Add a typesafe enum for file type

src/hostcalls_impl/fs.rs

@@ -1062,3 +1062,23 @@ pub(crate) unsafe fn fd_prestat_dir_name(
             enc_slice_of(memory, path.as_bytes(), path_ptr)
         })
 }
+
+#[allow(dead_code)] // trouble with sockets
+#[derive(Clone, Copy, Debug)]
+#[repr(u8)]
+pub(crate) enum FileType {
+    Unknown = host::__WASI_FILETYPE_UNKNOWN,
+    BlockDevice = host::__WASI_FILETYPE_BLOCK_DEVICE,
+    CharacterDevice = host::__WASI_FILETYPE_CHARACTER_DEVICE,
+    Directory = host::__WASI_FILETYPE_DIRECTORY,
+    RegularFile = host::__WASI_FILETYPE_REGULAR_FILE,
+    SocketDgram = host::__WASI_FILETYPE_SOCKET_DGRAM,
+    SocketStream = host::__WASI_FILETYPE_SOCKET_STREAM,
+    Symlink = host::__WASI_FILETYPE_SYMBOLIC_LINK,
+}
+
+impl FileType {
+    pub(crate) fn to_wasi(&self) -> host::__wasi_filetype_t {
+        *self as host::__wasi_filetype_t
+    }
+}

src/sys/unix/host_impl.rs

@@ -2,6 +2,7 @@
 #![allow(non_camel_case_types)]
 #![allow(non_snake_case)]
 #![allow(dead_code)]
+use crate::hostcalls_impl::FileType;
 use crate::{host, memory, Error, Result};
 use log::warn;
 use std::ffi::OsStr;
@@ -156,22 +157,22 @@ pub(crate) fn nix_from_oflags(oflags: host::__wasi_oflags_t) -> nix::fcntl::OFla
     nix_flags
 }
 
-pub(crate) fn filetype_from_nix(sflags: nix::sys::stat::SFlag) -> host::__wasi_filetype_t {
+pub(crate) fn filetype_from_nix(sflags: nix::sys::stat::SFlag) -> FileType {
     use nix::sys::stat::SFlag;
     if sflags.contains(SFlag::S_IFCHR) {
-        host::__WASI_FILETYPE_CHARACTER_DEVICE
+        FileType::CharacterDevice
     } else if sflags.contains(SFlag::S_IFBLK) {
-        host::__WASI_FILETYPE_BLOCK_DEVICE
+        FileType::BlockDevice
     } else if sflags.contains(SFlag::S_IFSOCK) {
-        host::__WASI_FILETYPE_SOCKET_STREAM
+        FileType::SocketStream
     } else if sflags.contains(SFlag::S_IFDIR) {
-        host::__WASI_FILETYPE_DIRECTORY
+        FileType::Directory
     } else if sflags.contains(SFlag::S_IFREG) {
-        host::__WASI_FILETYPE_REGULAR_FILE
+        FileType::RegularFile
     } else if sflags.contains(SFlag::S_IFLNK) {
-        host::__WASI_FILETYPE_SYMBOLIC_LINK
+        FileType::Symlink
     } else {
-        host::__WASI_FILETYPE_UNKNOWN
+        FileType::Unknown
     }
 }
 
@@ -200,7 +201,7 @@ pub(crate) fn filestat_from_nix(
         st_atim,
         st_ctim,
         st_mtim,
-        st_filetype: filetype_from_nix(filetype),
+        st_filetype: filetype_from_nix(filetype).to_wasi(),
     })
 }
 

src/sys/unix/hostcalls_impl/fs.rs

@@ -2,7 +2,7 @@
 #![allow(unused_unsafe)]
 use super::fs_helpers::*;
 use crate::helpers::systemtime_to_timestamp;
-use crate::hostcalls_impl::PathGet;
+use crate::hostcalls_impl::{FileType, PathGet};
 use crate::sys::host_impl;
 use crate::{host, Error, Result};
 use nix::libc;
@@ -219,35 +219,35 @@ pub(crate) fn fd_filestat_get_impl(file: &std::fs::File) -> Result<host::__wasi_
         st_atim: systemtime_to_timestamp(metadata.accessed()?)?,
         st_ctim: metadata.ctime().try_into()?, // i64 doesn't fit into u64
         st_mtim: systemtime_to_timestamp(metadata.modified()?)?,
-        st_filetype: filetype(file, &metadata)?,
+        st_filetype: filetype(file, &metadata)?.to_wasi(),
     })
 }
 
-fn filetype(file: &File, metadata: &Metadata) -> Result<host::__wasi_filetype_t> {
+fn filetype(file: &File, metadata: &Metadata) -> Result<FileType> {
     use nix::sys::socket::{self, SockType};
     use std::os::unix::fs::FileTypeExt;
     let ftype = metadata.file_type();
     if ftype.is_file() {
-        Ok(host::__WASI_FILETYPE_REGULAR_FILE)
+        Ok(FileType::RegularFile)
     } else if ftype.is_dir() {
-        Ok(host::__WASI_FILETYPE_DIRECTORY)
+        Ok(FileType::Directory)
     } else if ftype.is_symlink() {
-        Ok(host::__WASI_FILETYPE_SYMBOLIC_LINK)
+        Ok(FileType::Symlink)
     } else if ftype.is_char_device() {
-        Ok(host::__WASI_FILETYPE_CHARACTER_DEVICE)
+        Ok(FileType::CharacterDevice)
     } else if ftype.is_block_device() {
-        Ok(host::__WASI_FILETYPE_BLOCK_DEVICE)
+        Ok(FileType::BlockDevice)
     } else if ftype.is_socket() {
         match socket::getsockopt(file.as_raw_fd(), socket::sockopt::SockType)
             .map_err(|err| err.as_errno().unwrap())
             .map_err(host_impl::errno_from_nix)?
         {
-            SockType::Datagram => Ok(host::__WASI_FILETYPE_SOCKET_DGRAM),
+            SockType::Datagram => Ok(FileType::SocketDgram),
-            SockType::Stream => Ok(host::__WASI_FILETYPE_SOCKET_STREAM),
+            SockType::Stream => Ok(FileType::SocketStream),
-            _ => Ok(host::__WASI_FILETYPE_UNKNOWN),
+            _ => Ok(FileType::Unknown),
         }
     } else {
-        Ok(host::__WASI_FILETYPE_UNKNOWN)
+        Ok(FileType::Unknown)
     }
 }
 

src/sys/windows/hostcalls_impl/fs.rs

@@ -4,7 +4,7 @@ use super::fs_helpers::*;
 use crate::ctx::WasiCtx;
 use crate::fdentry::FdEntry;
 use crate::helpers::systemtime_to_timestamp;
-use crate::hostcalls_impl::{fd_filestat_set_times_impl, PathGet};
+use crate::hostcalls_impl::{fd_filestat_set_times_impl, FileType, PathGet};
 use crate::sys::fdentry_impl::{determine_type_rights, OsFile};
 use crate::sys::host_impl;
 use crate::sys::hostcalls_impl::fs_helpers::PathGetExt;
@@ -286,20 +286,20 @@ pub(crate) fn fd_filestat_get_impl(file: &std::fs::File) -> Result<host::__wasi_
         st_atim: systemtime_to_timestamp(metadata.accessed()?)?,
         st_ctim: change_time(file, &metadata)?.try_into()?, // i64 doesn't fit into u64
         st_mtim: systemtime_to_timestamp(metadata.modified()?)?,
-        st_filetype: filetype(file, &metadata)?,
+        st_filetype: filetype(file, &metadata)?.to_wasi(),
     })
 }
 
-fn filetype(_file: &File, metadata: &Metadata) -> Result<host::__wasi_filetype_t> {
+fn filetype(_file: &File, metadata: &Metadata) -> Result<FileType> {
     let ftype = metadata.file_type();
     let ret = if ftype.is_file() {
-        host::__WASI_FILETYPE_REGULAR_FILE
+        FileType::RegularFile
     } else if ftype.is_dir() {
-        host::__WASI_FILETYPE_DIRECTORY
+        FileType::Directory
     } else if ftype.is_symlink() {
-        host::__WASI_FILETYPE_SYMBOLIC_LINK
+        FileType::Symlink
     } else {
-        host::__WASI_FILETYPE_UNKNOWN
+        FileType::Unknown
     };
 
     Ok(ret)