fixup! Allow secondary user backup to USB

Issue: calyxos#1058
Change-Id: I4aaadef5954e9c091f7048bffd8e0ed700fdd2e6

app/src/main/java/com/stevesoltys/seedvault/App.kt

@@ -5,12 +5,11 @@ import android.app.Application
 import android.app.backup.BackupManager.PACKAGE_MANAGER_SENTINEL
 import android.app.backup.IBackupManager
 import android.content.Context
-import android.content.Context.BACKUP_SERVICE
 import android.content.pm.PackageManager.PERMISSION_GRANTED
 import android.os.Build
 import android.os.ServiceManager.getService
 import android.os.StrictMode
-import android.os.UserHandle
+import android.os.UserManager
 import com.stevesoltys.seedvault.crypto.cryptoModule
 import com.stevesoltys.seedvault.header.headerModule
 import com.stevesoltys.seedvault.metadata.MetadataManager
@@ -143,8 +142,11 @@ fun <T> permitDiskReads(func: () -> T): T {
     }
 }
 
-fun Context.getSystemContext(isUsbStorage: () -> Boolean): Context {
+@Suppress("MissingPermission")
-    return if (checkSelfPermission(INTERACT_ACROSS_USERS_FULL) == PERMISSION_GRANTED &&
+fun Context.getStorageContext(isUsbStorage: () -> Boolean): Context {
-        isUsbStorage()
+    if (checkSelfPermission(INTERACT_ACROSS_USERS_FULL) == PERMISSION_GRANTED && isUsbStorage()) {
-    ) createContextAsUser(UserHandle.SYSTEM, 0) else this
+        UserManager.get(this).getProfileParent(user)
+            ?.let { parent -> return createContextAsUser(parent, 0) }
+    }
+    return this
 }

app/src/main/java/com/stevesoltys/seedvault/plugins/saf/DocumentsProviderStoragePlugin.kt

@@ -4,7 +4,7 @@ import android.content.Context
 import android.content.pm.PackageManager
 import android.util.Log
 import androidx.documentfile.provider.DocumentFile
-import com.stevesoltys.seedvault.getSystemContext
+import com.stevesoltys.seedvault.getStorageContext
 import com.stevesoltys.seedvault.plugins.EncryptedMetadata
 import com.stevesoltys.seedvault.plugins.StoragePlugin
 import com.stevesoltys.seedvault.settings.Storage
@@ -25,7 +25,7 @@ internal class DocumentsProviderStoragePlugin(
      * Attention: This context might be from a different user. Use with care.
      */
     private val context: Context
-        get() = appContext.getSystemContext {
+        get() = appContext.getStorageContext {
             storage.storage?.isUsb == true
         }
 
@@ -83,7 +83,7 @@ internal class DocumentsProviderStoragePlugin(
     @Throws(IOException::class)
     override suspend fun hasBackup(storage: Storage): Boolean {
         // potentially get system user context if needed here
-        val c = appContext.getSystemContext { storage.isUsb }
+        val c = appContext.getStorageContext { storage.isUsb }
         val parent = DocumentFile.fromTreeUri(c, storage.uri) ?: throw AssertionError()
         val rootDir = parent.findFileBlocking(c, DIRECTORY_ROOT) ?: return false
         val backupSets = getBackups(c, rootDir)

app/src/main/java/com/stevesoltys/seedvault/plugins/saf/DocumentsStorage.kt

@@ -16,7 +16,7 @@ import android.provider.DocumentsContract.getDocumentId
 import android.util.Log
 import androidx.annotation.VisibleForTesting
 import androidx.documentfile.provider.DocumentFile
-import com.stevesoltys.seedvault.getSystemContext
+import com.stevesoltys.seedvault.getStorageContext
 import com.stevesoltys.seedvault.settings.SettingsManager
 import com.stevesoltys.seedvault.settings.Storage
 import kotlinx.coroutines.TimeoutCancellationException
@@ -55,7 +55,7 @@ internal class DocumentsStorage(
      * Attention: This context might be from a different user. Use with care.
      */
     private val context: Context
-        get() = appContext.getSystemContext {
+        get() = appContext.getStorageContext {
             storage?.isUsb == true
         }
     private val contentResolver: ContentResolver get() = context.contentResolver

app/src/main/java/com/stevesoltys/seedvault/settings/SettingsManager.kt

@@ -9,7 +9,7 @@ import androidx.annotation.UiThread
 import androidx.annotation.WorkerThread
 import androidx.documentfile.provider.DocumentFile
 import androidx.preference.PreferenceManager
-import com.stevesoltys.seedvault.getSystemContext
+import com.stevesoltys.seedvault.getStorageContext
 import com.stevesoltys.seedvault.permitDiskReads
 import com.stevesoltys.seedvault.transport.backup.BackupCoordinator
 import java.util.concurrent.ConcurrentSkipListSet
@@ -131,7 +131,7 @@ class SettingsManager(private val context: Context) {
     @WorkerThread
     fun canDoBackupNow(): Boolean {
         val storage = getStorage() ?: return false
-        val systemContext = context.getSystemContext { storage.isUsb }
+        val systemContext = context.getStorageContext { storage.isUsb }
         return !storage.isUnavailableUsb(systemContext) && !storage.isUnavailableNetwork(context)
     }
 

app/src/main/java/com/stevesoltys/seedvault/storage/SeedvaultStoragePlugin.kt

@@ -3,7 +3,7 @@ package com.stevesoltys.seedvault.storage
 import android.content.Context
 import androidx.documentfile.provider.DocumentFile
 import com.stevesoltys.seedvault.crypto.KeyManager
-import com.stevesoltys.seedvault.getSystemContext
+import com.stevesoltys.seedvault.getStorageContext
 import com.stevesoltys.seedvault.plugins.saf.DocumentsStorage
 import org.calyxos.backup.storage.plugin.saf.SafStoragePlugin
 import javax.crypto.SecretKey
@@ -17,7 +17,7 @@ internal class SeedvaultStoragePlugin(
      * Attention: This context might be from a different user. Use with care.
      */
     override val context: Context
-        get() = appContext.getSystemContext {
+        get() = appContext.getStorageContext {
             storage.storage?.isUsb == true
         }
     override val root: DocumentFile

app/src/main/java/com/stevesoltys/seedvault/ui/storage/StorageRootResolver.kt

@@ -20,7 +20,7 @@ import android.provider.DocumentsContract.Root.FLAG_SUPPORTS_CREATE
 import android.provider.DocumentsContract.Root.FLAG_SUPPORTS_IS_CHILD
 import android.util.Log
 import com.stevesoltys.seedvault.R
-import com.stevesoltys.seedvault.getSystemContext
+import com.stevesoltys.seedvault.getStorageContext
 import com.stevesoltys.seedvault.ui.storage.StorageOption.SafOption
 
 internal object StorageRootResolver {
@@ -39,7 +39,7 @@ internal object StorageRootResolver {
                 }
             }
             // add special system user roots for USB devices
-            val c = context.getSystemContext {
+            val c = context.getStorageContext {
                 authority == AUTHORITY_STORAGE && UserHandle.myUserId() != UserHandle.USER_SYSTEM
             }
             // only proceed if we really got a different [Context], e.g. had permission for it