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use std::io;
use std::os::fd::AsRawFd;
use std::sync::Arc;
use base::AsRawDescriptor;
use data_model::VolatileSlice;
use remain::sorted;
use thiserror::Error as ThisError;
use super::fd_executor;
use super::fd_executor::EpollReactor;
use super::fd_executor::RegisteredSource;
use crate::common_executor::RawExecutor;
use crate::mem::BackingMemory;
use crate::AllocateMode;
use crate::AsyncError;
use crate::AsyncResult;
use crate::MemRegion;
#[sorted]
#[derive(ThisError, Debug)]
pub enum Error {
#[error("An error occurred attempting to register a waker with the executor: {0}.")]
AddingWaker(fd_executor::Error),
#[error("An executor error occurred: {0}")]
Executor(fd_executor::Error),
#[error("An error occurred when executing fallocate synchronously: {0}")]
Fallocate(base::Error),
#[error("An error occurred when executing fdatasync synchronously: {0}")]
Fdatasync(base::Error),
#[error("An error occurred when executing fsync synchronously: {0}")]
Fsync(base::Error),
#[error("An error occurred when reading the FD: {0}.")]
Read(base::Error),
#[error("An error occurred when seeking the FD: {0}.")]
Seeking(base::Error),
#[error("An error occurred when writing the FD: {0}.")]
Write(base::Error),
}
pub type Result<T> = std::result::Result<T, Error>;
impl From<Error> for io::Error {
fn from(e: Error) -> Self {
use Error::*;
match e {
AddingWaker(e) => e.into(),
Executor(e) => e.into(),
Fallocate(e) => e.into(),
Fdatasync(e) => e.into(),
Fsync(e) => e.into(),
Read(e) => e.into(),
Seeking(e) => e.into(),
Write(e) => e.into(),
}
}
}
pub struct PollSource<F>(RegisteredSource<F>);
impl<F: AsRawDescriptor> PollSource<F> {
pub fn new(f: F, ex: &Arc<RawExecutor<EpollReactor>>) -> Result<Self> {
RegisteredSource::new(ex, f)
.map(PollSource)
.map_err(Error::Executor)
}
}
impl<F: AsRawDescriptor> PollSource<F> {
pub async fn read_to_vec(
&self,
file_offset: Option<u64>,
mut vec: Vec<u8>,
) -> AsyncResult<(usize, Vec<u8>)> {
loop {
let res = if let Some(offset) = file_offset {
unsafe {
libc::pread64(
self.0.duped_fd.as_raw_fd(),
vec.as_mut_ptr() as *mut libc::c_void,
vec.len(),
offset as libc::off64_t,
)
}
} else {
unsafe {
libc::read(
self.0.duped_fd.as_raw_fd(),
vec.as_mut_ptr() as *mut libc::c_void,
vec.len(),
)
}
};
if res >= 0 {
return Ok((res as usize, vec));
}
match base::Error::last() {
e if e.errno() == libc::EWOULDBLOCK => {
let op = self.0.wait_readable().map_err(Error::AddingWaker)?;
op.await.map_err(Error::Executor)?;
}
e => return Err(Error::Read(e).into()),
}
}
}
pub async fn read_to_mem(
&self,
file_offset: Option<u64>,
mem: Arc<dyn BackingMemory + Send + Sync>,
mem_offsets: impl IntoIterator<Item = MemRegion>,
) -> AsyncResult<usize> {
let mut iovecs = mem_offsets
.into_iter()
.filter_map(|mem_range| mem.get_volatile_slice(mem_range).ok())
.collect::<Vec<VolatileSlice>>();
loop {
let res = if let Some(offset) = file_offset {
unsafe {
libc::preadv64(
self.0.duped_fd.as_raw_fd(),
iovecs.as_mut_ptr() as *mut _,
iovecs.len() as i32,
offset as libc::off64_t,
)
}
} else {
unsafe {
libc::readv(
self.0.duped_fd.as_raw_fd(),
iovecs.as_mut_ptr() as *mut _,
iovecs.len() as i32,
)
}
};
if res >= 0 {
return Ok(res as usize);
}
match base::Error::last() {
e if e.errno() == libc::EWOULDBLOCK => {
let op = self.0.wait_readable().map_err(Error::AddingWaker)?;
op.await.map_err(Error::Executor)?;
}
e => return Err(Error::Read(e).into()),
}
}
}
pub async fn wait_readable(&self) -> AsyncResult<()> {
let op = self.0.wait_readable().map_err(Error::AddingWaker)?;
op.await.map_err(Error::Executor)?;
Ok(())
}
pub async fn write_from_vec(
&self,
file_offset: Option<u64>,
vec: Vec<u8>,
) -> AsyncResult<(usize, Vec<u8>)> {
loop {
let res = if let Some(offset) = file_offset {
unsafe {
libc::pwrite64(
self.0.duped_fd.as_raw_fd(),
vec.as_ptr() as *const libc::c_void,
vec.len(),
offset as libc::off64_t,
)
}
} else {
unsafe {
libc::write(
self.0.duped_fd.as_raw_fd(),
vec.as_ptr() as *const libc::c_void,
vec.len(),
)
}
};
if res >= 0 {
return Ok((res as usize, vec));
}
match base::Error::last() {
e if e.errno() == libc::EWOULDBLOCK => {
let op = self.0.wait_writable().map_err(Error::AddingWaker)?;
op.await.map_err(Error::Executor)?;
}
e => return Err(Error::Write(e).into()),
}
}
}
pub async fn write_from_mem(
&self,
file_offset: Option<u64>,
mem: Arc<dyn BackingMemory + Send + Sync>,
mem_offsets: impl IntoIterator<Item = MemRegion>,
) -> AsyncResult<usize> {
let iovecs = mem_offsets
.into_iter()
.map(|mem_range| mem.get_volatile_slice(mem_range))
.filter_map(|r| r.ok())
.collect::<Vec<VolatileSlice>>();
loop {
let res = if let Some(offset) = file_offset {
unsafe {
libc::pwritev64(
self.0.duped_fd.as_raw_fd(),
iovecs.as_ptr() as *mut _,
iovecs.len() as i32,
offset as libc::off64_t,
)
}
} else {
unsafe {
libc::writev(
self.0.duped_fd.as_raw_fd(),
iovecs.as_ptr() as *mut _,
iovecs.len() as i32,
)
}
};
if res >= 0 {
return Ok(res as usize);
}
match base::Error::last() {
e if e.errno() == libc::EWOULDBLOCK => {
let op = self.0.wait_writable().map_err(Error::AddingWaker)?;
op.await.map_err(Error::Executor)?;
}
e => return Err(Error::Write(e).into()),
}
}
}
pub async fn fallocate(
&self,
file_offset: u64,
len: u64,
mode: AllocateMode,
) -> AsyncResult<()> {
let mode_u32: u32 = mode.into();
let ret = unsafe {
libc::fallocate64(
self.0.duped_fd.as_raw_fd(),
mode_u32 as libc::c_int,
file_offset as libc::off64_t,
len as libc::off64_t,
)
};
if ret == 0 {
Ok(())
} else {
Err(AsyncError::Poll(Error::Fallocate(base::Error::last())))
}
}
pub async fn fsync(&self) -> AsyncResult<()> {
let ret = unsafe { libc::fsync(self.0.duped_fd.as_raw_fd()) };
if ret == 0 {
Ok(())
} else {
Err(AsyncError::Poll(Error::Fsync(base::Error::last())))
}
}
pub async fn fdatasync(&self) -> AsyncResult<()> {
let ret = unsafe { libc::fdatasync(self.0.duped_fd.as_raw_fd()) };
if ret == 0 {
Ok(())
} else {
Err(AsyncError::Poll(Error::Fdatasync(base::Error::last())))
}
}
pub fn into_source(self) -> F {
self.0.source
}
pub fn as_source_mut(&mut self) -> &mut F {
&mut self.0.source
}
pub fn as_source(&self) -> &F {
&self.0.source
}
}
#[cfg(test)]
mod tests {
use std::fs::File;
use std::fs::OpenOptions;
use std::path::PathBuf;
use super::*;
#[test]
fn fallocate() {
async fn go(ex: &Arc<RawExecutor<EpollReactor>>) {
let dir = tempfile::TempDir::new().unwrap();
let mut file_path = PathBuf::from(dir.path());
file_path.push("test");
let f = OpenOptions::new()
.create(true)
.write(true)
.open(&file_path)
.unwrap();
let source = PollSource::new(f, ex).unwrap();
source
.fallocate(0, 4096, AllocateMode::Allocate)
.await
.unwrap();
let meta_data = std::fs::metadata(&file_path).unwrap();
assert_eq!(meta_data.len(), 4096);
}
let ex = RawExecutor::<EpollReactor>::new().unwrap();
ex.run_until(go(&ex)).unwrap();
}
#[test]
fn memory_leak() {
async fn owns_poll_source(source: PollSource<File>) {
let _ = source.wait_readable().await;
}
let (rx, _tx) = base::pipe(true).unwrap();
let ex = RawExecutor::<EpollReactor>::new().unwrap();
let source = PollSource::new(rx, &ex).unwrap();
ex.spawn_local(owns_poll_source(source)).detach();
}
}