Struct ashpan::GuardedResource

pub struct GuardedResource<'a, Resource, Destroyer>(_)
 where
    Resource: Destroyable,
    Destroyer: Deref<Target = <Resource as Destroyable>::Destroyer>;

ScopeGuard tailored for Vulkan

When the GuardedResource is dropped, the contained Resource is destroyed, generally by calling an appropriate method on the Destroyer (usually an &ash::Device) with allocation_callbacks. The contained resource can be accessed by dereferencing or extracted with .take(). Application-specific types are supported if they implement Destroyable. The Guarded alias is provided for the common use-case where Destroyer is &ash::Device.

use ash::{prelude::VkResult, vk};
use ashpan::{DeviceExt, Guarded};

unsafe fn create_pipeline(device: &ash::Device) -> VkResult<Guarded<vk::Pipeline>> {
    let pipeline_cache = unimplemented!();
    let create_info = unimplemented!();

    // Because the returned pipelines are wrapped in a GuardedResource,
    // they don't leak when dropped by .map_err()
    let pipelines = device
        .create_guarded_graphics_pipelines(pipeline_cache, &[create_info], None)
        .map_err(|(_, err)| err)?;

    assert_eq!(pipelines.len(), 1);
    let pipeline = pipelines.take()[0];
    // This would also work:
    // let pipeline = pipelines.pop().unwrap();

    Ok(Guarded::new(pipeline, device, None))
}

Implementations

impl<'a, Resource, Destroyer> GuardedResource<'a, Resource, Destroyer> where
    Resource: Destroyable,
    Destroyer: Deref<Target = <Resource as Destroyable>::Destroyer>, 

pub unsafe fn new(
    resource: Resource,
    destroyer: Destroyer,
    allocation_callbacks: Option<&'a AllocationCallbacks>
) -> Self

Creates a GuardedResource to hold the passed resource. destroyer and allocation_callbacks are used during destruction.

Safety

You must ensure that it is safe to destroy resource when the GuardedResource is dropped.

pub fn take(self) -> Resource

Extract the inner value without destroying it.

Note

Unlike ScopeGuard::into_inner, this is a method because it’s not intended to work with arbitrary types, so avoiding shadowing .take() is less important than convenience.

Trait Implementations

impl<'a, Resource, Destroyer> AsMut<Resource> for GuardedResource<'a, Resource, Destroyer> where
    Resource: Destroyable,
    Destroyer: Deref<Target = <Resource as Destroyable>::Destroyer>, 

fn as_mut(&mut self) -> &mut Resource

Performs the conversion.

impl<'a, Resource, Destroyer> AsRef<Resource> for GuardedResource<'a, Resource, Destroyer> where
    Resource: Destroyable,
    Destroyer: Deref<Target = <Resource as Destroyable>::Destroyer>, 

fn as_ref(&self) -> &Resource

Performs the conversion.

impl<'a, Resource, Destroyer> Borrow<Resource> for GuardedResource<'a, Resource, Destroyer> where
    Resource: Destroyable,
    Destroyer: Deref<Target = <Resource as Destroyable>::Destroyer>, 

fn borrow(&self) -> &Resource

Immutably borrows from an owned value.

impl<'a, Resource, Destroyer> BorrowMut<Resource> for GuardedResource<'a, Resource, Destroyer> where
    Resource: Destroyable,
    Destroyer: Deref<Target = <Resource as Destroyable>::Destroyer>, 

fn borrow_mut(&mut self) -> &mut Resource

Mutably borrows from an owned value.

impl<'a, Resource: Debug, Destroyer: Debug> Debug for GuardedResource<'a, Resource, Destroyer> where
    Resource: Destroyable,
    Destroyer: Deref<Target = <Resource as Destroyable>::Destroyer>, 

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'a, Resource, Destroyer> Deref for GuardedResource<'a, Resource, Destroyer> where
    Resource: Destroyable,
    Destroyer: Deref<Target = <Resource as Destroyable>::Destroyer>, 

type Target = Resource

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<'a, Resource, Destroyer> DerefMut for GuardedResource<'a, Resource, Destroyer> where
    Resource: Destroyable,
    Destroyer: Deref<Target = <Resource as Destroyable>::Destroyer>, 

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl<'a, Resource, Destroyer> Drop for GuardedResource<'a, Resource, Destroyer> where
    Resource: Destroyable,
    Destroyer: Deref<Target = <Resource as Destroyable>::Destroyer>, 

fn drop(&mut self)

Executes the destructor for this type.