Add emacsclient desktop file equivalent on Android

* doc/emacs/android.texi (Android File System):
* java/AndroidManifest.xml.in: Update with new activity.  Remove
Android 10 restrictions through a special flag.

* java/org/gnu/emacs/EmacsNative.java (getProcName): New
function.
* java/org/gnu/emacs/EmacsOpenActivity.java (EmacsOpenActivity):
New file.
* java/org/gnu/emacs/EmacsService.java (getLibraryDirection):
Remove unused annotation.
* lib-src/emacsclient.c (decode_options): Set alt_display on
Android.
* src/android.c (android_proc_name): New function.
(NATIVE_NAME): Export via JNI.

1 files changed, 44 insertions, 0 deletions

diff --git a/src/android.c b/src/android.c
index 57a95bcd4f9..a0e64471a05 100644
--- a/src/android.c
+++ b/src/android.c
@@ -1369,6 +1369,27 @@ android_get_home_directory (void)
   return android_files_dir;
 }
 
+/* Return the name of the file behind a file descriptor FD by reading
+   /proc/self/fd/.  Place the name in BUFFER, which should be able to
+   hold size bytes.  Value is 0 upon success, and 1 upon failure.  */
+
+static int
+android_proc_name (int fd, char *buffer, size_t size)
+{
+  char format[sizeof "/proc/self/fd/"
+              + INT_STRLEN_BOUND (int)];
+  ssize_t read;
+
+  sprintf (format, "/proc/self/fd/%d", fd);
+  read = readlink (format, buffer, size - 1);
+
+  if (read == -1)
+    return 1;
+
+  buffer[read] = '\0';
+  return 0;
+}
+
 
 
 /* JNI functions called by Java.  */
@@ -1598,6 +1619,29 @@ NATIVE_NAME (setEmacsParams) (JNIEnv *env, jobject object,
      now.  */
 }
 
+JNIEXPORT jobject JNICALL
+NATIVE_NAME (getProcName) (JNIEnv *env, jobject object, jint fd)
+{
+  char buffer[PATH_MAX + 1];
+  size_t length;
+  jbyteArray array;
+
+  if (android_proc_name (fd, buffer, PATH_MAX + 1))
+    return NULL;
+
+  /* Return a byte array, as Java strings cannot always encode file
+     names.  */
+  length = strlen (buffer);
+  array = (*env)->NewByteArray (env, length);
+  if (!array)
+    return NULL;
+
+  (*env)->SetByteArrayRegion (env, array, 0, length,
+                              (jbyte *) buffer);
+
+  return array;
+}
+
 /* Initialize service_class, aborting if something goes wrong.  */
 
 static void