Added proper handling of connection close phases. There are following flags in quic connection: closing - true, when a connection close is initiated, for whatever reason draining - true, when a CC frame is received from peer The following state machine is used for closing: +------------------+ | I/HS/AD | +------------------+ | | | | | V | | immediate close initiated: | | reasons: close by top-level protocol, fatal error | | + sends CC (probably with app-level message) | | + starts close_timer: 3 * PTO (current probe timeout) | | | | | V | | +---------+ - Reply to input with CC (rate-limited) | | | CLOSING | - Close/Reset all streams | | +---------+ | | | | | V V | | receives CC | | | | idle | | timer | | | V | | +----------+ | - MUST NOT send anything (MAY send a single CC) | | DRAINING | | - if not already started, starts close_timer: 3 * PTO | +----------+ | - if not already done, close all streams | | | | | | | close_timer fires | | V V +------------------------+ | CLOSED | - clean up all the resources, drop connection +------------------------+ state completely The ngx_quic_close_connection() function gets an "rc" argument, that signals reason of connection closing: NGX_OK - initiated by application (i.e. http/3), follow state machine NGX_DONE - timedout (while idle or draining) NGX_ERROR - fatal error, destroy connection immediately The PTO calculations are not yet implemented, hardcoded value of 5s is used.

/*
 * 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_ */