let write_byte_helper takes in io::Result<usize> as it will always take in Ok()

Author: tiif

src/shims/unix/fd.rs

@@ -164,7 +164,7 @@ impl FileDescription for io::Stdout {
         ecx: &mut MiriInterpCx<'tcx>,
     ) -> InterpResult<'tcx> {
         // We allow writing to stderr even with isolation enabled.
-        let result = Ok(Write::write(&mut { self }, bytes));
+        let result = Write::write(&mut { self }, bytes);
         // Stdout is buffered, flush to make sure it appears on the
         // screen.  This is the write() syscall of the interpreted
         // program, we want it to correspond to a write() syscall on
@@ -195,7 +195,7 @@ impl FileDescription for io::Stderr {
     ) -> InterpResult<'tcx> {
         // We allow writing to stderr even with isolation enabled.
         // No need to flush, stderr is not buffered.
-        let result = Ok(Write::write(&mut { self }, bytes));
+        let result = Write::write(&mut { self }, bytes);
         ecx.write_byte_helper(result, dest)?;
         Ok(())
     }
@@ -223,7 +223,7 @@ impl FileDescription for NullOutput {
         ecx: &mut MiriInterpCx<'tcx>,
     ) -> InterpResult<'tcx> {
         // We just don't write anything, but report to the user that we did.
-        let result = Ok(Ok(bytes.len()));
+        let result = Ok(bytes.len());
         ecx.write_byte_helper(result, dest)?;
         Ok(())
     }
@@ -682,11 +682,11 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
     fn write_byte_helper(
         &mut self,
-        result: InterpResult<'tcx, io::Result<usize>>,
+        result: io::Result<usize>,
         dest: &MPlaceTy<'tcx>,
     ) -> InterpResult<'tcx> {
         let this = self.eval_context_mut();
-        let result = this.try_unwrap_io_result(result?.map(|c| i64::try_from(c).unwrap()))?;
+        let result = this.try_unwrap_io_result(result.map(|c| i64::try_from(c).unwrap()))?;
         this.write_int(result, dest)?;
         Ok(())
     }

src/shims/unix/fs.rs

@@ -54,7 +54,7 @@ impl FileDescription for FileHandle {
         ecx: &mut MiriInterpCx<'tcx>,
     ) -> InterpResult<'tcx> {
         assert!(communicate_allowed, "isolation should have prevented even opening a file");
-        let result = Ok((&mut &self.file).write(bytes));
+        let result = (&mut &self.file).write(bytes);
         ecx.write_byte_helper(result, dest)?;
         Ok(())
     }
@@ -109,7 +109,7 @@ impl FileDescription for FileHandle {
                 .expect("failed to restore file position, this shouldn't be possible");
             res
         };
-        let result = Ok(f());
+        let result = f();
         ecx.write_byte_helper(result, dest)?;
         Ok(())
     }

src/shims/unix/linux/eventfd.rs

@@ -125,7 +125,7 @@ impl FileDescription for Event {
     ) -> InterpResult<'tcx> {
         // Check the size of slice, and return error only if the size of the slice < 8.
         let Some(bytes) = bytes.first_chunk::<U64_ARRAY_SIZE>() else {
-            let result = Ok(Err(Error::from(ErrorKind::InvalidInput)));
+            let result = Err(Error::from(ErrorKind::InvalidInput));
             ecx.write_byte_helper(result, dest)?;
             return Ok(());
         };
@@ -136,7 +136,7 @@ impl FileDescription for Event {
         };
         // u64::MAX as input is invalid because the maximum value of counter is u64::MAX - 1.
         if num == u64::MAX {
-            let result = Ok(Err(Error::from(ErrorKind::InvalidInput)));
+            let result = Err(Error::from(ErrorKind::InvalidInput));
             ecx.write_byte_helper(result, dest)?;
             return Ok(());
         }
@@ -152,7 +152,7 @@ impl FileDescription for Event {
             }
             None | Some(u64::MAX) => {
                 if self.is_nonblock {
-                    let result = Ok(Err(Error::from(ErrorKind::WouldBlock)));
+                    let result = Err(Error::from(ErrorKind::WouldBlock));
                     ecx.write_byte_helper(result, dest)?;
                     return Ok(());
                 } else {
@@ -165,7 +165,7 @@ impl FileDescription for Event {
         // types for current file description.
         ecx.check_and_update_readiness(self_ref)?;
 
-        let result = Ok(Ok(U64_ARRAY_SIZE));
+        let result = Ok(U64_ARRAY_SIZE);
         ecx.write_byte_helper(result, dest)?;
         Ok(())
     }

src/shims/unix/unnamed_socket.rs

@@ -211,7 +211,7 @@ impl FileDescription for AnonSocket {
         // Always succeed on write size 0.
         // ("If count is zero and fd refers to a file other than a regular file, the results are not specified.")
         if write_size == 0 {
-            let result = Ok(Ok(0));
+            let result = Ok(0);
             ecx.write_byte_helper(result, dest)?;
             return Ok(());
         }
@@ -220,7 +220,7 @@ impl FileDescription for AnonSocket {
         let Some(peer_fd) = self.peer_fd().upgrade() else {
             // If the upgrade from Weak to Rc fails, it indicates that all read ends have been
             // closed.
-            let result = Ok(Err(Error::from(ErrorKind::BrokenPipe)));
+            let result = Err(Error::from(ErrorKind::BrokenPipe));
             ecx.write_byte_helper(result, dest)?;
             return Ok(());
         };
@@ -236,7 +236,7 @@ impl FileDescription for AnonSocket {
         if available_space == 0 {
             if self.is_nonblock {
                 // Non-blocking socketpair with a full buffer.
-                let result = Ok(Err(Error::from(ErrorKind::WouldBlock)));
+                let result = Err(Error::from(ErrorKind::WouldBlock));
                 ecx.write_byte_helper(result, dest)?;
                 return Ok(());
             } else {
@@ -259,7 +259,7 @@ impl FileDescription for AnonSocket {
         // The kernel does this even if the fd was already readable before, so we follow suit.
         ecx.check_and_update_readiness(&peer_fd)?;
 
-        let result = Ok(Ok(actual_write_size));
+        let result = Ok(actual_write_size);
         ecx.write_byte_helper(result, dest)?;
         return Ok(());
     }