3 files changed, 68 insertions, 3 deletions

diff --git a/core/java/android/content/pm/ApplicationInfo.java b/core/java/android/content/pm/ApplicationInfo.java
index 068a93a253ff..5328dda03893 100644
--- a/core/java/android/content/pm/ApplicationInfo.java
+++ b/core/java/android/content/pm/ApplicationInfo.java
@@ -678,6 +678,14 @@ public class ApplicationInfo extends PackageItemInfo implements Parcelable {
      */
     public static final int PRIVATE_FLAG_IS_RESOURCE_OVERLAY = 1 << 28;
 
+    /**
+     * Value for {@link #privateFlags}: If {@code true} this app allows
+     * shared/external storage media to be a sandboxed view that only contains
+     * files owned by the app.
+     *
+     * @hide
+     */
+    public static final int PRIVATE_FLAG_ALLOW_EXTERNAL_STORAGE_SANDBOX = 1 << 29;
 
     /** @hide */
     @IntDef(flag = true, prefix = { "PRIVATE_FLAG_" }, value = {
@@ -707,7 +715,8 @@ public class ApplicationInfo extends PackageItemInfo implements Parcelable {
             PRIVATE_FLAG_VIRTUAL_PRELOAD,
             PRIVATE_FLAG_HAS_FRAGILE_USER_DATA,
             PRIVATE_FLAG_ALLOW_CLEAR_USER_DATA_ON_FAILED_RESTORE,
-            PRIVATE_FLAG_ALLOW_AUDIO_PLAYBACK_CAPTURE
+            PRIVATE_FLAG_ALLOW_AUDIO_PLAYBACK_CAPTURE,
+            PRIVATE_FLAG_ALLOW_EXTERNAL_STORAGE_SANDBOX,
     })
     @Retention(RetentionPolicy.SOURCE)
     public @interface ApplicationInfoPrivateFlags {}
@@ -1822,6 +1831,16 @@ public class ApplicationInfo extends PackageItemInfo implements Parcelable {
         return (privateFlags & PRIVATE_FLAG_ALLOW_AUDIO_PLAYBACK_CAPTURE) != 0;
     }
 
+    /**
+     * If {@code true} this app allows shared/external storage media to be a
+     * sandboxed view that only contains files owned by the app.
+     *
+     * @hide
+     */
+    public boolean isExternalStorageSandboxAllowed() {
+        return (privateFlags & PRIVATE_FLAG_ALLOW_EXTERNAL_STORAGE_SANDBOX) != 0;
+    }
+
     private boolean isAllowedToUseHiddenApis() {
         if (isSignedWithPlatformKey()) {
             return true;
diff --git a/core/java/android/content/pm/PackageParser.java b/core/java/android/content/pm/PackageParser.java
index 35d1eac5c0ad..0a01dcda8bbb 100644
--- a/core/java/android/content/pm/PackageParser.java
+++ b/core/java/android/content/pm/PackageParser.java
@@ -3689,6 +3689,12 @@ public class PackageParser {
             ai.privateFlags |= ApplicationInfo.PRIVATE_FLAG_ALLOW_AUDIO_PLAYBACK_CAPTURE;
         }
 
+        if (sa.getBoolean(
+                R.styleable.AndroidManifestApplication_allowExternalStorageSandbox,
+                owner.applicationInfo.targetSdkVersion >= Build.VERSION_CODES.Q)) {
+            ai.privateFlags |= ApplicationInfo.PRIVATE_FLAG_ALLOW_EXTERNAL_STORAGE_SANDBOX;
+        }
+
         ai.maxAspectRatio = sa.getFloat(R.styleable.AndroidManifestApplication_maxAspectRatio, 0);
         ai.minAspectRatio = sa.getFloat(R.styleable.AndroidManifestApplication_minAspectRatio, 0);
 
diff --git a/core/java/android/os/Environment.java b/core/java/android/os/Environment.java
index cceb6edc4c0a..f7e927e48863 100644
--- a/core/java/android/os/Environment.java
+++ b/core/java/android/os/Environment.java
@@ -20,6 +20,8 @@ import android.annotation.NonNull;
 import android.annotation.SystemApi;
 import android.annotation.TestApi;
 import android.annotation.UnsupportedAppUsage;
+import android.app.AppGlobals;
+import android.app.AppOpsManager;
 import android.app.admin.DevicePolicyManager;
 import android.content.Context;
 import android.os.storage.StorageManager;
@@ -1060,7 +1062,7 @@ public class Environment {
      * @throws IllegalArgumentException if the path is not a valid storage
      *             device.
      */
-    public static boolean isExternalStorageRemovable(File path) {
+    public static boolean isExternalStorageRemovable(@NonNull File path) {
         final StorageVolume volume = StorageManager.getStorageVolume(path, UserHandle.myUserId());
         if (volume != null) {
             return volume.isRemovable();
@@ -1103,7 +1105,7 @@ public class Environment {
      * @throws IllegalArgumentException if the path is not a valid storage
      *             device.
      */
-    public static boolean isExternalStorageEmulated(File path) {
+    public static boolean isExternalStorageEmulated(@NonNull File path) {
         final StorageVolume volume = StorageManager.getStorageVolume(path, UserHandle.myUserId());
         if (volume != null) {
             return volume.isEmulated();
@@ -1112,6 +1114,44 @@ public class Environment {
         }
     }
 
+    /**
+     * Returns whether the shared/external storage media at the given path is a
+     * sandboxed view that only contains files owned by the app.
+     * <p>
+     * This value may be different from the value requested by
+     * {@code allowExternalStorageSandbox} in the app's manifest, since an app
+     * may inherit its sandboxed state based on when it was first installed.
+     * <p>
+     * Sandboxed apps can continue to discover and read media belonging to other
+     * apps via {@link android.provider.MediaStore}.
+     */
+    public static boolean isExternalStorageSandboxed() {
+        final File externalDir = sCurrentUser.getExternalDirs()[0];
+        return isExternalStorageSandboxed(externalDir);
+    }
+
+    /**
+     * Returns whether the shared/external storage media at the given path is a
+     * sandboxed view that only contains files owned by the app.
+     * <p>
+     * This value may be different from the value requested by
+     * {@code allowExternalStorageSandbox} in the app's manifest, since an app
+     * may inherit its sandboxed state based on when it was first installed.
+     * <p>
+     * Sandboxed apps can continue to discover and read media belonging to other
+     * apps via {@link android.provider.MediaStore}.
+     *
+     * @throws IllegalArgumentException if the path is not a valid storage
+     *             device.
+     */
+    public static boolean isExternalStorageSandboxed(@NonNull File path) {
+        final Context context = AppGlobals.getInitialApplication();
+        final AppOpsManager appOps = context.getSystemService(AppOpsManager.class);
+        return appOps.noteOpNoThrow(AppOpsManager.OP_LEGACY_STORAGE,
+                context.getApplicationInfo().uid,
+                context.getPackageName()) != AppOpsManager.MODE_ALLOWED;
+    }
+
     static File getDirectory(String variableName, String defaultPath) {
         String path = System.getenv(variableName);
         return path == null ? new File(defaultPath) : new File(path);