HTTP/3: generate more H3_FRAME_UNEXPECTED. As per quic-http-34, these are the cases when this error should be generated: If an endpoint receives a second SETTINGS frame on the control stream, the endpoint MUST respond with a connection error of type H3_FRAME_UNEXPECTED SETTINGS frames MUST NOT be sent on any stream other than the control stream. If an endpoint receives a SETTINGS frame on a different stream, the endpoint MUST respond with a connection error of type H3_FRAME_UNEXPECTED. A client MUST NOT send a PUSH_PROMISE frame. A server MUST treat the receipt of a PUSH_PROMISE frame as a connection error of type H3_FRAME_UNEXPECTED; see Section 8. The MAX_PUSH_ID frame is always sent on the control stream. Receipt of a MAX_PUSH_ID frame on any other stream MUST be treated as a connection error of type H3_FRAME_UNEXPECTED. Receipt of an invalid sequence of frames MUST be treated as a connection error of type H3_FRAME_UNEXPECTED; see Section 8. In particular, a DATA frame before any HEADERS frame, or a HEADERS or DATA frame after the trailing HEADERS frame, is considered invalid. A CANCEL_PUSH frame is sent on the control stream. Receiving a CANCEL_PUSH frame on a stream other than the control stream MUST be treated as a connection error of type H3_FRAME_UNEXPECTED. The GOAWAY frame is always sent on the control stream.

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


#ifndef _NGX_RADIX_TREE_H_INCLUDED_
#define _NGX_RADIX_TREE_H_INCLUDED_


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


#define NGX_RADIX_NO_VALUE   (uintptr_t) -1

typedef struct ngx_radix_node_s  ngx_radix_node_t;

struct ngx_radix_node_s {
    ngx_radix_node_t  *right;
    ngx_radix_node_t  *left;
    ngx_radix_node_t  *parent;
    uintptr_t          value;
};


typedef struct {
    ngx_radix_node_t  *root;
    ngx_pool_t        *pool;
    ngx_radix_node_t  *free;
    char              *start;
    size_t             size;
} ngx_radix_tree_t;


ngx_radix_tree_t *ngx_radix_tree_create(ngx_pool_t *pool,
    ngx_int_t preallocate);

ngx_int_t ngx_radix32tree_insert(ngx_radix_tree_t *tree,
    uint32_t key, uint32_t mask, uintptr_t value);
ngx_int_t ngx_radix32tree_delete(ngx_radix_tree_t *tree,
    uint32_t key, uint32_t mask);
uintptr_t ngx_radix32tree_find(ngx_radix_tree_t *tree, uint32_t key);

#if (NGX_HAVE_INET6)
ngx_int_t ngx_radix128tree_insert(ngx_radix_tree_t *tree,
    u_char *key, u_char *mask, uintptr_t value);
ngx_int_t ngx_radix128tree_delete(ngx_radix_tree_t *tree,
    u_char *key, u_char *mask);
uintptr_t ngx_radix128tree_find(ngx_radix_tree_t *tree, u_char *key);
#endif


#endif /* _NGX_RADIX_TREE_H_INCLUDED_ */