Update Android port

* INSTALL.android: Explain where to get tree-sitter.

* configure.ac: Add support for dynamic modules and tree-sitter.

* doc/emacs/android.texi (Android Windowing):
* java/org/gnu/emacs/EmacsSdk11Clipboard.java
(EmacsSdk11Clipboard, ownsClipboard): Improve clipboard handling
and documentation.

INSTALL.android

@@ -213,6 +213,8 @@ Android systems:
     (Please see the section GNUTLS near the end of this file.)
   libtiff    	- https://sourceforge.net/projects/android-ports-for-gnu-emacs
     (Extract and point ``--with-ndk-path'' to tiff-4.5.0-emacs.tar.gz.)
+  tree-sitter	- https://sourceforge.net/projects/android-ports-for-gnu-emacs
+    (Please see the section TREE-SITTER near the end of this file.)
 
 We anticipate that most untested non-trivial ndk-build dependencies
 will need adjustments in Emacs to work, as the Emacs build system
@@ -575,6 +577,16 @@ and add the resulting folders to ``--with-ndk-path''.  Note that you
 should not try to build these packages separately using any
 `configure' script or Makefiles inside.
 
+TREE-SITTER
+
+A copy of tree-sitter modified to build with the ndk-build system can
+also find that URL.  To build Emacs with tree-sitter, you must unpack
+the following tar archive in that site:
+
+  tree-sitter-0.20.7-emacs.tar.gz
+
+and add the resulting folder to ``--with-ndk-build''.
+
 
 
 This file is part of GNU Emacs.

configure.ac

@@ -1074,6 +1074,8 @@ package will likely install on older systems but crash on startup.])
   passthrough="$passthrough --with-gnutls=$with_gnutls"
   passthrough="$passthrough --with-tiff=$with_tiff"
   passthrough="$passthrough --with-selinux=$with_selinux"
+  passthrough="$passthrough --with-modules=$with_modules"
+  passthrough="$passthrough --with-tree-sitter=$with_tree_sitter"
 
   AS_IF([XCONFIGURE=android ANDROID_CC="$ANDROID_CC" \
          ANDROID_SDK="$android_sdk" android_abi=$android_abi \
@@ -1146,6 +1148,8 @@ if test "$ANDROID" = "yes"; then
     with_gnutls=no
     with_tiff=no
     with_selinux=no
+    with_modules=no
+    with_tree_sitter=no
   fi
 
   with_rsvg=no
@@ -1153,14 +1157,12 @@ if test "$ANDROID" = "yes"; then
   with_libsystemd=no
   with_cairo=no
   with_imagemagick=no
-  with_tree_sitter=no
   with_xft=no
   with_harfbuzz=no
   with_libotf=no
   with_gpm=no
   with_dbus=no
   with_gsettings=no
-  with_modules=no
   with_threads=no
 
   # zlib is available in android.

doc/emacs/android.texi

@@ -461,8 +461,15 @@ On Android 2.3 and earlier, the function @code{gui-selection-owner-p}
 always returns @code{nil} for the clipboard selection.
 
 @item
-On Android 3.0 and later, Emacs can only access clipboard data when
-one of its frames has the input focus.
+Between Android 3.0 and Android 9.0, Emacs is able to access the
+clipboard whenever it wants, and @code{gui-selection-owner-p} always
+returns accurate results.
+
+@item
+Under Android 10.0 and later, Emacs can only access clipboard data
+when one of its frames has the input focus, and
+@code{gui-selection-owner-p} always returns @code{nil} for the
+clipboard selection.
 @end itemize
 
   Since the Android system itself has no concept of a primary

java/org/gnu/emacs/EmacsSdk11Clipboard.java

@@ -25,6 +25,8 @@
 
 import android.util.Log;
 
+import android.os.Build;
+
 import java.io.UnsupportedEncodingException;
 
 /* This class implements EmacsClipboard for Android 3.0 and later
@@ -43,7 +45,12 @@ public class EmacsSdk11Clipboard extends EmacsClipboard
   EmacsSdk11Clipboard ()
   {
     manager = EmacsService.SERVICE.getClipboardManager ();
-    manager.addPrimaryClipChangedListener (this);
+
+    /* The system forbids Emacs from reading clipboard data in the
+       background under Android 10 or later.  */
+
+    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.Q)
+      manager.addPrimaryClipChangedListener (this);
   }
 
   @Override
@@ -105,6 +112,9 @@ public class EmacsSdk11Clipboard extends EmacsClipboard
   public synchronized int
   ownsClipboard ()
   {
+    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q)
+      return -1;
+
     return ownsClipboard ? 1 : 0;
   }