extensions/khr: Add ExternalSemaphoreFd safe wrapper

Implement the two small import and export and functions, part of the
VK_KHR_external_semaphore_fd extension.

ash/src/extensions/khr/external_semaphore_fd.rs

@@ -0,0 +1,54 @@
+use crate::prelude::*;
+use crate::version::{DeviceV1_0, InstanceV1_0};
+use crate::vk;
+use std::ffi::CStr;
+use std::mem;
+
+#[derive(Clone)]
+pub struct ExternalSemaphoreFd {
+    handle: vk::Device,
+    external_semaphore_fd_fn: vk::KhrExternalSemaphoreFdFn,
+}
+
+impl ExternalSemaphoreFd {
+    pub fn new<I: InstanceV1_0, D: DeviceV1_0>(instance: &I, device: &D) -> Self {
+        let external_semaphore_fd_fn = vk::KhrExternalSemaphoreFdFn::load(|name| unsafe {
+            mem::transmute(instance.get_device_proc_addr(device.handle(), name.as_ptr()))
+        });
+        Self {
+            handle: device.handle(),
+            external_semaphore_fd_fn,
+        }
+    }
+
+    pub fn name() -> &'static CStr {
+        vk::KhrExternalSemaphoreFdFn::name()
+    }
+
+    #[doc = "<https://www.khronos.org/registry/vulkan/specs/1.2-extensions/man/html/vkImportSemaphoreFdKHR.html>"]
+    pub unsafe fn import_semaphore_fd(
+        &self,
+        import_info: &vk::ImportSemaphoreFdInfoKHR,
+    ) -> VkResult<()> {
+        self.external_semaphore_fd_fn
+            .import_semaphore_fd_khr(self.handle, import_info)
+            .result()
+    }
+
+    #[doc = "<https://www.khronos.org/registry/vulkan/specs/1.2-extensions/man/html/vkGetSemaphoreFdKHR.html>"]
+    pub unsafe fn get_semaphore_fd(&self, get_info: &vk::SemaphoreGetFdInfoKHR) -> VkResult<i32> {
+        let mut fd = -1;
+
+        self.external_semaphore_fd_fn
+            .get_semaphore_fd_khr(self.handle, get_info, &mut fd)
+            .result_with_success(fd)
+    }
+
+    pub fn fp(&self) -> &vk::KhrExternalSemaphoreFdFn {
+        &self.external_semaphore_fd_fn
+    }
+
+    pub fn device(&self) -> vk::Device {
+        self.handle
+    }
+}

ash/src/extensions/khr/mod.rs

@@ -5,6 +5,7 @@ pub use self::display::Display;
 pub use self::display_swapchain::DisplaySwapchain;
 pub use self::draw_indirect_count::DrawIndirectCount;
 pub use self::external_memory_fd::ExternalMemoryFd;
+pub use self::external_semaphore_fd::ExternalSemaphoreFd;
 pub use self::pipeline_executable_properties::PipelineExecutableProperties;
 pub use self::push_descriptor::PushDescriptor;
 pub use self::ray_tracing_pipeline::RayTracingPipeline;
@@ -23,6 +24,7 @@ mod display;
 mod display_swapchain;
 mod draw_indirect_count;
 mod external_memory_fd;
+mod external_semaphore_fd;
 mod pipeline_executable_properties;
 mod push_descriptor;
 mod ray_tracing_pipeline;