[gc] do gc anyway. Contributes to MER#1285

Do gc even if there was no tree cleanup, so if backup operation was not
finished (snapshot was not created) but head was reset to the previous snapshot,
unreferenced commits from the old head will be removed.

Signed-off-by: Denis Zalevskiy <denis.zalevskiy@jolla.com>

tools/git-vault-gc

@@ -63,30 +63,59 @@ function gen_cmd {
     cat $cmd_file | gawk -f $src/git-vault-rebase-generate.awk
 }
 
+function git_gc {
+    echo "GC"
+    git prune
+    git gc --aggressive
+    echo "PRUNE+"
+    git prune
+}
+
+function git_clear_reflog {
+    echo "CLEAR REFLOG"
+    git reflog expire --expire=now --all || error "clearing reflog"
+}
+
+function git_rm_dangling_blobs {
+    echo "REMOVING DANGLING BLOBS"
+    for obj in $(git fsck --unreachable master \
+                        | grep '^unreachable blob' \
+                        | sed 's/unreachable blob //'); do
+        for blob in $(git show $obj \
+                             | head -n 1 \
+                             | grep '\.\./\.git/blobs' \
+                             | sed 's:^[./]*\.git/blobs:.git/blobs:'); do
+            echo "Orphan $blob"
+            (test -f $blob && (rm $blob -f || echo "Can't remove $blob")) \
+                || echo "No such blob $blob"
+        done
+    done
+}
+
+function git_prune_all_unreferenced {
+    git_clear_reflog
+    git_rm_dangling_blobs
+    git_gc
+}
+
 if ($dump || $dump_intention); then
     $dump_intention && cat $cmd_file
     $dump && gen_cmd
     exit 0
 fi
 
 if ! grep '^\(old_tag\|skip\)' $cmd_file; then
-    echo "There is no need in gc for the $root"
+    echo "There is no need in tree clean-up for the $root"
     if ! $force; then
+        echo "Just checking for dangling blobs and doing gc"
+        git_prune_all_unreferenced
         exit 0
     fi
-    echo "Forcing gc"
+    echo "Forcing tree clean-up and gc"
 fi
 
 cmd=$(gen_cmd)
 
-function git_gc {
-    echo "GC"
-    git prune
-    git gc --aggressive
-    echo "PRUNE+"
-    git prune
-}
-
 function rollback {
     echo "ROLLBACK"
     git reset --hard
@@ -111,21 +140,6 @@ echo "REPLACE MASTER"
     git branch -m migrated master && \
     git branch -D old-master) || error "replacing master"
 
-echo "CLEAR REFLOG"
-git reflog expire --expire=now --all || error "clearing reflog"
-
-echo "REMOVING DANGLING BLOBS"
-for obj in $(git fsck --unreachable master \
-    | grep '^unreachable blob' \
-    | sed 's/unreachable blob //'); do
-    for blob in $(git show $obj \
-        | head -n 1 \
-        | grep '\.\./\.git/blobs' \
-        | sed 's:^[./]*\.git/blobs:.git/blobs:'); do
-        echo "Orphan $blob"
-        (test -f $blob && (rm $blob -f || echo "Can't remove $blob")) \
-            || echo "No such blob $blob"
-    done
-done
-git_gc
+git_prune_all_unreferenced
+
 echo "OK"