new file mode 100644
--- /dev/null
+++ b/src/event/ngx_event_pipe.h
@@ -0,0 +1,93 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ */
+
+
+#ifndef _NGX_EVENT_PIPE_H_INCLUDED_
+#define _NGX_EVENT_PIPE_H_INCLUDED_
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_event.h>
+
+
+typedef struct ngx_event_pipe_s  ngx_event_pipe_t;
+
+typedef ngx_int_t (*ngx_event_pipe_input_filter_pt)(ngx_event_pipe_t *p,
+                                                    ngx_buf_t *buf);
+typedef ngx_int_t (*ngx_event_pipe_output_filter_pt)(void *data,
+                                                     ngx_chain_t *chain);
+
+
+struct ngx_event_pipe_s {
+    ngx_connection_t  *upstream;
+    ngx_connection_t  *downstream;
+
+    ngx_chain_t       *free_raw_bufs;
+    ngx_chain_t       *in;
+    ngx_chain_t      **last_in;
+
+    ngx_chain_t       *out;
+    ngx_chain_t      **last_out;
+
+    ngx_chain_t       *free;
+    ngx_chain_t       *busy;
+
+    /*
+     * the input filter i.e. that moves HTTP/1.1 chunks
+     * from the raw bufs to an incoming chain
+     */
+
+    ngx_event_pipe_input_filter_pt    input_filter;
+    void                             *input_ctx;
+
+    ngx_event_pipe_output_filter_pt   output_filter;
+    void                             *output_ctx;
+
+    unsigned           read:1;
+    unsigned           cachable:1;
+    unsigned           single_buf:1;
+    unsigned           free_bufs:1;
+    unsigned           upstream_done:1;
+    unsigned           upstream_error:1;
+    unsigned           upstream_eof:1;
+    unsigned           upstream_blocked:1;
+    unsigned           downstream_done:1;
+    unsigned           downstream_error:1;
+    unsigned           cyclic_temp_file:1;
+
+    ngx_int_t          allocated;
+    ngx_bufs_t         bufs;
+    ngx_buf_tag_t      tag;
+
+    size_t             busy_size;
+
+    off_t              read_length;
+
+    off_t              max_temp_file_size;
+    ssize_t            temp_file_write_size;
+
+    ngx_msec_t         read_timeout;
+    ngx_msec_t         send_timeout;
+    ssize_t            send_lowat;
+
+    ngx_pool_t        *pool;
+    ngx_log_t         *log;
+
+    ngx_chain_t       *preread_bufs;
+    size_t             preread_size;
+    ngx_buf_t         *buf_to_file;
+
+    ngx_temp_file_t   *temp_file;
+
+    /* STUB */ int     num;
+};
+
+
+ngx_int_t ngx_event_pipe(ngx_event_pipe_t *p, int do_write);
+ngx_int_t ngx_event_pipe_copy_input_filter(ngx_event_pipe_t *p, ngx_buf_t *buf);
+
+
+#endif /* _NGX_EVENT_PIPE_H_INCLUDED_ */