[pacman-dev] [PATCH 1/3] makepkg: refactor archive compression for reusability

[Eli Schwartz]

This allows for more easily extending the list of allowed compression
methods, as it has to be modified in only one place.

Also allow the user to specify their own preferred command + options for
source packages in addition to compiled packages. Currently,
makepkg.conf(5) erroneously claims this is already possible.

Signed-off-by: Eli Schwartz <eschwartz at archlinux.org>
---

I'm not 100% sure how to handle this, perhaps it should encompass
bsdtar/$pkg_file as well?

 scripts/makepkg.sh.in | 57 ++++++++++++++++++++++++++-------------------------
 1 file changed, 29 insertions(+), 28 deletions(-)

diff --git a/scripts/makepkg.sh.in b/scripts/makepkg.sh.in
index 20e9dd7e..a5c216dd 100644
--- a/scripts/makepkg.sh.in
+++ b/scripts/makepkg.sh.in
@@ -698,6 +698,26 @@ list_package_files() {
 	sed -e 's|^\./||' | tr '\n' '\0'
 }

+# Wrapper around many stream compression formats, for use in the middle of a
+# pipeline. A tar archive is passed on stdin and compressed to stdout.
+compress_as() {
+	# $1: final archive filename extension for compression type detection
+
+	local ext="$1"
+
+	case "$ext" in
+		*tar.gz)  ${COMPRESSGZ[@]:-gzip -c -f -n} ;;
+		*tar.bz2) ${COMPRESSBZ2[@]:-bzip2 -c -f} ;;
+		*tar.xz)  ${COMPRESSXZ[@]:-xz -c -z -} ;;
+		*tar.lrz) ${COMPRESSLRZ[@]:-lrzip -q} ;;
+		*tar.lzo) ${COMPRESSLZO[@]:-lzop -q} ;;
+		*tar.Z)   ${COMPRESSZ[@]:-compress -c -f} ;;
+		*tar)     cat ;;
+		*) warning "$(gettext "'%s' is not a valid archive extension.")" \
+			"$ext"; cat ;;
+	esac
+}
+
 create_package() {
 	(( NOARCHIVE )) && return

@@ -748,21 +768,8 @@ create_package() {
 	msg2 "$(gettext "Compressing package...")"
 	# TODO: Maybe this can be set globally for robustness
 	shopt -s -o pipefail
-	# bsdtar's gzip compression always saves the time stamp, making one
-	# archive created using the same command line distinct from another.
-	# Disable bsdtar compression and use gzip -n for now.
 	list_package_files | LANG=C bsdtar -cnf - --null --files-from - |
-	case "$PKGEXT" in
-		*tar.gz)  ${COMPRESSGZ[@]:-gzip -c -f -n} ;;
-		*tar.bz2) ${COMPRESSBZ2[@]:-bzip2 -c -f} ;;
-		*tar.xz)  ${COMPRESSXZ[@]:-xz -c -z -} ;;
-		*tar.lrz) ${COMPRESSLRZ[@]:-lrzip -q} ;;
-		*tar.lzo) ${COMPRESSLZO[@]:-lzop -q} ;;
-		*tar.Z)   ${COMPRESSZ[@]:-compress -c -f} ;;
-		*tar)     cat ;;
-		*) warning "$(gettext "'%s' is not a valid archive extension.")" \
-			"$PKGEXT"; cat ;;
-	esac > "${pkg_file}" || ret=$?
+		compress_as "$PKGEXT" > "${pkg_file}" || ret=$?

 	shopt -u -o pipefail

@@ -843,26 +850,20 @@ create_srcpackage() {
 		done
 	done

-	local TAR_OPT
-	case "$SRCEXT" in
-		*tar.gz)  TAR_OPT="-z" ;;
-		*tar.bz2) TAR_OPT="-j" ;;
-		*tar.xz)  TAR_OPT="-J" ;;
-		*tar.lrz) TAR_OPT="--lrzip" ;;
-		*tar.lzo) TAR_OPT="--lzop" ;;
-		*tar.Z)   TAR_OPT="-Z" ;;
-		*tar)     TAR_OPT=""  ;;
-		*) warning "$(gettext "'%s' is not a valid archive extension.")" \
-		"$SRCEXT" ;;
-	esac
-
 	local fullver=$(get_full_version)
 	local pkg_file="$SRCPKGDEST/${pkgbase}-${fullver}${SRCEXT}"

 	# tar it up
 	msg2 "$(gettext "Compressing source package...")"
 	cd_safe "${srclinks}"
-	if ! LANG=C bsdtar -cL ${TAR_OPT} -f "$pkg_file" ${pkgbase}; then
+
+	# TODO: Maybe this can be set globally for robustness
+	shopt -s -o pipefail
+	LANG=C bsdtar -cLf - ${pkgbase} | compress_as "$SRCEXT" > "${pkg_file}" || ret=$?
+
+	shopt -u -o pipefail
+
+	if (( ret )); then
 		error "$(gettext "Failed to create source package file.")"
 		exit 1 # TODO: error code
 	fi
--
2.14.1