[pacman-dev] [PATCH v2 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>
---

v2: refactor into a new libmakepkg library
Fix gitignore

I still prefer compress_as() over compress_to(), unless you'd like this
function to write the file as well, rather than just compress from
stdin -> stdout

 scripts/Makefile.am                    |  1 +
 scripts/libmakepkg/.gitignore          |  6 +----
 scripts/libmakepkg/util/compress.sh.in | 47 ++++++++++++++++++++++++++++++++++
 scripts/makepkg.sh.in                  | 37 +++++++-------------------
 4 files changed, 58 insertions(+), 33 deletions(-)
 create mode 100644 scripts/libmakepkg/util/compress.sh.in

diff --git a/scripts/Makefile.am b/scripts/Makefile.am
index 0a36fc58..3ec652ce 100644
--- a/scripts/Makefile.am
+++ b/scripts/Makefile.am
@@ -96,6 +96,7 @@ LIBMAKEPKG_IN = \
 	libmakepkg/tidy/strip.sh \
 	libmakepkg/tidy/zipman.sh \
 	libmakepkg/util.sh \
+	libmakepkg/util/compress.sh \
 	libmakepkg/util/message.sh \
 	libmakepkg/util/option.sh \
 	libmakepkg/util/parseopts.sh \
diff --git a/scripts/libmakepkg/.gitignore b/scripts/libmakepkg/.gitignore
index ceb7bfc4..cf1426a2 100644
--- a/scripts/libmakepkg/.gitignore
+++ b/scripts/libmakepkg/.gitignore
@@ -10,8 +10,4 @@ srcinfo.sh
 tidy.sh
 tidy/*.sh
 util.sh
-util/message.sh
-util/option.sh
-util/parseopts.sh
-util/pkgbuild.sh
-util/source.sh
+util/*.sh
diff --git a/scripts/libmakepkg/util/compress.sh.in b/scripts/libmakepkg/util/compress.sh.in
new file mode 100644
index 00000000..4e020e7f
--- /dev/null
+++ b/scripts/libmakepkg/util/compress.sh.in
@@ -0,0 +1,47 @@
+#!/bin/bash
+#
+#   compress.sh - functions to compress archives in a uniform manner
+#
+#   Copyright (c) 2017 Pacman Development Team <pacman-dev at archlinux.org>
+#
+#   This program is free software; you can redistribute it and/or modify
+#   it under the terms of the GNU General Public License as published by
+#   the Free Software Foundation; either version 2 of the License, or
+#   (at your option) any later version.
+#
+#   This program is distributed in the hope that it will be useful,
+#   but WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#   GNU General Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License
+#   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+[[ -n "$LIBMAKEPKG_UTIL_COMPRESS_SH" ]] && return
+LIBMAKEPKG_UTIL_COMPRESS_SH=1
+
+LIBRARY=${LIBRARY:-'@libmakepkgdir@'}
+
+source "$LIBRARY/util/message.sh"
+
+
+# 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 filename="$1"
+
+	case "$filename" 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.")" \
+			"$ext"; cat ;;
+	esac
+}
diff --git a/scripts/makepkg.sh.in b/scripts/makepkg.sh.in
index fdc8bb6a..6449accd 100644
--- a/scripts/makepkg.sh.in
+++ b/scripts/makepkg.sh.in
@@ -754,21 +754,8 @@ create_package() {
 	msg2 "$(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
 
@@ -849,26 +836,20 @@ 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
-- 
2.14.2