[PATCH 10/22] qapi: Convert simple union TransactionAction to flat one

[Markus Armbruster]

Simple unions predate flat unions.  Having both complicates the QAPI
schema language and the QAPI generator.  We haven't been using simple
unions in new code for a long time, because they are less flexible and
somewhat awkward on the wire.

To prepare for their removal, convert simple union TransactionAction
to an equivalent flat one.  Adds some boilerplate to the schema, which
is a bit ugly, but a lot easier to maintain than the simple union
feature.

Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Hanna Reitz <hreitz@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
---
 qapi/transaction.json | 111 +++++++++++++++++++++++++++++++++++++-----
 1 file changed, 99 insertions(+), 12 deletions(-)

diff --git a/qapi/transaction.json b/qapi/transaction.json
index 894258d9e2..d7fc73d7df 100644
--- a/qapi/transaction.json
+++ b/qapi/transaction.json
@@ -38,6 +38,91 @@
 { 'enum': 'ActionCompletionMode',
   'data': [ 'individual', 'grouped' ] }
 
+##
+# @TransactionActionKind:
+#
+# Since: 6.1
+##
+{ 'enum': 'TransactionActionKind',
+  'data': [ 'abort', 'block-dirty-bitmap-add', 'block-dirty-bitmap-remove',
+            'block-dirty-bitmap-clear', 'block-dirty-bitmap-enable',
+            'block-dirty-bitmap-disable', 'block-dirty-bitmap-merge',
+            'blockdev-backup', 'blockdev-snapshot',
+            'blockdev-snapshot-internal-sync', 'blockdev-snapshot-sync',
+            'drive-backup' ] }
+
+##
+# @AbortWrapper:
+#
+# Since: 6.1
+##
+{ 'struct': 'AbortWrapper',
+  'data': { 'data': 'Abort' } }
+
+##
+# @BlockDirtyBitmapAddWrapper:
+#
+# Since: 6.1
+##
+{ 'struct': 'BlockDirtyBitmapAddWrapper',
+  'data': { 'data': 'BlockDirtyBitmapAdd' } }
+
+##
+# @BlockDirtyBitmapWrapper:
+#
+# Since: 6.1
+##
+{ 'struct': 'BlockDirtyBitmapWrapper',
+  'data': { 'data': 'BlockDirtyBitmap' } }
+
+##
+# @BlockDirtyBitmapMergeWrapper:
+#
+# Since: 6.1
+##
+{ 'struct': 'BlockDirtyBitmapMergeWrapper',
+  'data': { 'data': 'BlockDirtyBitmapMerge' } }
+
+##
+# @BlockdevBackupWrapper:
+#
+# Since: 6.1
+##
+{ 'struct': 'BlockdevBackupWrapper',
+  'data': { 'data': 'BlockdevBackup' } }
+
+##
+# @BlockdevSnapshotWrapper:
+#
+# Since: 6.1
+##
+{ 'struct': 'BlockdevSnapshotWrapper',
+  'data': { 'data': 'BlockdevSnapshot' } }
+
+##
+# @BlockdevSnapshotInternalWrapper:
+#
+# Since: 6.1
+##
+{ 'struct': 'BlockdevSnapshotInternalWrapper',
+  'data': { 'data': 'BlockdevSnapshotInternal' } }
+
+##
+# @BlockdevSnapshotSyncWrapper:
+#
+# Since: 6.1
+##
+{ 'struct': 'BlockdevSnapshotSyncWrapper',
+  'data': { 'data': 'BlockdevSnapshotSync' } }
+
+##
+# @DriveBackupWrapper:
+#
+# Since: 6.1
+##
+{ 'struct': 'DriveBackupWrapper',
+  'data': { 'data': 'DriveBackup' } }
+
 ##
 # @TransactionAction:
 #
@@ -60,19 +145,21 @@
 # Since: 1.1
 ##
 { 'union': 'TransactionAction',
+  'base': { 'type': 'TransactionActionKind' },
+  'discriminator': 'type',
   'data': {
-       'abort': 'Abort',
-       'block-dirty-bitmap-add': 'BlockDirtyBitmapAdd',
-       'block-dirty-bitmap-remove': 'BlockDirtyBitmap',
-       'block-dirty-bitmap-clear': 'BlockDirtyBitmap',
-       'block-dirty-bitmap-enable': 'BlockDirtyBitmap',
-       'block-dirty-bitmap-disable': 'BlockDirtyBitmap',
-       'block-dirty-bitmap-merge': 'BlockDirtyBitmapMerge',
-       'blockdev-backup': 'BlockdevBackup',
-       'blockdev-snapshot': 'BlockdevSnapshot',
-       'blockdev-snapshot-internal-sync': 'BlockdevSnapshotInternal',
-       'blockdev-snapshot-sync': 'BlockdevSnapshotSync',
-       'drive-backup': 'DriveBackup'
+       'abort': 'AbortWrapper',
+       'block-dirty-bitmap-add': 'BlockDirtyBitmapAddWrapper',
+       'block-dirty-bitmap-remove': 'BlockDirtyBitmapWrapper',
+       'block-dirty-bitmap-clear': 'BlockDirtyBitmapWrapper',
+       'block-dirty-bitmap-enable': 'BlockDirtyBitmapWrapper',
+       'block-dirty-bitmap-disable': 'BlockDirtyBitmapWrapper',
+       'block-dirty-bitmap-merge': 'BlockDirtyBitmapMergeWrapper',
+       'blockdev-backup': 'BlockdevBackupWrapper',
+       'blockdev-snapshot': 'BlockdevSnapshotWrapper',
+       'blockdev-snapshot-internal-sync': 'BlockdevSnapshotInternalWrapper',
+       'blockdev-snapshot-sync': 'BlockdevSnapshotSyncWrapper',
+       'drive-backup': 'DriveBackupWrapper'
    } }
 
 ##
-- 
2.31.1