Re: [PATCH v8 09/10] nbd: introduce ERRP_AUTO_PROPAGATE

[Eric Blake <eblake@redhat.com>]

On 3/5/20 11:15 PM, Vladimir Sementsov-Ogievskiy wrote:
> If we want to add some info to errp (by error_prepend() or
> error_append_hint()), we must use the ERRP_AUTO_PROPAGATE macro.
> Otherwise, this info will not be added when errp == &error_fatal
> (the program will exit prior to the error_append_hint() or
> error_prepend() call).  Fix such cases.
> 
> If we want to check error after errp-function call, we need to
> introduce local_err and then propagate it to errp. Instead, use
> ERRP_AUTO_PROPAGATE macro, benefits are:
> 1. No need of explicit error_propagate call
> 2. No need of explicit local_err variable: use errp directly
> 3. ERRP_AUTO_PROPAGATE leaves errp as is if it's not NULL or
>     &error_fatal, this means that we don't break error_abort
>     (we'll abort on error_set, not on error_propagate)
> 
> This commit is generated by command
> 
>      sed -n '/^Network Block Device (NBD)$/,/^$/{s/^F: //p}' \
>          MAINTAINERS | \
>      xargs git ls-files | grep '\.[hc]$' | \
>      xargs spatch \
>          --sp-file scripts/coccinelle/auto-propagated-errp.cocci \
>          --macro-file scripts/cocci-macro-file.h \
>          --in-place --no-show-diff --max-width 80
> 
> Reported-by: Kevin Wolf <kwolf@redhat.com>
> Reported-by: Greg Kurz <groug@kaod.org>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
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