[Qemu-devel] [PATCH v9 10/17] nbd: Convert to new qapi union layout

[Eric Blake <eblake@redhat.com>]

We have two issues with our qapi union layout:
1) Even though the QMP wire format spells the tag 'type', the
C code spells it 'kind', requiring some hacks in the generator.
2) The C struct uses an anonymous union, which places all tag
values in the same namespace as all non-variant members. This
leads to spurious collisions if a tag value matches a QMP name.

Make the conversion to the new layout for NBD-related code.

Signed-off-by: Eric Blake <eblake@redhat.com>

---
v9: new patch, but incorporates parts of v5 31/46 and Markus' RFC:
http://lists.gnu.org/archive/html/qemu-devel/2015-10/msg02236.html
---
 qemu-nbd.c          | 16 ++++++++--------
 util/qemu-sockets.c | 42 +++++++++++++++++++++---------------------
 2 files changed, 29 insertions(+), 29 deletions(-)

diff --git a/qemu-nbd.c b/qemu-nbd.c
index 6428c15..449032d 100644
--- a/qemu-nbd.c
+++ b/qemu-nbd.c
@@ -364,17 +364,17 @@ static SocketAddress *nbd_build_socket_address(const char *sockpath,

     saddr = g_new0(SocketAddress, 1);
     if (sockpath) {
-        saddr->kind = SOCKET_ADDRESS_KIND_UNIX;
-        saddr->q_unix = g_new0(UnixSocketAddress, 1);
-        saddr->q_unix->path = g_strdup(sockpath);
+        saddr->type = SOCKET_ADDRESS_KIND_UNIX;
+        saddr->u.q_unix = g_new0(UnixSocketAddress, 1);
+        saddr->u.q_unix->path = g_strdup(sockpath);
     } else {
-        saddr->kind = SOCKET_ADDRESS_KIND_INET;
-        saddr->inet = g_new0(InetSocketAddress, 1);
-        saddr->inet->host = g_strdup(bindto);
+        saddr->type = SOCKET_ADDRESS_KIND_INET;
+        saddr->u.inet = g_new0(InetSocketAddress, 1);
+        saddr->u.inet->host = g_strdup(bindto);
         if (port) {
-            saddr->inet->port = g_strdup(port);
+            saddr->u.inet->port = g_strdup(port);
         } else  {
-            saddr->inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
+            saddr->u.inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT);
         }
     }

diff --git a/util/qemu-sockets.c b/util/qemu-sockets.c
index 2add83a..492d148 100644
--- a/util/qemu-sockets.c
+++ b/util/qemu-sockets.c
@@ -904,23 +904,23 @@ SocketAddress *socket_parse(const char *str, Error **errp)
             error_setg(errp, "invalid Unix socket address");
             goto fail;
         } else {
-            addr->kind = SOCKET_ADDRESS_KIND_UNIX;
-            addr->q_unix = g_new(UnixSocketAddress, 1);
-            addr->q_unix->path = g_strdup(str + 5);
+            addr->type = SOCKET_ADDRESS_KIND_UNIX;
+            addr->u.q_unix = g_new(UnixSocketAddress, 1);
+            addr->u.q_unix->path = g_strdup(str + 5);
         }
     } else if (strstart(str, "fd:", NULL)) {
         if (str[3] == '\0') {
             error_setg(errp, "invalid file descriptor address");
             goto fail;
         } else {
-            addr->kind = SOCKET_ADDRESS_KIND_FD;
-            addr->fd = g_new(String, 1);
-            addr->fd->str = g_strdup(str + 3);
+            addr->type = SOCKET_ADDRESS_KIND_FD;
+            addr->u.fd = g_new(String, 1);
+            addr->u.fd->str = g_strdup(str + 3);
         }
     } else {
-        addr->kind = SOCKET_ADDRESS_KIND_INET;
-        addr->inet = inet_parse(str, errp);
-        if (addr->inet == NULL) {
+        addr->type = SOCKET_ADDRESS_KIND_INET;
+        addr->u.inet = inet_parse(str, errp);
+        if (addr->u.inet == NULL) {
             goto fail;
         }
     }
@@ -938,19 +938,19 @@ int socket_connect(SocketAddress *addr, Error **errp,
     int fd;

     opts = qemu_opts_create(&socket_optslist, NULL, 0, &error_abort);
-    switch (addr->kind) {
+    switch (addr->type) {
     case SOCKET_ADDRESS_KIND_INET:
-        inet_addr_to_opts(opts, addr->inet);
+        inet_addr_to_opts(opts, addr->u.inet);
         fd = inet_connect_opts(opts, errp, callback, opaque);
         break;

     case SOCKET_ADDRESS_KIND_UNIX:
-        qemu_opt_set(opts, "path", addr->q_unix->path, &error_abort);
+        qemu_opt_set(opts, "path", addr->u.q_unix->path, &error_abort);
         fd = unix_connect_opts(opts, errp, callback, opaque);
         break;

     case SOCKET_ADDRESS_KIND_FD:
-        fd = monitor_get_fd(cur_mon, addr->fd->str, errp);
+        fd = monitor_get_fd(cur_mon, addr->u.fd->str, errp);
         if (fd >= 0 && callback) {
             qemu_set_nonblock(fd);
             callback(fd, NULL, opaque);
@@ -970,19 +970,19 @@ int socket_listen(SocketAddress *addr, Error **errp)
     int fd;

     opts = qemu_opts_create(&socket_optslist, NULL, 0, &error_abort);
-    switch (addr->kind) {
+    switch (addr->type) {
     case SOCKET_ADDRESS_KIND_INET:
-        inet_addr_to_opts(opts, addr->inet);
+        inet_addr_to_opts(opts, addr->u.inet);
         fd = inet_listen_opts(opts, 0, errp);
         break;

     case SOCKET_ADDRESS_KIND_UNIX:
-        qemu_opt_set(opts, "path", addr->q_unix->path, &error_abort);
+        qemu_opt_set(opts, "path", addr->u.q_unix->path, &error_abort);
         fd = unix_listen_opts(opts, errp);
         break;

     case SOCKET_ADDRESS_KIND_FD:
-        fd = monitor_get_fd(cur_mon, addr->fd->str, errp);
+        fd = monitor_get_fd(cur_mon, addr->u.fd->str, errp);
         break;

     default:
@@ -998,12 +998,12 @@ int socket_dgram(SocketAddress *remote, SocketAddress *local, Error **errp)
     int fd;

     opts = qemu_opts_create(&socket_optslist, NULL, 0, &error_abort);
-    switch (remote->kind) {
+    switch (remote->type) {
     case SOCKET_ADDRESS_KIND_INET:
-        inet_addr_to_opts(opts, remote->inet);
+        inet_addr_to_opts(opts, remote->u.inet);
         if (local) {
-            qemu_opt_set(opts, "localaddr", local->inet->host, &error_abort);
-            qemu_opt_set(opts, "localport", local->inet->port, &error_abort);
+            qemu_opt_set(opts, "localaddr", local->u.inet->host, &error_abort);
+            qemu_opt_set(opts, "localport", local->u.inet->port, &error_abort);
         }
         fd = inet_dgram_opts(opts, errp);
         break;
-- 
2.4.3