d", ((len(c.streamTracks) - 1) * 2), ((len(c.streamTracks)-1)*2)+1)
 
-				return &rtsp.Response{
+				c.writeRes(&rtsp.Response{
 					StatusCode: 200,
 					Status:     "OK",
 					Headers: map[string]string{
@@ -576,27 +493,32 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 						}, ";"),
 						"Session": "12345678",
 					},
-				}, nil
+				})
+				return true
 
 			} else {
-				return nil, fmt.Errorf("transport header does not contain a valid protocol (RTP/AVP or RTP/AVP/TCP) (%s)", transportstr)
+				c.writeResError(req, fmt.Errorf("transport header does not contain a valid protocol (RTP/AVP or RTP/AVP/TCP) (%s)", transportstr))
+				return false
 			}
 
 		// record
 		case "ANNOUNCE", "PRE_RECORD":
 			if _, ok := th["mode=record"]; !ok {
-				return nil, fmt.Errorf("transport header does not contain mode=record")
+				c.writeResError(req, fmt.Errorf("transport header does not contain mode=record"))
+				return false
 			}
 
 			if path != c.path {
-				return nil, fmt.Errorf("path has changed")
+				c.writeResError(req, fmt.Errorf("path has changed"))
+				return false
 			}
 
 			// record via UDP
 			if _, ok := th["RTP/AVP/UDP"]; ok {
 				rtpPort, rtcpPort := th.getClientPorts()
 				if rtpPort == 0 || rtcpPort == 0 {
-					return nil, fmt.Errorf("transport header does not have valid client ports (%s)", transportstr)
+					c.writeResError(req, fmt.Errorf("transport header does not have valid client ports (%s)", transportstr))
+					return false
 				}
 
 				err = func() error {
@@ -621,10 +543,11 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 					return nil
 				}()
 				if err != nil {
-					return nil, err
+					c.writeResError(req, err)
+					return false
 				}
 
-				return &rtsp.Response{
+				c.writeRes(&rtsp.Response{
 					StatusCode: 200,
 					Status:     "OK",
 					Headers: map[string]string{
@@ -638,7 +561,8 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 						}, ";"),
 						"Session": "12345678",
 					},
-				}, nil
+				})
+				return true
 
 				// record via TCP
 			} else if _, ok := th["RTP/AVP/TCP"]; ok {
@@ -675,10 +599,11 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 					return nil
 				}()
 				if err != nil {
-					return nil, err
+					c.writeResError(req, err)
+					return false
 				}
 
-				return &rtsp.Response{
+				c.writeRes(&rtsp.Response{
 					StatusCode: 200,
 					Status:     "OK",
 					Headers: map[string]string{
@@ -690,23 +615,28 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 						}, ";"),
 						"Session": "12345678",
 					},
-				}, nil
+				})
+				return true
 
 			} else {
-				return nil, fmt.Errorf("transport header does not contain a valid protocol (RTP/AVP or RTP/AVP/TCP) (%s)", transportstr)
+				c.writeResError(req, fmt.Errorf("transport header does not contain a valid protocol (RTP/AVP or RTP/AVP/TCP) (%s)", transportstr))
+				return false
 			}
 
 		default:
-			return nil, fmt.Errorf("client is in state '%s'", c.state)
+			c.writeResError(req, fmt.Errorf("client is in state '%s'", c.state))
+			return false
 		}
 
 	case "PLAY":
 		if c.state != "PRE_PLAY" {
-			return nil, fmt.Errorf("client is in state '%s'", c.state)
+			c.writeResError(req, fmt.Errorf("client is in state '%s'", c.state))
+			return false
 		}
 
 		if path != c.path {
-			return nil, fmt.Errorf("path has changed")
+			c.writeResError(req, fmt.Errorf("path has changed"))
+			return false
 		}
 
 		err := func() error {
@@ -725,25 +655,59 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 			return nil
 		}()
 		if err != nil {
-			return nil, err
+			c.writeResError(req, err)
+			return false
 		}
 
-		return &rtsp.Response{
+		// first write response, then set state
+		// otherwise, in case of TCP connections, RTP packets could be written
+		// before the response
+		c.writeRes(&rtsp.Response{
 			StatusCode: 200,
 			Status:     "OK",
 			Headers: map[string]string{
 				"CSeq":    cseq,
 				"Session": "12345678",
 			},
-		}, errPlay
+		})
+
+		c.log("is receiving on path '%s', %d %s via %s", c.path, len(c.streamTracks), func() string {
+			if len(c.streamTracks) == 1 {
+				return "track"
+			}
+			return "tracks"
+		}(), c.streamProtocol)
+
+		c.p.mutex.Lock()
+		c.state = "PLAY"
+		c.p.mutex.Unlock()
+
+		// when protocol is TCP, the RTSP connection becomes a RTP connection
+		// receive RTP feedback, do not parse it, wait until connection closes
+		if c.streamProtocol == _STREAM_PROTOCOL_TCP {
+			buf := make([]byte, 2048)
+			for {
+				_, err := c.rconn.Read(buf)
+				if err != nil {
+					if err != io.EOF {
+						c.log("ERR: %s", err)
+					}
+					return false
+				}
+			}
+		}
+
+		return true
 
 	case "PAUSE":
 		if c.state != "PLAY" {
-			return nil, fmt.Errorf("client is in state '%s'", c.state)
+			c.writeResError(req, fmt.Errorf("client is in state '%s'", c.state))
+			return false
 		}
 
 		if path != c.path {
-			return nil, fmt.Errorf("path has changed")
+			c.writeResError(req, fmt.Errorf("path has changed"))
+			return false
 		}
 
 		c.log("paused")
@@ -752,22 +716,25 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 		c.state = "PRE_PLAY"
 		c.p.mutex.Unlock()
 
-		return &rtsp.Response{
+		c.writeRes(&rtsp.Response{
 			StatusCode: 200,
 			Status:     "OK",
 			Headers: map[string]string{
 				"CSeq":    cseq,
 				"Session": "12345678",
 			},
-		}, nil
+		})
+		return true
 
 	case "RECORD":
 		if c.state != "PRE_RECORD" {
-			return nil, fmt.Errorf("client is in state '%s'", c.state)
+			c.writeResError(req, fmt.Errorf("client is in state '%s'", c.state))
+			return false
 		}
 
 		if path != c.path {
-			return nil, fmt.Errorf("path has changed")
+			c.writeResError(req, fmt.Errorf("path has changed"))
+			return false
 		}
 
 		err := func() error {
@@ -781,22 +748,66 @@ func (c *client) handleRequest(req *rtsp.Request) (*rtsp.Response, error) {
 			return nil
 		}()
 		if err != nil {
-			return nil, err
+			c.writeResError(req, err)
+			return false
 		}
 
-		return &rtsp.Response{
+		c.writeRes(&rtsp.Response{
 			StatusCode: 200,
 			Status:     "OK",
 			Headers: map[string]string{
 				"CSeq":    cseq,
 				"Session": "12345678",
 			},
-		}, errRecord
+		})
+
+		c.p.mutex.Lock()
+		c.state = "RECORD"
+		c.p.mutex.Unlock()
+
+		c.log("is publishing on path '%s', %d %s via %s", c.path, len(c.streamTracks), func() string {
+			if len(c.streamTracks) == 1 {
+				return "track"
+			}
+			return "tracks"
+		}(), c.streamProtocol)
+
+		// when protocol is TCP, the RTSP connection becomes a RTP connection
+		// receive RTP data and parse it
+		if c.streamProtocol == _STREAM_PROTOCOL_TCP {
+			buf := make([]byte, 2048)
+			for {
+				channel, n, err := c.rconn.ReadInterleavedFrame(buf)
+				if err != nil {
+					if _, ok := err.(*net.OpError); ok {
+					} else if err == io.EOF {
+					} else {
+						c.log("ERR: %s", err)
+					}
+					return false
+				}
+
+				trackId, trackFlow := interleavedChannelToTrack(channel)
+
+				if trackId >= len(c.streamTracks) {
+					c.log("ERR: invalid track id '%d'", trackId)
+					return false
+				}
+
+				c.p.mutex.RLock()
+				c.p.forwardTrack(c.path, trackId, trackFlow, buf[:n])
+				c.p.mutex.RUnlock()
+			}
+		}
+
+		return true
 
 	case "TEARDOWN":
-		return nil, errTeardown
+		// close connection silently
+		return false
 
 	default:
-		return nil, fmt.Errorf("unhandled method '%s'", req.Method)
+		c.writeResError(req, fmt.Errorf("unhandled method '%s'", req.Method))
+		return false
 	}
 }