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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* 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
#include "nsUpdateSyncManager.h"
#include "mozilla/Unused.h"
#include "mozilla/Services.h"
#include "nsComponentManagerUtils.h"
#include "nsCRT.h"
#include "nsIFile.h"
#include "nsIObserverService.h"
#include "nsIProperties.h"
#include "nsString.h"
#include "nsXULAppAPI.h"
// The lock code generates a path that already includes the vendor name,
// so this only needs to name the specific lock.
#define UPDATE_LOCK_NAME_TOKEN "UpdateLock"
nsUpdateSyncManager* gUpdateSyncManager = nullptr;
NS_IMPL_ISUPPORTS(nsUpdateSyncManager, nsIUpdateSyncManager, nsIObserver)
nsUpdateSyncManager::nsUpdateSyncManager(nsIFile* anAppFile /* = nullptr */) {
gUpdateSyncManager = this;
OpenLock(anAppFile);
}
nsUpdateSyncManager::~nsUpdateSyncManager() {
ReleaseLock();
gUpdateSyncManager = nullptr;
}
already_AddRefed<nsUpdateSyncManager> nsUpdateSyncManager::GetSingleton() {
if (!gUpdateSyncManager) {
new nsUpdateSyncManager(); // This sets gUpdateSyncManager.
}
return do_AddRef(gUpdateSyncManager);
}
NS_IMETHODIMP nsUpdateSyncManager::Observe(nsISupports* aSubject,
const char* aTopic,
const char16_t* aData) {
mozilla::Unused << aSubject;
mozilla::Unused << aData;
// We want to hold the lock for as much of the lifetime of the app as we can,
// so we observe xpcom-startup so we get constructed as early as possible,
// which triggers constructing the singleton.
if (!nsCRT::strcmp(aTopic, NS_XPCOM_STARTUP_OBSERVER_ID)) {
nsCOMPtr<nsIObserverService> observerService =
mozilla::services::GetObserverService();
if (observerService) {
return observerService->AddObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID,
false);
}
return NS_ERROR_SERVICE_NOT_AVAILABLE;
}
if (!nsCRT::strcmp(aTopic, NS_XPCOM_SHUTDOWN_OBSERVER_ID)) {
ReleaseLock();
}
return NS_OK;
}
nsresult nsUpdateSyncManager::OpenLock(nsIFile* anAppFile) {
nsresult rv;
if (mLock != MULTI_INSTANCE_LOCK_HANDLE_ERROR) {
// Lock is already open.
return NS_OK;
}
// Our component registration should already have made sure of this.
if (NS_WARN_IF(XRE_GetProcessType() != GeckoProcessType_Default)) {
return NS_OK;
}
nsCOMPtr<nsIFile> appFile = mozilla::GetNormalizedAppFile(anAppFile);
if (!appFile) {
return NS_ERROR_NOT_AVAILABLE;
}
nsCOMPtr<nsIFile> appDirFile;
rv = appFile->GetParent(getter_AddRefs(appDirFile));
NS_ENSURE_SUCCESS(rv, rv);
nsAutoString appDirPath;
rv = appDirFile->GetPath(appDirPath);
NS_ENSURE_SUCCESS(rv, rv);
mLock =
mozilla::OpenMultiInstanceLock(UPDATE_LOCK_NAME_TOKEN, appDirPath.get());
NS_ENSURE_TRUE(mLock, NS_ERROR_FAILURE);
return NS_OK;
}
void nsUpdateSyncManager::ReleaseLock() {
if (mLock == MULTI_INSTANCE_LOCK_HANDLE_ERROR) {
// Lock is already released.
return;
}
mozilla::ReleaseMultiInstanceLock(mLock);
mLock = MULTI_INSTANCE_LOCK_HANDLE_ERROR;
}
NS_IMETHODIMP nsUpdateSyncManager::IsOtherInstanceRunning(bool* aResult) {
if (NS_WARN_IF(XRE_GetProcessType() != GeckoProcessType_Default)) {
return NS_ERROR_SERVICE_NOT_AVAILABLE;
}
if (mLock == MULTI_INSTANCE_LOCK_HANDLE_ERROR) {
return NS_ERROR_NOT_INITIALIZED;
}
bool rv = mozilla::IsOtherInstanceRunning(mLock, aResult);
NS_ENSURE_TRUE(rv, NS_ERROR_FAILURE);
return NS_OK;
}
NS_IMETHODIMP nsUpdateSyncManager::ResetLock(nsIFile* anAppFile = nullptr) {
ReleaseLock();
return OpenLock(anAppFile);
}