鸿蒙OS投票机制

码农中的小白2024-10-11 20:19

(基于openharmony5.0)

投票机制

param get | grep ohos.boot.time
图投票机制参数图

只有当所有的投票完成，开机动画才会退出，整理需要投票的系统应用（三方应用不参与投票）如下图所示：

以进程foundation为例：

foundation\systemabilitymgr\safwk\etc\profile\foundation.cfg

"bootevents": [
    "bootevent.wms.fullscreen.ready",
    "bootevent.appfwk.ready",
    "bootevent.lockscreen.ready",
    "bootevent.wms.ready"
],

可以看到foundation进程有4个投票事件，会在相应的时机，代码中调用SystemWriteParam()方法进行投票。如果有需要投票的地方没有投，会导致开机动画不会退出，开机动画退出会检测bootevent.boot.completed事件。

base\startup\init\services\modules\bootevent\bootevent.c

#define BOOT_EVENT_BOOT_COMPLETED "bootevent.boot.completed"

...

static int BootEventParaFireByName(const char *paramName)
{
    BOOT_EVENT_PARAM_ITEM *found = NULL;

    char *bootEventValue = strrchr(paramName, '.');
    INIT_CHECK(bootEventValue != NULL, return 0);
    bootEventValue[0] = '\0';

    WriteBooteventSysParam(paramName);

    found = (BOOT_EVENT_PARAM_ITEM *)OH_ListFind(&bootEventList, (void *)paramName, BootEventParaListCompareProc);
    if (found == NULL) {
        return 0;
    }

    // Already fired
    if (found->timestamp[BOOTEVENT_READY].tv_sec > 0) {
        return 0;
    }
    INIT_CHECK_RETURN_VALUE(clock_gettime(CLOCK_MONOTONIC,
        &(found->timestamp[BOOTEVENT_READY])) == 0, 0);

    g_bootEventNum--;
    SetServiceBooteventHookMgr(NULL, paramName, 2); // 2: bootevent service has ready
    // Check if all boot event params are fired
    if (g_bootEventNum > 0) {
        return 0;
    }
    // All parameters are fired, set boot completed now ...
    INIT_LOGI("All boot events are fired, boot complete now ...");
    //所有投票事件都已经完成
    SystemWriteParam(BOOT_EVENT_BOOT_COMPLETED, "true");
    SaveServiceBootEvent();
    // report complete event
    ReportSysEvent();
    BootCompleteClearAll();
#ifndef STARTUP_INIT_TEST
    HookMgrExecute(GetBootStageHookMgr(), INIT_BOOT_COMPLETE, NULL, NULL);
#endif
    RemoveCmdExecutor("bootevent", -1);
    return 1;
}