From 073c0b2f3e704de9bf85df7ad37cb8e60e44f818 Mon Sep 17 00:00:00 2001
From: Connor Fitzgerald <connorwadefitzgerald@gmail.com>
Date: Mon, 21 Dec 2020 14:30:55 -0500
Subject: [PATCH] Validate swapchain extent as non-zero

---
 wgpu-core/src/device/mod.rs | 8 ++++++--
 wgpu-core/src/swap_chain.rs | 2 ++
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/wgpu-core/src/device/mod.rs b/wgpu-core/src/device/mod.rs
index e5e61c0f02..0e9f2493c3 100644
--- a/wgpu-core/src/device/mod.rs
+++ b/wgpu-core/src/device/mod.rs
@@ -3847,7 +3847,7 @@ impl<G: GlobalIdentityHandlerFactory> Global<G> {
         fn validate_swap_chain_descriptor(
             config: &mut hal::window::SwapchainConfig,
             caps: &hal::window::SurfaceCapabilities,
-        ) {
+        ) -> Result<(), swap_chain::CreateSwapChainError> {
             let width = config.extent.width;
             let height = config.extent.height;
             if width < caps.extents.start().width
@@ -3870,6 +3870,10 @@ impl<G: GlobalIdentityHandlerFactory> Global<G> {
                 );
                 config.present_mode = hal::window::PresentMode::FIFO;
             }
+            if width == 0 || height == 0 {
+                return Err(swap_chain::CreateSwapChainError::ZeroArea);
+            }
+            Ok(())
         }
 
         tracing::info!("creating swap chain {:?}", desc);
@@ -3911,7 +3915,7 @@ impl<G: GlobalIdentityHandlerFactory> Global<G> {
                 });
             }
         }
-        validate_swap_chain_descriptor(&mut config, &caps);
+        validate_swap_chain_descriptor(&mut config, &caps)?;
 
         unsafe {
             B::get_surface_mut(surface)
diff --git a/wgpu-core/src/swap_chain.rs b/wgpu-core/src/swap_chain.rs
index b6c7fa7497..e2ece136f6 100644
--- a/wgpu-core/src/swap_chain.rs
+++ b/wgpu-core/src/swap_chain.rs
@@ -91,6 +91,8 @@ pub enum CreateSwapChainError {
     InvalidSurface,
     #[error("`SwapChainOutput` must be dropped before a new `SwapChain` is made")]
     SwapChainOutputExists,
+    #[error("Both `SwapChain` width and height must be non-zero. Wait to recreate the `SwapChain` until the window has non-zero area.")]
+    ZeroArea,
     #[error("surface does not support the adapter's queue family")]
     UnsupportedQueueFamily,
     #[error("requested format {requested:?} is not in list of supported formats: {available:?}")]