Added userName and fullUserName to ProcessInfo

[pvieito]

• Added ProcessInfo.userName and ProcessInfo.fullUserName as in Darwin Foundation
• Added NSFullUserName() as in Darwin Foundation
• Added underlying implementation in Core Foundation CFCopyFullUserName() for POSIX OS.

[spevans]

Could you use something like the following to extract the gecos info?

public func NSFullUserName() -> String {
    let euid = _CFGetEUID()
    let uid = euid != 0 ? euid : getuid()
    var pwd = passwd()
    let maxSize = sysconf(Int32(_SC_GETPW_R_SIZE_MAX))
    let buf = UnsafeMutablePointer<Int8>.allocate(capacity: maxSize)
    defer { buf.deallocate() }
    var ptr: UnsafeMutablePointer<passwd>? = nil
    if getpwuid_r(uid, &pwd, buf, maxSize, &ptr) == 0 {
        if let gecos = pwd.pw_gecos {
            return String(cString: gecos)
        }
    }

    return ""
}

[pvieito]

I would prefer to leave the NSFullUserName implementation for other Pull Request/Contributor.

[pvieito]

Thinking about this, shouldn't this code be implemented in Core Foundation in a function similar to CFCopyUserName and made portable between multiple platforms?

[spevans]

I would probably keep it in Swift and only add it into CF if the multi-platform support became too messy and a lot easier to write using the C preprocessor.

[pvieito]

Added NSFullUserName() and underlying implementation in CFCopyFullUserName() for POSIX OS.

[parkera]

Style nit here: please always use { } or make one line for if statements.

[parkera]

Other than minor style point, looks good to me.

[pvieito]

Updated style with braces on if statements.

[parkera]

@swift-ci test and merge

[spevans]

@swift-ci test and merge