I've read that pointer arithmetic in Rust can be done through the pointer.offset()
function, but it always has to be implemented in unsafe code
:
fn main() {
let buf: [u32; 5] = [1, 2, 3, 4, 5];
let mut ptr1: *const u32 = buf.as_ptr();
unsafe {
let ptr2: *const u32 = buf.as_ptr().offset(buf.len() as isize);
while ptr1 < ptr2 {
println!("Address {:?} | Value {}", ptr1, *ptr1);
ptr1 = ptr1.offset(1);
}
}
}
If I want to code in Rust securely, should I code without using pointer arithmetic and just using the corresponding index of an array for example? Or is there any other way?
If I want to code in Rust securely
Then you should not use unsafe
. There are a few legit reasons for unsafe
(e.g. accessing memory locations that are known and safe to use, e.g. on microcontrollers several registers), but generally you should not use it.
should I code without using pointer arithmetic and just using the corresponding index of an array for example
Yes. There is no reason (in this specific case) to use unsafe
at all. Just use
for i in 0..buf.len() {
println!("Value {}", buf[i]);
}
This code however is not considered as "rusty", instead use a for-loop
for i in &buf {
println!("Value {}", i);
}