capi: extend config_struct macro to handle overrides

This commit is contained in:
chyyran 2024-02-26 22:18:12 -05:00 committed by Ronny Chan
parent 9b40c10466
commit 321e30a0f1

View file

@ -146,29 +146,85 @@ where
} }
macro_rules! config_set_field { macro_rules! config_set_field {
($options:ident.$field:ident <- $ptr:ident) => { (@POINTER $options:ident.$field:ident <- $ptr:ident) => {
$options.$field = unsafe { ::std::ptr::addr_of!((*$ptr).$field).read() }; $options.$field = unsafe { ::std::ptr::addr_of!((*$ptr).$field).read() };
}; };
(@POINTER @NEGATIVE $options:ident.$field:ident <- $ptr:ident) => {
$options.$field = unsafe { !::std::ptr::addr_of!((*$ptr).$field).read() };
};
(@LITERAL $options:ident.$field:ident <- $value:literal) => {
$options.$field = $value;
};
} }
macro_rules! config_version_set { macro_rules! config_version_set {
($version:literal => [$($field:ident),+ $(,)?] ($options:ident <- $ptr:ident)) => { // "optimized" version for normal behaviour
let version = unsafe { ::std::ptr::addr_of!((*$ptr).version).read() }; (@ROOT $realver:ident $version:literal => [$($field:ident),+ $(,)?] ($options:ident <- $ptr:ident)) => {
#[allow(unused_comparisons)] #[allow(unused_comparisons)]
if version >= $version { if $realver >= $version {
$($crate::ctypes::config_set_field!($options.$field <- $ptr);)+ $($crate::ctypes::config_set_field!(@POINTER $options.$field <- $ptr);)+
} }
};
// Repeater
(@ROOT $realver:ident $version:literal => [$($field:tt),+ $(,)?] ($options:ident <- $ptr:ident)) => {
$(crate::ctypes::config_version_set!(@SINGLE $realver $version => [$field] ($options <- $ptr));)+
};
// Allow overriding default value with a literal for older versions
(@SINGLE $realver:ident $version:literal => [($field:ident: $value:literal)] ($options:ident <- $ptr:ident)) => {
#[allow(unused_comparisons)]
if $realver >= $version {
$crate::ctypes::config_set_field!(@LITERAL $options.$field <- $value);
} }
};
// Allow negation of prior variables that is version dependent.
(@SINGLE $realver:ident $version:literal => [(!$field:ident)] ($options:ident <- $ptr:ident)) => {
#[allow(unused_comparisons)]
if $realver >= $version {
$crate::ctypes::config_set_field!(@POINTER @NEGATIVE $options.$field <- $ptr);
}
};
(@SINGLE $realver:ident $version:literal => [$field:ident] ($options:ident <- $ptr:ident)) => {
#[allow(unused_comparisons)]
if $realver >= $version {
$crate::ctypes::config_set_field!(@POINTER $options.$field <- $ptr);
}
};
} }
/// Macro to declare a configuration struct, with options to change behaviour based on
/// API version.
///
/// For example following declaration does the following
///
/// * Declare `frames_in_flight`, `use_dynamic_rendering` for API version 0, with the following forward compatibility statements
/// * Inverts the behaviour of `use_dynamic_rendering` compared to API version 1.
/// * `disable_cache` is defaulted to `true` for API version 0, regardless of `Default::default`
/// but is not declared for API 0.
/// * Declare `use_dynamic_rendering` with normal behaviour, and `disable_cache` for API version 1.
/// * All fields that are undeclared inherit `Default::default`
///
/// ```rust
/// config_struct! {
/// impl FilterChainOptions => filter_chain_vk_opt_t {
/// 0 => [frames_in_flight, (!use_dynamic_rendering), (disable_cache: true)];
/// 1 => [use_dynamic_rendering, disable_cache];
/// }
/// }
/// ```
macro_rules! config_struct { macro_rules! config_struct {
(impl $rust:ty => $capi:ty {$($version:literal => [$($field:ident),+ $(,)?]);+ $(;)?}) => { (impl $rust:ty => $capi:ty {$($version:literal => [$($field:tt),+]);+ $(;)?}) => {
impl $crate::ctypes::FromUninit<$rust> for $capi { impl $crate::ctypes::FromUninit<$rust> for $capi {
fn from_uninit(value: ::std::mem::MaybeUninit<Self>) -> $rust { fn from_uninit(value: ::std::mem::MaybeUninit<Self>) -> $rust {
let ptr = value.as_ptr(); let ptr = value.as_ptr();
let version = unsafe { ::std::ptr::addr_of!((*ptr).version).read() };
let mut options = <$rust>::default(); let mut options = <$rust>::default();
$( $(
$crate::ctypes::config_version_set!($version => [$($field),+] (options <- ptr)); $crate::ctypes::config_version_set!(@ROOT version $version => [$($field),+] (options <- ptr));
)+ )+
options options
} }