On Sun, 2024-02-25 at 22:31 -0800, Robin H. Johnson wrote:
> Allow checking any runtime path for installing ever-larger packages.
> 
> CHECKREQS_DISK_RUNTIME=( /boot:40M /:350M /opt:500M )
> 
> Recent example of large packages:
> 
> gentoo-kernel-bin:
> /     >=350MB/version (in /lib/modules)
> /boot >=40MB/version
> 
> rust-bin:
> /opt  >=450MB/version
> 
> Signed-off-by: Robin H. Johnson <robbat2@gentoo.org>
> ---
>  eclass/check-reqs.eclass | 23 +++++++++++++++++++++++
>  1 file changed, 23 insertions(+)
> 
> diff --git a/eclass/check-reqs.eclass b/eclass/check-reqs.eclass
> index fac2f4553d74..1c59c69489a9 100644
> --- a/eclass/check-reqs.eclass
> +++ b/eclass/check-reqs.eclass
> @@ -30,6 +30,13 @@
>  # # install will need this much space in /var
>  # CHECKREQS_DISK_VAR="1024M"
>  #
> +# # install will need this much space in listed paths.
> +# CHECKREQS_DISK_RUNTIME=(
> +#   /var:1G
> +#   /boot/efi:32M

I'd avoid listing /boot/efi as an example, as /boot is a bit special
and might need special handling in the eclass.  In particular,
on the system here I have EFI mounted at /boot, so there
is no /boot/efi.

A possible generic solution would be to "fall back" from non-existing
locations to a "higher" directory, assuming they would normally be
created as subdirectories.

> +#   /opt/giant-package-with-dedicated-disk:100G
> +# )
> +#
>  # @CODE
>  #
>  # If you don't specify a value for, say, CHECKREQS_MEMORY, then the test is not
> @@ -66,6 +73,11 @@ _CHECK_REQS_ECLASS=1
>  # @DESCRIPTION:
>  # How much space is needed in /var? Eg.: CHECKREQS_DISK_VAR=3000M
>  
> +# @ECLASS_VARIABLE: CHECKREQS_DISK_RUNTIME
> +# @DEFAULT_UNSET
> +# @DESCRIPTION:
> +# How much space is needed in paths? Eg.: CHECKREQS_DISK_RUNTIME=( /:1G /var:5G )
> +
>  # @ECLASS_VARIABLE: CHECKREQS_DONOTHING
>  # @USER_VARIABLE
>  # @DEFAULT_UNSET
> @@ -120,6 +132,7 @@ _check-reqs_prepare() {
>  	debug-print-function ${FUNCNAME} "$@"
>  
>  	if [[ -z ${CHECKREQS_MEMORY} &&
> +			"${#CHECKREQS_DISK_RUNTIME[@]}" -eq 0 &&
>  			-z ${CHECKREQS_DISK_BUILD} &&
>  			-z ${CHECKREQS_DISK_USR} &&
>  			-z ${CHECKREQS_DISK_VAR} ]]; then

Considering all the extra logic discussed in this thread, it might be
reasonable to implicitly convert CHECKREQS_DISK_* into
CHECKREQS_DISK_RUNTIME, so they'd share all the solutions discussed.

So ideally the logic would be something like:

1. Append CHECKREQS_DISK_* into CHECKREQS_DISK_RUNTIME.

2. Replace missing paths with the first parent directory that exists.

3. Replace paths with their respective mount points.

4. Sum the values corresponding to the same mount point.

> @@ -161,6 +174,16 @@ _check-reqs_run() {
>  	fi
>  
>  	if [[ ${MERGE_TYPE} != buildonly ]]; then
> +		if [[ "${#CHECKREQS_DISK_RUNTIME[@]}" -gt 0 ]]; then
> +			for _path_size in "${CHECKREQS_DISK_RUNTIME[@]}"; do
> +				_path=${_path_size/:*}
> +				_size=${_path_size/*:}
> +				_check-reqs_disk \
> +					"${EROOT%/}${_path}" "${_size}"
> +			done
> +			unset _path_size _path _size

Instead of setting them globally, then unsetting, you should use local
variables.

> +		fi
> +
>  		[[ -n ${CHECKREQS_DISK_USR} ]] && \
>  			_check-reqs_disk \
>  				"${EROOT%/}/usr" \

-- 
Best regards,
Michał Górny