QUIC: avoid excessive buffer allocations in stream output. Previously, when a few bytes were send to a QUIC stream by the application, a 4K buffer was allocated for these bytes. Then a STREAM frame was created and that entire buffer was used as data for that frame. The frame with the buffer were in use up until the frame was acked by client. Meanwhile, when more bytes were send to the stream, more buffers were allocated and assigned as data to newer STREAM frames. In this scenario most buffer memory is unused. Now the unused part of the stream output buffer is available for further stream output while earlier parts of the buffer are waiting to be acked. This is achieved by splitting the output buffer.

/*
 * Copyright (C) Roman Arutyunyan
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_PROXY_PROTOCOL_H_INCLUDED_
#define _NGX_PROXY_PROTOCOL_H_INCLUDED_


#include <ngx_config.h>
#include <ngx_core.h>


#define NGX_PROXY_PROTOCOL_MAX_HEADER  107


struct ngx_proxy_protocol_s {
    ngx_str_t           src_addr;
    ngx_str_t           dst_addr;
    in_port_t           src_port;
    in_port_t           dst_port;
};


u_char *ngx_proxy_protocol_read(ngx_connection_t *c, u_char *buf,
    u_char *last);
u_char *ngx_proxy_protocol_write(ngx_connection_t *c, u_char *buf,
    u_char *last);


#endif /* _NGX_PROXY_PROTOCOL_H_INCLUDED_ */