unityofcommand - deduplicate resource files

1 files changed, 59 insertions, 0 deletions

diff --git a/games-strategy/unityofcommand/unityofcommand-104.ebuild b/games-strategy/unityofcommand/unityofcommand-104.ebuild
index b0e9129..1a5266d 100644
--- a/games-strategy/unityofcommand/unityofcommand-104.ebuild
+++ b/games-strategy/unityofcommand/unityofcommand-104.ebuild
@@ -47,6 +47,64 @@ RDEPEND="${LIBDEPEND}"
 MY_PREFIX=${GAMES_PREFIX_OPT}/${P}
 QA_PREBUILT=${MY_PREFIX#/}/bin/\*
 
+# @FUNCTION: dedup
+# @USAGE: <dir to scan>
+# @DESCRIPTION:
+# Replaces duplicate files in <dir to scan> with hardlinks. To avoid hardlinks
+# being broken later on, this should probably be used on a path in ${D} after
+# the normal install procedure in src_install().
+#
+# Duplicates are detected with cksum(1). Newlines are used internally to
+# separate file paths.
+#
+# The following example src_install function runs the default src_install
+# phase function, then deduplicates files installed to /usr/share.
+# @CODE
+#		src_install() {
+#			default
+#			dedup "${D%/}"/usr/share
+#		}
+# @CODE
+#
+# bash, find, cksum, cut, sort, uniq, grep, rm, ln
+# not previously used in eutils: cksum, cut, uniq, ln (all coreutils)
+# uses emktemp, eumask_{push,pop} from eutils
+dedup() {
+	local dir=${1%/}
+	local listfile=$(emktemp)
+
+	einfo "Scanning for duplicated files in ${dir} ..."
+	[[ -d ${dir} ]] || die "${dir} is not a directory"
+
+	# Use a temporary file to simplify using 'cksum' output for 'uniq' input.
+	eumask_push 177
+	find "${dir}" -type f -exec cksum '{}' \+ > "${listfile}" || die
+	eumask_pop
+
+	cut -s -d " " -f "-2" "${listfile}" |
+		sort |
+		uniq -d |
+		while IFS= read -r line; do
+			local orig=
+			grep -e "^${line} " "${listfile}" |
+				cut -s -d ' ' -f 3- |
+				while IFS= read -r file; do
+					if [[ -z "${orig}" ]]; then
+						orig=${file}
+						einfo "Deduplicating copies of ${orig#${dir}} ..."
+						continue
+					else
+						einfo "Hardlinking ${file#${dir}} ..."
+						[[ -f ${orig} ]] || die "${orig} is not a regular file"
+						[[ -f ${file} ]] || die "${file} is not a regular file"
+						rm -f "${file}" || die
+						ln "${orig}" "${file}" || die
+					fi
+				done
+		done
+	rm -f "${listfile}" || die
+}
+
 pkg_nofetch() {
 	elog "Please download ${SRC_URI}"
 	elog "from ${HOMEPAGE} or http://humblebundle.com"
@@ -72,6 +130,7 @@ src_prepare() {
 src_install() {
 	insinto "${MY_PREFIX}"
 	doins -r *
+	dedup "${D%/}${MY_PREFIX}"
 	# Creates fontconfig crap in CWD if writeable, falls back to ~/.fontconfig/
 	games_make_wrapper ${P} bin/uoc "${MY_PREFIX}" "${MY_PREFIX}/bin"
 	prepgamesdirs