1
0
Fork 0
mirror of https://github.com/denoland/deno.git synced 2024-12-27 01:29:14 -05:00
denoland-deno/ext/io/lib.rs

903 lines
24 KiB
Rust
Raw Normal View History

// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
2020-09-21 08:26:41 -04:00
use deno_core::error::AnyError;
use deno_core::op2;
use deno_core::unsync::spawn_blocking;
use deno_core::unsync::TaskQueue;
use deno_core::AsyncMutFuture;
use deno_core::AsyncRefCell;
use deno_core::AsyncResult;
feat(core): improve resource read & write traits (#16115) This commit introduces two new buffer wrapper types to `deno_core`. The main benefit of these new wrappers is that they can wrap a number of different underlying buffer types. This allows for a more flexible read and write API on resources that will require less copying of data between different buffer representations. - `BufView` is a read-only view onto a buffer. It can be backed by `ZeroCopyBuf`, `Vec<u8>`, and `bytes::Bytes`. - `BufViewMut` is a read-write view onto a buffer. It can be cheaply converted into a `BufView`. It can be backed by `ZeroCopyBuf` or `Vec<u8>`. Both new buffer views have a cursor. This means that the start point of the view can be constrained to write / read from just a slice of the view. Only the start point of the slice can be adjusted. The end point is fixed. To adjust the end point, the underlying buffer needs to be truncated. Readable resources have been changed to better cater to resources that do not support BYOB reads. The basic `read` method now returns a `BufView` instead of taking a `ZeroCopyBuf` to fill. This allows the operation to return buffers that the resource has already allocated, instead of forcing the caller to allocate the buffer. BYOB reads are still very useful for resources that support them, so a new `read_byob` method has been added that takes a `BufViewMut` to fill. `op_read` attempts to use `read_byob` if the resource supports it, which falls back to `read` and performs an additional copy if it does not. For Rust->JS reads this change should have no impact, but for Rust->Rust reads, this allows the caller to avoid an additional copy in many scenarios. This combined with the support for `BufView` to be backed by `bytes::Bytes` allows us to avoid one data copy when piping from a `fetch` response into an `ext/http` response. Writable resources have been changed to take a `BufView` instead of a `ZeroCopyBuf` as an argument. This allows for less copying of data in certain scenarios, as described above. Additionally a new `Resource::write_all` method has been added that takes a `BufView` and continually attempts to write the resource until the entire buffer has been written. Certain resources like files can override this method to provide a more efficient `write_all` implementation.
2022-10-09 10:49:25 -04:00
use deno_core::BufMutView;
use deno_core::BufView;
use deno_core::CancelHandle;
use deno_core::CancelTryFuture;
use deno_core::OpState;
use deno_core::RcRef;
use deno_core::Resource;
use deno_core::ResourceHandle;
use deno_core::ResourceHandleFd;
use fs::FileResource;
use fs::FsError;
use fs::FsResult;
use fs::FsStat;
use fs3::FileExt;
use once_cell::sync::Lazy;
use std::borrow::Cow;
use std::cell::RefCell;
2021-10-25 11:16:16 -04:00
use std::fs::File as StdFile;
use std::future::Future;
use std::io;
use std::io::ErrorKind;
use std::io::Read;
use std::io::Seek;
use std::io::Write;
use std::rc::Rc;
use tokio::io::AsyncRead;
use tokio::io::AsyncReadExt;
use tokio::io::AsyncWrite;
use tokio::io::AsyncWriteExt;
use tokio::process;
#[cfg(unix)]
use std::os::unix::io::FromRawFd;
#[cfg(windows)]
use std::os::windows::io::FromRawHandle;
#[cfg(windows)]
use winapi::um::processenv::GetStdHandle;
#[cfg(windows)]
use winapi::um::winbase;
#[cfg(windows)]
use parking_lot::Condvar;
#[cfg(windows)]
use parking_lot::Mutex;
#[cfg(windows)]
use std::sync::Arc;
pub mod fs;
mod pipe;
#[cfg(windows)]
mod winpipe;
pub use pipe::pipe;
pub use pipe::AsyncPipeRead;
pub use pipe::AsyncPipeWrite;
pub use pipe::PipeRead;
pub use pipe::PipeWrite;
// Store the stdio fd/handles in global statics in order to keep them
// alive for the duration of the application since the last handle/fd
// being dropped will close the corresponding pipe.
2021-10-25 11:16:16 -04:00
#[cfg(unix)]
pub static STDIN_HANDLE: Lazy<StdFile> = Lazy::new(|| {
// SAFETY: corresponds to OS stdin
unsafe { StdFile::from_raw_fd(0) }
});
#[cfg(unix)]
pub static STDOUT_HANDLE: Lazy<StdFile> = Lazy::new(|| {
// SAFETY: corresponds to OS stdout
unsafe { StdFile::from_raw_fd(1) }
});
#[cfg(unix)]
pub static STDERR_HANDLE: Lazy<StdFile> = Lazy::new(|| {
// SAFETY: corresponds to OS stderr
unsafe { StdFile::from_raw_fd(2) }
});
2021-10-25 11:16:16 -04:00
#[cfg(windows)]
pub static STDIN_HANDLE: Lazy<StdFile> = Lazy::new(|| {
// SAFETY: corresponds to OS stdin
unsafe { StdFile::from_raw_handle(GetStdHandle(winbase::STD_INPUT_HANDLE)) }
});
#[cfg(windows)]
pub static STDOUT_HANDLE: Lazy<StdFile> = Lazy::new(|| {
// SAFETY: corresponds to OS stdout
unsafe { StdFile::from_raw_handle(GetStdHandle(winbase::STD_OUTPUT_HANDLE)) }
});
#[cfg(windows)]
pub static STDERR_HANDLE: Lazy<StdFile> = Lazy::new(|| {
// SAFETY: corresponds to OS stderr
unsafe { StdFile::from_raw_handle(GetStdHandle(winbase::STD_ERROR_HANDLE)) }
});
deno_core::extension!(deno_io,
deps = [ deno_web ],
esm = [ "12_io.js" ],
options = {
stdio: Option<Stdio>,
},
middleware = |op| match op.name {
"op_print" => op_print(),
_ => op,
},
state = |state, options| {
if let Some(stdio) = options.stdio {
#[cfg(windows)]
let stdin_state = {
let st = Arc::new(Mutex::new(WinTtyState::default()));
state.put(st.clone());
st
};
#[cfg(unix)]
let stdin_state = ();
let t = &mut state.resource_table;
let rid = t.add(fs::FileResource::new(
Rc::new(match stdio.stdin.pipe {
StdioPipeInner::Inherit => StdFileResourceInner::new(
StdFileResourceKind::Stdin(stdin_state),
STDIN_HANDLE.try_clone().unwrap(),
),
StdioPipeInner::File(pipe) => StdFileResourceInner::file(pipe),
}),
"stdin".to_string(),
));
assert_eq!(rid, 0, "stdin must have ResourceId 0");
let rid = t.add(FileResource::new(
Rc::new(match stdio.stdout.pipe {
StdioPipeInner::Inherit => StdFileResourceInner::new(
StdFileResourceKind::Stdout,
STDOUT_HANDLE.try_clone().unwrap(),
),
StdioPipeInner::File(pipe) => StdFileResourceInner::file(pipe),
}),
"stdout".to_string(),
));
assert_eq!(rid, 1, "stdout must have ResourceId 1");
let rid = t.add(FileResource::new(
Rc::new(match stdio.stderr.pipe {
StdioPipeInner::Inherit => StdFileResourceInner::new(
StdFileResourceKind::Stderr,
STDERR_HANDLE.try_clone().unwrap(),
),
StdioPipeInner::File(pipe) => StdFileResourceInner::file(pipe),
}),
"stderr".to_string(),
));
assert_eq!(rid, 2, "stderr must have ResourceId 2");
}
},
);
#[derive(Default)]
pub struct StdioPipe {
pipe: StdioPipeInner,
}
impl StdioPipe {
pub const fn inherit() -> Self {
StdioPipe {
pipe: StdioPipeInner::Inherit,
}
}
pub fn file(f: impl Into<StdFile>) -> Self {
StdioPipe {
pipe: StdioPipeInner::File(f.into()),
}
}
}
#[derive(Default)]
enum StdioPipeInner {
#[default]
Inherit,
File(StdFile),
}
impl Clone for StdioPipe {
fn clone(&self) -> Self {
match &self.pipe {
StdioPipeInner::Inherit => Self {
pipe: StdioPipeInner::Inherit,
},
StdioPipeInner::File(pipe) => Self {
pipe: StdioPipeInner::File(pipe.try_clone().unwrap()),
},
}
}
}
/// Specify how stdin, stdout, and stderr are piped.
/// By default, inherits from the process.
#[derive(Clone, Default)]
pub struct Stdio {
pub stdin: StdioPipe,
pub stdout: StdioPipe,
pub stderr: StdioPipe,
}
#[derive(Debug)]
pub struct WriteOnlyResource<S> {
stream: AsyncRefCell<S>,
}
impl<S: 'static> From<S> for WriteOnlyResource<S> {
fn from(stream: S) -> Self {
Self {
stream: stream.into(),
}
}
}
impl<S> WriteOnlyResource<S>
where
S: AsyncWrite + Unpin + 'static,
{
pub fn borrow_mut(self: &Rc<Self>) -> AsyncMutFuture<S> {
RcRef::map(self, |r| &r.stream).borrow_mut()
}
feat(core): improve resource read & write traits (#16115) This commit introduces two new buffer wrapper types to `deno_core`. The main benefit of these new wrappers is that they can wrap a number of different underlying buffer types. This allows for a more flexible read and write API on resources that will require less copying of data between different buffer representations. - `BufView` is a read-only view onto a buffer. It can be backed by `ZeroCopyBuf`, `Vec<u8>`, and `bytes::Bytes`. - `BufViewMut` is a read-write view onto a buffer. It can be cheaply converted into a `BufView`. It can be backed by `ZeroCopyBuf` or `Vec<u8>`. Both new buffer views have a cursor. This means that the start point of the view can be constrained to write / read from just a slice of the view. Only the start point of the slice can be adjusted. The end point is fixed. To adjust the end point, the underlying buffer needs to be truncated. Readable resources have been changed to better cater to resources that do not support BYOB reads. The basic `read` method now returns a `BufView` instead of taking a `ZeroCopyBuf` to fill. This allows the operation to return buffers that the resource has already allocated, instead of forcing the caller to allocate the buffer. BYOB reads are still very useful for resources that support them, so a new `read_byob` method has been added that takes a `BufViewMut` to fill. `op_read` attempts to use `read_byob` if the resource supports it, which falls back to `read` and performs an additional copy if it does not. For Rust->JS reads this change should have no impact, but for Rust->Rust reads, this allows the caller to avoid an additional copy in many scenarios. This combined with the support for `BufView` to be backed by `bytes::Bytes` allows us to avoid one data copy when piping from a `fetch` response into an `ext/http` response. Writable resources have been changed to take a `BufView` instead of a `ZeroCopyBuf` as an argument. This allows for less copying of data in certain scenarios, as described above. Additionally a new `Resource::write_all` method has been added that takes a `BufView` and continually attempts to write the resource until the entire buffer has been written. Certain resources like files can override this method to provide a more efficient `write_all` implementation.
2022-10-09 10:49:25 -04:00
async fn write(self: Rc<Self>, data: &[u8]) -> Result<usize, AnyError> {
let mut stream = self.borrow_mut().await;
feat(core): improve resource read & write traits (#16115) This commit introduces two new buffer wrapper types to `deno_core`. The main benefit of these new wrappers is that they can wrap a number of different underlying buffer types. This allows for a more flexible read and write API on resources that will require less copying of data between different buffer representations. - `BufView` is a read-only view onto a buffer. It can be backed by `ZeroCopyBuf`, `Vec<u8>`, and `bytes::Bytes`. - `BufViewMut` is a read-write view onto a buffer. It can be cheaply converted into a `BufView`. It can be backed by `ZeroCopyBuf` or `Vec<u8>`. Both new buffer views have a cursor. This means that the start point of the view can be constrained to write / read from just a slice of the view. Only the start point of the slice can be adjusted. The end point is fixed. To adjust the end point, the underlying buffer needs to be truncated. Readable resources have been changed to better cater to resources that do not support BYOB reads. The basic `read` method now returns a `BufView` instead of taking a `ZeroCopyBuf` to fill. This allows the operation to return buffers that the resource has already allocated, instead of forcing the caller to allocate the buffer. BYOB reads are still very useful for resources that support them, so a new `read_byob` method has been added that takes a `BufViewMut` to fill. `op_read` attempts to use `read_byob` if the resource supports it, which falls back to `read` and performs an additional copy if it does not. For Rust->JS reads this change should have no impact, but for Rust->Rust reads, this allows the caller to avoid an additional copy in many scenarios. This combined with the support for `BufView` to be backed by `bytes::Bytes` allows us to avoid one data copy when piping from a `fetch` response into an `ext/http` response. Writable resources have been changed to take a `BufView` instead of a `ZeroCopyBuf` as an argument. This allows for less copying of data in certain scenarios, as described above. Additionally a new `Resource::write_all` method has been added that takes a `BufView` and continually attempts to write the resource until the entire buffer has been written. Certain resources like files can override this method to provide a more efficient `write_all` implementation.
2022-10-09 10:49:25 -04:00
let nwritten = stream.write(data).await?;
Ok(nwritten)
}
async fn shutdown(self: Rc<Self>) -> Result<(), AnyError> {
let mut stream = self.borrow_mut().await;
stream.shutdown().await?;
Ok(())
}
pub fn into_inner(self) -> S {
self.stream.into_inner()
}
}
#[derive(Debug)]
pub struct ReadOnlyResource<S> {
stream: AsyncRefCell<S>,
cancel_handle: CancelHandle,
}
impl<S: 'static> From<S> for ReadOnlyResource<S> {
fn from(stream: S) -> Self {
Self {
stream: stream.into(),
cancel_handle: Default::default(),
}
}
}
impl<S> ReadOnlyResource<S>
where
S: AsyncRead + Unpin + 'static,
{
pub fn borrow_mut(self: &Rc<Self>) -> AsyncMutFuture<S> {
RcRef::map(self, |r| &r.stream).borrow_mut()
}
pub fn cancel_handle(self: &Rc<Self>) -> RcRef<CancelHandle> {
RcRef::map(self, |r| &r.cancel_handle)
}
pub fn cancel_read_ops(&self) {
self.cancel_handle.cancel()
}
feat(core): improve resource read & write traits (#16115) This commit introduces two new buffer wrapper types to `deno_core`. The main benefit of these new wrappers is that they can wrap a number of different underlying buffer types. This allows for a more flexible read and write API on resources that will require less copying of data between different buffer representations. - `BufView` is a read-only view onto a buffer. It can be backed by `ZeroCopyBuf`, `Vec<u8>`, and `bytes::Bytes`. - `BufViewMut` is a read-write view onto a buffer. It can be cheaply converted into a `BufView`. It can be backed by `ZeroCopyBuf` or `Vec<u8>`. Both new buffer views have a cursor. This means that the start point of the view can be constrained to write / read from just a slice of the view. Only the start point of the slice can be adjusted. The end point is fixed. To adjust the end point, the underlying buffer needs to be truncated. Readable resources have been changed to better cater to resources that do not support BYOB reads. The basic `read` method now returns a `BufView` instead of taking a `ZeroCopyBuf` to fill. This allows the operation to return buffers that the resource has already allocated, instead of forcing the caller to allocate the buffer. BYOB reads are still very useful for resources that support them, so a new `read_byob` method has been added that takes a `BufViewMut` to fill. `op_read` attempts to use `read_byob` if the resource supports it, which falls back to `read` and performs an additional copy if it does not. For Rust->JS reads this change should have no impact, but for Rust->Rust reads, this allows the caller to avoid an additional copy in many scenarios. This combined with the support for `BufView` to be backed by `bytes::Bytes` allows us to avoid one data copy when piping from a `fetch` response into an `ext/http` response. Writable resources have been changed to take a `BufView` instead of a `ZeroCopyBuf` as an argument. This allows for less copying of data in certain scenarios, as described above. Additionally a new `Resource::write_all` method has been added that takes a `BufView` and continually attempts to write the resource until the entire buffer has been written. Certain resources like files can override this method to provide a more efficient `write_all` implementation.
2022-10-09 10:49:25 -04:00
async fn read(self: Rc<Self>, data: &mut [u8]) -> Result<usize, AnyError> {
let mut rd = self.borrow_mut().await;
feat(core): improve resource read & write traits (#16115) This commit introduces two new buffer wrapper types to `deno_core`. The main benefit of these new wrappers is that they can wrap a number of different underlying buffer types. This allows for a more flexible read and write API on resources that will require less copying of data between different buffer representations. - `BufView` is a read-only view onto a buffer. It can be backed by `ZeroCopyBuf`, `Vec<u8>`, and `bytes::Bytes`. - `BufViewMut` is a read-write view onto a buffer. It can be cheaply converted into a `BufView`. It can be backed by `ZeroCopyBuf` or `Vec<u8>`. Both new buffer views have a cursor. This means that the start point of the view can be constrained to write / read from just a slice of the view. Only the start point of the slice can be adjusted. The end point is fixed. To adjust the end point, the underlying buffer needs to be truncated. Readable resources have been changed to better cater to resources that do not support BYOB reads. The basic `read` method now returns a `BufView` instead of taking a `ZeroCopyBuf` to fill. This allows the operation to return buffers that the resource has already allocated, instead of forcing the caller to allocate the buffer. BYOB reads are still very useful for resources that support them, so a new `read_byob` method has been added that takes a `BufViewMut` to fill. `op_read` attempts to use `read_byob` if the resource supports it, which falls back to `read` and performs an additional copy if it does not. For Rust->JS reads this change should have no impact, but for Rust->Rust reads, this allows the caller to avoid an additional copy in many scenarios. This combined with the support for `BufView` to be backed by `bytes::Bytes` allows us to avoid one data copy when piping from a `fetch` response into an `ext/http` response. Writable resources have been changed to take a `BufView` instead of a `ZeroCopyBuf` as an argument. This allows for less copying of data in certain scenarios, as described above. Additionally a new `Resource::write_all` method has been added that takes a `BufView` and continually attempts to write the resource until the entire buffer has been written. Certain resources like files can override this method to provide a more efficient `write_all` implementation.
2022-10-09 10:49:25 -04:00
let nread = rd.read(data).try_or_cancel(self.cancel_handle()).await?;
Ok(nread)
}
pub fn into_inner(self) -> S {
self.stream.into_inner()
}
}
pub type ChildStdinResource = WriteOnlyResource<process::ChildStdin>;
impl Resource for ChildStdinResource {
fn name(&self) -> Cow<str> {
"childStdin".into()
}
feat(core): improve resource read & write traits (#16115) This commit introduces two new buffer wrapper types to `deno_core`. The main benefit of these new wrappers is that they can wrap a number of different underlying buffer types. This allows for a more flexible read and write API on resources that will require less copying of data between different buffer representations. - `BufView` is a read-only view onto a buffer. It can be backed by `ZeroCopyBuf`, `Vec<u8>`, and `bytes::Bytes`. - `BufViewMut` is a read-write view onto a buffer. It can be cheaply converted into a `BufView`. It can be backed by `ZeroCopyBuf` or `Vec<u8>`. Both new buffer views have a cursor. This means that the start point of the view can be constrained to write / read from just a slice of the view. Only the start point of the slice can be adjusted. The end point is fixed. To adjust the end point, the underlying buffer needs to be truncated. Readable resources have been changed to better cater to resources that do not support BYOB reads. The basic `read` method now returns a `BufView` instead of taking a `ZeroCopyBuf` to fill. This allows the operation to return buffers that the resource has already allocated, instead of forcing the caller to allocate the buffer. BYOB reads are still very useful for resources that support them, so a new `read_byob` method has been added that takes a `BufViewMut` to fill. `op_read` attempts to use `read_byob` if the resource supports it, which falls back to `read` and performs an additional copy if it does not. For Rust->JS reads this change should have no impact, but for Rust->Rust reads, this allows the caller to avoid an additional copy in many scenarios. This combined with the support for `BufView` to be backed by `bytes::Bytes` allows us to avoid one data copy when piping from a `fetch` response into an `ext/http` response. Writable resources have been changed to take a `BufView` instead of a `ZeroCopyBuf` as an argument. This allows for less copying of data in certain scenarios, as described above. Additionally a new `Resource::write_all` method has been added that takes a `BufView` and continually attempts to write the resource until the entire buffer has been written. Certain resources like files can override this method to provide a more efficient `write_all` implementation.
2022-10-09 10:49:25 -04:00
deno_core::impl_writable!();
fn shutdown(self: Rc<Self>) -> AsyncResult<()> {
Box::pin(self.shutdown())
}
}
pub type ChildStdoutResource = ReadOnlyResource<process::ChildStdout>;
impl Resource for ChildStdoutResource {
feat(core): improve resource read & write traits (#16115) This commit introduces two new buffer wrapper types to `deno_core`. The main benefit of these new wrappers is that they can wrap a number of different underlying buffer types. This allows for a more flexible read and write API on resources that will require less copying of data between different buffer representations. - `BufView` is a read-only view onto a buffer. It can be backed by `ZeroCopyBuf`, `Vec<u8>`, and `bytes::Bytes`. - `BufViewMut` is a read-write view onto a buffer. It can be cheaply converted into a `BufView`. It can be backed by `ZeroCopyBuf` or `Vec<u8>`. Both new buffer views have a cursor. This means that the start point of the view can be constrained to write / read from just a slice of the view. Only the start point of the slice can be adjusted. The end point is fixed. To adjust the end point, the underlying buffer needs to be truncated. Readable resources have been changed to better cater to resources that do not support BYOB reads. The basic `read` method now returns a `BufView` instead of taking a `ZeroCopyBuf` to fill. This allows the operation to return buffers that the resource has already allocated, instead of forcing the caller to allocate the buffer. BYOB reads are still very useful for resources that support them, so a new `read_byob` method has been added that takes a `BufViewMut` to fill. `op_read` attempts to use `read_byob` if the resource supports it, which falls back to `read` and performs an additional copy if it does not. For Rust->JS reads this change should have no impact, but for Rust->Rust reads, this allows the caller to avoid an additional copy in many scenarios. This combined with the support for `BufView` to be backed by `bytes::Bytes` allows us to avoid one data copy when piping from a `fetch` response into an `ext/http` response. Writable resources have been changed to take a `BufView` instead of a `ZeroCopyBuf` as an argument. This allows for less copying of data in certain scenarios, as described above. Additionally a new `Resource::write_all` method has been added that takes a `BufView` and continually attempts to write the resource until the entire buffer has been written. Certain resources like files can override this method to provide a more efficient `write_all` implementation.
2022-10-09 10:49:25 -04:00
deno_core::impl_readable_byob!();
fn name(&self) -> Cow<str> {
"childStdout".into()
}
fn close(self: Rc<Self>) {
self.cancel_read_ops();
}
}
pub type ChildStderrResource = ReadOnlyResource<process::ChildStderr>;
impl Resource for ChildStderrResource {
feat(core): improve resource read & write traits (#16115) This commit introduces two new buffer wrapper types to `deno_core`. The main benefit of these new wrappers is that they can wrap a number of different underlying buffer types. This allows for a more flexible read and write API on resources that will require less copying of data between different buffer representations. - `BufView` is a read-only view onto a buffer. It can be backed by `ZeroCopyBuf`, `Vec<u8>`, and `bytes::Bytes`. - `BufViewMut` is a read-write view onto a buffer. It can be cheaply converted into a `BufView`. It can be backed by `ZeroCopyBuf` or `Vec<u8>`. Both new buffer views have a cursor. This means that the start point of the view can be constrained to write / read from just a slice of the view. Only the start point of the slice can be adjusted. The end point is fixed. To adjust the end point, the underlying buffer needs to be truncated. Readable resources have been changed to better cater to resources that do not support BYOB reads. The basic `read` method now returns a `BufView` instead of taking a `ZeroCopyBuf` to fill. This allows the operation to return buffers that the resource has already allocated, instead of forcing the caller to allocate the buffer. BYOB reads are still very useful for resources that support them, so a new `read_byob` method has been added that takes a `BufViewMut` to fill. `op_read` attempts to use `read_byob` if the resource supports it, which falls back to `read` and performs an additional copy if it does not. For Rust->JS reads this change should have no impact, but for Rust->Rust reads, this allows the caller to avoid an additional copy in many scenarios. This combined with the support for `BufView` to be backed by `bytes::Bytes` allows us to avoid one data copy when piping from a `fetch` response into an `ext/http` response. Writable resources have been changed to take a `BufView` instead of a `ZeroCopyBuf` as an argument. This allows for less copying of data in certain scenarios, as described above. Additionally a new `Resource::write_all` method has been added that takes a `BufView` and continually attempts to write the resource until the entire buffer has been written. Certain resources like files can override this method to provide a more efficient `write_all` implementation.
2022-10-09 10:49:25 -04:00
deno_core::impl_readable_byob!();
fn name(&self) -> Cow<str> {
"childStderr".into()
}
fn close(self: Rc<Self>) {
self.cancel_read_ops();
}
}
#[cfg(windows)]
#[derive(Default)]
pub struct WinTtyState {
pub cancelled: bool,
pub reading: bool,
pub screen_buffer_info:
Option<winapi::um::wincon::CONSOLE_SCREEN_BUFFER_INFO>,
pub cvar: Arc<Condvar>,
}
#[derive(Clone)]
enum StdFileResourceKind {
File,
// For stdout and stderr, we sometimes instead use std::io::stdout() directly,
// because we get some Windows specific functionality for free by using Rust
// std's wrappers. So we take a bit of a complexity hit in order to not
// have to duplicate the functionality in Rust's std/src/sys/windows/stdio.rs
#[cfg(windows)]
Stdin(Arc<Mutex<WinTtyState>>),
#[cfg(not(windows))]
Stdin(()),
Stdout,
Stderr,
}
pub struct StdFileResourceInner {
kind: StdFileResourceKind,
// We can't use an AsyncRefCell here because we need to allow
// access to the resource synchronously at any time and
// asynchronously one at a time in order
cell: RefCell<Option<StdFile>>,
// Used to keep async actions in order and only allow one
// to occur at a time
cell_async_task_queue: Rc<TaskQueue>,
handle: ResourceHandleFd,
}
impl StdFileResourceInner {
pub fn file(fs_file: StdFile) -> Self {
StdFileResourceInner::new(StdFileResourceKind::File, fs_file)
}
fn new(kind: StdFileResourceKind, fs_file: StdFile) -> Self {
// We know this will be an fd
let handle = ResourceHandle::from_fd_like(&fs_file).as_fd_like().unwrap();
StdFileResourceInner {
kind,
handle,
cell: RefCell::new(Some(fs_file)),
cell_async_task_queue: Default::default(),
}
}
fn with_sync<F, R>(&self, action: F) -> FsResult<R>
where
F: FnOnce(&mut StdFile) -> FsResult<R>,
{
match self.cell.try_borrow_mut() {
Ok(mut cell) if cell.is_some() => action(cell.as_mut().unwrap()),
_ => Err(fs::FsError::FileBusy),
}
}
fn with_inner_blocking_task<F, R: 'static + Send>(
&self,
action: F,
) -> impl Future<Output = R> + '_
where
F: FnOnce(&mut StdFile) -> R + Send + 'static,
{
// we want to restrict this to one async action at a time
let acquire_fut = self.cell_async_task_queue.acquire();
async move {
let permit = acquire_fut.await;
// we take the value out of the cell, use it on a blocking task,
// then put it back into the cell when we're done
let mut did_take = false;
let mut cell_value = {
let mut cell = self.cell.borrow_mut();
match cell.as_mut().unwrap().try_clone().ok() {
Some(value) => value,
None => {
did_take = true;
cell.take().unwrap()
}
}
};
let (cell_value, result) = spawn_blocking(move || {
let result = action(&mut cell_value);
(cell_value, result)
})
.await
.unwrap();
if did_take {
// put it back
self.cell.borrow_mut().replace(cell_value);
}
drop(permit); // explicit for clarity
result
}
}
fn with_blocking_task<F, R: 'static + Send>(
&self,
action: F,
) -> impl Future<Output = R>
where
F: FnOnce() -> R + Send + 'static,
{
// we want to restrict this to one async action at a time
let acquire_fut = self.cell_async_task_queue.acquire();
async move {
let _permit = acquire_fut.await;
spawn_blocking(action).await.unwrap()
}
}
#[cfg(windows)]
async fn handle_stdin_read(
&self,
state: Arc<Mutex<WinTtyState>>,
mut buf: BufMutView,
) -> FsResult<(usize, BufMutView)> {
loop {
let state = state.clone();
let fut = self.with_inner_blocking_task(move |file| {
/* Start reading, and set the reading flag to true */
state.lock().reading = true;
let nread = match file.read(&mut buf) {
Ok(nread) => nread,
Err(e) => return Err((e.into(), buf)),
};
let mut state = state.lock();
state.reading = false;
/* If we canceled the read by sending a VK_RETURN event, restore
the screen state to undo the visual effect of the VK_RETURN event */
if state.cancelled {
if let Some(screen_buffer_info) = state.screen_buffer_info {
// SAFETY: WinAPI calls to open conout$ and restore visual state.
unsafe {
let handle = winapi::um::fileapi::CreateFileW(
"conout$"
.encode_utf16()
.chain(Some(0))
.collect::<Vec<_>>()
.as_ptr(),
winapi::um::winnt::GENERIC_READ
| winapi::um::winnt::GENERIC_WRITE,
winapi::um::winnt::FILE_SHARE_READ
| winapi::um::winnt::FILE_SHARE_WRITE,
std::ptr::null_mut(),
winapi::um::fileapi::OPEN_EXISTING,
0,
std::ptr::null_mut(),
);
let mut pos = screen_buffer_info.dwCursorPosition;
/* If the cursor was at the bottom line of the screen buffer, the
VK_RETURN would have caused the buffer contents to scroll up by
one line. The right position to reset the cursor to is therefore one
line higher */
if pos.Y == screen_buffer_info.dwSize.Y - 1 {
pos.Y -= 1;
}
winapi::um::wincon::SetConsoleCursorPosition(handle, pos);
winapi::um::handleapi::CloseHandle(handle);
}
}
/* Reset the cancelled flag */
state.cancelled = false;
/* Unblock the main thread */
state.cvar.notify_one();
return Err((FsError::FileBusy, buf));
}
Ok((nread, buf))
});
match fut.await {
Err((FsError::FileBusy, b)) => {
buf = b;
continue;
}
other => return other.map_err(|(e, _)| e),
}
}
}
}
#[async_trait::async_trait(?Send)]
impl crate::fs::File for StdFileResourceInner {
fn write_sync(self: Rc<Self>, buf: &[u8]) -> FsResult<usize> {
// Rust will line buffer and we don't want that behavior
// (see https://github.com/denoland/deno/issues/948), so flush stdout and stderr.
// Although an alternative solution could be to bypass Rust's std by
// using the raw fds/handles, it will cause encoding issues on Windows
// that we get solved for free by using Rust's stdio wrappers (see
// std/src/sys/windows/stdio.rs in Rust's source code).
match self.kind {
StdFileResourceKind::File => self.with_sync(|file| Ok(file.write(buf)?)),
StdFileResourceKind::Stdin(_) => {
Err(Into::<std::io::Error>::into(ErrorKind::Unsupported).into())
}
StdFileResourceKind::Stdout => {
// bypass the file and use std::io::stdout()
let mut stdout = std::io::stdout().lock();
let nwritten = stdout.write(buf)?;
stdout.flush()?;
Ok(nwritten)
}
StdFileResourceKind::Stderr => {
// bypass the file and use std::io::stderr()
let mut stderr = std::io::stderr().lock();
let nwritten = stderr.write(buf)?;
stderr.flush()?;
Ok(nwritten)
}
}
}
fn read_sync(self: Rc<Self>, buf: &mut [u8]) -> FsResult<usize> {
match self.kind {
StdFileResourceKind::File | StdFileResourceKind::Stdin(_) => {
self.with_sync(|file| Ok(file.read(buf)?))
}
StdFileResourceKind::Stdout | StdFileResourceKind::Stderr => {
Err(FsError::NotSupported)
}
}
}
fn write_all_sync(self: Rc<Self>, buf: &[u8]) -> FsResult<()> {
match self.kind {
StdFileResourceKind::File => {
self.with_sync(|file| Ok(file.write_all(buf)?))
}
StdFileResourceKind::Stdin(_) => {
Err(Into::<std::io::Error>::into(ErrorKind::Unsupported).into())
}
StdFileResourceKind::Stdout => {
// bypass the file and use std::io::stdout()
let mut stdout = std::io::stdout().lock();
stdout.write_all(buf)?;
stdout.flush()?;
Ok(())
}
StdFileResourceKind::Stderr => {
// bypass the file and use std::io::stderr()
let mut stderr = std::io::stderr().lock();
stderr.write_all(buf)?;
stderr.flush()?;
Ok(())
}
}
}
async fn write_all(self: Rc<Self>, buf: BufView) -> FsResult<()> {
match self.kind {
StdFileResourceKind::File => {
self
.with_inner_blocking_task(move |file| Ok(file.write_all(&buf)?))
.await
}
StdFileResourceKind::Stdin(_) => {
Err(Into::<std::io::Error>::into(ErrorKind::Unsupported).into())
}
StdFileResourceKind::Stdout => {
self
.with_blocking_task(move || {
// bypass the file and use std::io::stdout()
let mut stdout = std::io::stdout().lock();
stdout.write_all(&buf)?;
stdout.flush()?;
Ok(())
})
.await
}
StdFileResourceKind::Stderr => {
self
.with_blocking_task(move || {
// bypass the file and use std::io::stderr()
let mut stderr = std::io::stderr().lock();
stderr.write_all(&buf)?;
stderr.flush()?;
Ok(())
})
.await
}
}
}
async fn write(
self: Rc<Self>,
view: BufView,
) -> FsResult<deno_core::WriteOutcome> {
match self.kind {
StdFileResourceKind::File => {
self
.with_inner_blocking_task(|file| {
let nwritten = file.write(&view)?;
Ok(deno_core::WriteOutcome::Partial { nwritten, view })
})
.await
}
StdFileResourceKind::Stdin(_) => {
Err(Into::<std::io::Error>::into(ErrorKind::Unsupported).into())
}
StdFileResourceKind::Stdout => {
self
.with_blocking_task(|| {
// bypass the file and use std::io::stdout()
let mut stdout = std::io::stdout().lock();
let nwritten = stdout.write(&view)?;
stdout.flush()?;
Ok(deno_core::WriteOutcome::Partial { nwritten, view })
})
.await
}
StdFileResourceKind::Stderr => {
self
.with_blocking_task(|| {
// bypass the file and use std::io::stderr()
let mut stderr = std::io::stderr().lock();
let nwritten = stderr.write(&view)?;
stderr.flush()?;
Ok(deno_core::WriteOutcome::Partial { nwritten, view })
})
.await
}
}
}
fn read_all_sync(self: Rc<Self>) -> FsResult<Vec<u8>> {
match self.kind {
StdFileResourceKind::File | StdFileResourceKind::Stdin(_) => {
let mut buf = Vec::new();
self.with_sync(|file| Ok(file.read_to_end(&mut buf)?))?;
Ok(buf)
}
StdFileResourceKind::Stdout | StdFileResourceKind::Stderr => {
Err(FsError::NotSupported)
}
}
}
async fn read_all_async(self: Rc<Self>) -> FsResult<Vec<u8>> {
match self.kind {
StdFileResourceKind::File | StdFileResourceKind::Stdin(_) => {
self
.with_inner_blocking_task(|file| {
let mut buf = Vec::new();
file.read_to_end(&mut buf)?;
Ok(buf)
})
.await
}
StdFileResourceKind::Stdout | StdFileResourceKind::Stderr => {
Err(FsError::NotSupported)
}
}
}
fn chmod_sync(self: Rc<Self>, _mode: u32) -> FsResult<()> {
#[cfg(unix)]
{
use std::os::unix::prelude::PermissionsExt;
self.with_sync(|file| {
Ok(file.set_permissions(std::fs::Permissions::from_mode(_mode))?)
})
}
#[cfg(not(unix))]
Err(FsError::NotSupported)
}
async fn chmod_async(self: Rc<Self>, _mode: u32) -> FsResult<()> {
#[cfg(unix)]
{
use std::os::unix::prelude::PermissionsExt;
self
.with_inner_blocking_task(move |file| {
Ok(file.set_permissions(std::fs::Permissions::from_mode(_mode))?)
})
.await
}
#[cfg(not(unix))]
Err(FsError::NotSupported)
}
fn seek_sync(self: Rc<Self>, pos: io::SeekFrom) -> FsResult<u64> {
self.with_sync(|file| Ok(file.seek(pos)?))
}
async fn seek_async(self: Rc<Self>, pos: io::SeekFrom) -> FsResult<u64> {
self
.with_inner_blocking_task(move |file| Ok(file.seek(pos)?))
.await
}
fn datasync_sync(self: Rc<Self>) -> FsResult<()> {
self.with_sync(|file| Ok(file.sync_data()?))
}
async fn datasync_async(self: Rc<Self>) -> FsResult<()> {
self
.with_inner_blocking_task(|file| Ok(file.sync_data()?))
.await
}
fn sync_sync(self: Rc<Self>) -> FsResult<()> {
self.with_sync(|file| Ok(file.sync_all()?))
}
async fn sync_async(self: Rc<Self>) -> FsResult<()> {
feat(core): improve resource read & write traits (#16115) This commit introduces two new buffer wrapper types to `deno_core`. The main benefit of these new wrappers is that they can wrap a number of different underlying buffer types. This allows for a more flexible read and write API on resources that will require less copying of data between different buffer representations. - `BufView` is a read-only view onto a buffer. It can be backed by `ZeroCopyBuf`, `Vec<u8>`, and `bytes::Bytes`. - `BufViewMut` is a read-write view onto a buffer. It can be cheaply converted into a `BufView`. It can be backed by `ZeroCopyBuf` or `Vec<u8>`. Both new buffer views have a cursor. This means that the start point of the view can be constrained to write / read from just a slice of the view. Only the start point of the slice can be adjusted. The end point is fixed. To adjust the end point, the underlying buffer needs to be truncated. Readable resources have been changed to better cater to resources that do not support BYOB reads. The basic `read` method now returns a `BufView` instead of taking a `ZeroCopyBuf` to fill. This allows the operation to return buffers that the resource has already allocated, instead of forcing the caller to allocate the buffer. BYOB reads are still very useful for resources that support them, so a new `read_byob` method has been added that takes a `BufViewMut` to fill. `op_read` attempts to use `read_byob` if the resource supports it, which falls back to `read` and performs an additional copy if it does not. For Rust->JS reads this change should have no impact, but for Rust->Rust reads, this allows the caller to avoid an additional copy in many scenarios. This combined with the support for `BufView` to be backed by `bytes::Bytes` allows us to avoid one data copy when piping from a `fetch` response into an `ext/http` response. Writable resources have been changed to take a `BufView` instead of a `ZeroCopyBuf` as an argument. This allows for less copying of data in certain scenarios, as described above. Additionally a new `Resource::write_all` method has been added that takes a `BufView` and continually attempts to write the resource until the entire buffer has been written. Certain resources like files can override this method to provide a more efficient `write_all` implementation.
2022-10-09 10:49:25 -04:00
self
.with_inner_blocking_task(|file| Ok(file.sync_all()?))
feat(core): improve resource read & write traits (#16115) This commit introduces two new buffer wrapper types to `deno_core`. The main benefit of these new wrappers is that they can wrap a number of different underlying buffer types. This allows for a more flexible read and write API on resources that will require less copying of data between different buffer representations. - `BufView` is a read-only view onto a buffer. It can be backed by `ZeroCopyBuf`, `Vec<u8>`, and `bytes::Bytes`. - `BufViewMut` is a read-write view onto a buffer. It can be cheaply converted into a `BufView`. It can be backed by `ZeroCopyBuf` or `Vec<u8>`. Both new buffer views have a cursor. This means that the start point of the view can be constrained to write / read from just a slice of the view. Only the start point of the slice can be adjusted. The end point is fixed. To adjust the end point, the underlying buffer needs to be truncated. Readable resources have been changed to better cater to resources that do not support BYOB reads. The basic `read` method now returns a `BufView` instead of taking a `ZeroCopyBuf` to fill. This allows the operation to return buffers that the resource has already allocated, instead of forcing the caller to allocate the buffer. BYOB reads are still very useful for resources that support them, so a new `read_byob` method has been added that takes a `BufViewMut` to fill. `op_read` attempts to use `read_byob` if the resource supports it, which falls back to `read` and performs an additional copy if it does not. For Rust->JS reads this change should have no impact, but for Rust->Rust reads, this allows the caller to avoid an additional copy in many scenarios. This combined with the support for `BufView` to be backed by `bytes::Bytes` allows us to avoid one data copy when piping from a `fetch` response into an `ext/http` response. Writable resources have been changed to take a `BufView` instead of a `ZeroCopyBuf` as an argument. This allows for less copying of data in certain scenarios, as described above. Additionally a new `Resource::write_all` method has been added that takes a `BufView` and continually attempts to write the resource until the entire buffer has been written. Certain resources like files can override this method to provide a more efficient `write_all` implementation.
2022-10-09 10:49:25 -04:00
.await
}
fn stat_sync(self: Rc<Self>) -> FsResult<FsStat> {
self.with_sync(|file| Ok(file.metadata().map(FsStat::from_std)?))
}
async fn stat_async(self: Rc<Self>) -> FsResult<FsStat> {
self
.with_inner_blocking_task(|file| {
Ok(file.metadata().map(FsStat::from_std)?)
})
.await
}
fn lock_sync(self: Rc<Self>, exclusive: bool) -> FsResult<()> {
self.with_sync(|file| {
if exclusive {
file.lock_exclusive()?;
} else {
file.lock_shared()?;
}
Ok(())
})
}
async fn lock_async(self: Rc<Self>, exclusive: bool) -> FsResult<()> {
self
.with_inner_blocking_task(move |file| {
if exclusive {
file.lock_exclusive()?;
} else {
file.lock_shared()?;
}
Ok(())
})
.await
}
fn unlock_sync(self: Rc<Self>) -> FsResult<()> {
self.with_sync(|file| Ok(file.unlock()?))
}
async fn unlock_async(self: Rc<Self>) -> FsResult<()> {
self
.with_inner_blocking_task(|file| Ok(file.unlock()?))
.await
}
fn truncate_sync(self: Rc<Self>, len: u64) -> FsResult<()> {
self.with_sync(|file| Ok(file.set_len(len)?))
}
async fn truncate_async(self: Rc<Self>, len: u64) -> FsResult<()> {
self
.with_inner_blocking_task(move |file| Ok(file.set_len(len)?))
.await
}
fn utime_sync(
self: Rc<Self>,
atime_secs: i64,
atime_nanos: u32,
mtime_secs: i64,
mtime_nanos: u32,
) -> FsResult<()> {
let atime = filetime::FileTime::from_unix_time(atime_secs, atime_nanos);
let mtime = filetime::FileTime::from_unix_time(mtime_secs, mtime_nanos);
self.with_sync(|file| {
filetime::set_file_handle_times(file, Some(atime), Some(mtime))?;
Ok(())
feat(core): improve resource read & write traits (#16115) This commit introduces two new buffer wrapper types to `deno_core`. The main benefit of these new wrappers is that they can wrap a number of different underlying buffer types. This allows for a more flexible read and write API on resources that will require less copying of data between different buffer representations. - `BufView` is a read-only view onto a buffer. It can be backed by `ZeroCopyBuf`, `Vec<u8>`, and `bytes::Bytes`. - `BufViewMut` is a read-write view onto a buffer. It can be cheaply converted into a `BufView`. It can be backed by `ZeroCopyBuf` or `Vec<u8>`. Both new buffer views have a cursor. This means that the start point of the view can be constrained to write / read from just a slice of the view. Only the start point of the slice can be adjusted. The end point is fixed. To adjust the end point, the underlying buffer needs to be truncated. Readable resources have been changed to better cater to resources that do not support BYOB reads. The basic `read` method now returns a `BufView` instead of taking a `ZeroCopyBuf` to fill. This allows the operation to return buffers that the resource has already allocated, instead of forcing the caller to allocate the buffer. BYOB reads are still very useful for resources that support them, so a new `read_byob` method has been added that takes a `BufViewMut` to fill. `op_read` attempts to use `read_byob` if the resource supports it, which falls back to `read` and performs an additional copy if it does not. For Rust->JS reads this change should have no impact, but for Rust->Rust reads, this allows the caller to avoid an additional copy in many scenarios. This combined with the support for `BufView` to be backed by `bytes::Bytes` allows us to avoid one data copy when piping from a `fetch` response into an `ext/http` response. Writable resources have been changed to take a `BufView` instead of a `ZeroCopyBuf` as an argument. This allows for less copying of data in certain scenarios, as described above. Additionally a new `Resource::write_all` method has been added that takes a `BufView` and continually attempts to write the resource until the entire buffer has been written. Certain resources like files can override this method to provide a more efficient `write_all` implementation.
2022-10-09 10:49:25 -04:00
})
}
async fn utime_async(
feat(core): improve resource read & write traits (#16115) This commit introduces two new buffer wrapper types to `deno_core`. The main benefit of these new wrappers is that they can wrap a number of different underlying buffer types. This allows for a more flexible read and write API on resources that will require less copying of data between different buffer representations. - `BufView` is a read-only view onto a buffer. It can be backed by `ZeroCopyBuf`, `Vec<u8>`, and `bytes::Bytes`. - `BufViewMut` is a read-write view onto a buffer. It can be cheaply converted into a `BufView`. It can be backed by `ZeroCopyBuf` or `Vec<u8>`. Both new buffer views have a cursor. This means that the start point of the view can be constrained to write / read from just a slice of the view. Only the start point of the slice can be adjusted. The end point is fixed. To adjust the end point, the underlying buffer needs to be truncated. Readable resources have been changed to better cater to resources that do not support BYOB reads. The basic `read` method now returns a `BufView` instead of taking a `ZeroCopyBuf` to fill. This allows the operation to return buffers that the resource has already allocated, instead of forcing the caller to allocate the buffer. BYOB reads are still very useful for resources that support them, so a new `read_byob` method has been added that takes a `BufViewMut` to fill. `op_read` attempts to use `read_byob` if the resource supports it, which falls back to `read` and performs an additional copy if it does not. For Rust->JS reads this change should have no impact, but for Rust->Rust reads, this allows the caller to avoid an additional copy in many scenarios. This combined with the support for `BufView` to be backed by `bytes::Bytes` allows us to avoid one data copy when piping from a `fetch` response into an `ext/http` response. Writable resources have been changed to take a `BufView` instead of a `ZeroCopyBuf` as an argument. This allows for less copying of data in certain scenarios, as described above. Additionally a new `Resource::write_all` method has been added that takes a `BufView` and continually attempts to write the resource until the entire buffer has been written. Certain resources like files can override this method to provide a more efficient `write_all` implementation.
2022-10-09 10:49:25 -04:00
self: Rc<Self>,
atime_secs: i64,
atime_nanos: u32,
mtime_secs: i64,
mtime_nanos: u32,
) -> FsResult<()> {
let atime = filetime::FileTime::from_unix_time(atime_secs, atime_nanos);
let mtime = filetime::FileTime::from_unix_time(mtime_secs, mtime_nanos);
self
.with_inner_blocking_task(move |file| {
filetime::set_file_handle_times(file, Some(atime), Some(mtime))?;
Ok(())
})
.await
}
async fn read_byob(
self: Rc<Self>,
mut buf: BufMutView,
) -> FsResult<(usize, BufMutView)> {
match &self.kind {
/* On Windows, we need to handle special read cancellation logic for stdin */
#[cfg(windows)]
StdFileResourceKind::Stdin(state) => {
self.handle_stdin_read(state.clone(), buf).await
}
_ => {
self
.with_inner_blocking_task(|file| {
let nread = file.read(&mut buf)?;
Ok((nread, buf))
})
.await
}
}
}
fn try_clone_inner(self: Rc<Self>) -> FsResult<Rc<dyn fs::File>> {
let inner: &Option<_> = &self.cell.borrow();
match inner {
Some(inner) => Ok(Rc::new(StdFileResourceInner {
kind: self.kind.clone(),
cell: RefCell::new(Some(inner.try_clone()?)),
cell_async_task_queue: Default::default(),
handle: self.handle,
})),
None => Err(FsError::FileBusy),
}
}
fn as_stdio(self: Rc<Self>) -> FsResult<std::process::Stdio> {
match self.kind {
StdFileResourceKind::File => self.with_sync(|file| {
let file = file.try_clone()?;
Ok(file.into())
}),
_ => Ok(std::process::Stdio::inherit()),
}
}
feat(core): improve resource read & write traits (#16115) This commit introduces two new buffer wrapper types to `deno_core`. The main benefit of these new wrappers is that they can wrap a number of different underlying buffer types. This allows for a more flexible read and write API on resources that will require less copying of data between different buffer representations. - `BufView` is a read-only view onto a buffer. It can be backed by `ZeroCopyBuf`, `Vec<u8>`, and `bytes::Bytes`. - `BufViewMut` is a read-write view onto a buffer. It can be cheaply converted into a `BufView`. It can be backed by `ZeroCopyBuf` or `Vec<u8>`. Both new buffer views have a cursor. This means that the start point of the view can be constrained to write / read from just a slice of the view. Only the start point of the slice can be adjusted. The end point is fixed. To adjust the end point, the underlying buffer needs to be truncated. Readable resources have been changed to better cater to resources that do not support BYOB reads. The basic `read` method now returns a `BufView` instead of taking a `ZeroCopyBuf` to fill. This allows the operation to return buffers that the resource has already allocated, instead of forcing the caller to allocate the buffer. BYOB reads are still very useful for resources that support them, so a new `read_byob` method has been added that takes a `BufViewMut` to fill. `op_read` attempts to use `read_byob` if the resource supports it, which falls back to `read` and performs an additional copy if it does not. For Rust->JS reads this change should have no impact, but for Rust->Rust reads, this allows the caller to avoid an additional copy in many scenarios. This combined with the support for `BufView` to be backed by `bytes::Bytes` allows us to avoid one data copy when piping from a `fetch` response into an `ext/http` response. Writable resources have been changed to take a `BufView` instead of a `ZeroCopyBuf` as an argument. This allows for less copying of data in certain scenarios, as described above. Additionally a new `Resource::write_all` method has been added that takes a `BufView` and continually attempts to write the resource until the entire buffer has been written. Certain resources like files can override this method to provide a more efficient `write_all` implementation.
2022-10-09 10:49:25 -04:00
fn backing_fd(self: Rc<Self>) -> Option<ResourceHandleFd> {
Some(self.handle)
}
}
// override op_print to use the stdout and stderr in the resource table
#[op2(fast)]
pub fn op_print(
state: &mut OpState,
#[string] msg: &str,
is_err: bool,
) -> Result<(), AnyError> {
let rid = if is_err { 2 } else { 1 };
FileResource::with_file(state, rid, move |file| {
Ok(file.write_all_sync(msg.as_bytes())?)
})
}