MeowOS-For-R3P2/patch_v2/meow_svc_power/meow_svc_power.c

#define _GNU_SOURCE   /* 启用 struct ucred / SO_PEERCRED、asprintf 等 GNU/musl 扩展 */

/* meow_svc_power.c — MeowOS 电源管理专项子服务（SYSTEM_FRAMEWORK_SERVICES §1.2/§2.3/§2.4）。
 *
 * 单一二进制双形态：
 *   - svcd 以**空参**拉起（§1.3 conf `args=` 空）→ IPC 服务常驻：bind `/usr/data/meow_power.sock`
 *     （`--sock`/`MEOW_IPC_POWER_SOCK` 可覆盖），收 MSG_HELLO→MSG_ACK、MSG_POWER_ACTION→MSG_POWER_STATUS。
 *   - root shell `meow_svc_power <cmd>` → 一次性 CLI（免鉴权）执行对应动作（不常驻）。
 *
 * 动作逻辑与 launcher `power_menu.c` 的 `sys_do_reboot`/`set_boot_default_hiby`/`bootmode.sh Recovery`
 * **同源 0-diff 搬移**，仅入口（CLI vs IPC）与鉴权层不同。
 *
 * 鉴权（一期基础校验）：IPC 服务端受理 MSG_POWER_ACTION 前以 `SO_PEERCRED` 校验调用方 `uid==0`（root）
 * ——非 root 直接 `MEOW_ERR_PERM` 拒绝；完整 `os.meow.*` 包名鉴权（§5）留二期。CLI=root 免鉴权。
 *
 * 通知转储归属（§3.2/§3.3 已定案）：通知存储为 launcher 进程内存（meow_notif.c g_slots[]），服务跨进程
 * 不可达——**转储由调用方 launcher 先做**，服务对关机/重启/升级一律 `sync()` 落盘，不重实现转储。
 *
 * 编译（mipsel 静态）：build_svc_power.sh；宿主编译 build_svc_power.sh host。
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <stdarg.h>
#include <stdint.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <signal.h>
#include <poll.h>
#include <time.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <sys/syscall.h>
#include <sys/ioctl.h>

#include "meow_ipc.h"    /* 帧格式/消息号 + POWER_* 枚举 + m_power_* 负载（与 launcher 同源） */

/* ---- 路径常量（与 launcher 同源）---- */
#define FB_DEV           "/dev/fb0"
#define FBIOBLANK        0x4611
#define BACKLIGHT        "/sys/class/backlight/backlight_pwm0/brightness"
#define BACKLIGHT_POWER  "/sys/class/backlight/backlight_pwm0/bl_power"
#define BOOT_DEFAULT     "/data/meow_boot_default"   /* 0=MeowOS(默认),1=HibyOS */
#define COLD_BOOT        "/data/meow_cold_boot"      /* 冷启标记：1=上次关机,0=上次重启 */
#define MTD_OTA          "/dev/mtd5"                 /* ota 标记分区（8M） */
#define SETTINGS_FILE    "/usr/data/meow/settings.conf"
#define SETTINGS_HDR     "# meow-settings 1"
#define VERSION_FILE     "/etc/meowos_version"
#define BATT_CAP         "/sys/class/power_supply/battery/capacity"
#define BATT_STATUS      "/sys/class/power_supply/battery/status"
#define BATT_VOLT        "/sys/class/power_supply/battery/voltage_now"
#define DAC_NUMID        "amixer -c 0 cget numid=%d 2>/dev/null"

#define LINUX_REBOOT_MAGIC1     0xfee1dead
#define LINUX_REBOOT_MAGIC2     672274793        /* 0x28121969 */
#define LINUX_REBOOT_CMD_RESTART    0x01234567
#define LINUX_REBOOT_CMD_POWER_OFF  0x4321fedc

#define SV_PIPE_MAX     4096   /* popen_read_tmo 上限 */
#define SV_TIMEOUT_MS   1500   /* popen 子命令读超时 */

static const char *g_sock = "/usr/data/meow_power.sock";

/* ---------------- 极简日志（stderr；svcd supervisor 捕获） ---------------- */
static void svc_log(const char *fmt, ...)
{
    va_list ap;
    va_start(ap, fmt);
    fprintf(stderr, "[meow_svc_power] ");
    vfprintf(stderr, fmt, ap);
    fprintf(stderr, "\n");
    va_end(ap);
}

/* ---------------- 文件小工具 ---------------- */
/* 读整个文本文件到 buf（NUL 结尾），返回字节数（不含 NUL）；失败 -1。 */
static int read_file_txt(const char *path, char *buf, int cap)
{
    int fd = open(path, O_RDONLY);
    if (fd < 0) return -1;
    int n = 0;
    while (n < cap - 1) {
        ssize_t r = read(fd, buf + n, (size_t)(cap - 1 - n));
        if (r <= 0) break;
        n += (int)r;
    }
    close(fd);
    buf[n] = 0;
    while (n > 0 && (buf[n - 1] == '\n' || buf[n - 1] == '\r')) buf[--n] = 0;
    return n;
}

/* 读 int（atoi 首值）；失败默认 def。 */
static int read_file_int_def(const char *path, int def)
{
    char buf[32];
    if (read_file_txt(path, buf, sizeof buf) <= 0) return def;
    char *p = buf;
    while (*p == ' ' || *p == '\t') p++;
    int v = atoi(p);
    return v;
}

static int write_file_str(const char *path, const char *s, mode_t mode)
{
    int fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, mode);
    if (fd < 0) return -1;
    size_t l = strlen(s);
    ssize_t w = write(fd, s, l);
    int ok = (w == (ssize_t)l) ? 0 : -1;
    close(fd);
    return ok;
}

/* 读 settings.conf 某键值（key=value，行首忽略空白），找不到→def。 */
static int settings_get_int(const char *key, int def)
{
    FILE *f = fopen(SETTINGS_FILE, "r");
    if (!f) return def;
    char line[256];
    int val = def, found = 0;
    size_t klen = strlen(key);
    while (fgets(line, sizeof line, f)) {
        char *p = line;
        while (*p == ' ' || *p == '\t') p++;
        if (strncmp(p, key, klen) == 0 && p[klen] == '=') {
            val = atoi(p + klen + 1);
            found = 1;
            break;
        }
    }
    fclose(f);
    return found ? val : def;
}

/* 更新/插入 settings.conf 某键（保留头，O_TRUNC 重写）。成功 0。 */
static int settings_set_int(const char *key, int val)
{
    FILE *f = fopen(SETTINGS_FILE, "r");
    char tmp[1024];
    size_t klen = strlen(key);
    int found = 0;

    if (!f) {
        /* 无文件 → 新建头 + 键 */
        FILE *nf = fopen(SETTINGS_FILE, "w");
        if (!nf) return -1;
        fprintf(nf, "%s\n%s=%d\n", SETTINGS_HDR, key, val);
        fclose(nf);
        return 0;
    }
    /* 先把原文件读入 tmp（限 1KB，settings 为 KB 级小文件） */
    size_t n = 0;
    int c;
    while (n < sizeof tmp - 1 && (c = fgetc(f)) != EOF) tmp[n++] = (char)c;
    fclose(f);
    tmp[n] = 0;
    FILE *nf = fopen(SETTINGS_FILE, "w");
    if (!nf) return -1;
    /* 逐行写：头照抄；命中 key 行替换 */
    char *save = NULL;
    for (char *ln = strtok_r(tmp, "\n", &save); ln; ln = strtok_r(NULL, "\n", &save)) {
        char *p = ln;
        while (*p == ' ' || *p == '\t') p++;
        if (strncmp(p, key, klen) == 0 && p[klen] == '=') {
            fprintf(nf, "%s=%d\n", key, val);
            found = 1;
        } else {
            fprintf(nf, "%s\n", ln);
        }
    }
    if (!found) fprintf(nf, "%s=%d\n", key, val);
    fclose(nf);
    return 0;
}

/* ---------------- popen 限时读（kill 子进程防挂） ---------------- */
static char *popen_read_tmo(int tmo_ms, const char *cmd)
{
    int p[2];
    if (pipe(p) < 0) return NULL;
    pid_t pid = fork();
    if (pid < 0) { close(p[0]); close(p[1]); return NULL; }
    if (pid == 0) {
        dup2(p[1], 1);
        close(p[0]); close(p[1]);
        execl("/bin/sh", "sh", "-c", cmd, (char *)0);
        _exit(127);
    }
    close(p[1]);
    fcntl(p[0], F_SETFL, fcntl(p[0], F_GETFL, 0) | O_NONBLOCK);
    char *buf = malloc(SV_PIPE_MAX);
    if (!buf) { close(p[0]); waitpid(pid, NULL, 0); return NULL; }
    size_t off = 0;
    int remain = tmo_ms;
    while (remain > 0 && off < SV_PIPE_MAX - 1) {
        struct pollfd pf = { p[0], POLLIN, 0 };
        int r = poll(&pf, 1, remain);
        if (r < 0) { if (errno == EINTR) continue; break; }
        if (r == 0) break;                      /* 超时 */
        ssize_t rd = read(p[0], buf + off, SV_PIPE_MAX - 1 - off);
        if (rd == 0) break;                     /* EOF（子进程退出/关写端） */
        if (rd < 0) { if (errno == EAGAIN || errno == EWOULDBLOCK) continue; break; }
        off += (size_t)rd;
    }
    close(p[0]);
    waitpid(pid, NULL, 0);
    buf[off] = 0;
    return buf;
}

/* 前置声明：CLI 用法串（cli_run 用到）。 */
static const char *cli_usage(void);

/* ---------------- reboot / 关机 syscall ---------------- */
static void sys_reboot_do(int cmd)
{
    /* 与 power_menu.c sys_do_reboot 同源：sync() 落盘 → reboot(2) syscall → 永不返回。 */
    sync();
    svc_log("sys_reboot_do cmd=0x%x", cmd);
    syscall(SYS_reboot, LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, cmd, NULL);
    svc_log("sys_reboot_do returned: %s", strerror(errno));
    for (;;) usleep(1000);
}

/* ---------------- boot 默认 ---------------- */
/* 写 /data/meow_boot_default（0=MeowOS 默认 / 1=HibyOS 默认）。 */
static void write_boot_default(int v)
{
    char b[8];
    snprintf(b, sizeof b, "%d\n", v);
    if (write_file_str(BOOT_DEFAULT, b, 0644) < 0) svc_log("write %s fail: %s", BOOT_DEFAULT, strerror(errno));
    else svc_log("boot_default=%d", v);
}

/* ---------------- 关机 logo ---------------- */
static void show_shutdown_logo(void)
{
    /* 独立二进制 cmd_jpeg_display 能显图；SSH 无 fb 时重定向无害。 */
    int rc = system("PATH=/bin:/sbin:/usr/bin:/usr/sbin cmd_jpeg_display /etc/shutdown_logo.jpeg >/dev/null 2>&1");
    (void)rc;
}

/* ---------------- 升级（mtd5=ota:kernel2） ---------------- */
static void enter_upgrade(void)
{
    int rc = system("PATH=/bin:/sbin:/usr/bin:/usr/sbin /usr/bin/bootmode.sh Recovery >/dev/null 2>&1");
    (void)rc;
}

/* 读 /dev/mtd5 头，命中 "ota:kernel2" → 升级模式已设。 */
static int mtd_ota_is_upgrade(void)
{
    int fd = open(MTD_OTA, O_RDONLY);
    if (fd < 0) return 0;
    char buf[16];
    memset(buf, 0, sizeof buf);
    ssize_t n = read(fd, buf, sizeof buf - 1);
    close(fd);
    if (n <= 0) return 0;
    return strstr(buf, "ota:kernel2") != NULL;
}

/* ---------------- 有界拼接（printf 截断分析免疫；host/cross 均 0 warning） ---------------- */
static void cat_b(char *dst, size_t cap, const char *src)
{
    size_t dl = strlen(dst);
    if (dl >= cap - 1) return;
    size_t sl = strlen(src);
    if (sl > cap - 1 - dl) sl = cap - 1 - dl;
    if (sl) memcpy(dst + dl, src, sl);
    dst[dl + sl] = 0;
}

/* ---------------- 电池/状态读组（同 util.c/about.c/bootmenu 数据源） ---------------- */
static void battery_fill(char *out, int cap)
{
    int pct = read_file_int_def(BATT_CAP, -1);
    char st[32] = "";
    read_file_txt(BATT_STATUS, st, sizeof st);
    int mv = read_file_int_def(BATT_VOLT, -1) / 1000;   /* µV → mV */
    if (pct < 0) { snprintf(out, cap, "battery=unknown"); return; }
    char one[64];
    snprintf(one, sizeof one, "battery=%d%%(%s)", pct, st[0] ? st : "?");
    out[0] = 0;
    cat_b(out, cap, one);
    if (mv >= 0) { char more[24]; snprintf(more, sizeof more, " %dmV", mv); cat_b(out, cap, more); }
}

static const char *boot_default_str(void)
{
    int v = read_file_int_def(BOOT_DEFAULT, -1);
    if (v < 0) return "unknown";
    return v ? "hiby" : "meow";
}

static int cold_boot_flag(void) { return read_file_int_def(COLD_BOOT, -1); }

static void status_fill(char *out, int cap)
{
    char ver[32] = "-", batt[48] = "";
    if (read_file_txt(VERSION_FILE, ver, sizeof ver) <= 0 || !ver[0]) snprintf(ver, sizeof ver, "-");
    battery_fill(batt, sizeof batt);
    int cold = cold_boot_flag();
    char head[96];
    snprintf(head, sizeof head, "system=%s boot=%s upgrade=%s coldboot=%s ",
             ver, boot_default_str(),
             mtd_ota_is_upgrade() ? "yes" : "no",
             cold < 0 ? "unknown" : (cold ? "shutdown" : "reboot"));
    out[0] = 0;
    cat_b(out, cap, head);
    cat_b(out, cap, batt);
}

/* ---------------- 屏幕电源（同 launcher keys.c meow_panel_off/on + backlight.c） ---------------- */
static int backlight_write(int val)
{
    char b[16];
    snprintf(b, sizeof b, "%d", val);
    return write_file_str(BACKLIGHT, b, 0644) < 0 ? -1 : 0;
}

static int screen_on(void)
{
    int f = open(FB_DEV, O_RDWR);
    if (f >= 0) { ioctl(f, FBIOBLANK, 0); close(f); }
    int bri = settings_get_int("display.brightness", 60);
    int bmin = settings_get_int("display.brightness_min", 1);
    if (bri < bmin) bri = bmin;
    if (bri > 100) bri = 100;
    backlight_write(bri);
    svc_log("screen ON (brightness %d)", bri);
    return 0;
}

static int screen_off(void)
{
    int f = open(FB_DEV, O_RDWR);
    if (f >= 0) { ioctl(f, FBIOBLANK, 4); close(f); }
    backlight_write(0);
    svc_log("screen OFF (blank 4 + brightness 0)");
    return 0;
}

/* ---------------- DAC（CS43198） ---------------- */
/* 原机 cs43198 驱动 pwr_gpio=-1：无上电/下电控制点（sysfs/amixer），on/off 不支持。
 * status 仅报 amixer numid=1/2（L/R）当前音量上报值。 */
static int dac_status(char *out, int cap)
{
    char l[48] = "?", r[48] = "?";
    char *o1 = popen_read_tmo(SV_TIMEOUT_MS, "PATH=/bin:/sbin:/usr/bin:/usr/sbin amixer -c 0 cget numid=1 2>/dev/null");
    if (o1) {
        char *p = strstr(o1, ": values=");
        if (p) snprintf(l, sizeof l, "%.40s", p + 9);
        free(o1);
    }
    char *o2 = popen_read_tmo(SV_TIMEOUT_MS, "PATH=/bin:/sbin:/usr/bin:/usr/sbin amixer -c 0 cget numid=2 2>/dev/null");
    if (o2) {
        char *p = strstr(o2, ": values=");
        if (p) snprintf(r, sizeof r, "%.40s", p + 9);
        free(o2);
    }
    out[0] = 0;
    cat_b(out, cap, "dac=cs43198 L=");
    cat_b(out, cap, l);
    cat_b(out, cap, " R=");
    cat_b(out, cap, r);
    cat_b(out, cap, " powerctl=unsupported(no_gpio)");
    return 0;
}

static int dac_cmd(const char *sub, char *out, int cap)
{
    if (!sub) return MEOW_ERR_INVAL;
    if (!strcmp(sub, "status")) { return dac_status(out, cap); }
    if (!strcmp(sub, "on") || !strcmp(sub, "off")) {
        snprintf(out, cap, "DAC %s: unsupported (cs43198 pwr_gpio=-1, no on/off control point)", sub);
        return MEOW_ERR_NODEV;
    }
    return MEOW_ERR_INVAL;
}

/* ---------------- 动作执行（CLI + IPC 共用） ----------------
 * 返回 0 = 已同步执行并填好 st（调用方直接应答 st 给客户端/CLI 已打印）；
 * 返回 1 = 系统动作（关机/重启/升级/回HiBy），调用方应「先应答 MEOW_OK 受理，再执行」（执行后通常不返回）。 */
static int execute_action(const m_power_action_t *a, m_power_status_t *st)
{
    memset(st, 0, sizeof *st);
    st->cmd = a->cmd;
    switch (a->cmd) {
    case POWER_SHUTDOWN:
        sync();                       /* 通知转储由 launcher 先做；服务 sync() 落盘 */
        st->code = MEOW_OK;
        snprintf(st->msg, sizeof st->msg, "shutdown accepted");
        return 1;                     /* 应答后：logo + poweroff（不返回） */
    case POWER_REBOOT:
        write_boot_default(0);        /* 普通重启恒回 MeowOS（无视之前） */
        sync();
        st->code = MEOW_OK;
        snprintf(st->msg, sizeof st->msg, "reboot accepted (boot=meow)");
        return 1;
    case POWER_UPGRADE:
        sync();
        st->code = MEOW_OK;
        snprintf(st->msg, sizeof st->msg, "upgrade accepted");
        return 1;
    case POWER_BACK_HIBY:
        write_boot_default(1);
        sync();
        st->code = MEOW_OK;
        snprintf(st->msg, sizeof st->msg, "reboot -> hiby accepted");
        return 1;
    case POWER_SET_DEFAULT_MEOW:
        write_boot_default(0);
        st->code = MEOW_OK;
        snprintf(st->msg, sizeof st->msg, "boot_default=meow (next boot)");
        return 0;
    case POWER_SET_DEFAULT_HIBY:
        write_boot_default(1);
        st->code = MEOW_OK;
        snprintf(st->msg, sizeof st->msg, "boot_default=hiby (next boot)");
        return 0;
    case POWER_STATUS:
        status_fill(st->msg, sizeof st->msg);
        st->code = MEOW_OK;
        return 0;
    case POWER_BATTERY:
        battery_fill(st->msg, sizeof st->msg);
        st->code = MEOW_OK;
        return 0;
    case POWER_REBOOT_REASON:
        { int c = cold_boot_flag();
          snprintf(st->msg, sizeof st->msg, "coldboot=%s", c < 0 ? "unknown" : (c ? "shutdown" : "reboot"));
          st->code = MEOW_OK; }
        return 0;
    case POWER_UPGRADE_STATUS:
        snprintf(st->msg, sizeof st->msg, "upgrade=%s", mtd_ota_is_upgrade() ? "yes" : "no");
        st->code = MEOW_OK;
        return 0;
    case POWER_SCREEN:
        if (a->flag == 0) { screen_off(); st->code = MEOW_OK; snprintf(st->msg, sizeof st->msg, "screen off"); return 0; }
        if (a->flag == 1) { screen_on();  st->code = MEOW_OK; snprintf(st->msg, sizeof st->msg, "screen on");  return 0; }
        if (a->flag == 2) { /* timeout 秒（arg） */
            int sec = a->arg[0] ? atoi(a->arg) : -1;
            if (sec < 0 || sec > 86400) { st->code = MEOW_ERR_INVAL;
                snprintf(st->msg, sizeof st->msg, "screen timeout: bad sec"); return 0; }
            settings_set_int("display.screen_off_timeout", sec);
            st->code = MEOW_OK;
            snprintf(st->msg, sizeof st->msg, "screen_off_timeout=%ds", sec);
            return 0;
        }
        st->code = MEOW_ERR_INVAL;
        snprintf(st->msg, sizeof st->msg, "screen: bad flag");
        return 0;
    case POWER_DAC:
        { int rc = dac_cmd(a->flag == 2 ? "status" : (a->flag == 1 ? "on" : "off"),
                           st->msg, sizeof st->msg);
          st->code = rc; }
        return 0;
    default:
        st->code = MEOW_ERR_INVAL;
        snprintf(st->msg, sizeof st->msg, "unknown cmd %u", a->cmd);
        return 0;
    }
}

/* 执行「系统动作」（在应答 MEOW_OK 之后调用；通常不返回）。 */
static void run_system_action(uint32_t cmd)
{
    switch (cmd) {
    case POWER_SHUTDOWN:
        show_shutdown_logo();
        sys_reboot_do(LINUX_REBOOT_CMD_POWER_OFF);
        break;
    case POWER_REBOOT:
        sys_reboot_do(LINUX_REBOOT_CMD_RESTART);
        break;
    case POWER_UPGRADE:
        enter_upgrade();
        sys_reboot_do(LINUX_REBOOT_CMD_RESTART);
        break;
    case POWER_BACK_HIBY:
        sys_reboot_do(LINUX_REBOOT_CMD_RESTART);
        break;
    default: break;
    }
}

/* ---------------- IPC 帧读写（同 meow_ipc 客户端约定，全小端） ---------------- */
static int x_read_full(int fd, uint8_t *buf, size_t n)
{
    size_t off = 0;
    while (off < n) {
        ssize_t r = read(fd, buf + off, n - off);
        if (r <= 0) return -1;
        off += (size_t)r;
    }
    return 0;
}
static int x_write_full(int fd, const uint8_t *buf, size_t n)
{
    size_t off = 0;
    while (off < n) {
        ssize_t w = write(fd, buf + off, n - off);
        if (w <= 0) return -1;
        off += (size_t)w;
    }
    return 0;
}

static int send_frame(int fd, uint16_t type, uint32_t req_id, const void *payload, uint32_t len)
{
    uint8_t hdr[MEOW_IPC_HDR_LEN];
    uint32_t magic = MEOW_IPC_MAGIC, rlen = len;
    uint16_t ver = MEOW_IPC_VERSION, t = type;
    memcpy(hdr + 0, &magic, 4);
    memcpy(hdr + 4, &ver, 2);
    memcpy(hdr + 6, &t, 2);
    memcpy(hdr + 8, &req_id, 4);
    memcpy(hdr + 12, &rlen, 4);
    if (x_write_full(fd, hdr, MEOW_IPC_HDR_LEN) < 0) return -1;
    if (len && payload && x_write_full(fd, payload, len) < 0) return -1;
    return 0;
}

static int send_ack(int fd, uint32_t req_id, uint32_t code, uint32_t status)
{
    m_ack_t a;
    memset(&a, 0, sizeof a);
    a.code = code;
    a.status = status;
    return send_frame(fd, MSG_ACK, req_id, &a, sizeof a);
}

static int send_err(int fd, uint32_t req_id, uint32_t code, const char *msg)
{
    m_err_t e;
    memset(&e, 0, sizeof e);
    e.code = code;
    uint16_t ml = msg ? (uint16_t)strlen(msg) : 0;
    if (ml > 63) ml = 63;
    e.msg_len = ml;
    if (ml) memcpy(e.msg, msg, ml);
    return send_frame(fd, MSG_ERR, req_id, &e, sizeof e);
}

static int send_power_status(int fd, uint32_t req_id, const m_power_status_t *st)
{
    m_power_status_t s = *st;
    uint16_t ml = (uint16_t)strlen(s.msg);
    if (ml >= sizeof s.msg) ml = (uint16_t)(sizeof s.msg - 1);
    s.msg_len = ml;
    return send_frame(fd, MSG_POWER_STATUS, req_id, &s, sizeof s);
}

/* 处理单条连接（连接内循环读帧：客户端先 MSG_HELLO 握手，再 MSG_POWER_ACTION）。 */
static void handle_conn(int c)
{
    /* 基础鉴权：调用方 uid==0（root）才受理动作。 */
    struct ucred cred;
    socklen_t cl = sizeof cred;
    int uid0 = 0;
    if (getsockopt(c, SOL_SOCKET, SO_PEERCRED, &cred, &cl) == 0 && cred.uid == 0)
        uid0 = 1;

    for (;;) {
        uint8_t hdr[MEOW_IPC_HDR_LEN];
        if (x_read_full(c, hdr, sizeof hdr) < 0) break;   /* EOF/错误 */
        uint32_t magic, rlen, req_id;
        uint16_t ver, type;
        memcpy(&magic, hdr, 4);
        memcpy(&ver, hdr + 4, 2);
        memcpy(&type, hdr + 6, 2);
        memcpy(&req_id, hdr + 8, 4);
        memcpy(&rlen, hdr + 12, 4);
        if (magic != MEOW_IPC_MAGIC || ver != MEOW_IPC_VERSION) {
            send_err(c, req_id, MEOW_ERR_INVAL, "bad magic/ver"); break;
        }
        if (rlen > MEOW_IPC_MAX) {
            send_err(c, req_id, MEOW_ERR_INVAL, "payload too big"); break;
        }
        uint8_t payload[MEOW_IPC_MAX];
        if (rlen && x_read_full(c, payload, rlen) < 0) break;

        if (type == MSG_HELLO) { send_ack(c, req_id, MEOW_OK, 0); continue; }

        if (type == MSG_POWER_ACTION) {
            m_power_action_t a;
            memset(&a, 0, sizeof a);
            if (rlen > sizeof a) rlen = sizeof a;
            memcpy(&a, payload, rlen);
            if (!uid0) {
                m_power_status_t st;
                memset(&st, 0, sizeof st);
                st.code = MEOW_ERR_PERM;
                st.cmd = a.cmd;
                snprintf(st.msg, sizeof st.msg, "permission denied (uid!=0)");
                send_power_status(c, req_id, &st);
                continue;
            }
            m_power_status_t st;
            int act = execute_action(&a, &st);
            if (act == 0) { send_power_status(c, req_id, &st); continue; }
            /* 系统动作：先应答受理（客户端不阻塞），再执行（常不返回） */
            send_power_status(c, req_id, &st);
            run_system_action(a.cmd);
            break;
        }
        send_err(c, req_id, MEOW_ERR_INVAL, "unknown type");
        break;
    }
}

static int run_daemon(const char *sock)
{
    signal(SIGPIPE, SIG_IGN);
    int lfd = socket(AF_UNIX, SOCK_STREAM, 0);
    if (lfd < 0) { svc_log("socket fail: %s", strerror(errno)); return 1; }
    struct sockaddr_un a;
    memset(&a, 0, sizeof a);
    a.sun_family = AF_UNIX;
    strncpy(a.sun_path, sock, sizeof a.sun_path - 1);
    unlink(sock);
    if (bind(lfd, (struct sockaddr *)&a, sizeof a) < 0) {
        svc_log("bind %s fail: %s", sock, strerror(errno));
        close(lfd);
        return 1;
    }
    chmod(sock, 0666);
    if (listen(lfd, 8) < 0) { svc_log("listen fail: %s", strerror(errno)); close(lfd); return 1; }
    svc_log("meow_svc_power listening on %s", sock);
    for (;;) {
        int c = accept(lfd, NULL, NULL);
        if (c < 0) { if (errno == EINTR) continue; continue; }
        handle_conn(c);
        close(c);
    }
    return 0;
}

/* ---------------- CLI ---------------- */
static int cli_run(int n, char **v)
{
    const char *cmd = v[0];
    if (!strcmp(cmd, "shutdown")) {
        show_shutdown_logo();
        sys_reboot_do(LINUX_REBOOT_CMD_POWER_OFF);
        return 0;                                   /* 不返回 */
    }
    if (!strcmp(cmd, "reboot")) {
        if (n > 1 && !strcmp(v[1], "--hiby")) { write_boot_default(1); }
        else write_boot_default(0);                 /* 普通重启恒回 MeowOS */
        sys_reboot_do(LINUX_REBOOT_CMD_RESTART);
        return 0;
    }
    if (!strcmp(cmd, "upgrade")) {
        enter_upgrade();
        sys_reboot_do(LINUX_REBOOT_CMD_RESTART);
        return 0;
    }
    if (!strcmp(cmd, "set-default-hiby")) {
        write_boot_default(1);
        printf("boot_default=hiby (next boot)\n");
        return 0;
    }
    if (!strcmp(cmd, "set-default-meow")) {
        write_boot_default(0);
        printf("boot_default=meow (next boot)\n");
        return 0;
    }
    if (!strcmp(cmd, "status")) {
        char out[128];
        status_fill(out, sizeof out);
        printf("%s\n", out);
        return 0;
    }
    if (!strcmp(cmd, "battery")) {
        char out[64];
        battery_fill(out, sizeof out);
        printf("%s\n", out);
        return 0;
    }
    if (!strcmp(cmd, "reboot-reason")) {
        int c = cold_boot_flag();
        printf("coldboot=%s\n", c < 0 ? "unknown" : (c ? "shutdown" : "reboot"));
        return 0;
    }
    if (!strcmp(cmd, "upgrade-status")) {
        printf("upgrade=%s\n", mtd_ota_is_upgrade() ? "yes" : "no");
        return 0;
    }
    if (!strcmp(cmd, "screen")) {
        if (n < 2) { fprintf(stderr, "screen needs on|off|timeout<秒>\n"); return 1; }
        if (!strcmp(v[1], "on")) return screen_on();
        if (!strcmp(v[1], "off")) return screen_off();
        if (!strcmp(v[1], "timeout")) {
            if (n < 3) { fprintf(stderr, "screen timeout needs <秒>\n"); return 1; }
            int sec = atoi(v[2]);
            if (sec < 0 || sec > 86400) { fprintf(stderr, "screen timeout: bad sec\n"); return 1; }
            settings_set_int("display.screen_off_timeout", sec);
            printf("screen_off_timeout=%ds\n", sec);
            return 0;
        }
        fprintf(stderr, "screen: bad sub %s\n", v[1]);
        return 1;
    }
    if (!strcmp(cmd, "dac")) {
        if (n < 2) { fprintf(stderr, "dac needs on|off|status\n"); return 1; }
        char out[160];
        int rc = dac_cmd(v[1], out, sizeof out);
        printf("%s\n", out);
        return rc == MEOW_OK ? 0 : 1;
    }
    fprintf(stderr, "usage: meow_svc_power <cmd>  (%s)\n", cli_usage());
    return 1;
}

static const char *cli_usage(void)
{
    return "shutdown|reboot[--hiby]|upgrade|set-default-hiby|set-default-meow|"
           "status|battery|reboot-reason|upgrade-status|screen on|off|timeout<秒>|dac on|off|status";
}

int main(int argc, char **argv)
{
    const char *env = getenv("MEOW_IPC_POWER_SOCK");
    if (env && env[0]) g_sock = env;

    int i = 1;
    for (; i < argc; i++) {
        if (!strcmp(argv[i], "--sock") && i + 1 < argc) g_sock = argv[++i];
        else if (!strcmp(argv[i], "-h") || !strcmp(argv[i], "--help")) {
            printf("meow_svc_power (%s)\n", cli_usage());
            return 0;
        }
        else break;
    }
    if (i >= argc) return run_daemon(g_sock);   /* svcd 空参 → IPC 常驻 */
    return cli_run(argc - i, argv + i);
}