Implemented bounds checking for update_with_buffer

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "minifb"
-version = "0.9.2"
+version = "0.10.0"
 license = "MIT/Apache-2.0"
 authors = ["Daniel Collin <daniel@collin.com>"]
 description = "Cross-platform window setup with optional bitmap rendering"

README.md

@@ -43,7 +43,8 @@ fn main() {
             *i = 0; // write something more funny here!
         }
 
-        window.update_with_buffer(&buffer);
+        // We unwrap here as we want this code to exit if it fails. Real applications may want to handle this in a different way
+        window.update_with_buffer(&buffer).unwrap();
     }
 }
 ```

examples/menu.rs

@@ -26,7 +26,7 @@ fn main() {
 
     let mut window = Window::new("Menu Test - Press ESC to exit",
                                  WIDTH,
-                                 HEIGHT,
+                                 HEIGHT + 2,
                                  WindowOptions {
                                      resize: true,
                                      scale: Scale::X2,
@@ -98,6 +98,7 @@ fn main() {
             }
         });
 
-        window.update_with_buffer(&buffer);
+        // We unwrap here as we want this code to exit if it fails
+        window.update_with_buffer(&buffer).unwrap();
     }
 }

examples/mouse.rs

@@ -38,6 +38,7 @@ fn main() {
             println!("Scrolling {} - {}", scroll.0, scroll.1);
         });
 
-        window.update_with_buffer(&buffer);
+        // We unwrap here as we want this code to exit if it fails
+        window.update_with_buffer(&buffer).unwrap();
     }
 }

examples/noise.rs

@@ -48,6 +48,7 @@ fn main() {
             }
         });
 
-        window.update_with_buffer(&buffer);
+        // We unwrap here as we want this code to exit if it fails
+        window.update_with_buffer(&buffer).unwrap();
     }
 }

examples/title_cursor.rs

@@ -73,7 +73,8 @@ fn main() {
             }
         }
 
-        window.update_with_buffer(&buffer);
+        // We unwrap here as we want this code to exit if it fails
+        window.update_with_buffer(&buffer).unwrap();
     }
 }
 

src/buffer_helper.rs

@@ -0,0 +1,15 @@
+use error::Error;
+use Result;
+
+pub fn check_buffer_size(window_width: usize, window_height: usize, scale: usize, buffer: &[u32]) -> Result<()> {
+    let buffer_size = buffer.len() * 4; // len is the number of entries so * 4 as we want bytes
+    let required_buffer_size = (window_width / scale) * (window_height / scale) * 4;    // * 4 for 32-bit buffer
+
+    if buffer_size < required_buffer_size {
+        let err = format!("Update failed because input buffer is too small. Required size for {} x {} window ({}x scale) is {} bytes but the size of the input buffer has the size {} bytes",
+                           window_width, window_height, scale, required_buffer_size, buffer_size);
+        Err(Error::UpdateFailed(err))
+    } else {
+        Ok(())
+    }
+}

src/error.rs

@@ -5,12 +5,14 @@ use std::fmt;
 ///
 #[derive(Debug)]
 pub enum Error {
-    /// Returned if menu Menu function isn't supported 
+    /// Returned if menu Menu function isn't supported
     MenusNotSupported,
-    /// Menu already exists 
+    /// Menu already exists
     MenuExists(String),
-    /// Menu already exists 
+    /// Menu already exists
     WindowCreate(String),
+    /// Unable to Update
+    UpdateFailed(String),
 }
 
 impl StdError for Error {
@@ -18,7 +20,8 @@ impl StdError for Error {
         match *self {
             Error::MenusNotSupported => "Menus not supported",
             Error::MenuExists(_) => "Menu already exists",
-            Error::WindowCreate(_) => "Failed to create Window",
+            Error::WindowCreate(_) => "Failed to create window",
+            Error::UpdateFailed(_) => "Failed to Update",
         }
     }
 
@@ -27,6 +30,7 @@ impl StdError for Error {
             Error::MenusNotSupported => None,
             Error::MenuExists(_) => None,
             Error::WindowCreate(_) => None,
+            Error::UpdateFailed(_) => None,
         }
     }
 }
@@ -43,6 +47,9 @@ impl fmt::Display for Error {
             Error::WindowCreate(ref e) => {
                 write!(fmt, "{} {:?}", self.description(), e)
             }
+            Error::UpdateFailed(ref e) => {
+                write!(fmt, "{} {:?}", self.description(), e)
+            }
         }
     }
 }

src/lib.rs

@@ -100,6 +100,7 @@ pub use key::Key as Key;
 #[doc(hidden)]
 pub mod os;
 mod mouse_handler;
+mod buffer_helper;
 mod key_handler;
 mod window_flags;
 //mod menu;
@@ -222,10 +223,10 @@ impl Window {
     ///
     /// let mut window = match Window::new("Test", 640, 400, WindowOptions::default()).unwrap();
     ///
-    /// window.update_with_buffer(&buffer);
+    /// window.update_with_buffer(&buffer).unwrap();
     /// ```
     #[inline]
-    pub fn update_with_buffer(&mut self, buffer: &[u32]) {
+    pub fn update_with_buffer(&mut self, buffer: &[u32]) -> Result<()> {
         self.0.update_with_buffer(buffer)
     }
 

src/os/macos/mod.rs

@@ -7,6 +7,7 @@ use Result;
 // use MenuItem;
 use InputCallback;
 use mouse_handler;
+use buffer_helper;
 use window_flags;
 use {CursorStyle, MenuItem, MenuItemHandle, MenuHandle};
 // use menu::Menu;
@@ -291,9 +292,17 @@ impl Window {
         mfb_set_mouse_data(self.window_handle, &mut self.shared_data);
     }
 
-    pub fn update_with_buffer(&mut self, buffer: &[u32]) {
+    pub fn update_with_buffer(&mut self, buffer: &[u32]) -> Result<()> {
         self.key_handler.update();
 
+        let check_res = buffer_helper::check_buffer_size(self.shared_data.width as usize,
+                                                         self.shared_data.height as usize,
+                                                         self.scale_factor as usize,
+                                                         buffer);
+        if check_res.is_err() {
+            return check_res;
+        }
+
         unsafe {
             mfb_update_with_buffer(self.window_handle, buffer.as_ptr() as *const u8);
             Self::set_mouse_data(self);
@@ -302,6 +311,8 @@ impl Window {
                                  key_callback,
                                  char_callback);
         }
+
+        Ok(())
     }
 
     pub fn update(&mut self) {

src/os/redox/mod.rs

@@ -6,6 +6,7 @@ use os::redox::orbclient::Renderer;
 use error::Error;
 use Result;
 use mouse_handler;
+use buffer_height;
 use key_handler::KeyHandler;
 use InputCallback;
 use {CursorStyle, MouseButton, MouseMode};
@@ -100,11 +101,19 @@ impl Window {
         0 as *mut raw::c_void
     }
 
-    pub fn update_with_buffer(&mut self, buffer: &[u32]) {
+    pub fn update_with_buffer(&mut self, buffer: &[u32]) -> Result<()> {
         self.process_events();
         self.key_handler.update();
+
+        let check_res = buffer_helper::check_buffer_size(self.buffer_width, self.buffer_height, self.window_scale, buffer);
+        if check_res.is_err() {
+            return check_res;
+        }
+
         self.render_buffer(buffer);
         self.window.sync();
+
+        Ok(())
     }
 
     pub fn update(&mut self) {

src/os/unix/mod.rs

@@ -19,6 +19,7 @@ use std::ptr;
 use std::mem;
 use std::os::raw;
 use mouse_handler;
+use buffer_helper;
 use window_flags;
 
 #[link(name = "X11")]
@@ -235,6 +236,14 @@ impl Window {
     pub fn update_with_buffer(&mut self, buffer: &[u32]) {
         self.key_handler.update();
 
+        let check_res = buffer_helper::check_buffer_size(self.shared_data.width as usize,
+                                                         self.shared_data.height as usize,
+                                                         self.scale_factor as usize,
+                                                         buffer);
+        if check_res.is_err() {
+            return check_res;
+        }
+
         unsafe {
             Self::set_shared_data(self);
             mfb_update_with_buffer(self.window_handle, buffer.as_ptr() as *const u8);

src/os/windows/mod.rs

@@ -21,6 +21,7 @@ use std::ffi::OsStr;
 use std::mem;
 use std::os::raw;
 use mouse_handler;
+use buffer_helper;
 
 //use self::winapi::windef::HWND;
 //use self::winapi::windef::HDC;
@@ -634,17 +635,27 @@ impl Window {
         }
     }
 
-    pub fn update_with_buffer(&mut self, buffer: &[u32]) {
+    pub fn update_with_buffer(&mut self, buffer: &[u32]) -> Result<()> {
         let window = self.window.unwrap();
 
         Self::generic_update(self, window);
 
+        let check_res = buffer_helper::check_buffer_size(self.width as usize,
+                                                         self.height as usize,
+                                                         self.scale_factor as usize,
+                                                         buffer);
+        if check_res.is_err() {
+            return check_res;
+        }
+
         self.buffer = buffer.to_vec();
         unsafe {
             user32::InvalidateRect(window, ptr::null_mut(), winapi::TRUE);
         }
 
         Self::message_loop(self, window);
+
+        Ok(())
     }
 
     pub fn update(&mut self) {