Re: [Qemu-devel] [PATCH] Add ability to build without any targets enabled

[Peter Maydell]

On 31 August 2012 18:06, Daniel P. Berrange <address@hidden> wrote:
> From: "Daniel P. Berrange" <address@hidden>
>
> The qemu-img, qemu-nbd and qemu-io tools are quite useful in their
> own right. eg LXC can use qemu-img and qemu-nbd to support running
> of containers with qcow2 images. As such it is reasonable to allow
> building these tools, without enabling any QEMU targets. This change
> does two things:
>
>  - Allows passing an empty string to the --target-list arg
>    to disable all targets
>  - Adds --enable-tools/--disable-tools args to enable/disable
>    building of qemu-img, qemu-nbd and qemu-io independantly
>    of whether any softmmu target is disabled. The builds
>    default to enabled at all times.

Feels to me like these should be separate patches.

> With this you can do
>
>   ./configure --target-list=
>
> and get a build that only includes the basic tools
>
> Signed-off-by: Daniel P. Berrange <address@hidden>
> ---
>  configure | 38 ++++++++++++++++++++++++++------------
>  1 file changed, 26 insertions(+), 12 deletions(-)
>
> diff --git a/configure b/configure
> index d97fd81..bbde154 100755
> --- a/configure
> +++ b/configure
> @@ -128,6 +128,7 @@ libs_qga=""
>  debug_info="yes"
>
>  target_list=""
> +without_targets=0
>
>  # Default value for a variable defining feature "foo".
>  #  * foo="no"  feature will only be used if --enable-foo arg is given
> @@ -216,6 +217,7 @@ usb_redir=""
>  opengl=""
>  zlib="yes"
>  guest_agent="yes"
> +want_tools="yes"
>  libiscsi=""
>  coroutine=""
>  seccomp=""
> @@ -614,7 +616,12 @@ for opt do
>    ;;
>    --cpu=*)
>    ;;
> -  --target-list=*) target_list="$optarg"
> +  --target-list=*)
> +    if test -z "$optarg" ; then
> +        without_targets=1
> +    else
> +        target_list="$optarg"
> +    fi
>    ;;

I think the code ends up a bit simpler if you start with
target_list=DEFAULT
and use that as the indicator of 'use default list' rather
than the empty string. However that does add the 'undocumented
feature' that '--target-list=DEFAULT' becomes valid...

-- PMM