Add socket operations

builtins/connect.go

@@ -0,0 +1,50 @@
+package builtins
+
+import (
+	"monkey/object"
+	"monkey/typing"
+	"syscall"
+)
+
+// Connect ...
+func Connect(args ...object.Object) object.Object {
+	if err := typing.Check(
+		"connect", args,
+		typing.ExactArgs(2),
+		typing.WithTypes(object.INTEGER_OBJ, object.STRING_OBJ),
+	); err != nil {
+		return newError(err.Error())
+	}
+
+	var sa syscall.Sockaddr
+
+	fd := int(args[0].(*object.Integer).Value)
+	address := args[1].(*object.String).Value
+
+	sockaddr, err := syscall.Getsockname(syscall.Handle(fd))
+	if err != nil {
+		return newError("ValueError: %s", err)
+	}
+
+	if _, ok := sockaddr.(*syscall.SockaddrInet4); ok {
+		addr, port, err := parseV4Address(address)
+		if err != nil {
+			return newError("ValueError: Invalid IPv4 address '%s': %s", address, err)
+		}
+		sa = &syscall.SockaddrInet4{Addr: addr, Port: port}
+	} else if _, ok := sockaddr.(*syscall.SockaddrInet6); ok {
+		addr, port, err := parseV6Address(address)
+		if err != nil {
+			return newError("ValueError: Invalid IPv6 address '%s': %s", address, err)
+		}
+		sa = &syscall.SockaddrInet6{Addr: addr, Port: port}
+	} else {
+		return newError("ValueError: Invalid socket type %T for bind '%s'", sockaddr, address)
+	}
+
+	if err = syscall.Connect(syscall.Handle(fd), sa); err != nil {
+		return newError("SocketError: %s", err)
+	}
+
+	return &object.Null{}
+}