android系統,按住MENU鍵開機,會安全模式進入系統。
代碼位置:
frameworks/policies/base/phone/com/android/internal/policy/impl/PhoneWindowManager.java
收索SAFE MODE 這個tag會看到相關代碼。
步驟:在開機動畫時,按住MENU鍵(或者字母S鍵,方向鍵的中間鍵,鼠標左鍵中的一個)直到開機,會進入安全模式。
得到log如下:
I/WindowManager( 101): SAFE MODE ENABLED (menu=1 s=-1 dpad=-1 trackball=-1)
現象:在機器左小腳顯示“安全模式”。
Android5.1:
frameworks/base/services/core/java/com/android/server/wm/WindowManagerService.java
public boolean detectSafeMode() {
if (!mInputMonitor.waitForInputDevicesReady(
INPUT_DEVICES_READY_FOR_SAFE_MODE_DETECTION_TIMEOUT_MILLIS)) {
Slog.w(TAG, "Devices still not ready after waiting "
+ INPUT_DEVICES_READY_FOR_SAFE_MODE_DETECTION_TIMEOUT_MILLIS
+ " milliseconds before attempting to detect safe mode.");
}
int menuState = mInputManager.getKeyCodeState(-1, InputDevice.SOURCE_ANY,
KeyEvent.KEYCODE_MENU);
int sState = mInputManager.getKeyCodeState(-1, InputDevice.SOURCE_ANY, KeyEvent.KEYCODE_S);
int dpadState = mInputManager.getKeyCodeState(-1, InputDevice.SOURCE_DPAD,
KeyEvent.KEYCODE_DPAD_CENTER);
int trackballState = mInputManager.getScanCodeState(-1, InputDevice.SOURCE_TRACKBALL,
InputManagerService.BTN_MOUSE);
int volumeDownState = mInputManager.getKeyCodeState(-1, InputDevice.SOURCE_ANY,
KeyEvent.KEYCODE_VOLUME_DOWN);
mSafeMode = menuState > 0 || sState > 0 || dpadState > 0 || trackballState > 0
|| volumeDownState > 0;
try {
if (SystemProperties.getInt(ShutdownThread.REBOOT_SAFEMODE_PROPERTY, 0) != 0) {
mSafeMode = true;
SystemProperties.set(ShutdownThread.REBOOT_SAFEMODE_PROPERTY, "");
}
} catch (IllegalArgumentException e) {
}
if (mSafeMode) {
Log.i(TAG, "SAFE MODE ENABLED (menu=" + menuState + " s=" + sState
+ " dpad=" + dpadState + " trackball=" + trackballState + ")");
} else {
Log.i(TAG, "SAFE MODE not enabled");
}
mPolicy.setSafeMode(mSafeMode);
return mSafeMode;
}
要把safe mode禁止掉,把mSafeMode賦值為false即可。