MFC r298311,r298312:

MFC r298311,r298312:

r298311:

Make sure fmemopen succeeds in :test_append_binary_pos before calling ftell
on the FILE object

This fixes potential null pointer dereferences on failure

CID: 1254952

r298312:

Fix double fclose of `fp1` when freopen fails

freopen handles closing file descriptors on error, with the exception of
fdopen'ed descriptors, so closing an already fclose'd file descriptor is
incorrect

CID: 1338525

git-svn-id: svn://svn.freebsd.org/base/stable/10@299021 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f