Possible? Android Permission Request Concurrency Issue

user_18423398 0
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Is there a possibility that the below code could fail due to the user denying the SCHEDULE_EXACT_ALARM permission after the permissions check and before the alarm is scheduled?

Note: I have never experienced this issue, this is purely an academic excersize.

public class MyService extends Service {

    private void scheduleExactAlarm(Calendar alarmCalendar) {

        if(getApplicationContext().checkSelfPermission(Manifest.permission.SCHEDULE_EXACT_ALARM) != PackageManager.PERMISSION_GRANTED) {
            // handle permission not granted
            return;
        }

        // can the user deny the permission here?

        AlarmManager.AlarmClockInfo alarmInfo = // create alarmInfo with desired information
        PendingIntent alarmOperation = // create alarmOperation with desired intent    
        AlarmManager alarmManager = getSystemService(AlarmManager.class);    
        alarmManager.setAlarmClock(alarmInfo, alarmOperation);
    }
    
    // the rest of the service implementation...

}

EDIT: I learned something new today. Special Permissions are not part of runtime permissions, so using checkSelfPermission(SCHEDULE_EXACT_ALARM) doesn't make sense. That being said, the question is intended to be broader than the specific permissions/operations used.

android java
2 Answers

No, it is not possible. Android will terminate your process if Android revokes a permission for any reason (user revoked it in Settings, auto-revocation due to lack of app use on Android 12+, etc.).

That being said, Ian Lake's comment is also valid: checkSelfPermission(Manifest.permission.SCHEDULE_EXACT_ALARM) should never return PERMISSION_GRANTED is not going to work well. While your concern is valid for dangerous permissions, based on current 13 DP1 behavior, SCHEDULE_EXACT_ALARM is not categorized as dangerous and is not part of the runtime permission system.

user_1151450

Theoretically? Sure, if the OS decided to task switch taking the processor away from the app, and the user denied permission before it task switched back. Practically? No, task switches happen many times a second, there's no way it wouldn't get a time slice before a user would do that.

user_16311930
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