ZygoteInit: more dead code cleanup

ZYGOTE_FORK_MODE has been set to false since 2009, and the
code indicates that runForkMode() was "retained for reference only."
Remove this dead code. There will always be a reference to this code
in git.

Change-Id: Iddfdca8379fdc6521febea81e553de763b6f4fd0

core/java/com/android/internal/os/ZygoteInit.java

@@ -19,10 +19,8 @@ package com.android.internal.os;
 import static libcore.io.OsConstants.S_IRWXG;
 import static libcore.io.OsConstants.S_IRWXO;
 
-import android.content.pm.ActivityInfo;
 import android.content.res.Resources;
 import android.content.res.TypedArray;
-import android.graphics.drawable.Drawable;
 import android.net.LocalServerSocket;
 import android.os.Debug;
 import android.os.Process;
@@ -87,12 +85,6 @@ public class ZygoteInit {
      */
     static final int GC_LOOP_COUNT = 10;
 
-    /**
-     * If true, zygote forks for each peer. If false, a select loop is used
-     * inside a single process. The latter is preferred.
-     */
-    private static final boolean ZYGOTE_FORK_MODE = false;
-
     /**
      * The name of a resource file that contains classes to preload.
      */
@@ -549,11 +541,7 @@ public class ZygoteInit {
 
             Log.i(TAG, "Accepting command socket connections");
 
-            if (ZYGOTE_FORK_MODE) {
+            runSelectLoop();
-                runForkMode();
-            } else {
-                runSelectLoopMode();
-            }
 
             closeServerSocket();
         } catch (MethodAndArgsCaller caller) {
@@ -565,44 +553,6 @@ public class ZygoteInit {
         }
     }
 
-    /**
-     * Runs the zygote in accept-and-fork mode. In this mode, each peer
-     * gets its own zygote spawner process. This code is retained for
-     * reference only.
-     *
-     * @throws MethodAndArgsCaller in a child process when a main() should
-     * be executed.
-     */
-    private static void runForkMode() throws MethodAndArgsCaller {
-        while (true) {
-            ZygoteConnection peer = acceptCommandPeer();
-
-            int pid;
-
-            pid = Zygote.fork();
-
-            if (pid == 0) {
-                // The child process should handle the peer requests
-
-                // The child does not accept any more connections
-                try {
-                    sServerSocket.close();
-                } catch (IOException ex) {
-                    Log.e(TAG, "Zygote Child: error closing sockets", ex);
-                } finally {
-                    sServerSocket = null;
-                }
-
-                peer.run();
-                break;
-            } else if (pid > 0) {
-                peer.closeSocket();
-            } else {
-                throw new RuntimeException("Error invoking fork()");
-            }
-        }
-    }
-
     /**
      * Runs the zygote process's select loop. Accepts new connections as
      * they happen, and reads commands from connections one spawn-request's
@@ -611,9 +561,9 @@ public class ZygoteInit {
      * @throws MethodAndArgsCaller in a child process when a main() should
      * be executed.
      */
-    private static void runSelectLoopMode() throws MethodAndArgsCaller {
+    private static void runSelectLoop() throws MethodAndArgsCaller {
-        ArrayList<FileDescriptor> fds = new ArrayList();
+        ArrayList<FileDescriptor> fds = new ArrayList<FileDescriptor>();
-        ArrayList<ZygoteConnection> peers = new ArrayList();
+        ArrayList<ZygoteConnection> peers = new ArrayList<ZygoteConnection>();
         FileDescriptor[] fdArray = new FileDescriptor[4];
 
         fds.add(sServerSocket.getFileDescriptor());