Renamed Sandboxed process to Child process

content/public/android/java/src/org/chromium/content/browser/SandboxedProcessLauncher.java

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-package org.chromium.content.browser;
-
-import android.content.Context;
-import android.os.RemoteException;
-import android.util.Log;
-import android.view.Surface;
-
-import java.util.ArrayList;
-import java.util.Map;
-import java.util.concurrent.ConcurrentHashMap;
-
-import org.chromium.base.CalledByNative;
-import org.chromium.base.JNINamespace;
-import org.chromium.base.ThreadUtils;
-import org.chromium.content.app.LibraryLoader;
-import org.chromium.content.common.CommandLine;
-import org.chromium.content.common.ISandboxedProcessCallback;
-import org.chromium.content.common.ISandboxedProcessService;
-
-/**
- * This class provides the method to start/stop SandboxedProcess called by
- * native.
- */
-@JNINamespace("content")
-public class SandboxedProcessLauncher {
-    private static String TAG = "SandboxedProcessLauncher";
-
-    // The upper limit on the number of simultaneous service process instances supported.
-    // This must not exceed total number of SandboxedProcessServiceX classes declared in
-    // this package, and defined as services in the embedding application's manifest file.
-    // (See {@link SandboxedProcessService} for more details on defining the services.)
-    /* package */ static final int MAX_REGISTERED_SERVICES = 6;
-    private static final SandboxedProcessConnection[] mConnections =
-        new SandboxedProcessConnection[MAX_REGISTERED_SERVICES];
-    // The list of free slots in mConnections.  When looking for a free connection,
-    // the first index in that list should be used. When a connection is freed, its index
-    // is added to the end of the list. This is so that we avoid immediately reusing a freed
-    // connection (see bug crbug.com/164069): the framework might keep a service process alive
-    // when it's been unbound for a short time.  If a connection to that same service is bound
-    // at that point, the process is reused and bad things happen (mostly static variables are
-    // set when we don't expect them to).
-    // SHOULD BE ACCESSED WITH THE mConnections LOCK.
-    private static final ArrayList<Integer> mFreeConnectionIndices =
-        new ArrayList<Integer>(MAX_REGISTERED_SERVICES);
-    static {
-        for (int i = 0; i < MAX_REGISTERED_SERVICES; i++) {
-            mFreeConnectionIndices.add(i);
-        }
-    }
-
-    private static SandboxedProcessConnection allocateConnection(Context context) {
-        SandboxedProcessConnection.DeathCallback deathCallback =
-            new SandboxedProcessConnection.DeathCallback() {
-                @Override
-                public void onSandboxedProcessDied(int pid) {
-                    stop(pid);
-                }
-            };
-        synchronized (mConnections) {
-            if (mFreeConnectionIndices.isEmpty()) {
-                Log.w(TAG, "Ran out of sandboxed services.");
-                return null;
-            }
-            int slot = mFreeConnectionIndices.remove(0);
-            assert mConnections[slot] == null;
-            mConnections[slot] = new SandboxedProcessConnection(context, slot, deathCallback);
-            return mConnections[slot];
-        }
-    }
-
-    private static SandboxedProcessConnection allocateBoundConnection(Context context,
-            String[] commandLine) {
-        SandboxedProcessConnection connection = allocateConnection(context);
-        if (connection != null) {
-            String libraryName = LibraryLoader.getLibraryToLoad();
-            assert libraryName != null : "Attempting to launch a sandbox process without first "
-                    + "calling LibraryLoader.setLibraryToLoad";
-            connection.bind(libraryName, commandLine);
-        }
-        return connection;
-    }
-
-    private static void freeConnection(SandboxedProcessConnection connection) {
-        if (connection == null) {
-            return;
-        }
-        int slot = connection.getServiceNumber();
-        synchronized (mConnections) {
-            if (mConnections[slot] != connection) {
-                int occupier = mConnections[slot] == null ?
-                        -1 : mConnections[slot].getServiceNumber();
-                Log.e(TAG, "Unable to find connection to free in slot: " + slot +
-                        " already occupied by service: " + occupier);
-                assert false;
-            } else {
-                mConnections[slot] = null;
-                assert !mFreeConnectionIndices.contains(slot);
-                mFreeConnectionIndices.add(slot);
-            }
-        }
-    }
-
-    public static int getNumberOfConnections() {
-        synchronized (mConnections) {
-            return mFreeConnectionIndices.size();
-        }
-    }
-
-    // Represents an invalid process handle; same as base/process.h kNullProcessHandle.
-    private static final int NULL_PROCESS_HANDLE = 0;
-
-    // Map from pid to SandboxedService connection.
-    private static Map<Integer, SandboxedProcessConnection> mServiceMap =
-            new ConcurrentHashMap<Integer, SandboxedProcessConnection>();
-
-    // A pre-allocated and pre-bound connection ready for connection setup, or null.
-    static SandboxedProcessConnection mSpareConnection = null;
-
-    /**
-     * Returns the sandboxed process service interface for the given pid. This may be called on
-     * any thread, but the caller must assume that the service can disconnect at any time. All
-     * service calls should catch and handle android.os.RemoteException.
-     *
-     * @param pid The pid (process handle) of the service obtained from {@link #start}.
-     * @return The ISandboxedProcessService or null if the service no longer exists.
-     */
-    public static ISandboxedProcessService getSandboxedService(int pid) {
-        SandboxedProcessConnection connection = mServiceMap.get(pid);
-        if (connection != null) {
-            return connection.getService();
-        }
-        return null;
-    }
-
-    /**
-     * Should be called early in startup so the work needed to spawn the sandboxed process can
-     * be done in parallel to other startup work. Must not be called on the UI thread.
-     * @param context the application context used for the connection.
-     */
-    public static synchronized void warmUp(Context context) {
-        assert !ThreadUtils.runningOnUiThread();
-        if (mSpareConnection == null) {
-            mSpareConnection = allocateBoundConnection(context, null);
-        }
-    }
-
-    /**
-     * Spawns and connects to a sandboxed process. May be called on any thread. It will not
-     * block, but will instead callback to {@link #nativeOnSandboxedProcessStarted} when the
-     * connection is established. Note this callback will not necessarily be from the same thread
-     * (currently it always comes from the main thread).
-     *
-     * @param context Context used to obtain the application context.
-     * @param commandLine The sandboxed process command line argv.
-     * @param file_ids The ID that should be used when mapping files in the created process.
-     * @param file_fds The file descriptors that should be mapped in the created process.
-     * @param file_auto_close Whether the file descriptors should be closed once they were passed to
-     * the created process.
-     * @param clientContext Arbitrary parameter used by the client to distinguish this connection.
-     */
-    @CalledByNative
-    static void start(
-            Context context,
-            final String[] commandLine,
-            int[] fileIds,
-            int[] fileFds,
-            boolean[] fileAutoClose,
-            final int clientContext) {
-        assert fileIds.length == fileFds.length && fileFds.length == fileAutoClose.length;
-        FileDescriptorInfo[] filesToBeMapped = new FileDescriptorInfo[fileFds.length];
-        for (int i = 0; i < fileFds.length; i++) {
-            filesToBeMapped[i] =
-                    new FileDescriptorInfo(fileIds[i], fileFds[i], fileAutoClose[i]);
-        }
-        assert clientContext != 0;
-        SandboxedProcessConnection allocatedConnection;
-        synchronized (SandboxedProcessLauncher.class) {
-            allocatedConnection = mSpareConnection;
-            mSpareConnection = null;
-        }
-        if (allocatedConnection == null) {
-            allocatedConnection = allocateBoundConnection(context, commandLine);
-            if (allocatedConnection == null) {
-                // Notify the native code so it can free the heap allocated callback.
-                nativeOnSandboxedProcessStarted(clientContext, 0);
-                return;
-            }
-        }
-        final SandboxedProcessConnection connection = allocatedConnection;
-        Log.d(TAG, "Setting up connection to process: slot=" + connection.getServiceNumber());
-        // Note: This runnable will be executed when the sandboxed connection is setup.
-        final Runnable onConnect = new Runnable() {
-            @Override
-            public void run() {
-                final int pid = connection.getPid();
-                Log.d(TAG, "on connect callback, pid=" + pid + " context=" + clientContext);
-                if (pid != NULL_PROCESS_HANDLE) {
-                    mServiceMap.put(pid, connection);
-                } else {
-                    freeConnection(connection);
-                }
-                nativeOnSandboxedProcessStarted(clientContext, pid);
-            }
-        };
-        connection.setupConnection(commandLine, filesToBeMapped, createCallback(), onConnect);
-    }
-
-    /**
-     * Terminates a sandboxed process. This may be called from any thread.
-     *
-     * @param pid The pid (process handle) of the service connection obtained from {@link #start}.
-     */
-    @CalledByNative
-    static void stop(int pid) {
-        Log.d(TAG, "stopping sandboxed connection: pid=" + pid);
-
-        SandboxedProcessConnection connection = mServiceMap.remove(pid);
-        if (connection == null) {
-            Log.w(TAG, "Tried to stop non-existent connection to pid: " + pid);
-            return;
-        }
-        connection.unbind();
-        freeConnection(connection);
-    }
-
-    /**
-     * Bind a sandboxed process as a high priority process so that it has the same
-     * priority as the main process. This can be used for the foreground renderer
-     * process to distinguish it from the the background renderer process.
-     *
-     * @param pid The process handle of the service connection obtained from {@link #start}.
-     */
-    static void bindAsHighPriority(int pid) {
-        SandboxedProcessConnection connection = mServiceMap.get(pid);
-        if (connection == null) {
-            Log.w(TAG, "Tried to bind a non-existent connection to pid: " + pid);
-            return;
-        }
-        connection.bindHighPriority();
-    }
-
-    /**
-     * Unbind a high priority process which is bound by {@link #bindAsHighPriority}.
-     *
-     * @param pid The process handle of the service obtained from {@link #start}.
-     */
-    static void unbindAsHighPriority(int pid) {
-        SandboxedProcessConnection connection = mServiceMap.get(pid);
-        if (connection == null) {
-            Log.w(TAG, "Tried to unbind non-existent connection to pid: " + pid);
-            return;
-        }
-        connection.unbindHighPriority(false);
-    }
-
-    /**
-     * This implementation is used to receive callbacks from the remote service.
-     */
-    private static ISandboxedProcessCallback createCallback() {
-        return new ISandboxedProcessCallback.Stub() {
-            /**
-             * This is called by the remote service regularly to tell us about
-             * new values.  Note that IPC calls are dispatched through a thread
-             * pool running in each process, so the code executing here will
-             * NOT be running in our main thread -- so, to update the UI, we need
-             * to use a Handler.
-             */
-            public void establishSurfacePeer(
-                    int pid, Surface surface, int primaryID, int secondaryID) {
-                // TODO(sievers): This should call into native and pass the Surface to the
-                // right media player instance.
-            }
-        };
-    };
-
-    private static native void nativeOnSandboxedProcessStarted(int clientContext, int pid);
-}