Struct repr_offset::offset_calc::GetNextFieldOffset

pub struct GetNextFieldOffset {
    pub previous_offset: usize,
    pub previous_size: usize,
    pub container_alignment: usize,
    pub next_alignment: usize,
}

Calculates the offset (in bytes) of a field, with the call method.

Example

use repr_offset::offset_calc::GetNextFieldOffset;

use std::mem;

#[repr(C, packed)]
struct Foo(u8, u16, u32, u64);

assert_eq!( OFFSET_1, 1 );
assert_eq!( OFFSET_2, 3 );
assert_eq!( OFFSET_3, 7 );

const OFFSET_0: usize = 0;

const OFFSET_1: usize = GetNextFieldOffset{
    previous_offset: OFFSET_0,
    previous_size: mem::size_of::<u8>(),
    container_alignment: mem::align_of::<Foo>(),
    next_alignment: mem::align_of::<u16>(),
}.call();

const OFFSET_2: usize = GetNextFieldOffset{
    previous_offset: OFFSET_1,
    previous_size: mem::size_of::<u16>(),
    container_alignment: mem::align_of::<Foo>(),
    next_alignment: mem::align_of::<u32>(),
}.call();

const OFFSET_3: usize = GetNextFieldOffset{
    previous_offset: OFFSET_2,
    previous_size: mem::size_of::<u32>(),
    container_alignment: mem::align_of::<Foo>(),
    next_alignment: mem::align_of::<u64>(),
}.call();

Fields

previous_offset: usize

The offset in bytes of the previous field.

previous_size: usize

The size of the previous field.

container_alignment: usize

The alignment of the type that contains the field.

next_alignment: usize

The alignment of the field that this calculates the offset for.

Implementations

impl GetNextFieldOffset

pub const fn call(self) -> usize

Calculates the offset (in bytes) of a field.