/*
 * 模块名称：NET 层事件分发与周期对账（net_events）主机侧单元测试
 * 模块功能：在 PC 上离线验证 Drivers/BSP/NET/net_events.c 的五个事件入口与周期对账器：
 *           对端六元组解析、**陈旧中断防误判**（芯片说还在连接就不许拆会话）、疑似
 *           误报延后交给对账器、超时把会话标成异常释放（喂给 net_pending 收尾报
 *           CONNRESET 的那条输入）、掉线自愈自接，以及对账器的 100ms 周期闸门、
 *           1000ms 冷却、五种不一致形态的稳定计数（死亡要连观 4 次、重开监听 2 次、
 *           自接 1 次）与 U11 的 CLOSED->LISTENING 重同步。
 *
 * 被测对象：真实源文件 ../../../Drivers/BSP/NET/net_events.c（#include 原样纳入）。
 *           net_events.h / net_types.h / net_pending.h / net_listener.h 全用**真实头**
 *           （net_event_cb_t 回调签名、NET_EVENT_* / NET_SOCK_STATE_* /
 *           net_listener_settle_t / NET_LISTENER_REQ_* 一改即编译期报错）。假件：
 *             共享假 CH395F（本批补齐对端六元组与链路变更计数）、可控 socket 表
 *             （net_sock_raw 对未在用槽位也返回项，与真实语义一致）、**可观测的事件
 *             回调**（记 fd / 事件 / arg）、记录型 net_listener_settle/request 与
 *             net_pending_cancel / net_send_pending_cancel、可控时基、dbg_log 计数。
 *
 * 为什么要主机侧单测（而不是只靠台架）：
 *   1. CH395F 的中断是**整体读即清**且单连接 socket 复用同一个号，"迟到的 DISCONNECT"
 *      与"丢了 CONNECT 的已连接"在真机上都会发生，却无法按需复现。误判的代价直接落在
 *      现场设备上：把还活着的会话拆掉（104 主站看到莫名掉线），或让 socket 永远停在
 *      已连接假象里不再重开。
 *   2. 对账器的**稳定计数**（死亡 4 次、重开监听 2 次、自接 1 次）本质是"别拿一次
 *      采样就把连接折腾死"。真机一次采样 100ms，凑够 4 次要 400ms，且必须一路稳定；
 *      台架上没法按毫秒喂，也看不出为什么"偶尔不重开"。主机侧把时基做成显式量后，
 *      第 3 次不该动、第 4 次该动、之后 1000ms 内不许再动，全部可精确断言。
 *   3. handle_timeout_event 会置 released_abnormal=1，而 net_pending 收尾时正是靠
 *      这个标志把挂起 recv 报成 CONNRESET 而不是 0（见 test/host/net_pending 的
 *      TC-NETPEND-014）。两个模块之间这条**跨文件因果**，只有两边都能离线跑时才可测。
 *
 * 覆盖点：TC-NETEV-001..006 CONNECT；010..014 DISCONNECT（含两条陈旧中断防误判）；
 *   020/021 RECV 与 SEND；030..032 TIMEOUT；040..042 掉线自愈；050..058 周期对账
 *   （周期闸门、链路变更留痕、五种不一致形态、稳定计数、冷却、in_use 兜底）。
 *
 * 通过：全部 TC PASS（main 返回 0）。
 * 入口：int main(void)，返回 0=PASS / 1=FAIL（由 run 脚本判读）。
 *
 * 创建日期：2026-10-23
 */

#include <stdio.h>
#include <string.h>

#include "net_events.h"
#include "net_listener.h"
#include "net_pending.h"
#include "net_socket.h"
#include "ch395f.h"

#include "ch395f_fake.c"
#include "net_events.c"

static int s_total;
static int s_passed;
static int s_failed;

#define CHECK(cond, name) do { \
    s_total++; \
    if (cond) { s_passed++; printf("  PASS %s\n", name); } \
    else { s_failed++; printf("  FAIL %s (line %d)\n", name, __LINE__); } \
} while (0)

/* ===================== dbg_log 计数 ===================== */

int g_nev_info_count;
int g_nev_error_count;
int g_nev_debug_count;

/* ===================== 可观测的事件回调 ===================== */

static int      g_ev_n;
static int      g_ev_fd[16];
static int      g_ev_kind[16];
static void    *g_ev_arg[16];
static int      g_ev_token;

static void ev_cb(int sockfd, net_event_t event, void *arg)
{
    if (g_ev_n < (int)(sizeof(g_ev_fd) / sizeof(g_ev_fd[0]))) {
        g_ev_fd[g_ev_n] = sockfd;
        g_ev_kind[g_ev_n] = (int)event;
        g_ev_arg[g_ev_n] = arg;
    }
    g_ev_n++;
}

/* ===================== 记录型监听与挂起取消 ===================== */

static int g_settle_n;
static int g_settle_sock;
static int g_settle_level;
static int g_req_n;
static int g_req_sock;
static int g_req_reason;
static int g_pcan_n;
static int g_scan_n;
static int g_pcan_err;

void net_listener_settle(int sockfd, net_listener_settle_t level)
{
    g_settle_n++;
    g_settle_sock = sockfd;
    g_settle_level = (int)level;
}

void net_listener_request(int sockfd, net_listener_req_t reason)
{
    g_req_n++;
    g_req_sock = sockfd;
    g_req_reason = (int)reason;
}

void net_listener_clear(int sockfd) { (void)sockfd; }
void net_listener_tick(void) { }

void net_pending_cancel(int sockfd, int err)
{
    (void)sockfd;
    g_pcan_n++;
    g_pcan_err = err;
}

void net_send_pending_cancel(int sockfd, int err)
{
    (void)sockfd;
    (void)err;
    g_scan_n++;
}

/* ===================== 可控时基、errno 与 socket 表 ===================== */

static uint32_t g_now;
static int g_errno_last;

uint32_t HAL_GetTick(void) { return g_now; }

int net_set_errno(int err) { g_errno_last = err; return err; }

uint32_t xTaskGetTickCount(void) { return g_now; }

static net_sock_t g_tbl[NET_MAX_SOCKETS];

net_sock_t *net_sock_raw(int sockfd)
{
    if ((sockfd < 0) || (sockfd >= NET_MAX_SOCKETS)) {
        return NULL;
    }
    /* 与真实语义一致：对账循环必须能读到 in_use == 0 的槽位，所以这里不给 NULL */
    return &g_tbl[sockfd];
}

net_sock_t *net_get_sock(int sockfd)
{
    net_sock_t *p = net_sock_raw(sockfd);

    if ((p == NULL) || (p->in_use == 0u)) {
        return NULL;
    }
    return p;
}

static void reset_all(void)
{
    int i;

    (void)memset(g_tbl, 0, sizeof(g_tbl));
    g_now = 1000u;
    g_errno_last = 0;
    g_ev_n = 0;
    g_settle_n = 0;
    g_settle_sock = -1;
    g_settle_level = -1;
    g_req_n = 0;
    g_req_sock = -1;
    g_req_reason = -1;
    g_pcan_n = 0;
    g_scan_n = 0;
    g_pcan_err = 0;
    g_nev_info_count = 0;
    g_nev_error_count = 0;
    g_nev_debug_count = 0;
    ch395f_fake_reset();
    (void)i;
}

/* 一个"带应用回调的在用槽位"，ch395_sock 与数组下标同号 */
static net_sock_t *mk(int fd, net_sock_state_t st, uint16_t local_port)
{
    net_sock_t *p = &g_tbl[fd];

    p->in_use = 1u;
    p->ch395_sock = (uint8_t)fd;
    p->type = NET_SOCK_STREAM;
    p->state = st;
    p->auto_relisten = 1u;
    p->local_port = local_port;
    p->event_cb = ev_cb;
    p->event_arg = (void *)&g_ev_token;
    return p;
}

/* ===================== CONNECT ===================== */

static void tc_connect(void)
{
    net_sock_t *p;

    printf("-- TC-NETEV-001..006 CONNECT --\n");
    reset_all();
    p = mk(0, NET_SOCK_STATE_LISTENING, 2404u);
    ch395f_fake_set_peer(0, 192u, 168u, 1u, 50u, 51234u);
    handle_connect_event(p);
    /* remote_ip 是**低字节在前**拼的（remote[0] 落在最低 8 位），与网络序相反：
     * 192.168.1.50 -> 0x3201A8C0。这是既有实现的字节序，钉住它是防止有人"顺手
     * 改成大端"导致所有按 IP 比对/白名单的判断静默错位。 */
    CHECK((p->remote_ip_arr[0] == 192u) && (p->remote_ip_arr[3] == 50u) &&
          (p->remote_ip == ((192u) | (168u << 8) | (1u << 16) | (50u << 24))) &&
          (p->remote_port == 51234u),
          "TC-NETEV-001 peer tuple parsing: ip assembled little-endian into 32 bits, port from bytes 5/6");
    CHECK((p->state == NET_SOCK_STATE_ESTABLISHED) && (p->session_dead == 0u) &&
          (p->lost_conn_seen == 0u) && (p->send_ready == 1u),
          "TC-NETEV-002 a listened socket becomes established after self-accept and is writable at once");
    CHECK((g_chip.keepalive_calls == 1) && (g_chip.last_keepalive == 1u) &&
          (g_chip.int_status_calls == 1),
          "TC-NETEV-003 on connect, enable keepalive and clear the pending bit once (read clears)");
    CHECK((g_ev_n == 1) && (g_ev_kind[0] == (int)NET_EVENT_CONNECTED) &&
          (g_ev_fd[0] == 0) && (g_ev_arg[0] == (void *)&g_ev_token),
          "TC-NETEV-004 the event calls back into the app with fd and the caller arg");

    reset_all();
    p = mk(0, NET_SOCK_STATE_CONNECTING, 0u);
    ch395f_fake_set_peer(0, 10u, 0u, 0u, 1u, 2404u);
    handle_connect_event(p);
    CHECK((p->state == NET_SOCK_STATE_ESTABLISHED) && (p->send_ready == 0u) &&
          (g_chip.keepalive_calls == 1) && (g_ev_n == 1),
          "TC-NETEV-005 the active-connect branch also becomes established but does NOT touch send_ready (differs from self-accept)");

    reset_all();
    p = mk(0, NET_SOCK_STATE_CLOSED, 2404u);
    handle_connect_event(p);
    CHECK((g_ev_n == 0) && (p->state == NET_SOCK_STATE_CLOSED),
          "TC-NETEV-006 a CONNECT interrupt in any other state is ignored (never invent a session)");
}

/* ===================== DISCONNECT ===================== */

static void tc_disconnect(void)
{
    net_sock_t *p;

    printf("-- TC-NETEV-010..014 DISCONNECT --\n");
    reset_all();
    p = mk(0, NET_SOCK_STATE_ESTABLISHED, 2404u);
    g_fake.status_byte0[0] = CH395F_SOCKET_OPEN;
    g_fake.status_byte1[0] = CH395F_TCP_ESTABLISHED;
    handle_disconnect_event(p);
    CHECK((p->state == NET_SOCK_STATE_ESTABLISHED) && (g_ev_n == 0) &&
          (g_nev_error_count == 1),
          "TC-NETEV-010 the chip still says connecting: ignore this stale DISCONNECT (never tear down a live session)");

    reset_all();
    p = mk(0, NET_SOCK_STATE_ESTABLISHED, 2404u);
    g_fake.status_byte0[0] = CH395F_SOCKET_OPEN;
    g_fake.status_byte1[0] = CH395F_TCP_CLOSED;
    ch395f_fake_push_recv_len(0, 9u);           /* 还有 9 字节没读走 */
    handle_disconnect_event(p);
    CHECK((p->state == NET_SOCK_STATE_ESTABLISHED) && (p->lost_conn_seen == 1u) &&
          (g_ev_n == 0) && (g_settle_n == 0),
          "TC-NETEV-011 suspected false alarm (dropped before any data): defer to the reconciler instead of tearing down");

    reset_all();
    p = mk(0, NET_SOCK_STATE_ESTABLISHED, 2404u);
    p->remote_port = 51234u;
    g_fake.status_byte0[0] = CH395F_SOCKET_OPEN;
    g_fake.status_byte1[0] = CH395F_TCP_CLOSED;
    handle_disconnect_event(p);
    CHECK((g_settle_n == 1) && (g_settle_level == (int)NET_LISTENER_SETTLE_GRACEFUL) &&
          (p->session_dead == 1u) && (p->released_abnormal == 0u) &&
          (p->last_peer_port == 51234u) &&
          (p->state == NET_SOCK_STATE_CLOSED) &&
          (g_ev_kind[0] == (int)NET_EVENT_DISCONNECTED),
          "TC-NETEV-012 normal disconnect: graceful settle + mark session dead + remember old port + post event");

    reset_all();
    p = mk(0, NET_SOCK_STATE_LISTENING, 2404u);
    g_fake.status_byte0[0] = CH395F_SOCKET_OPEN;
    g_fake.status_byte1[0] = CH395F_TCP_LISTEN;
    handle_disconnect_event(p);
    CHECK((p->state == NET_SOCK_STATE_LISTENING) && (g_ev_n == 0) &&
          (g_nev_info_count == 1) && (g_nev_error_count == 0),
          "TC-NETEV-013 listen still alive: a stale listen DISCONNECT is only logged, not reported as ERROR");

    reset_all();
    p = mk(0, NET_SOCK_STATE_LISTENING, 2404u);
    g_fake.status_byte1[0] = CH395F_TCP_CLOSED;   /* 芯片说不在 LISTEN */
    handle_disconnect_event(p);
    CHECK((p->state == NET_SOCK_STATE_LISTENING) && (g_ev_n == 0) && (g_req_n == 0),
          "TC-NETEV-013b even a lost listener is only logged: reopening belongs to the reconciler, the event layer must not overreach");

    reset_all();
    p = mk(0, NET_SOCK_STATE_CONNECTING, 0u);
    handle_disconnect_event(p);
    CHECK((g_nev_error_count == 1) && (g_ev_kind[0] == (int)NET_EVENT_DISCONNECTED),
          "TC-NETEV-014 DISCONNECT in an unusual state: report ERROR but still notify the application");
}

/* ===================== RECV / SEND / TIMEOUT ===================== */

static void tc_recv_send_timeout(void)
{
    net_sock_t *p;

    printf("-- TC-NETEV-020/021/030..032 --\n");
    reset_all();
    p = mk(0, NET_SOCK_STATE_ESTABLISHED, 2404u);
    handle_recv_event(p);
    CHECK((p->readable == 1u) && (g_ev_kind[0] == (int)NET_EVENT_DATA_RECEIVED),
          "TC-NETEV-020 a RECV event sets readable and notifies the application");

    reset_all();
    p = mk(0, NET_SOCK_STATE_ESTABLISHED, 2404u);
    p->send_ready = 1u;
    handle_send_event(p);
    CHECK((g_ev_kind[0] == (int)NET_EVENT_SEND_COMPLETE) && (p->send_ready == 1u),
          "TC-NETEV-021 SEND completion only posts the event; the fields stay owned by the write path");

    reset_all();
    p = mk(0, NET_SOCK_STATE_CONNECTING, 0u);
    handle_timeout_event(p);
    CHECK((p->state == NET_SOCK_STATE_CREATED) && (g_nev_error_count == 1) &&
          (g_ev_kind[0] == (int)NET_EVENT_TIMEOUT),
          "TC-NETEV-030 connect timeout: fall back to CREATED and notify the application");

    reset_all();
    p = mk(0, NET_SOCK_STATE_ESTABLISHED, 2404u);
    p->remote_port = 777u;
    handle_timeout_event(p);
    CHECK((g_settle_level == (int)NET_LISTENER_SETTLE_QUARANTINE) &&
          (p->released_abnormal == 1u) && (p->session_dead == 1u) &&
          (p->last_peer_port == 777u) && (p->state == NET_SOCK_STATE_CLOSED),
          "TC-NETEV-031 session timeout: quarantine-level settle + mark released abnormally (net_pending reports CONNRESET from it)");

    reset_all();
    p = mk(0, NET_SOCK_STATE_LISTENING, 2404u);
    handle_timeout_event(p);
    CHECK((p->state == NET_SOCK_STATE_LISTENING) && (g_nev_error_count == 1) &&
          (g_ev_kind[0] == (int)NET_EVENT_TIMEOUT),
          "TC-NETEV-032 listen timeout is only logged: state unchanged but waiters are still notified");
}

/* ===================== 掉线自愈 ===================== */

static void tc_lost_probe(void)
{
    net_sock_t *p;

    printf("-- TC-NETEV-040..042 lost-CONNECT probe --\n");
    reset_all();
    p = mk(0, NET_SOCK_STATE_CLOSED, 2404u);
    p->lost_conn_seen = 1u;
    g_fake.cached_tcp[0] = CH395F_TCP_CLOSED;
    net_lost_connect_probe(p);
    CHECK((p->lost_conn_seen == 0u) && (g_ev_n == 0),
          "TC-NETEV-040 the chip is not established: only clear the flag, do not create a session on our own");

    reset_all();
    p = mk(0, NET_SOCK_STATE_CLOSED, 2404u);
    p->lost_conn_seen = 1u;
    p->last_peer_port = 51234u;
    g_fake.cached_tcp[0] = CH395F_TCP_ESTABLISHED;
    ch395f_fake_set_peer(0, 10u, 0u, 0u, 9u, 51234u);
    net_lost_connect_probe(p);
    CHECK((p->lost_conn_seen == 0u) && (g_ev_n == 0),
          "TC-NETEV-041 peer port identical to last time: assume we missed CONNECT, do not accept a second time");

    /* 自愈的适用面是软件还写着 LISTENING、芯片其实已经连上——accept 分支只认
     * LISTENING/CONNECTING。若软件态已被别处改成 CLOSED，本函数打完 INFO 后什么都
     * 不会发生（现状留痕，见第二断言）。 */
    reset_all();
    p = mk(0, NET_SOCK_STATE_LISTENING, 2404u);
    p->lost_conn_seen = 1u;
    p->last_peer_port = 1u;
    g_fake.cached_tcp[0] = CH395F_TCP_ESTABLISHED;
    ch395f_fake_set_peer(0, 10u, 0u, 0u, 9u, 55555u);
    net_lost_connect_probe(p);
    CHECK((g_ev_n == 1) && (g_ev_kind[0] == (int)NET_EVENT_CONNECTED) &&
          (p->state == NET_SOCK_STATE_ESTABLISHED) && (p->remote_port == 55555u) &&
          (p->lost_conn_seen == 0u),
          "TC-NETEV-042 self-heal after a lost CONNECT interrupt: make up one accept so the session is not stranded forever");

    reset_all();
    p = mk(0, NET_SOCK_STATE_CLOSED, 2404u);
    g_fake.cached_tcp[0] = CH395F_TCP_ESTABLISHED;
    ch395f_fake_set_peer(0, 10u, 0u, 0u, 9u, 55555u);
    net_lost_connect_probe(p);
    CHECK((g_ev_n == 0) && (p->state == NET_SOCK_STATE_CLOSED),
          "TC-NETEV-042b current state: self-heal cannot accept once the software side is CLOSED (logged only, no invented session)");
}

/* ===================== 周期对账 ===================== */

static void recon_step(uint32_t now)
{
    g_now = now;
    net_reconcile_tick();
}

static void tc_reconcile(void)
{
    net_sock_t *p;
    int infos;
    int c;

    printf("-- TC-NETEV-050..058 reconcile --\n");
    /* 对账器里的 s_last / s_bad[] / s_cool[] 是函数内 static（外部够不着），
     * 所以每个形态**各占一个 fd**、时间统一单调前进，互不串扰。 */
    reset_all();
    infos = g_nev_info_count;
    recon_step(1000u);                       /* priming：链路计数记基线 */
    CHECK(g_nev_info_count == infos,
          "TC-NETEV-051a the first pass after power-up logs nothing for the link counter (the 0xFFFF sentinel only records the baseline)");
    c = g_chip.cached_calls;
    recon_step(1000u);                       /* 同一时刻再调一次 */
    CHECK(g_chip.cached_calls == c, "TC-NETEV-050 100ms period gate: do not query the chip twice at the same instant");

    reset_all();
    p = mk(1, NET_SOCK_STATE_ESTABLISHED, 2404u);
    g_fake.cached_open[1] = CH395F_SOCKET_CLOSED;
    g_fake.cached_tcp[1] = CH395F_TCP_CLOSED;
    infos = g_nev_info_count;
    recon_step(1100u);
    recon_step(1200u);
    recon_step(1300u);
    CHECK((p->state == NET_SOCK_STATE_ESTABLISHED) && (g_ev_n == 0) &&
          (g_nev_info_count == infos),
          "TC-NETEV-052 a dead session needs 4 consecutive observations before acting: the first three change nothing");
    recon_step(1400u);
    CHECK((p->state == NET_SOCK_STATE_CLOSED) && (p->session_dead == 1u) &&
          (g_ev_kind[0] == (int)NET_EVENT_DISCONNECTED),
          "TC-NETEV-052b once the 4th observation is stable, run the disconnect teardown");
    p->state = NET_SOCK_STATE_ESTABLISHED;    /* 假装又活了，验证冷却 */
    recon_step(1500u);
    recon_step(1600u);
    recon_step(1700u);
    recon_step(1800u);
    CHECK(g_ev_n == 1, "TC-NETEV-052c no repeat action inside the 1000ms cooldown after acting (even when the stable count is met)");

    reset_all();
    p = mk(2, NET_SOCK_STATE_ESTABLISHED, 2404u);
    g_fake.cached_open[2] = CH395F_SOCKET_OPEN;
    g_fake.cached_tcp[2] = CH395F_TCP_LISTEN;   /* 芯片自己重开监听了，却没发 DISCONNECT */
    recon_step(2900u);
    CHECK((p->state == NET_SOCK_STATE_ESTABLISHED) && (g_pcan_n == 0),
          "TC-NETEV-053 the chip reopened the listener behind our back: needs 2 stable passes, the first one only accumulates");
    recon_step(3000u);
    CHECK((p->state == NET_SOCK_STATE_LISTENING) && (g_pcan_n == 1) &&
          (g_scan_n == 1) && (g_pcan_err == NET_ERR_CONNRESET),
          "TC-NETEV-053b second stable pass: resync to listen and cancel both pending waits (otherwise a task would wait forever)");

    reset_all();
    p = mk(3, NET_SOCK_STATE_LISTENING, 2404u);
    p->last_peer_port = 1u;
    g_fake.cached_tcp[3] = CH395F_TCP_ESTABLISHED;   /* 连上了却没 CONNECT 中断 */
    ch395f_fake_set_peer(3, 172u, 16u, 0u, 5u, 40000u);
    recon_step(4100u);
    CHECK((p->state == NET_SOCK_STATE_ESTABLISHED) && (p->remote_port == 40000u) &&
          (g_ev_kind[0] == (int)NET_EVENT_CONNECTED),
          "TC-NETEV-054 connect completed but the interrupt was lost: a single pass is enough to make up the accept");

    reset_all();
    p = mk(4, NET_SOCK_STATE_LISTENING, 2404u);
    g_fake.cached_open[4] = CH395F_SOCKET_CLOSED;    /* 监听没了 */
    g_fake.cached_tcp[4] = CH395F_TCP_CLOSED;
    recon_step(5200u);
    recon_step(5300u);
    CHECK((g_req_n == 1) && (g_req_sock == 4) &&
          (g_req_reason == (int)NET_LISTENER_REQ_RECON),
          "TC-NETEV-055 listener lost: request a reopen after 2 stable passes (the event layer does not open it itself)");

    reset_all();
    p = mk(5, NET_SOCK_STATE_CLOSED, 2404u);
    g_fake.cached_open[5] = CH395F_SOCKET_OPEN;      /* 芯片还在 LISTEN */
    g_fake.cached_tcp[5] = CH395F_TCP_LISTEN;
    p->remote_port = 999u;
    p->lost_conn_seen = 1u;
    recon_step(6400u);
    CHECK((p->state == NET_SOCK_STATE_LISTENING) && (p->last_peer_port == 999u) &&
          (p->lost_conn_seen == 0u) && (g_req_n == 0),
          "TC-NETEV-056 U11 resync: software CLOSED while the chip is LISTEN -> follow the chip, no redundant reopen");

    reset_all();
    p = mk(6, NET_SOCK_STATE_CLOSED, 2404u);
    g_fake.cached_open[6] = CH395F_SOCKET_CLOSED;
    recon_step(7500u);
    recon_step(7600u);
    CHECK((g_req_n == 1) && (g_req_sock == 6),
          "TC-NETEV-057 software CLOSED and the chip is not listening either: request a reopen (the listener layer rebuilds it)");

    reset_all();
    (void)memset(&g_tbl[7], 0, sizeof(g_tbl[7]));    /* 槽位不在用 */
    infos = g_nev_info_count;
    recon_step(8700u);
    CHECK(g_nev_info_count == infos, "TC-NETEV-058 unused slots are skipped outright (no action at all)");

    /* 链路日志：s_link_last 初值 0xFFFF 是哨兵——第一次看到计数只记基线、不打日志
     * （否则每次上电都会冒一条"链路 up"的假事件）；此后计数一变就必须留痕。
     * 本文件开头那次 priming 就是"基线"那一趟（TC-NETEV-051a），这里是"变化"那一趟。 */
    reset_all();
    g_fake.link_change = 7u;
    infos = g_nev_info_count;
    recon_step(9800u);
    CHECK(g_nev_info_count == (infos + 1),
          "TC-NETEV-051b any change of the link-change counter is logged (the baseline pass is already covered by 051a)");
}

int main(void)
{
    printf("=== NET Events Tests ===\n");

    tc_connect();
    tc_disconnect();
    tc_recv_send_timeout();
    tc_lost_probe();
    tc_reconcile();

    printf("\n=== NET Events Tests: %d/%d PASSED (failed=%d) ===\n",
           s_passed, s_total, s_failed);
    return (s_failed == 0) ? 0 : 1;
}