From a9d5969f210b1347e45e25487f27ece5551a65fa Mon Sep 17 00:00:00 2001
From: Ricardo Pardini <ricardo@pardini.net>
Date: Wed, 23 Aug 2023 14:02:26 +0200
Subject: [PATCH] `config_post_main`: sanity checks for `RELEASE` (vs `ARCH`)
 and `RELEASE+DESKTOP_ENVIRONMENT` (vs `ARCH`)

- the interactive menus didn't allow interactive users to select invalid combinations...
- ... but if specified directly on cmdline, no checks were done at all.
- introduce `exit_with_target_not_supported_error()`, which is just `exit_with_error` (code 43) but with code 44
  - this way the targets pipeline can just warn instead of break;
  - sometimes it's easier multiplying matrixes and skipping the few that can't be built
---
 lib/functions/logging/traps.sh       | 16 ++++++++
 lib/functions/main/config-prepare.sh | 56 ++++++++++++++++++++++++++++
 2 files changed, 72 insertions(+)

diff --git a/lib/functions/logging/traps.sh b/lib/functions/logging/traps.sh
index e658330792..4fb4097cad 100644
--- a/lib/functions/logging/traps.sh
+++ b/lib/functions/logging/traps.sh
@@ -194,3 +194,19 @@ function exit_with_error() {
 
 	exit 43
 }
+
+# terminate build with a specific error code (44), meaning "target not supported".
+# this is exactly like exit_with_error, but will be handled differently by the build pipeline.
+function exit_with_target_not_supported_error() {
+	# Log the error and exit.
+	# Everything else will be done by shared trap handling, above.
+	local _file="${BASH_SOURCE[1]}"
+	local _function=${FUNCNAME[1]}
+	local _line="${BASH_LINENO[0]}"
+
+	display_alert "target not supported! " "${1} ${2}" "err"
+
+	overlayfs_wrapper "cleanup"
+
+	exit 44
+}
diff --git a/lib/functions/main/config-prepare.sh b/lib/functions/main/config-prepare.sh
index 316468d384..c303e76253 100644
--- a/lib/functions/main/config-prepare.sh
+++ b/lib/functions/main/config-prepare.sh
@@ -274,6 +274,9 @@ function config_post_main() {
 		declare -g ARMBIAN_WILL_BUILD_UBOOT=no
 	fi
 
+	# Do some sanity checks for userspace stuff, if RELEASE/DESKTOP_ENVIRONMENT is set.
+	check_config_userspace_release_and_desktop
+
 	display_alert "Extensions: finish configuration" "extension_finish_config" "debug"
 	call_extension_method "extension_finish_config" <<- 'EXTENSION_FINISH_CONFIG'
 		*allow extensions a last chance at configuration just before it is done*
@@ -299,6 +302,59 @@ function set_distribution_status() {
 	return 0 # due to last stmt above being a shortcircuit conditional
 }
 
+function check_config_userspace_release_and_desktop() {
+	# Do some sanity checks for userspace stuff.
+	# If RELEASE is set, it must be a valid release.
+	# We'll also check that the RELEASE supports the ARCH.
+	# Then we'll do the same for RELEASE+DESKTOP_ENVIRONMENT and the ARCH.
+	if [[ "${RELEASE}" != "" ]]; then
+		declare release_distro_dir="${SRC}/config/distributions/${RELEASE}"
+		declare release_distro_arches_file="${release_distro_dir}/architectures"
+
+		if [[ ! -d "${release_distro_dir}" ]]; then
+			exit_with_target_not_supported_error "RELEASE '${RELEASE}' is not supported; there is no '${release_distro_dir}' directory."
+		fi
+
+		if [[ ! -f "${release_distro_arches_file}" ]]; then
+			exit_with_target_not_supported_error "RELEASE '${RELEASE}' does not have file ${release_distro_arches_file}"
+		fi
+
+		if grep -q "${ARCH}" "${release_distro_arches_file}"; then
+			display_alert "RELEASE '${RELEASE}' supports ARCH '${ARCH}'" "RELEASE=${RELEASE} ARCH=${ARCH}; see ${release_distro_arches_file}" "debug"
+		else
+			exit_with_target_not_supported_error "RELEASE '${RELEASE}' does not support ARCH '${ARCH}'; see ${release_distro_arches_file}"
+		fi
+
+		# Desktop sanity checks, in the same vein.
+		if [[ "${DESKTOP_ENVIRONMENT}" != "" ]]; then
+
+			# If DESKTOP_ENVIRONMENT is set, but BUILD_DESKTOP is not, then we have a problem.
+			if [[ "${BUILD_DESKTOP}" != "yes" ]]; then
+				exit_with_error "DESKTOP_ENVIRONMENT is set, but BUILD_DESKTOP is not ==yes - please fix your parameters."
+			fi
+
+			declare desktop_release_distro_dir="${SRC}/config/desktop/${RELEASE}/environments/${DESKTOP_ENVIRONMENT}"
+			declare desktop_release_distro_arches_file="${release_distro_dir}/architectures"
+
+			if [[ ! -d "${desktop_release_distro_dir}" ]]; then
+				exit_with_target_not_supported_error "RELEASE '${RELEASE}' and Desktop Environment '${DESKTOP_ENVIRONMENT}' combination is not supported; there is no '${desktop_release_distro_dir}' directory."
+			fi
+
+			if [[ ! -f "${desktop_release_distro_arches_file}" ]]; then
+				exit_with_target_not_supported_error "RELEASE '${RELEASE}' and Desktop Environment '${DESKTOP_ENVIRONMENT}' combination is not supported; there is no '${desktop_release_distro_arches_file}' file."
+			fi
+
+			if grep -q "${ARCH}" "${desktop_release_distro_arches_file}"; then
+				display_alert "RELEASE '${RELEASE}' and Desktop Environment '${DESKTOP_ENVIRONMENT}' combination is supported" "RELEASE=${RELEASE} ARCH=${ARCH}; see ${desktop_release_distro_arches_file}" "debug"
+			else
+				exit_with_target_not_supported_error "RELEASE '${RELEASE}' and Desktop Environment '${DESKTOP_ENVIRONMENT}' combination is not supported; see ${desktop_release_distro_arches_file}"
+			fi
+		fi
+	fi
+
+	return 0
+}
+
 # Some utility functions
 function branch2dir() {
 	[[ "${1}" == "head" ]] && echo "HEAD" || echo "${1##*:}"