Greatly simplify error handling in shell scripts

Instead of having detailed error messages, run most
commands through a function that calls err() under
fault conditions.

Where detail is still required, err() is still called
manually. Where it isn't, the error message is simply
whatever command was executed to cause the error.

This results in a massive sloccount reduction for lbmk;
specifically, 178 sloc reduction, or a 8.1% reduction.
The total sloccount is now 2022, for shell scripts.

Signed-off-by: Leah Rowe <leah@libreboot.org>

1 files changed, 19 insertions, 31 deletions

diff --git a/script/update/project/trees b/script/update/project/trees
index 1214ab21..d5d631b6 100755
--- a/script/update/project/trees
+++ b/script/update/project/trees
@@ -15,7 +15,7 @@ eval "$(setvars "" _target tree rev project cfgsdir)"
 
 main()
 {
-	rm -f "${cfgsdir}"/*/seen || err_rm_seen "main 1"
+	x_ rm -f "${cfgsdir}"/*/seen
 
 	printf "Downloading %s and (if available) applying patches\n" \
 	    ${project}
@@ -32,11 +32,10 @@ main()
 	    err "No targets available for project: ${project}"
 
 	for x in ${targets}; do
-		rm -f "${cfgsdir}"/*/seen || err_rm_seen "main 2"
-		download_for_target "${x}" || \
-		    err "${project}/${target}: cannot download source tree"
+		x_ rm -f "${cfgsdir}"/*/seen
+		x_ download_for_target "${x}"
 	done
-	rm -f "${cfgsdir}"/*/seen || err_rm_seen "main 3"
+	x_ rm -f "${cfgsdir}"/*/seen
 }
 
 download_for_target()
@@ -45,10 +44,8 @@ download_for_target()
 	tree="undefined"
 	rev="undefined"
 
-	fetch_config "${_target}" || \
-	    err "download_for_target: ${project}/${_target}: bad target.cfg"
-
-	rm -f "${cfgsdir}"/*/seen || err_rm_seen "download_for_target"
+	x_ fetch_config "${_target}"
+	x_ rm -f "${cfgsdir}"/*/seen
 
 	if [ -d "${project}/${tree}" ]; then
 		printf "REMARK: download/%s %s: exists. Skipping.\n" \
@@ -60,8 +57,7 @@ download_for_target()
 
 	fetch_from_upstream || \
 	    err "download_for_target: cannot fetch: ${project}"
-	prepare_new_tree "${_target}" "${tree}" "${rev}" || \
-	    err "download_for_target: cannot create tree: ${project}/${tree}"
+	x_ prepare_new_tree "${_target}" "${tree}" "${rev}"
 }
 
 fetch_config()
@@ -82,14 +78,16 @@ fetch_config()
 			_target="${tree}"
 			continue
 		elif [ "${tree}" = "undefined" ]; then
-			printf "ERROR (fetch_config): download/%s:" 1>&2
+			printf "ERROR (fetch_config): download/%s:" \
+			    "${project}" 1>&2
 			printf " tree name undefined for '%s\n'" \
-			    "${project}" "${_target}" 1>&2
+			    "${_target}" 1>&2
 			return 1
 		elif [ "${rev}" = "undefined" ]; then
-			printf "ERROR (fetch_config): download/%s:" 1>&2
+			printf "ERROR (fetch_config): download/%s:" \
+			    "${project}" 1>&2
 			printf " commit ID undefined for '%s'\n" \
-			    "${project}" "${_target}" 1>&2
+			    "${_target}" 1>&2
 			return 1
 		else
 			break
@@ -114,8 +112,7 @@ check_config_for_target()
 		    1>&2
 		return 1
 	fi
-	touch "${cfgsdir}/${_target}/seen" || \
-	    err "${project}/${_target}: touch \"${cfgsdir}/${_target}/seen\""
+	x_ touch "${cfgsdir}/${_target}/seen"
 }
 
 fetch_from_upstream()
@@ -137,26 +134,17 @@ prepare_new_tree()
 	[ "${tree}" != "${target}" ] && \
 		printf "(for target, %s)\n" "${target}"
 
-	cp -R "${project}/${project}" "${project}/${tree}" || \
-	    err "${project}/${tree}: cannot copy source tree"
-	git_reset_rev "${project}/${tree}" "${rev}" "err" || \
-	    err "prepare_new_trees ${project}/${tree}: cannot reset <- ${rev}"
+	x_ cp -R "${project}/${project}" "${project}/${tree}"
+	x_ git_reset_rev "${project}/${tree}" "${rev}" "err"
 
 	(
-	cd "${project}/${tree}" || \
-	    err "prepare_new_tree: !cd \"${project}/${tree}\""
+	x_ cd "${project}/${tree}"
 	git submodule update --init --checkout || \
 	    err "prepare_new_tree ${project}/${tree}: can't update git modules"
 	)
 
-	git_am_patches "${PWD}/${project}/${tree}" \
-	    "${PWD}/${cfgsdir}/${tree}/patches" "err" || \
-	    err "prepare_new_trees ${project}/${tree}: cannot apply patches"
-}
-
-err_rm_seen()
-{
-	err "${1}: ${project}/${target}: cannot rm: \"${cfgsdir}/*/seen\""
+	x_ git_am_patches "${PWD}/${project}/${tree}" \
+	    "${PWD}/${cfgsdir}/${tree}/patches" "err"
 }
 
 main $@