Fix page_flush, use off_t correctly

libraries/liblmdb/Makefile

@@ -23,7 +23,7 @@ AR	= ar
 W	= -W -Wall -Wno-unused-parameter -Wbad-function-cast -Wuninitialized
 THREADS = -pthread
 OPT = -O2 -g
-XCFLAGS = -DMDB_VL32
+XCFLAGS = -DMDB_VL32 -D_FILE_OFFSET_BITS=64
 CFLAGS	= $(THREADS) $(OPT) $(W) $(XCFLAGS)
 LDLIBS	= # -lntdll # Windows needs ntdll
 SOLIBS	= # -lntdll

libraries/liblmdb/mdb.c

@@ -3410,15 +3410,16 @@ mdb_page_flush(MDB_txn *txn, int keep)
 	MDB_ID2L	dl = txn->mt_u.dirty_list;
 	unsigned	psize = env->me_psize, j;
 	int			i, pagecount = dl[0].mid, rc;
-	size_t		size = 0, pos = 0;
+	size_t		size = 0;
+	off_t		pos = 0;
 	pgno_t		pgno = 0;
 	MDB_page	*dp = NULL;
 #ifdef _WIN32
 	OVERLAPPED	ov;
 #else
 	struct iovec iov[MDB_COMMIT_PAGES];
-	ssize_t		wpos = 0, wsize = 0, wres;
+	ssize_t		wsize = 0, wres;
-	size_t		next_pos = 1; /* impossible pos, so pos != next_pos */
+	off_t		wpos = 0, next_pos = 1; /* impossible pos, so pos != next_pos */
 	int			n = 0;
 #endif