Implement cross-directory SAF rename operations

* java/org/gnu/emacs/EmacsService.java (renameDocument): Don't
catch UnsupportedOperationException; handle ENOSYS in
android_saf_rename_document instead.
(moveDocument): New function.
* lisp/subr.el (y-or-n-p): Always change the text conversion
style.
* src/android.c (android_init_emacs_service)
(android_exception_check_4): New function.
* src/android.h: Update Java function table.
* src/androidvfs.c (android_saf_rename_document): Handle ENOSYS
here by setting errno to EXDEV.
(android_saf_move_document): New function.
(android_document_id_from_name): Take const `dir_name'.
(android_saf_tree_rename): Use delete-move-rename to implement
cross-directory renames.

1 files changed, 50 insertions, 17 deletions

diff --git a/java/org/gnu/emacs/EmacsService.java b/java/org/gnu/emacs/EmacsService.java
index 07e585ad37c..e714f75fdf2 100644
--- a/java/org/gnu/emacs/EmacsService.java
+++ b/java/org/gnu/emacs/EmacsService.java
@@ -1713,26 +1713,59 @@ public final class EmacsService extends Service
     tree = Uri.parse (uri);
     uriObject = DocumentsContract.buildDocumentUriUsingTree (tree, docId);
 
-    try
-      {
-        if (DocumentsContract.renameDocument (resolver, uriObject,
-                                              name)
-            != null)
-          {
-            /* Invalidate the cache.  */
-            if (storageThread != null)
-              storageThread.postInvalidateCacheDir (tree, docId,
-                                                    name);
-            return 0;
-          }
-      }
-    catch (UnsupportedOperationException e)
+    if (DocumentsContract.renameDocument (resolver, uriObject,
+                                          name)
+        != null)
       {
-        ;;
+        /* Invalidate the cache.  */
+        if (storageThread != null)
+          storageThread.postInvalidateCacheDir (tree, docId,
+                                                name);
+        return 0;
       }
 
-    /* Handle unsupported operation exceptions specially, so
-       `android_rename' can return ENXDEV.  */
+    /* Handle errors specially, so `android_saf_rename_document' can
+       return ENXDEV.  */
     return -1;
   }
+
+  /* Move the document designated by DOCID from the directory under
+     DIR_NAME designated by SRCID to the directory designated by
+     DSTID.  If the ID of the document being moved changes as a
+     consequence of the movement, return the new ID, else NULL.
+
+     URI is the document tree containing all three documents.  */
+
+  public String
+  moveDocument (String uri, String docId, String dirName,
+                String dstId, String srcId)
+    throws FileNotFoundException
+  {
+    Uri uri1, docId1, dstId1, srcId1;
+    Uri name;
+
+    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.N)
+      throw new UnsupportedOperationException ("Documents aren't capable"
+                                               + " of being moved on Android"
+                                               + " versions before 7.0.");
+
+    uri1 = Uri.parse (uri);
+    docId1 = DocumentsContract.buildDocumentUriUsingTree (uri1, docId);
+    dstId1 = DocumentsContract.buildDocumentUriUsingTree (uri1, dstId);
+    srcId1 = DocumentsContract.buildDocumentUriUsingTree (uri1, srcId);
+
+    /* Move the document; this function returns the new ID of the
+       document should it change.  */
+    name = DocumentsContract.moveDocument (resolver, docId1,
+                                           srcId1, dstId1);
+
+    /* Now invalidate the caches for both DIRNAME and DOCID.  */
+
+    if (storageThread != null)
+      storageThread.postInvalidateCacheDir (uri1, docId, dirName);
+
+    return (name != null
+            ? DocumentsContract.getDocumentId (name)
+            : null);
+  }
 };