Re: [kvm-unit-tests PATCH 09/10] scripts: Implement multiline strings for extra_params

Thomas Huth
2023-10-25T17:51:13Z

On 20/10/2023 16.48, Nina Schoetterl-Glausch wrote:
> Implement a rudimentary form only.
> extra_params can get long when passing a lot of arguments to qemu.
> Multiline strings help with readability of the .cfg file.
> Multiline strings begin and end with """, which must occur on separate
> lines.
>
> For example:
> extra_params = """-cpu max,ctop=on -smp cpus=1,cores=16,maxcpus=128 \
> -append '-drawers 2 -books 2 -sockets 2 -cores 16' \
> -device max-s390x-cpu,core-id=31,drawer-id=0,book-id=0,socket-id=0"""
>
> The command string built with extra_params is eval'ed by the runtime
> script, so the newlines need to be escaped with \.
>
> Signed-off-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
> ---
> scripts/common.bash | 16 ++++++++++++++++
> scripts/runtime.bash | 4 ++--
> 2 files changed, 18 insertions(+), 2 deletions(-)
>
> diff --git a/scripts/common.bash b/scripts/common.bash
> index 7b983f7d..b9413d68 100644
> --- a/scripts/common.bash
> +++ b/scripts/common.bash
> @@ -36,6 +36,22 @@ function for_each_unittest()
> kernel=$TEST_DIR/${BASH_REMATCH[1]}
> elif [[ $line =~ ^smp\ *=\ *(.*)$ ]]; then
> smp=${BASH_REMATCH[1]}
> + elif [[ $line =~ ^extra_params\ *=\ *'"""'(.*)$ ]]; then
> + opts=${BASH_REMATCH[1]}$'\n'
> + while read -r -u $fd; do
> + #escape backslash newline, but not double backslash
> + if [[ $opts =~ [^\\]*(\\*)$'\n'$ ]]; then
> + if (( ${#BASH_REMATCH[1]} % 2 == 1 )); then
> + opts=${opts%\\$'\n'}
> + fi
> + fi
> + if [[ "$REPLY" =~ ^(.*)'"""'[:blank:]*$ ]]; then
> + opts+=${BASH_REMATCH[1]}
> + break
> + else
> + opts+=$REPLY$'\n'
> + fi
> + done

Phew, TIL that there is something like $'\n' in bash ...
Now with that knowledge, the regular expression make sense 8-)

Reviewed-by: Thomas Huth <thuth@redhat.com>