Merge pull request #337: Fix panic & error, improve allocator (#335…

…, #336)

- Fix `abort` and `panic` to do not crash simulator process (#335)
- Improve global allocator, cache fn-ptr to OS's `realloc` (#336)

api/sys/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "playdate-sys"
-version = "0.3.5"
+version = "0.3.6"
 build = "src/build.rs"
 readme = "README.md"
 description = "Low-level Playdate API bindings"

api/sys/src/sys/allocator.rs

@@ -25,7 +25,7 @@ pub static GLOBAL: PlaydateAllocator = PlaydateAllocator;
 /// Global handler for an Out Of Memory (OOM) condition
 #[alloc_error_handler]
 #[cfg(feature = "allocator")]
-fn alloc_error(_layout: Layout) -> ! { panic!("Out of Memory") }
+fn alloc_error(layout: Layout) -> ! { panic!("Out of Memory, requested {}.", layout.size()) }
 
 
 pub struct PlaydateAllocator;
@@ -42,13 +42,17 @@ unsafe impl GlobalAlloc for PlaydateAllocator {
 }
 
 
-fn realloc(ptr: *mut c_void, size: usize) -> *mut c_void {
-	unsafe {
-		if let Some(api) = crate::sys::API.as_ref() {
-			if let Some(f) = (*api.system).realloc {
-				return f(ptr, size);
-			}
-		}
-	}
-	panic!("realloc")
+#[track_caller]
+unsafe fn realloc(ptr: *mut c_void, size: usize) -> *mut c_void {
+	// Cached pointer to the OS's realloc function.
+	static mut REALLOC: Option<unsafe extern "C" fn(ptr: *mut c_void, size: usize) -> *mut c_void> = None;
+
+	let f = REALLOC.get_or_insert_with(|| {
+		               if let Some(realloc) = crate::sys::API.as_ref().and_then(|api| (*api.system).realloc) {
+			               realloc
+		               } else {
+			               panic!("Missed API.realloc")
+		               }
+	               });
+	f(ptr, size)
 }

api/sys/src/sys/proc.rs

@@ -1,11 +1,15 @@
 //! Process API. Abort and abort with error message.
 
 /// Executes the undefined instruction (UDF) and causes a CPU-level exception.
-/// See [`core::intrinsics::abort()`]
+/// See [`core::intrinsics::abort()`].
+#[track_caller]
+#[inline(always)]
 pub fn abort() -> ! { core::intrinsics::abort() }
 
 
 /// Stops the program execution with custom system-level error.
+///
+/// In case of missed [`crate::sys::API`] (doesn't set) uses [`abort`].
 #[track_caller]
 pub fn error<S: AsRef<str>>(text: S) -> ! {
 	if let Some(f) = unsafe { (*(*crate::sys::API).system).error } {
@@ -14,9 +18,13 @@ pub fn error<S: AsRef<str>>(text: S) -> ! {
 		} else {
 			unsafe { f(text.as_ref().as_ptr() as *mut core::ffi::c_char) }
 		}
+		loop {
+			// This is unreachable or the device,
+			// `API.system.error` interrupts the execution.
+			// But simulator doesn't stops on `error`, so just spin-loop here.
+		}
+	} else {
+		// In case of `crate::sys::API` is missed (doesn't set) just abort the process.
+		abort()
 	}
-	// Next line is mostly unreachable,
-	// but in some cases such as some versions of simulator doesn't stops on `error`,
-	// especially in case of `crate::sys::API` isn't filled.
-	abort()
 }