Update Android port

* java/debug.sh (is_root): Go back to using unix sockets; allow
adb to forward them correctly.
* java/org/gnu/emacs/EmacsInputConnection.java
(getExtractedText): Don't print text if NULL.
* java/org/gnu/emacs/EmacsService.java (EmacsService): New field
`imSyncInProgress'.
(updateIC): If an IM sync might be in progress, avoid deadlocks.
* java/org/gnu/emacs/EmacsView.java (onCreateInputConnection):
Set `imSyncInProgress' across synchronization point.
* src/android.c (android_check_query): Use __atomic_store_n.
(android_answer_query): New function.
(android_begin_query): Set `android_servicing_query' to 2.
Check once, and don't spin waiting for query to complete.
(android_end_query): Use __atomic_store_n.
(android_run_in_emacs_thread): Compare-and-exchange flag.  If
originally 1, fail.
* src/textconv.c (really_set_composing_text): Clear conversion
region if text is empty.

3 files changed, 43 insertions, 1 deletions

diff --git a/java/org/gnu/emacs/EmacsInputConnection.java b/java/org/gnu/emacs/EmacsInputConnection.java
index 21bbaca5d07..420da58c0f8 100644
--- a/java/org/gnu/emacs/EmacsInputConnection.java
+++ b/java/org/gnu/emacs/EmacsInputConnection.java
@@ -286,6 +286,14 @@ public final class EmacsInputConnection extends BaseInputConnection
       text = EmacsNative.getExtractedText (windowHandle, request,
                                            flags);
 
+    if (text == null)
+      {
+        if (EmacsService.DEBUG_IC)
+          Log.d (TAG, "getExtractedText: text is NULL");
+
+        return null;
+      }
+
     if (EmacsService.DEBUG_IC)
       Log.d (TAG, "getExtractedText: " + text.text + " @"
              + text.startOffset + ":" + text.selectionStart
diff --git a/java/org/gnu/emacs/EmacsService.java b/java/org/gnu/emacs/EmacsService.java
index 546d22627c5..2f35933a7d1 100644
--- a/java/org/gnu/emacs/EmacsService.java
+++ b/java/org/gnu/emacs/EmacsService.java
@@ -104,6 +104,9 @@ public final class EmacsService extends Service
      performing drawing calls.  */
   private static final boolean DEBUG_THREADS = false;
 
+  /* Whether or not onCreateInputMethod is calling getSelection.  */
+  public static volatile boolean imSyncInProgress;
+
   /* Return the directory leading to the directory in which native
      library files are stored on behalf of CONTEXT.  */
 
@@ -636,16 +639,41 @@ public final class EmacsService extends Service
             int newSelectionEnd, int composingRegionStart,
             int composingRegionEnd)
   {
+    boolean wasSynchronous;
+
     if (DEBUG_IC)
       Log.d (TAG, ("updateIC: " + window + " " + newSelectionStart
                    + " " + newSelectionEnd + " "
                    + composingRegionStart + " "
                    + composingRegionEnd));
+
+    /* `updateSelection' holds an internal lock that is also taken
+       before `onCreateInputConnection' (in EmacsView.java) is called;
+       when that then asks the UI thread for the current selection, a
+       dead lock results.  To remedy this, reply to any synchronous
+       queries now -- and prohibit more queries for the duration of
+       `updateSelection' -- if EmacsView may have been asking for the
+       value of the region.  */
+
+    wasSynchronous = false;
+    if (EmacsService.imSyncInProgress)
+      {
+        /* `beginSynchronous' will answer any outstanding queries and
+           signal that one is now in progress, thereby preventing
+           `getSelection' from blocking.  */
+
+        EmacsNative.beginSynchronous ();
+        wasSynchronous = true;
+      }
+
     window.view.imManager.updateSelection (window.view,
                                            newSelectionStart,
                                            newSelectionEnd,
                                            composingRegionStart,
                                            composingRegionEnd);
+
+    if (wasSynchronous)
+      EmacsNative.endSynchronous ();
   }
 
   public void
diff --git a/java/org/gnu/emacs/EmacsView.java b/java/org/gnu/emacs/EmacsView.java
index 09bc9d719d3..bb450bb8e6b 100644
--- a/java/org/gnu/emacs/EmacsView.java
+++ b/java/org/gnu/emacs/EmacsView.java
@@ -628,8 +628,14 @@ public final class EmacsView extends ViewGroup
       }
 
     /* Obtain the current position of point and set it as the
-       selection.  */
+       selection.  Don't do this under one specific situation: if
+       `android_update_ic' is being called in the main thread, trying
+       to synchronize with it can cause a dead lock in the IM
+       manager.  */
+
+    EmacsService.imSyncInProgress = true;
     selection = EmacsNative.getSelection (window.handle);
+    EmacsService.imSyncInProgress = false;
 
     if (selection != null)
       Log.d (TAG, "onCreateInputConnection: current selection is: "