=head1 NAME

nbd_set_uri_allow_tls - set the allowed TLS settings in NBD URIs

=head1 SYNOPSIS

 #include <libnbd.h>

 int nbd_set_uri_allow_tls (
       struct nbd_handle *h, int tls
     );

=head1 DESCRIPTION

Set which TLS settings are allowed to appear in NBD URIs.
The default is to allow either non-TLS or TLS URIs.

The C<tls> parameter can be:

=over 4

=item C<LIBNBD_TLS_DISABLE>

TLS URIs are not permitted, ie. a URI such as C<nbds://...>
will be rejected.

=item C<LIBNBD_TLS_ALLOW>

This is the default.  TLS may be used or not, depending on
whether the URI uses C<nbds> or C<nbd>.

=item C<LIBNBD_TLS_REQUIRE>

TLS URIs are required.  All URIs must use C<nbds>.

=back

=head1 RETURN VALUE

If the call is successful the function returns C<0>.

=head1 ERRORS

On error C<-1> is returned.

Refer to L<libnbd(3)/ERROR HANDLING>
for how to get further details of the error.

The following parameters must not be NULL: C<h>.
For more information see L<libnbd(3)/Non-NULL parameters>.

=head1 HANDLE STATE

nbd_set_uri_allow_tls
can be called when the handle is in the following state:

 ┌─────────────────────────────────────┬─────────────────────────┐
 │ Handle created, before connecting   │ ✅ allowed              │
 │ Connecting                          │ ❌ error                │
 │ Connecting & handshaking (opt_mode) │ ❌ error                │
 │ Connected to the server             │ ❌ error                │
 │ Connection shut down                │ ❌ error                │
 │ Handle dead                         │ ❌ error                │
 └─────────────────────────────────────┴─────────────────────────┘

=head1 VERSION

This function first appeared in libnbd 1.2.

If you need to test if this function is available at compile time
check if the following macro is defined:

 #define LIBNBD_HAVE_NBD_SET_URI_ALLOW_TLS 1

=head1 SEE ALSO

L<nbd_connect_uri(3)>,
L<nbd_create(3)>,
L<nbd_set_uri_allow_transports(3)>,
L<libnbd(3)>.

=head1 AUTHORS

Eric Blake

Richard W.M. Jones

=head1 COPYRIGHT

Copyright Red Hat
