sqlx_core/io/
buf.rs

1use std::str::from_utf8;
2
3use bytes::{Buf, Bytes};
4use memchr::memchr;
5
6use crate::error::Error;
7
8pub trait BufExt: Buf {
9    // Read a nul-terminated byte sequence
10    fn get_bytes_nul(&mut self) -> Result<Bytes, Error>;
11
12    // Read a byte sequence of the exact length
13    fn get_bytes(&mut self, len: usize) -> Bytes;
14
15    // Read a nul-terminated string
16    fn get_str_nul(&mut self) -> Result<String, Error>;
17
18    // Read a string of the exact length
19    fn get_str(&mut self, len: usize) -> Result<String, Error>;
20}
21
22impl BufExt for Bytes {
23    fn get_bytes_nul(&mut self) -> Result<Bytes, Error> {
24        let nul =
25            memchr(b'\0', self).ok_or_else(|| err_protocol!("expected NUL in byte sequence"))?;
26
27        let v = self.slice(0..nul);
28
29        self.advance(nul + 1);
30
31        Ok(v)
32    }
33
34    fn get_bytes(&mut self, len: usize) -> Bytes {
35        let v = self.slice(..len);
36        self.advance(len);
37
38        v
39    }
40
41    fn get_str_nul(&mut self) -> Result<String, Error> {
42        self.get_bytes_nul().and_then(|bytes| {
43            from_utf8(&bytes)
44                .map(ToOwned::to_owned)
45                .map_err(|err| err_protocol!("{}", err))
46        })
47    }
48
49    fn get_str(&mut self, len: usize) -> Result<String, Error> {
50        let v = from_utf8(&self[..len])
51            .map_err(|err| err_protocol!("{}", err))
52            .map(ToOwned::to_owned)?;
53
54        self.advance(len);
55
56        Ok(v)
57    }
58}