Question

struct CirBuffer {
    buf: [u8; 256],
    lowest_mem_addr: *const u8,
    highest_mem_addr: *const u8,
    is_empty: bool,
    is_full: bool,
}

构造项目lowest_mem_addr 是佩戴面罩。

impl CirBuffer 页: 1

fn create () -> Self{
    CirBuffer {
        buf: [0;256],
        lowest_mem_addr: &(*self).buf[0],=> How to get the address of buf[0] here ?
        highest_mem_addr: &self.buf[255],

Answer 1

也许我没有东西,但难道这只是一个在结构之外宣布缓冲的问题吗?

struct CirBuffer {
    buf: [u8; 256],
    lowest_mem_addr: *const u8,
    highest_mem_addr: *const u8,
    is_empty: bool,
    is_full: bool,
}

impl CirBuffer {
    fn create() -> Self {
        let buf = [0; 256];

        CirBuffer {
            buf,
            lowest_mem_addr: &buf[0],
            highest_mem_addr: &buf[255],
            is_empty: true,
            is_full: false,
        }
    }
}

Answer 2

简言之,由于同样的原因,自食其力的建筑不奏效。

Rust的任何类型都假定是三维的动产,即,你总是可以打电话到<条码>>mcpy on thelying bytes,忘记了原样,并且将本拷贝用作正本,而且一切工作都应该是作为人。但是,如果你认为你的点人是有效的(如果你重新创建,为什么会 t你?),那就会打破——点人仍将指老的立场,现在这种立场正在 d。

取决于你想要的:

Just use VecDeque. It would be good enough for many practical cases.
Put the buffer on the heap, as Box<[u8; 256]>. In this case, you must be careful not to move this buffer out of the box - in particular, you must never expose a mutable reference to buf, since caller might then simply mem::swap it. There might be another considerations - I m not an expert with unsafe code, better have a review from more experienced programmers.
Use indices instead of pointers. You might want to store them as u8 and use buf[idx as usize], since in this case bound checks will be optimized away - check "Show Assembly" in this playground.

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