capi: replace unstable library features with polyfills

Cargo.lock

@@ -1548,6 +1548,7 @@ dependencies = [
  "objc2 0.5.0",
  "paste",
  "rustc-hash",
+ "sptr",
  "thiserror",
  "windows 0.48.0",
 ]

librashader-capi/Cargo.toml

@@ -36,6 +36,7 @@ gl = { version = "0.14.0", optional = true }
 rustc-hash = "1.1.0"
 ash = { version = "0.37", optional = true }
 spirv_cross = { package = "librashader-spirv-cross", version = "0.25.1" }
+sptr = "0.3.2"
 
 [dependencies.librashader]
 path = "../librashader"

librashader-capi/src/error.rs

@@ -206,12 +206,12 @@ impl LibrashaderError {
 
 macro_rules! assert_non_null {
     ($value:ident) => {
-        if $value.is_null() || !$value.is_aligned() {
+        if $value.is_null() || !$crate::ffi::ptr_is_aligned($value) {
             return $crate::error::LibrashaderError::InvalidParameter(stringify!($value)).export();
         }
     };
     (noexport $value:ident) => {
-        if $value.is_null() || !$value.is_aligned() {
+        if $value.is_null() || !$crate::ffi::ptr_is_aligned($value) {
             return Err($crate::error::LibrashaderError::InvalidParameter(
                 stringify!($value),
             ));

librashader-capi/src/ffi.rs

@@ -222,5 +222,25 @@ macro_rules! extern_fn {
     };
 }
 
+pub fn boxed_slice_into_raw_parts<T>(vec: Box<[T]>) -> (*mut T, usize) {
+    let mut me = ManuallyDrop::new(vec);
+    (me.as_mut_ptr(), me.len())
+}
+
+pub unsafe fn boxed_slice_from_raw_parts<T>(ptr: *mut T, len: usize) -> Box<[T]> {
+    unsafe { Box::from_raw(std::slice::from_raw_parts_mut(ptr, len)) }
+}
+
+#[allow(unstable_name_collisions)]
+pub fn ptr_is_aligned<T: Sized>(ptr: *const T) -> bool {
+    use sptr::Strict;
+    let align = std::mem::align_of::<T>();
+    if !align.is_power_of_two() {
+        panic!("is_aligned_to: align is not a power-of-two");
+    }
+    ptr.addr() & (align - 1) == 0
+}
+
 pub(crate) use extern_fn;
 pub(crate) use ffi_body;
+use std::mem::ManuallyDrop;

librashader-capi/src/lib.rs

@@ -65,11 +65,11 @@
 
 #![allow(non_camel_case_types)]
 #![feature(try_blocks)]
-#![feature(pointer_is_aligned)]
-#![feature(vec_into_raw_parts)]
 #![deny(unsafe_op_in_unsafe_fn)]
 #![deny(deprecated)]
 
+extern crate alloc;
+
 pub mod ctypes;
 pub mod error;
 mod ffi;

librashader-capi/src/presets.rs

@@ -218,12 +218,15 @@ extern_fn! {
                 step: param.step
             })
         }
-        let (parts, len, cap) = values.into_raw_parts();
+
+        let values = values.into_boxed_slice();
+        let (parts, len) = crate::ffi::boxed_slice_into_raw_parts(values);
+
         unsafe {
             out.write(MaybeUninit::new(libra_preset_param_list_t {
                 parameters: parts,
                 length: len as u64,
-                _internal_alloc: cap as u64,
+                _internal_alloc: 0,
             }));
         }
     }
@@ -251,9 +254,9 @@ extern_fn! {
     ///   in undefined behaviour.
     fn libra_preset_free_runtime_params(preset: libra_preset_param_list_t) {
         unsafe {
-            let values = Vec::from_raw_parts(preset.parameters.cast_mut(),
-                                             preset.length as usize,
-                                            preset._internal_alloc as usize);
+            let values =
+                    crate::ffi::boxed_slice_from_raw_parts(preset.parameters.cast_mut(),
+                preset.length as usize).into_vec();
 
             for value in values {
                 let name = CString::from_raw(value.name.cast_mut());

test/capi-tests/librashader-capi-tests/librashader-capi-tests/librashader-capi-tests.cpp

@@ -39,7 +39,13 @@ int main()
     libra_preset_param_list_t parameters;
     error = instance.preset_get_runtime_params(&preset, &parameters);
 
-    libra_preset_param_t next = parameters.parameters[471];
+    for (int i = 0; i < parameters.length; i++) {
+        libra_preset_param_t param = parameters.parameters[i];
+
+        printf("%s\n", param.description);
+
+    }
+
 
     instance.preset_free_runtime_params(parameters);