Implement set_last_error_and_return_i64, bug fixes

Author: noahmbright

src/shims/io_error.rs

@@ -141,6 +141,16 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         interp_ok(Scalar::from_i32(-1))
     }
 
+    /// Sets the last OS error and return `-1` as a `i32`-typed Scalar
+    fn set_last_error_and_return_i64(
+        &mut self,
+        err: impl Into<IoError>,
+    ) -> InterpResult<'tcx, Scalar> {
+        let this = self.eval_context_mut();
+        this.set_last_error(err)?;
+        interp_ok(Scalar::from_i64(-1))
+    }
+
     /// Gets the last error variable.
     fn get_last_error(&mut self) -> InterpResult<'tcx, Scalar> {
         let this = self.eval_context_mut();

src/shims/unix/fd.rs

@@ -561,7 +561,8 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
     /// types (like `read`, that returns an `i64`).
     fn fd_not_found<T: From<i32>>(&mut self) -> InterpResult<'tcx, T> {
         let this = self.eval_context_mut();
-        return this.set_last_error_and_return_i32(LibcError("EBADF"));
+        this.set_last_error(LibcError("EBADF"))?;
+        Ok((-1).into())
     }
 
     /// Read data from `fd` into buffer specified by `buf` and `count`.

src/shims/unix/fs.rs

@@ -2,7 +2,7 @@
 
 use std::borrow::Cow;
 use std::fs::{
-    read_dir, remove_dir, remove_file, rename, DirBuilder, File, FileType, OpenOptions, ReadDir,
+    DirBuilder, File, FileType, OpenOptions, ReadDir, read_dir, remove_dir, remove_file, rename,
 };
 use std::io::{self, ErrorKind, IsTerminal, Read, Seek, SeekFrom, Write};
 use std::path::{Path, PathBuf};
@@ -203,7 +203,7 @@ impl FileDescription for FileHandle {
                 ERROR_IO_PENDING, ERROR_LOCK_VIOLATION, FALSE, HANDLE, TRUE,
             };
             use windows_sys::Win32::Storage::FileSystem::{
-                LockFileEx, UnlockFile, LOCKFILE_EXCLUSIVE_LOCK, LOCKFILE_FAIL_IMMEDIATELY,
+                LOCKFILE_EXCLUSIVE_LOCK, LOCKFILE_FAIL_IMMEDIATELY, LockFileEx, UnlockFile,
             };
 
             let fh = self.file.as_raw_handle() as HANDLE;
@@ -632,11 +632,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         #[cfg(windows)]
         fn create_link(src: &Path, dst: &Path) -> std::io::Result<()> {
             use std::os::windows::fs;
-            if src.is_dir() {
-                fs::symlink_dir(src, dst)
-            } else {
-                fs::symlink_file(src, dst)
-            }
+            if src.is_dir() { fs::symlink_dir(src, dst) } else { fs::symlink_file(src, dst) }
         }
 
         let this = self.eval_context_mut();
@@ -1227,13 +1223,17 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 this.write_null(&this.deref_pointer(result_op)?)?;
                 0
             }
-            Some(Err(e)) => match e.raw_os_error() {
-                // return positive error number on error
-                Some(error) => error,
-                None => {
-                    throw_unsup_format!("the error {} couldn't be converted to a return value", e)
-                }
-            },
+            Some(Err(e)) =>
+                match e.raw_os_error() {
+                    // return positive error number on error
+                    Some(error) => error,
+                    None => {
+                        throw_unsup_format!(
+                            "the error {} couldn't be converted to a return value",
+                            e
+                        )
+                    }
+                },
         }))
     }
 
@@ -1432,7 +1432,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
                 this.write_bytes_ptr(buf, path_bytes.iter().copied())?;
                 interp_ok(path_bytes.len().try_into().unwrap())
             }
-            Err(e) => Ok(this.set_last_error_and_return_i64(e)),
+            Err(e) => this.set_last_error_and_return_i64(e),
         }
     }
 

src/shims/unix/linux/epoll.rs

@@ -266,7 +266,7 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 
         // Throw EINVAL if epfd and fd have the same value.
         if epfd_value == fd {
-            this.set_last_error_and_return_i32(LibcError("EINVAL"))
+            return this.set_last_error_and_return_i32(LibcError("EINVAL"));
         }
 
         // Check if epfd is a valid epoll file descriptor.