Initial release

Sources/KnotchyCore/Backend/HostEnvironment.swift

@@ -0,0 +1,35 @@
+import Darwin
+import Foundation
+
+public enum HostNetworks {
+    /// Blocked in the VM on top of the private ranges, for LANs and VPNs on public addresses.
+    public static func current() -> [String] {
+        var head: UnsafeMutablePointer<ifaddrs>?
+        guard getifaddrs(&head) == 0, let first = head else { return [] }
+        defer { freeifaddrs(head) }
+        var networks = Set<String>()
+        for pointer in sequence(first: first, next: { $0.pointee.ifa_next }) {
+            let interface = pointer.pointee
+            guard let address = interface.ifa_addr, let mask = interface.ifa_netmask,
+                  address.pointee.sa_family == UInt8(AF_INET),
+                  interface.ifa_flags & UInt32(IFF_LOOPBACK) == 0 else { continue }
+            let ip = address.withMemoryRebound(to: sockaddr_in.self, capacity: 1) { UInt32(bigEndian: $0.pointee.sin_addr.s_addr) }
+            let bits = mask.withMemoryRebound(to: sockaddr_in.self, capacity: 1) { UInt32(bigEndian: $0.pointee.sin_addr.s_addr) }
+            let prefix = bits.nonzeroBitCount
+            guard prefix >= 8 else { continue }   // Never let a bogus /0 block the whole internet.
+            let network = ip & bits
+            networks.insert("\(network >> 24).\((network >> 16) & 0xFF).\((network >> 8) & 0xFF).\(network & 0xFF)/\(prefix)")
+        }
+        return networks.sorted()
+    }
+}
+
+public struct SystemDiskSpace: DiskSpaceChecking {
+    public init() {}
+
+    @concurrent
+    public func bytesFree(atPath path: String) async -> Int64? {
+        let values = try? URL(fileURLWithPath: path).resourceValues(forKeys: [.volumeAvailableCapacityForImportantUsageKey])
+        return values?.volumeAvailableCapacityForImportantUsage
+    }
+}