#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       *free;
    ngx_chain_t       *busy;
    
    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           cacheable: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;
    ssize_t            busy_size;
    off_t              read_length;
    off_t              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;
    size_t             limit_rate;
    time_t             start_sec;
    ngx_temp_file_t   *temp_file;
     int     num;
};
ngx_int_t ngx_event_pipe(ngx_event_pipe_t *p, ngx_int_t do_write);
ngx_int_t ngx_event_pipe_copy_input_filter(ngx_event_pipe_t *p, ngx_buf_t *buf);
ngx_int_t ngx_event_pipe_add_free_buf(ngx_event_pipe_t *p, ngx_buf_t *b);
#endif