[OE-core] [RFC][PATCH 2/2] buildhistory: support generating md5sum of files

[André Draszik]

Hi,

On Sun, 2019-01-06 at 19:13 +0100, Jacob Kroon wrote:
> Introduce 'md5' in BUILDHISTORY_FEATURES and enable it by default
> when doing reproducible builds.
> 
> When enabled this will additionally create:
> 
>   files-in-package-md5.txt
>   files-in-image-md5.txt
>   files-in-sdk-md5.txt
> 
> containing the md5 checksums of regular files.
> 
> Signed-off-by: Jacob Kroon <jacob.kroon at gmail.com>
> ---
>  meta/classes/buildhistory.bbclass | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/meta/classes/buildhistory.bbclass
> b/meta/classes/buildhistory.bbclass
> index 33eb1b00f6..00f0701dec 100644
> --- a/meta/classes/buildhistory.bbclass
> +++ b/meta/classes/buildhistory.bbclass
> @@ -7,7 +7,8 @@
>  # Copyright (C) 2007-2011 Koen Kooi <koen at openembedded.org>
>  #
>  
> -BUILDHISTORY_FEATURES ?= "image package sdk"
> +BUILDHISTORY_FEATURES ?= "image package sdk \
> +  ${@ "md5" if
> bb.utils.to_boolean(d.getVar('BUILD_REPRODUCIBLE_BINARIES')) else ""}"
>  BUILDHISTORY_DIR ?= "${TOPDIR}/buildhistory"
>  BUILDHISTORY_DIR_IMAGE =
> "${BUILDHISTORY_DIR}/images/${MACHINE_ARCH}/${TCLIBC}/${IMAGE_BASENAME}"
>  BUILDHISTORY_DIR_PACKAGE =
> "${BUILDHISTORY_DIR}/packages/${MULTIMACH_TARGET_SYS}/${PN}"
> @@ -526,7 +527,12 @@ buildhistory_list_files() {
>  		eval ${FAKEROOTENV} ${FAKEROOTCMD} $find_cmd
>  	else
>  		eval $find_cmd
> -	fi | sort -k5 | sed 's/ * -> $//' > $2 )
> +	fi | sort -k5 | sed 's/ * -> $//' > $2
> +	if [ "${@bb.utils.contains('BUILDHISTORY_FEATURES', 'md5', '1', '0',
> d)}" = "1" ] ; then
> +		md5filename=$(echo $2 | sed 's/\.txt$/-md5.txt/')
> +		find -type f | xargs -I{} -n1 md5sum {} | sort -k2 >
> $md5filename

Why don't you
  find . -type f -exec md5sum {} + | sort -sk2 > $md5filename
?
It'll be quite a bit faster because way fewer processes will be spawned.

Am I missing something?

I don't know what the intended use-case of the md5 files is, but could
sha256 or similar maybe be more appropriate?

Cheers,
Andre'


> +		[ -s $md5filename ] || rm $md5filename # remove result if
> empty
> +	fi )
>  }
>  
>  buildhistory_list_pkg_files() {
> -- 
> 2.11.0
>