git-repack-script: Add option to repack all objects.

This originally came from Frank Sorenson, but with a bit of rework to
allow future enhancements without changing the external interface for
pack pruning part.

With the '-a' option, all objects in the current repository are packed
into a single pack.  When the '-d' option is given at the same time,
existing packs that were made redundant by this round of repacking are
deleted.

Since we currently have only two repacking strategies, one with '-a'
(everything into one) and the other without '-a' (incrementally pack
only the unpacked ones), the '-d' option is meaningful only when used
with '-a'; it removes the packs existed before we did the "everything
into one" repacking.  At least for now.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Acked-by: Frank Sorenson <frank@tuxrocks.com>
(cherry picked from bfed505327e31221d8de796b3af880bad696b149 commit)

git-repack-script

@@ -5,28 +5,63 @@
 
 . git-sh-setup-script || die "Not a git archive"
 	
-no_update_info=
+no_update_info= all_into_one= remove_redundant=
 while case "$#" in 0) break ;; esac
 do
 	case "$1" in
 	-n)	no_update_info=t ;;
+	-a)	all_into_one=t ;;
+	-d)	remove_redandant=t ;;
 	*)	break ;;
 	esac
 	shift
 done
 
 rm -f .tmp-pack-*
-packname=$(git-rev-list --unpacked --objects $(git-rev-parse --all) |
-	git-pack-objects --non-empty --incremental .tmp-pack) ||
+PACKDIR="$GIT_OBJECT_DIRECTORY/pack"
+
+# There will be more repacking strategies to come...
+case ",$all_into_one," in
+,,)
+	rev_list='--unpacked'
+	rev_parse='--all'
+	pack_objects='--incremental'
+	;;
+,t,)
+	rev_list=
+	rev_parse='--all'
+	pack_objects=
+	# This part is a stop-gap until we have proper pack redundancy
+	# checker.
+	existing=`cd "$PACKDIR" && \
+	    find . -type f \( -name '*.pack' -o -name '*.idx' \) -print`
+	;;
+esac
+name=$(git-rev-list --objects $rev_list $(git-rev-parse $rev_parse) |
+	git-pack-objects --non-empty $pack_objects .tmp-pack) ||
 	exit 1
-if [ -z "$packname" ]; then
-	echo Nothing new to pack
+if [ -z "$name" ]; then
+	echo Nothing new to pack.
 	exit 0
 fi
+echo "Pack pack-$name created."
+
+mkdir -p "$PACKDIR" || exit
+
+mv .tmp-pack-$name.pack "$PACKDIR/pack-$name.pack" &&
+mv .tmp-pack-$name.idx  "$PACKDIR/pack-$name.idx" ||
+exit
+
+if test "$remove_redandant" = t
+then
+	# We know $existing are all redandant only when
+	# all-into-one is used.
+	if test "$all_into_one" != '' && test "$existing" != ''
+	then
+		( cd "$PACKDIR" && rm -f $existing )
+	fi
+fi
 
-mkdir -p "$GIT_OBJECT_DIRECTORY/pack" &&
-mv .tmp-pack-$packname.pack "$GIT_OBJECT_DIRECTORY/pack/pack-$packname.pack" &&
-mv .tmp-pack-$packname.idx  "$GIT_OBJECT_DIRECTORY/pack/pack-$packname.idx" &&
 case "$no_update_info" in
 t) : ;;
 *) git-update-server-info ;;