qapi: Improve documentation of file descriptor socket addresses

SocketAddress branch @fd is documented in enum SocketAddressType,
unlike the other branches.  That's because the branch's type is String
from common.json.

Use a local copy of String, so we can put the documentation in the
usual place.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240205074709.3613229-14-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>

chardev/char-socket.c

@@ -1504,7 +1504,7 @@ static void qemu_chr_parse_socket(QemuOpts *opts, ChardevBackend *backend,
         };
     } else {
         addr->type = SOCKET_ADDRESS_TYPE_FD;
-        addr->u.fd.data = g_new(String, 1);
+        addr->u.fd.data = g_new(FdSocketAddress, 1);
         addr->u.fd.data->str = g_strdup(fd);
     }
     sock->addr = addr;

include/hw/virtio/vhost-vsock-common.h

@@ -11,6 +11,7 @@
 #ifndef QEMU_VHOST_VSOCK_COMMON_H
 #define QEMU_VHOST_VSOCK_COMMON_H
 
+#include "qapi/qapi-types-common.h"
 #include "hw/virtio/virtio.h"
 #include "hw/virtio/vhost.h"
 #include "qom/object.h"

qapi/sockets.json

@@ -5,8 +5,6 @@
 # = Socket data types
 ##
 
-{ 'include': 'common.json' }
-
 ##
 # @NetworkAddressFamily:
 #
@@ -116,6 +114,24 @@
     'cid': 'str',
     'port': 'str' } }
 
+##
+# @FdSocketAddress:
+#
+# A file descriptor name or number.
+#
+# @str: decimal is for file descriptor number, otherwise it's a file
+#     descriptor name.  Named file descriptors are permitted in
+#     monitor commands, in combination with the 'getfd' command.
+#     Decimal file descriptors are permitted at startup or other
+#     contexts where no monitor context is active.
+#
+#
+# Since: 1.2
+##
+{ 'struct': 'FdSocketAddress',
+  'data': {
+    'str': 'str' } }
+
 ##
 # @InetSocketAddressWrapper:
 #
@@ -147,12 +163,14 @@
   'data': { 'data': 'VsockSocketAddress' } }
 
 ##
-# @StringWrapper:
+# @FdSocketAddressWrapper:
+#
+# @data: file descriptor name or number
 #
 # Since: 1.3
 ##
-{ 'struct': 'StringWrapper',
+{ 'struct': 'FdSocketAddressWrapper',
-  'data': { 'data': 'String' } }
+  'data': { 'data': 'FdSocketAddress' } }
 
 ##
 # @SocketAddressLegacy:
@@ -173,7 +191,7 @@
     'inet': 'InetSocketAddressWrapper',
     'unix': 'UnixSocketAddressWrapper',
     'vsock': 'VsockSocketAddressWrapper',
-    'fd': 'StringWrapper' } }
+    'fd': 'FdSocketAddressWrapper' } }
 
 ##
 # @SocketAddressType:
@@ -186,11 +204,7 @@
 #
 # @vsock: VMCI address
 #
-# @fd: decimal is for file descriptor number, otherwise a file
+# @fd: Socket file descriptor
-#     descriptor name.  Named file descriptors are permitted in
-#     monitor commands, in combination with the 'getfd' command.
-#     Decimal file descriptors are permitted at startup or other
-#     contexts where no monitor context is active.
 #
 # Since: 2.9
 ##
@@ -200,7 +214,7 @@
 ##
 # @SocketAddress:
 #
-# Captures the address of a socket, which could also be a named file
+# Captures the address of a socket, which could also be a socket file
 # descriptor
 #
 # @type: Transport type
@@ -213,4 +227,4 @@
   'data': { 'inet': 'InetSocketAddress',
             'unix': 'UnixSocketAddress',
             'vsock': 'VsockSocketAddress',
-            'fd': 'String' } }
+            'fd': 'FdSocketAddress' } }

util/qemu-sockets.c

@@ -1464,7 +1464,8 @@ SocketAddress *socket_address_flatten(SocketAddressLegacy *addr_legacy)
         break;
     case SOCKET_ADDRESS_TYPE_FD:
         addr->type = SOCKET_ADDRESS_TYPE_FD;
-        QAPI_CLONE_MEMBERS(String, &addr->u.fd, addr_legacy->u.fd.data);
+        QAPI_CLONE_MEMBERS(FdSocketAddress, &addr->u.fd,
+                           addr_legacy->u.fd.data);
         break;
     default:
         abort();