Merge pull request #413 from boozook/fix-sprite-mem-leak

Fix sprite memory leak

Cargo.toml

@@ -23,7 +23,7 @@ lua = { version = "0.1", path = "api/lua", package = "playdate-lua", default-fea
 menu = { version = "0.2", path = "api/menu", package = "playdate-menu", default-features = false }
 scoreboards = { version = "0.1", path = "api/scoreboards", package = "playdate-scoreboards", default-features = false }
 sound = { version = "0.4", path = "api/sound", package = "playdate-sound", default-features = false }
-sprite = { version = "0.2", path = "api/sprite", package = "playdate-sprite", default-features = false }
+sprite = { version = "0.3", path = "api/sprite", package = "playdate-sprite", default-features = false }
 system = { version = "0.3", path = "api/system", package = "playdate-system", default-features = false }
 sys = { version = "0.4", path = "api/sys", package = "playdate-sys", default-features = false }
 

api/playdate/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "playdate"
-version = "0.2.2"
+version = "0.2.3"
 readme = "README.md"
 description = "High-level Playdate API"
 keywords = ["playdate", "sdk", "api", "gamedev"]

api/sprite/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "playdate-sprite"
-version = "0.2.11"
+version = "0.3.0"
 readme = "README.md"
 description = "High-level sprite API built on-top of Playdate API"
 keywords = ["playdate", "sdk", "api", "gamedev"]

api/sprite/src/lib.rs

@@ -1,4 +1,5 @@
 #![cfg_attr(not(test), no_std)]
+#![feature(const_alloc_layout)]
 
 extern crate sys;
 extern crate alloc;
@@ -293,3 +294,45 @@ impl<T: TypedSprite> SpriteType for T {
 	type Userdata = <T as TypedSprite>::Userdata;
 	const FREE_ON_DROP: bool = <T as TypedSprite>::FREE_ON_DROP;
 }
+
+
+pub mod utils {
+	use core::ops::Deref;
+
+	/// C array syzed at runtime.
+	#[must_use]
+	#[repr(transparent)]
+	pub struct Arr<'t, T>(pub(super) &'t [T]);
+
+	impl<T> Drop for Arr<'_, T> {
+		fn drop(&mut self) {
+			let p = self.0.as_ptr() as _;
+
+			#[inline]
+			const fn inner<T>(len: usize) -> core::alloc::Layout {
+				if let Ok(l) = core::alloc::Layout::array::<T>(len) {
+					l
+				} else {
+					use core::mem::{size_of, align_of};
+					let (size, align) = (size_of::<T>(), align_of::<T>());
+					unsafe { core::alloc::Layout::from_size_align_unchecked(size.unchecked_mul(len), align) }
+				}
+			}
+
+			let l = inner::<T>(self.0.len());
+			unsafe {
+				// We could simply `sys::allocator::dealloc(p)`, but we have to use SYSTEM GLOBAL allocator,
+				// which can be a user's custom allocator, not that one in `playdate-sys`.
+				alloc::alloc::dealloc(p, l);
+			};
+		}
+	}
+
+	impl<T> Deref for Arr<'_, T> {
+		type Target = [T];
+		fn deref(&self) -> &Self::Target { self.0 }
+	}
+	impl<T> AsRef<[T]> for Arr<'_, T> {
+		fn as_ref(&self) -> &[T] { self.0 }
+	}
+}

api/sprite/src/sprite.rs

@@ -1,5 +1,15 @@
 //! Sprite implementations.
 
+/*
+TODO: Cover api-methods:
+	- [] querySpritesInRect
+	- [] querySpritesAlongLine
+	- [] querySpriteInfoAlongLine
+	- [] overlappingSprites
+	- [] allOverlappingSprites
+*/
+
+
 use core::ffi::c_int;
 use core::ffi::c_void;
 use core::ffi::c_float;
@@ -18,6 +28,7 @@ use gfx::bitmap::BitmapRef;
 use gfx::bitmap::BitmapDrawMode;
 use gfx::bitmap::BitmapFlip;
 
+use crate::utils;
 use crate::AnySprite;
 use crate::SpriteApi;
 use crate::TypedSprite;
@@ -524,22 +535,22 @@ impl<Userdata, Api: api::Api, const FOD: bool> Sprite<Userdata, Api, FOD> {
 	///
 	/// Equivalent to [`sys::ffi::playdate_sprite::checkCollisions`]
 	#[doc(alias = "sys::ffi::playdate_sprite::check_collisions")]
-	#[must_use = "Result is borrowed by C-API"]
+	#[must_use = "Expensive op, allocated array by C-API"]
 	pub fn check_collisions(&self,
 	                        goal_x: c_float,
 	                        goal_y: c_float,
 	                        actual_x: &mut c_float,
 	                        actual_y: &mut c_float)
-	                        -> &[SpriteCollisionInfo] {
+	                        -> Option<utils::Arr<SpriteCollisionInfo>> {
 		let f = self.1.check_collisions();
 		let mut len: c_int = 0;
 		let ptr = unsafe { f(self.0, goal_x, goal_y, actual_x, actual_y, &mut len) };
 
 		if ptr.is_null() || len == 0 {
-			&[]
+			None
 		} else {
 			let slice = unsafe { core::slice::from_raw_parts(ptr, len as _) };
-			slice
+			Some(utils::Arr(slice))
 		}
 	}
 
@@ -553,22 +564,22 @@ impl<Userdata, Api: api::Api, const FOD: bool> Sprite<Userdata, Api, FOD> {
 	///
 	/// Equivalent to [`sys::ffi::playdate_sprite::moveWithCollisions`]
 	#[doc(alias = "sys::ffi::playdate_sprite::moveWithCollisions")]
-	#[must_use = "Result is borrowed by C-API"]
+	#[must_use = "Expensive op, allocated array by C-API"]
 	pub fn move_with_collisions<'t>(&'t self,
 	                                goal_x: c_float,
 	                                goal_y: c_float,
 	                                actual_x: &mut c_float,
 	                                actual_y: &mut c_float)
-	                                -> &'t [SpriteCollisionInfo] {
+	                                -> Option<utils::Arr<'t, SpriteCollisionInfo>> {
 		let f = self.1.move_with_collisions();
 		let mut len: c_int = 0;
 		let ptr = unsafe { f(self.0, goal_x, goal_y, actual_x, actual_y, &mut len) };
 
 		if ptr.is_null() || len == 0 {
-			&[]
+			None
 		} else {
 			let slice = unsafe { core::slice::from_raw_parts(ptr, len as _) };
-			slice
+			Some(utils::Arr(slice))
 		}
 	}
 
@@ -578,13 +589,18 @@ impl<Userdata, Api: api::Api, const FOD: bool> Sprite<Userdata, Api, FOD> {
 	///
 	/// Equivalent to [`sys::ffi::playdate_sprite::overlappingSprites`]
 	#[doc(alias = "sys::ffi::playdate_sprite::overlapping_sprites")]
-	#[must_use = "Result is borrowed by C-API"]
-	pub fn overlapping_sprites(&self) -> &[SpriteRef] {
+	#[must_use = "Expensive op, allocated array by C-API"]
+	pub fn overlapping_sprites(&self) -> Option<utils::Arr<SpriteRef>> {
 		let f = self.1.overlapping_sprites();
 		let mut len: c_int = 0;
 		let ptr = unsafe { f(self.0, &mut len) };
-		let slice = unsafe { core::slice::from_raw_parts(ptr, len as _) };
-		unsafe { core::mem::transmute(slice) }
+		if ptr.is_null() || len == 0 {
+			None
+		} else {
+			let slice = unsafe { core::slice::from_raw_parts(ptr, len as _) };
+			let res = unsafe { core::mem::transmute(slice) };
+			Some(utils::Arr(res))
+		}
 	}
 
 

api/sys/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "playdate-sys"
-version = "0.4.4"
+version = "0.4.5"
 build = "src/build.rs"
 readme = "README.md"
 description = "Low-level Playdate API bindings"

api/sys/src/sys/allocator.rs

@@ -34,7 +34,7 @@ unsafe impl GlobalAlloc for PlaydateAllocator {
 	#[inline]
 	unsafe fn alloc(&self, layout: Layout) -> *mut u8 { realloc(core::ptr::null_mut(), layout.size()) as *mut u8 }
 	#[inline]
-	unsafe fn dealloc(&self, ptr: *mut u8, _layout: Layout) { realloc(ptr as *mut c_void, 0); }
+	unsafe fn dealloc(&self, ptr: *mut u8, _layout: Layout) { dealloc(ptr as *mut c_void); }
 	#[inline]
 	unsafe fn realloc(&self, ptr: *mut u8, _layout: Layout, new_size: usize) -> *mut u8 {
 		realloc(ptr as *mut c_void, new_size) as *mut u8
@@ -56,3 +56,8 @@ unsafe fn realloc(ptr: *mut c_void, size: usize) -> *mut c_void {
 	               });
 	f(ptr, size)
 }
+
+
+#[track_caller]
+#[inline(always)]
+pub unsafe fn dealloc(ptr: *mut c_void) { realloc(ptr, 0); }