chore: fix Windows specific clippy errors (#15212)

cli/deno_dir.rs

@@ -133,6 +133,7 @@ mod dirs {
   use winapi::um::{combaseapi, knownfolders, shlobj, shtypes, winbase, winnt};
 
   fn known_folder(folder_id: shtypes::REFKNOWNFOLDERID) -> Option<PathBuf> {
+    // SAFETY: winapi calls
     unsafe {
       let mut path_ptr: winnt::PWSTR = std::ptr::null_mut();
       let result = shlobj::SHGetKnownFolderPath(

cli/lsp/parent_process_checker.rs

@@ -39,6 +39,7 @@ fn is_process_active(process_id: u32) -> bool {
   use winapi::um::synchapi::WaitForSingleObject;
   use winapi::um::winnt::SYNCHRONIZE;
 
+  // SAFETY: winapi calls
   unsafe {
     let process = OpenProcess(SYNCHRONIZE, FALSE, process_id as DWORD);
     let result = if process == NULL {

cli/windows_util.rs

@@ -5,6 +5,7 @@
 /// constructed from a stdio handle; if the handle is null this causes a panic.
 pub fn ensure_stdio_open() {
   #[cfg(windows)]
+  // SAFETY: winapi calls
   unsafe {
     use std::mem::size_of;
     use winapi::shared::minwindef::DWORD;

ext/ffi/build.rs

@@ -1,8 +1,9 @@
 // Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
 
-use std::env;
-
+#[cfg(not(target_os = "windows"))]
 fn build_tcc() {
+  use std::env;
+
   {
     // TODO(@littledivy): Windows support for fast call.
     // let tcc_path = root
@@ -58,6 +59,8 @@ fn main() {}
 
 #[cfg(not(target_os = "windows"))]
 fn main() {
+  use std::env;
+
   if let Ok(tcc_path) = env::var("TCC_PATH") {
     println!("cargo:rustc-link-search=native={}", tcc_path);
   } else {

ext/ffi/lib.rs

@@ -518,8 +518,10 @@ pub(crate) fn format_error(e: dlopen::Error, path: String) -> String {
       let arguments = [path.as_ptr()];
 
       loop {
-        unsafe {
-          let length = FormatMessageW(
+        // SAFETY:
+        // winapi call to format the error message
+        let length = unsafe {
+          FormatMessageW(
             FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_ARGUMENT_ARRAY,
             std::ptr::null_mut(),
             err_num as DWORD,
@@ -527,22 +529,24 @@ pub(crate) fn format_error(e: dlopen::Error, path: String) -> String {
             buf.as_mut_ptr(),
             buf.len() as DWORD,
             arguments.as_ptr() as _,
-          );
+          )
+        };
 
-          if length == 0 {
-            let err_num = GetLastError();
-            if err_num == ERROR_INSUFFICIENT_BUFFER {
-              buf.resize(buf.len() * 2, 0);
-              continue;
-            }
-
-            // Something went wrong, just return the original error.
-            return e.to_string();
+        if length == 0 {
+          // SAFETY:
+          // winapi call to get the last error message
+          let err_num = unsafe { GetLastError() };
+          if err_num == ERROR_INSUFFICIENT_BUFFER {
+            buf.resize(buf.len() * 2, 0);
+            continue;
           }
 
-          let msg = String::from_utf16_lossy(&buf[..length as usize]);
-          return msg;
+          // Something went wrong, just return the original error.
+          return e.to_string();
         }
+
+        let msg = String::from_utf16_lossy(&buf[..length as usize]);
+        return msg;
       }
     }
     _ => e.to_string(),

runtime/ops/process.rs

@@ -318,21 +318,26 @@ pub fn kill(pid: i32, signal: &str) -> Result<(), AnyError> {
   } else if pid <= 0 {
     Err(type_error("Invalid pid"))
   } else {
+    // SAFETY: winapi call
     let handle = unsafe { OpenProcess(PROCESS_TERMINATE, FALSE, pid as DWORD) };
 
     if handle.is_null() {
+      // SAFETY: winapi call
       let err = match unsafe { GetLastError() } {
         ERROR_INVALID_PARAMETER => Error::from(NotFound), // Invalid `pid`.
         errno => Error::from_raw_os_error(errno as i32),
       };
       Err(err.into())
     } else {
-      let is_terminated = unsafe { TerminateProcess(handle, 1) };
-      unsafe { CloseHandle(handle) };
-      match is_terminated {
-        FALSE => Err(Error::last_os_error().into()),
-        TRUE => Ok(()),
-        _ => unreachable!(),
+      // SAFETY: winapi calls
+      unsafe {
+        let is_terminated = TerminateProcess(handle, 1);
+        CloseHandle(handle);
+        match is_terminated {
+          FALSE => Err(Error::last_os_error().into()),
+          TRUE => Ok(()),
+          _ => unreachable!(),
+        }
       }
     }
   }

runtime/ops/runtime.rs

@@ -51,6 +51,7 @@ pub fn ppid() -> i64 {
       CreateToolhelp32Snapshot, Process32First, Process32Next, PROCESSENTRY32,
       TH32CS_SNAPPROCESS,
     };
+    // SAFETY: winapi calls
     unsafe {
       // Take a snapshot of system processes, one of which is ours
       // and contains our parent's pid

runtime/ops/tty.rs

@@ -95,6 +95,7 @@ fn op_set_raw(state: &mut OpState, args: SetRawArgs) -> Result<(), AnyError> {
         return Err(custom_error("ReferenceError", "null handle"));
       }
       let mut original_mode: DWORD = 0;
+      // SAFETY: winapi call
       if unsafe { consoleapi::GetConsoleMode(handle, &mut original_mode) }
         == FALSE
       {
@@ -105,6 +106,7 @@ fn op_set_raw(state: &mut OpState, args: SetRawArgs) -> Result<(), AnyError> {
       } else {
         original_mode | RAW_MODE_MASK
       };
+      // SAFETY: winapi call
       if unsafe { consoleapi::SetConsoleMode(handle, new_mode) } == FALSE {
         return Err(Error::last_os_error().into());
       }
@@ -210,6 +212,7 @@ fn op_console_size(
       use std::os::windows::io::AsRawHandle;
       let handle = std_file.as_raw_handle();
 
+      // SAFETY: winapi calls
       unsafe {
         let mut bufinfo: winapi::um::wincon::CONSOLE_SCREEN_BUFFER_INFO =
           std::mem::zeroed();

runtime/permissions.rs

@@ -1912,6 +1912,7 @@ fn permission_prompt(message: &str, name: &str) -> bool {
     use winapi::um::winuser::MAPVK_VK_TO_VSC;
     use winapi::um::winuser::VK_RETURN;
 
+    // SAFETY: winapi calls
     unsafe {
       let stdin = GetStdHandle(STD_INPUT_HANDLE);
       // emulate an enter key press to clear any line buffered console characters

test_util/src/pty.rs

@@ -153,6 +153,8 @@ mod windows {
       maybe_env_vars: Option<HashMap<String, String>>,
     ) -> Self {
       // https://docs.microsoft.com/en-us/windows/console/creating-a-pseudoconsole-session
+      // SAFETY:
+      // Generous use of winapi to create a PTY (thus large unsafe block).
       unsafe {
         let mut size: COORD = std::mem::zeroed();
         size.X = 800;
@@ -238,22 +240,24 @@ mod windows {
 
   impl Read for WinPseudoConsole {
     fn read(&mut self, buf: &mut [u8]) -> std::io::Result<usize> {
-      unsafe {
-        loop {
-          let mut bytes_read = 0;
-          let success = ReadFile(
+      loop {
+        let mut bytes_read = 0;
+        // SAFETY:
+        // winapi call
+        let success = unsafe {
+          ReadFile(
             self.stdout_read_handle.as_raw_handle(),
             buf.as_mut_ptr() as _,
             buf.len() as u32,
             &mut bytes_read,
             ptr::null_mut(),
-          );
+          )
+        };
 
-          // ignore zero-byte writes
-          let is_zero_byte_write = bytes_read == 0 && success == TRUE;
-          if !is_zero_byte_write {
-            return Ok(bytes_read as usize);
-          }
+        // ignore zero-byte writes
+        let is_zero_byte_write = bytes_read == 0 && success == TRUE;
+        if !is_zero_byte_write {
+          return Ok(bytes_read as usize);
         }
       }
     }
@@ -271,17 +275,19 @@ mod windows {
 
   impl std::io::Write for WinPseudoConsole {
     fn write(&mut self, buffer: &[u8]) -> std::io::Result<usize> {
-      unsafe {
-        let mut bytes_written = 0;
-        assert_win_success!(WriteFile(
+      let mut bytes_written = 0;
+      // SAFETY:
+      // winapi call
+      assert_win_success!(unsafe {
+        WriteFile(
           self.stdin_write_handle.as_raw_handle(),
           buffer.as_ptr() as *const _,
           buffer.len() as u32,
           &mut bytes_written,
           ptr::null_mut(),
-        ));
-        Ok(bytes_written as usize)
-      }
+        )
+      });
+      Ok(bytes_written as usize)
     }
 
     fn flush(&mut self) -> std::io::Result<()> {
@@ -299,10 +305,14 @@ mod windows {
     }
 
     pub fn duplicate(&self) -> WinHandle {
-      unsafe {
-        let process_handle = GetCurrentProcess();
-        let mut duplicate_handle = ptr::null_mut();
-        assert_win_success!(DuplicateHandle(
+      // SAFETY:
+      // winapi call
+      let process_handle = unsafe { GetCurrentProcess() };
+      let mut duplicate_handle = ptr::null_mut();
+      // SAFETY:
+      // winapi call
+      assert_win_success!(unsafe {
+        DuplicateHandle(
           process_handle,
           self.inner,
           process_handle,
@@ -310,10 +320,10 @@ mod windows {
           0,
           0,
           DUPLICATE_SAME_ACCESS,
-        ));
+        )
+      });
 
-        WinHandle::new(duplicate_handle)
-      }
+      WinHandle::new(duplicate_handle)
     }
 
     pub fn as_raw_handle(&self) -> HANDLE {
@@ -333,8 +343,10 @@ mod windows {
 
   impl Drop for WinHandle {
     fn drop(&mut self) {
-      unsafe {
-        if !self.inner.is_null() && self.inner != INVALID_HANDLE_VALUE {
+      if !self.inner.is_null() && self.inner != INVALID_HANDLE_VALUE {
+        // SAFETY:
+        // winapi call
+        unsafe {
           winapi::um::handleapi::CloseHandle(self.inner);
         }
       }
@@ -347,6 +359,8 @@ mod windows {
 
   impl ProcThreadAttributeList {
     pub fn new(console_handle: HPCON) -> Self {
+      // SAFETY:
+      // Generous use of unsafe winapi calls to create a ProcThreadAttributeList.
       unsafe {
         // discover size required for the list
         let mut size = 0;
@@ -393,24 +407,23 @@ mod windows {
 
   impl Drop for ProcThreadAttributeList {
     fn drop(&mut self) {
+      // SAFETY:
+      // winapi call
       unsafe { DeleteProcThreadAttributeList(self.as_mut_ptr()) };
     }
   }
 
   fn create_pipe() -> (WinHandle, WinHandle) {
-    unsafe {
-      let mut read_handle = std::ptr::null_mut();
-      let mut write_handle = std::ptr::null_mut();
+    let mut read_handle = std::ptr::null_mut();
+    let mut write_handle = std::ptr::null_mut();
 
-      assert_win_success!(CreatePipe(
-        &mut read_handle,
-        &mut write_handle,
-        ptr::null_mut(),
-        0
-      ));
+    // SAFETY:
+    // Creating an anonymous pipe with winapi.
+    assert_win_success!(unsafe {
+      CreatePipe(&mut read_handle, &mut write_handle, ptr::null_mut(), 0)
+    });
 
-      (WinHandle::new(read_handle), WinHandle::new(write_handle))
-    }
+    (WinHandle::new(read_handle), WinHandle::new(write_handle))
   }
 
   fn to_windows_str(str: &str) -> Vec<u16> {