added FROMBUF_FREE

iob_internal.h

@@ -2,8 +2,10 @@
 #include "array.h"
 
 typedef struct iob_entry {
-  enum { FROMBUF, FROMFILE } type;
+  enum { FROMBUF, FROMBUF_FREE, FROMFILE } type;
   int64 fd;
   const char* buf;
   uint64 offset,n;
 } iob_entry;
+
+int iob_addbuf_internal(io_batch* b,const void* buf,uint64 n,int free);