gecko-dev/toolkit/xre/nsNativeAppSupportUnix.cpp
Laurent Bigonville d6b35f20ab Bug 1490059 - Also call "session-save" in the SmSaveGlobal case r=stransky
With modern desktop, the difference between SmSaveGlobal and SmSaveLocal has
faded, moreover the libSM documentation states that: "If save_type is
SmSaveGlobal the user wants the client to commit all of its data to permanent,
globally accessible storage.", it's difficult to understand why firefox
wouldn't save its session state in that case.

gnome-session is using SmSaveGlobal when closing the user session, that means
that under GNOME, firefox blocks the closing of the session and complains that
it has crashed on restart.

With this patch, "session-save" is sent in all cases, that means that the two
issues noted in the original bug are fixed.

Differential Revision: https://phabricator.services.mozilla.com/D47500

--HG--
extra : moz-landing-system : lando
2019-10-01 10:32:09 +00:00

663 lines
22 KiB
C++

/* -*- 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) override;
NS_IMETHOD Enable() override;
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("nsNativeAppSupportUnix::DoInteract", 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;
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
*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(
gArgc, gArgv); // 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::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;
}