Trait wasi_common::dir::WasiDir

source · 
pub trait WasiDir: Send + Sync {

Show 14 methods    fn as_any(&self) -> &dyn Any;

    fn open_file<'life0, 'life1, 'async_trait>(
        &'life0 self,
        _symlink_follow: bool,
        _path: &'life1 str,
        _oflags: OFlags,
        _read: bool,
        _write: bool,
        _fdflags: FdFlags
    ) -> Pin<Box<dyn Future<Output = Result<Box<dyn WasiFile>, Error>> + Send + 'async_trait>>
    where
        Self: 'async_trait,
        'life0: 'async_trait,
        'life1: 'async_trait,
    { ... }
    fn open_dir<'life0, 'life1, 'async_trait>(
        &'life0 self,
        _symlink_follow: bool,
        _path: &'life1 str
    ) -> Pin<Box<dyn Future<Output = Result<Box<dyn WasiDir>, Error>> + Send + 'async_trait>>
    where
        Self: 'async_trait,
        'life0: 'async_trait,
        'life1: 'async_trait,
    { ... }
    fn create_dir<'life0, 'life1, 'async_trait>(
        &'life0 self,
        _path: &'life1 str
    ) -> Pin<Box<dyn Future<Output = Result<(), Error>> + Send + 'async_trait>>
    where
        Self: 'async_trait,
        'life0: 'async_trait,
        'life1: 'async_trait,
    { ... }
    fn readdir<'life0, 'async_trait>(
        &'life0 self,
        _cursor: ReaddirCursor
    ) -> Pin<Box<dyn Future<Output = Result<Box<dyn Iterator<Item = Result<ReaddirEntity, Error>> + Send>, Error>> + Send + 'async_trait>>
    where
        Self: 'async_trait,
        'life0: 'async_trait,
    { ... }
    fn symlink<'life0, 'life1, 'life2, 'async_trait>(
        &'life0 self,
        _old_path: &'life1 str,
        _new_path: &'life2 str
    ) -> Pin<Box<dyn Future<Output = Result<(), Error>> + Send + 'async_trait>>
    where
        Self: 'async_trait,
        'life0: 'async_trait,
        'life1: 'async_trait,
        'life2: 'async_trait,
    { ... }
    fn remove_dir<'life0, 'life1, 'async_trait>(
        &'life0 self,
        _path: &'life1 str
    ) -> Pin<Box<dyn Future<Output = Result<(), Error>> + Send + 'async_trait>>
    where
        Self: 'async_trait,
        'life0: 'async_trait,
        'life1: 'async_trait,
    { ... }
    fn unlink_file<'life0, 'life1, 'async_trait>(
        &'life0 self,
        _path: &'life1 str
    ) -> Pin<Box<dyn Future<Output = Result<(), Error>> + Send + 'async_trait>>
    where
        Self: 'async_trait,
        'life0: 'async_trait,
        'life1: 'async_trait,
    { ... }
    fn read_link<'life0, 'life1, 'async_trait>(
        &'life0 self,
        _path: &'life1 str
    ) -> Pin<Box<dyn Future<Output = Result<PathBuf, Error>> + Send + 'async_trait>>
    where
        Self: 'async_trait,
        'life0: 'async_trait,
        'life1: 'async_trait,
    { ... }
    fn get_filestat<'life0, 'async_trait>(
        &'life0 self
    ) -> Pin<Box<dyn Future<Output = Result<Filestat, Error>> + Send + 'async_trait>>
    where
        Self: 'async_trait,
        'life0: 'async_trait,
    { ... }
    fn get_path_filestat<'life0, 'life1, 'async_trait>(
        &'life0 self,
        _path: &'life1 str,
        _follow_symlinks: bool
    ) -> Pin<Box<dyn Future<Output = Result<Filestat, Error>> + Send + 'async_trait>>
    where
        Self: 'async_trait,
        'life0: 'async_trait,
        'life1: 'async_trait,
    { ... }
    fn rename<'life0, 'life1, 'life2, 'life3, 'async_trait>(
        &'life0 self,
        _path: &'life1 str,
        _dest_dir: &'life2 dyn WasiDir,
        _dest_path: &'life3 str
    ) -> Pin<Box<dyn Future<Output = Result<(), Error>> + Send + 'async_trait>>
    where
        Self: 'async_trait,
        'life0: 'async_trait,
        'life1: 'async_trait,
        'life2: 'async_trait,
        'life3: 'async_trait,
    { ... }
    fn hard_link<'life0, 'life1, 'life2, 'life3, 'async_trait>(
        &'life0 self,
        _path: &'life1 str,
        _target_dir: &'life2 dyn WasiDir,
        _target_path: &'life3 str
    ) -> Pin<Box<dyn Future<Output = Result<(), Error>> + Send + 'async_trait>>
    where
        Self: 'async_trait,
        'life0: 'async_trait,
        'life1: 'async_trait,
        'life2: 'async_trait,
        'life3: 'async_trait,
    { ... }
    fn set_times<'life0, 'life1, 'async_trait>(
        &'life0 self,
        _path: &'life1 str,
        _atime: Option<SystemTimeSpec>,
        _mtime: Option<SystemTimeSpec>,
        _follow_symlinks: bool
    ) -> Pin<Box<dyn Future<Output = Result<(), Error>> + Send + 'async_trait>>
    where
        Self: 'async_trait,
        'life0: 'async_trait,
        'life1: 'async_trait,
    { ... }

}

Required Methods§

Provided Methods§

Examples found in repository?
src/snapshots/preview_1.rs (line 711)
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    async fn path_open<'a>(
        &mut self,
        dirfd: types::Fd,
        dirflags: types::Lookupflags,
        path: &GuestPtr<'a, str>,
        oflags: types::Oflags,
        fs_rights_base: types::Rights,
        fs_rights_inheriting: types::Rights,
        fdflags: types::Fdflags,
    ) -> Result<types::Fd, Error> {
        let table = self.table();
        let dirfd = u32::from(dirfd);
        if table.is::<FileEntry>(dirfd) {
            return Err(Error::not_dir());
        }
        let dir_entry = table.get_dir(dirfd)?;

        let symlink_follow = dirflags.contains(types::Lookupflags::SYMLINK_FOLLOW);

        let oflags = OFlags::from(&oflags);
        let fdflags = FdFlags::from(fdflags);
        let path = path.as_str()?.expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)");
        if oflags.contains(OFlags::DIRECTORY) {
            if oflags.contains(OFlags::CREATE)
                || oflags.contains(OFlags::EXCLUSIVE)
                || oflags.contains(OFlags::TRUNCATE)
            {
                return Err(Error::invalid_argument().context("directory oflags"));
            }
            let dir_caps = dir_entry.child_dir_caps(DirCaps::from(&fs_rights_base));
            let file_caps = dir_entry.child_file_caps(FileCaps::from(&fs_rights_inheriting));
            let dir = dir_entry.get_cap(DirCaps::OPEN)?;
            let child_dir = dir.open_dir(symlink_follow, path.deref()).await?;
            drop(dir);
            let fd = table.push(Box::new(DirEntry::new(
                dir_caps, file_caps, None, child_dir,
            )))?;
            Ok(types::Fd::from(fd))
        } else {
            let mut required_caps = DirCaps::OPEN;
            if oflags.contains(OFlags::CREATE) {
                required_caps = required_caps | DirCaps::CREATE_FILE;
            }

            let file_caps = dir_entry.child_file_caps(FileCaps::from(&fs_rights_base));
            let dir = dir_entry.get_cap(required_caps)?;
            let read = file_caps.contains(FileCaps::READ);
            let write = file_caps.contains(FileCaps::WRITE)
                || file_caps.contains(FileCaps::ALLOCATE)
                || file_caps.contains(FileCaps::FILESTAT_SET_SIZE);
            let file = dir
                .open_file(symlink_follow, path.deref(), oflags, read, write, fdflags)
                .await?;
            drop(dir);
            let fd = table.push(Box::new(FileEntry::new(file_caps, file)))?;
            Ok(types::Fd::from(fd))
        }
    }
Examples found in repository?
src/snapshots/preview_1.rs (line 692)
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    async fn path_open<'a>(
        &mut self,
        dirfd: types::Fd,
        dirflags: types::Lookupflags,
        path: &GuestPtr<'a, str>,
        oflags: types::Oflags,
        fs_rights_base: types::Rights,
        fs_rights_inheriting: types::Rights,
        fdflags: types::Fdflags,
    ) -> Result<types::Fd, Error> {
        let table = self.table();
        let dirfd = u32::from(dirfd);
        if table.is::<FileEntry>(dirfd) {
            return Err(Error::not_dir());
        }
        let dir_entry = table.get_dir(dirfd)?;

        let symlink_follow = dirflags.contains(types::Lookupflags::SYMLINK_FOLLOW);

        let oflags = OFlags::from(&oflags);
        let fdflags = FdFlags::from(fdflags);
        let path = path.as_str()?.expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)");
        if oflags.contains(OFlags::DIRECTORY) {
            if oflags.contains(OFlags::CREATE)
                || oflags.contains(OFlags::EXCLUSIVE)
                || oflags.contains(OFlags::TRUNCATE)
            {
                return Err(Error::invalid_argument().context("directory oflags"));
            }
            let dir_caps = dir_entry.child_dir_caps(DirCaps::from(&fs_rights_base));
            let file_caps = dir_entry.child_file_caps(FileCaps::from(&fs_rights_inheriting));
            let dir = dir_entry.get_cap(DirCaps::OPEN)?;
            let child_dir = dir.open_dir(symlink_follow, path.deref()).await?;
            drop(dir);
            let fd = table.push(Box::new(DirEntry::new(
                dir_caps, file_caps, None, child_dir,
            )))?;
            Ok(types::Fd::from(fd))
        } else {
            let mut required_caps = DirCaps::OPEN;
            if oflags.contains(OFlags::CREATE) {
                required_caps = required_caps | DirCaps::CREATE_FILE;
            }

            let file_caps = dir_entry.child_file_caps(FileCaps::from(&fs_rights_base));
            let dir = dir_entry.get_cap(required_caps)?;
            let read = file_caps.contains(FileCaps::READ);
            let write = file_caps.contains(FileCaps::WRITE)
                || file_caps.contains(FileCaps::ALLOCATE)
                || file_caps.contains(FileCaps::FILESTAT_SET_SIZE);
            let file = dir
                .open_file(symlink_follow, path.deref(), oflags, read, write, fdflags)
                .await?;
            drop(dir);
            let fd = table.push(Box::new(FileEntry::new(file_caps, file)))?;
            Ok(types::Fd::from(fd))
        }
    }
Examples found in repository?
src/snapshots/preview_1.rs (line 580)
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    async fn path_create_directory<'a>(
        &mut self,
        dirfd: types::Fd,
        path: &GuestPtr<'a, str>,
    ) -> Result<(), Error> {
        self.table()
            .get_dir(u32::from(dirfd))?
            .get_cap(DirCaps::CREATE_DIRECTORY)?
            .create_dir(path.as_str()?.expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)").deref())
            .await
    }
Examples found in repository?
src/snapshots/preview_1.rs (line 531)
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    async fn fd_readdir<'a>(
        &mut self,
        fd: types::Fd,
        buf: &GuestPtr<'a, u8>,
        buf_len: types::Size,
        cookie: types::Dircookie,
    ) -> Result<types::Size, Error> {
        let mut bufused = 0;
        let mut buf = buf.clone();
        for entity in self
            .table()
            .get_dir(u32::from(fd))?
            .get_cap(DirCaps::READDIR)?
            .readdir(ReaddirCursor::from(cookie))
            .await?
        {
            let entity = entity?;
            let dirent_raw = dirent_bytes(types::Dirent::try_from(&entity)?);
            let dirent_len: types::Size = dirent_raw.len().try_into()?;
            let name_raw = entity.name.as_bytes();
            let name_len: types::Size = name_raw.len().try_into()?;

            // Copy as many bytes of the dirent as we can, up to the end of the buffer
            let dirent_copy_len = std::cmp::min(dirent_len, buf_len - bufused);
            buf.as_array(dirent_copy_len)
                .copy_from_slice(&dirent_raw[..dirent_copy_len as usize])?;

            // If the dirent struct wasnt compied entirely, return that we filled the buffer, which
            // tells libc that we're not at EOF.
            if dirent_copy_len < dirent_len {
                return Ok(buf_len);
            }

            buf = buf.add(dirent_copy_len)?;
            bufused += dirent_copy_len;

            // Copy as many bytes of the name as we can, up to the end of the buffer
            let name_copy_len = std::cmp::min(name_len, buf_len - bufused);
            buf.as_array(name_copy_len)
                .copy_from_slice(&name_raw[..name_copy_len as usize])?;

            // If the dirent struct wasn't copied entirely, return that we filled the buffer, which
            // tells libc that we're not at EOF

            if name_copy_len < name_len {
                return Ok(buf_len);
            }

            buf = buf.add(name_copy_len)?;
            bufused += name_copy_len;
        }
        Ok(bufused)
    }
Examples found in repository?
src/snapshots/preview_1.rs (line 792)
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    async fn path_symlink<'a>(
        &mut self,
        src_path: &GuestPtr<'a, str>,
        dirfd: types::Fd,
        dest_path: &GuestPtr<'a, str>,
    ) -> Result<(), Error> {
        self.table()
            .get_dir(u32::from(dirfd))?
            .get_cap(DirCaps::SYMLINK)?
            .symlink(src_path.as_str()?.expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)").deref(), dest_path.as_str()?.expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)").deref())
            .await
    }
Examples found in repository?
src/snapshots/preview_1.rs (line 756)
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    async fn path_remove_directory<'a>(
        &mut self,
        dirfd: types::Fd,
        path: &GuestPtr<'a, str>,
    ) -> Result<(), Error> {
        self.table()
            .get_dir(u32::from(dirfd))?
            .get_cap(DirCaps::REMOVE_DIRECTORY)?
            .remove_dir(path.as_str()?.expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)").deref())
            .await
    }
Examples found in repository?
src/snapshots/preview_1.rs (lines 804-805)
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    async fn path_unlink_file<'a>(
        &mut self,
        dirfd: types::Fd,
        path: &GuestPtr<'a, str>,
    ) -> Result<(), Error> {
        self.table()
            .get_dir(u32::from(dirfd))?
            .get_cap(DirCaps::UNLINK_FILE)?
            .unlink_file(path.as_str()?
            .expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)").deref())
            .await
    }
Examples found in repository?
src/snapshots/preview_1.rs (line 730)
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    async fn path_readlink<'a>(
        &mut self,
        dirfd: types::Fd,
        path: &GuestPtr<'a, str>,
        buf: &GuestPtr<'a, u8>,
        buf_len: types::Size,
    ) -> Result<types::Size, Error> {
        let link = self
            .table()
            .get_dir(u32::from(dirfd))?
            .get_cap(DirCaps::READLINK)?
            .read_link(path.as_str()?.expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)").deref())
            .await?
            .into_os_string()
            .into_string()
            .map_err(|_| Error::illegal_byte_sequence().context("link contents"))?;
        let link_bytes = link.as_bytes();
        let link_len = link_bytes.len();
        if link_len > buf_len as usize {
            return Err(Error::range());
        }
        let mut buf = buf
            .as_array(link_len as u32)
            .as_slice_mut()?
            .expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)");
        buf.copy_from_slice(link_bytes);
        Ok(link_len as types::Size)
    }
Examples found in repository?
src/snapshots/preview_1.rs (line 230)
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    async fn fd_filestat_get(&mut self, fd: types::Fd) -> Result<types::Filestat, Error> {
        let table = self.table();
        let fd = u32::from(fd);
        if table.is::<FileEntry>(fd) {
            let filestat = table
                .get_file_mut(fd)?
                .get_cap_mut(FileCaps::FILESTAT_GET)?
                .get_filestat()
                .await?;
            Ok(filestat.into())
        } else if table.is::<DirEntry>(fd) {
            let filestat = table
                .get_dir(fd)?
                .get_cap(DirCaps::FILESTAT_GET)?
                .get_filestat()
                .await?;
            Ok(filestat.into())
        } else {
            Err(Error::badf())
        }
    }
Examples found in repository?
src/snapshots/preview_1.rs (lines 594-597)
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    async fn path_filestat_get<'a>(
        &mut self,
        dirfd: types::Fd,
        flags: types::Lookupflags,
        path: &GuestPtr<'a, str>,
    ) -> Result<types::Filestat, Error> {
        let filestat = self
            .table()
            .get_dir(u32::from(dirfd))?
            .get_cap(DirCaps::PATH_FILESTAT_GET)?
            .get_path_filestat(
                path.as_str()?.expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)").deref(),
                flags.contains(types::Lookupflags::SYMLINK_FOLLOW),
            )
            .await?;
        Ok(types::Filestat::from(filestat))
    }
Examples found in repository?
src/snapshots/preview_1.rs (lines 775-779)
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    async fn path_rename<'a>(
        &mut self,
        src_fd: types::Fd,
        src_path: &GuestPtr<'a, str>,
        dest_fd: types::Fd,
        dest_path: &GuestPtr<'a, str>,
    ) -> Result<(), Error> {
        let table = self.table();
        let src_dir = table
            .get_dir(u32::from(src_fd))?
            .get_cap(DirCaps::RENAME_SOURCE)?;
        let dest_dir = table
            .get_dir(u32::from(dest_fd))?
            .get_cap(DirCaps::RENAME_TARGET)?;
        src_dir
            .rename(
                src_path.as_str()?.expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)").deref(),
                dest_dir.deref(),
                dest_path.as_str()?.expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)").deref(),
            )
            .await
    }
Examples found in repository?
src/snapshots/preview_1.rs (lines 652-656)
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    async fn path_link<'a>(
        &mut self,
        src_fd: types::Fd,
        src_flags: types::Lookupflags,
        src_path: &GuestPtr<'a, str>,
        target_fd: types::Fd,
        target_path: &GuestPtr<'a, str>,
    ) -> Result<(), Error> {
        let table = self.table();
        let src_dir = table
            .get_dir(u32::from(src_fd))?
            .get_cap(DirCaps::LINK_SOURCE)?;
        let target_dir = table
            .get_dir(u32::from(target_fd))?
            .get_cap(DirCaps::LINK_TARGET)?;
        let symlink_follow = src_flags.contains(types::Lookupflags::SYMLINK_FOLLOW);
        if symlink_follow {
            return Err(Error::invalid_argument()
                .context("symlink following on path_link is not supported"));
        }

        src_dir
            .hard_link(
                src_path.as_str()?.expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)").deref(),
                target_dir.deref(),
                target_path.as_str()?.expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)").deref(),
            )
            .await
    }
Examples found in repository?
src/snapshots/preview_1.rs (line 281)
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    async fn fd_filestat_set_times(
        &mut self,
        fd: types::Fd,
        atim: types::Timestamp,
        mtim: types::Timestamp,
        fst_flags: types::Fstflags,
    ) -> Result<(), Error> {
        let fd = u32::from(fd);
        let table = self.table();
        // Validate flags
        let set_atim = fst_flags.contains(types::Fstflags::ATIM);
        let set_atim_now = fst_flags.contains(types::Fstflags::ATIM_NOW);
        let set_mtim = fst_flags.contains(types::Fstflags::MTIM);
        let set_mtim_now = fst_flags.contains(types::Fstflags::MTIM_NOW);

        let atim = systimespec(set_atim, atim, set_atim_now).map_err(|e| e.context("atim"))?;
        let mtim = systimespec(set_mtim, mtim, set_mtim_now).map_err(|e| e.context("mtim"))?;

        if table.is::<FileEntry>(fd) {
            table
                .get_file_mut(fd)
                .expect("checked that entry is file")
                .get_cap_mut(FileCaps::FILESTAT_SET_TIMES)?
                .set_times(atim, mtim)
                .await
        } else if table.is::<DirEntry>(fd) {
            table
                .get_dir(fd)
                .expect("checked that entry is dir")
                .get_cap(DirCaps::FILESTAT_SET_TIMES)?
                .set_times(".", atim, mtim, false)
                .await
        } else {
            Err(Error::badf())
        }
    }

    async fn fd_read<'a>(
        &mut self,
        fd: types::Fd,
        iovs: &types::IovecArray<'a>,
    ) -> Result<types::Size, Error> {
        let f = self
            .table()
            .get_file_mut(u32::from(fd))?
            .get_cap_mut(FileCaps::READ)?;

        let mut guest_slices: Vec<wiggle::GuestSliceMut<u8>> =
            iovs.iter()
                .map(|iov_ptr| {
                    let iov_ptr = iov_ptr?;
                    let iov: types::Iovec = iov_ptr.read()?;
                    Ok(iov.buf.as_array(iov.buf_len).as_slice_mut()?.expect(
                        "cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)",
                    ))
                })
                .collect::<Result<_, Error>>()?;

        let mut ioslices: Vec<IoSliceMut> = guest_slices
            .iter_mut()
            .map(|s| IoSliceMut::new(&mut *s))
            .collect();

        let bytes_read = f.read_vectored(&mut ioslices).await?;
        Ok(types::Size::try_from(bytes_read)?)
    }

    async fn fd_pread<'a>(
        &mut self,
        fd: types::Fd,
        iovs: &types::IovecArray<'a>,
        offset: types::Filesize,
    ) -> Result<types::Size, Error> {
        let f = self
            .table()
            .get_file_mut(u32::from(fd))?
            .get_cap_mut(FileCaps::READ | FileCaps::SEEK)?;

        let mut guest_slices: Vec<wiggle::GuestSliceMut<u8>> =
            iovs.iter()
                .map(|iov_ptr| {
                    let iov_ptr = iov_ptr?;
                    let iov: types::Iovec = iov_ptr.read()?;
                    Ok(iov.buf.as_array(iov.buf_len).as_slice_mut()?.expect(
                        "cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)",
                    ))
                })
                .collect::<Result<_, Error>>()?;

        let mut ioslices: Vec<IoSliceMut> = guest_slices
            .iter_mut()
            .map(|s| IoSliceMut::new(&mut *s))
            .collect();

        let bytes_read = f.read_vectored_at(&mut ioslices, offset).await?;
        Ok(types::Size::try_from(bytes_read)?)
    }

    async fn fd_write<'a>(
        &mut self,
        fd: types::Fd,
        ciovs: &types::CiovecArray<'a>,
    ) -> Result<types::Size, Error> {
        let f = self
            .table()
            .get_file_mut(u32::from(fd))?
            .get_cap_mut(FileCaps::WRITE)?;

        let guest_slices: Vec<wiggle::GuestSlice<u8>> = ciovs
            .iter()
            .map(|iov_ptr| {
                let iov_ptr = iov_ptr?;
                let iov: types::Ciovec = iov_ptr.read()?;
                Ok(iov
                    .buf
                    .as_array(iov.buf_len)
                    .as_slice()?
                    .expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)"))
            })
            .collect::<Result<_, Error>>()?;

        let ioslices: Vec<IoSlice> = guest_slices
            .iter()
            .map(|s| IoSlice::new(s.deref()))
            .collect();
        let bytes_written = f.write_vectored(&ioslices).await?;

        Ok(types::Size::try_from(bytes_written)?)
    }

    async fn fd_pwrite<'a>(
        &mut self,
        fd: types::Fd,
        ciovs: &types::CiovecArray<'a>,
        offset: types::Filesize,
    ) -> Result<types::Size, Error> {
        let f = self
            .table()
            .get_file_mut(u32::from(fd))?
            .get_cap_mut(FileCaps::WRITE | FileCaps::SEEK)?;

        let guest_slices: Vec<wiggle::GuestSlice<u8>> = ciovs
            .iter()
            .map(|iov_ptr| {
                let iov_ptr = iov_ptr?;
                let iov: types::Ciovec = iov_ptr.read()?;
                Ok(iov
                    .buf
                    .as_array(iov.buf_len)
                    .as_slice()?
                    .expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)"))
            })
            .collect::<Result<_, Error>>()?;

        let ioslices: Vec<IoSlice> = guest_slices
            .iter()
            .map(|s| IoSlice::new(s.deref()))
            .collect();
        let bytes_written = f.write_vectored_at(&ioslices, offset).await?;

        Ok(types::Size::try_from(bytes_written)?)
    }

    async fn fd_prestat_get(&mut self, fd: types::Fd) -> Result<types::Prestat, Error> {
        let table = self.table();
        let dir_entry: &DirEntry = table.get(u32::from(fd)).map_err(|_| Error::badf())?;
        if let Some(ref preopen) = dir_entry.preopen_path() {
            let path_str = preopen.to_str().ok_or_else(|| Error::not_supported())?;
            let pr_name_len = u32::try_from(path_str.as_bytes().len())?;
            Ok(types::Prestat::Dir(types::PrestatDir { pr_name_len }))
        } else {
            Err(Error::not_supported().context("file is not a preopen"))
        }
    }

    async fn fd_prestat_dir_name<'a>(
        &mut self,
        fd: types::Fd,
        path: &GuestPtr<'a, u8>,
        path_max_len: types::Size,
    ) -> Result<(), Error> {
        let table = self.table();
        let dir_entry: &DirEntry = table.get(u32::from(fd)).map_err(|_| Error::not_dir())?;
        if let Some(ref preopen) = dir_entry.preopen_path() {
            let path_bytes = preopen
                .to_str()
                .ok_or_else(|| Error::not_supported())?
                .as_bytes();
            let path_len = path_bytes.len();
            if path_len < path_max_len as usize {
                return Err(Error::name_too_long());
            }
            let mut p_memory = path
                .as_array(path_len as u32)
                .as_slice_mut()?
                .expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)");
            p_memory.copy_from_slice(path_bytes);
            Ok(())
        } else {
            Err(Error::not_supported())
        }
    }
    async fn fd_renumber(&mut self, from: types::Fd, to: types::Fd) -> Result<(), Error> {
        let table = self.table();
        let from = u32::from(from);
        let to = u32::from(to);
        if !table.contains_key(from) {
            return Err(Error::badf());
        }
        if table.is_preopen(from) || table.is_preopen(to) {
            return Err(Error::not_supported().context("cannot renumber a preopen"));
        }
        let from_entry = table
            .delete(from)
            .expect("we checked that table contains from");
        table.insert_at(to, from_entry);
        Ok(())
    }

    async fn fd_seek(
        &mut self,
        fd: types::Fd,
        offset: types::Filedelta,
        whence: types::Whence,
    ) -> Result<types::Filesize, Error> {
        use std::io::SeekFrom;

        let required_caps = if offset == 0 && whence == types::Whence::Cur {
            FileCaps::TELL
        } else {
            FileCaps::TELL | FileCaps::SEEK
        };

        let whence = match whence {
            types::Whence::Cur => SeekFrom::Current(offset),
            types::Whence::End => SeekFrom::End(offset),
            types::Whence::Set => SeekFrom::Start(offset as u64),
        };
        let newoffset = self
            .table()
            .get_file_mut(u32::from(fd))?
            .get_cap_mut(required_caps)?
            .seek(whence)
            .await?;
        Ok(newoffset)
    }

    async fn fd_sync(&mut self, fd: types::Fd) -> Result<(), Error> {
        self.table()
            .get_file_mut(u32::from(fd))?
            .get_cap_mut(FileCaps::SYNC)?
            .sync()
            .await?;
        Ok(())
    }

    async fn fd_tell(&mut self, fd: types::Fd) -> Result<types::Filesize, Error> {
        // XXX should this be stream_position?
        let offset = self
            .table()
            .get_file_mut(u32::from(fd))?
            .get_cap_mut(FileCaps::TELL)?
            .seek(std::io::SeekFrom::Current(0))
            .await?;
        Ok(offset)
    }

    async fn fd_readdir<'a>(
        &mut self,
        fd: types::Fd,
        buf: &GuestPtr<'a, u8>,
        buf_len: types::Size,
        cookie: types::Dircookie,
    ) -> Result<types::Size, Error> {
        let mut bufused = 0;
        let mut buf = buf.clone();
        for entity in self
            .table()
            .get_dir(u32::from(fd))?
            .get_cap(DirCaps::READDIR)?
            .readdir(ReaddirCursor::from(cookie))
            .await?
        {
            let entity = entity?;
            let dirent_raw = dirent_bytes(types::Dirent::try_from(&entity)?);
            let dirent_len: types::Size = dirent_raw.len().try_into()?;
            let name_raw = entity.name.as_bytes();
            let name_len: types::Size = name_raw.len().try_into()?;

            // Copy as many bytes of the dirent as we can, up to the end of the buffer
            let dirent_copy_len = std::cmp::min(dirent_len, buf_len - bufused);
            buf.as_array(dirent_copy_len)
                .copy_from_slice(&dirent_raw[..dirent_copy_len as usize])?;

            // If the dirent struct wasnt compied entirely, return that we filled the buffer, which
            // tells libc that we're not at EOF.
            if dirent_copy_len < dirent_len {
                return Ok(buf_len);
            }

            buf = buf.add(dirent_copy_len)?;
            bufused += dirent_copy_len;

            // Copy as many bytes of the name as we can, up to the end of the buffer
            let name_copy_len = std::cmp::min(name_len, buf_len - bufused);
            buf.as_array(name_copy_len)
                .copy_from_slice(&name_raw[..name_copy_len as usize])?;

            // If the dirent struct wasn't copied entirely, return that we filled the buffer, which
            // tells libc that we're not at EOF

            if name_copy_len < name_len {
                return Ok(buf_len);
            }

            buf = buf.add(name_copy_len)?;
            bufused += name_copy_len;
        }
        Ok(bufused)
    }

    async fn path_create_directory<'a>(
        &mut self,
        dirfd: types::Fd,
        path: &GuestPtr<'a, str>,
    ) -> Result<(), Error> {
        self.table()
            .get_dir(u32::from(dirfd))?
            .get_cap(DirCaps::CREATE_DIRECTORY)?
            .create_dir(path.as_str()?.expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)").deref())
            .await
    }

    async fn path_filestat_get<'a>(
        &mut self,
        dirfd: types::Fd,
        flags: types::Lookupflags,
        path: &GuestPtr<'a, str>,
    ) -> Result<types::Filestat, Error> {
        let filestat = self
            .table()
            .get_dir(u32::from(dirfd))?
            .get_cap(DirCaps::PATH_FILESTAT_GET)?
            .get_path_filestat(
                path.as_str()?.expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)").deref(),
                flags.contains(types::Lookupflags::SYMLINK_FOLLOW),
            )
            .await?;
        Ok(types::Filestat::from(filestat))
    }

    async fn path_filestat_set_times<'a>(
        &mut self,
        dirfd: types::Fd,
        flags: types::Lookupflags,
        path: &GuestPtr<'a, str>,
        atim: types::Timestamp,
        mtim: types::Timestamp,
        fst_flags: types::Fstflags,
    ) -> Result<(), Error> {
        let set_atim = fst_flags.contains(types::Fstflags::ATIM);
        let set_atim_now = fst_flags.contains(types::Fstflags::ATIM_NOW);
        let set_mtim = fst_flags.contains(types::Fstflags::MTIM);
        let set_mtim_now = fst_flags.contains(types::Fstflags::MTIM_NOW);

        let atim = systimespec(set_atim, atim, set_atim_now).map_err(|e| e.context("atim"))?;
        let mtim = systimespec(set_mtim, mtim, set_mtim_now).map_err(|e| e.context("mtim"))?;
        self.table()
            .get_dir(u32::from(dirfd))?
            .get_cap(DirCaps::PATH_FILESTAT_SET_TIMES)?
            .set_times(
                path.as_str()?.expect("cannot use with shared memories; see https://github.com/bytecodealliance/wasmtime/issues/5235 (TODO)").deref(),
                atim,
                mtim,
                flags.contains(types::Lookupflags::SYMLINK_FOLLOW),
            )
            .await
    }

Implementors§