diff options
author | Max Reitz <mreitz@redhat.com> | 2018-02-24 16:40:28 +0100 |
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committer | Eric Blake <eblake@redhat.com> | 2018-03-19 14:49:04 -0500 |
commit | 1a56b1e2ab5e9d6d89386ca953b4afb419e15abe (patch) | |
tree | 63b90fb88991f9bfa449be1c7d0b4385ea7c834b /qom | |
parent | 9139b5672360aaa263da1d96cdfdbe16accb6e3b (diff) |
qapi: Add qobject_to()
This is a dynamic casting macro that, given a QObject type, returns an
object as that type or NULL if the object is of a different type (or
NULL itself).
The macro uses lower-case letters because:
1. There does not seem to be a hard rule on whether qemu macros have to
be upper-cased,
2. The current situation in qapi/qmp is inconsistent (compare e.g.
QINCREF() vs. qdict_put()),
3. qobject_to() will evaluate its @obj parameter only once, thus it is
generally not important to the caller whether it is a macro or not,
4. I prefer it aesthetically.
The macro parameter order is chosen with typename first for
consistency with other QAPI macros like QAPI_CLONE(), as well as
for legibility (read it as "qobject to" type "applied to" obj).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20180224154033.29559-3-mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
[eblake: swap parameter order to list type first, avoid clang ubsan
warning on QOBJECT(NULL) and container_of(NULL,type,base)]
Signed-off-by: Eric Blake <eblake@redhat.com>
Diffstat (limited to 'qom')
0 files changed, 0 insertions, 0 deletions