Writes to disk on main thread

[EGecius]

Android's Strict mode detected a disk write with the following stack trace:

05-12 07:48:03.093    9989-9989/? D/StrictMode﹕ StrictMode policy violation; ~duration=98 ms: android.os.StrictMode$StrictModeDiskWriteViolation: policy=341 violation=1
            at android.os.StrictMode$AndroidBlockGuardPolicy.onWriteToDisk(StrictMode.java:1111)
            at libcore.io.BlockGuardOs.mkdir(BlockGuardOs.java:172)
            at java.io.File.mkdirErrno(File.java:874)
            at java.io.File.mkdirs(File.java:898)
            at java.io.File.mkdirs(File.java:892)
            at com.android.server.pm.Settings.writePackageRestrictionsLPr(Settings.java:1277)
            at com.android.server.pm.PackageManagerService.setEnabledSetting(PackageManagerService.java:12201)
            at com.android.server.pm.PackageManagerService.setComponentEnabledSetting(PackageManagerService.java:12109)
            at android.content.pm.IPackageManager$Stub.onTransact(IPackageManager.java:1219)
            at com.android.server.pm.PackageManagerService.onTransact(PackageManagerService.java:1862)
            at android.os.Binder.execTransact(Binder.java:446)
    # via Binder call with stack:
    android.os.StrictMode$LogStackTrace
            at android.os.StrictMode.readAndHandleBinderCallViolations(StrictMode.java:1717)
            at android.os.Parcel.readExceptionCode(Parcel.java:1527)
            at android.os.Parcel.readException(Parcel.java:1496)
            at android.content.pm.IPackageManager$Stub$Proxy.setComponentEnabledSetting(IPackageManager.java:3394)
            at android.app.ApplicationPackageManager.setComponentEnabledSetting(ApplicationPackageManager.java:1489)
            at com.squareup.leakcanary.LeakCanary.setEnabled(LeakCanary.java:195)
            at com.squareup.leakcanary.LeakCanary.enableDisplayLeakActivity(LeakCanary.java:75)
            at com.squareup.leakcanary.LeakCanary.install(LeakCanary.java:55)
            at com.squareup.leakcanary.LeakCanary.install(LeakCanary.java:43)
            at various.App.onCreate(App.java:44)
            at android.app.Instrumentation.callApplicationOnCreate(Instrumentation.java:1012)
            at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4553)
            at android.app.ActivityThread.access$1500(ActivityThread.java:151)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1364)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:135)
            at android.app.ActivityThread.main(ActivityThread.java:5254)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)

[pyricau]

Duplicates #15 , although different. Wow so we can't call ApplicationPackageManager.setComponentEnabledSetting().

[pepyakin]

But what can we do with it? If I get it right, violation happens in another process?

[pyricau]

Stacktrace wasn't formatted so I didn't read through it. I edited, now it's better.

This is very interesting. If you do an IPC call (which is blocking) on the main thread and then the other process reads the file system, then strict mode complains. Smarts. And sort of makes sense.

What we can do is the same thing as we'd do with a normal strict mode violation: do all the setEnabled() calls asynchronously. Hopefully we won't have a leak before all the setEnabled() calls finish.

[pepyakin]

@pyricau Hm, I thought we can call setEnabled() only on main thread.