Quelle RLBoxSandboxPool.cpp Sprache: 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 "nsThreadUtils.h"
#include "mozilla/ClearOnShutdown.h"
#include "mozilla/DebugOnly.h"
#include "mozilla/RLBoxSandboxPool.h"
#ifdef MOZ_USING_WASM_SANDBOXING
#  include "wasm2c_rt_mem.h"
#endif

using namespace mozilla;

NS_IMPL_ISUPPORTS(RLBoxSandboxPool, nsITimerCallback, nsINamed)

void RLBoxSandboxPool::StartTimer() {
  mMutex.AssertCurrentThreadOwns();
  MOZ_ASSERT(!mTimer, "timer already initialized");
  if (NS_IsMainThread() &&
      PastShutdownPhase(ShutdownPhase::AppShutdownConfirmed)) {
    // If we're shutting down, setting the time might fail, and we don't need it
    // (since all the memory will be cleaned up soon anyway). Note that
    // PastShutdownPhase() can only be called on the main thread, but that's
    // fine, because other threads will have joined already by the point timers
    // start failing to register.
    mPool.Clear();
    return;
  }
  DebugOnly<nsresult> rv = NS_NewTimerWithCallback(
      getter_AddRefs(mTimer), this, mDelaySeconds * 1000,
      nsITimer::TYPE_ONE_SHOT, GetMainThreadSerialEventTarget());
  MOZ_ASSERT(NS_SUCCEEDED(rv), "failed to create timer");
}

void RLBoxSandboxPool::CancelTimer() {
  mMutex.AssertCurrentThreadOwns();
  if (mTimer) {
    mTimer->Cancel();
    mTimer = nullptr;
  }
}

NS_IMETHODIMP RLBoxSandboxPool::Notify(nsITimer* aTimer) {
  MutexAutoLock lock(mMutex);

  mPool.Clear();
  mTimer = nullptr;

  return NS_OK;
}

NS_IMETHODIMP RLBoxSandboxPool::GetName(nsACString& aName) {
  aName.AssignLiteral("RLBoxSandboxPool");
  return NS_OK;
}

void RLBoxSandboxPool::Push(UniquePtr<RLBoxSandboxDataBase> sbxData) {
  MutexAutoLock lock(mMutex);

  mPool.AppendElement(std::move(sbxData));
  if (!mTimer) {
    StartTimer();
  }
}

UniquePtr<RLBoxSandboxPoolData> RLBoxSandboxPool::PopOrCreate(
    uint64_t aMinSize) {
  MutexAutoLock lock(mMutex);

  UniquePtr<RLBoxSandboxDataBase> sbxData;

  if (!mPool.IsEmpty()) {
    const int64_t lastIndex = ReleaseAssertedCast<int64_t>(mPool.Length()) - 1;
    for (int64_t i = lastIndex; i >= 0; i--) {
      if (mPool[i]->mSize >= aMinSize) {
        sbxData = std::move(mPool[i]);
        mPool.RemoveElementAt(i);

        // If we reuse a sandbox from the pool, reset the timer to clear the
        // pool
        CancelTimer();
        if (!mPool.IsEmpty()) {
          StartTimer();
        }
        break;
      }
    }
  }

  if (!sbxData) {
#ifdef MOZ_USING_WASM_SANDBOXING
    // RLBox's wasm sandboxes have a limited platform dependent capacity. We
    // track this capacity in this pool.
    const w2c_mem_capacity w2c_capacity = get_valid_wasm2c_memory_capacity(
        aMinSize, true /* 32-bit wasm memory*/);
    const uint64_t chosenCapacity = w2c_capacity.max_size;
#else
    // Note the noop sandboxes have no capacity limit. In this case we simply
    // specify a value of 4gb. This is not actually enforced by the noop
    // sandbox.
    const uint64_t chosenCapacity = static_cast<uint64_t>(1) << 32;
#endif
    sbxData = CreateSandboxData(chosenCapacity);
    NS_ENSURE_TRUE(sbxData, nullptr);
  }

  return MakeUnique<RLBoxSandboxPoolData>(std::move(sbxData), this);
}

quality93%

¤ Dauer der Verarbeitung: 0.14 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.

Bemerkung:

Die farbliche Syntaxdarstellung ist noch experimentell.