make set_for_current function unsafe

[kitcatier]

Checklist

• tests are passing with cargo test.
• tests and/or benchmarks are included
• documentation is changed or added
• commit message is clear

bastion/src/bastion-executor/src/placement.rs

Lines 20 to 23 in c6016a9

	pub fn set_for_current(core_id: CoreId) {
	tracing::trace!("Executor: placement: set affinity on core {}", core_id.id);
	set_for_current_helper(core_id);
	}

bastion/src/bastion-executor/src/placement.rs

Lines 71 to 86 in c6016a9

	pub fn set_for_current(core_id: CoreId) {
	// Turn `core_id` into a `libc::cpu_set_t` with only
	// one core active.
	let mut set = new_cpu_set();
	unsafe { CPU_SET(core_id.id, &mut set) };
	// Set the current thread's core affinity.
	unsafe {
	sched_setaffinity(
	0, // Defaults to current thread
	mem::size_of::<cpu_set_t>(),
	&set,
	);
	}
	}

bastion/src/bastion-executor/src/placement.rs

Lines 214 to 222 in c6016a9

	pub fn set_for_current(core_id: CoreId) {
	// Convert `CoreId` back into mask.
	let mask: DWORD_PTR = 1 << core_id.id;
	// Set core affinity for current thread.
	unsafe {
	SetThreadAffinityMask(GetCurrentThread(), mask);
	}
	}

Target_OS = "windows"
Hello, in some tests of your bastion_executor project, my program appeared "attempt to shift left with overflow", and the traceback indicated that the set_for_current function in this project crashed when doing a left shift operation.

extern crate bastion_executor;
use bastion_executor::placement::CoreId;
fn main() {
    let a:CoreId = CoreId { id: 771157545605903283 };
    let _ = bastion_executor::placement::set_for_current(a);
}

thread 'main' panicked at 'attempt to shift left with overflow'
stack backtrace: 0: std::panicking::begin_panic_handler at /rustc/73c9eaf21454b718e7c549984d9eb6e1f75e995c/library\std\src\panicking.rs:575 1: core::panicking::panic_fmt at /rustc/73c9eaf21454b718e7c549984d9eb6e1f75e995c/library\core\src\panicking.rs:65 2: core::panicking::panic at /rustc/73c9eaf21454b718e7c549984d9eb6e1f75e995c/library\core\src\panicking.rs:115 3: bastion_executor::placement::windows::set_for_current at C:\Users\.cargo\registry\src\github.com-1ecc6299db9ec823\bastion-executor-0.4.2\src\placement.rs:216 4: bastion_executor::placement::set_for_current_helper at C:\Users\.cargo\registry\src\github.com-1ecc6299db9ec823\bastion-executor-0.4.2\src\placement.rs:180 5: bastion_executor::placement::set_for_current at C:\Users\.cargo\registry\src\github.com-1ecc6299db9ec823\bastion-executor-0.4.2\src\placement.rs:22 6: hello::main at .\src\main.rs:15 7: core::ops::function::FnOnce::call_once<void (*)(),tuple$<> > at /rustc/73c9eaf21454b718e7c549984d9eb6e1f75e995c\library\core\src\ops\function.rs:510
Target_OS = "linux"
thread 'main' panicked at 'index out of bounds: the len is 16 but the index is 12049336650092238'
stack backtrace: 0: rust_begin_unwind at /rustc/8a97b4812a7a46bb5206487c2455b9c5bfcbd1b9/library/std/src/panicking.rs:575:5 1: core::panicking::panic_fmt at /rustc/8a97b4812a7a46bb5206487c2455b9c5bfcbd1b9/library/core/src/panicking.rs:64:14 2: core::panicking::panic_bounds_check at /rustc/8a97b4812a7a46bb5206487c2455b9c5bfcbd1b9/library/core/src/panicking.rs:147:5 3: libc::unix::linux_like::linux::CPU_SET at /home/dl2/.cargo/registry/src/github.com-1ecc6299db9ec823/libc-0.2.139/src/unix/linux_like/linux/mod.rs:3630:9 4: bastion_executor::placement::linux::set_for_current at /home/dl2/.cargo/registry/src/github.com-1ecc6299db9ec823/bastion-executor-0.4.2/src/placement.rs:76:18 5: bastion_executor::placement::set_for_current_helper at /home/dl2/.cargo/registry/src/github.com-1ecc6299db9ec823/bastion-executor-0.4.2/src/placement.rs:44:5 6: bastion_executor::placement::set_for_current at /home/dl2/.cargo/registry/src/github.com-1ecc6299db9ec823/bastion-executor-0.4.2/src/placement.rs:22:5 7: hello_world::main at ./src/main.rs:17:13 8: core::ops::function::FnOnce::call_once at /rustc/8a97b4812a7a46bb5206487c2455b9c5bfcbd1b9/library/core/src/ops/function.rs:507:5
I think it should be marked as unsafe to remind other callers of the real legal input parameters to avoid possible errors.

[o0Ignition0o]

Oh you're right!

I wonder if we should check for CoreId validity before, or make it return a reuslt