toolkit/xre/nsNativeAppSupportUnix.cpp
author Kris Maglione <maglione.k@gmail.com>
Tue, 02 May 2017 17:54:18 -0700
changeset 407402 b49bd726c8a6e955c672df17b2b9134ab3ad34d5
parent 357413 a42e8a53dc39eee4d27c33b184f8f6d5dff367cb
child 415974 9846de3bd9545fb2c2b803a36af85568ccf2473b
permissions -rw-r--r--
Bug 1359653: Part 3 - Add a clear() method and move asssignment operator to AutoCleanLinkedList. r=waldo MozReview-Commit-ID: 2bUTMPviJzg

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsNativeAppSupportBase.h"
#include "nsCOMPtr.h"
#include "nsXPCOM.h"
#include "nsISupportsPrimitives.h"
#include "nsIObserverService.h"
#include "nsIAppStartup.h"
#include "nsServiceManagerUtils.h"
#include "prlink.h"
#include "nsXREDirProvider.h"
#include "nsReadableUtils.h"

#include "nsIFile.h"
#include "nsDirectoryServiceDefs.h"
#include "nsICommandLineRunner.h"
#include "nsIWindowMediator.h"
#include "nsPIDOMWindow.h"
#include "nsIDocShell.h"
#include "nsIBaseWindow.h"
#include "nsIWidget.h"
#include "nsIWritablePropertyBag2.h"
#include "nsIPrefService.h"
#include "mozilla/Services.h"

#include <stdlib.h>
#include <glib.h>
#include <glib-object.h>
#include <gtk/gtk.h>

#ifdef MOZ_X11
#include <gdk/gdkx.h>
#include <X11/ICE/ICElib.h>
#include <X11/SM/SMlib.h>
#include <fcntl.h>
#include "nsThreadUtils.h"

#include <pwd.h>
#endif

#ifdef MOZ_ENABLE_DBUS
#include <dbus/dbus.h>
#endif

#define MIN_GTK_MAJOR_VERSION 2
#define MIN_GTK_MINOR_VERSION 10
#define UNSUPPORTED_GTK_MSG "We're sorry, this application requires a version of the GTK+ library that is not installed on your computer.\n\n\
You have GTK+ %d.%d.\nThis application requires GTK+ %d.%d or newer.\n\n\
Please upgrade your GTK+ library if you wish to use this application."

#if MOZ_X11
#undef IceSetIOErrorHandler
#undef IceAddConnectionWatch
#undef IceConnectionNumber
#undef IceProcessMessages
#undef IceGetConnectionContext
#undef SmcInteractDone
#undef SmcSaveYourselfDone
#undef SmcInteractRequest
#undef SmcCloseConnection
#undef SmcOpenConnection
#undef SmcSetProperties

typedef IceIOErrorHandler (*IceSetIOErrorHandlerFn) (IceIOErrorHandler);
typedef int (*IceAddConnectionWatchFn) (IceWatchProc, IcePointer);
typedef int (*IceConnectionNumberFn) (IceConn);
typedef IceProcessMessagesStatus (*IceProcessMessagesFn) (IceConn, IceReplyWaitInfo*, Bool*);
typedef IcePointer (*IceGetConnectionContextFn) (IceConn);

typedef void (*SmcInteractDoneFn) (SmcConn, Bool);
typedef void (*SmcSaveYourselfDoneFn) (SmcConn, Bool);
typedef int (*SmcInteractRequestFn) (SmcConn, int, SmcInteractProc, SmPointer);
typedef SmcCloseStatus (*SmcCloseConnectionFn) (SmcConn, int, char**);
typedef SmcConn (*SmcOpenConnectionFn) (char*, SmPointer, int, int,
                                        unsigned long, SmcCallbacks*,
                                        const char*, char**, int, char*);
typedef void (*SmcSetPropertiesFn) (SmcConn, int, SmProp**);

static IceSetIOErrorHandlerFn IceSetIOErrorHandlerPtr;
static IceAddConnectionWatchFn IceAddConnectionWatchPtr;
static IceConnectionNumberFn IceConnectionNumberPtr;
static IceProcessMessagesFn IceProcessMessagesPtr;
static IceGetConnectionContextFn IceGetConnectionContextPtr;
static SmcInteractDoneFn SmcInteractDonePtr;
static SmcSaveYourselfDoneFn SmcSaveYourselfDonePtr;
static SmcInteractRequestFn SmcInteractRequestPtr;
static SmcCloseConnectionFn SmcCloseConnectionPtr;
static SmcOpenConnectionFn SmcOpenConnectionPtr;
static SmcSetPropertiesFn SmcSetPropertiesPtr;

#define IceSetIOErrorHandler IceSetIOErrorHandlerPtr
#define IceAddConnectionWatch IceAddConnectionWatchPtr
#define IceConnectionNumber IceConnectionNumberPtr
#define IceProcessMessages IceProcessMessagesPtr
#define IceGetConnectionContext IceGetConnectionContextPtr
#define SmcInteractDone SmcInteractDonePtr
#define SmcSaveYourselfDone SmcSaveYourselfDonePtr
#define SmcInteractRequest SmcInteractRequestPtr
#define SmcCloseConnection SmcCloseConnectionPtr
#define SmcOpenConnection SmcOpenConnectionPtr
#define SmcSetProperties SmcSetPropertiesPtr

enum ClientState {
  STATE_DISCONNECTED,
  STATE_REGISTERING,
  STATE_IDLE,
  STATE_INTERACTING,
  STATE_SHUTDOWN_CANCELLED
};

static const char *gClientStateTable[] = {
  "DISCONNECTED",
  "REGISTERING",
  "IDLE",
  "INTERACTING",
  "SHUTDOWN_CANCELLED"
};

static LazyLogModule sMozSMLog("MozSM");
#endif /* MOZ_X11 */

class nsNativeAppSupportUnix : public nsNativeAppSupportBase
{
public:
#if MOZ_X11
  nsNativeAppSupportUnix(): mSessionConnection(nullptr),
                            mClientState(STATE_DISCONNECTED) {};
  ~nsNativeAppSupportUnix()
  {
    // this goes out of scope after "web-workers-shutdown" async shutdown phase
    // so it's safe to disconnect here (i.e. the application won't lose data)
    DisconnectFromSM();
  };

  void DisconnectFromSM();
#endif
  NS_IMETHOD Start(bool* aRetVal);
  NS_IMETHOD Stop(bool *aResult);
  NS_IMETHOD Enable();

private:
#if MOZ_X11
  static void SaveYourselfCB(SmcConn smc_conn, SmPointer client_data,
                             int save_style, Bool shutdown, int interact_style,
                             Bool fast);
  static void DieCB(SmcConn smc_conn, SmPointer client_data);
  static void InteractCB(SmcConn smc_conn, SmPointer client_data);
  static void SaveCompleteCB(SmcConn smc_conn, SmPointer client_data) {};
  static void ShutdownCancelledCB(SmcConn smc_conn, SmPointer client_data);
  void DoInteract();
  void SetClientState(ClientState aState)
  {
    mClientState = aState;
    MOZ_LOG(sMozSMLog, LogLevel::Debug, ("New state = %s\n", gClientStateTable[aState]));
  }

  SmcConn mSessionConnection;
  ClientState mClientState;
#endif
};

#if MOZ_X11
static gboolean
process_ice_messages(IceConn connection)
{
  IceProcessMessagesStatus status;

  status = IceProcessMessages(connection, nullptr, nullptr);

  switch (status) {
  case IceProcessMessagesSuccess:
    return TRUE;

  case IceProcessMessagesIOError: {
      nsNativeAppSupportUnix *native =
        static_cast<nsNativeAppSupportUnix *>(IceGetConnectionContext(connection));
      native->DisconnectFromSM();
    }
    return FALSE;

  case IceProcessMessagesConnectionClosed:
    return FALSE;

  default:
    g_assert_not_reached ();
  }
}

static gboolean
ice_iochannel_watch(GIOChannel *channel, GIOCondition condition,
                    gpointer client_data)
{
  return process_ice_messages(static_cast<IceConn>(client_data));
}

static void
ice_connection_watch(IceConn connection, IcePointer  client_data,
                     Bool opening, IcePointer *watch_data)
{
  guint watch_id;

  if (opening) {
    GIOChannel *channel;
    int fd = IceConnectionNumber(connection);

    fcntl(fd, F_SETFD, fcntl(fd, F_GETFD, 0) | FD_CLOEXEC);
    channel = g_io_channel_unix_new(fd);
    watch_id = g_io_add_watch(channel,
                              static_cast<GIOCondition>(G_IO_IN | G_IO_ERR),
                              ice_iochannel_watch, connection);
    g_io_channel_unref(channel);

    *watch_data = GUINT_TO_POINTER(watch_id);
  } else {
    watch_id = GPOINTER_TO_UINT(*watch_data);
    g_source_remove(watch_id);
  }
}

static void
ice_io_error_handler(IceConn connection)
{
  // override the default handler which would exit the application;
  // do nothing and let ICELib handle the failure of the connection gracefully.
}

static void
ice_init(void)
{
  static bool initted = false;

  if (!initted) {
    IceSetIOErrorHandler(ice_io_error_handler);
    IceAddConnectionWatch(ice_connection_watch, nullptr);
    initted = true;
  }
}

void
nsNativeAppSupportUnix::InteractCB(SmcConn smc_conn, SmPointer client_data)
{
  nsNativeAppSupportUnix *self =
    static_cast<nsNativeAppSupportUnix *>(client_data);

  self->SetClientState(STATE_INTERACTING);

  // We do this asynchronously, as we spin the event loop recursively if
  // a dialog is displayed. If we do this synchronously, we don't finish
  // processing the current ICE event whilst the dialog is displayed, which
  // means we won't process any more. libsm hates us if we do the InteractDone
  // with a pending ShutdownCancelled, and we would certainly like to handle Die
  // whilst a dialog is displayed
  NS_DispatchToCurrentThread(NewRunnableMethod(self, &nsNativeAppSupportUnix::DoInteract));
}

void
nsNativeAppSupportUnix::DoInteract()
{
  nsCOMPtr<nsIObserverService> obsServ =
    mozilla::services::GetObserverService();
  if (!obsServ) {
    SmcInteractDone(mSessionConnection, False);
    SmcSaveYourselfDone(mSessionConnection, True);
    SetClientState(STATE_IDLE);
    return;
  }

  nsCOMPtr<nsISupportsPRBool> cancelQuit =
    do_CreateInstance(NS_SUPPORTS_PRBOOL_CONTRACTID);

  bool abortQuit = false;
  if (cancelQuit) {
    cancelQuit->SetData(false);
    obsServ->NotifyObservers(cancelQuit, "quit-application-requested", nullptr);

    cancelQuit->GetData(&abortQuit);
  }

  if (!abortQuit && mClientState == STATE_DISCONNECTED) {
    // The session manager disappeared, whilst we were interacting, so
    // quit now
    nsCOMPtr<nsIAppStartup> appService =
      do_GetService("@mozilla.org/toolkit/app-startup;1");

    if (appService) {
      appService->Quit(nsIAppStartup::eForceQuit);
    }
  } else {
    if (mClientState != STATE_SHUTDOWN_CANCELLED) {
      // Only do this if the shutdown wasn't cancelled
      SmcInteractDone(mSessionConnection, !!abortQuit);
      SmcSaveYourselfDone(mSessionConnection, !abortQuit);
    }

    SetClientState(STATE_IDLE);
  }
}

void
nsNativeAppSupportUnix::SaveYourselfCB(SmcConn smc_conn, SmPointer client_data,
                                       int save_style, Bool shutdown,
                                       int interact_style, Bool fast)
{
  nsNativeAppSupportUnix *self =
    static_cast<nsNativeAppSupportUnix *>(client_data);

  // Expect a SaveYourselfCB if we're registering a new client.
  // All properties are already set in Start() so just reply with
  // SmcSaveYourselfDone if the callback matches the expected signature.
  //
  // Ancient versions (?) of xsm do not follow such an early SaveYourself with
  // SaveComplete. This is a problem if the application freezes interaction
  // while waiting for a response to SmcSaveYourselfDone. So never freeze
  // interaction when in STATE_REGISTERING.
  //
  // That aside, we could treat each combination of flags appropriately and not
  // special-case this.
  if (self->mClientState == STATE_REGISTERING) {
    self->SetClientState(STATE_IDLE);

    if (save_style == SmSaveLocal && interact_style == SmInteractStyleNone &&
        !shutdown && !fast) {
      SmcSaveYourselfDone(self->mSessionConnection, True);
      return;
    }
  }

  if (self->mClientState == STATE_SHUTDOWN_CANCELLED) {
    // The last shutdown request was cancelled whilst we were interacting,
    // and we haven't finished interacting yet. Switch the state back again
    self->SetClientState(STATE_INTERACTING);
  }

  nsCOMPtr<nsIObserverService> obsServ =
    mozilla::services::GetObserverService();
  if (!obsServ) {
    SmcSaveYourselfDone(smc_conn, True);
    return;
  }

  bool status = false;
  if (save_style != SmSaveGlobal) {
    nsCOMPtr<nsISupportsPRBool> didSaveSession =
      do_CreateInstance(NS_SUPPORTS_PRBOOL_CONTRACTID);

    if (!didSaveSession) {
      SmcSaveYourselfDone(smc_conn, True);
      return;
    }

    // Notify observers to save the session state
    didSaveSession->SetData(false);
    obsServ->NotifyObservers(didSaveSession, "session-save", nullptr);

    didSaveSession->GetData(&status);
  }

  // If the interact style permits us to, we are shutting down and we didn't
  // manage to (or weren't asked to) save the local state, then notify the user
  // in advance that we are doing to quit (assuming that we aren't already
  // doing so)
  if (!status && shutdown && interact_style != SmInteractStyleNone) {
    if (self->mClientState != STATE_INTERACTING) {
      SmcInteractRequest(smc_conn, SmDialogNormal,
                         nsNativeAppSupportUnix::InteractCB, client_data);
    }
  } else {
    SmcSaveYourselfDone(smc_conn, True);
  }
}

void
nsNativeAppSupportUnix::DieCB(SmcConn smc_conn, SmPointer client_data)
{
  nsCOMPtr<nsIAppStartup> appService =
    do_GetService("@mozilla.org/toolkit/app-startup;1");

  if (appService) {
    appService->Quit(nsIAppStartup::eForceQuit);
  }
  // Quit causes the shutdown to begin but the shutdown process is asynchronous
  // so we can't DisconnectFromSM() yet
}

void
nsNativeAppSupportUnix::ShutdownCancelledCB(SmcConn smc_conn,
                                            SmPointer client_data)
{
  nsNativeAppSupportUnix *self =
    static_cast<nsNativeAppSupportUnix *>(client_data);

  // Interacting is the only time when we wouldn't already have called
  // SmcSaveYourselfDone. Do that now, then set the state to make sure we
  // don't send it again after finishing interacting
  if (self->mClientState == STATE_INTERACTING) {
    SmcSaveYourselfDone(smc_conn, False);
    self->SetClientState(STATE_SHUTDOWN_CANCELLED);
  }
}

void
nsNativeAppSupportUnix::DisconnectFromSM()
{
  // the SM is free to exit any time after we disconnect, so callers must be
  // sure to have reached a sufficiently advanced phase of shutdown that there
  // is no risk of data loss:
  // e.g. all async writes are complete by the end of "profile-before-change"
  if (mSessionConnection) {
    SetClientState(STATE_DISCONNECTED);
    SmcCloseConnection(mSessionConnection, 0, nullptr);
    mSessionConnection = nullptr;
    gdk_x11_set_sm_client_id(nullptr);  // follow gnome-client behaviour
  }
}

static void
SetSMValue(SmPropValue& val, const nsCString& data)
{
  val.value = static_cast<SmPointer>(const_cast<char*>(data.get()));
  val.length = data.Length();
}

static void
SetSMProperty(SmProp& prop, const char* name, const char* type, int numVals,
              SmPropValue vals[])
{
  prop.name = const_cast<char*>(name);
  prop.type = const_cast<char*>(type);
  prop.num_vals = numVals;
  prop.vals = vals;
}
#endif /* MOZ_X11 */

static void RemoveArg(char **argv)
{
  do {
    *argv = *(argv + 1);
    ++argv;
  } while (*argv);

  --gArgc;
}

NS_IMETHODIMP
nsNativeAppSupportUnix::Start(bool *aRetVal)
{
  NS_ASSERTION(gAppData, "gAppData must not be null.");

// The dbus library is used by both nsWifiScannerDBus and BluetoothDBusService,
// from diffrent threads. This could lead to race conditions if the dbus is not
// initialized before making any other library calls.
#ifdef MOZ_ENABLE_DBUS
  dbus_threads_init_default();
#endif

#if (MOZ_WIDGET_GTK == 2)
  if (gtk_major_version < MIN_GTK_MAJOR_VERSION ||
      (gtk_major_version == MIN_GTK_MAJOR_VERSION && gtk_minor_version < MIN_GTK_MINOR_VERSION)) {
    GtkWidget* versionErrDialog = gtk_message_dialog_new(nullptr,
                     GtkDialogFlags(GTK_DIALOG_MODAL |
                                    GTK_DIALOG_DESTROY_WITH_PARENT),
                     GTK_MESSAGE_ERROR,
                     GTK_BUTTONS_OK,
                     UNSUPPORTED_GTK_MSG,
                     gtk_major_version,
                     gtk_minor_version,
                     MIN_GTK_MAJOR_VERSION,
                     MIN_GTK_MINOR_VERSION);
    gtk_dialog_run(GTK_DIALOG(versionErrDialog));
    gtk_widget_destroy(versionErrDialog);
    MozExpectedExit();
    exit(0);
  }
#endif

  *aRetVal = true;

#ifdef MOZ_X11
  gboolean sm_disable = FALSE;
  if (!getenv("SESSION_MANAGER")) {
    sm_disable = TRUE;
  }

  nsAutoCString prev_client_id;

  char **curarg = gArgv + 1;
  while (*curarg) {
    char *arg = *curarg;
    if (arg[0] == '-' && arg[1] == '-') {
      arg += 2;
      if (!strcmp(arg, "sm-disable")) {
        RemoveArg(curarg);
        sm_disable = TRUE;
        continue;
      } else if (!strcmp(arg, "sm-client-id")) {
        RemoveArg(curarg);
        if (*curarg[0] != '-') {
          prev_client_id = *curarg;
          RemoveArg(curarg);
        }
        continue;
      }
    }

    ++curarg;
  }

  if (prev_client_id.IsEmpty()) {
    prev_client_id = getenv("DESKTOP_AUTOSTART_ID");
  }

  // We don't want child processes to use the same ID
  unsetenv("DESKTOP_AUTOSTART_ID");

  char *client_id = nullptr;
  if (!sm_disable) {
    PRLibrary *iceLib = PR_LoadLibrary("libICE.so.6");
    if (!iceLib) {
      return NS_OK;
    }

    PRLibrary *smLib = PR_LoadLibrary("libSM.so.6");
    if (!smLib) {
      PR_UnloadLibrary(iceLib);
      return NS_OK;
    }

    IceSetIOErrorHandler = (IceSetIOErrorHandlerFn)PR_FindFunctionSymbol(iceLib, "IceSetIOErrorHandler");
    IceAddConnectionWatch = (IceAddConnectionWatchFn)PR_FindFunctionSymbol(iceLib, "IceAddConnectionWatch");
    IceConnectionNumber = (IceConnectionNumberFn)PR_FindFunctionSymbol(iceLib, "IceConnectionNumber");
    IceProcessMessages = (IceProcessMessagesFn)PR_FindFunctionSymbol(iceLib, "IceProcessMessages");
    IceGetConnectionContext = (IceGetConnectionContextFn)PR_FindFunctionSymbol(iceLib, "IceGetConnectionContext");
    if (!IceSetIOErrorHandler || !IceAddConnectionWatch ||
	!IceConnectionNumber  || !IceProcessMessages || !IceGetConnectionContext) {
      PR_UnloadLibrary(iceLib);
      PR_UnloadLibrary(smLib);
      return NS_OK;
    }

    SmcInteractDone = (SmcInteractDoneFn)PR_FindFunctionSymbol(smLib, "SmcInteractDone");
    SmcSaveYourselfDone = (SmcSaveYourselfDoneFn)PR_FindFunctionSymbol(smLib, "SmcSaveYourselfDone");
    SmcInteractRequest = (SmcInteractRequestFn)PR_FindFunctionSymbol(smLib, "SmcInteractRequest");
    SmcCloseConnection = (SmcCloseConnectionFn)PR_FindFunctionSymbol(smLib, "SmcCloseConnection");
    SmcOpenConnection = (SmcOpenConnectionFn)PR_FindFunctionSymbol(smLib, "SmcOpenConnection");
    SmcSetProperties = (SmcSetPropertiesFn)PR_FindFunctionSymbol(smLib, "SmcSetProperties");
    if (!SmcInteractDone || !SmcSaveYourselfDone || !SmcInteractRequest ||
        !SmcCloseConnection || !SmcOpenConnection || !SmcSetProperties) {
      PR_UnloadLibrary(iceLib);
      PR_UnloadLibrary(smLib);
      return NS_OK;
    }

    ice_init();

    // all callbacks are mandatory in libSM 1.0, so listen even if we don't care.
    unsigned long mask = SmcSaveYourselfProcMask | SmcDieProcMask |
                         SmcSaveCompleteProcMask | SmcShutdownCancelledProcMask;

    SmcCallbacks callbacks;
    callbacks.save_yourself.callback = nsNativeAppSupportUnix::SaveYourselfCB;
    callbacks.save_yourself.client_data = static_cast<SmPointer>(this);

    callbacks.die.callback = nsNativeAppSupportUnix::DieCB;
    callbacks.die.client_data = static_cast<SmPointer>(this);

    callbacks.save_complete.callback = nsNativeAppSupportUnix::SaveCompleteCB;
    callbacks.save_complete.client_data = nullptr;

    callbacks.shutdown_cancelled.callback =
      nsNativeAppSupportUnix::ShutdownCancelledCB;
    callbacks.shutdown_cancelled.client_data = static_cast<SmPointer>(this);

    char errbuf[256];
    mSessionConnection = SmcOpenConnection(nullptr, this, SmProtoMajor,
                                           SmProtoMinor, mask, &callbacks,
                                           prev_client_id.get(), &client_id,
                                           sizeof(errbuf), errbuf);
  }

  if (!mSessionConnection) {
    return NS_OK;
  }

  LogModule::Init();  // need to make sure initialized before SetClientState
  if (prev_client_id.IsEmpty() ||
      (client_id && !prev_client_id.Equals(client_id))) {
    SetClientState(STATE_REGISTERING);
  } else {
    SetClientState(STATE_IDLE);
  }

  gdk_x11_set_sm_client_id(client_id);

  // Set SM Properties
  // SmCloneCommand, SmProgram, SmRestartCommand, SmUserID are required
  // properties so must be set, and must have a sensible fallback value.

  // Determine executable path to use for XSMP session restore

  // Is there a request to suppress default binary launcher?
  nsAutoCString path(getenv("MOZ_APP_LAUNCHER"));

  if (path.IsEmpty()) {
    NS_ASSERTION(gDirServiceProvider, "gDirServiceProvider is NULL! This shouldn't happen!");
    nsCOMPtr<nsIFile> executablePath;
    nsresult rv;

    bool dummy;
    rv = gDirServiceProvider->GetFile(XRE_EXECUTABLE_FILE, &dummy, getter_AddRefs(executablePath));

    if (NS_SUCCEEDED(rv)) {
      // Strip off the -bin suffix to get the shell script we should run; this is what Breakpad does
      nsAutoCString leafName;
      rv = executablePath->GetNativeLeafName(leafName);
      if (NS_SUCCEEDED(rv) && StringEndsWith(leafName, NS_LITERAL_CSTRING("-bin"))) {
        leafName.SetLength(leafName.Length() - strlen("-bin"));
        executablePath->SetNativeLeafName(leafName);
      }

      executablePath->GetNativePath(path);
    }
  }

  if (path.IsEmpty()) {
    // can't determine executable path. Best fallback is name from
    // application.ini but it might not resolve to the same executable at
    // launch time.
    path = gAppData->name;  // will always be set
    ToLowerCase(path);
    MOZ_LOG(sMozSMLog, LogLevel::Warning,
        ("Could not determine executable path. Falling back to %s.", path.get()));
  }

  SmProp propRestart, propClone, propProgram, propUser, *props[4];
  SmPropValue valsRestart[3], valsClone[1], valsProgram[1], valsUser[1];
  int n = 0;

  NS_NAMED_LITERAL_CSTRING(kClientIDParam, "--sm-client-id");

  SetSMValue(valsRestart[0], path);
  SetSMValue(valsRestart[1], kClientIDParam);
  SetSMValue(valsRestart[2], nsDependentCString(client_id));
  SetSMProperty(propRestart, SmRestartCommand, SmLISTofARRAY8, 3, valsRestart);
  props[n++] = &propRestart;

  SetSMValue(valsClone[0], path);
  SetSMProperty(propClone, SmCloneCommand, SmLISTofARRAY8, 1, valsClone);
  props[n++] = &propClone;

  nsAutoCString appName(gAppData->name);  // will always be set
  ToLowerCase(appName);

  SetSMValue(valsProgram[0], appName);
  SetSMProperty(propProgram, SmProgram, SmARRAY8, 1, valsProgram);
  props[n++] = &propProgram;

  nsAutoCString userName;  // username that started the program
  struct passwd* pw = getpwuid(getuid());
  if (pw && pw->pw_name) {
    userName = pw->pw_name;
  } else {
    userName = NS_LITERAL_CSTRING("nobody");
    MOZ_LOG(sMozSMLog, LogLevel::Warning,
        ("Could not determine user-name. Falling back to %s.", userName.get()));
  }

  SetSMValue(valsUser[0], userName);
  SetSMProperty(propUser, SmUserID, SmARRAY8, 1, valsUser);
  props[n++] = &propUser;

  SmcSetProperties(mSessionConnection, n, props);

  g_free(client_id);
#endif /* MOZ_X11 */

  return NS_OK;
}

NS_IMETHODIMP
nsNativeAppSupportUnix::Stop(bool *aResult)
{
  NS_ENSURE_ARG(aResult);
  *aResult = true;
  return NS_OK;
}

NS_IMETHODIMP
nsNativeAppSupportUnix::Enable()
{
  return NS_OK;
}

nsresult
NS_CreateNativeAppSupport(nsINativeAppSupport **aResult)
{
  nsNativeAppSupportBase* native = new nsNativeAppSupportUnix();
  if (!native)
    return NS_ERROR_OUT_OF_MEMORY;

  *aResult = native;
  NS_ADDREF(*aResult);

  return NS_OK;
}