zenoh_codec/network/
interest.rs

1//
2// Copyright (c) 2022 ZettaScale Technology
3//
4// This program and the accompanying materials are made available under the
5// terms of the Eclipse Public License 2.0 which is available at
6// http://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
7// which is available at https://www.apache.org/licenses/LICENSE-2.0.
8//
9// SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
10//
11// Contributors:
12//   ZettaScale Zenoh Team, <zenoh@zettascale.tech>
13//
14use zenoh_buffers::{
15    reader::{DidntRead, Reader},
16    writer::{DidntWrite, Writer},
17};
18use zenoh_protocol::{
19    common::{
20        iext,
21        imsg::{self, HEADER_BITS},
22    },
23    core::WireExpr,
24    network::{
25        declare, id,
26        interest::{self, Interest, InterestMode, InterestOptions},
27        Mapping,
28    },
29};
30
31use crate::{common::extension, RCodec, WCodec, Zenoh080, Zenoh080Condition, Zenoh080Header};
32
33// Interest
34impl<W> WCodec<&Interest, &mut W> for Zenoh080
35where
36    W: Writer,
37{
38    type Output = Result<(), DidntWrite>;
39
40    fn write(self, writer: &mut W, x: &Interest) -> Self::Output {
41        let Interest {
42            id,
43            mode,
44            options: _, // Compute the options on-the-fly according to Interest fields
45            wire_expr,
46            ext_qos,
47            ext_tstamp,
48            ext_nodeid,
49        } = x;
50
51        // Header
52        let mut header = id::INTEREST;
53        header |= match mode {
54            InterestMode::Final => 0b00,
55            InterestMode::Current => 0b01,
56            InterestMode::Future => 0b10,
57            InterestMode::CurrentFuture => 0b11,
58        } << HEADER_BITS;
59        let mut n_exts = ((ext_qos != &declare::ext::QoSType::DEFAULT) as u8)
60            + (ext_tstamp.is_some() as u8)
61            + ((ext_nodeid != &declare::ext::NodeIdType::DEFAULT) as u8);
62        if n_exts != 0 {
63            header |= declare::flag::Z;
64        }
65        self.write(&mut *writer, header)?;
66
67        self.write(&mut *writer, id)?;
68
69        if *mode != InterestMode::Final {
70            self.write(&mut *writer, x.options())?;
71            if let Some(we) = wire_expr.as_ref() {
72                self.write(&mut *writer, we)?;
73            }
74        }
75
76        // Extensions
77        if ext_qos != &declare::ext::QoSType::DEFAULT {
78            n_exts -= 1;
79            self.write(&mut *writer, (*ext_qos, n_exts != 0))?;
80        }
81        if let Some(ts) = ext_tstamp.as_ref() {
82            n_exts -= 1;
83            self.write(&mut *writer, (ts, n_exts != 0))?;
84        }
85        if ext_nodeid != &declare::ext::NodeIdType::DEFAULT {
86            n_exts -= 1;
87            self.write(&mut *writer, (*ext_nodeid, n_exts != 0))?;
88        }
89
90        Ok(())
91    }
92}
93
94impl<R> RCodec<Interest, &mut R> for Zenoh080
95where
96    R: Reader,
97{
98    type Error = DidntRead;
99
100    fn read(self, reader: &mut R) -> Result<Interest, Self::Error> {
101        let header: u8 = self.read(&mut *reader)?;
102        let codec = Zenoh080Header::new(header);
103
104        codec.read(reader)
105    }
106}
107
108impl<R> RCodec<Interest, &mut R> for Zenoh080Header
109where
110    R: Reader,
111{
112    type Error = DidntRead;
113
114    fn read(self, reader: &mut R) -> Result<Interest, Self::Error> {
115        if imsg::mid(self.header) != id::INTEREST {
116            return Err(DidntRead);
117        }
118
119        let id = self.codec.read(&mut *reader)?;
120        let mode = match (self.header >> HEADER_BITS) & 0b11 {
121            0b00 => InterestMode::Final,
122            0b01 => InterestMode::Current,
123            0b10 => InterestMode::Future,
124            0b11 => InterestMode::CurrentFuture,
125            _ => return Err(DidntRead),
126        };
127
128        let mut options = InterestOptions::empty();
129        let mut wire_expr = None;
130        if mode != InterestMode::Final {
131            let options_byte: u8 = self.codec.read(&mut *reader)?;
132            options = InterestOptions::from(options_byte);
133            if options.restricted() {
134                let ccond = Zenoh080Condition::new(options.named());
135                let mut we: WireExpr<'static> = ccond.read(&mut *reader)?;
136                we.mapping = if options.mapping() {
137                    Mapping::Sender
138                } else {
139                    Mapping::Receiver
140                };
141                wire_expr = Some(we);
142            }
143        }
144
145        // Extensions
146        let mut ext_qos = declare::ext::QoSType::DEFAULT;
147        let mut ext_tstamp = None;
148        let mut ext_nodeid = declare::ext::NodeIdType::DEFAULT;
149
150        let mut has_ext = imsg::has_flag(self.header, declare::flag::Z);
151        while has_ext {
152            let ext: u8 = self.codec.read(&mut *reader)?;
153            let eodec = Zenoh080Header::new(ext);
154            match iext::eid(ext) {
155                declare::ext::QoS::ID => {
156                    let (q, ext): (interest::ext::QoSType, bool) = eodec.read(&mut *reader)?;
157                    ext_qos = q;
158                    has_ext = ext;
159                }
160                declare::ext::Timestamp::ID => {
161                    let (t, ext): (interest::ext::TimestampType, bool) =
162                        eodec.read(&mut *reader)?;
163                    ext_tstamp = Some(t);
164                    has_ext = ext;
165                }
166                declare::ext::NodeId::ID => {
167                    let (nid, ext): (interest::ext::NodeIdType, bool) = eodec.read(&mut *reader)?;
168                    ext_nodeid = nid;
169                    has_ext = ext;
170                }
171                _ => {
172                    has_ext = extension::skip(reader, "Declare", ext)?;
173                }
174            }
175        }
176
177        Ok(Interest {
178            id,
179            mode,
180            options,
181            wire_expr,
182            ext_qos,
183            ext_tstamp,
184            ext_nodeid,
185        })
186    }
187}
zenoh_codec/network/interest.rs

zenoh_codec/network/
interest.rs
