status-go/vendor/github.com/pion/webrtc/v3/internal/fmtp/fmtp.go

113 lines
2.3 KiB
Go

// SPDX-FileCopyrightText: 2023 The Pion community <https://pion.ly>
// SPDX-License-Identifier: MIT
// Package fmtp implements per codec parsing of fmtp lines
package fmtp
import (
"strings"
)
func parseParameters(line string) map[string]string {
parameters := make(map[string]string)
for _, p := range strings.Split(line, ";") {
pp := strings.SplitN(strings.TrimSpace(p), "=", 2)
key := strings.ToLower(pp[0])
var value string
if len(pp) > 1 {
value = pp[1]
}
parameters[key] = value
}
return parameters
}
// FMTP interface for implementing custom
// FMTP parsers based on MimeType
type FMTP interface {
// MimeType returns the MimeType associated with
// the fmtp
MimeType() string
// Match compares two fmtp descriptions for
// compatibility based on the MimeType
Match(f FMTP) bool
// Parameter returns a value for the associated key
// if contained in the parsed fmtp string
Parameter(key string) (string, bool)
}
// Parse parses an fmtp string based on the MimeType
func Parse(mimeType, line string) FMTP {
var f FMTP
parameters := parseParameters(line)
switch {
case strings.EqualFold(mimeType, "video/h264"):
f = &h264FMTP{
parameters: parameters,
}
case strings.EqualFold(mimeType, "video/vp9"):
f = &vp9FMTP{
parameters: parameters,
}
case strings.EqualFold(mimeType, "video/av1"):
f = &av1FMTP{
parameters: parameters,
}
default:
f = &genericFMTP{
mimeType: mimeType,
parameters: parameters,
}
}
return f
}
type genericFMTP struct {
mimeType string
parameters map[string]string
}
func (g *genericFMTP) MimeType() string {
return g.mimeType
}
// Match returns true if g and b are compatible fmtp descriptions
// The generic implementation is used for MimeTypes that are not defined
func (g *genericFMTP) Match(b FMTP) bool {
c, ok := b.(*genericFMTP)
if !ok {
return false
}
if !strings.EqualFold(g.mimeType, c.MimeType()) {
return false
}
for k, v := range g.parameters {
if vb, ok := c.parameters[k]; ok && !strings.EqualFold(vb, v) {
return false
}
}
for k, v := range c.parameters {
if va, ok := g.parameters[k]; ok && !strings.EqualFold(va, v) {
return false
}
}
return true
}
func (g *genericFMTP) Parameter(key string) (string, bool) {
v, ok := g.parameters[key]
return v, ok
}