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tokio 1.48.0

An event-driven, non-blocking I/O platform for writing asynchronous I/O backed applications.
Documentation 
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use super::utils::cstr;
use crate::{
    fs::UringOpenOptions,
    runtime::driver::op::{CancelData, Cancellable, Completable, CqeResult, Op},
};
use io_uring::{opcode, types};
use std::{ffi::CString, io, os::fd::FromRawFd, path::Path};

#[derive(Debug)]
pub(crate) struct Open {
    /// This field will be read by the kernel during the operation, so we
    /// need to ensure it is valid for the entire duration of the operation.
    #[allow(dead_code)]
    path: CString,
}

impl Completable for Open {
    type Output = crate::fs::File;
    fn complete(self, cqe: CqeResult) -> io::Result<Self::Output> {
        let fd = cqe.result? as i32;
        let file = unsafe { crate::fs::File::from_raw_fd(fd) };
        Ok(file)
    }
}

impl Cancellable for Open {
    fn cancel(self) -> CancelData {
        CancelData::Open(self)
    }
}

impl Op<Open> {
    /// Submit a request to open a file.
    pub(crate) fn open(path: &Path, options: &UringOpenOptions) -> io::Result<Op<Open>> {
        let inner_opt = options;
        let path = cstr(path)?;

        let custom_flags = inner_opt.custom_flags;
        let flags = libc::O_CLOEXEC
            | options.access_mode()?
            | options.creation_mode()?
            | (custom_flags & !libc::O_ACCMODE);

        let open_op = opcode::OpenAt::new(types::Fd(libc::AT_FDCWD), path.as_ptr())
            .flags(flags)
            .mode(inner_opt.mode)
            .build();

        // SAFETY: Parameters are valid for the entire duration of the operation
        let op = unsafe { Op::new(open_op, Open { path }) };
        Ok(op)
    }
}