dvb_si/tables/
rst.rs

1//! Running Status Table — ETSI EN 300 468 §5.2.8.
2//!
3//! Carried on PID `0x0013` with `table_id = 0x71`. A SHORT-FORM section — there
4//! is no version/section header and no CRC. The body is a flat loop of 9-byte
5//! entries, each giving the running status of one event:
6//!
7//! ```text
8//! transport_stream_id(16) original_network_id(16) service_id(16)
9//! event_id(16) reserved_future_use(5) running_status(3)
10//! ```
11
12use super::RunningStatus;
13use crate::error::{Error, Result};
14use dvb_common::{Parse, Serialize};
15
16/// table_id for the Running Status Table.
17pub const TABLE_ID: u8 = 0x71;
18/// Well-known PID on which the RST is carried.
19pub const PID: u16 = 0x0013;
20
21const HEADER_LEN: usize = 3;
22/// Each entry is 9 bytes: tsid(2) + onid(2) + sid(2) + evid(2) + status(1).
23const ENTRY_LEN: usize = 9;
24
25/// One RST entry — the running status of a single event.
26///
27/// `running_status` is the 3-bit code from EN 300 468 Table 6: 0 undefined,
28/// 1 not running, 2 starts in a few seconds, 3 pausing, 4 running,
29/// 5 service off-air, 6–7 reserved.
30#[derive(Debug, Clone, Copy, PartialEq, Eq)]
31#[cfg_attr(feature = "serde", derive(serde::Serialize))]
32pub struct RstEntry {
33    /// Transport stream carrying the event.
34    pub transport_stream_id: u16,
35    /// Originating network.
36    pub original_network_id: u16,
37    /// Service (matches `program_number` in the PAT).
38    pub service_id: u16,
39    /// Event identifier.
40    pub event_id: u16,
41    /// 3-bit running_status code (EN 300 468 Table 6).
42    pub running_status: RunningStatus,
43}
44
45/// Running Status Table (§5.2.8, Table 10).
46#[derive(Debug, Clone, PartialEq, Eq)]
47#[cfg_attr(feature = "serde", derive(serde::Serialize))]
48pub struct RstSection {
49    /// Entries in wire order.
50    pub entries: Vec<RstEntry>,
51}
52
53impl<'a> Parse<'a> for RstSection {
54    type Error = crate::error::Error;
55
56    fn parse(bytes: &'a [u8]) -> Result<Self> {
57        if bytes.len() < HEADER_LEN {
58            return Err(Error::BufferTooShort {
59                need: HEADER_LEN,
60                have: bytes.len(),
61                what: "RstSection",
62            });
63        }
64        if bytes[0] != TABLE_ID {
65            return Err(Error::UnexpectedTableId {
66                table_id: bytes[0],
67                what: "RstSection",
68                expected: &[TABLE_ID],
69            });
70        }
71        let section_length = ((bytes[1] & 0x0F) as usize) << 8 | bytes[2] as usize;
72        let total = HEADER_LEN + section_length;
73        if bytes.len() < total {
74            return Err(Error::SectionLengthOverflow {
75                declared: section_length,
76                available: bytes.len() - HEADER_LEN,
77            });
78        }
79        if section_length % ENTRY_LEN != 0 {
80            return Err(Error::BufferTooShort {
81                need: (section_length / ENTRY_LEN + 1) * ENTRY_LEN,
82                have: section_length,
83                what: "RstSection entry alignment",
84            });
85        }
86        let mut entries = Vec::with_capacity(section_length / ENTRY_LEN);
87        let mut off = HEADER_LEN;
88        while off + ENTRY_LEN <= total {
89            entries.push(RstEntry {
90                transport_stream_id: u16::from_be_bytes([bytes[off], bytes[off + 1]]),
91                original_network_id: u16::from_be_bytes([bytes[off + 2], bytes[off + 3]]),
92                service_id: u16::from_be_bytes([bytes[off + 4], bytes[off + 5]]),
93                event_id: u16::from_be_bytes([bytes[off + 6], bytes[off + 7]]),
94                running_status: RunningStatus::from_u8(bytes[off + 8] & 0x07),
95            });
96            off += ENTRY_LEN;
97        }
98        Ok(RstSection { entries })
99    }
100}
101
102impl Serialize for RstSection {
103    type Error = crate::error::Error;
104
105    fn serialized_len(&self) -> usize {
106        HEADER_LEN + self.entries.len() * ENTRY_LEN
107    }
108
109    fn serialize_into(&self, buf: &mut [u8]) -> Result<usize> {
110        let len = self.serialized_len();
111        if buf.len() < len {
112            return Err(Error::OutputBufferTooSmall {
113                need: len,
114                have: buf.len(),
115            });
116        }
117        let section_length = (len - HEADER_LEN) as u16;
118        buf[0] = TABLE_ID;
119        // section_syntax_indicator=0 (short form), reserved_future_use=1,
120        // reserved=11, section_length high nibble.
121        buf[1] = super::SECTION_B1_FLAGS_SHORT | ((section_length >> 8) as u8 & 0x0F);
122        buf[2] = (section_length & 0xFF) as u8;
123        let mut off = HEADER_LEN;
124        for e in &self.entries {
125            buf[off..off + 2].copy_from_slice(&e.transport_stream_id.to_be_bytes());
126            buf[off + 2..off + 4].copy_from_slice(&e.original_network_id.to_be_bytes());
127            buf[off + 4..off + 6].copy_from_slice(&e.service_id.to_be_bytes());
128            buf[off + 6..off + 8].copy_from_slice(&e.event_id.to_be_bytes());
129            // reserved_future_use(5)=1, running_status(3).
130            buf[off + 8] = 0xF8 | (e.running_status.to_u8() & 0x07);
131            off += ENTRY_LEN;
132        }
133        Ok(len)
134    }
135}
136impl<'a> crate::traits::TableDef<'a> for RstSection {
137    const TABLE_ID_RANGES: &'static [(u8, u8)] = &[(TABLE_ID, TABLE_ID)];
138    const NAME: &'static str = "RUNNING_STATUS";
139}
140
141#[cfg(test)]
142mod tests {
143    use super::*;
144
145    fn build_rst(entries: &[RstEntry]) -> Vec<u8> {
146        let section_length = (entries.len() * ENTRY_LEN) as u16;
147        let mut v = vec![
148            TABLE_ID,
149            0x70 | ((section_length >> 8) as u8 & 0x0F),
150            (section_length & 0xFF) as u8,
151        ];
152        for e in entries {
153            v.extend_from_slice(&e.transport_stream_id.to_be_bytes());
154            v.extend_from_slice(&e.original_network_id.to_be_bytes());
155            v.extend_from_slice(&e.service_id.to_be_bytes());
156            v.extend_from_slice(&e.event_id.to_be_bytes());
157            v.push(0xF8 | (e.running_status.to_u8() & 0x07));
158        }
159        v
160    }
161
162    fn entry(tsid: u16, onid: u16, sid: u16, evid: u16, rs: RunningStatus) -> RstEntry {
163        RstEntry {
164            transport_stream_id: tsid,
165            original_network_id: onid,
166            service_id: sid,
167            event_id: evid,
168            running_status: rs,
169        }
170    }
171
172    #[test]
173    fn parse_empty() {
174        let rst = RstSection::parse(&build_rst(&[])).unwrap();
175        assert!(rst.entries.is_empty());
176    }
177
178    #[test]
179    fn parse_single_entry() {
180        let e = entry(0x1234, 0x0001, 0xABCD, 0x4000, RunningStatus::Running);
181        let rst = RstSection::parse(&build_rst(&[e])).unwrap();
182        assert_eq!(rst.entries.len(), 1);
183        assert_eq!(rst.entries[0], e);
184        assert_eq!(rst.entries[0].running_status, RunningStatus::Running); // running
185    }
186
187    #[test]
188    fn parse_multiple_entries() {
189        let es = [
190            entry(0x0001, 0x1000, 0x0010, 0x0100, RunningStatus::NotRunning),
191            entry(0x0002, 0x2000, 0x0020, 0x0200, RunningStatus::Running),
192            entry(0x0003, 0x3000, 0x0030, 0x0300, RunningStatus::ServiceOffAir),
193        ];
194        let rst = RstSection::parse(&build_rst(&es)).unwrap();
195        assert_eq!(rst.entries, es);
196    }
197
198    #[test]
199    fn parse_rejects_wrong_tag() {
200        let mut bytes = build_rst(&[]);
201        bytes[0] = 0x72;
202        assert!(matches!(
203            RstSection::parse(&bytes).unwrap_err(),
204            Error::UnexpectedTableId { table_id: 0x72, .. }
205        ));
206    }
207
208    #[test]
209    fn parse_rejects_short_buffer() {
210        assert!(matches!(
211            RstSection::parse(&[0x71, 0x70]).unwrap_err(),
212            Error::BufferTooShort { .. }
213        ));
214    }
215
216    #[test]
217    fn parse_rejects_non_multiple_loop() {
218        let bytes = [TABLE_ID, 0x70, 0x04, 0x00, 0x00, 0x00, 0x00];
219        assert!(matches!(
220            RstSection::parse(&bytes).unwrap_err(),
221            Error::BufferTooShort {
222                what: "RstSection entry alignment",
223                ..
224            }
225        ));
226    }
227
228    #[test]
229    fn serialize_round_trip() {
230        let es = [
231            entry(0xCAFE, 0xBEEF, 0x1234, 0x5678, RunningStatus::Running),
232            entry(0x0001, 0x0002, 0x0003, 0x0004, RunningStatus::ServiceOffAir),
233        ];
234        let rst = RstSection::parse(&build_rst(&es)).unwrap();
235        let mut buf = vec![0u8; rst.serialized_len()];
236        rst.serialize_into(&mut buf).unwrap();
237        assert_eq!(buf, build_rst(&es));
238        assert_eq!(RstSection::parse(&buf).unwrap(), rst);
239    }
240
241    #[test]
242    fn serialize_empty_round_trip() {
243        let rst = RstSection { entries: vec![] };
244        let mut buf = vec![0u8; rst.serialized_len()];
245        rst.serialize_into(&mut buf).unwrap();
246        assert_eq!(RstSection::parse(&buf).unwrap(), rst);
247    }
248
249    #[test]
250    fn table_trait_constants() {
251        assert_eq!(TABLE_ID, 0x71);
252        assert_eq!(PID, 0x0013);
253    }
254
255    #[cfg(feature = "serde")]
256    #[test]
257    fn serde_json_serializes_fields() {
258        // Serialize-only: assert the emitted JSON re-parses (serialize-stable).
259        let rst =
260            RstSection::parse(&build_rst(&[entry(1, 2, 3, 4, RunningStatus::Running)])).unwrap();
261        let j = serde_json::to_string(&rst).unwrap();
262        let v: serde_json::Value = serde_json::from_str(&j).unwrap();
263        assert_eq!(v["entries"][0]["service_id"], 3);
264    }
265}
dvb_si/tables/rst.rs

dvb_si/tables/
rst.rs
