78 lines
2.0 KiB
Go
78 lines
2.0 KiB
Go
// SPDX-FileCopyrightText: 2023 The Pion community <https://pion.ly>
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// SPDX-License-Identifier: MIT
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package webrtc
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import (
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"encoding/json"
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)
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// SDPSemantics determines which style of SDP offers and answers
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// can be used
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type SDPSemantics int
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const (
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// SDPSemanticsUnifiedPlan uses unified-plan offers and answers
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// (the default in Chrome since M72)
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// https://tools.ietf.org/html/draft-roach-mmusic-unified-plan-00
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SDPSemanticsUnifiedPlan SDPSemantics = iota
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// SDPSemanticsPlanB uses plan-b offers and answers
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// NB: This format should be considered deprecated
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// https://tools.ietf.org/html/draft-uberti-rtcweb-plan-00
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SDPSemanticsPlanB
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// SDPSemanticsUnifiedPlanWithFallback prefers unified-plan
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// offers and answers, but will respond to a plan-b offer
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// with a plan-b answer
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SDPSemanticsUnifiedPlanWithFallback
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)
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const (
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sdpSemanticsUnifiedPlanWithFallback = "unified-plan-with-fallback"
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sdpSemanticsUnifiedPlan = "unified-plan"
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sdpSemanticsPlanB = "plan-b"
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)
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func newSDPSemantics(raw string) SDPSemantics {
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switch raw {
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case sdpSemanticsUnifiedPlan:
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return SDPSemanticsUnifiedPlan
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case sdpSemanticsPlanB:
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return SDPSemanticsPlanB
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case sdpSemanticsUnifiedPlanWithFallback:
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return SDPSemanticsUnifiedPlanWithFallback
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default:
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return SDPSemantics(Unknown)
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}
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}
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func (s SDPSemantics) String() string {
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switch s {
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case SDPSemanticsUnifiedPlanWithFallback:
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return sdpSemanticsUnifiedPlanWithFallback
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case SDPSemanticsUnifiedPlan:
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return sdpSemanticsUnifiedPlan
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case SDPSemanticsPlanB:
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return sdpSemanticsPlanB
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default:
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return ErrUnknownType.Error()
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}
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}
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// UnmarshalJSON parses the JSON-encoded data and stores the result
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func (s *SDPSemantics) UnmarshalJSON(b []byte) error {
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var val string
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if err := json.Unmarshal(b, &val); err != nil {
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return err
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}
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*s = newSDPSemantics(val)
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return nil
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}
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// MarshalJSON returns the JSON encoding
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func (s SDPSemantics) MarshalJSON() ([]byte, error) {
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return json.Marshal(s.String())
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}
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