Re: [PATCH 4/7] block/dirty-bitmap: Clean up local variable shadowing

[Kevin Wolf]

Am 19.09.2023 um 07:48 hat Markus Armbruster geschrieben:
> Kevin Wolf <kwolf@redhat.com> writes:
> 
> > Am 31.08.2023 um 15:25 hat Markus Armbruster geschrieben:
> >> Local variables shadowing other local variables or parameters make the
> >> code needlessly hard to understand.  Tracked down with -Wshadow=local.
> >> Clean up: delete inner declarations when they are actually redundant,
> >> else rename variables.
> >> 
> >> Signed-off-by: Markus Armbruster <armbru@redhat.com>
> >> ---
> >>  block/monitor/bitmap-qmp-cmds.c | 2 +-
> >>  block/qcow2-bitmap.c            | 3 +--
> >>  2 files changed, 2 insertions(+), 3 deletions(-)
> >> 
> >> diff --git a/block/monitor/bitmap-qmp-cmds.c 
> >> b/block/monitor/bitmap-qmp-cmds.c
> >> index 55f778f5af..4d018423d8 100644
> >> --- a/block/monitor/bitmap-qmp-cmds.c
> >> +++ b/block/monitor/bitmap-qmp-cmds.c
> >> @@ -276,7 +276,7 @@ BdrvDirtyBitmap *block_dirty_bitmap_merge(const char 
> >> *node, const char *target,
> >>  
> >>      for (lst = bms; lst; lst = lst->next) {
> >>          switch (lst->value->type) {
> >> -            const char *name, *node;
> >> +            const char *name;
> >>          case QTYPE_QSTRING:
> >>              name = lst->value->u.local;
> >>              src = bdrv_find_dirty_bitmap(bs, name);
> >
> > The names in this function are all over the place... A more ambitious
> > patch could rename the parameters to dst_node/dst_bitmap and these
> > variables to src_node/src_bitmap to get some more consistency (both with
> > each other and with the existing src/dst variables).
> 
> What exactly would you like me to consider?  Perhaps:
> 
> * Rename parameter @node to @dst_node
> 
> * Rename which parameter to @dst_bitmap?

Parameter @target to @dst_bitmap (it's the name of a bitmap in
@node/@dst_node)

> * Rename nested local @node to @src_node
> 
> * Rename which local variable to @src_bitmap?

@name to @src_bitmap (it's the name of a bitmap in the local
@node/@src_node)

> * Move nested locals to function scope

I don't really mind either way, but yes, maybe that would be more
conventional.

That you couldn't tell for two of the variables what they actually are
probably supports the argument that they should be renamed. :-)

Kevin