adapter: StreamType::Unknown is actually Stdio (#161)

We have only ever used Unknown for the stdio streams, and I don't expect
us to use it for anything else in the future, so rename it.

Set the returned filetype to character device: Closes #146.

Also, fix some warnings.

Author: pchickey

src/descriptors.rs

@@ -30,7 +30,7 @@ impl Drop for Descriptor {
                 match &stream.type_ {
                     StreamType::File(file) => filesystem::drop_descriptor(file.fd),
                     StreamType::Socket(_) => unreachable!(),
-                    StreamType::Unknown => {}
+                    StreamType::Stdio => {}
                 }
             }
             Descriptor::Closed(_) => {}
@@ -106,8 +106,8 @@ impl Streams {
 
 #[allow(dead_code)] // until Socket is implemented
 pub enum StreamType {
-    /// It's a valid stream but we don't know where it comes from.
-    Unknown,
+    /// Stream is used for implementing stdio.
+    Stdio,
 
     /// Streaming data with a file.
     File(File),
@@ -146,19 +146,19 @@ impl Descriptors {
         d.push(Descriptor::Streams(Streams {
             input: Cell::new(Some(stdio.stdin)),
             output: Cell::new(None),
-            type_: StreamType::Unknown,
+            type_: StreamType::Stdio,
         }))
         .trapping_unwrap();
         d.push(Descriptor::Streams(Streams {
             input: Cell::new(None),
             output: Cell::new(Some(stdio.stdout)),
-            type_: StreamType::Unknown,
+            type_: StreamType::Stdio,
         }))
         .trapping_unwrap();
         d.push(Descriptor::Streams(Streams {
             input: Cell::new(None),
             output: Cell::new(Some(stdio.stderr)),
-            type_: StreamType::Unknown,
+            type_: StreamType::Stdio,
         }))
         .trapping_unwrap();
 
@@ -324,16 +324,6 @@ impl Descriptors {
         }
     }
 
-    pub fn get_file_or_dir(&self, fd: Fd) -> Result<&File, Errno> {
-        match self.get(fd)? {
-            Descriptor::Streams(Streams {
-                type_: StreamType::File(file),
-                ..
-            }) => Ok(file),
-            _ => Err(wasi::ERRNO_BADF),
-        }
-    }
-
     pub fn get_file_with_error(&self, fd: Fd, error: Errno) -> Result<&File, Errno> {
         match self.get(fd)? {
             Descriptor::Streams(Streams {

src/lib.rs

@@ -498,9 +498,9 @@ pub unsafe extern "C" fn fd_fdstat_get(fd: Fd, stat: *mut Fdstat) -> Errno {
         | Descriptor::Streams(Streams {
             input,
             output,
-            type_: StreamType::Unknown,
+            type_: StreamType::Stdio,
         }) => {
-            let fs_filetype = FILETYPE_UNKNOWN;
+            let fs_filetype = FILETYPE_CHARACTER_DEVICE;
             let fs_flags = 0;
             let mut fs_rights_base = 0;
             if input.get().is_some() {
@@ -540,7 +540,7 @@ pub unsafe extern "C" fn fd_fdstat_set_flags(fd: Fd, flags: Fdflags) -> Errno {
             }) if !file.is_dir() => file,
             _ => Err(wasi::ERRNO_BADF)?,
         };
-        file.append = (flags & FDFLAGS_APPEND == FDFLAGS_APPEND);
+        file.append = flags & FDFLAGS_APPEND == FDFLAGS_APPEND;
         file.blocking = !(flags & FDFLAGS_NONBLOCK == FDFLAGS_NONBLOCK);
         Ok(())
     })
@@ -581,16 +581,15 @@ pub unsafe extern "C" fn fd_filestat_get(fd: Fd, buf: *mut Filestat) -> Errno {
                 };
                 Ok(())
             }
-            // For unknown (effectively, stdio) streams, instead of returning an error, return a
-            // Filestat with all zero fields and Filetype::Unknown.
+            // Stdio is all zero fields, except for filetype character device
             Descriptor::Streams(Streams {
-                type_: StreamType::Unknown,
+                type_: StreamType::Stdio,
                 ..
             }) => {
                 *buf = Filestat {
                     dev: 0,
                     ino: 0,
-                    filetype: FILETYPE_UNKNOWN,
+                    filetype: FILETYPE_CHARACTER_DEVICE,
                     nlink: 0,
                     size: 0,
                     atim: 0,
@@ -1749,7 +1748,7 @@ pub unsafe extern "C" fn poll_oneoff(
                                                }
                                                */
                             }
-                            StreamType::Unknown => {
+                            StreamType::Stdio => {
                                 error = ERRNO_SUCCESS;
                                 nbytes = 1;
                                 flags = 0;
@@ -1766,7 +1765,7 @@ pub unsafe extern "C" fn poll_oneoff(
                         .trapping_unwrap();
                     match desc {
                         Descriptor::Streams(streams) => match streams.type_ {
-                            StreamType::File(_) | StreamType::Unknown => {
+                            StreamType::File(_) | StreamType::Stdio => {
                                 error = ERRNO_SUCCESS;
                                 nbytes = 1;
                                 flags = 0;