pack-objects: fix thinko in revalidate code

diff --git a/git-repack.sh b/git-repack.sh
index eb75c8cda95dabe190cfe9ddba0c6bd7072615f2..584a7323acd79e4092910ec4415f51603eccea61 100755 (executable)
--- a/git-repack.sh
+++ b/git-repack.sh
@@ -38,12 +38,14 @@ case ",$all_into_one," in
        pack_objects=
 
        # Redundancy check in all-into-one case is trivial.
-       existing=`cd "$PACKDIR" && \
+       existing=`test -d "$PACKDIR" && cd "$PACKDIR" && \
            find . -type f \( -name '*.pack' -o -name '*.idx' \) -print`
        ;;
 esac
 pack_objects="$pack_objects $local $quiet $no_reuse_delta$extra"
-name=$(git-rev-list --objects --all $rev_list 2>&1 |
+name=$( { git-rev-list --objects --all $rev_list ||
+         echo "git-rev-list died with exit code $?"
+       } |
        git-pack-objects --non-empty $pack_objects .tmp-pack) ||
        exit 1
 if [ -z "$name" ]; then
@@ -54,9 +56,24 @@ else
        fi
        mkdir -p "$PACKDIR" || exit
 
-       mv .tmp-pack-$name.pack "$PACKDIR/pack-$name.pack" &&
-       mv .tmp-pack-$name.idx  "$PACKDIR/pack-$name.idx" ||
-       exit
+       for sfx in pack idx
+       do
+               if test -f "$PACKDIR/pack-$name.$sfx"
+               then
+                       mv -f "$PACKDIR/pack-$name.$sfx" \
+                               "$PACKDIR/old-pack-$name.$sfx"
+               fi
+       done &&
+       mv -f .tmp-pack-$name.pack "$PACKDIR/pack-$name.pack" &&
+       mv -f .tmp-pack-$name.idx  "$PACKDIR/pack-$name.idx" &&
+       test -f "$PACKDIR/pack-$name.pack" &&
+       test -f "$PACKDIR/pack-$name.idx" || {
+               echo >&2 "Couldn't replace the existing pack with updated one."
+               echo >&2 "The original set of packs have been saved as"
+               echo >&2 "old-pack-$name.{pack,idx} in $PACKDIR."
+               exit 1
+       }
+       rm -f "$PACKDIR/old-pack-$name.pack" "$PACKDIR/old-pack-$name.idx"
 fi
 
 if test "$remove_redundant" = t