Re: [PATCH v4 2/4] qapi: Add feature flags to commands in qapi

[Markus Armbruster <armbru@redhat.com>]

Markus Armbruster <armbru@redhat.com> writes:

> From: Peter Krempa <pkrempa@redhat.com>
>
> Similarly to features for struct types introduce the feature flags also
> for commands. This will allow notifying management layers of fixes and
> compatible changes in the behaviour of a command which may not be
> detectable any other way.
>
> The changes were heavily inspired by commit 6a8c0b51025.
>
> Signed-off-by: Peter Krempa <pkrempa@redhat.com>
> Reviewed-by: Markus Armbruster <armbru@redhat.com>
> Signed-off-by: Markus Armbruster <armbru@redhat.com>
> ---
>  docs/devel/qapi-code-gen.txt   |  7 ++++---
>  qapi/introspect.json           |  6 +++++-
>  scripts/qapi/commands.py       |  3 ++-
>  scripts/qapi/doc.py            |  3 ++-
>  scripts/qapi/expr.py           | 35 +++++++++++++++++++---------------
>  scripts/qapi/introspect.py     |  7 ++++++-
>  scripts/qapi/schema.py         | 22 +++++++++++++++++----
>  tests/qapi-schema/test-qapi.py |  3 ++-
>  8 files changed, 59 insertions(+), 27 deletions(-)
>
> diff --git a/docs/devel/qapi-code-gen.txt b/docs/devel/qapi-code-gen.txt
> index 64d9e4c6a9..637fa49977 100644
> --- a/docs/devel/qapi-code-gen.txt
> +++ b/docs/devel/qapi-code-gen.txt
> @@ -640,9 +640,10 @@ change in the QMP syntax (usually by allowing values or operations
>  that previously resulted in an error).  QMP clients may still need to
>  know whether the extension is available.
>  
> -For this purpose, a list of features can be specified for a struct type.
> -This is exposed to the client as a list of string, where each string
> -signals that this build of QEMU shows a certain behaviour.
> +For this purpose, a list of features can be specified for a command or
> +struct type.  This is exposed to the client as a list of strings,
> +where each string signals that this build of QEMU shows a certain
> +behaviour.
>  
>  Each member of the 'features' array defines a feature.  It can either
>  be { 'name': STRING, '*if': COND }, or STRING, which is shorthand for

Squashing in missing syntax update:

diff --git a/docs/devel/qapi-code-gen.txt b/docs/devel/qapi-code-gen.txt
index 637fa49977..45c93a43cc 100644
--- a/docs/devel/qapi-code-gen.txt
+++ b/docs/devel/qapi-code-gen.txt
@@ -457,7 +457,8 @@ Syntax:
                 '*gen': false,
                 '*allow-oob': true,
                 '*allow-preconfig': true,
-                '*if': COND }
+                '*if': COND,
+                '*features': FEATURES }
 
 Member 'command' names the command.

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