avoid unnecessary #to_io calls

Calling `#to_io' is only necessary when we're handling an argument
from user code where the user could pass a non-IO object.
`#to_io' calls are a waste of time when we create the IO object
ourselves (in `Raindrops::InetDiagSock.new').

This allows us to define the `my_fileno' macro for Ruby 3.1+
users to call the new `rb_io_descriptor' function directly
without an extra C stack frame.  This also allows us to get
rid of nesting CPP directives inside C functions which (IMHO)
improves readability.

Furthermore, any necessary #to_io calls using `rb_convert_type'
can be replaced with `rb_io_get_io' to decrease code size.
`rb_io_get_io' has been in ruby/io.h since Ruby 1.9.2 and
there's no expectation that it'd be deprecated since it only
deals with opaque `VALUE' types.

1 files changed, 2 insertions, 2 deletions

diff --git a/ext/raindrops/linux_inet_diag.c b/ext/raindrops/linux_inet_diag.c
index 2a2360c..e1ae62a 100644
--- a/ext/raindrops/linux_inet_diag.c
+++ b/ext/raindrops/linux_inet_diag.c
@@ -627,8 +627,8 @@ static VALUE tcp_listener_stats(int argc, VALUE *argv, VALUE self)
         args.iov[2].iov_len = OPLEN;
         args.iov[2].iov_base = alloca(page_size);
         args.table = NULL;
-        if (NIL_P(sock))
-                sock = rb_funcall(cIDSock, id_new, 0);
+        sock = NIL_P(sock) ? rb_funcall(cIDSock, id_new, 0)
+                        : rb_io_get_io(sock);
         args.fd = my_fileno(sock);
 
         switch (TYPE(addrs)) {