STM32F4-Base/test/host/time_sync/time_sync_test.c

/*
 * 模块名称：Time Sync（PC 本地时间推送接收）主机侧单元测试
 * 模块功能：在 PC 上对 App/sync/time_sync.c 做离线验证（4 个函数全覆盖：
 *           time_sync_delay_fed / time_sync_open_listener / time_sync_handle_conn /
 *           time_sync_task）。
 *
 * 被测对象：真实源文件 ../../../App/sync/time_sync.c（以 #include 原样纳入，
 *           保证测的是生产代码而非副本）。平台依赖由本文件提供的**可注入桩**实现：
 *             - FreeRTOS/task.h   -> vTaskDelay / xTaskGetTickCount（可控时钟）
 *             - net_socket.h      -> socket/bind/listen/accept/close/recv_to/
 *                                    get_generation/htons（全部脚本化）
 *             - sys_events.h      -> osEventFlagsWait（可注入"未就绪"）
 *             - sys_clock.h       -> sys_clock_set_unix（记录 epoch）
 *             - task_watchdog.h   -> task_wd_beat / task_wd_bind（记录心跳节奏）
 *             - dbg_log.h         -> DBG_ERROR/DBG_INFO 计数
 *
 * 为什么要主机侧单测（而不是只用板端套件）：
 *   1. **本模块是 N-17 的当事方**：登记簿 N-17 记录"time_sync 监听重建期间心跳缺口
 *      800ms~1s，距 IWDG 最坏超时 1701ms 余量仅 ~0.7s"。缺口的成因全部是本模块的
 *      **纯逻辑**——分片延时（delay_fed）的心跳节奏、监听重试退避（500/2000ms）、
 *      accept 轮询退避（200ms）、收尾延时（50ms）、以及"屏障等待态也要喂心跳"。
 *      这些在真机上只能靠"跑起来看复位不复位"间接观察，主机侧可**逐片断言**。
 *   2. **时间包重组状态机**（handle_conn）是纯逻辑：累积到 8 字节才解析、30s 总预算
 *      随 tick 推进耗尽、TCP 分段送达、EOF/真错误/超时三种返回码分支——板端套件
 *      无法精确构造"分段 + 预算耗尽 + tick 回绕"的组合。
 *   3. 不占 MCU 的 RAM，毫秒级完成。
 *
 * 覆盖点（TC-TS-xxx）：
 *   —— time_sync_delay_fed（可喂心跳的分片延时）——
 *   TC-TIMESYNC-001 0ms 不睡眠不喂狗
 *   TC-TIMESYNC-002 恰好一片（50ms）
 *   TC-TIMESYNC-003 非整片（120ms）切成 50/50/20，每片喂心跳
 *   TC-TIMESYNC-004 长延时（2000ms）= 40 片 × 50ms，每片喂心跳
 *   TC-TIMESYNC-005 不足一片（49ms）单片处理
 *   TC-TIMESYNC-006 总预算 30s = 600 片（片长上限恒 50ms）
 *   —— time_sync_open_listener（监听建立与重试）——
 *   TC-TIMESYNC-010 首次成功：socket/bind/listen 各一次，端口经 net_htons，无退避
 *   TC-TIMESYNC-011 bind 失败 -> 关 socket + 退避 2000ms + 留痕，随后重试成功
 *   TC-TIMESYNC-012 listen 失败 -> 关 socket + 退避 2000ms，随后重试成功
 *   TC-TIMESYNC-013 socket 连续失败 -> 5 次后返回 -1（5 条 ERROR，5×500ms 退避）
 *   TC-TIMESYNC-014 第 3 次重试成功并返回新描述符
 *   TC-TIMESYNC-015 每次重试前 + 每片延时各喂一次心跳，且心跳位恒为 TIMESYNC
 *   —— time_sync_handle_conn（时间包重组状态机）——
 *   TC-TIMESYNC-020 8 字节一次收齐 -> 大端解析 epoch + 更新墙钟 + 关连接
 *   TC-TIMESYNC-021 分段送达（4+4）-> 累积后解析；第二次只请求剩余 12 字节
 *   TC-TIMESYNC-022 一次到达 16 字节 -> 只取前 8 字节
 *   TC-TIMESYNC-023 前缀非 "TIME" -> 不更新墙钟，但仍关连接
 *   TC-TIMESYNC-024 对端关闭（n==0）-> 立即退出、不解析
 *   TC-TIMESYNC-025 真错误（n==-1）-> 立即退出、不解析
 *   TC-TIMESYNC-026 只收到 4 字节后 EOF -> 不足 8 字节不解析
 *   TC-TIMESYNC-027 30s 预算耗尽 -> 留痕 "no TIME packet in 30s, drop conn"
 *   TC-TIMESYNC-028 剩余预算不足一片 -> 末片按剩余（20ms）切分
 *   TC-TIMESYNC-029 32 位 tick 回绕 -> 预算计算仍正确
 *   —— time_sync_task（任务主循环）——
 *   TC-TIMESYNC-040 sys_evtHandle==NULL：跳过就绪屏障；accept 轮询->成功->处理->收尾
 *   TC-TIMESYNC-041 就绪屏障：100ms 分片等待 NET_READY（osFlagsNoClear 不消费就绪位）
 *   TC-TIMESYNC-042 屏障未就绪期间持续喂心跳（2026-10-02 台架根因的回归防线）
 *   TC-TIMESYNC-043 网络代次变化 -> 关闭旧监听并重监听
 *   TC-TIMESYNC-044 监听建立失败 -> 5 次重试后放弃并退避 2000ms
 *
 * 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：2026-10-10
 */

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

/* ===================== 平台桩（先纳入，覆盖真实头） ===================== */
#include "FreeRTOS.h"
#include "task.h"
#include "net_socket.h"
#include "sys_clock.h"
#include "sys_events.h"
#include "task_watchdog.h"   /* 真实头（App/util）：task_wd_id_t / TASK_WD_TIMESYNC */

/* ===================== FreeRTOS 桩 ===================== */
static TickType_t s_tick;
#define DELAY_LOG_MAX 800
static uint32_t s_delays[DELAY_LOG_MAX];
static int      s_delay_calls;

void vTaskDelay(TickType_t xTicksToDelay) {
    if (s_delay_calls < DELAY_LOG_MAX) {
        s_delays[s_delay_calls] = (uint32_t)xTicksToDelay;
    }
    s_delay_calls++;
}

TickType_t xTaskGetTickCount(void) {
    return s_tick;
}

/* ===================== CMSIS-RTOS 事件标志桩 ===================== */
osEventFlagsId_t sys_evtHandle = NULL;

static uint32_t s_evt_seq[8];
static int      s_evt_seq_n;
static uint32_t s_evt_default = 0xFFFFFFFFu;   /* 未脚本化时的返回值（默认：就绪） */
static int      s_evt_calls;
static int      s_evt_longjmp_at = -1;         /* >0 时第 N 次调用触发 longjmp */
static uint32_t s_evt_last_flags;
static uint32_t s_evt_last_options;
static uint32_t s_evt_last_timeout;

static jmp_buf s_jmp;

uint32_t osEventFlagsWait(osEventFlagsId_t ef_id, uint32_t flags, uint32_t options, uint32_t timeout) {
    int i = s_evt_calls;
    (void)ef_id;

    s_evt_last_flags = flags;
    s_evt_last_options = options;
    s_evt_last_timeout = timeout;
    s_evt_calls++;

    if (s_evt_longjmp_at > 0 && (i + 1) >= s_evt_longjmp_at) {
        longjmp(s_jmp, 2);            /* 跳出 time_sync_task 的屏障循环（用例收尾） */
    }
    if (i < s_evt_seq_n) {
        return s_evt_seq[i];
    }
    return s_evt_default;
}

/* ===================== 看门狗桩 ===================== */
static int s_beat_calls;
static int s_beat_id_bad;
/* ⚠ 命名必须与 net_socket 桩的 net_bind 计数区分开：C 的"暂定定义"规则下，
 *   同一编译单元里两个 `static int x;` 会被**静默合并为同一个对象**（不报错），
 *   于是 task_wd_bind 与 net_bind 会共用计数器，断言全部失真（2026-10-10 踩过）。 */
static int s_wd_bind_calls;
static int s_wd_bind_id_bad;

void task_wd_beat(task_wd_id_t id) {
    s_beat_calls++;
    if (id != TASK_WD_TIMESYNC) {
        s_beat_id_bad++;
    }
}

void task_wd_bind(task_wd_id_t id) {
    s_wd_bind_calls++;
    if (id != TASK_WD_TIMESYNC) {
        s_wd_bind_id_bad++;
    }
}

/* ===================== sys_clock 桩 ===================== */
static int      s_set_unix_calls;
static uint32_t s_set_unix_last;

int sys_clock_set_unix(uint32_t unix_secs) {
    s_set_unix_calls++;
    s_set_unix_last = unix_secs;
    return 0;
}

/* ===================== net_socket 桩 ===================== */
static uint16_t s_htons_last;

static int s_socket_calls;
static int s_socket_seq[8];
static int s_socket_seq_n;
static int s_socket_default = 5;

static int      s_bind_calls;
static int      s_bind_seq[8];
static int      s_bind_seq_n;
static uint16_t s_bind_port;
static uint16_t s_bind_family;

static int s_listen_calls;
static int s_listen_seq[8];
static int s_listen_seq_n;

static int s_accept_calls;
static int s_accept_seq[16];
static int s_accept_seq_n;

static int s_close_calls;
static int s_close_socks[32];

static uint32_t s_gen_seq[8];
static int      s_gen_seq_n;
static uint32_t s_gen_default = 1u;
static int      s_gen_calls;
static int      s_gen_longjmp_at = -1;          /* >0 时第 N 次调用触发 longjmp */

uint16_t net_htons(uint16_t hostshort) {
    s_htons_last = hostshort;
    return (uint16_t)(((hostshort & 0xFFu) << 8) | (hostshort >> 8));
}

int net_socket(int domain, int type) {
    int i = s_socket_calls++;
    (void)domain;
    (void)type;
    return (i < s_socket_seq_n) ? s_socket_seq[i] : s_socket_default;
}

int net_bind(int sockfd, const struct net_sockaddr *addr, int addrlen) {
    const struct net_sockaddr_in *a = (const struct net_sockaddr_in *)addr;
    int i = s_bind_calls++;

    (void)sockfd;
    (void)addrlen;
    s_bind_family = a->sin_family;
    s_bind_port = a->sin_port;
    return (i < s_bind_seq_n) ? s_bind_seq[i] : 0;
}

int net_listen(int sockfd) {
    int i = s_listen_calls++;
    (void)sockfd;
    return (i < s_listen_seq_n) ? s_listen_seq[i] : 0;
}

int net_accept(int sockfd, struct net_sockaddr *addr, int *addrlen) {
    int i = s_accept_calls++;
    (void)sockfd;
    (void)addr;
    (void)addrlen;
    return (i < s_accept_seq_n) ? s_accept_seq[i] : -1;
}

int net_close(int sockfd) {
    if (s_close_calls < 32) {
        s_close_socks[s_close_calls] = sockfd;
    }
    s_close_calls++;
    return 0;
}

/* ---- net_drop_conn（E-02 收口）：计数 + 记录 fd ---- */
static int s_drop_calls;
static int s_drop_socks[32];

int net_drop_conn(int sockfd) {
    if (s_drop_calls < 32) {
        s_drop_socks[s_drop_calls] = sockfd;
    }
    s_drop_calls++;
    return 0;
}

uint32_t net_get_generation(void) {
    int i = s_gen_calls++;

    if (s_gen_longjmp_at > 0 && (i + 1) >= s_gen_longjmp_at) {
        longjmp(s_jmp, 1);            /* 跳出 time_sync_task 的主循环（用例收尾） */
    }
    return (i < s_gen_seq_n) ? s_gen_seq[i] : s_gen_default;
}

/* ---- net_recv_to：脚本化返回码 + 可推进 tick ---- */
typedef struct {
    int      n;                 /* 返回码：>0 字节数 / 0 EOF / -1 错误 / -2 超时无数据 */
    uint8_t  data[16];          /* 要"送达"的字节 */
    int      len;               /* data 有效长度 */
    uint32_t tick_adv;          /* 返回前把假时钟推进多少 ms */
} recv_step_t;

static recv_step_t s_recv_seq[16];
static int         s_recv_seq_n;
static int         s_recv_idx;
static int         s_recv_calls;
static int         s_recv_default = 0;          /* 脚本用尽后的返回码（0=EOF，保证循环终止） */
static uint32_t    s_recv_to_log[64];
static int         s_recv_len_log[64];

int net_recv_to(int sockfd, void *buf, int len, uint32_t timeout_ms) {
    int i = s_recv_calls;

    (void)sockfd;
    if (i < 64) {
        s_recv_to_log[i] = timeout_ms;
        s_recv_len_log[i] = len;
    }
    s_recv_calls++;

    if (s_recv_idx >= s_recv_seq_n) {
        return s_recv_default;
    }

    {
        const recv_step_t *st = &s_recv_seq[s_recv_idx];
        int copy;
        s_recv_idx++;
        s_tick += st->tick_adv;
        if (st->n <= 0) {
            return st->n;
        }
        copy = (st->n <= len) ? st->n : len;
        if (copy > st->len) {
            copy = st->len;
        }
        if ((copy > 0) && (buf != NULL)) {
            memcpy(buf, st->data, (size_t)copy);
        }
        return st->n;
    }
}

/* ===================== 断言 ===================== */
static int s_total = 0, s_passed = 0, s_failed = 0;
int g_tstest_err_count = 0;
int g_tstest_info_count = 0;

#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)

/* ===================== 被测代码（原样纳入生产源） ===================== */
#include "time_sync.c"

/* ===================== 工具 ===================== */

/*
 * 函数功能：把全部桩复位到"健康"初值
 * 入口参数：无
 * 返 回 值：无
 * 限定条件：无
 * 函数说明：默认 = 网络全成功、gen 恒为 1、recv 脚本为空（脚本用尽返回 EOF）、
 *          事件标志恒就绪。各用例按需覆盖。
 */
static void fakes_reset(void) {
    s_tick = 0;
    s_delay_calls = 0;

    sys_evtHandle = NULL;
    s_evt_seq_n = 0;
    s_evt_default = SYS_EVT_NET_READY;   /* 健康默认：就绪 */
    s_evt_calls = 0;
    s_evt_longjmp_at = -1;
    s_evt_last_flags = 0;
    s_evt_last_options = 0;
    s_evt_last_timeout = 0;

    s_beat_calls = 0;
    s_beat_id_bad = 0;
    s_wd_bind_calls = 0;
    s_wd_bind_id_bad = 0;

    s_set_unix_calls = 0;
    s_set_unix_last = 0;

    s_htons_last = 0;
    s_socket_calls = 0;
    s_socket_seq_n = 0;
    s_socket_default = 5;
    s_bind_calls = 0;
    s_bind_seq_n = 0;
    s_bind_port = 0;
    s_bind_family = 0;
    s_listen_calls = 0;
    s_listen_seq_n = 0;
    s_accept_calls = 0;
    s_accept_seq_n = 0;
    s_close_calls = 0;
    s_drop_calls = 0;
    s_gen_seq_n = 0;
    s_gen_default = 1u;
    s_gen_calls = 0;
    s_gen_longjmp_at = -1;

    s_recv_seq_n = 0;
    s_recv_idx = 0;
    s_recv_calls = 0;
    s_recv_default = 0;

    g_tstest_err_count = 0;
    g_tstest_info_count = 0;
}

/* 装配一个 recv 脚本步 */
static void recv_set(int idx, int n, const uint8_t *data, int len, uint32_t tick_adv) {
    memset(&s_recv_seq[idx], 0, sizeof(s_recv_seq[idx]));
    s_recv_seq[idx].n = n;
    s_recv_seq[idx].len = len;
    s_recv_seq[idx].tick_adv = tick_adv;
    if ((data != NULL) && (len > 0)) {
        int copy = (len > 16) ? 16 : len;
        memcpy(s_recv_seq[idx].data, data, (size_t)copy);
    }
}

/* 装配一个 "TIME" + uint32 大端 时间包 */
static void make_time_packet(uint8_t *out, uint32_t epoch) {
    out[0] = (uint8_t)'T';
    out[1] = (uint8_t)'I';
    out[2] = (uint8_t)'M';
    out[3] = (uint8_t)'E';
    out[4] = (uint8_t)(epoch >> 24);
    out[5] = (uint8_t)(epoch >> 16);
    out[6] = (uint8_t)(epoch >> 8);
    out[7] = (uint8_t)(epoch);
}

/* 检查 s_delays[0..n) 是否全部等于 v */
static int delays_all(uint32_t v, int n) {
    int k;
    for (k = 0; k < n; k++) {
        if (s_delays[k] != v) {
            return 0;
        }
    }
    return 1;
}

/* ===================== TC-TIMESYNC-001..006：delay_fed ===================== */

static void tc_delay_fed(void) {
    fakes_reset();
    time_sync_delay_fed(0U);
    CHECK((s_beat_calls == 0) && (s_delay_calls == 0), "TC-TIMESYNC-001 delay_fed(0) neither sleeps nor beats");

    fakes_reset();
    time_sync_delay_fed(50U);
    CHECK((s_beat_calls == 1) && (s_delay_calls == 1) && (s_delays[0] == 50U),
          "TC-TIMESYNC-002 delay_fed(50) = one 50 ms slice + 1 beat");

    fakes_reset();
    time_sync_delay_fed(120U);
    CHECK((s_beat_calls == 3) && (s_delay_calls == 3), "TC-TIMESYNC-003 delay_fed(120) splits into 3 slices");
    CHECK((s_delays[0] == 50U) && (s_delays[1] == 50U) && (s_delays[2] == 20U),
          "TC-TIMESYNC-003b slice lengths 50/50/20 (last slice is the remainder)");

    fakes_reset();
    time_sync_delay_fed(2000U);
    CHECK((s_delay_calls == 40) && (s_beat_calls == 40) && delays_all(50U, 40),
          "TC-TIMESYNC-004 delay_fed(2000) = 40 slices x 50 ms, one beat per slice");

    fakes_reset();
    time_sync_delay_fed(49U);
    CHECK((s_beat_calls == 1) && (s_delays[0] == 49U), "TC-TIMESYNC-005 less than one slice (49 ms) handled as a single slice");

    fakes_reset();
    time_sync_delay_fed(30000U);
    CHECK(s_delay_calls == 600, "TC-TIMESYNC-006 total budget 30 s = 600 slices (slice cap is always 50 ms)");
}

/* ===================== TC-TIMESYNC-010..015：open_listener ===================== */

static void tc_open_listener(void) {
    fakes_reset();
    {
        int s = time_sync_open_listener();
        CHECK(s == 5, "TC-TIMESYNC-010 open_listener success returns the socket descriptor");
        CHECK((s_socket_calls == 1) && (s_bind_calls == 1) && (s_listen_calls == 1),
              "TC-TIMESYNC-010b socket / bind / listen called once each");
        CHECK(s_htons_last == (uint16_t)TIME_SYNC_PORT, "TC-TIMESYNC-010c port goes through net_htons(8888)");
        CHECK(s_bind_port == net_htons((uint16_t)TIME_SYNC_PORT), "TC-TIMESYNC-010d sin_port is in network byte order");
        CHECK(s_bind_family == (uint16_t)NET_AF_INET, "TC-TIMESYNC-010e sin_family = NET_AF_INET");
        CHECK(s_delay_calls == 0, "TC-TIMESYNC-010f no backoff delay on the success path");
    }

    fakes_reset();
    s_bind_seq[0] = -1;
    s_bind_seq_n = 1;
    {
        int s = time_sync_open_listener();
        CHECK(s == 5, "TC-TIMESYNC-011 bind succeeds on retry after one failure");
        CHECK((s_close_calls == 1) && (s_close_socks[0] == 5), "TC-TIMESYNC-011b bind failure closes that socket");
        CHECK(s_delay_calls == 40, "TC-TIMESYNC-011c bind failure backs off 2000 ms (40 slices)");
        CHECK(g_tstest_err_count == 1, "TC-TIMESYNC-011d bind failure leaves a DBG_ERROR trace");
    }

    fakes_reset();
    s_listen_seq[0] = -1;
    s_listen_seq_n = 1;
    {
        int s = time_sync_open_listener();
        CHECK(s == 5, "TC-TIMESYNC-012 listen succeeds on retry after one failure");
        CHECK((s_close_calls == 1) && (s_close_socks[0] == 5), "TC-TIMESYNC-012b listen failure closes that socket");
        CHECK(s_delay_calls == 40, "TC-TIMESYNC-012c listen failure backs off 2000 ms");
    }

    fakes_reset();
    s_socket_default = -1;
    {
        int s = time_sync_open_listener();
        CHECK(s == -1, "TC-TIMESYNC-013 socket keeps failing -> returns -1");
        CHECK(s_socket_calls == 5, "TC-TIMESYNC-013b retry cap is 5 attempts");
        CHECK(g_tstest_err_count == 5, "TC-TIMESYNC-013c every failure leaves its own trace (5 DBG_ERROR lines)");
        CHECK(s_delay_calls == 50, "TC-TIMESYNC-013d every failure backs off 500 ms (5 x 10 slices)");
    }

    fakes_reset();
    s_socket_seq[0] = -1;
    s_socket_seq[1] = -1;
    s_socket_seq[2] = 9;
    s_socket_seq_n = 3;
    {
        int s = time_sync_open_listener();
        CHECK(s == 9, "TC-TIMESYNC-014 3rd retry succeeds and returns the new descriptor");
        CHECK(s_socket_calls == 3, "TC-TIMESYNC-014b exactly 3 attempts");
        CHECK(s_delay_calls == 20, "TC-TIMESYNC-014c two failures back off 500 ms x 2");
    }

    fakes_reset();
    s_socket_default = -1;
    (void)time_sync_open_listener();
    CHECK(s_beat_calls == 55, "TC-TIMESYNC-015 every retry round (5) + every delay slice (50) beats once");
    CHECK(s_beat_id_bad == 0, "TC-TIMESYNC-015b the beat bit is always TASK_WD_TIMESYNC");
}

/* ===================== TC-TIMESYNC-020..029：handle_conn =====================
 * ⚠ 契约变更：handle_conn **不再** net_close
 * （单连接模式下 conn==listen，close 会连监听一起毁）；会话收尾只返回外层，
 * 由 time_sync_task 在 `conn != ls`（模拟器多连接后端）时才关数据 fd。
 * 故本组断言一律为 s_close_calls == 0；任务级关闭见 TC-TIMESYNC-040e。 */

static void tc_handle_conn(void) {
    uint8_t pkt[16];

    /* 1) 8 字节一次收齐 */
    fakes_reset();
    make_time_packet(pkt, 0x12345678u);
    recv_set(0, 8, pkt, 8, 0U);
    s_recv_seq_n = 1;
    s_tick = 100U;
    time_sync_handle_conn(7);
    CHECK(s_set_unix_calls == 1, "TC-TIMESYNC-020 TIME packet in one shot -> wall clock updated once");
    CHECK(s_set_unix_last == 0x12345678u, "TC-TIMESYNC-020b epoch parsed big-endian");
    CHECK((s_recv_calls == 1) && (s_recv_len_log[0] == 16), "TC-TIMESYNC-020c the first request asks for 16 bytes");
    CHECK(s_recv_to_log[0] == 50U, "TC-TIMESYNC-020d single wait slice length = 50 ms");
    CHECK(s_close_calls == 0, "TC-TIMESYNC-020e after handling, the connection is **not** closed (close is the outer conn!=ls branch job)");
    CHECK(s_drop_calls == 0, "TC-TIMESYNC-020g a successful session is not torn down (drop is only for give-up paths)");
    CHECK(g_tstest_info_count == 1, "TC-TIMESYNC-020f leaves the wall clock updated trace");

    /* 2) 分段送达：4 + 4 */
    fakes_reset();
    make_time_packet(pkt, 10u);
    recv_set(0, 4, pkt, 4, 10U);
    recv_set(1, 4, pkt + 4, 4, 10U);
    s_recv_seq_n = 2;
    time_sync_handle_conn(3);
    CHECK((s_set_unix_calls == 1) && (s_set_unix_last == 10u), "TC-TIMESYNC-021 pieces accumulate and then parse correctly");
    CHECK(s_recv_calls == 2, "TC-TIMESYNC-021b read twice");
    CHECK((s_recv_len_log[0] == 16) && (s_recv_len_log[1] == 12),
          "TC-TIMESYNC-021c the second request asks only for the remaining 12 bytes");
    CHECK((s_recv_to_log[0] == 50U) && (s_recv_to_log[1] == 50U), "TC-TIMESYNC-021d 50 ms per slice (budget is ample)");

    /* 3) 16 字节一次到达（只取前 8） */
    fakes_reset();
    make_time_packet(pkt, 5u);
    recv_set(0, 16, pkt, 16, 0U);
    s_recv_seq_n = 1;
    time_sync_handle_conn(4);
    CHECK((s_set_unix_calls == 1) && (s_set_unix_last == 5u), "TC-TIMESYNC-022 an over-long packet only takes the first 8 bytes");
    CHECK(s_recv_calls == 1, "TC-TIMESYNC-022b stops as soon as one read is enough");

    /* 4) 前缀不是 TIME */
    fakes_reset();
    pkt[0] = (uint8_t)'X';
    pkt[1] = (uint8_t)'X';
    pkt[2] = (uint8_t)'X';
    pkt[3] = (uint8_t)'X';
    pkt[4] = 0U;
    pkt[5] = 0U;
    pkt[6] = 0U;
    pkt[7] = 1U;
    recv_set(0, 8, pkt, 8, 0U);
    s_recv_seq_n = 1;
    time_sync_handle_conn(4);
    CHECK(s_set_unix_calls == 0, "TC-TIMESYNC-023 a non-TIME prefix does not update the wall clock");
    CHECK(s_close_calls == 0, "TC-TIMESYNC-023b a non-TIME prefix also does not close the connection");

    /* 5) 对端关闭（EOF） */
    fakes_reset();
    recv_set(0, 0, NULL, 0, 0U);
    s_recv_seq_n = 1;
    time_sync_handle_conn(6);
    CHECK((s_set_unix_calls == 0) && (s_recv_calls == 1), "TC-TIMESYNC-024 peer close (EOF) exits immediately without parsing");
    CHECK(s_close_calls == 0, "TC-TIMESYNC-024b EOF also does not close the connection (net-layer auto_relisten re-arms the listener)");

    /* 6) 真错误 */
    fakes_reset();
    recv_set(0, -1, NULL, 0, 0U);
    s_recv_seq_n = 1;
    time_sync_handle_conn(6);
    CHECK((s_recv_calls == 1) && (s_set_unix_calls == 0), "TC-TIMESYNC-025 a real error exits immediately without parsing");

    /* 7) 4 字节后 EOF */
    fakes_reset();
    make_time_packet(pkt, 7u);
    recv_set(0, 4, pkt, 4, 0U);
    recv_set(1, 0, NULL, 0, 0U);
    s_recv_seq_n = 2;
    time_sync_handle_conn(6);
    CHECK(s_set_unix_calls == 0, "TC-TIMESYNC-026 fewer than 8 bytes are not parsed");
    CHECK(s_recv_calls == 2, "TC-TIMESYNC-026b keeps waiting for the remaining bytes");

    /* 8) 30s 预算耗尽 */
    fakes_reset();
    recv_set(0, -2, NULL, 0, 30000U);
    s_recv_seq_n = 1;
    time_sync_handle_conn(6);
    CHECK(s_recv_calls == 1, "TC-TIMESYNC-027 no more reads once the budget is exhausted (only 1 read)");
    CHECK(g_tstest_info_count == 1, "TC-TIMESYNC-027b leaves the no TIME packet in 30s, drop conn trace");
    CHECK(s_close_calls == 0, "TC-TIMESYNC-027c budget exhausted still does not close the connection");
    CHECK(s_drop_calls == 1, "TC-TIMESYNC-027d budget exhausted drops the session on purpose (E-02 wrap-up: net_drop_conn kills the connection, keeps the listener)");

    /* 9) 剩余预算不足一片 */
    fakes_reset();
    recv_set(0, -2, NULL, 0, 29980U);
    s_recv_seq_n = 1;
    time_sync_handle_conn(6);
    CHECK(s_recv_calls == 2, "TC-TIMESYNC-028 ends after two waits");
    CHECK((s_recv_to_log[0] == 50U) && (s_recv_to_log[1] == 20U),
          "TC-TIMESYNC-028b second slice length = the remaining 20 ms");

    /* 10) 32 位 tick 回绕 */
    fakes_reset();
    s_tick = 0xFFFFFF00U;
    recv_set(0, -2, NULL, 0, 512U);          /* 推进后回绕到 0x00000100 */
    s_recv_seq_n = 1;
    time_sync_handle_conn(6);
    CHECK((s_recv_calls == 2) && (s_recv_to_log[0] == 50U) && (s_recv_to_log[1] == 50U),
          "TC-TIMESYNC-029 after a 32-bit tick wraparound the budget math is still correct");
}

/* ===================== TC-TIMESYNC-040..044：time_sync_task ===================== */

static void tc_task(void) {
    uint8_t pkt[16];

    /* A) 无就绪屏障（sys_evtHandle == NULL）：accept 轮询 2 次失败后成功 */
    fakes_reset();
    make_time_packet(pkt, 9u);
    recv_set(0, 8, pkt, 8, 0U);
    s_recv_seq_n = 1;
    s_accept_seq[0] = -1;
    s_accept_seq[1] = -1;
    s_accept_seq[2] = 7;
    s_accept_seq_n = 3;
    /* gen 调用序：iter1 顶部(1) + accept 两次失败各一次(2,3) + iter2 顶部(4) → 第 4 次跳出 */
    s_gen_longjmp_at = 4;
    if (setjmp(s_jmp) == 0) {
        time_sync_task(NULL);
    }
    CHECK((s_wd_bind_calls == 1) && (s_wd_bind_id_bad == 0),
          "TC-TIMESYNC-040 task entry registers the watchdog beat bit (task_wd_bind once)");
    CHECK(s_evt_calls == 0, "TC-TIMESYNC-040b skips the readiness barrier when sys_evtHandle==NULL");
    CHECK(s_accept_calls == 3, "TC-TIMESYNC-040c accept polled 3 times (2 with no connection + 1 success)");
    CHECK((s_set_unix_calls == 1) && (s_set_unix_last == 9u), "TC-TIMESYNC-040d the time packet arrived and the wall clock was updated");
    CHECK(s_close_calls == 1, "TC-TIMESYNC-040e the connection is closed once");
    CHECK(s_delay_calls == 9, "TC-TIMESYNC-040f delay slice count = 4+4+1 (200+200+50 ms)");
    CHECK(delays_all(50U, 9), "TC-TIMESYNC-040g every delay is sliced at 50 ms");
    CHECK(s_beat_calls == 13, "TC-TIMESYNC-040h beat count = main loop 1 + backoff 8 + accepted connection 1 + wrap-up 1 + next round 1");
    CHECK(s_beat_id_bad == 0, "TC-TIMESYNC-040i every beat sets the TIMESYNC bit");

    /* B) 就绪屏障：2 次未就绪 + 1 次就绪 */
    fakes_reset();
    sys_evtHandle = (osEventFlagsId_t)0x55;
    s_evt_seq[0] = osFlagsErrorTimeout;
    s_evt_seq[1] = osFlagsErrorTimeout;
    s_evt_seq[2] = SYS_EVT_NET_READY;
    s_evt_seq_n = 3;
    s_gen_longjmp_at = 1;
    if (setjmp(s_jmp) == 0) {
        time_sync_task(NULL);
    }
    CHECK(s_evt_calls == 3, "TC-TIMESYNC-041 readiness barrier polled 3 times (2 not ready + 1 ready)");
    CHECK(s_evt_last_timeout == 100U, "TC-TIMESYNC-041b barrier waits are sliced at 100 ms");
    CHECK(s_evt_last_flags == SYS_EVT_NET_READY, "TC-TIMESYNC-041c waits for the NET_READY bit");
    CHECK(s_evt_last_options == (osFlagsWaitAny | osFlagsNoClear), "TC-TIMESYNC-041d the ready bit is not consumed");
    CHECK(s_beat_calls == 3, "TC-TIMESYNC-041e the two not-ready rounds each beat once (+ 1 in the main loop)");
    CHECK(s_wd_bind_calls == 1, "TC-TIMESYNC-041f still registers the beat routing first");

    /* C) 屏障期间持续喂心跳（就绪位长期不置位） */
    fakes_reset();
    sys_evtHandle = (osEventFlagsId_t)0x55;
    s_evt_default = osFlagsErrorTimeout;
    s_evt_longjmp_at = 4;
    if (setjmp(s_jmp) == 0) {
        time_sync_task(NULL);
    }
    CHECK(s_evt_calls == 4, "TC-TIMESYNC-042 barrier waited 4 times, none ready (loop did not hang)");
    CHECK(s_beat_calls == 3, "TC-TIMESYNC-042b beats once after each not-ready round (before the 4th breaks out)");

    /* D) 网络代次变化 -> 关闭旧监听并重监听 */
    fakes_reset();
    s_gen_seq[0] = 1u;
    s_gen_seq[1] = 2u;
    s_gen_seq_n = 2;
    s_gen_default = 2u;
    s_gen_longjmp_at = 4;
    if (setjmp(s_jmp) == 0) {
        time_sync_task(NULL);
    }
    CHECK((s_close_calls == 1) && (s_close_socks[0] == 5), "TC-TIMESYNC-043 closes the old listener when the network generation changes");
    /* INFO 三条：两次 open_listener 成功各一条 "TCP listen on" + 一条 "network re-init, relisten" */
    CHECK(g_tstest_info_count == 3, "TC-TIMESYNC-043b leaves the network re-init, relisten trace (plus 2 listen-success lines)");
    CHECK(s_accept_calls == 2, "TC-TIMESYNC-043c polls accept only once per loop then gives up");
    CHECK((s_socket_calls == 2) && (s_bind_calls == 2) && (s_listen_calls == 2),
          "TC-TIMESYNC-043d the second loop rebuilt the listener");

    /* E) 监听建立失败 -> 5 次重试后放弃并退避 2000ms */
    fakes_reset();
    s_socket_default = -1;
    s_gen_longjmp_at = 2;
    if (setjmp(s_jmp) == 0) {
        time_sync_task(NULL);
    }
    CHECK(s_socket_calls == 5, "TC-TIMESYNC-044 open_listener gives up after 5 internal retries");
    CHECK(g_tstest_err_count == 6, "TC-TIMESYNC-044b 5 net_socket FAIL lines + 1 retry later line");
    CHECK(s_delay_calls == 90, "TC-TIMESYNC-044c backoff 5x500 ms + 2000 ms = 90 slices");
    CHECK(s_beat_calls == 97, "TC-TIMESYNC-044d beat count = 2 + 5 + 50 + 40");
    CHECK(s_beat_id_bad == 0, "TC-TIMESYNC-044e every beat sets the TIMESYNC bit");
}

/* ===================== main ===================== */

int main(void) {
    printf("=== Time Sync Tests ===\n");

    printf("-- delay_fed (heartbeat-fed slicing) --\n");
    tc_delay_fed();
    printf("-- open_listener (retry / backoff) --\n");
    tc_open_listener();
    printf("-- handle_conn (packet reassembly / budget) --\n");
    tc_handle_conn();
    printf("-- time_sync_task (barrier / accept / relisten) --\n");
    tc_task();

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