Document BIO_{get,set}_conn_ip_family macros.

Add BIO_get_conn_ip_family and BIO_set_conn_ip_family macros to
util/private.num and document them in BIO_s_connect.pod.
Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NBen Kaduk <kaduk@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/5007)

doc/man3/BIO_s_connect.pod

@@ -4,8 +4,8 @@
 
 BIO_set_conn_address, BIO_get_conn_address,
 BIO_s_connect, BIO_new_connect, BIO_set_conn_hostname, BIO_set_conn_port,
-BIO_get_conn_hostname,
-BIO_get_conn_port,
+BIO_set_conn_ip_family, BIO_get_conn_ip_family,
+BIO_get_conn_hostname, BIO_get_conn_port,
 BIO_set_nbio, BIO_do_connect - connect BIO
 
 =head1 SYNOPSIS
@@ -19,9 +19,11 @@ BIO_set_nbio, BIO_do_connect - connect BIO
  long BIO_set_conn_hostname(BIO *b, char *name);
  long BIO_set_conn_port(BIO *b, char *port);
  long BIO_set_conn_address(BIO *b, BIO_ADDR *addr);
+ long BIO_set_conn_ip_family(BIO *b, long family);
  const char *BIO_get_conn_hostname(BIO *b);
  const char *BIO_get_conn_port(BIO *b);
  const BIO_ADDR *BIO_get_conn_address(BIO *b);
+ const long BIO_get_conn_ip_family(BIO *b);
 
  long BIO_set_nbio(BIO *b, long n);
 
@@ -69,6 +71,8 @@ list is http, telnet, socks, https, ssl, ftp, and gopher.
 BIO_set_conn_address() sets the address and port information using
 a BIO_ADDR(3ssl).
 
+BIO_set_conn_ip_family() sets the IP family.
+
 BIO_get_conn_hostname() returns the hostname of the connect BIO or
 NULL if the BIO is initialized but no hostname is set.
 This return value is an internal pointer which should not be modified.
@@ -79,6 +83,8 @@ This return value is an internal pointer which should not be modified.
 BIO_get_conn_address() returns the address information as a BIO_ADDR.
 This return value is an internal pointer which should not be modified.
 
+BIO_get_conn_ip_family() returns the IP family of the connect BIO.
+
 BIO_set_nbio() sets the non blocking I/O flag to B<n>. If B<n> is
 zero then blocking I/O is set. If B<n> is 1 then non blocking I/O
 is set. Blocking I/O is the default. The call to BIO_set_nbio()
@@ -126,6 +132,7 @@ the underlying socket has connected and retry the call.
 
 BIO_set_conn_hostname(), BIO_set_conn_port(), BIO_get_conn_hostname(),
 BIO_set_conn_address(), BIO_get_conn_port(), BIO_get_conn_address(),
+BIO_set_conn_ip_family(), BIO_get_conn_ip_family(),
 BIO_set_nbio(), and BIO_do_connect() are macros.
 
 =head1 RETURN VALUES
@@ -135,7 +142,8 @@ BIO_s_connect() returns the connect BIO method.
 BIO_get_fd() returns the socket or -1 if the BIO has not
 been initialized.
 
-BIO_set_conn_address() and BIO_set_conn_port() always return 1.
+BIO_set_conn_address(), BIO_set_conn_port(), and BIO_set_conn_ip_family()
+always return 1.
 
 BIO_set_conn_hostname() returns 1 on success and 0 on failure.
 
@@ -145,6 +153,8 @@ was set.
 BIO_get_conn_hostname() returns the connected hostname or NULL if
 none was set.
 
+BIO_get_conn_ip_family() returns the address family or -1 if none was set.
+
 BIO_get_conn_port() returns a string representing the connected
 port or NULL if not set.
 

util/private.num

@@ -93,6 +93,7 @@ BIO_get_close                           define
 BIO_get_conn_address                    define
 BIO_get_conn_hostname                   define
 BIO_get_conn_port                       define
+BIO_get_conn_ip_family                  define
 BIO_get_fd                              define
 BIO_get_fp                              define
 BIO_get_info_callback                   define
@@ -122,6 +123,7 @@ BIO_set_close                           define
 BIO_set_conn_address                    define
 BIO_set_conn_hostname                   define
 BIO_set_conn_port                       define
+BIO_set_conn_ip_family                  define
 BIO_set_fd                              define
 BIO_set_fp                              define
 BIO_set_info_callback                   define