/* clock_abi_probe.c — 时钟 ABI 最小探针（M11）。
 *
 * 用途：在宿主或真机上一眼看出「编译器头文件声明的 time_t 宽度」与「libc 实际写入的
 * struct timespec 宽度」是否一致——这正是 meow_ui_time_ms 真机故障的根因（详见
 * sdk/CLOCK_ABI.md）。做法：先把 struct timespec 整块填 0xAA，再调 clock_gettime，
 * 看哪些字节被写回：
 *   - 正确（time64：tv_sec 8B + tv_nsec 4B）：偏移 0..11 被写，8..11 不再是 0xAA；
 *   - 坏（libc 只做 o32 time32：只写 8B）：偏移 8..11 仍是 0xAA → 退出码 2；
 *   - 头/库宽度相反（头 8B、库写 16B）也会在偏移检查里暴露。
 *
 * 构建（宿主）：
 *   gcc -Os -Wall -Wextra tools/clock_abi_probe.c -o clock_abi_probe
 * 构建（mipsel 静态，测裸 zig libc）：
 *   ~/.tools/zig-mipsel-cc -Os -static tools/clock_abi_probe.c -o clock_abi_probe
 * 构建（mipsel + SDK，测修复后的归档是否接管 clock_gettime）：
 *   ~/.tools/zig-mipsel-cc -Os -static -DMEOW_PROBE_WITH_SDK -I. -Iinclude \
 *       tools/clock_abi_probe.c meow_ui.a <sysroot>/lib/libz.a -lpthread -o clock_abi_probe_sdk
 *
 * 运行：./clock_abi_probe
 * 退出码：0=ABI 一致且时钟单调、量级合理；1=时钟值异常；2=libc 只写了 8 字节（ABI 不一致）。
 */
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <time.h>

#ifdef MEOW_PROBE_WITH_SDK
#include "meow_ui.h"
#endif

#define PAD_BYTE 0xAA

static uint64_t now_ms(void)
{
    struct timespec ts;
    clock_gettime(CLOCK_MONOTONIC, &ts);
    return (uint64_t)ts.tv_sec * 1000u + (uint64_t)ts.tv_nsec / 1000000u;
}

int main(void)
{
    int rc = 0;
    struct timespec ts;
    unsigned char raw[sizeof(struct timespec)];

    printf("sizeof(time_t)=%u sizeof(long)=%u sizeof(struct timespec)=%u\n",
           (unsigned)sizeof(time_t), (unsigned)sizeof(long), (unsigned)sizeof(struct timespec));
    printf("offsetof(tv_sec)=%u offsetof(tv_nsec)=%u\n",
           (unsigned)offsetof(struct timespec, tv_sec), (unsigned)offsetof(struct timespec, tv_nsec));

    memset(&ts, PAD_BYTE, sizeof ts);
    int r = clock_gettime(CLOCK_MONOTONIC, &ts);
    memcpy(raw, &ts, sizeof raw);
    printf("clock_gettime ret=%d tv_sec=%lld tv_nsec=%ld\n", r, (long long)ts.tv_sec, (long)ts.tv_nsec);
    printf("raw:");
    for (unsigned i = 0; i < sizeof raw; i++) printf(" %02x", raw[i]);
    printf("\n");

    if (r != 0) {
        printf("FAIL clock_gettime 失败\n");
        return 1;
    }
    /* tv_nsec 所在 4 字节必须被 libc 写过 */
    if (sizeof(struct timespec) > 8 && raw[8] == PAD_BYTE && raw[9] == PAD_BYTE &&
        raw[10] == PAD_BYTE && raw[11] == PAD_BYTE) {
        printf("FAIL libc 只写了 8 字节 time32（头声明 %u 字节）→ ABI 不一致\n",
               (unsigned)sizeof(struct timespec));
        rc = 2;
    }

    uint64_t a = now_ms();
    uint64_t b = now_ms();
    if (b < a || b - a > 5000 || b >= (1ULL << 40)) {
        printf("FAIL 毫秒值异常: a=%llu b=%llu\n",
               (unsigned long long)a, (unsigned long long)b);
        rc = rc ? rc : 1;
    } else {
        printf("ok   now_ms a=%llu b=%llu\n", (unsigned long long)a, (unsigned long long)b);
    }

#ifdef MEOW_PROBE_WITH_SDK
    uint64_t s1 = meow_ui_time_ms();
    uint64_t s2 = meow_ui_time_ms();
    printf("meow_ui_time_ms: %llu %llu\n", (unsigned long long)s1, (unsigned long long)s2);
    if (s2 < s1 || s2 - s1 > 5000 || s2 >= (1ULL << 40) || s2 == 0) {
        printf("FAIL meow_ui_time_ms 异常\n");
        rc = rc ? rc : 1;
    }
#endif

    printf(rc ? "== FAIL (rc=%d) ==\n" : "== PASS ==\n", rc);
    return rc;
}