Prevent negative numbers in dbinfo output.

This might occur if things change while we're calculating the sizes.

Makefile

@@ -1,5 +1,5 @@
 # By default, run the tests.
-all: fscktest
+all: test
 
 version:
 	python setup.py version
@@ -23,10 +23,6 @@ docs:
 lint:
 	pylint --rcfile=.pylintrc nilmdb
 
-fscktest:
-	python -c "import nilmdb.fsck; nilmdb.fsck.Fsck('/home/jim/wsgi/db').check()"
-#	python -c "import nilmdb.fsck; nilmdb.fsck.Fsck('/home/jim/mnt/bucket/mnt/sharon/data/db', True).check()"
-
 test:
 ifeq ($(INSIDE_EMACS), t)
 # Use the slightly more flexible script

nilmdb/server/server.py

@@ -74,8 +74,8 @@ class Root(NilmApp):
         dbsize = nilmdb.utils.du(path)
         return { "path": path,
                  "size": dbsize,
-                 "other": usage.used - dbsize,
-                 "reserved": usage.total - usage.used - usage.free,
+                 "other": max(usage.used - dbsize, 0),
+                 "reserved": max(usage.total - usage.used - usage.free, 0),
                  "free": usage.free }
 
 class Stream(NilmApp):

nilmdb/utils/diskusage.py

@@ -21,7 +21,8 @@ def du(path):
     errors that might occur if we encounter broken symlinks or
     files in the process of being removed."""
     try:
-        size = os.path.getsize(path)
+        st = os.stat(path)
+        size = st.st_blocks * 512
         if os.path.isdir(path):
             for thisfile in os.listdir(path):
                 filepath = os.path.join(path, thisfile)