From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39469) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ctbbi-00024k-Bz for qemu-devel@nongnu.org; Thu, 30 Mar 2017 11:03:27 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ctbbh-0006Qz-A5 for qemu-devel@nongnu.org; Thu, 30 Mar 2017 11:03:26 -0400 From: Markus Armbruster References: <1490879707-6060-1-git-send-email-armbru@redhat.com> <1490879707-6060-8-git-send-email-armbru@redhat.com> Date: Thu, 30 Mar 2017 17:03:12 +0200 In-Reply-To: (Eric Blake's message of "Thu, 30 Mar 2017 09:42:00 -0500") Message-ID: <87inmqzu1b.fsf@dusky.pond.sub.org> MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Qemu-devel] [RFC v2 for-2.9 07/10] sockets: New helper socket_address_crumple() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Eric Blake Cc: qemu-devel@nongnu.org, kwolf@redhat.com, qemu-block@nongnu.org, mitake.hitoshi@lab.ntt.co.jp, jcody@redhat.com, mreitz@redhat.com, pbonzini@redhat.com, namei.unix@gmail.com Eric Blake writes: > On 03/30/2017 08:15 AM, Markus Armbruster wrote: >> SocketAddress is a simple union, and simple unions are awkward: they >> have their variant members wrapped in a "data" object on the wire, and >> require additional indirections in C. I intend to limit its use to >> existing external interfaces. New ones should use SocketAddressFlat. >> I further intend to convert all internal interfaces to >> SocketAddressFlat. This helper should go away then. >> >> Signed-off-by: Markus Armbruster >> --- >> include/qemu/sockets.h | 11 +++++++++++ >> util/qemu-sockets.c | 29 +++++++++++++++++++++++++++++ >> 2 files changed, 40 insertions(+) >> >> diff --git a/include/qemu/sockets.h b/include/qemu/sockets.h >> index 5f1bab9..cef05a5 100644 >> --- a/include/qemu/sockets.h >> +++ b/include/qemu/sockets.h >> @@ -119,4 +119,15 @@ SocketAddress *socket_remote_address(int fd, Error **errp); >> */ >> char *socket_address_to_string(struct SocketAddress *addr, Error **errp); >> >> +/** >> + * socket_address_crumple: >> + * @addr_flat: the socket addres to crumple > > s/addres/address/ Fixing... >> +SocketAddress *socket_address_crumple(SocketAddressFlat *addr_flat) >> +{ >> + SocketAddress *addr = g_new(SocketAddress, 1); >> + >> + addr->type = addr_flat->type; > > Works only because our enum is defined in the same order as the simple > union's members. A bit fragile, so maybe we want to comment in the > .json file that we can't reorder members of either the enum or the > simple union's 'data'? Or it might even tickle a picky compiler to warn > about assignment between incompatible enum types. Another option would > be making it robust by instead doing switch(addr_flat->type) and > assigning to addr->type in each branch of the switch. Sold. >> + switch (addr->type) { >> + case SOCKET_ADDRESS_FLAT_TYPE_INET: >> + addr->u.inet.data = QAPI_CLONE(InetSocketAddress, >> + &addr_flat->u.inet); > > Indentation is off. >> + break; >> + case SOCKET_ADDRESS_FLAT_TYPE_UNIX: >> + addr->u.q_unix.data = QAPI_CLONE(UnixSocketAddress, & >> + addr_flat->u.q_unix); > > Why is the unary & split from its argument? Editing accident. >> + break; >> + case SOCKET_ADDRESS_FLAT_TYPE_VSOCK: >> + addr->u.vsock.data = QAPI_CLONE(VsockSocketAddress, >> + &addr_flat->u.vsock); > > More indentation problems. > >> + break; >> + case SOCKET_ADDRESS_FLAT_TYPE_FD: >> + addr->u.fd.data = QAPI_CLONE(String, &addr_flat->u.fd); >> + break; >> + default: >> + abort(); >> + } >> + >> + return addr; >> +} >> Now looks like this: SocketAddress *socket_address_crumple(SocketAddressFlat *addr_flat) { SocketAddress *addr = g_new(SocketAddress, 1); switch (addr_flat->type) { case SOCKET_ADDRESS_FLAT_TYPE_INET: addr->type = SOCKET_ADDRESS_KIND_INET; addr->u.inet.data = QAPI_CLONE(InetSocketAddress, &addr_flat->u.inet); break; case SOCKET_ADDRESS_FLAT_TYPE_UNIX: addr->type = SOCKET_ADDRESS_KIND_UNIX; addr->u.q_unix.data = QAPI_CLONE(UnixSocketAddress, &addr_flat->u.q_unix); break; case SOCKET_ADDRESS_FLAT_TYPE_VSOCK: addr->type = SOCKET_ADDRESS_KIND_VSOCK; addr->u.vsock.data = QAPI_CLONE(VsockSocketAddress, &addr_flat->u.vsock); break; case SOCKET_ADDRESS_FLAT_TYPE_FD: addr->type = SOCKET_ADDRESS_KIND_FD; addr->u.fd.data = QAPI_CLONE(String, &addr_flat->u.fd); break; default: abort(); } return addr; }