From 31145060b278dabc85215892e2d9e5b20c54aabe Mon Sep 17 00:00:00 2001
From: Pat Hickey <pat@moreproductive.org>
Date: Wed, 3 Feb 2021 15:04:02 -0800
Subject: [PATCH] remove virtfs - it is not suitable for use

---
 Cargo.lock                                    |  11 -
 Cargo.toml                                    |   1 -
 crates/test-programs/Cargo.toml               |   1 -
 crates/test-programs/build.rs                 |   1 -
 .../tests/wasm_tests/runtime/mod.rs           |   1 -
 .../tests/wasm_tests/runtime/virtfs.rs        |  71 ---
 crates/wasi-common/virtfs/Cargo.toml          |  19 -
 crates/wasi-common/virtfs/src/lib.rs          | 507 ------------------
 8 files changed, 612 deletions(-)
 delete mode 100644 crates/test-programs/tests/wasm_tests/runtime/virtfs.rs
 delete mode 100644 crates/wasi-common/virtfs/Cargo.toml
 delete mode 100644 crates/wasi-common/virtfs/src/lib.rs

diff --git a/Cargo.lock b/Cargo.lock
index e5616ca01c..441aaba6a2 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2806,7 +2806,6 @@ dependencies = [
  "tempfile",
  "wasi-cap-std-sync",
  "wasi-common",
- "wasi-virtfs",
  "wasmtime",
  "wasmtime-wasi",
  "wat",
@@ -3127,16 +3126,6 @@ dependencies = [
  "zeroize",
 ]
 
-[[package]]
-name = "wasi-virtfs"
-version = "0.22.0"
-dependencies = [
- "anyhow",
- "cap-std",
- "tracing",
- "wasi-common",
-]
-
 [[package]]
 name = "wasm-encoder"
 version = "0.4.0"
diff --git a/Cargo.toml b/Cargo.toml
index 376a40bea8..4321fda023 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -77,7 +77,6 @@ members = [
   "crates/wiggle/wasmtime",
   "crates/wasi-common",
   "crates/wasi-common/cap-std-sync",
-  "crates/wasi-common/virtfs",
   "examples/fib-debug/wasm",
   "examples/wasi/wasm",
   "fuzz",
diff --git a/crates/test-programs/Cargo.toml b/crates/test-programs/Cargo.toml
index 3dc15366b3..598bbc203a 100644
--- a/crates/test-programs/Cargo.toml
+++ b/crates/test-programs/Cargo.toml
@@ -12,7 +12,6 @@ cfg-if = "1.0"
 
 [dev-dependencies]
 wasi-common = { path = "../wasi-common", version = "0.22.0" }
-wasi-virtfs = { path = "../wasi-common/virtfs", version = "0.22.0" }
 wasi-cap-std-sync = { path = "../wasi-common/cap-std-sync", version = "0.22.0" }
 wasmtime = { path = "../wasmtime", version = "0.22.0" }
 wasmtime-wasi = { path = "../wasi", version = "0.22.0" }
diff --git a/crates/test-programs/build.rs b/crates/test-programs/build.rs
index 3b9273334f..6de5c1172b 100644
--- a/crates/test-programs/build.rs
+++ b/crates/test-programs/build.rs
@@ -41,7 +41,6 @@ mod wasi_tests {
         build_tests("wasi-tests", &out_dir).expect("building tests");
         test_directory(&mut out, "wasi-cap-std-sync", "cap_std_sync", &out_dir)
             .expect("generating tests");
-        test_directory(&mut out, "wasi-virtfs", "virtfs", &out_dir).expect("generating tests");
     }
 
     fn build_tests(testsuite: &str, out_dir: &Path) -> io::Result<()> {
diff --git a/crates/test-programs/tests/wasm_tests/runtime/mod.rs b/crates/test-programs/tests/wasm_tests/runtime/mod.rs
index e78d578b80..035b1e83ea 100644
--- a/crates/test-programs/tests/wasm_tests/runtime/mod.rs
+++ b/crates/test-programs/tests/wasm_tests/runtime/mod.rs
@@ -1,2 +1 @@
 pub mod cap_std_sync;
-pub mod virtfs;
diff --git a/crates/test-programs/tests/wasm_tests/runtime/virtfs.rs b/crates/test-programs/tests/wasm_tests/runtime/virtfs.rs
deleted file mode 100644
index 58ea75ae8f..0000000000
--- a/crates/test-programs/tests/wasm_tests/runtime/virtfs.rs
+++ /dev/null
@@ -1,71 +0,0 @@
-use anyhow::Context;
-use std::cell::RefCell;
-use std::path::Path;
-use std::rc::Rc;
-use wasi_common::{
-    pipe::{ReadPipe, WritePipe},
-    table::Table,
-    WasiCtx,
-};
-use wasmtime::{Linker, Module, Store};
-
-pub fn instantiate(data: &[u8], bin_name: &str, workspace: Option<&Path>) -> anyhow::Result<()> {
-    let stdout = WritePipe::new_in_memory();
-    let stderr = WritePipe::new_in_memory();
-
-    let r = {
-        let store = Store::default();
-
-        // Create our wasi context.
-        let mut builder = WasiCtx::builder(
-            wasi_cap_std_sync::random_ctx(),
-            wasi_cap_std_sync::clocks_ctx(),
-            wasi_cap_std_sync::sched_ctx(), // We shouldnt actually use this, but we will until we make a virtual scheduler
-            Rc::new(RefCell::new(Table::new())),
-        );
-
-        builder = builder
-            .arg(bin_name)?
-            .arg(".")?
-            .stdin(Box::new(ReadPipe::from(Vec::new())))
-            .stdout(Box::new(stdout.clone()))
-            .stderr(Box::new(stderr.clone()));
-
-        if workspace.is_some() {
-            let fs = wasi_virtfs::Filesystem::new(wasi_cap_std_sync::clocks_ctx().system, 420); // XXX this is duplicated - should be reference counted so I can use the same in the builder...
-            builder = builder.preopened_dir(fs.root(), ".")?;
-        }
-        let wasi = wasmtime_wasi::Wasi::new(&store, builder.build()?);
-
-        let mut linker = Linker::new(&store);
-
-        wasi.add_to_linker(&mut linker)?;
-
-        let module = Module::new(store.engine(), &data).context("failed to create wasm module")?;
-        let instance = linker.instantiate(&module)?;
-        let start = instance.get_func("_start").unwrap();
-        let with_type = start.get0::<()>()?;
-        with_type().map_err(anyhow::Error::from)
-    };
-
-    match r {
-        Ok(()) => Ok(()),
-        Err(trap) => {
-            let stdout = stdout
-                .try_into_inner()
-                .expect("sole ref to stdout")
-                .into_inner();
-            if !stdout.is_empty() {
-                println!("guest stdout:\n{}\n===", String::from_utf8_lossy(&stdout));
-            }
-            let stderr = stderr
-                .try_into_inner()
-                .expect("sole ref to stderr")
-                .into_inner();
-            if !stderr.is_empty() {
-                println!("guest stderr:\n{}\n===", String::from_utf8_lossy(&stderr));
-            }
-            Err(trap.context(format!("error while testing Wasm module '{}'", bin_name,)))
-        }
-    }
-}
diff --git a/crates/wasi-common/virtfs/Cargo.toml b/crates/wasi-common/virtfs/Cargo.toml
deleted file mode 100644
index 0be09ac1e9..0000000000
--- a/crates/wasi-common/virtfs/Cargo.toml
+++ /dev/null
@@ -1,19 +0,0 @@
-[package]
-name = "wasi-virtfs"
-version = "0.22.0"
-authors = ["The Wasmtime Project Developers"]
-description = "WASI implementation in Rust"
-license = "Apache-2.0 WITH LLVM-exception"
-categories = ["wasm"]
-keywords = ["webassembly", "wasm"]
-repository = "https://github.com/bytecodealliance/wasmtime"
-readme = "README.md"
-edition = "2018"
-include = ["src/**/*", "LICENSE" ]
-publish = false
-
-[dependencies]
-wasi-common = { path = "../", version = "0.22.0" }
-anyhow = "1.0"
-cap-std = "0.12"
-tracing = "0.1.19"
diff --git a/crates/wasi-common/virtfs/src/lib.rs b/crates/wasi-common/virtfs/src/lib.rs
deleted file mode 100644
index 52fe3652e9..0000000000
--- a/crates/wasi-common/virtfs/src/lib.rs
+++ /dev/null
@@ -1,507 +0,0 @@
-#![allow(dead_code, unused_variables, unused_imports)]
-use cap_std::time::{Duration, SystemTime};
-use std::any::Any;
-use std::cell::{Cell, Ref, RefCell, RefMut};
-use std::collections::{hash_map::Entry, HashMap};
-use std::convert::TryInto;
-use std::io::{Cursor, IoSlice, IoSliceMut, Read, Seek, SeekFrom, Write};
-use std::ops::Deref;
-use std::path::PathBuf;
-use std::rc::{Rc, Weak};
-use tracing::trace;
-use wasi_common::{
-    clocks::WasiSystemClock,
-    dir::{ReaddirCursor, ReaddirEntity, WasiDir},
-    file::{Advice, FdFlags, FileCaps, FileType, Filestat, OFlags, WasiFile},
-    Error, ErrorExt, SystemTimeSpec,
-};
-
-pub struct Filesystem {
-    // Always .get() out a Some - this is an RefCell<Option to get around a circular init problem
-    root: RefCell<Option<Rc<RefCell<DirInode>>>>,
-    clock: Box<dyn WasiSystemClock>,
-    device_id: u64,
-    next_serial: Cell<u64>,
-}
-
-impl Filesystem {
-    pub fn new(clock: Box<dyn WasiSystemClock>, device_id: u64) -> Rc<Filesystem> {
-        let now = clock.now(Duration::from_secs(0));
-        let fs = Rc::new(Filesystem {
-            root: RefCell::new(None),
-            clock,
-            device_id,
-            next_serial: Cell::new(1),
-        });
-        let root = Rc::new(RefCell::new(DirInode {
-            fs: Rc::downgrade(&fs),
-            serial: 0,
-            parent: None,
-            contents: HashMap::new(),
-            atim: now,
-            mtim: now,
-            ctim: now,
-        }));
-        fs.root.replace(Some(root.clone()));
-        fs
-    }
-    pub fn root(&self) -> Box<dyn WasiDir> {
-        Box::new(Dir(self
-            .root
-            .borrow()
-            .as_ref()
-            .expect("root option always Some after init")
-            .clone())) as Box<dyn WasiDir>
-    }
-    fn now(&self) -> SystemTime {
-        self.clock.now(Duration::from_secs(0))
-    }
-    fn fresh_serial(&self) -> u64 {
-        let s = self.next_serial.get();
-        self.next_serial.set(s + 1);
-        s
-    }
-}
-
-pub enum Inode {
-    Dir(Rc<RefCell<DirInode>>),
-    File(Rc<RefCell<FileInode>>),
-}
-
-pub struct DirInode {
-    fs: Weak<Filesystem>,
-    serial: u64,
-    parent: Option<Weak<RefCell<DirInode>>>,
-    contents: HashMap<String, Inode>,
-    atim: SystemTime,
-    mtim: SystemTime,
-    ctim: SystemTime,
-}
-
-impl DirInode {
-    pub fn fs(&self) -> Rc<Filesystem> {
-        Weak::upgrade(&self.fs).unwrap()
-    }
-}
-
-pub struct FileInode {
-    fs: Weak<Filesystem>,
-    serial: u64,
-    contents: Vec<u8>,
-    atim: SystemTime,
-    mtim: SystemTime,
-    ctim: SystemTime,
-}
-
-impl FileInode {
-    pub fn fs(&self) -> Rc<Filesystem> {
-        Weak::upgrade(&self.fs).unwrap()
-    }
-}
-
-enum FileMode {
-    ReadOnly,
-    WriteOnly,
-    ReadWrite,
-}
-
-pub struct File {
-    inode: Rc<RefCell<FileInode>>,
-    position: Cell<u64>,
-    fdflags: FdFlags,
-    mode: FileMode,
-}
-
-impl File {
-    fn is_read(&self) -> bool {
-        match self.mode {
-            FileMode::ReadOnly | FileMode::ReadWrite => true,
-            _ => false,
-        }
-    }
-    fn is_write(&self) -> bool {
-        match self.mode {
-            FileMode::WriteOnly | FileMode::ReadWrite => true,
-            _ => false,
-        }
-    }
-    fn is_append(&self) -> bool {
-        self.fdflags.contains(FdFlags::APPEND)
-    }
-    fn inode(&self) -> Ref<FileInode> {
-        self.inode.borrow()
-    }
-    fn inode_mut(&self) -> RefMut<FileInode> {
-        self.inode.borrow_mut()
-    }
-}
-
-impl WasiFile for File {
-    fn as_any(&self) -> &dyn Any {
-        self
-    }
-    fn datasync(&self) -> Result<(), Error> {
-        Ok(())
-    }
-    fn sync(&self) -> Result<(), Error> {
-        Ok(())
-    }
-    fn get_filetype(&self) -> Result<FileType, Error> {
-        Ok(FileType::RegularFile)
-    }
-    fn get_fdflags(&self) -> Result<FdFlags, Error> {
-        Ok(self.fdflags)
-    }
-    fn set_fdflags(&mut self, fdflags: FdFlags) -> Result<(), Error> {
-        self.fdflags = fdflags;
-        Ok(())
-    }
-    fn get_filestat(&self) -> Result<Filestat, Error> {
-        let inode = self.inode();
-        let fs = inode.fs();
-        Ok(Filestat {
-            device_id: fs.device_id,
-            inode: inode.serial,
-            filetype: self.get_filetype().unwrap(),
-            nlink: 0,
-            size: inode.contents.len() as u64,
-            atim: Some(inode.atim.into_std()),
-            ctim: Some(inode.ctim.into_std()),
-            mtim: Some(inode.mtim.into_std()),
-        })
-    }
-    fn set_filestat_size(&self, size: u64) -> Result<(), Error> {
-        let mut inode = self.inode.borrow_mut();
-        inode.contents.resize(size.try_into()?, 0);
-        Ok(())
-    }
-    fn advise(&self, _offset: u64, _len: u64, _advice: Advice) -> Result<(), Error> {
-        Ok(())
-    }
-    fn allocate(&self, offset: u64, len: u64) -> Result<(), Error> {
-        let mut inode = self.inode.borrow_mut();
-        let size = offset.checked_add(len).ok_or_else(|| Error::overflow())?;
-        if size > inode.contents.len() as u64 {
-            inode.contents.resize(size.try_into()?, 0);
-        }
-        Ok(())
-    }
-    fn set_times(
-        &self,
-        atime: Option<SystemTimeSpec>,
-        mtime: Option<SystemTimeSpec>,
-    ) -> Result<(), Error> {
-        let newtime = |s| match s {
-            SystemTimeSpec::SymbolicNow => self.inode().fs().clock.now(Duration::from_secs(0)),
-            SystemTimeSpec::Absolute(t) => t,
-        };
-        let mut inode = self.inode.borrow_mut();
-        if let Some(atim) = atime {
-            inode.atim = newtime(atim);
-        }
-        if let Some(mtim) = mtime {
-            inode.mtim = newtime(mtim);
-        }
-        Ok(())
-    }
-    fn read_vectored(&self, bufs: &mut [IoSliceMut]) -> Result<u64, Error> {
-        if !self.is_read() {
-            return Err(Error::badf());
-        }
-        let inode = self.inode();
-        let mut cursor = Cursor::new(inode.contents.as_slice());
-        cursor.set_position(self.position.get());
-        let nbytes = cursor.read_vectored(bufs)?;
-        self.position.set(cursor.position());
-        Ok(nbytes.try_into()?)
-    }
-    fn read_vectored_at(&self, bufs: &mut [IoSliceMut], offset: u64) -> Result<u64, Error> {
-        if !self.is_read() {
-            return Err(Error::badf());
-        }
-        let inode = self.inode();
-        let mut cursor = Cursor::new(inode.contents.as_slice());
-        cursor.set_position(offset);
-        let nbytes = cursor.read_vectored(bufs)?;
-        Ok(nbytes.try_into()?)
-    }
-    fn write_vectored(&self, bufs: &[IoSlice]) -> Result<u64, Error> {
-        if !self.is_write() {
-            return Err(Error::badf());
-        }
-        let mut inode = self.inode_mut();
-        let mut cursor = Cursor::new(&mut inode.contents);
-        cursor.set_position(self.position.get());
-        let nbytes = cursor.write_vectored(bufs)?;
-        self.position.set(cursor.position());
-        Ok(nbytes.try_into()?)
-    }
-    fn write_vectored_at(&self, bufs: &[IoSlice], offset: u64) -> Result<u64, Error> {
-        if !self.is_write() || self.is_append() {
-            return Err(Error::badf());
-        }
-        let mut inode = self.inode_mut();
-        let mut cursor = Cursor::new(&mut inode.contents);
-        cursor.set_position(offset);
-        let nbytes = cursor.write_vectored(bufs)?;
-        self.position.set(cursor.position());
-        Ok(nbytes.try_into()?)
-    }
-    fn seek(&self, pos: SeekFrom) -> Result<u64, Error> {
-        if self.is_append() {
-            match pos {
-                SeekFrom::Current(0) => return Ok(self.position.get()),
-                _ => return Err(Error::badf()),
-            }
-        }
-        let inode = self.inode();
-        let mut cursor = Cursor::new(inode.contents.as_slice());
-        cursor.set_position(self.position.get());
-        cursor.seek(pos)?;
-        let new_position = cursor.position();
-        self.position.set(new_position);
-        Ok(new_position)
-    }
-    fn peek(&self, buf: &mut [u8]) -> Result<u64, Error> {
-        if !self.is_read() {
-            return Err(Error::badf());
-        }
-        let inode = self.inode();
-        let mut cursor = Cursor::new(inode.contents.as_slice());
-        cursor.set_position(self.position.get());
-        let nbytes = cursor.read(buf)?;
-        Ok(nbytes.try_into()?)
-    }
-    fn num_ready_bytes(&self) -> Result<u64, Error> {
-        if !self.is_read() {
-            return Err(Error::badf());
-        }
-        let len = self.inode().contents.len() as u64;
-        Ok(len - self.position.get())
-    }
-}
-
-pub struct Dir(Rc<RefCell<DirInode>>);
-
-impl Dir {
-    fn at_path<F, A>(&self, path: &str, accept_trailing_slash: bool, f: F) -> Result<A, Error>
-    where
-        F: FnOnce(&Dir, &str) -> Result<A, Error>,
-    {
-        // Doesnt even attempt to deal with trailing slashes
-        if let Some(slash_index) = path.find('/') {
-            let dirname = &path[..slash_index];
-            let rest = &path[slash_index + 1..];
-            if rest == "" {
-                if accept_trailing_slash {
-                    return f(self, path);
-                } else {
-                    return Err(Error::invalid_argument()
-                        .context("empty filename, probably related to trailing slashes"));
-                }
-            }
-            if let Some(inode) = self.0.borrow().contents.get(dirname) {
-                match inode {
-                    Inode::Dir(d) => Dir(d.clone()).at_path(rest, accept_trailing_slash, f),
-                    Inode::File { .. } => Err(Error::not_found()),
-                }
-            } else {
-                Err(Error::not_found())
-            }
-        } else {
-            f(self, path)
-        }
-    }
-    fn child_dir(&self, name: &str) -> Result<Rc<RefCell<DirInode>>, Error> {
-        if name == "." {
-            return Ok(self.0.clone());
-        }
-        match self.0.borrow().contents.get(name) {
-            Some(Inode::Dir(d)) => Ok(d.clone()),
-            _ => Err(Error::not_found()),
-        }
-    }
-    fn child_file(&self, name: &str) -> Result<Rc<RefCell<FileInode>>, Error> {
-        match self.0.borrow().contents.get(name) {
-            Some(Inode::File(f)) => Ok(f.clone()),
-            _ => Err(Error::not_found()),
-        }
-    }
-}
-
-impl WasiDir for Dir {
-    fn as_any(&self) -> &dyn Any {
-        self
-    }
-    fn open_file(
-        &self,
-        _symlink_follow: bool,
-        path: &str,
-        oflags: OFlags,
-        read: bool,
-        write: bool,
-        fdflags: FdFlags,
-    ) -> Result<Box<dyn WasiFile>, Error> {
-        let mode = if read && write {
-            FileMode::ReadWrite
-        } else if write {
-            FileMode::WriteOnly
-        } else {
-            FileMode::ReadOnly
-        };
-        // XXX TERRIBLE CODE DUPLICATION HERE
-        self.at_path(path, false, |dir, filename| {
-            if oflags.contains(OFlags::CREATE | OFlags::EXCLUSIVE) {
-                match dir.child_file(filename) {
-                    Err(_notfound) => {
-                        let d = dir.0.borrow();
-                        let now = d.fs().now();
-                        let serial = d.fs().fresh_serial();
-                        let inode = Rc::new(RefCell::new(FileInode {
-                            fs: d.fs.clone(),
-                            serial,
-                            contents: Vec::new(),
-                            atim: now,
-                            ctim: now,
-                            mtim: now,
-                        }));
-                        dir.0
-                            .borrow_mut()
-                            .contents
-                            .insert(filename.to_owned(), Inode::File(inode.clone()));
-                        Ok(Box::new(File {
-                            inode,
-                            position: Cell::new(0),
-                            fdflags,
-                            mode,
-                        }) as Box<dyn WasiFile>)
-                    }
-                    Ok(_) => Err(Error::exist()),
-                }
-            } else if oflags.contains(OFlags::CREATE) {
-                match dir.child_file(filename) {
-                    Ok(inode) => {
-                        // XXX update atime here!
-                        Ok(Box::new(File {
-                            inode,
-                            position: Cell::new(0),
-                            fdflags,
-                            mode,
-                        }) as Box<dyn WasiFile>)
-                    }
-                    Err(_notfound) => {
-                        let d = dir.0.borrow();
-                        let now = d.fs().now();
-                        let serial = d.fs().fresh_serial();
-                        let inode = Rc::new(RefCell::new(FileInode {
-                            fs: d.fs.clone(),
-                            serial,
-                            contents: Vec::new(),
-                            atim: now,
-                            ctim: now,
-                            mtim: now,
-                        }));
-                        dir.0
-                            .borrow_mut()
-                            .contents
-                            .insert(filename.to_owned(), Inode::File(inode.clone()));
-                        Ok(Box::new(File {
-                            inode,
-                            position: Cell::new(0),
-                            fdflags,
-                            mode,
-                        }) as Box<dyn WasiFile>)
-                    }
-                }
-            } else {
-                let inode = dir.child_file(filename)?;
-                // XXX update atime here!
-                Ok(Box::new(File {
-                    inode,
-                    position: Cell::new(0),
-                    fdflags,
-                    mode,
-                }) as Box<dyn WasiFile>)
-            }
-        })
-    }
-
-    fn open_dir(&self, _symlink_follow: bool, path: &str) -> Result<Box<dyn WasiDir>, Error> {
-        self.at_path(path, true, |dir, dirname| {
-            let d = dir.child_dir(dirname)?;
-            Ok(Box::new(Dir(d)) as Box<dyn WasiDir>)
-        })
-    }
-
-    fn create_dir(&self, path: &str) -> Result<(), Error> {
-        self.at_path(path, true, |dir, dirname| {
-            let d = dir.0.borrow();
-            let fs = d.fs.clone();
-            let serial = d.fs().fresh_serial();
-            let now = d.fs().now();
-            drop(d);
-            match dir.0.borrow_mut().contents.entry(dirname.to_owned()) {
-                Entry::Vacant(v) => {
-                    let parent = Some(Rc::downgrade(&self.0));
-                    v.insert(Inode::Dir(Rc::new(RefCell::new(DirInode {
-                        fs,
-                        serial,
-                        parent,
-                        contents: HashMap::new(),
-                        atim: now,
-                        mtim: now,
-                        ctim: now,
-                    }))));
-                    Ok(())
-                }
-                Entry::Occupied(_) => Err(Error::exist()),
-            }
-        })
-    }
-    fn readdir(
-        &self,
-        cursor: ReaddirCursor,
-    ) -> Result<Box<dyn Iterator<Item = Result<(ReaddirEntity, String), Error>>>, Error> {
-        todo!()
-    }
-
-    fn symlink(&self, src_path: &str, dest_path: &str) -> Result<(), Error> {
-        todo!()
-    }
-    fn remove_dir(&self, path: &str) -> Result<(), Error> {
-        todo!()
-    }
-
-    fn unlink_file(&self, path: &str) -> Result<(), Error> {
-        todo!()
-    }
-    fn read_link(&self, path: &str) -> Result<PathBuf, Error> {
-        todo!()
-    }
-    fn get_filestat(&self) -> Result<Filestat, Error> {
-        todo!()
-    }
-    fn get_path_filestat(&self, path: &str, follow_symlinks: bool) -> Result<Filestat, Error> {
-        todo!()
-    }
-    fn rename(&self, src_path: &str, dest_dir: &dyn WasiDir, dest_path: &str) -> Result<(), Error> {
-        todo!()
-    }
-    fn hard_link(
-        &self,
-        src_path: &str,
-        target_dir: &dyn WasiDir,
-        target_path: &str,
-    ) -> Result<(), Error> {
-        todo!()
-    }
-    fn set_times(
-        &self,
-        path: &str,
-        atime: Option<wasi_common::SystemTimeSpec>,
-        mtime: Option<wasi_common::SystemTimeSpec>,
-        follow_symlinks: bool,
-    ) -> Result<(), Error> {
-        todo!()
-    }
-}