Simulator Architecture Detector

Architecture.swift

//
//  Architecture.swift
//  TumblrSnapshotTestCase
//
//  Created by Declan McKenna on 26/01/2022.
//

import Foundation

@objc(PSTArchitecture) public final class Architecture: NSObject { // @arnold no-tests
    /// Check if process runs under Rosetta 2.
    /// https://developer.apple.com/forums/thread/652667?answerId=618217022&page=1#622923022
    /// https://developer.apple.com/documentation/apple-silicon/about-the-rosetta-translation-environment
    @objc public static var isRosettaEmulated: Bool {
        #if targetEnvironment(simulator)
        return processIsTranslated() == EMULATED_EXECUTION
        #else
        return false
        #endif
    }
    
    /// Returns true on M1 macs and false on intel machines or M1 macs using Rosetta
    public static var isArm64: Bool {
        #if arch(arm64)
        return true
        #else
        return false
        #endif
    }
    
    /// Returns "arm64" or "x86_64" String based on architecture of current macbook
    public static var current: String { isArm64 ? "arm64" : "x86_64" }
}

fileprivate let NATIVE_EXECUTION = Int32(0)
fileprivate let EMULATED_EXECUTION = Int32(1)
fileprivate let UNKNOWN_EXECUTION = -Int32(1)

private func processIsTranslated() -> Int32 {
    let key = "sysctl.proc_translated"
    var ret = Int32(0)
    var size: Int = 0
    sysctlbyname(key, nil, &size, nil, 0)
    let result = sysctlbyname(key, &ret, &size, nil, 0)
    if result == -1 {
        if errno == ENOENT {
            return 0
        }
        return -1
    }
    return ret
}