Re: [Qemu-devel] [PATCH] block: Make more block drivers compile-time configurable

[Max Reitz]

On 19.10.18 13:34, Markus Armbruster wrote:
> From: Jeff Cody <address@hidden>
> 
> This adds configure options to control the following block drivers:
> 
> * Bochs
> * Cloop
> * Dmg
> * Qcow (V1)
> * Vdi
> * Vvfat
> * qed
> * parallels
> * sheepdog
> 
> Each of these defaults to being enabled.
> 
> Signed-off-by: Jeff Cody <address@hidden>
> Signed-off-by: Markus Armbruster <address@hidden>
> ---
> 
> Hmm, we got quite a few --enable-BLOCK-DRIVER now.  Perhaps a single
> list-valued option similar --target-list would be better.  Could be
> done on top.
> 
>  block/Makefile.objs | 22 ++++++++---
>  configure           | 91 +++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 107 insertions(+), 6 deletions(-)
> 
> diff --git a/block/Makefile.objs b/block/Makefile.objs
> index c8337bf186..1cad9fc4f1 100644
> --- a/block/Makefile.objs
> +++ b/block/Makefile.objs

[...]

> @@ -45,7 +54,8 @@ gluster.o-libs     := $(GLUSTERFS_LIBS)
>  vxhs.o-libs        := $(VXHS_LIBS)
>  ssh.o-cflags       := $(LIBSSH2_CFLAGS)
>  ssh.o-libs         := $(LIBSSH2_LIBS)
> -block-obj-$(if $(CONFIG_BZIP2),m,n) += dmg-bz2.o
> +block-obj-dmg-bz2$(if $(CONFIG_BZIP2),m,n) += dmg-bz2.o
> +block-obj-$(CONFIG_DMG) += $(block-obj-dmg-bz2-y)

This defines "block-obj-dmg-bz2m" or "block-obj-dmg-bz2n", so
"block-obj-dmg-bz2-y" is never defined (note both the missing hyphen and
the "m" vs. "y").

How about:

block-obj-dmg-bz2-$(CONFIG_BZIP2) += dmg-bz2.o
block-obj-$(if $(CONFIG_DMG),m,n) += $(block-obj-dmg-bz2-y)

Bonus point: The "+=" are naturally aligned!

(Fun fact on the side: I tried downloading some dmg image, but qemu
refused to open that.  ("sector count 409600 for chunk 4 is larger than
max (131072)" -- yeah, yeah, I know that I'm not the largest guy) -- but
you can test it just by replacing "dmg-bz2.o" by "does-not-exist.o", and
then make complains normally, but stops complaining with --disable-dmg
or --disable-bzip2.)

Max

>  dmg-bz2.o-libs     := $(BZIP2_LIBS)
>  qcow.o-libs        := -lz
>  linux-aio.o-libs   := -laio

signature.asc
Description: OpenPGP digital signature