Makes a dedicated error type for screen (#1055)

gui/src/vmm/hv/windows/mod.rs

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: MIT OR Apache-2.0
 use self::cpu::WhpCpu;
 use self::partition::Partition;
 use super::{CpuFeats, Hypervisor};

gui/src/vmm/hv/windows/partition.rs

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: MIT OR Apache-2.0
 use super::cpu::WhpCpu;
 use std::ffi::c_void;
 use std::mem::size_of;

gui/src/vmm/kernel/mod.rs

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: MIT OR Apache-2.0
 use std::fs::File;
 use std::io::{Read, Seek, SeekFrom, Take};
 use std::path::Path;

gui/src/vmm/mod.rs

@@ -697,10 +697,6 @@ pub enum DebugResult {
 /// Represents an error when [`vmm_new()`] fails.
 #[derive(Debug, Error)]
 enum VmmError {
-    #[cfg(not(target_os = "macos"))]
-    #[error("couldn't create Vulkan device")]
-    CreateVulkanDeviceFailed(#[source] ash::vk::Result),
-
     #[cfg(target_os = "windows")]
     #[error("couldn't create WHP partition object ({0:#x})")]
     CreatePartitionFailed(windows_sys::core::HRESULT),
@@ -736,10 +732,6 @@ enum VmmError {
     #[cfg(target_os = "macos")]
     #[error("couldn't map memory to the VM ({0:#x})")]
     MapRamFailed(NonZero<applevisor_sys::hv_return_t>),
-
-    #[cfg(target_os = "macos")]
-    #[error("couldn't get default MTLDevice")]
-    GetMetalDeviceFailed,
 }
 
 /// Represents an error when [`main_cpu()`] fails to reach event loop.

gui/src/vmm/screen/metal/mod.rs

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT OR Apache-2.0
 use self::buffer::MetalBuffer;
-use super::{Screen, ScreenBuffer, VmmError};
+use super::{Screen, ScreenBuffer};
 use crate::vmm::VmmScreen;
 use metal::{CAMetalLayer, Device, MetalLayer};
 use objc::runtime::{Object, NO, YES};
@@ -22,11 +22,11 @@ pub struct Metal {
 }
 
 impl Metal {
-    pub fn new(screen: &VmmScreen) -> Result<Self, VmmError> {
+    pub fn new(screen: &VmmScreen) -> Result<Self, MetalError> {
         // Get Metal device.
         let device = match Device::system_default() {
             Some(v) => v,
-            None => return Err(VmmError::GetMetalDeviceFailed),
+            None => return Err(MetalError::GetDeviceFailed),
         };
 
         // Setup Metal layer.
@@ -70,6 +70,13 @@ impl Screen for Metal {
     }
 }
 
+/// Represents an error when [`Metal::new()`] fails.
+#[derive(Debug, Error)]
+pub enum MetalError {
+    #[error("couldn't get default MTLDevice")]
+    GetDeviceFailed,
+}
+
 /// Implementation of [`Screen::UpdateErr`].
 #[derive(Debug, Error)]
 pub enum UpdateError {}

gui/src/vmm/screen/mod.rs

@@ -1,17 +1,16 @@
-use super::VmmError;
+// SPDX-License-Identifier: MIT OR Apache-2.0
 use std::error::Error;
 use std::sync::Arc;
 
-#[cfg(target_os = "macos")]
-mod metal;
-#[cfg(not(target_os = "macos"))]
-mod vulkan;
+#[cfg_attr(target_os = "macos", path = "metal/mod.rs")]
+#[cfg_attr(not(target_os = "macos"), path = "vulkan/mod.rs")]
+mod engine;
 
 #[cfg(not(target_os = "macos"))]
-pub type Default = self::vulkan::Vulkan;
+pub type Default = self::engine::Vulkan;
 
 #[cfg(target_os = "macos")]
-pub type Default = self::metal::Metal;
+pub type Default = self::engine::Metal;
 
 /// Encapsulates a platform-specific surface for drawing a VM screen.
 pub trait Screen: 'static {

gui/src/vmm/screen/vulkan/mod.rs

@@ -14,7 +14,7 @@ use self::ffi::{
     get_physical_device_sparse_image_format_properties,
     get_physical_device_sparse_image_format_properties2, get_physical_device_tool_properties,
 };
-use super::{Screen, ScreenBuffer, VmmError};
+use super::{Screen, ScreenBuffer};
 use crate::vmm::VmmScreen;
 use ash::vk::{DeviceCreateInfo, DeviceQueueCreateInfo, Handle, QueueFlags};
 use ash::{Device, Instance, InstanceFnV1_0, InstanceFnV1_1, InstanceFnV1_3};
@@ -31,7 +31,7 @@ pub struct Vulkan {
 }
 
 impl Vulkan {
-    pub fn new(screen: &VmmScreen) -> Result<Self, VmmError> {
+    pub fn new(screen: &VmmScreen) -> Result<Self, VulkanError> {
         // Wrap VkInstance.
         let instance = screen.vk_instance.try_into().unwrap();
         let instance = ash::vk::Instance::from_raw(instance);
@@ -87,7 +87,7 @@ impl Vulkan {
         let device = DeviceCreateInfo::default().queue_create_infos(&queues);
         let device = match unsafe { instance.create_device(physical, &device, None) } {
             Ok(v) => v,
-            Err(e) => return Err(VmmError::CreateVulkanDeviceFailed(e)),
+            Err(e) => return Err(VulkanError::CreateDeviceFailed(e)),
         };
 
         Ok(Self {
@@ -100,7 +100,7 @@ impl Vulkan {
         _: ash::vk::Instance,
         _: *const ash::vk::AllocationCallbacks<'_>,
     ) {
-        unreachable!();
+        unimplemented!()
     }
 }
 
@@ -124,6 +124,13 @@ impl Screen for Vulkan {
     }
 }
 
+/// Represents an error when [`Vulkan::new()`] fails.
+#[derive(Debug, Error)]
+pub enum VulkanError {
+    #[error("couldn't create a logical device")]
+    CreateDeviceFailed(#[source] ash::vk::Result),
+}
+
 /// Implementation of [`Screen::UpdateErr`].
 #[derive(Debug, Error)]
 pub enum UpdateError {}