* Re: [Qemu-devel] [PATCH] qemu-img convert: Deprecate using -n and -o together
2019-08-09 9:11 [Qemu-devel] [PATCH] qemu-img convert: Deprecate using -n and -o together Kevin Wolf
@ 2019-08-09 12:51 ` Max Reitz
2019-08-09 12:52 ` Eric Blake
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Max Reitz @ 2019-08-09 12:51 UTC (permalink / raw)
To: Kevin Wolf, qemu-block; +Cc: qemu-devel
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On 09.08.19 11:11, Kevin Wolf wrote:
> bdrv_create options specified with -o have no effect when skipping image
> creation with -n, so this doesn't make sense. Warn against the misuse
> and deprecate the combination so we can make it a hard error later.
>
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> ---
> qemu-img.c | 5 +++++
> qemu-deprecated.texi | 7 +++++++
> 2 files changed, 12 insertions(+)
Reviewed-by: Max Reitz <mreitz@redhat.com>
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^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [Qemu-devel] [PATCH] qemu-img convert: Deprecate using -n and -o together
2019-08-09 9:11 [Qemu-devel] [PATCH] qemu-img convert: Deprecate using -n and -o together Kevin Wolf
2019-08-09 12:51 ` Max Reitz
@ 2019-08-09 12:52 ` Eric Blake
2019-08-09 23:07 ` [Qemu-devel] [Qemu-block] " Nir Soffer
2019-08-12 18:47 ` John Snow
3 siblings, 0 replies; 5+ messages in thread
From: Eric Blake @ 2019-08-09 12:52 UTC (permalink / raw)
To: Kevin Wolf, qemu-block; +Cc: qemu-devel, mreitz
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On 8/9/19 4:11 AM, Kevin Wolf wrote:
> bdrv_create options specified with -o have no effect when skipping image
> creation with -n, so this doesn't make sense. Warn against the misuse
> and deprecate the combination so we can make it a hard error later.
>
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> ---
> qemu-img.c | 5 +++++
> qemu-deprecated.texi | 7 +++++++
> 2 files changed, 12 insertions(+)
>
> diff --git a/qemu-img.c b/qemu-img.c
> index 79983772de..d9321f6418 100644
> --- a/qemu-img.c
> +++ b/qemu-img.c
> @@ -2231,6 +2231,11 @@ static int img_convert(int argc, char **argv)
> goto fail_getopt;
> }
>
> + if (skip_create && options) {
> + warn_report("-o has no effect when skipping image creation");
> + warn_report("This will become an error in future QEMU versions.");
It looks a bit odd to have two output lines, where one is a phrase and
the other is a full sentence. But I don't have any better ideas how to
represent it, so
Reviewed-by: Eric Blake <eblake@redhat.com>
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3226
Virtualization: qemu.org | libvirt.org
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^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH] qemu-img convert: Deprecate using -n and -o together
2019-08-09 9:11 [Qemu-devel] [PATCH] qemu-img convert: Deprecate using -n and -o together Kevin Wolf
2019-08-09 12:51 ` Max Reitz
2019-08-09 12:52 ` Eric Blake
@ 2019-08-09 23:07 ` Nir Soffer
2019-08-12 18:47 ` John Snow
3 siblings, 0 replies; 5+ messages in thread
From: Nir Soffer @ 2019-08-09 23:07 UTC (permalink / raw)
To: Kevin Wolf; +Cc: QEMU Developers, qemu-block, Max Reitz
On Fri, Aug 9, 2019 at 12:11 PM Kevin Wolf <kwolf@redhat.com> wrote:
> bdrv_create options specified with -o have no effect when skipping image
> creation with -n, so this doesn't make sense. Warn against the misuse
> and deprecate the combination so we can make it a hard error later.
>
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> ---
> qemu-img.c | 5 +++++
> qemu-deprecated.texi | 7 +++++++
> 2 files changed, 12 insertions(+)
>
> diff --git a/qemu-img.c b/qemu-img.c
> index 79983772de..d9321f6418 100644
> --- a/qemu-img.c
> +++ b/qemu-img.c
> @@ -2231,6 +2231,11 @@ static int img_convert(int argc, char **argv)
> goto fail_getopt;
> }
>
> + if (skip_create && options) {
> + warn_report("-o has no effect when skipping image creation");
> + warn_report("This will become an error in future QEMU versions.");
> + }
> +
> s.src_num = argc - optind - 1;
> out_filename = s.src_num >= 1 ? argv[argc - 1] : NULL;
>
> diff --git a/qemu-deprecated.texi b/qemu-deprecated.texi
> index fff07bb2a3..7673d079c5 100644
> --- a/qemu-deprecated.texi
> +++ b/qemu-deprecated.texi
> @@ -305,6 +305,13 @@ to just export the entire image and then mount only
> /dev/nbd0p1 than
> it is to reinvoke @command{qemu-nbd -c /dev/nbd0} limited to just a
> subset of the image.
>
> +@subsection qemu-img convert -n -o (since 4.2.0)
> +
> +All options specified in @option{-o} are image creation options, so they
> +have no effect when used with @option{-n} to skip image creation. This
> +combination never made sense and shows that the user misunderstood the
> +effect of the options, so this will be made an error in future versions.
>
The user misunderstood by not reading qemu code?
Both the online help and the manual page do not mention anything about
that, so I think
they should be fixed to explain the behavior, and this text should mention
that the behavior
was never documented.
Nir
> +
> @section Build system
>
> @subsection Python 2 support (since 4.1.0)
> --
> 2.20.1
>
>
>
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [Qemu-devel] [Qemu-block] [PATCH] qemu-img convert: Deprecate using -n and -o together
2019-08-09 9:11 [Qemu-devel] [PATCH] qemu-img convert: Deprecate using -n and -o together Kevin Wolf
` (2 preceding siblings ...)
2019-08-09 23:07 ` [Qemu-devel] [Qemu-block] " Nir Soffer
@ 2019-08-12 18:47 ` John Snow
3 siblings, 0 replies; 5+ messages in thread
From: John Snow @ 2019-08-12 18:47 UTC (permalink / raw)
To: Kevin Wolf, qemu-block; +Cc: qemu-devel, mreitz
On 8/9/19 5:11 AM, Kevin Wolf wrote:
> bdrv_create options specified with -o have no effect when skipping image
> creation with -n, so this doesn't make sense. Warn against the misuse
> and deprecate the combination so we can make it a hard error later.
>
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> ---
> qemu-img.c | 5 +++++
> qemu-deprecated.texi | 7 +++++++
> 2 files changed, 12 insertions(+)
>
> diff --git a/qemu-img.c b/qemu-img.c
> index 79983772de..d9321f6418 100644
> --- a/qemu-img.c
> +++ b/qemu-img.c
> @@ -2231,6 +2231,11 @@ static int img_convert(int argc, char **argv)
> goto fail_getopt;
> }
>
> + if (skip_create && options) {
> + warn_report("-o has no effect when skipping image creation");
> + warn_report("This will become an error in future QEMU versions.");
> + }
> +
> s.src_num = argc - optind - 1;
> out_filename = s.src_num >= 1 ? argv[argc - 1] : NULL;
>
> diff --git a/qemu-deprecated.texi b/qemu-deprecated.texi
> index fff07bb2a3..7673d079c5 100644
> --- a/qemu-deprecated.texi
> +++ b/qemu-deprecated.texi
> @@ -305,6 +305,13 @@ to just export the entire image and then mount only /dev/nbd0p1 than
> it is to reinvoke @command{qemu-nbd -c /dev/nbd0} limited to just a
> subset of the image.
>
> +@subsection qemu-img convert -n -o (since 4.2.0)
> +
> +All options specified in @option{-o} are image creation options, so they
> +have no effect when used with @option{-n} to skip image creation. This
> +combination never made sense and shows that the user misunderstood the
> +effect of the options, so this will be made an error in future versions.
> +
I would avoid too much finger-wagging here. We can just say that the
combination never had a well-defined behavior, so it will now be treated
as an error.
Otherwise:
Reviewed-by: John Snow <jsnow@redhat.com>
^ permalink raw reply [flat|nested] 5+ messages in thread