Merge pull request #3221 from Tetralux/net/reservedports

[net] Better error code for binding a privileged port without root access

core/net/errors_darwin.odin

@@ -34,7 +34,7 @@ Create_Socket_Error :: enum c.int {
 
 Dial_Error :: enum c.int {
 	None                      = 0,
-	Port_Required             = -1,
+	Port_Required             = -1, // Attempted to dial an endpointing without a port being set.
 
 	Address_In_Use            = c.int(os.EADDRINUSE),
 	In_Progress               = c.int(os.EINPROGRESS),
@@ -54,7 +54,9 @@ Dial_Error :: enum c.int {
 }
 
 Bind_Error :: enum c.int {
-	None                    = 0,
+	None                         = 0,
+	Privileged_Port_Without_Root = -1, // Attempted to bind to a port less than 1024 without root access.
+
 	Address_In_Use          = c.int(os.EADDRINUSE),    // Another application is currently bound to this endpoint.
 	Given_Nonlocal_Address  = c.int(os.EADDRNOTAVAIL), // The address is not a local address on this machine.
 	Broadcast_Disabled      = c.int(os.EACCES),        // To bind a UDP socket to the broadcast address, the appropriate socket option must be set.

core/net/socket_darwin.odin

@@ -92,13 +92,20 @@ _dial_tcp_from_endpoint :: proc(endpoint: Endpoint, options := default_tcp_optio
 	return
 }
 
+// On Darwin, any port below 1024 is 'privileged' - which means that you need root access in order to use it.
+MAX_PRIVILEGED_PORT :: 1023
+
 @(private)
 _bind :: proc(skt: Any_Socket, ep: Endpoint) -> (err: Network_Error) {
 	sockaddr := _endpoint_to_sockaddr(ep)
 	s := any_socket_to_socket(skt)
 	res := os.bind(os.Socket(s), (^os.SOCKADDR)(&sockaddr), i32(sockaddr.len))
 	if res != os.ERROR_NONE {
-		err = Bind_Error(res)
+		if res == os.EACCES && ep.port <= MAX_PRIVILEGED_PORT {
+			err = .Privileged_Port_Without_Root
+		} else {
+			err = Bind_Error(res)
+		}
 	}
 	return
 }