Support fixed-size array parameters #1941
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I used BCrypt to validate a lot of this work. https://github.com/microsoft/windows-rs/blob/fixed-arrays/crates/tests/bcrypt/tests/tests.rs It's now a lot easier to reason about and use such APIs from Rust thanks to the awareness of optional and array parameters. |
| } | ||
| quote! { #name.as_ptr() } | ||
| }; | ||
| quote! { ::core::mem::transmute(#map), } |
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Since we know this is a pointer does as _ work instead? Would be nice to avoid another use of transmute.
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Not just yet - it still requires a bit more untangling before that will work. There are a few cases where the underlying types aren't simply the pointer equivalent of the slice. But I'd love to get there.
| pub const fn trim_null_end(mut bytes: &[u8]) -> &[u8] { | ||
| while let [rest @ .., last] = bytes { | ||
| if *last == 0 { | ||
| bytes = rest; | ||
| } else { | ||
| break; | ||
| } | ||
| } | ||
| bytes | ||
| } |
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Is there a reason this is const?
Could be rewritten as:
fn trim_null_end(bytes: &[u8]) -> &[u8] {
let end = bytes
.iter()
.rposition(|&s| s != 0)
.map(|i| i + 1)
.unwrap_or(bytes.len());
&bytes[..end]
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It doesn't but the iterator approach seems overly complicated in comparison.
Following on #1939 this update adds support for Win32 parameters that are declared as fixed-size arrays. This avoid any confusion around treating these arrays as references. It also more consistently applies
Optionto optional parameters rather than trying to transform empty slices into null pointers under the hood.Unfortunately, it also highlighted a few more metadata bugs:
microsoft/win32metadata#1008
microsoft/win32metadata#1010
microsoft/win32metadata#1011
microsoft/win32metadata#1012
microsoft/win32metadata#1014
Fixes #1938