.

wcfs/mm.pyx

@@ -39,8 +39,12 @@ cpdef enum:
 #
 # mem start must be page-aligned.
 def incore(const unsigned char[::1] mem not None) -> bytearray:
-    cdef const void *addr = &mem[0]
     cdef size_t size = mem.shape[0]
+    if size == 0:
+        # XXX ok? or pass addr, 0 to mincore?
+        # XXX if size==0 &mem[0] raises out-of-bounds
+        return bytearray()
+    cdef const void *addr = &mem[0]
 
     # size in pages; rounded up
     cdef size_t pgsize = (size + (PAGE_SIZE-1)) // PAGE_SIZE

wcfs/wcfs_test.py

@@ -397,7 +397,7 @@ def test_wcfs():
     t.wcsync()
 
     # f @head
-    f.assertCache([1,1,0,0])
+    f.assertCache([1,1,0,0])    # XXX fails here (.size changed)
     f.assertData ([b'',b'', s1+b'ld', s2], mtime=t.head)
 
     # f @tcommit1
@@ -406,9 +406,6 @@ def test_wcfs():
     f1.assertData ([b'',b'',s])  # XXX + mtime=tcommit1?
 
 
-# TODO pagecache state after loading (via mincore)
-# TODO pagecahce state after .size change
-
 def test_wcfs_invproto():
     # XXX
     pass