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/* -*- 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 "TemporaryAccessGrantObserver.h"
#include "mozilla/AppShutdown.h"
#include "mozilla/ClearOnShutdown.h"
#include "mozilla/PermissionManager.h"
#include "mozilla/Services.h"
#include "nsIObserverService.h"
#include "nsTHashtable.h"
#include "nsXULAppAPI.h"
using namespace mozilla;
StaticAutoPtr<TemporaryAccessGrantObserver::ObserversTable>
TemporaryAccessGrantObserver::sObservers;
TemporaryAccessGrantObserver::TemporaryAccessGrantObserver(
PermissionManager* aPM, nsIPrincipal* aPrincipal, const nsACString& aType)
: mPM(aPM), mPrincipal(aPrincipal), mType(aType) {
MOZ_ASSERT(XRE_IsParentProcess(),
"Enforcing temporary access grant lifetimes can only be done in "
"the parent process");
}
NS_IMPL_ISUPPORTS(TemporaryAccessGrantObserver, nsIObserver, nsINamed)
// static
void TemporaryAccessGrantObserver::Create(PermissionManager* aPM,
nsIPrincipal* aPrincipal,
const nsACString& aType) {
MOZ_ASSERT(XRE_IsParentProcess());
MOZ_ASSERT(NS_IsMainThread());
if (!sObservers) {
// Prevent us from resurrection during shutdown. Note that ClearOnShutdown
// would kill us right away in this case, but we want to return with no-op.
if (AppShutdown::IsInOrBeyond(ShutdownPhase::XPCOMWillShutdown)) {
return;
}
sObservers = new ObserversTable();
// PermissionManager shuts down in this phase, so we should avoid to keep
// references to it for longer. Clearing will cancel all outstanding timers
// and clear the table. This is safe as the timers have been created from
// and target to the main thread (so we do not need an explicit Cancel).
ClearOnShutdown(&sObservers, ShutdownPhase::XPCOMWillShutdown);
}
sObservers->LookupOrInsertWith(
std::make_pair(nsCOMPtr<nsIPrincipal>(aPrincipal), nsCString(aType)),
[&]() -> nsCOMPtr<nsITimer> {
// Only create a new observer if we don't have a matching
// entry in our hashtable.
nsCOMPtr<nsITimer> timer;
RefPtr<TemporaryAccessGrantObserver> observer =
new TemporaryAccessGrantObserver(aPM, aPrincipal, aType);
nsresult rv = NS_NewTimerWithObserver(getter_AddRefs(timer), observer,
24 * 60 * 60 * 1000, // 24 hours
nsITimer::TYPE_ONE_SHOT);
if (NS_SUCCEEDED(rv)) {
observer->SetTimer(timer);
return timer;
}
timer->Cancel();
return nullptr;
});
}
void TemporaryAccessGrantObserver::SetTimer(nsITimer* aTimer) {
mTimer = aTimer;
}
NS_IMETHODIMP
TemporaryAccessGrantObserver::Observe(nsISupports* aSubject, const char* aTopic,
const char16_t* aData) {
if (strcmp(aTopic, NS_TIMER_CALLBACK_TOPIC) == 0) {
Unused << mPM->RemoveFromPrincipal(mPrincipal, mType);
MOZ_ASSERT(sObservers);
sObservers->Remove(std::make_pair(mPrincipal, mType));
}
return NS_OK;
}
NS_IMETHODIMP
TemporaryAccessGrantObserver::GetName(nsACString& aName) {
aName.AssignLiteral("TemporaryAccessGrantObserver");
return NS_OK;
}