DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Header

Mercurial (56e7b9127e89)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433
/* -*- 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
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsDeleteDir.h"
#include "nsIFile.h"
#include "nsString.h"
#include "mozilla/Telemetry.h"
#include "nsITimer.h"
#include "nsISimpleEnumerator.h"
#include "nsAutoPtr.h"
#include "nsThreadUtils.h"
#include "nsISupportsPriority.h"
#include "nsCacheUtils.h"
#include "prtime.h"
#include <time.h>

using namespace mozilla;

class nsBlockOnBackgroundThreadEvent : public Runnable {
public:
  nsBlockOnBackgroundThreadEvent()
    : mozilla::Runnable("nsBlockOnBackgroundThreadEvent")
  {
  }
  NS_IMETHOD Run() override
  {
    MutexAutoLock lock(nsDeleteDir::gInstance->mLock);
    nsDeleteDir::gInstance->mNotified = true;
    nsDeleteDir::gInstance->mCondVar.Notify();
    return NS_OK;
  }
};


nsDeleteDir * nsDeleteDir::gInstance = nullptr;

nsDeleteDir::nsDeleteDir()
  : mLock("nsDeleteDir.mLock"),
    mCondVar(mLock, "nsDeleteDir.mCondVar"),
    mNotified(false),
    mShutdownPending(false),
    mStopDeleting(false)
{
  NS_ASSERTION(gInstance==nullptr, "multiple nsCacheService instances!");
}

nsDeleteDir::~nsDeleteDir()
{
  gInstance = nullptr;
}

nsresult
nsDeleteDir::Init()
{
  if (gInstance)
    return NS_ERROR_ALREADY_INITIALIZED;

  gInstance = new nsDeleteDir();
  return NS_OK;
}

nsresult
nsDeleteDir::Shutdown(bool finishDeleting)
{
  if (!gInstance)
    return NS_ERROR_NOT_INITIALIZED;

  nsCOMArray<nsIFile> dirsToRemove;
  nsCOMPtr<nsIThread> thread;
  {
    MutexAutoLock lock(gInstance->mLock);
    NS_ASSERTION(!gInstance->mShutdownPending,
                 "Unexpected state in nsDeleteDir::Shutdown()");
    gInstance->mShutdownPending = true;

    if (!finishDeleting)
      gInstance->mStopDeleting = true;

    // remove all pending timers
    for (int32_t i = gInstance->mTimers.Count(); i > 0; i--) {
      nsCOMPtr<nsITimer> timer = gInstance->mTimers[i-1];
      gInstance->mTimers.RemoveObjectAt(i-1);

      nsCOMArray<nsIFile> *arg;
      timer->GetClosure((reinterpret_cast<void**>(&arg)));
      timer->Cancel();

      if (finishDeleting)
        dirsToRemove.AppendObjects(*arg);

      // delete argument passed to the timer
      delete arg;
    }

    thread.swap(gInstance->mThread);
    if (thread) {
      // dispatch event and wait for it to run and notify us, so we know thread
      // has completed all work and can be shutdown
      nsCOMPtr<nsIRunnable> event = new nsBlockOnBackgroundThreadEvent();
      nsresult rv = thread->Dispatch(event, NS_DISPATCH_NORMAL);
      if (NS_FAILED(rv)) {
        NS_WARNING("Failed dispatching block-event");
        return NS_ERROR_UNEXPECTED;
      }

      gInstance->mNotified = false;
      while (!gInstance->mNotified) {
        gInstance->mCondVar.Wait();
      }
      nsShutdownThread::BlockingShutdown(thread);
    }
  }

  delete gInstance;

  for (int32_t i = 0; i < dirsToRemove.Count(); i++)
    dirsToRemove[i]->Remove(true);

  return NS_OK;
}

nsresult
nsDeleteDir::InitThread()
{
  if (mThread)
    return NS_OK;

  nsresult rv = NS_NewNamedThread("Cache Deleter", getter_AddRefs(mThread));
  if (NS_FAILED(rv)) {
    NS_WARNING("Can't create background thread");
    return rv;
  }

  nsCOMPtr<nsISupportsPriority> p = do_QueryInterface(mThread);
  if (p) {
    p->SetPriority(nsISupportsPriority::PRIORITY_LOWEST);
  }
  return NS_OK;
}

void
nsDeleteDir::DestroyThread()
{
  if (!mThread)
    return;

  if (mTimers.Count())
    // more work to do, so don't delete thread.
    return;

  nsShutdownThread::Shutdown(mThread);
  mThread = nullptr;
}

void
nsDeleteDir::TimerCallback(nsITimer *aTimer, void *arg)
{
  Telemetry::AutoTimer<Telemetry::NETWORK_DISK_CACHE_DELETEDIR> timer;
  {
    MutexAutoLock lock(gInstance->mLock);

    int32_t idx = gInstance->mTimers.IndexOf(aTimer);
    if (idx == -1) {
      // Timer was canceled and removed during shutdown.
      return;
    }

    gInstance->mTimers.RemoveObjectAt(idx);
  }

  nsAutoPtr<nsCOMArray<nsIFile> > dirList;
  dirList = static_cast<nsCOMArray<nsIFile> *>(arg);

  bool shuttingDown = false;

  // Intentional extra braces to control variable sope.
  {
    // Low IO priority can only be set when running in the context of the
    // current thread.  So this shouldn't be moved to where we set the priority
    // of the Cache deleter thread using the nsThread's NSPR priority constants.
    nsAutoLowPriorityIO autoLowPriority;
    for (int32_t i = 0; i < dirList->Count() && !shuttingDown; i++) {
      gInstance->RemoveDir((*dirList)[i], &shuttingDown);
    }
  }

  {
    MutexAutoLock lock(gInstance->mLock);
    gInstance->DestroyThread();
  }
}

nsresult
nsDeleteDir::DeleteDir(nsIFile *dirIn, bool moveToTrash, uint32_t delay)
{
  Telemetry::AutoTimer<Telemetry::NETWORK_DISK_CACHE_TRASHRENAME> timer;

  if (!gInstance)
    return NS_ERROR_NOT_INITIALIZED;

  nsresult rv;
  nsCOMPtr<nsIFile> trash, dir;

  // Need to make a clone of this since we don't want to modify the input
  // file object.
  rv = dirIn->Clone(getter_AddRefs(dir));
  if (NS_FAILED(rv))
    return rv;

  if (moveToTrash) {
    rv = GetTrashDir(dir, &trash);
    if (NS_FAILED(rv))
      return rv;
    nsAutoCString origLeaf;
    rv = trash->GetNativeLeafName(origLeaf);
    if (NS_FAILED(rv))
      return rv;

    // Append random number to the trash directory and check if it exists.
    srand(static_cast<unsigned>(PR_Now()));
    nsAutoCString leaf;
    for (int32_t i = 0; i < 10; i++) {
      leaf = origLeaf;
      leaf.AppendInt(rand());
      rv = trash->SetNativeLeafName(leaf);
      if (NS_FAILED(rv))
        return rv;

      bool exists;
      if (NS_SUCCEEDED(trash->Exists(&exists)) && !exists) {
        break;
      }

      leaf.Truncate();
    }

    // Fail if we didn't find unused trash directory within the limit
    if (!leaf.Length())
      return NS_ERROR_FAILURE;

#if defined(MOZ_WIDGET_ANDROID)
    nsCOMPtr<nsIFile> parent;
    rv = trash->GetParent(getter_AddRefs(parent));
    if (NS_FAILED(rv))
      return rv;
    rv = dir->MoveToNative(parent, leaf);
#else
    // Important: must rename directory w/o changing parent directory: else on
    // NTFS we'll wait (with cache lock) while nsIFile's ACL reset walks file
    // tree: was hanging GUI for *minutes* on large cache dirs.
    rv = dir->MoveToNative(nullptr, leaf);
#endif
    if (NS_FAILED(rv))
      return rv;
  } else {
    // we want to pass a clone of the original off to the worker thread.
    trash.swap(dir);
  }

  nsAutoPtr<nsCOMArray<nsIFile> > arg(new nsCOMArray<nsIFile>);
  arg->AppendObject(trash);

  rv = gInstance->PostTimer(arg, delay);
  if (NS_FAILED(rv))
    return rv;

  arg.forget();
  return NS_OK;
}

nsresult
nsDeleteDir::GetTrashDir(nsIFile *target, nsCOMPtr<nsIFile> *result)
{
  nsresult rv;
#if defined(MOZ_WIDGET_ANDROID)
  // Try to use the app cache folder for cache trash on Android
  char* cachePath = getenv("CACHE_DIRECTORY");
  if (cachePath) {
    rv = NS_NewNativeLocalFile(nsDependentCString(cachePath),
                               true, getter_AddRefs(*result));
    if (NS_FAILED(rv))
      return rv;

    // Add a sub folder with the cache folder name
    nsAutoCString leaf;
    rv = target->GetNativeLeafName(leaf);
    (*result)->AppendNative(leaf);
  } else
#endif
  {
    rv = target->Clone(getter_AddRefs(*result));
  }
  if (NS_FAILED(rv))
    return rv;

  nsAutoCString leaf;
  rv = (*result)->GetNativeLeafName(leaf);
  if (NS_FAILED(rv))
    return rv;
  leaf.AppendLiteral(".Trash");

  return (*result)->SetNativeLeafName(leaf);
}

nsresult
nsDeleteDir::RemoveOldTrashes(nsIFile *cacheDir)
{
  if (!gInstance)
    return NS_ERROR_NOT_INITIALIZED;

  nsresult rv;

  nsCOMPtr<nsIFile> trash;
  rv = GetTrashDir(cacheDir, &trash);
  if (NS_FAILED(rv))
    return rv;

  nsAutoString trashName;
  rv = trash->GetLeafName(trashName);
  if (NS_FAILED(rv))
    return rv;

  nsCOMPtr<nsIFile> parent;
#if defined(MOZ_WIDGET_ANDROID)
  rv = trash->GetParent(getter_AddRefs(parent));
#else
  rv = cacheDir->GetParent(getter_AddRefs(parent));
#endif
  if (NS_FAILED(rv))
    return rv;

  nsCOMPtr<nsIDirectoryEnumerator> iter;
  rv = parent->GetDirectoryEntries(getter_AddRefs(iter));
  if (NS_FAILED(rv))
    return rv;

  nsAutoPtr<nsCOMArray<nsIFile> > dirList;

  nsCOMPtr<nsIFile> file;
  while (NS_SUCCEEDED(iter->GetNextFile(getter_AddRefs(file))) && file) {
    nsAutoString leafName;
    rv = file->GetLeafName(leafName);
    if (NS_FAILED(rv))
      continue;

    // match all names that begin with the trash name (i.e. "Cache.Trash")
    if (Substring(leafName, 0, trashName.Length()).Equals(trashName)) {
      if (!dirList)
        dirList = new nsCOMArray<nsIFile>;
      dirList->AppendObject(file);
    }
  }

  if (dirList) {
    rv = gInstance->PostTimer(dirList, 90000);
    if (NS_FAILED(rv))
      return rv;

    dirList.forget();
  }

  return NS_OK;
}

nsresult
nsDeleteDir::PostTimer(void *arg, uint32_t delay)
{
  nsresult rv;

  MutexAutoLock lock(mLock);

  rv = InitThread();
  if (NS_FAILED(rv))
    return rv;

  nsCOMPtr<nsITimer> timer;
  rv = NS_NewTimerWithFuncCallback(getter_AddRefs(timer),
                                   TimerCallback,
                                   arg,
                                   delay,
                                   nsITimer::TYPE_ONE_SHOT,
                                   "nsDeleteDir::PostTimer",
                                   mThread);
  if (NS_FAILED(rv))
    return rv;

  mTimers.AppendObject(timer);
  return NS_OK;
}

nsresult
nsDeleteDir::RemoveDir(nsIFile *file, bool *stopDeleting)
{
  nsresult rv;
  bool isLink;

  rv = file->IsSymlink(&isLink);
  if (NS_FAILED(rv) || isLink)
    return NS_ERROR_UNEXPECTED;

  bool isDir;
  rv = file->IsDirectory(&isDir);
  if (NS_FAILED(rv))
    return rv;

  if (isDir) {
    nsCOMPtr<nsIDirectoryEnumerator> iter;
    rv = file->GetDirectoryEntries(getter_AddRefs(iter));
    if (NS_FAILED(rv))
      return rv;

    nsCOMPtr<nsIFile> file2;
    while (NS_SUCCEEDED(iter->GetNextFile(getter_AddRefs(file2))) && file2) {
      RemoveDir(file2, stopDeleting);
      // No check for errors to remove as much as possible

      if (*stopDeleting)
        return NS_OK;
    }
  }

  file->Remove(false);
  // No check for errors to remove as much as possible

  MutexAutoLock lock(mLock);
  if (mStopDeleting)
    *stopDeleting = true;

  return NS_OK;
}