1
0
Fork 0
mirror of https://github.com/denoland/deno.git synced 2025-01-16 19:04:02 -05:00
denoland-deno/src/files.rs
Ryan Dahl bcbbee7399 Adds basic File I/O and FD table.
Adds deno.stdin, deno.stdout, deno.stderr, deno.open(), deno.write(),
deno.read(), deno.Reader, deno.Writer, deno.copy().

Fixes #721. tests/cat.ts works.
2018-09-28 20:53:33 -04:00

119 lines
3.2 KiB
Rust

// Copyright 2018 the Deno authors. All rights reserved. MIT license.
use futures;
use futures::Poll;
use std;
use std::collections::HashMap;
use std::io::Error;
use std::io::{Read, Write};
use std::sync::atomic::AtomicIsize;
use std::sync::atomic::Ordering;
use std::sync::Mutex;
use tokio;
use tokio::io::{AsyncRead, AsyncWrite};
// These store Deno's file descriptors. These are not necessarally the operating
// system ones.
type FdTable = HashMap<i32, Repr>;
lazy_static! {
// Starts at 3 because stdio is [0-2].
static ref NEXT_FD: AtomicIsize = AtomicIsize::new(3);
static ref FD_TABLE: Mutex<FdTable> = Mutex::new({
let mut m = HashMap::new();
// TODO Load these lazily during lookup?
m.insert(0, Repr::Stdin(tokio::io::stdin()));
m.insert(1, Repr::Stdout(tokio::io::stdout()));
m.insert(2, Repr::Stderr(tokio::io::stderr()));
m
});
}
// Internal representation of DFile.
enum Repr {
Stdin(tokio::io::Stdin),
Stdout(tokio::io::Stdout),
Stderr(tokio::io::Stderr),
FsFile(tokio::fs::File),
}
// Abstract async file interface.
// fd does not necessarally correspond to an OS fd.
// Ideally in unix, if DFile represents an OS fd, it will be the same.
pub struct DFile {
pub fd: i32,
}
impl Read for DFile {
fn read(&mut self, _buf: &mut [u8]) -> std::io::Result<usize> {
unimplemented!();
}
}
impl AsyncRead for DFile {
fn poll_read(&mut self, buf: &mut [u8]) -> Poll<usize, Error> {
let mut table = FD_TABLE.lock().unwrap();
let maybe_repr = table.get_mut(&self.fd);
match maybe_repr {
None => panic!("bad fd"),
Some(repr) => match repr {
Repr::FsFile(ref mut f) => f.poll_read(buf),
Repr::Stdin(ref mut f) => f.poll_read(buf),
Repr::Stdout(_) | Repr::Stderr(_) => {
panic!("Cannot read from stdout/stderr")
}
},
}
}
}
impl Write for DFile {
fn write(&mut self, _buf: &[u8]) -> std::io::Result<usize> {
unimplemented!()
}
fn flush(&mut self) -> std::io::Result<()> {
unimplemented!()
}
}
impl AsyncWrite for DFile {
fn poll_write(&mut self, buf: &[u8]) -> Poll<usize, Error> {
let mut table = FD_TABLE.lock().unwrap();
let maybe_repr = table.get_mut(&self.fd);
match maybe_repr {
None => panic!("bad fd"),
Some(repr) => match repr {
Repr::FsFile(ref mut f) => f.poll_write(buf),
Repr::Stdout(ref mut f) => f.poll_write(buf),
Repr::Stderr(ref mut f) => f.poll_write(buf),
Repr::Stdin(_) => panic!("Cannot write to stdin"),
},
}
}
fn shutdown(&mut self) -> futures::Poll<(), std::io::Error> {
unimplemented!()
}
}
fn new_fd() -> i32 {
// TODO If on unix, just extract the real FD of fs_file.
// let fd = AsRawFd::as_raw_fd(fs_file.std());
let next_fd = NEXT_FD.fetch_add(1, Ordering::SeqCst);
next_fd as i32
}
pub fn add_fs_file(fs_file: tokio::fs::File) -> DFile {
let fd = new_fd();
let mut tg = FD_TABLE.lock().unwrap();
match tg.insert(fd, Repr::FsFile(fs_file)) {
Some(_) => panic!("There is already a file with that fd"),
None => DFile { fd },
}
}
pub fn lookup(fd: i32) -> Option<DFile> {
let table = FD_TABLE.lock().unwrap();
table.get(&fd).map(|_| DFile { fd })
}