Closed
Description
openedon Oct 28, 2023
When creating bindings for a struct with bitfields the accessor functions that are created take an immutable receiver (&self). This is a problem if the underlying type is used by both Rust and C, since Rust is not allowed to create &self references, since the C side might modify the value at any time.
One solution could be to create raw accessor functions that allow access via *const Self.
Input C Header
struct foo {
unsigned available:1;
};Bindgen Invocation
$ bindgen input.h
impl foo {
#[inline]
pub fn available(&self) -> ::std::os::raw::c_uint {
unsafe { ::std::mem::transmute(self._bitfield_1.get(0usize, 1u8) as u32) }
}
#[inline]
pub fn set_available(&mut self, val: ::std::os::raw::c_uint) {
unsafe {
let val: u32 = ::std::mem::transmute(val);
self._bitfield_1.set(0usize, 1u8, val as u64)
}
}
#[inline]
pub fn new_bitfield_1(
available: ::std::os::raw::c_uint,
) -> __BindgenBitfieldUnit<[u8; 1usize]> {
let mut __bindgen_bitfield_unit: __BindgenBitfieldUnit<[u8; 1usize]> = Default::default();
__bindgen_bitfield_unit.set(0usize, 1u8, {
let available: u32 = unsafe { ::std::mem::transmute(available) };
available as u64
});
__bindgen_bitfield_unit
}
}Expected Results
Additional functions that should be generated:
impl foo {
#[inline]
pub unsafe fn raw_available(this: *const Self) -> ::std::os::raw::c_uint {
unsafe {
::std::mem::transmute(__BindgenBitfieldUnit::raw_get(
addr_of!((*this)._bitfield_1),
0usize,
1u8,
) as u32)
}
}
#[inline]
pub unsafe fn raw_set_available(this: *mut Self, val: ::std::os::raw::c_uint) {
unsafe {
let val: u32 = ::std::mem::transmute(val);
__BindgenBitfieldUnit::raw_set(addr_of!((*this)._bitfield_1), 0usize, 1u8, val as u64)
}
}
}This also requires changes to the generated __BingenBitfieldUnit.
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