remove URI permissions for obsolete paths

android/app/build.gradle

@@ -105,7 +105,7 @@ repositories {
 
 dependencies {
     implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.3.9'
-    implementation 'androidx.core:core-ktx:1.5.0'
+    implementation 'androidx.core:core-ktx:1.6.0'
     implementation 'androidx.exifinterface:exifinterface:1.3.2'
     implementation 'androidx.multidex:multidex:2.0.1'
     implementation 'com.caverock:androidsvg-aar:1.4'

android/app/src/main/kotlin/deckers/thibault/aves/utils/PermissionManager.kt

@@ -133,8 +133,7 @@ object PermissionManager {
     @RequiresApi(Build.VERSION_CODES.LOLLIPOP)
     fun revokeDirectoryAccess(context: Context, path: String): Boolean {
         return StorageUtils.convertDirPathToTreeUri(context, path)?.let {
-            val flags = Intent.FLAG_GRANT_READ_URI_PERMISSION or Intent.FLAG_GRANT_WRITE_URI_PERMISSION
+            releaseUriPermission(context, it)
-            context.contentResolver.releasePersistableUriPermission(it, flags)
             true
         } ?: false
     }
@@ -158,4 +157,28 @@ object PermissionManager {
         }
         return accessibleDirs
     }
+
+    // As of Android R, `MediaStore.getDocumentUri` fails if any of the persisted
+    // URI permissions we hold points to a folder that no longer exists,
+    // so we should remove these obsolete URIs before proceeding.
+    @RequiresApi(Build.VERSION_CODES.LOLLIPOP)
+    fun sanitizePersistedUriPermissions(context: Context) {
+        try {
+            for (uriPermission in context.contentResolver.persistedUriPermissions) {
+                val uri = uriPermission.uri
+                val path = StorageUtils.convertTreeUriToDirPath(context, uri)
+                if (path != null && !File(path).exists()) {
+                    Log.d(LOG_TAG, "revoke URI permission for obsolete path=$path")
+                    releaseUriPermission(context, uri)
+                }
+            }
+        } catch (e: Exception) {
+            Log.w(LOG_TAG, "failed to sanitize persisted URI permissions", e)
+        }
+    }
+
+    private fun releaseUriPermission(context: Context, it: Uri) {
+        val flags = Intent.FLAG_GRANT_READ_URI_PERMISSION or Intent.FLAG_GRANT_WRITE_URI_PERMISSION
+        context.contentResolver.releasePersistableUriPermission(it, flags)
+    }
 }

android/app/src/main/kotlin/deckers/thibault/aves/utils/StorageUtils.kt

@@ -293,6 +293,7 @@ object StorageUtils {
                 // need a document URI (not a media content URI) to open a `DocumentFile` output stream
                 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O && isMediaStoreContentUri(mediaUri)) {
                     // cleanest API to get it
+                    PermissionManager.sanitizePersistedUriPermissions(context)
                     try {
                         val docUri = MediaStore.getDocumentUri(context, mediaUri)
                         if (docUri != null) {

android/build.gradle

@@ -6,7 +6,7 @@ buildscript {
         mavenCentral()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:4.2.1'
+        classpath 'com.android.tools.build:gradle:4.2.2'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
         classpath 'com.google.gms:google-services:4.3.8'
         classpath 'com.google.firebase:firebase-crashlytics-gradle:2.7.1'