HTTP/3: skip empty request body buffers (ticket #2374). When client DATA frame header and its content come in different QUIC packets, it may happen that only the header is processed by the first ngx_http_v3_request_body_filter() call. In this case an empty request body buffer is added to r->request_body->bufs, which is later reused in a subsequent ngx_http_v3_request_body_filter() call without being removed from the body chain. As a result, rb->request_body->bufs ends up with two copies of the same buffer. The fix is to avoid adding empty request body buffers to r->request_body->bufs.

/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_SHMEM_H_INCLUDED_
#define _NGX_SHMEM_H_INCLUDED_


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


typedef struct {
    u_char      *addr;
    size_t       size;
    ngx_str_t    name;
    ngx_log_t   *log;
    ngx_uint_t   exists;   /* unsigned  exists:1;  */
} ngx_shm_t;


ngx_int_t ngx_shm_alloc(ngx_shm_t *shm);
void ngx_shm_free(ngx_shm_t *shm);


#endif /* _NGX_SHMEM_H_INCLUDED_ */