lio/api/ops/
read.rs

1use crate::typed_op::TypedOp;
2use crate::{BufResult, api::resource::Resource, buf::BufLike};
3
4pub struct Read<T>
5where
6  T: Send + Sync,
7{
8  res: Resource,
9  buf: Option<T>,
10}
11
12impl<T> Read<T>
13where
14  T: Send + Sync,
15{
16  /// Will return errn 22 "EINVAL" if offset < 0
17  pub(crate) fn new(res: Resource, mem: T) -> Self
18  where
19    T: BufLike,
20  {
21    Self { res, buf: Some(mem) }
22  }
23
24  pub fn to_op(mut self) -> crate::op::Op
25  where
26    T: BufLike + 'static,
27  {
28    let buffer = self.buf.take().expect("buffer already taken");
29    crate::op::Op::Read { fd: self.res, buffer: crate::op::OpBuf::new(buffer) }
30  }
31}
32
33impl<T> TypedOp for Read<T>
34where
35  T: BufLike + Send + Sync + 'static,
36{
37  type Result = BufResult<i32, T>;
38
39  fn into_op(&mut self) -> crate::op::Op {
40    let slice = self.buf.as_mut().expect("buffer not available").buf();
41    let ptr = slice.as_ptr() as *mut u8;
42    let len = slice.len();
43    crate::op::Op::Read {
44      fd: self.res.clone(),
45      buffer: crate::op::OpBuf::new(crate::op::RawBuf { ptr, len }),
46    }
47  }
48
49  fn extract_result(self, res: isize) -> Self::Result {
50    let buf = self.buf.expect("buffer not available");
51    if res < 0 {
52      // On error, return buffer unchanged
53      (Err(std::io::Error::from_raw_os_error((-res) as i32)), buf)
54    } else {
55      // On success, truncate buffer to read bytes
56      (Ok(res as i32), buf.after(res as usize))
57    }
58  }
59
60  // #[cfg(unix)]
61  // fn meta(&self) -> crate::operation::OpMeta {
62  //   crate::operation::OpMeta::CAP_FD | crate::operation::OpMeta::FD_READ
63  // }
64
65  // #[cfg(unix)]
66  // fn cap(&self) -> i32 {
67  //   self.res.as_raw_fd()
68  // }
69
70  // #[cfg(linux)]
71  // fn create_entry(&self) -> lio_uring::submission::Entry {
72  //   use std::os::fd::AsRawFd;
73  //   let buf_slice = self.buf.as_ref().unwrap().buf();
74  //   let ptr = buf_slice.as_ptr();
75  //   let len = buf_slice.len();
76  //   lio_uring::operation::Read::new(
77  //     self.res.as_raw_fd(),
78  //     ptr.cast_mut(),
79  //     len as u32,
80  //   )
81  //   .offset(-1i64 as u64)
82  //   .build()
83  // }
84
85  // fn run_blocking(&self) -> isize {
86  //   use std::os::fd::AsRawFd;
87  //   let buf_slice = self.buf.as_ref().unwrap().buf();
88  //   let ptr = buf_slice.as_ptr();
89  //   let len = buf_slice.len();
90  //   unsafe { libc::read(self.res.as_raw_fd(), ptr as *mut _, len) }
91  // }
92}
lio/api/ops/read.rs

lio/api/ops/
read.rs
