Files
wasmtime/src/fdentry.rs
2019-09-09 11:26:06 +02:00

142 lines
3.6 KiB
Rust

use crate::sys::fdentry_impl;
use crate::{host, Error, Result};
use std::mem::ManuallyDrop;
use std::path::PathBuf;
use std::{fs, io};
#[derive(Debug)]
pub enum Descriptor {
File(fs::File),
Stdin,
Stdout,
Stderr,
}
impl Descriptor {
pub fn as_file(&self) -> Result<&fs::File> {
match self {
Descriptor::File(f) => Ok(f),
_ => Err(Error::EBADF),
}
}
pub fn is_file(&self) -> bool {
match self {
Descriptor::File(_) => true,
_ => false,
}
}
pub fn is_stdin(&self) -> bool {
match self {
Descriptor::Stdin => true,
_ => false,
}
}
pub fn is_stdout(&self) -> bool {
match self {
Descriptor::Stdout => true,
_ => false,
}
}
pub fn is_stderr(&self) -> bool {
match self {
Descriptor::Stderr => true,
_ => false,
}
}
}
#[derive(Debug)]
pub struct FdObject {
pub file_type: host::__wasi_filetype_t,
pub descriptor: ManuallyDrop<Descriptor>,
pub needs_close: bool,
// TODO: directories
}
#[derive(Debug)]
pub struct FdEntry {
pub fd_object: FdObject,
pub rights_base: host::__wasi_rights_t,
pub rights_inheriting: host::__wasi_rights_t,
pub preopen_path: Option<PathBuf>,
}
impl Drop for FdObject {
fn drop(&mut self) {
if self.needs_close {
unsafe { ManuallyDrop::drop(&mut self.descriptor) };
}
}
}
impl FdEntry {
pub fn from(file: fs::File) -> Result<Self> {
fdentry_impl::determine_type_and_access_rights(&file).map(
|(file_type, rights_base, rights_inheriting)| Self {
fd_object: FdObject {
file_type,
descriptor: ManuallyDrop::new(Descriptor::File(file)),
needs_close: true,
},
rights_base,
rights_inheriting,
preopen_path: None,
},
)
}
pub fn duplicate(file: &fs::File) -> Result<Self> {
Self::from(file.try_clone()?)
}
pub fn duplicate_stdin() -> Result<Self> {
fdentry_impl::determine_type_and_access_rights(&io::stdin()).map(
|(file_type, rights_base, rights_inheriting)| Self {
fd_object: FdObject {
file_type,
descriptor: ManuallyDrop::new(Descriptor::Stdin),
needs_close: true,
},
rights_base,
rights_inheriting,
preopen_path: None,
},
)
}
pub fn duplicate_stdout() -> Result<Self> {
fdentry_impl::determine_type_and_access_rights(&io::stdout()).map(
|(file_type, rights_base, rights_inheriting)| Self {
fd_object: FdObject {
file_type,
descriptor: ManuallyDrop::new(Descriptor::Stdout),
needs_close: true,
},
rights_base,
rights_inheriting,
preopen_path: None,
},
)
}
pub fn duplicate_stderr() -> Result<Self> {
fdentry_impl::determine_type_and_access_rights(&io::stderr()).map(
|(file_type, rights_base, rights_inheriting)| Self {
fd_object: FdObject {
file_type,
descriptor: ManuallyDrop::new(Descriptor::Stderr),
needs_close: true,
},
rights_base,
rights_inheriting,
preopen_path: None,
},
)
}
}