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.

4 files changed, 54 insertions, 7 deletions

diff --git a/java/debug.sh b/java/debug.sh
index 339b3604810..0458003fe72 100755
--- a/java/debug.sh
+++ b/java/debug.sh
@@ -19,6 +19,7 @@
 ## along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
 
 set -m
+set -x
 oldpwd=`pwd`
 cd `dirname $0`
 
@@ -310,22 +311,26 @@ rm -f /tmp/file-descriptor-stamp
 
 if [ -z "$gdbserver" ]; then
     if [ "$is_root" = "yes" ]; then
-        adb -s $device shell $gdbserver_bin --once \
+        adb -s $device shell $gdbserver_bin --multi \
             "+/data/local/tmp/debug.$package.socket" --attach $pid >&5 &
         gdb_socket="localfilesystem:/data/local/tmp/debug.$package.socket"
-    else        
-        adb -s $device shell run-as $package $gdbserver_bin --once \
+    else
+        adb -s $device shell run-as $package $gdbserver_bin --multi \
             "+debug.$package.socket" --attach $pid >&5 &
         gdb_socket="localfilesystem:$app_data_dir/debug.$package.socket"
     fi
 else
     # Normally the program cannot access $gdbserver_bin when it is
     # placed in /data/local/tmp.
-    adb -s $device shell run-as $package $gdbserver_cmd --once \
-        "0.0.0.0:7654" --attach $pid >&5 &
-    gdb_socket="tcp:7654"
+    adb -s $device shell run-as $package $gdbserver_cmd --multi \
+        "+debug.$package.socket" --attach $pid >&5 &
+    gdb_socket="localfilesystem:$app_data_dir/debug.$package.socket"
 fi
 
+# In order to allow adb to forward to the gdbserver socket, make the
+# app data directory a+x.
+adb -s $device shell run-as $package chmod a+x $app_data_dir
+
 # Wait until gdbserver successfully runs.
 line=
 while read -u 5 line; do
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: "