sqlx_postgres/message/
parameter_description.rs

1use smallvec::SmallVec;
2use sqlx_core::bytes::{Buf, Bytes};
3
4use crate::error::Error;
5use crate::message::{BackendMessage, BackendMessageFormat};
6use crate::types::Oid;
7
8#[derive(Debug)]
9pub struct ParameterDescription {
10    pub types: SmallVec<[Oid; 6]>,
11}
12
13impl BackendMessage for ParameterDescription {
14    const FORMAT: BackendMessageFormat = BackendMessageFormat::ParameterDescription;
15
16    fn decode_body(mut buf: Bytes) -> Result<Self, Error> {
17        // Note: this is correct, max parameters is 65535, not 32767
18        // https://github.com/launchbadge/sqlx/issues/3464
19        let cnt = buf.get_u16();
20        let mut types = SmallVec::with_capacity(cnt as usize);
21
22        for _ in 0..cnt {
23            types.push(Oid(buf.get_u32()));
24        }
25
26        Ok(Self { types })
27    }
28}
29
30#[test]
31fn test_decode_parameter_description() {
32    const DATA: &[u8] = b"\x00\x02\x00\x00\x00\x00\x00\x00\x05\x00";
33
34    let m = ParameterDescription::decode_body(DATA.into()).unwrap();
35
36    assert_eq!(m.types.len(), 2);
37    assert_eq!(m.types[0], Oid(0x0000_0000));
38    assert_eq!(m.types[1], Oid(0x0000_0500));
39}
40
41#[test]
42fn test_decode_empty_parameter_description() {
43    const DATA: &[u8] = b"\x00\x00";
44
45    let m = ParameterDescription::decode_body(DATA.into()).unwrap();
46
47    assert!(m.types.is_empty());
48}
49
50#[cfg(all(test, not(debug_assertions)))]
51#[bench]
52fn bench_decode_parameter_description(b: &mut test::Bencher) {
53    const DATA: &[u8] = b"\x00\x02\x00\x00\x00\x00\x00\x00\x05\x00";
54
55    b.iter(|| {
56        ParameterDescription::decode_body(test::black_box(Bytes::from_static(DATA))).unwrap();
57    });
58}
sqlx_postgres/message/parameter_description.rs

sqlx_postgres/message/
parameter_description.rs
