The scope of the unsafe block can be appropriately reduced

native-windows-gui/examples/sync-draw/src/shared_memory.rs

@@ -128,8 +128,8 @@ impl SharedMemory {
     /// Fetch the next instance id in the shared memory.
     pub fn next_instance_id(&self) -> u32 {
         let header_ptr = SharedMemory::map_view(self.handle, 0, HEADER_SIZE) as *mut SharedHeader;
-        let next_id = unsafe {
-            let header = &mut *header_ptr;
+        let next_id = {
+            let header = unsafe { &mut *header_ptr };
             header.next_instance_id += 1;
             header.next_instance_id
         };
@@ -234,14 +234,14 @@ impl SharedMemory {
 
     /// Safe wrapper over MapViewOfFile
     fn map_view(handle: HANDLE, offset: DWORD, size: SIZE_T) -> *mut u8 {
-        unsafe {
-            let handle = MapViewOfFile(handle, FILE_MAP_ALL_ACCESS, 0, offset, size) as *mut u8;
+
+            let handle = unsafe { MapViewOfFile(handle, FILE_MAP_ALL_ACCESS, 0, offset, size) as *mut u8 };
             if handle.is_null() {
                 panic!("Could not map memory region");
             }
 
             handle
-        }
+
     }
 
     /// Safe wrapper over UnmapViewOfFile

native-windows-gui/src/events.rs

@@ -478,9 +478,9 @@ impl ToolTipTextData {
         }
 
         self.clear();
+        let data = unsafe { &mut *self.data };
+        let local_text = to_utf16(text);
         unsafe {
-            let data = &mut *self.data;
-            let local_text = to_utf16(text);
             ptr::copy_nonoverlapping(local_text.as_ptr(), data.szText.as_mut_ptr(), text_len);
         }
     }
@@ -539,11 +539,11 @@ impl PaintData {
 
     /// Wrapper over BeginPaint
     pub fn begin_paint(&self) -> PAINTSTRUCT {
-        unsafe {
-            let mut paint: PAINTSTRUCT = ::std::mem::zeroed();
-            BeginPaint(self.hwnd, &mut paint);
+
+            let mut paint: PAINTSTRUCT = unsafe { ::std::mem::zeroed() };
+            unsafe { BeginPaint(self.hwnd, &mut paint) };
             paint
-        }
+
     }
 
     /// Wrapper over EndPaint
@@ -568,11 +568,11 @@ impl DropFiles {
     pub fn point(&self) -> [i32; 2] {
         use winapi::um::shellapi::DragQueryPoint;
 
-        unsafe {
+
             let mut pt = POINT { x: 0, y: 0 };
-            DragQueryPoint(self.drop, &mut pt);
+            unsafe { DragQueryPoint(self.drop, &mut pt) };
             [pt.x, pt.y]
-        }
+
     }
 
     /// Return the number of files dropped 
@@ -593,19 +593,19 @@ impl DropFiles {
 
         let len = self.len();
         let mut files = Vec::with_capacity(len);
-        unsafe {
+
             for i in 0..len {
                 // Need to add a +1 here for some reason
-                let buffer_size = (DragQueryFileW(self.drop, i as _, ptr::null_mut(), 0) + 1) as usize;
+                let buffer_size = unsafe { (DragQueryFileW(self.drop, i as _, ptr::null_mut(), 0) + 1) as usize };
 
                 let mut buffer: Vec<u16> = Vec::with_capacity(buffer_size);
-                buffer.set_len(buffer_size);
+                unsafe { buffer.set_len(buffer_size) };
 
-                DragQueryFileW(self.drop, i as _, buffer.as_mut_ptr(), buffer_size as _);
+                unsafe { DragQueryFileW(self.drop, i as _, buffer.as_mut_ptr(), buffer_size as _) };
 
                 files.push(from_utf16(&buffer));
             }
-        }
+
 
         files
     }

native-windows-gui/src/win32/window_helper.rs

@@ -94,23 +94,23 @@ pub fn destroy_window(hwnd: HWND) {
 pub fn destroy_menu_item(parent: HMENU, item_id: u32) { 
     use winapi::um::winuser::{DeleteMenu, GetMenuItemCount, GetMenuItemID, MF_BYPOSITION};
 
-    unsafe {
-        let count = GetMenuItemCount(parent);
+
+        let count = unsafe { GetMenuItemCount(parent) };
         let mut index = 0;
 
         while index < count {
-            let id = GetMenuItemID(parent, index);
+            let id = unsafe { GetMenuItemID(parent, index) };
             match id == item_id {
                 true => {
-                    DeleteMenu(parent, index as u32, MF_BYPOSITION);
+                    unsafe { DeleteMenu(parent, index as u32, MF_BYPOSITION) };
                     index = count;
                 },
                 false => {
                     index += 1;
                 }
             }
         }
-    }
+
 }
 
 pub fn destroy_menu(menu: HMENU) {