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_REGEX_H_INCLUDED_
#define _NGX_REGEX_H_INCLUDED_


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

#include <pcre.h>


#define NGX_REGEX_NO_MATCHED  PCRE_ERROR_NOMATCH   /* -1 */

#define NGX_REGEX_CASELESS    PCRE_CASELESS


typedef struct {
    pcre        *code;
    pcre_extra  *extra;
} ngx_regex_t;


typedef struct {
    ngx_str_t     pattern;
    ngx_pool_t   *pool;
    ngx_int_t     options;

    ngx_regex_t  *regex;
    int           captures;
    int           named_captures;
    int           name_size;
    u_char       *names;
    ngx_str_t     err;
} ngx_regex_compile_t;


typedef struct {
    ngx_regex_t  *regex;
    u_char       *name;
} ngx_regex_elt_t;


void ngx_regex_init(void);
ngx_int_t ngx_regex_compile(ngx_regex_compile_t *rc);

#define ngx_regex_exec(re, s, captures, size)                                \
    pcre_exec(re->code, re->extra, (const char *) (s)->data, (s)->len, 0, 0, \
              captures, size)
#define ngx_regex_exec_n      "pcre_exec()"

ngx_int_t ngx_regex_exec_array(ngx_array_t *a, ngx_str_t *s, ngx_log_t *log);


#endif /* _NGX_REGEX_H_INCLUDED_ */