streaming

commit 96a874b067dad9a5704171d9c63a5594b6d42e3d
parent 8d2c4bc42dfbbe01d8d7cfd968ca60c8048ae6f9
Author: Oliver Lowe <o@olowe.co>
Date:   Sat, 10 Aug 2024 18:56:32 +1000

sdp: resolve remaining validation, documentation TODOs

No real changes, just notes. Always encode a valid timestamp when
session start time is unset but an end time is set. Document the TTL
in ConnInfo is a specific property of multicast traffic. No need to
impose more structure on session Attributes when the data is pretty
free-form anyway (similar to http.Header). Safely round times in
session repeat schedules to ensure we never write invalid decimal
places.

Diffstat:
M
sdp/encode.go
 | 
1
-
M
sdp/parser.go
 | 
1
-
M
sdp/sdp.go
 | 
10
+++++-----
M
sdp/time.go
 | 
6
++++--

4 files changed, 9 insertions(+), 9 deletions(-)
diff --git a/sdp/encode.go b/sdp/encode.go
@@ -39,7 +39,6 @@ func (s Session) String() string {
 		fmt.Fprintln(buf, s.Bandwidth)
 	}
 
-	// TODO(otl): what about the invalid case where Time[0] is zero but Time[1] is not?
 	if s.Time[0].IsZero() {
 		fmt.Fprintln(buf, "t=0 0")
 	} else {
diff --git a/sdp/parser.go b/sdp/parser.go
@@ -12,7 +12,6 @@ type parser struct {
 	*bufio.Scanner
 	err error
 	// Field name and value from the current line.
-	// TODO(otl): rename? key, value is very non-specific...
 	key, value string
 	next       []string // expected next field names
 
diff --git a/sdp/sdp.go b/sdp/sdp.go
@@ -141,7 +141,6 @@ func parseBandwidth(s string) (Bandwidth, error) {
 	if !ok {
 		return Bandwidth{}, fmt.Errorf("missing %s separator", ":")
 	}
-	// TODO(otl): check bandwith type is actually one specified in section 5.8.
 	if t == "" {
 		return Bandwidth{}, fmt.Errorf("missing bandwidth type")
 	}
@@ -170,7 +169,6 @@ type Media struct {
 	Title      string
 	Connection *ConnInfo
 	Bandwidth  *Bandwidth
-	// TODO(otl): store as k, v pairs
 	Attributes []string
 }
 
@@ -311,9 +309,11 @@ func parseMedia(s string) (Media, error) {
 // ConnInfo represents connection information.
 type ConnInfo struct {
 	Address netip.Addr
-	// TODO(otl): what are these units? seconds?
-	TTL   uint8 // time to live
-	Count int   // number of addresses after Address
+	// TTL is the time-to-live of multicast packets.
+	TTL uint8
+	// Count is the number of subsequent IP addresses after
+	// Address used in the session.
+	Count int
 }
 
 func (c *ConnInfo) String() string {
diff --git a/sdp/time.go b/sdp/time.go
@@ -3,6 +3,7 @@ package sdp
 import (
 	"errors"
 	"fmt"
+	"math"
 	"strconv"
 	"strings"
 	"time"
@@ -44,8 +45,9 @@ type Repeat struct {
 }
 
 func (rp *Repeat) String() string {
-	// TODO(otl): print with no decimal places?
-	s := fmt.Sprintf("r=%f %f ", rp.Interval.Round(time.Second).Seconds(), rp.Active.Round(time.Second).Seconds())
+	interval := math.Round(rp.Interval.Round(time.Second).Seconds())
+	active := math.Round(rp.Active.Round(time.Second).Seconds())
+	s := fmt.Sprintf("r=%d %d ", int(interval), int(active))
 	if len(rp.Offsets) > 0 {
 		ss := make([]string, len(rp.Offsets))
 		for i := range rp.Offsets {