rtp/packet/
mod.rs

1#[cfg(test)]
2mod packet_test;
3
4use std::fmt;
5
6use bytes::{Buf, BufMut, Bytes};
7use util::marshal::{Marshal, MarshalSize, Unmarshal};
8
9use crate::error::Error;
10use crate::header::*;
11
12/// Packet represents an RTP Packet
13/// NOTE: Raw is populated by Marshal/Unmarshal and should not be modified
14#[derive(Debug, Eq, PartialEq, Default, Clone)]
15pub struct Packet {
16    pub header: Header,
17    pub payload: Bytes,
18}
19
20impl fmt::Display for Packet {
21    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
22        let mut out = "RTP PACKET:\n".to_string();
23
24        out += format!("\tVersion: {}\n", self.header.version).as_str();
25        out += format!("\tMarker: {}\n", self.header.marker).as_str();
26        out += format!("\tPayload Type: {}\n", self.header.payload_type).as_str();
27        out += format!("\tSequence Number: {}\n", self.header.sequence_number).as_str();
28        out += format!("\tTimestamp: {}\n", self.header.timestamp).as_str();
29        out += format!("\tSSRC: {} ({:x})\n", self.header.ssrc, self.header.ssrc).as_str();
30        out += format!("\tPayload Length: {}\n", self.payload.len()).as_str();
31
32        write!(f, "{out}")
33    }
34}
35
36impl Unmarshal for Packet {
37    /// Unmarshal parses the passed byte slice and stores the result in the Header this method is called upon
38    fn unmarshal<B>(raw_packet: &mut B) -> Result<Self, util::Error>
39    where
40        Self: Sized,
41        B: Buf,
42    {
43        let header = Header::unmarshal(raw_packet)?;
44        let payload_len = raw_packet.remaining();
45        let payload = raw_packet.copy_to_bytes(payload_len);
46        if header.padding {
47            if payload_len > 0 {
48                let padding_len = payload[payload_len - 1] as usize;
49                if padding_len <= payload_len {
50                    Ok(Packet {
51                        header,
52                        payload: payload.slice(..payload_len - padding_len),
53                    })
54                } else {
55                    Err(Error::ErrShortPacket.into())
56                }
57            } else {
58                Err(Error::ErrShortPacket.into())
59            }
60        } else {
61            Ok(Packet { header, payload })
62        }
63    }
64}
65
66impl MarshalSize for Packet {
67    /// MarshalSize returns the size of the packet once marshaled.
68    fn marshal_size(&self) -> usize {
69        let payload_len = self.payload.len();
70        let padding_len = if self.header.padding {
71            let padding_len = get_padding(payload_len);
72            if padding_len == 0 {
73                4
74            } else {
75                padding_len
76            }
77        } else {
78            0
79        };
80        self.header.marshal_size() + payload_len + padding_len
81    }
82}
83
84impl Marshal for Packet {
85    /// MarshalTo serializes the packet and writes to the buffer.
86    fn marshal_to(&self, mut buf: &mut [u8]) -> Result<usize, util::Error> {
87        if buf.remaining_mut() < self.marshal_size() {
88            return Err(Error::ErrBufferTooSmall.into());
89        }
90
91        let n = self.header.marshal_to(buf)?;
92        buf = &mut buf[n..];
93        buf.put(&*self.payload);
94        let padding_len = if self.header.padding {
95            let mut padding_len = get_padding(self.payload.len());
96            if padding_len == 0 {
97                padding_len = 4;
98            }
99            for i in 0..padding_len {
100                if i != padding_len - 1 {
101                    buf.put_u8(0);
102                } else {
103                    buf.put_u8(padding_len as u8);
104                }
105            }
106            padding_len
107        } else {
108            0
109        };
110
111        Ok(n + self.payload.len() + padding_len)
112    }
113}
114
115/// getPadding Returns the padding required to make the length a multiple of 4
116fn get_padding(len: usize) -> usize {
117    if len % 4 == 0 {
118        0
119    } else {
120        4 - (len % 4)
121    }
122}
rtp/packet/mod.rs

rtp/packet/
mod.rs
