Use the new forwarder2's Daemon implementation in device_forwarder.

tools/android/forwarder2/device_forwarder_main.cc

Index: tools/android/forwarder2/device_forwarder_main.cc
diff --git a/tools/android/forwarder2/device_forwarder_main.cc b/tools/android/forwarder2/device_forwarder_main.cc
index 4a731b20a796e754da7333ecc9fe5ff6601cded5..c6f044291a893936b69f015f3dcaa5959ff011e2 100644
--- a/tools/android/forwarder2/device_forwarder_main.cc
+++ b/tools/android/forwarder2/device_forwarder_main.cc
@@ -8,20 +8,32 @@
 
 #include <string>
 
+#include "base/at_exit.h"
+#include "base/bind.h"
 #include "base/command_line.h"
+#include "base/compiler_specific.h"
 #include "base/logging.h"
+#include "base/string_piece.h"
 #include "base/stringprintf.h"
-#include "tools/android/common/daemon.h"
+#include "base/threading/thread.h"
+#include "tools/android/forwarder2/common.h"
+#include "tools/android/forwarder2/daemon.h"
 #include "tools/android/forwarder2/device_controller.h"
 #include "tools/android/forwarder2/pipe_notifier.h"
 
+namespace forwarder2 {
 namespace {
 
 // Leaky global instance, accessed from the signal handler.
 forwarder2::PipeNotifier* g_notifier = NULL;
 
-// Unix domain socket name for Device Controller.
-const char kDefaultAdbSocket[] = "chrome_device_forwarder";
+const int kBufSize = 256;
+
+const char kPIDFilePath[] = "/data/local/tmp/chrome_device_forwarder_pid";
+const char kDaemonIdentifier[] = "chrome_device_forwarder_daemon";
+
+const char kKillServerCommand[] = "kill-server";
+const char kStartCommand[] = "start";
 
 void KillHandler(int /* unused */) {
   CHECK(g_notifier);
@@ -29,38 +41,141 @@ void KillHandler(int /* unused */) {
     exit(1);
 }
 
-}  // namespace
+// Lets the daemon fetch the exit notifier file descriptor.
+int GetExitNotifierFD() {
+  DCHECK(g_notifier);
+  return g_notifier->receiver_fd();
+}
 
-int main(int argc, char** argv) {
-  printf("Device forwarder to forward connections to the Host machine.\n");
-  printf("Like 'adb forward' but in the reverse direction\n");
-
-  CommandLine command_line(argc, argv);
-  std::string adb_socket_path = command_line.GetSwitchValueASCII("adb_sock");
-  if (adb_socket_path.empty())
-    adb_socket_path = kDefaultAdbSocket;
-  if (tools::HasHelpSwitch(command_line)) {
-    tools::ShowHelp(
-        argv[0],
-        "[--adb_sock=<adb sock>]",
-        base::StringPrintf(
-            "  <adb sock> is the Abstract Unix Domain Socket path "
-            " where Adb is configured to forward from."
-            " Default is %s\n", kDefaultAdbSocket).c_str());
-    return 0;
+class ServerDelegate : public Daemon::ServerDelegate {
+ public:
+  // Daemon::ServerDelegate:
+  virtual void Init() OVERRIDE {
+    DCHECK(!g_notifier);
+    g_notifier = new forwarder2::PipeNotifier();
+    signal(SIGTERM, KillHandler);
+    signal(SIGINT, KillHandler);
+    controller_thread_.reset(new base::Thread("controller_thread"));
+    controller_thread_->Start();
   }
-  if (!tools::HasNoSpawnDaemonSwitch(command_line))
-    tools::SpawnDaemon(0);
 
-  g_notifier = new forwarder2::PipeNotifier();
+  virtual void OnClientConnected(scoped_ptr<Socket> client_socket) OVERRIDE {
+    char buf[kBufSize];
+    const int bytes_read = client_socket->Read(buf, sizeof(buf));
+    if (bytes_read <= 0) {
+      if (client_socket->exited())
+        return;
+      PError("Read()");
+      return;
+    }
+    const std::string adb_socket_path(buf, bytes_read);
+    if (adb_socket_path == adb_socket_path_) {
+      client_socket->WriteString("OK");
+      return;
+    }
+    if (!adb_socket_path_.empty()) {
+      client_socket->WriteString(
+          base::StringPrintf(
+              "ERROR: Device controller already running (adb_socket_path=%s)",
+              adb_socket_path_.c_str()));
+      return;
+    }
+    adb_socket_path_ = adb_socket_path;
+    controller_thread_->message_loop()->PostTask(
+        FROM_HERE,
+        base::Bind(&ServerDelegate::StartController, adb_socket_path,
+                   GetExitNotifierFD(), base::Passed(&client_socket)));
+  }
 
-  signal(SIGTERM, KillHandler);
-  signal(SIGINT, KillHandler);
-  CHECK(g_notifier);
-  forwarder2::DeviceController controller(g_notifier->receiver_fd());
-  if (!controller.Init(adb_socket_path))
+  virtual void OnServerExited() OVERRIDE {}
+
+ private:
+  static void StartController(const std::string& adb_socket_path,
+                              int exit_notifier_fd,
+                              scoped_ptr<Socket> client_socket) {
+    forwarder2::DeviceController controller(exit_notifier_fd);
+    if (!controller.Init(adb_socket_path)) {
+      client_socket->WriteString(
+          base::StringPrintf("ERROR: Could not initialize device controller "
+                             "with ADB socket path: %s",
+                             adb_socket_path.c_str()));
+      return;
+    }
+    client_socket->WriteString("OK");
+    client_socket->Close();
+    // Note that the following call is blocking which explains why the device
+    // controller has to live on a separate thread (so that the daemon command
+    // server is not blocked).
+    controller.Start();
+  }
+
+  base::AtExitManager at_exit_manager_;  // Used by base::Thread.
+  scoped_ptr<base::Thread> controller_thread_;
+  std::string adb_socket_path_;
+};
+
+class ClientDelegate : public Daemon::ClientDelegate {
+ public:
+  ClientDelegate(const std::string& adb_socket)
+      : adb_socket_(adb_socket),
+        has_failed_(false) {
+  }
+
+  bool has_failed() const { return has_failed_; }
+
+  // Daemon::ClientDelegate:
+  virtual void OnDaemonReady(Socket* daemon_socket) OVERRIDE {
+    // Send the adb socket path to the daemon.
+    CHECK(daemon_socket->Write(adb_socket_.c_str(),
+                               adb_socket_.length()));
+    char buf[kBufSize];
+    const int bytes_read = daemon_socket->Read(
+        buf, sizeof(buf) - 1 /* leave space for null terminator */);
+    CHECK_GT(bytes_read, 0);
+    DCHECK(bytes_read < sizeof(buf));
+    buf[bytes_read] = 0;
+    base::StringPiece msg(buf, bytes_read);
+    if (msg.starts_with("ERROR")) {
+      LOG(ERROR) << msg;
+      has_failed_ = true;
+      return;
+    }
+  }
+
+ private:
+  const std::string adb_socket_;
+  bool has_failed_;
+};
+
+int RunDeviceForwarder(int argc, char** argv) {
+  if (argc != 2) {
+    fprintf(stderr,
+            "Usage: %s kill-server|<adb_socket>\n"
+            "  <adb_socket> is the abstract Unix Domain Socket path "
+            "where Adb is configured to forward from.\n", argv[0]);
     return 1;
-  printf("Starting Device Forwarder.\n");
-  controller.Start();
-  return 0;
+  }
+  CommandLine::Init(argc, argv);  // Needed by logging.
+  const char* const command =
+      !strcmp(argv[1], kKillServerCommand) ? kKillServerCommand : kStartCommand;
+  ClientDelegate client_delegate(argv[1]);
+  ServerDelegate daemon_delegate;
+  const char kLogFilePath[] = "";  // Log to logcat.
+  Daemon daemon(kLogFilePath, kPIDFilePath, kDaemonIdentifier, &client_delegate,
+                &daemon_delegate, &GetExitNotifierFD);
+
+  if (command == kKillServerCommand)
+    return !daemon.Kill();
+
+  DCHECK(command == kStartCommand);
+  if (!daemon.SpawnIfNeeded())
+    return 1;
+  return client_delegate.has_failed();
+}
+
+}  // namespace
+}  // namespace forwarder2
+
+int main(int argc, char** argv) {
+  return forwarder2::RunDeviceForwarder(argc, argv);
 }