lio 0.4.1

A platform-independent async I/O library with native support for io_uring (Linux), IOCP (Windows), and kqueue (macOS)
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134

use std::io;
use std::time::Duration;

#[cfg(linux)]
use crate::api::resource::Resource;
use crate::typed_op::TypedOp;
#[cfg(target_os = "linux")]
use std::os::fd::{FromRawFd, RawFd};

pub struct Timeout {
  duration: Duration,
  #[cfg(linux)]
  timespec: libc::timespec,
  #[cfg(target_os = "linux")]
  timer_res: Resource,
  #[cfg(all(unix, not(target_os = "linux")))]
  timer_id: u64,
}

assert_op_max_size!(Timeout);

// wtf are you doing waiting and then not waiting??

impl Timeout {
  pub(crate) fn new(duration: Duration) -> Self {
    Self::new_with_id(duration, 0)
  }

  pub(crate) fn new_with_id(
    duration: Duration,
    #[allow(unused)] id: u64,
  ) -> Self {
    #[cfg(target_os = "linux")]
    let timer_fd =
      Self::create_timer_fd(duration).expect("Failed to create timerfd");

    Self {
      duration,
      #[cfg(linux)]
      timespec: libc::timespec {
        tv_sec: duration.as_secs() as libc::time_t,
        tv_nsec: duration.subsec_nanos() as libc::c_long,
      },
      #[cfg(target_os = "linux")]
      // SAFETY: timer_fd is valid, just created by create_timer_fd above
      timer_res: unsafe { Resource::from_raw_fd(timer_fd) },
      #[cfg(kqueue)]
      timer_id: id,
    }
  }

  #[cfg(target_os = "linux")]
  fn create_timer_fd(duration: Duration) -> std::io::Result<RawFd> {
    use std::mem::MaybeUninit;

    // Create timerfd
    let fd = syscall!(timerfd_create(
      libc::CLOCK_MONOTONIC,
      libc::TFD_NONBLOCK | libc::TFD_CLOEXEC
    ))?;

    // Set the timeout
    // SAFETY: itimerspec is a C struct where all-zeros is a valid representation
    let mut new_value: libc::itimerspec =
      unsafe { MaybeUninit::zeroed().assume_init() };
    new_value.it_value.tv_sec = duration.as_secs() as libc::time_t;
    new_value.it_value.tv_nsec = duration.subsec_nanos() as libc::c_long;
    // it_interval is zero (no repeat)

    syscall!(timerfd_settime(
      fd,
      0,
      &new_value as *const libc::itimerspec,
      std::ptr::null_mut(),
    ))?;

    Ok(fd)
  }

  pub fn duration(&self) -> Duration {
    self.duration
  }

  #[cfg(kqueue)]
  pub fn timer_id(&self) -> u64 {
    self.timer_id
  }
}

impl TypedOp for Timeout {
  type Result = std::io::Result<()>;

  fn into_op(&mut self) -> crate::op::Op {
    crate::op::Op::Timeout {
      duration: self.duration,
      #[cfg(target_os = "linux")]
      timer_fd: self.timer_res.clone(),
      #[cfg(target_os = "linux")]
      timespec: &self.timespec as *const libc::timespec,
    }
  }

  fn extract_result(self, res: isize) -> Self::Result {
    if res == 0 {
      Ok(())
    } else {
      match res.abs() as i32 {
        #[cfg(target_os = "linux")]
        libc::ETIME => Ok(()),
        #[cfg(any(target_os = "freebsd", target_os = "macos"))]
        libc::ETIMEDOUT => Ok(()),
        _ => Err(io::Error::last_os_error()),
      }
    }
  }

  // #[cfg(unix)]
  // fn meta(&self) -> crate::operation::OpMeta {
  //   crate::operation::OpMeta::CAP_TIMER
  // }

  // #[cfg(unix)]
  // fn cap(&self) -> i32 {
  //   #[cfg(target_os = "linux")]
  //   return self.timer_res.as_raw_fd();
  //   #[cfg(not(target_os = "linux"))]
  //   return -1;
  // }

  // fn run_blocking(&self) -> isize {
  //   std::thread::sleep(self.duration);
  //   0
  // }
}