memory-layout
is a minimal no_std
compatible crate that allows you to specify the memory layout of a struct, similarly to C#'s [StructLayout(LayoutKind.Explicit)]
.
https://docs.rs/memory-layout/
- Specify the offset a field should have in a struct.
- Offsets are checked to be valid at compile time.
no_std
compatible.
use memory_layout::memory_layout;
#[memory_layout]
pub struct Example {
#[field_offset(0x00)]
a: i32,
#[field_offset(0x10)]
b: u64,
#[field_offset(0x20)]
c: f32
}
Will expand to:
pub struct Example {
#[doc(hidden)]
__pad0: [u8; 0usize],
a: i32,
#[doc(hidden)]
__pad1: [u8; 16usize - ::core::mem::size_of::<i32>()],
b: u64,
#[doc(hidden)]
__pad2: [u8; 8usize - ::core::mem::size_of::<u64>()],
c: f32
}
- Fields have to be defined in ascending order by the specified offset.
#[memory_layout]
attribute has to be defined before anyderive
attributes.
This project has a similar goal to this crate, replicating C#'s [StructLayout(LayoutKind.Explicit)]
. The key difference is that struct_layout
uses an internal array that can be accessed using methods like get_<field_name>
and set_<field_name>
while this crate aligns the fields themselves.