netwerk/cache/nsDiskCacheDeviceSQL.cpp

/* -*- Mode: C++; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cin: */
/* 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 <inttypes.h>

#include "mozilla/ArrayUtils.h"
#include "mozilla/Attributes.h"
#include "mozilla/Sprintf.h"
#include "mozilla/ThreadLocal.h"

#include "nsCache.h"
#include "nsDiskCache.h"
#include "nsDiskCacheDeviceSQL.h"
#include "nsCacheService.h"
#include "nsApplicationCache.h"
#include "../cache2/CacheHashUtils.h"

#include "nsNetCID.h"
#include "nsNetUtil.h"
#include "nsIURI.h"
#include "nsEscape.h"
#include "nsIPrefBranch.h"
#include "nsString.h"
#include "nsPrintfCString.h"
#include "nsCRT.h"
#include "nsArrayUtils.h"
#include "nsIArray.h"
#include "nsIVariant.h"
#include "nsILoadContextInfo.h"
#include "nsThreadUtils.h"
#include "nsISerializable.h"
#include "nsIInputStream.h"
#include "nsIOutputStream.h"
#include "nsSerializationHelper.h"
#include "nsMemory.h"

#include "mozIStorageService.h"
#include "mozIStorageStatement.h"
#include "mozIStorageFunction.h"
#include "mozStorageHelper.h"

#include "nsICacheVisitor.h"
#include "nsISeekableStream.h"

#include "mozilla/Telemetry.h"

#include "mozilla/storage.h"
#include "nsVariant.h"
#include "mozilla/BasePrincipal.h"

using namespace mozilla;
using namespace mozilla::storage;
using mozilla::OriginAttributes;

static const char OFFLINE_CACHE_DEVICE_ID[] = {"offline"};

#define LOG(args) CACHE_LOG_DEBUG(args)

static uint32_t gNextTemporaryClientID = 0;

/*****************************************************************************
 * helpers
 */

static nsresult EnsureDir(nsIFile* dir) {
  bool exists;
  nsresult rv = dir->Exists(&exists);
  if (NS_SUCCEEDED(rv) && !exists)
    rv = dir->Create(nsIFile::DIRECTORY_TYPE, 0700);
  return rv;
}

static bool DecomposeCacheEntryKey(const nsCString* fullKey, const char** cid,
                                   const char** key, nsCString& buf) {
  buf = *fullKey;

  int32_t colon = buf.FindChar(':');
  if (colon == kNotFound) {
    NS_ERROR("Invalid key");
    return false;
  }
  buf.SetCharAt('\0', colon);

  *cid = buf.get();
  *key = buf.get() + colon + 1;

  return true;
}

class AutoResetStatement {
 public:
  explicit AutoResetStatement(mozIStorageStatement* s) : mStatement(s) {}
  ~AutoResetStatement() { mStatement->Reset(); }
  mozIStorageStatement* operator->() MOZ_NO_ADDREF_RELEASE_ON_RETURN {
    return mStatement;
  }

 private:
  mozIStorageStatement* mStatement;
};

class EvictionObserver {
 public:
  EvictionObserver(mozIStorageConnection* db,
                   nsOfflineCacheEvictionFunction* evictionFunction)
      : mDB(db), mEvictionFunction(evictionFunction) {
    mEvictionFunction->Init();
    mDB->ExecuteSimpleSQL(
        NS_LITERAL_CSTRING("CREATE TEMP TRIGGER cache_on_delete BEFORE DELETE"
                           " ON moz_cache FOR EACH ROW BEGIN SELECT"
                           " cache_eviction_observer("
                           "  OLD.ClientID, OLD.key, OLD.generation);"
                           " END;"));
  }

  ~EvictionObserver() {
    mDB->ExecuteSimpleSQL(NS_LITERAL_CSTRING("DROP TRIGGER cache_on_delete;"));
    mEvictionFunction->Reset();
  }

  void Apply() { return mEvictionFunction->Apply(); }

 private:
  mozIStorageConnection* mDB;
  RefPtr<nsOfflineCacheEvictionFunction> mEvictionFunction;
};

#define DCACHE_HASH_MAX INT64_MAX
#define DCACHE_HASH_BITS 64

/**
 *  nsOfflineCache::Hash(const char * key)
 *
 *  This algorithm of this method implies nsOfflineCacheRecords will be stored
 *  in a certain order on disk.  If the algorithm changes, existing cache
 *  map files may become invalid, and therefore the kCurrentVersion needs
 *  to be revised.
 */
static uint64_t DCacheHash(const char* key) {
  // initval 0x7416f295 was chosen randomly
  return (uint64_t(CacheHash::Hash(key, strlen(key), 0)) << 32) |
         CacheHash::Hash(key, strlen(key), 0x7416f295);
}

/******************************************************************************
 * nsOfflineCacheEvictionFunction
 */

NS_IMPL_ISUPPORTS(nsOfflineCacheEvictionFunction, mozIStorageFunction)

// helper function for directly exposing the same data file binding
// path algorithm used in nsOfflineCacheBinding::Create
static nsresult GetCacheDataFile(nsIFile* cacheDir, const char* key,
                                 int generation, nsCOMPtr<nsIFile>& file) {
  cacheDir->Clone(getter_AddRefs(file));
  if (!file) return NS_ERROR_OUT_OF_MEMORY;

  uint64_t hash = DCacheHash(key);

  uint32_t dir1 = (uint32_t)(hash & 0x0F);
  uint32_t dir2 = (uint32_t)((hash & 0xF0) >> 4);

  hash >>= 8;

  file->AppendNative(nsPrintfCString("%X", dir1));
  file->AppendNative(nsPrintfCString("%X", dir2));

  char leaf[64];
  SprintfLiteral(leaf, "%014" PRIX64 "-%X", hash, generation);
  return file->AppendNative(nsDependentCString(leaf));
}

namespace appcachedetail {

typedef nsCOMArray<nsIFile> FileArray;
static MOZ_THREAD_LOCAL(FileArray*) tlsEvictionItems;

}  // namespace appcachedetail

NS_IMETHODIMP
nsOfflineCacheEvictionFunction::OnFunctionCall(mozIStorageValueArray* values,
                                               nsIVariant** _retval) {
  LOG(("nsOfflineCacheEvictionFunction::OnFunctionCall\n"));

  *_retval = nullptr;

  uint32_t numEntries;
  nsresult rv = values->GetNumEntries(&numEntries);
  NS_ENSURE_SUCCESS(rv, rv);
  NS_ASSERTION(numEntries == 3, "unexpected number of arguments");

  uint32_t valueLen;
  const char* clientID = values->AsSharedUTF8String(0, &valueLen);
  const char* key = values->AsSharedUTF8String(1, &valueLen);
  nsAutoCString fullKey(clientID);
  fullKey.Append(':');
  fullKey.Append(key);
  int generation = values->AsInt32(2);

  // If the key is currently locked, refuse to delete this row.
  if (mDevice->IsLocked(fullKey)) {
    // This code thought it was performing the equivalent of invoking the SQL
    // "RAISE(IGNORE)" function.  It was not.  Please see bug 1470961 and any
    // follow-ups to understand the plan for correcting this bug.
    return NS_OK;
  }

  nsCOMPtr<nsIFile> file;
  rv = GetCacheDataFile(mDevice->CacheDirectory(), key, generation, file);
  if (NS_FAILED(rv)) {
    LOG(("GetCacheDataFile [key=%s generation=%d] failed [rv=%" PRIx32 "]!\n",
         key, generation, static_cast<uint32_t>(rv)));
    return rv;
  }

  appcachedetail::FileArray* items = appcachedetail::tlsEvictionItems.get();
  MOZ_ASSERT(items);
  if (items) {
    items->AppendObject(file);
  }

  return NS_OK;
}

nsOfflineCacheEvictionFunction::nsOfflineCacheEvictionFunction(
    nsOfflineCacheDevice* device)
    : mDevice(device) {
  mTLSInited = appcachedetail::tlsEvictionItems.init();
}

void nsOfflineCacheEvictionFunction::Init() {
  if (mTLSInited) {
    appcachedetail::tlsEvictionItems.set(new appcachedetail::FileArray());
  }
}

void nsOfflineCacheEvictionFunction::Reset() {
  if (!mTLSInited) {
    return;
  }

  appcachedetail::FileArray* items = appcachedetail::tlsEvictionItems.get();
  if (!items) {
    return;
  }

  appcachedetail::tlsEvictionItems.set(nullptr);
  delete items;
}

void nsOfflineCacheEvictionFunction::Apply() {
  LOG(("nsOfflineCacheEvictionFunction::Apply\n"));

  if (!mTLSInited) {
    return;
  }

  appcachedetail::FileArray* pitems = appcachedetail::tlsEvictionItems.get();
  if (!pitems) {
    return;
  }

  appcachedetail::FileArray items;
  items.SwapElements(*pitems);

  for (int32_t i = 0; i < items.Count(); i++) {
    if (MOZ_LOG_TEST(gCacheLog, LogLevel::Debug)) {
      LOG(("  removing %s\n", items[i]->HumanReadablePath().get()));
    }

    items[i]->Remove(false);
  }
}

class nsOfflineCacheDiscardCache : public Runnable {
 public:
  nsOfflineCacheDiscardCache(nsOfflineCacheDevice* device, nsCString& group,
                             nsCString& clientID)
      : mozilla::Runnable("nsOfflineCacheDiscardCache"),
        mDevice(device),
        mGroup(group),
        mClientID(clientID) {}

  NS_IMETHOD Run() override {
    if (mDevice->IsActiveCache(mGroup, mClientID)) {
      mDevice->DeactivateGroup(mGroup);
    }

    return mDevice->EvictEntries(mClientID.get());
  }

 private:
  RefPtr<nsOfflineCacheDevice> mDevice;
  nsCString mGroup;
  nsCString mClientID;
};

/******************************************************************************
 * nsOfflineCacheDeviceInfo
 */

class nsOfflineCacheDeviceInfo final : public nsICacheDeviceInfo {
 public:
  NS_DECL_ISUPPORTS
  NS_DECL_NSICACHEDEVICEINFO

  explicit nsOfflineCacheDeviceInfo(nsOfflineCacheDevice* device)
      : mDevice(device) {}

 private:
  ~nsOfflineCacheDeviceInfo() = default;

  nsOfflineCacheDevice* mDevice;
};

NS_IMPL_ISUPPORTS(nsOfflineCacheDeviceInfo, nsICacheDeviceInfo)

NS_IMETHODIMP
nsOfflineCacheDeviceInfo::GetDescription(nsACString& aDescription) {
  aDescription.AssignLiteral("Offline cache device");
  return NS_OK;
}

NS_IMETHODIMP
nsOfflineCacheDeviceInfo::GetUsageReport(nsACString& aUsageReport) {
  nsAutoCString buffer;
  buffer.AssignLiteral(
      "  <tr>\n"
      "    <th>Cache Directory:</th>\n"
      "    <td>");
  nsIFile* cacheDir = mDevice->CacheDirectory();
  if (!cacheDir) return NS_OK;

  nsAutoString path;
  nsresult rv = cacheDir->GetPath(path);
  if (NS_SUCCEEDED(rv))
    AppendUTF16toUTF8(path, buffer);
  else
    buffer.AppendLiteral("directory unavailable");

  buffer.AppendLiteral(
      "</td>\n"
      "  </tr>\n");

  aUsageReport.Assign(buffer);
  return NS_OK;
}

NS_IMETHODIMP
nsOfflineCacheDeviceInfo::GetEntryCount(uint32_t* aEntryCount) {
  *aEntryCount = mDevice->EntryCount();
  return NS_OK;
}

NS_IMETHODIMP
nsOfflineCacheDeviceInfo::GetTotalSize(uint32_t* aTotalSize) {
  *aTotalSize = mDevice->CacheSize();
  return NS_OK;
}

NS_IMETHODIMP
nsOfflineCacheDeviceInfo::GetMaximumSize(uint32_t* aMaximumSize) {
  *aMaximumSize = mDevice->CacheCapacity();
  return NS_OK;
}

/******************************************************************************
 * nsOfflineCacheBinding
 */

class nsOfflineCacheBinding final : public nsISupports {
  ~nsOfflineCacheBinding() = default;

 public:
  NS_DECL_THREADSAFE_ISUPPORTS

  static nsOfflineCacheBinding* Create(nsIFile* cacheDir, const nsCString* key,
                                       int generation);

  enum { FLAG_NEW_ENTRY = 1 };

  nsCOMPtr<nsIFile> mDataFile;
  int mGeneration;
  int mFlags;

  bool IsNewEntry() { return mFlags & FLAG_NEW_ENTRY; }
  void MarkNewEntry() { mFlags |= FLAG_NEW_ENTRY; }
  void ClearNewEntry() { mFlags &= ~FLAG_NEW_ENTRY; }
};

NS_IMPL_ISUPPORTS0(nsOfflineCacheBinding)

nsOfflineCacheBinding* nsOfflineCacheBinding::Create(nsIFile* cacheDir,
                                                     const nsCString* fullKey,
                                                     int generation) {
  nsCOMPtr<nsIFile> file;
  cacheDir->Clone(getter_AddRefs(file));
  if (!file) return nullptr;

  nsAutoCString keyBuf;
  const char *cid, *key;
  if (!DecomposeCacheEntryKey(fullKey, &cid, &key, keyBuf)) return nullptr;

  uint64_t hash = DCacheHash(key);

  uint32_t dir1 = (uint32_t)(hash & 0x0F);
  uint32_t dir2 = (uint32_t)((hash & 0xF0) >> 4);

  hash >>= 8;

  // XXX we might want to create these directories up-front

  file->AppendNative(nsPrintfCString("%X", dir1));
  Unused << file->Create(nsIFile::DIRECTORY_TYPE, 00700);

  file->AppendNative(nsPrintfCString("%X", dir2));
  Unused << file->Create(nsIFile::DIRECTORY_TYPE, 00700);

  nsresult rv;
  char leaf[64];

  if (generation == -1) {
    file->AppendNative(NS_LITERAL_CSTRING("placeholder"));

    for (generation = 0;; ++generation) {
      SprintfLiteral(leaf, "%014" PRIX64 "-%X", hash, generation);

      rv = file->SetNativeLeafName(nsDependentCString(leaf));
      if (NS_FAILED(rv)) return nullptr;
      rv = file->Create(nsIFile::NORMAL_FILE_TYPE, 00600);
      if (NS_FAILED(rv) && rv != NS_ERROR_FILE_ALREADY_EXISTS) return nullptr;
      if (NS_SUCCEEDED(rv)) break;
    }
  } else {
    SprintfLiteral(leaf, "%014" PRIX64 "-%X", hash, generation);
    rv = file->AppendNative(nsDependentCString(leaf));
    if (NS_FAILED(rv)) return nullptr;
  }

  nsOfflineCacheBinding* binding = new nsOfflineCacheBinding;
  if (!binding) return nullptr;

  binding->mDataFile.swap(file);
  binding->mGeneration = generation;
  binding->mFlags = 0;
  return binding;
}

/******************************************************************************
 * nsOfflineCacheRecord
 */

struct nsOfflineCacheRecord {
  const char* clientID;
  const char* key;
  const uint8_t* metaData;
  uint32_t metaDataLen;
  int32_t generation;
  int32_t dataSize;
  int32_t fetchCount;
  int64_t lastFetched;
  int64_t lastModified;
  int64_t expirationTime;
};

static nsCacheEntry* CreateCacheEntry(nsOfflineCacheDevice* device,
                                      const nsCString* fullKey,
                                      const nsOfflineCacheRecord& rec) {
  nsCacheEntry* entry;

  if (device->IsLocked(*fullKey)) {
    return nullptr;
  }

  nsresult rv = nsCacheEntry::Create(fullKey->get(),  // XXX enable sharing
                                     nsICache::STREAM_BASED,
                                     nsICache::STORE_OFFLINE, device, &entry);
  if (NS_FAILED(rv)) return nullptr;

  entry->SetFetchCount((uint32_t)rec.fetchCount);
  entry->SetLastFetched(SecondsFromPRTime(rec.lastFetched));
  entry->SetLastModified(SecondsFromPRTime(rec.lastModified));
  entry->SetExpirationTime(SecondsFromPRTime(rec.expirationTime));
  entry->SetDataSize((uint32_t)rec.dataSize);

  entry->UnflattenMetaData((const char*)rec.metaData, rec.metaDataLen);

  // Restore security info, if present
  const char* info = entry->GetMetaDataElement("security-info");
  if (info) {
    nsCOMPtr<nsISupports> infoObj;
    rv =
        NS_DeserializeObject(nsDependentCString(info), getter_AddRefs(infoObj));
    if (NS_FAILED(rv)) {
      delete entry;
      return nullptr;
    }
    entry->SetSecurityInfo(infoObj);
  }

  // create a binding object for this entry
  nsOfflineCacheBinding* binding = nsOfflineCacheBinding::Create(
      device->CacheDirectory(), fullKey, rec.generation);
  if (!binding) {
    delete entry;
    return nullptr;
  }
  entry->SetData(binding);

  return entry;
}

/******************************************************************************
 * nsOfflineCacheEntryInfo
 */

class nsOfflineCacheEntryInfo final : public nsICacheEntryInfo {
  ~nsOfflineCacheEntryInfo() = default;

 public:
  NS_DECL_ISUPPORTS
  NS_DECL_NSICACHEENTRYINFO

  nsOfflineCacheRecord* mRec;
};

NS_IMPL_ISUPPORTS(nsOfflineCacheEntryInfo, nsICacheEntryInfo)

NS_IMETHODIMP
nsOfflineCacheEntryInfo::GetClientID(nsACString& aClientID) {
  aClientID.Assign(mRec->clientID);
  return NS_OK;
}

NS_IMETHODIMP
nsOfflineCacheEntryInfo::GetDeviceID(nsACString& aDeviceID) {
  aDeviceID.Assign(OFFLINE_CACHE_DEVICE_ID);
  return NS_OK;
}

NS_IMETHODIMP
nsOfflineCacheEntryInfo::GetKey(nsACString& clientKey) {
  clientKey.Assign(mRec->key);
  return NS_OK;
}

NS_IMETHODIMP
nsOfflineCacheEntryInfo::GetFetchCount(int32_t* aFetchCount) {
  *aFetchCount = mRec->fetchCount;
  return NS_OK;
}

NS_IMETHODIMP
nsOfflineCacheEntryInfo::GetLastFetched(uint32_t* aLastFetched) {
  *aLastFetched = SecondsFromPRTime(mRec->lastFetched);
  return NS_OK;
}

NS_IMETHODIMP
nsOfflineCacheEntryInfo::GetLastModified(uint32_t* aLastModified) {
  *aLastModified = SecondsFromPRTime(mRec->lastModified);
  return NS_OK;
}

NS_IMETHODIMP
nsOfflineCacheEntryInfo::GetExpirationTime(uint32_t* aExpirationTime) {
  *aExpirationTime = SecondsFromPRTime(mRec->expirationTime);
  return NS_OK;
}

NS_IMETHODIMP
nsOfflineCacheEntryInfo::IsStreamBased(bool* aStreamBased) {
  *aStreamBased = true;
  return NS_OK;
}

NS_IMETHODIMP
nsOfflineCacheEntryInfo::GetDataSize(uint32_t* aDataSize) {
  *aDataSize = mRec->dataSize;
  return NS_OK;
}

/******************************************************************************
 * nsApplicationCacheNamespace
 */

NS_IMPL_ISUPPORTS(nsApplicationCacheNamespace, nsIApplicationCacheNamespace)

NS_IMETHODIMP
nsApplicationCacheNamespace::Init(uint32_t itemType,
                                  const nsACString& namespaceSpec,
                                  const nsACString& data) {
  mItemType = itemType;
  mNamespaceSpec = namespaceSpec;
  mData = data;
  return NS_OK;
}

NS_IMETHODIMP
nsApplicationCacheNamespace::GetItemType(uint32_t* out) {
  *out = mItemType;
  return NS_OK;
}

NS_IMETHODIMP
nsApplicationCacheNamespace::GetNamespaceSpec(nsACString& out) {
  out = mNamespaceSpec;
  return NS_OK;
}

NS_IMETHODIMP
nsApplicationCacheNamespace::GetData(nsACString& out) {
  out = mData;
  return NS_OK;
}

/******************************************************************************
 * nsApplicationCache
 */

NS_IMPL_ISUPPORTS(nsApplicationCache, nsIApplicationCache,
                  nsISupportsWeakReference)

nsApplicationCache::nsApplicationCache() : mDevice(nullptr), mValid(true) {}

nsApplicationCache::nsApplicationCache(nsOfflineCacheDevice* device,
                                       const nsACString& group,
                                       const nsACString& clientID)
    : mDevice(device), mGroup(group), mClientID(clientID), mValid(true) {}

nsApplicationCache::~nsApplicationCache() {
  if (!mDevice) return;

  {
    MutexAutoLock lock(mDevice->mLock);
    mDevice->mCaches.Remove(mClientID);
  }

  // If this isn't an active cache anymore, it can be destroyed.
  if (mValid && !mDevice->IsActiveCache(mGroup, mClientID)) Discard();
}

void nsApplicationCache::MarkInvalid() { mValid = false; }

NS_IMETHODIMP
nsApplicationCache::InitAsHandle(const nsACString& groupId,
                                 const nsACString& clientId) {
  NS_ENSURE_FALSE(mDevice, NS_ERROR_ALREADY_INITIALIZED);
  NS_ENSURE_TRUE(mGroup.IsEmpty(), NS_ERROR_ALREADY_INITIALIZED);

  mGroup = groupId;
  mClientID = clientId;
  return NS_OK;
}

NS_IMETHODIMP
nsApplicationCache::GetManifestURI(nsIURI** out) {
  nsCOMPtr<nsIURI> uri;
  nsresult rv = NS_NewURI(getter_AddRefs(uri), mGroup);
  NS_ENSURE_SUCCESS(rv, rv);

  rv = NS_GetURIWithNewRef(uri, EmptyCString(), out);
  NS_ENSURE_SUCCESS(rv, rv);

  return NS_OK;
}

NS_IMETHODIMP
nsApplicationCache::GetGroupID(nsACString& out) {
  out = mGroup;
  return NS_OK;
}

NS_IMETHODIMP
nsApplicationCache::GetClientID(nsACString& out) {
  out = mClientID;
  return NS_OK;
}

NS_IMETHODIMP
nsApplicationCache::GetProfileDirectory(nsIFile** out) {
  *out = do_AddRef(mDevice->BaseDirectory()).take();
  return NS_OK;
}

NS_IMETHODIMP
nsApplicationCache::GetActive(bool* out) {
  NS_ENSURE_TRUE(mDevice, NS_ERROR_NOT_AVAILABLE);

  *out = mDevice->IsActiveCache(mGroup, mClientID);
  return NS_OK;
}

NS_IMETHODIMP
nsApplicationCache::Activate() {
  NS_ENSURE_TRUE(mValid, NS_ERROR_NOT_AVAILABLE);
  NS_ENSURE_TRUE(mDevice, NS_ERROR_NOT_AVAILABLE);

  mDevice->ActivateCache(mGroup, mClientID);

  if (mDevice->AutoShutdown(this)) mDevice = nullptr;

  return NS_OK;
}

NS_IMETHODIMP
nsApplicationCache::Discard() {
  NS_ENSURE_TRUE(mValid, NS_ERROR_NOT_AVAILABLE);
  NS_ENSURE_TRUE(mDevice, NS_ERROR_NOT_AVAILABLE);

  mValid = false;

  nsCOMPtr<nsIRunnable> ev =
      new nsOfflineCacheDiscardCache(mDevice, mGroup, mClientID);
  nsresult rv = nsCacheService::DispatchToCacheIOThread(ev);
  return rv;
}

NS_IMETHODIMP
nsApplicationCache::MarkEntry(const nsACString& key, uint32_t typeBits) {
  NS_ENSURE_TRUE(mValid, NS_ERROR_NOT_AVAILABLE);
  NS_ENSURE_TRUE(mDevice, NS_ERROR_NOT_AVAILABLE);

  return mDevice->MarkEntry(mClientID, key, typeBits);
}

NS_IMETHODIMP
nsApplicationCache::UnmarkEntry(const nsACString& key, uint32_t typeBits) {
  NS_ENSURE_TRUE(mValid, NS_ERROR_NOT_AVAILABLE);
  NS_ENSURE_TRUE(mDevice, NS_ERROR_NOT_AVAILABLE);

  return mDevice->UnmarkEntry(mClientID, key, typeBits);
}

NS_IMETHODIMP
nsApplicationCache::GetTypes(const nsACString& key, uint32_t* typeBits) {
  NS_ENSURE_TRUE(mValid, NS_ERROR_NOT_AVAILABLE);
  NS_ENSURE_TRUE(mDevice, NS_ERROR_NOT_AVAILABLE);

  return mDevice->GetTypes(mClientID, key, typeBits);
}

NS_IMETHODIMP
nsApplicationCache::GatherEntries(uint32_t typeBits,
                                  nsTArray<nsCString>& keys) {
  NS_ENSURE_TRUE(mValid, NS_ERROR_NOT_AVAILABLE);
  NS_ENSURE_TRUE(mDevice, NS_ERROR_NOT_AVAILABLE);

  return mDevice->GatherEntries(mClientID, typeBits, keys);
}

NS_IMETHODIMP
nsApplicationCache::AddNamespaces(nsIArray* namespaces) {
  NS_ENSURE_TRUE(mValid, NS_ERROR_NOT_AVAILABLE);
  NS_ENSURE_TRUE(mDevice, NS_ERROR_NOT_AVAILABLE);

  if (!namespaces) return NS_OK;

  mozStorageTransaction transaction(mDevice->mDB, false);

  uint32_t length;
  nsresult rv = namespaces->GetLength(&length);
  NS_ENSURE_SUCCESS(rv, rv);

  for (uint32_t i = 0; i < length; i++) {
    nsCOMPtr<nsIApplicationCacheNamespace> ns =
        do_QueryElementAt(namespaces, i);
    if (ns) {
      rv = mDevice->AddNamespace(mClientID, ns);
      NS_ENSURE_SUCCESS(rv, rv);
    }
  }

  rv = transaction.Commit();
  NS_ENSURE_SUCCESS(rv, rv);

  return NS_OK;
}

NS_IMETHODIMP
nsApplicationCache::GetMatchingNamespace(const nsACString& key,
                                         nsIApplicationCacheNamespace** out)

{
  NS_ENSURE_TRUE(mValid, NS_ERROR_NOT_AVAILABLE);
  NS_ENSURE_TRUE(mDevice, NS_ERROR_NOT_AVAILABLE);

  return mDevice->GetMatchingNamespace(mClientID, key, out);
}

NS_IMETHODIMP
nsApplicationCache::GetUsage(uint32_t* usage) {
  NS_ENSURE_TRUE(mValid, NS_ERROR_NOT_AVAILABLE);
  NS_ENSURE_TRUE(mDevice, NS_ERROR_NOT_AVAILABLE);

  return mDevice->GetUsage(mClientID, usage);
}

/******************************************************************************
 * nsCloseDBEvent
 *****************************************************************************/

class nsCloseDBEvent : public Runnable {
 public:
  explicit nsCloseDBEvent(mozIStorageConnection* aDB)
      : mozilla::Runnable("nsCloseDBEvent") {
    mDB = aDB;
  }

  NS_IMETHOD Run() override {
    mDB->Close();
    return NS_OK;
  }

 protected:
  virtual ~nsCloseDBEvent() = default;

 private:
  nsCOMPtr<mozIStorageConnection> mDB;
};

/******************************************************************************
 * nsOfflineCacheDevice
 */

NS_IMPL_ISUPPORTS0(nsOfflineCacheDevice)

nsOfflineCacheDevice::nsOfflineCacheDevice()
    : mDB(nullptr),
      mCacheCapacity(0),
      mDeltaCounter(0),
      mAutoShutdown(false),
      mLock("nsOfflineCacheDevice.lock"),
      mActiveCaches(4),
      mLockedEntries(32) {}

/* static */
bool nsOfflineCacheDevice::GetStrictFileOriginPolicy() {
  nsCOMPtr<nsIPrefBranch> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID);

  bool retval;
  if (prefs && NS_SUCCEEDED(prefs->GetBoolPref(
                   "security.fileuri.strict_origin_policy", &retval)))
    return retval;

  // As default value use true (be more strict)
  return true;
}

uint32_t nsOfflineCacheDevice::CacheSize() {
  NS_ENSURE_TRUE(Initialized(), 0);

  AutoResetStatement statement(mStatement_CacheSize);

  bool hasRows;
  nsresult rv = statement->ExecuteStep(&hasRows);
  NS_ENSURE_TRUE(NS_SUCCEEDED(rv) && hasRows, 0);

  return (uint32_t)statement->AsInt32(0);
}

uint32_t nsOfflineCacheDevice::EntryCount() {
  NS_ENSURE_TRUE(Initialized(), 0);

  AutoResetStatement statement(mStatement_EntryCount);

  bool hasRows;
  nsresult rv = statement->ExecuteStep(&hasRows);
  NS_ENSURE_TRUE(NS_SUCCEEDED(rv) && hasRows, 0);

  return (uint32_t)statement->AsInt32(0);
}

nsresult nsOfflineCacheDevice::UpdateEntry(nsCacheEntry* entry) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  // Decompose the key into "ClientID" and "Key"
  nsAutoCString keyBuf;
  const char *cid, *key;

  if (!DecomposeCacheEntryKey(entry->Key(), &cid, &key, keyBuf))
    return NS_ERROR_UNEXPECTED;

  // Store security info, if it is serializable
  nsCOMPtr<nsISupports> infoObj = entry->SecurityInfo();
  nsCOMPtr<nsISerializable> serializable = do_QueryInterface(infoObj);
  if (infoObj && !serializable) return NS_ERROR_UNEXPECTED;

  if (serializable) {
    nsCString info;
    nsresult rv = NS_SerializeToString(serializable, info);
    NS_ENSURE_SUCCESS(rv, rv);

    rv = entry->SetMetaDataElement("security-info", info.get());
    NS_ENSURE_SUCCESS(rv, rv);
  }

  nsCString metaDataBuf;
  uint32_t mdSize = entry->MetaDataSize();
  if (!metaDataBuf.SetLength(mdSize, fallible)) return NS_ERROR_OUT_OF_MEMORY;
  char* md = metaDataBuf.BeginWriting();
  entry->FlattenMetaData(md, mdSize);

  nsOfflineCacheRecord rec;
  rec.metaData = (const uint8_t*)md;
  rec.metaDataLen = mdSize;
  rec.dataSize = entry->DataSize();
  rec.fetchCount = entry->FetchCount();
  rec.lastFetched = PRTimeFromSeconds(entry->LastFetched());
  rec.lastModified = PRTimeFromSeconds(entry->LastModified());
  rec.expirationTime = PRTimeFromSeconds(entry->ExpirationTime());

  AutoResetStatement statement(mStatement_UpdateEntry);

  nsresult rv;
  rv = statement->BindBlobByIndex(0, rec.metaData, rec.metaDataLen);
  nsresult tmp = statement->BindInt32ByIndex(1, rec.dataSize);
  if (NS_FAILED(tmp)) {
    rv = tmp;
  }
  tmp = statement->BindInt32ByIndex(2, rec.fetchCount);
  if (NS_FAILED(tmp)) {
    rv = tmp;
  }
  tmp = statement->BindInt64ByIndex(3, rec.lastFetched);
  if (NS_FAILED(tmp)) {
    rv = tmp;
  }
  tmp = statement->BindInt64ByIndex(4, rec.lastModified);
  if (NS_FAILED(tmp)) {
    rv = tmp;
  }
  tmp = statement->BindInt64ByIndex(5, rec.expirationTime);
  if (NS_FAILED(tmp)) {
    rv = tmp;
  }
  tmp = statement->BindUTF8StringByIndex(6, nsDependentCString(cid));
  if (NS_FAILED(tmp)) {
    rv = tmp;
  }
  tmp = statement->BindUTF8StringByIndex(7, nsDependentCString(key));
  if (NS_FAILED(tmp)) {
    rv = tmp;
  }
  NS_ENSURE_SUCCESS(rv, rv);

  bool hasRows;
  rv = statement->ExecuteStep(&hasRows);
  NS_ENSURE_SUCCESS(rv, rv);

  NS_ASSERTION(!hasRows, "UPDATE should not result in output");
  return rv;
}

nsresult nsOfflineCacheDevice::UpdateEntrySize(nsCacheEntry* entry,
                                               uint32_t newSize) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  // Decompose the key into "ClientID" and "Key"
  nsAutoCString keyBuf;
  const char *cid, *key;
  if (!DecomposeCacheEntryKey(entry->Key(), &cid, &key, keyBuf))
    return NS_ERROR_UNEXPECTED;

  AutoResetStatement statement(mStatement_UpdateEntrySize);

  nsresult rv = statement->BindInt32ByIndex(0, newSize);
  nsresult tmp = statement->BindUTF8StringByIndex(1, nsDependentCString(cid));
  if (NS_FAILED(tmp)) {
    rv = tmp;
  }
  tmp = statement->BindUTF8StringByIndex(2, nsDependentCString(key));
  if (NS_FAILED(tmp)) {
    rv = tmp;
  }
  NS_ENSURE_SUCCESS(rv, rv);

  bool hasRows;
  rv = statement->ExecuteStep(&hasRows);
  NS_ENSURE_SUCCESS(rv, rv);

  NS_ASSERTION(!hasRows, "UPDATE should not result in output");
  return rv;
}

nsresult nsOfflineCacheDevice::DeleteEntry(nsCacheEntry* entry,
                                           bool deleteData) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  if (deleteData) {
    nsresult rv = DeleteData(entry);
    if (NS_FAILED(rv)) return rv;
  }

  // Decompose the key into "ClientID" and "Key"
  nsAutoCString keyBuf;
  const char *cid, *key;
  if (!DecomposeCacheEntryKey(entry->Key(), &cid, &key, keyBuf))
    return NS_ERROR_UNEXPECTED;

  AutoResetStatement statement(mStatement_DeleteEntry);

  nsresult rv = statement->BindUTF8StringByIndex(0, nsDependentCString(cid));
  nsresult rv2 = statement->BindUTF8StringByIndex(1, nsDependentCString(key));
  NS_ENSURE_SUCCESS(rv, rv);
  NS_ENSURE_SUCCESS(rv2, rv2);

  bool hasRows;
  rv = statement->ExecuteStep(&hasRows);
  NS_ENSURE_SUCCESS(rv, rv);

  NS_ASSERTION(!hasRows, "DELETE should not result in output");
  return rv;
}

nsresult nsOfflineCacheDevice::DeleteData(nsCacheEntry* entry) {
  nsOfflineCacheBinding* binding = (nsOfflineCacheBinding*)entry->Data();
  NS_ENSURE_STATE(binding);

  return binding->mDataFile->Remove(false);
}

/**
 * nsCacheDevice implementation
 */

// This struct is local to nsOfflineCacheDevice::Init, but ISO C++98 doesn't
// allow a template (mozilla::ArrayLength) to be instantiated based on a local
// type.  Boo-urns!
struct StatementSql {
  nsCOMPtr<mozIStorageStatement>& statement;
  const char* sql;
  StatementSql(nsCOMPtr<mozIStorageStatement>& aStatement, const char* aSql)
      : statement(aStatement), sql(aSql) {}
};

nsresult nsOfflineCacheDevice::Init() {
  MOZ_ASSERT(false, "Need to be initialized with sqlite");
  return NS_ERROR_NOT_IMPLEMENTED;
}

nsresult nsOfflineCacheDevice::InitWithSqlite(mozIStorageService* ss) {
  NS_ENSURE_TRUE(!mDB, NS_ERROR_ALREADY_INITIALIZED);

  // SetCacheParentDirectory must have been called
  NS_ENSURE_TRUE(mCacheDirectory, NS_ERROR_UNEXPECTED);

  // make sure the cache directory exists
  nsresult rv = EnsureDir(mCacheDirectory);
  NS_ENSURE_SUCCESS(rv, rv);

  // build path to index file
  nsCOMPtr<nsIFile> indexFile;
  rv = mCacheDirectory->Clone(getter_AddRefs(indexFile));
  NS_ENSURE_SUCCESS(rv, rv);
  rv = indexFile->AppendNative(NS_LITERAL_CSTRING("index.sqlite"));
  NS_ENSURE_SUCCESS(rv, rv);

  MOZ_ASSERT(ss,
             "nsOfflineCacheDevice::InitWithSqlite called before "
             "nsCacheService::Init() ?");
  NS_ENSURE_TRUE(ss, NS_ERROR_UNEXPECTED);

  rv = ss->OpenDatabase(indexFile, getter_AddRefs(mDB));
  NS_ENSURE_SUCCESS(rv, rv);

  mInitEventTarget = GetCurrentThreadEventTarget();

  mDB->ExecuteSimpleSQL(NS_LITERAL_CSTRING("PRAGMA synchronous = OFF;"));

  // XXX ... other initialization steps

  // XXX in the future we may wish to verify the schema for moz_cache
  //     perhaps using "PRAGMA table_info" ?

  // build the table
  //
  //  "Generation" is the data file generation number.
  //
  rv = mDB->ExecuteSimpleSQL(
      NS_LITERAL_CSTRING("CREATE TABLE IF NOT EXISTS moz_cache (\n"
                         "  ClientID        TEXT,\n"
                         "  Key             TEXT,\n"
                         "  MetaData        BLOB,\n"
                         "  Generation      INTEGER,\n"
                         "  DataSize        INTEGER,\n"
                         "  FetchCount      INTEGER,\n"
                         "  LastFetched     INTEGER,\n"
                         "  LastModified    INTEGER,\n"
                         "  ExpirationTime  INTEGER,\n"
                         "  ItemType        INTEGER DEFAULT 0\n"
                         ");\n"));
  NS_ENSURE_SUCCESS(rv, rv);

  // Databases from 1.9.0 don't have the ItemType column.  Add the column
  // here, but don't worry about failures (the column probably already exists)
  mDB->ExecuteSimpleSQL(NS_LITERAL_CSTRING(
      "ALTER TABLE moz_cache ADD ItemType INTEGER DEFAULT 0"));

  // Create the table for storing cache groups.  All actions on
  // moz_cache_groups use the GroupID, so use it as the primary key.
  rv = mDB->ExecuteSimpleSQL(
      NS_LITERAL_CSTRING("CREATE TABLE IF NOT EXISTS moz_cache_groups (\n"
                         " GroupID TEXT PRIMARY KEY,\n"
                         " ActiveClientID TEXT\n"
                         ");\n"));
  NS_ENSURE_SUCCESS(rv, rv);

  mDB->ExecuteSimpleSQL(
      NS_LITERAL_CSTRING("ALTER TABLE moz_cache_groups "
                         "ADD ActivateTimeStamp INTEGER DEFAULT 0"));

  // ClientID: clientID joining moz_cache and moz_cache_namespaces
  // tables.
  // Data: Data associated with this namespace (e.g. a fallback URI
  // for fallback entries).
  // ItemType: the type of namespace.
  rv =
      mDB->ExecuteSimpleSQL(NS_LITERAL_CSTRING("CREATE TABLE IF NOT EXISTS"
                                               " moz_cache_namespaces (\n"
                                               " ClientID TEXT,\n"
                                               " NameSpace TEXT,\n"
                                               " Data TEXT,\n"
                                               " ItemType INTEGER\n"
                                               ");\n"));
  NS_ENSURE_SUCCESS(rv, rv);

  // Databases from 1.9.0 have a moz_cache_index that should be dropped
  rv = mDB->ExecuteSimpleSQL(
      NS_LITERAL_CSTRING("DROP INDEX IF EXISTS moz_cache_index"));
  NS_ENSURE_SUCCESS(rv, rv);

  // Key/ClientID pairs should be unique in the database.  All queries
  // against moz_cache use the Key (which is also the most unique), so
  // use it as the primary key for this index.
  rv = mDB->ExecuteSimpleSQL(
      NS_LITERAL_CSTRING("CREATE UNIQUE INDEX IF NOT EXISTS "
                         " moz_cache_key_clientid_index"
                         " ON moz_cache (Key, ClientID);"));
  NS_ENSURE_SUCCESS(rv, rv);

  // Used for ClientID lookups and to keep ClientID/NameSpace pairs unique.
  rv = mDB->ExecuteSimpleSQL(
      NS_LITERAL_CSTRING("CREATE UNIQUE INDEX IF NOT EXISTS"
                         " moz_cache_namespaces_clientid_index"
                         " ON moz_cache_namespaces (ClientID, NameSpace);"));
  NS_ENSURE_SUCCESS(rv, rv);

  // Used for namespace lookups.
  rv = mDB->ExecuteSimpleSQL(
      NS_LITERAL_CSTRING("CREATE INDEX IF NOT EXISTS"
                         " moz_cache_namespaces_namespace_index"
                         " ON moz_cache_namespaces (NameSpace);"));
  NS_ENSURE_SUCCESS(rv, rv);

  mEvictionFunction = new nsOfflineCacheEvictionFunction(this);
  if (!mEvictionFunction) return NS_ERROR_OUT_OF_MEMORY;

  rv = mDB->CreateFunction(NS_LITERAL_CSTRING("cache_eviction_observer"), 3,
                           mEvictionFunction);
  NS_ENSURE_SUCCESS(rv, rv);

  // create all (most) of our statements up front
  StatementSql prepared[] = {
      // clang-format off
    StatementSql ( mStatement_CacheSize,         "SELECT Sum(DataSize) from moz_cache;" ),
    StatementSql ( mStatement_ApplicationCacheSize, "SELECT Sum(DataSize) from moz_cache WHERE ClientID = ?;" ),
    StatementSql ( mStatement_EntryCount,        "SELECT count(*) from moz_cache;" ),
    StatementSql ( mStatement_UpdateEntry,       "UPDATE moz_cache SET MetaData = ?, DataSize = ?, FetchCount = ?, LastFetched = ?, LastModified = ?, ExpirationTime = ? WHERE ClientID = ? AND Key = ?;" ),
    StatementSql ( mStatement_UpdateEntrySize,   "UPDATE moz_cache SET DataSize = ? WHERE ClientID = ? AND Key = ?;" ),
    StatementSql ( mStatement_DeleteEntry,       "DELETE FROM moz_cache WHERE ClientID = ? AND Key = ?;" ),
    StatementSql ( mStatement_FindEntry,         "SELECT MetaData, Generation, DataSize, FetchCount, LastFetched, LastModified, ExpirationTime, ItemType FROM moz_cache WHERE ClientID = ? AND Key = ?;" ),
    StatementSql ( mStatement_BindEntry,         "INSERT INTO moz_cache (ClientID, Key, MetaData, Generation, DataSize, FetchCount, LastFetched, LastModified, ExpirationTime) VALUES(?,?,?,?,?,?,?,?,?);" ),

    StatementSql ( mStatement_MarkEntry,         "UPDATE moz_cache SET ItemType = (ItemType | ?) WHERE ClientID = ? AND Key = ?;" ),
    StatementSql ( mStatement_UnmarkEntry,       "UPDATE moz_cache SET ItemType = (ItemType & ~?) WHERE ClientID = ? AND Key = ?;" ),
    StatementSql ( mStatement_GetTypes,          "SELECT ItemType FROM moz_cache WHERE ClientID = ? AND Key = ?;"),
    StatementSql ( mStatement_CleanupUnmarked,   "DELETE FROM moz_cache WHERE ClientID = ? AND Key = ? AND ItemType = 0;" ),
    StatementSql ( mStatement_GatherEntries,     "SELECT Key FROM moz_cache WHERE ClientID = ? AND (ItemType & ?) > 0;" ),

    StatementSql ( mStatement_ActivateClient,    "INSERT OR REPLACE INTO moz_cache_groups (GroupID, ActiveClientID, ActivateTimeStamp) VALUES (?, ?, ?);" ),
    StatementSql ( mStatement_DeactivateGroup,   "DELETE FROM moz_cache_groups WHERE GroupID = ?;" ),
    StatementSql ( mStatement_FindClient,        "/* do not warn (bug 1293375) */ SELECT ClientID, ItemType FROM moz_cache WHERE Key = ? ORDER BY LastFetched DESC, LastModified DESC;" ),

    // Search for namespaces that match the URI.  Use the <= operator
    // to ensure that we use the index on moz_cache_namespaces.
    StatementSql ( mStatement_FindClientByNamespace, "/* do not warn (bug 1293375) */ SELECT ns.ClientID, ns.ItemType FROM"
                                                     "  moz_cache_namespaces AS ns JOIN moz_cache_groups AS groups"
                                                     "  ON ns.ClientID = groups.ActiveClientID"
                                                     " WHERE ns.NameSpace <= ?1 AND ?1 GLOB ns.NameSpace || '*'"
                                                     " ORDER BY ns.NameSpace DESC, groups.ActivateTimeStamp DESC;"),
    StatementSql ( mStatement_FindNamespaceEntry,    "SELECT NameSpace, Data, ItemType FROM moz_cache_namespaces"
                                                     " WHERE ClientID = ?1"
                                                     " AND NameSpace <= ?2 AND ?2 GLOB NameSpace || '*'"
                                                     " ORDER BY NameSpace DESC;"),
    StatementSql ( mStatement_InsertNamespaceEntry,  "INSERT INTO moz_cache_namespaces (ClientID, NameSpace, Data, ItemType) VALUES(?, ?, ?, ?);"),
    StatementSql ( mStatement_EnumerateApps,         "SELECT GroupID, ActiveClientID FROM moz_cache_groups WHERE GroupID LIKE ?1;"),
    StatementSql ( mStatement_EnumerateGroups,       "SELECT GroupID, ActiveClientID FROM moz_cache_groups;"),
    StatementSql ( mStatement_EnumerateGroupsTimeOrder, "SELECT GroupID, ActiveClientID FROM moz_cache_groups ORDER BY ActivateTimeStamp;")
      // clang-format on
  };
  for (uint32_t i = 0; NS_SUCCEEDED(rv) && i < ArrayLength(prepared); ++i) {
    LOG(("Creating statement: %s\n", prepared[i].sql));

    rv = mDB->CreateStatement(nsDependentCString(prepared[i].sql),
                              getter_AddRefs(prepared[i].statement));
    NS_ENSURE_SUCCESS(rv, rv);
  }

  rv = InitActiveCaches();
  NS_ENSURE_SUCCESS(rv, rv);

  return NS_OK;
}

namespace {

nsresult GetGroupForCache(const nsACString& clientID, nsCString& group) {
  group.Assign(clientID);
  group.Truncate(group.FindChar('|'));
  NS_UnescapeURL(group);

  return NS_OK;
}

}  // namespace

// static
nsresult nsOfflineCacheDevice::BuildApplicationCacheGroupID(
    nsIURI* aManifestURL, nsACString const& aOriginSuffix,
    nsACString& _result) {
  nsCOMPtr<nsIURI> newURI;
  nsresult rv =
      NS_GetURIWithNewRef(aManifestURL, EmptyCString(), getter_AddRefs(newURI));
  NS_ENSURE_SUCCESS(rv, rv);

  nsAutoCString manifestSpec;
  rv = newURI->GetAsciiSpec(manifestSpec);
  NS_ENSURE_SUCCESS(rv, rv);

  _result.Assign(manifestSpec);
  _result.Append('#');
  _result.Append(aOriginSuffix);

  return NS_OK;
}

nsresult nsOfflineCacheDevice::InitActiveCaches() {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  MutexAutoLock lock(mLock);

  AutoResetStatement statement(mStatement_EnumerateGroups);

  bool hasRows;
  nsresult rv = statement->ExecuteStep(&hasRows);
  NS_ENSURE_SUCCESS(rv, rv);

  while (hasRows) {
    nsAutoCString group;
    statement->GetUTF8String(0, group);
    nsCString clientID;
    statement->GetUTF8String(1, clientID);

    mActiveCaches.PutEntry(clientID);
    mActiveCachesByGroup.Put(group, new nsCString(clientID));

    rv = statement->ExecuteStep(&hasRows);
    NS_ENSURE_SUCCESS(rv, rv);
  }

  return NS_OK;
}

nsresult nsOfflineCacheDevice::Shutdown() {
  NS_ENSURE_TRUE(mDB, NS_ERROR_NOT_INITIALIZED);

  {
    MutexAutoLock lock(mLock);
    for (auto iter = mCaches.Iter(); !iter.Done(); iter.Next()) {
      nsCOMPtr<nsIApplicationCache> obj = do_QueryReferent(iter.UserData());
      if (obj) {
        auto appCache = static_cast<nsApplicationCache*>(obj.get());
        appCache->MarkInvalid();
      }
    }
  }

  {
    EvictionObserver evictionObserver(mDB, mEvictionFunction);

    // Delete all rows whose clientID is not an active clientID.
    nsresult rv = mDB->ExecuteSimpleSQL(NS_LITERAL_CSTRING(
        "DELETE FROM moz_cache WHERE rowid IN"
        "  (SELECT moz_cache.rowid FROM"
        "    moz_cache LEFT OUTER JOIN moz_cache_groups ON"
        "      (moz_cache.ClientID = moz_cache_groups.ActiveClientID)"
        "   WHERE moz_cache_groups.GroupID ISNULL)"));

    if (NS_FAILED(rv))
      NS_WARNING("Failed to clean up unused application caches.");
    else
      evictionObserver.Apply();

    // Delete all namespaces whose clientID is not an active clientID.
    rv = mDB->ExecuteSimpleSQL(NS_LITERAL_CSTRING(
        "DELETE FROM moz_cache_namespaces WHERE rowid IN"
        "  (SELECT moz_cache_namespaces.rowid FROM"
        "    moz_cache_namespaces LEFT OUTER JOIN moz_cache_groups ON"
        "      (moz_cache_namespaces.ClientID = "
        "moz_cache_groups.ActiveClientID)"
        "   WHERE moz_cache_groups.GroupID ISNULL)"));

    if (NS_FAILED(rv)) NS_WARNING("Failed to clean up namespaces.");

    mEvictionFunction = nullptr;

    mStatement_CacheSize = nullptr;
    mStatement_ApplicationCacheSize = nullptr;
    mStatement_EntryCount = nullptr;
    mStatement_UpdateEntry = nullptr;
    mStatement_UpdateEntrySize = nullptr;
    mStatement_DeleteEntry = nullptr;
    mStatement_FindEntry = nullptr;
    mStatement_BindEntry = nullptr;
    mStatement_ClearDomain = nullptr;
    mStatement_MarkEntry = nullptr;
    mStatement_UnmarkEntry = nullptr;
    mStatement_GetTypes = nullptr;
    mStatement_FindNamespaceEntry = nullptr;
    mStatement_InsertNamespaceEntry = nullptr;
    mStatement_CleanupUnmarked = nullptr;
    mStatement_GatherEntries = nullptr;
    mStatement_ActivateClient = nullptr;
    mStatement_DeactivateGroup = nullptr;
    mStatement_FindClient = nullptr;
    mStatement_FindClientByNamespace = nullptr;
    mStatement_EnumerateApps = nullptr;
    mStatement_EnumerateGroups = nullptr;
    mStatement_EnumerateGroupsTimeOrder = nullptr;
  }

  // Close Database on the correct thread
  bool isOnCurrentThread = true;
  if (mInitEventTarget)
    isOnCurrentThread = mInitEventTarget->IsOnCurrentThread();

  if (!isOnCurrentThread) {
    nsCOMPtr<nsIRunnable> ev = new nsCloseDBEvent(mDB);

    if (ev) {
      mInitEventTarget->Dispatch(ev, NS_DISPATCH_NORMAL);
    }
  } else {
    mDB->Close();
  }

  mDB = nullptr;
  mInitEventTarget = nullptr;

  return NS_OK;
}

const char* nsOfflineCacheDevice::GetDeviceID() {
  return OFFLINE_CACHE_DEVICE_ID;
}

nsCacheEntry* nsOfflineCacheDevice::FindEntry(nsCString* fullKey,
                                              bool* collision) {
  NS_ENSURE_TRUE(Initialized(), nullptr);

  mozilla::Telemetry::AutoTimer<mozilla::Telemetry::CACHE_OFFLINE_SEARCH_2>
      timer;
  LOG(("nsOfflineCacheDevice::FindEntry [key=%s]\n", fullKey->get()));

  // SELECT * FROM moz_cache WHERE key = ?

  // Decompose the key into "ClientID" and "Key"
  nsAutoCString keyBuf;
  const char *cid, *key;
  if (!DecomposeCacheEntryKey(fullKey, &cid, &key, keyBuf)) return nullptr;

  AutoResetStatement statement(mStatement_FindEntry);

  nsresult rv = statement->BindUTF8StringByIndex(0, nsDependentCString(cid));
  nsresult rv2 = statement->BindUTF8StringByIndex(1, nsDependentCString(key));
  NS_ENSURE_SUCCESS(rv, nullptr);
  NS_ENSURE_SUCCESS(rv2, nullptr);

  bool hasRows;
  rv = statement->ExecuteStep(&hasRows);
  if (NS_FAILED(rv) || !hasRows) return nullptr;  // entry not found

  nsOfflineCacheRecord rec;
  statement->GetSharedBlob(0, &rec.metaDataLen, (const uint8_t**)&rec.metaData);
  rec.generation = statement->AsInt32(1);
  rec.dataSize = statement->AsInt32(2);
  rec.fetchCount = statement->AsInt32(3);
  rec.lastFetched = statement->AsInt64(4);
  rec.lastModified = statement->AsInt64(5);
  rec.expirationTime = statement->AsInt64(6);

  LOG(("entry: [%u %d %d %d %" PRId64 " %" PRId64 " %" PRId64 "]\n",
       rec.metaDataLen, rec.generation, rec.dataSize, rec.fetchCount,
       rec.lastFetched, rec.lastModified, rec.expirationTime));

  nsCacheEntry* entry = CreateCacheEntry(this, fullKey, rec);

  if (entry) {
    // make sure that the data file exists
    nsOfflineCacheBinding* binding = (nsOfflineCacheBinding*)entry->Data();
    bool isFile;
    rv = binding->mDataFile->IsFile(&isFile);
    if (NS_FAILED(rv) || !isFile) {
      DeleteEntry(entry, false);
      delete entry;
      return nullptr;
    }

    // lock the entry
    Lock(*fullKey);
  }

  return entry;
}

nsresult nsOfflineCacheDevice::DeactivateEntry(nsCacheEntry* entry) {
  LOG(("nsOfflineCacheDevice::DeactivateEntry [key=%s]\n",
       entry->Key()->get()));

  // This method is called to inform us that the nsCacheEntry object is going
  // away.  We should persist anything that needs to be persisted, or if the
  // entry is doomed, we can go ahead and clear its storage.

  if (entry->IsDoomed()) {
    // remove corresponding row and file if they exist

    // the row should have been removed in DoomEntry... we could assert that
    // that happened.  otherwise, all we have to do here is delete the file
    // on disk.
    DeleteData(entry);
  } else if (((nsOfflineCacheBinding*)entry->Data())->IsNewEntry()) {
    // UPDATE the database row

    // Only new entries are updated, since offline cache is updated in
    // transactions.  New entries are those who is returned from
    // BindEntry().

    LOG(("nsOfflineCacheDevice::DeactivateEntry updating new entry\n"));
    UpdateEntry(entry);
  } else {
    LOG(
        ("nsOfflineCacheDevice::DeactivateEntry "
         "skipping update since entry is not dirty\n"));
  }

  // Unlock the entry
  Unlock(*entry->Key());

  delete entry;

  return NS_OK;
}

nsresult nsOfflineCacheDevice::BindEntry(nsCacheEntry* entry) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  LOG(("nsOfflineCacheDevice::BindEntry [key=%s]\n", entry->Key()->get()));

  NS_ENSURE_STATE(!entry->Data());

  // This method is called to inform us that we have a new entry.  The entry
  // may collide with an existing entry in our DB, but if that happens we can
  // assume that the entry is not being used.

  // INSERT the database row

  // XXX Assumption: if the row already exists, then FindEntry would have
  // returned it.  if that entry was doomed, then DoomEntry would have removed
  // it from the table.  so, we should always have to insert at this point.

  // Decompose the key into "ClientID" and "Key"
  nsAutoCString keyBuf;
  const char *cid, *key;
  if (!DecomposeCacheEntryKey(entry->Key(), &cid, &key, keyBuf))
    return NS_ERROR_UNEXPECTED;

  // create binding, pick best generation number
  RefPtr<nsOfflineCacheBinding> binding =
      nsOfflineCacheBinding::Create(mCacheDirectory, entry->Key(), -1);
  if (!binding) return NS_ERROR_OUT_OF_MEMORY;
  binding->MarkNewEntry();

  nsOfflineCacheRecord rec;
  rec.clientID = cid;
  rec.key = key;
  rec.metaData = nullptr;  // don't write any metadata now.
  rec.metaDataLen = 0;
  rec.generation = binding->mGeneration;
  rec.dataSize = 0;
  rec.fetchCount = entry->FetchCount();
  rec.lastFetched = PRTimeFromSeconds(entry->LastFetched());
  rec.lastModified = PRTimeFromSeconds(entry->LastModified());
  rec.expirationTime = PRTimeFromSeconds(entry->ExpirationTime());

  AutoResetStatement statement(mStatement_BindEntry);

  nsresult rv =
      statement->BindUTF8StringByIndex(0, nsDependentCString(rec.clientID));
  nsresult tmp =
      statement->BindUTF8StringByIndex(1, nsDependentCString(rec.key));
  if (NS_FAILED(tmp)) {
    rv = tmp;
  }
  tmp = statement->BindBlobByIndex(2, rec.metaData, rec.metaDataLen);
  if (NS_FAILED(tmp)) {
    rv = tmp;
  }
  tmp = statement->BindInt32ByIndex(3, rec.generation);
  if (NS_FAILED(tmp)) {
    rv = tmp;
  }
  tmp = statement->BindInt32ByIndex(4, rec.dataSize);
  if (NS_FAILED(tmp)) {
    rv = tmp;
  }
  tmp = statement->BindInt32ByIndex(5, rec.fetchCount);
  if (NS_FAILED(tmp)) {
    rv = tmp;
  }
  tmp = statement->BindInt64ByIndex(6, rec.lastFetched);
  if (NS_FAILED(tmp)) {
    rv = tmp;
  }
  tmp = statement->BindInt64ByIndex(7, rec.lastModified);
  if (NS_FAILED(tmp)) {
    rv = tmp;
  }
  tmp = statement->BindInt64ByIndex(8, rec.expirationTime);
  if (NS_FAILED(tmp)) {
    rv = tmp;
  }
  NS_ENSURE_SUCCESS(rv, rv);

  bool hasRows;
  rv = statement->ExecuteStep(&hasRows);
  NS_ENSURE_SUCCESS(rv, rv);
  NS_ASSERTION(!hasRows, "INSERT should not result in output");

  entry->SetData(binding);

  // lock the entry
  Lock(*entry->Key());

  return NS_OK;
}

void nsOfflineCacheDevice::DoomEntry(nsCacheEntry* entry) {
  LOG(("nsOfflineCacheDevice::DoomEntry [key=%s]\n", entry->Key()->get()));

  // This method is called to inform us that we should mark the entry to be
  // deleted when it is no longer in use.

  // We can go ahead and delete the corresponding row in our table,
  // but we must not delete the file on disk until we are deactivated.
  // In another word, the file should be deleted if the entry had been
  // deactivated.

  DeleteEntry(entry, !entry->IsActive());
}

nsresult nsOfflineCacheDevice::OpenInputStreamForEntry(
    nsCacheEntry* entry, nsCacheAccessMode mode, uint32_t offset,
    nsIInputStream** result) {
  LOG(("nsOfflineCacheDevice::OpenInputStreamForEntry [key=%s]\n",
       entry->Key()->get()));

  *result = nullptr;

  NS_ENSURE_TRUE(!offset || (offset < entry->DataSize()), NS_ERROR_INVALID_ARG);

  // return an input stream to the entry's data file.  the stream
  // may be read on a background thread.

  nsOfflineCacheBinding* binding = (nsOfflineCacheBinding*)entry->Data();
  NS_ENSURE_STATE(binding);

  nsCOMPtr<nsIInputStream> in;
  NS_NewLocalFileInputStream(getter_AddRefs(in), binding->mDataFile, PR_RDONLY);
  if (!in) return NS_ERROR_UNEXPECTED;

  // respect |offset| param
  if (offset != 0) {
    nsCOMPtr<nsISeekableStream> seekable = do_QueryInterface(in);
    NS_ENSURE_TRUE(seekable, NS_ERROR_UNEXPECTED);

    seekable->Seek(nsISeekableStream::NS_SEEK_SET, offset);
  }

  in.swap(*result);
  return NS_OK;
}

nsresult nsOfflineCacheDevice::OpenOutputStreamForEntry(
    nsCacheEntry* entry, nsCacheAccessMode mode, uint32_t offset,
    nsIOutputStream** result) {
  LOG(("nsOfflineCacheDevice::OpenOutputStreamForEntry [key=%s]\n",
       entry->Key()->get()));

  *result = nullptr;

  NS_ENSURE_TRUE(offset <= entry->DataSize(), NS_ERROR_INVALID_ARG);

  // return an output stream to the entry's data file.  we can assume
  // that the output stream will only be used on the main thread.

  nsOfflineCacheBinding* binding = (nsOfflineCacheBinding*)entry->Data();
  NS_ENSURE_STATE(binding);

  nsCOMPtr<nsIOutputStream> out;
  NS_NewLocalFileOutputStream(getter_AddRefs(out), binding->mDataFile,
                              PR_WRONLY | PR_CREATE_FILE | PR_TRUNCATE, 00600);
  if (!out) return NS_ERROR_UNEXPECTED;

  // respect |offset| param
  nsCOMPtr<nsISeekableStream> seekable = do_QueryInterface(out);
  NS_ENSURE_TRUE(seekable, NS_ERROR_UNEXPECTED);
  if (offset != 0) seekable->Seek(nsISeekableStream::NS_SEEK_SET, offset);

  // truncate the file at the given offset
  seekable->SetEOF();

  nsCOMPtr<nsIOutputStream> bufferedOut;
  nsresult rv = NS_NewBufferedOutputStream(getter_AddRefs(bufferedOut),
                                           out.forget(), 16 * 1024);
  NS_ENSURE_SUCCESS(rv, rv);

  bufferedOut.forget(result);
  return NS_OK;
}

nsresult nsOfflineCacheDevice::GetFileForEntry(nsCacheEntry* entry,
                                               nsIFile** result) {
  LOG(("nsOfflineCacheDevice::GetFileForEntry [key=%s]\n",
       entry->Key()->get()));

  nsOfflineCacheBinding* binding = (nsOfflineCacheBinding*)entry->Data();
  NS_ENSURE_STATE(binding);

  NS_IF_ADDREF(*result = binding->mDataFile);
  return NS_OK;
}

nsresult nsOfflineCacheDevice::OnDataSizeChange(nsCacheEntry* entry,
                                                int32_t deltaSize) {
  LOG(("nsOfflineCacheDevice::OnDataSizeChange [key=%s delta=%d]\n",
       entry->Key()->get(), deltaSize));

  const int32_t DELTA_THRESHOLD = 1 << 14;  // 16k

  // called to notify us of an impending change in the total size of the
  // specified entry.

  uint32_t oldSize = entry->DataSize();
  NS_ASSERTION(deltaSize >= 0 || int32_t(oldSize) + deltaSize >= 0, "oops");
  uint32_t newSize = int32_t(oldSize) + deltaSize;
  UpdateEntrySize(entry, newSize);

  mDeltaCounter += deltaSize;  // this may go negative

  if (mDeltaCounter >= DELTA_THRESHOLD) {
    if (CacheSize() > mCacheCapacity) {
      // the entry will overrun the cache capacity, doom the entry
      // and abort
#ifdef DEBUG
      nsresult rv =
#endif
          nsCacheService::DoomEntry(entry);
      NS_ASSERTION(NS_SUCCEEDED(rv), "DoomEntry() failed.");
      return NS_ERROR_ABORT;
    }

    mDeltaCounter = 0;  // reset counter
  }

  return NS_OK;
}

nsresult nsOfflineCacheDevice::Visit(nsICacheVisitor* visitor) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  // called to enumerate the offline cache.

  nsCOMPtr<nsICacheDeviceInfo> deviceInfo = new nsOfflineCacheDeviceInfo(this);

  bool keepGoing;
  nsresult rv =
      visitor->VisitDevice(OFFLINE_CACHE_DEVICE_ID, deviceInfo, &keepGoing);
  if (NS_FAILED(rv)) return rv;

  if (!keepGoing) return NS_OK;

  // SELECT * from moz_cache;

  nsOfflineCacheRecord rec;
  RefPtr<nsOfflineCacheEntryInfo> info = new nsOfflineCacheEntryInfo;
  if (!info) return NS_ERROR_OUT_OF_MEMORY;
  info->mRec = &rec;

  // XXX may want to list columns explicitly
  nsCOMPtr<mozIStorageStatement> statement;
  rv = mDB->CreateStatement(NS_LITERAL_CSTRING("SELECT * FROM moz_cache;"),
                            getter_AddRefs(statement));
  NS_ENSURE_SUCCESS(rv, rv);

  bool hasRows;
  for (;;) {
    rv = statement->ExecuteStep(&hasRows);
    if (NS_FAILED(rv) || !hasRows) break;

    statement->GetSharedUTF8String(0, nullptr, &rec.clientID);
    statement->GetSharedUTF8String(1, nullptr, &rec.key);
    statement->GetSharedBlob(2, &rec.metaDataLen,
                             (const uint8_t**)&rec.metaData);
    rec.generation = statement->AsInt32(3);
    rec.dataSize = statement->AsInt32(4);
    rec.fetchCount = statement->AsInt32(5);
    rec.lastFetched = statement->AsInt64(6);
    rec.lastModified = statement->AsInt64(7);
    rec.expirationTime = statement->AsInt64(8);

    bool keepGoing;
    rv = visitor->VisitEntry(OFFLINE_CACHE_DEVICE_ID, info, &keepGoing);
    if (NS_FAILED(rv) || !keepGoing) break;
  }

  info->mRec = nullptr;
  return NS_OK;
}

nsresult nsOfflineCacheDevice::EvictEntries(const char* clientID) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  LOG(("nsOfflineCacheDevice::EvictEntries [cid=%s]\n",
       clientID ? clientID : ""));

  // called to evict all entries matching the given clientID.

  // need trigger to fire user defined function after a row is deleted
  // so we can delete the corresponding data file.
  EvictionObserver evictionObserver(mDB, mEvictionFunction);

  nsCOMPtr<mozIStorageStatement> statement;
  nsresult rv;
  if (clientID) {
    rv = mDB->CreateStatement(
        NS_LITERAL_CSTRING("DELETE FROM moz_cache WHERE ClientID=?;"),
        getter_AddRefs(statement));
    NS_ENSURE_SUCCESS(rv, rv);

    rv = statement->BindUTF8StringByIndex(0, nsDependentCString(clientID));
    NS_ENSURE_SUCCESS(rv, rv);

    rv = statement->Execute();
    NS_ENSURE_SUCCESS(rv, rv);

    rv = mDB->CreateStatement(
        NS_LITERAL_CSTRING(
            "DELETE FROM moz_cache_groups WHERE ActiveClientID=?;"),
        getter_AddRefs(statement));
    NS_ENSURE_SUCCESS(rv, rv);

    rv = statement->BindUTF8StringByIndex(0, nsDependentCString(clientID));
    NS_ENSURE_SUCCESS(rv, rv);

    rv = statement->Execute();
    NS_ENSURE_SUCCESS(rv, rv);

    // TODO - Should update internal hashtables.
    // Low priority, since this API is not widely used.
  } else {
    rv = mDB->CreateStatement(NS_LITERAL_CSTRING("DELETE FROM moz_cache;"),
                              getter_AddRefs(statement));
    NS_ENSURE_SUCCESS(rv, rv);

    rv = statement->Execute();
    NS_ENSURE_SUCCESS(rv, rv);

    rv = mDB->CreateStatement(
        NS_LITERAL_CSTRING("DELETE FROM moz_cache_groups;"),
        getter_AddRefs(statement));
    NS_ENSURE_SUCCESS(rv, rv);

    rv = statement->Execute();
    NS_ENSURE_SUCCESS(rv, rv);

    MutexAutoLock lock(mLock);
    mCaches.Clear();
    mActiveCaches.Clear();
    mActiveCachesByGroup.Clear();
  }

  evictionObserver.Apply();

  statement = nullptr;
  // Also evict any namespaces associated with this clientID.
  if (clientID) {
    rv = mDB->CreateStatement(
        NS_LITERAL_CSTRING("DELETE FROM moz_cache_namespaces WHERE ClientID=?"),
        getter_AddRefs(statement));
    NS_ENSURE_SUCCESS(rv, rv);

    rv = statement->BindUTF8StringByIndex(0, nsDependentCString(clientID));
    NS_ENSURE_SUCCESS(rv, rv);
  } else {
    rv = mDB->CreateStatement(
        NS_LITERAL_CSTRING("DELETE FROM moz_cache_namespaces;"),
        getter_AddRefs(statement));
    NS_ENSURE_SUCCESS(rv, rv);
  }

  rv = statement->Execute();
  NS_ENSURE_SUCCESS(rv, rv);

  return NS_OK;
}

nsresult nsOfflineCacheDevice::MarkEntry(const nsCString& clientID,
                                         const nsACString& key,
                                         uint32_t typeBits) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  LOG(("nsOfflineCacheDevice::MarkEntry [cid=%s, key=%s, typeBits=%d]\n",
       clientID.get(), PromiseFlatCString(key).get(), typeBits));

  AutoResetStatement statement(mStatement_MarkEntry);
  nsresult rv = statement->BindInt32ByIndex(0, typeBits);
  NS_ENSURE_SUCCESS(rv, rv);
  rv = statement->BindUTF8StringByIndex(1, clientID);
  NS_ENSURE_SUCCESS(rv, rv);
  rv = statement->BindUTF8StringByIndex(2, key);
  NS_ENSURE_SUCCESS(rv, rv);

  rv = statement->Execute();
  NS_ENSURE_SUCCESS(rv, rv);

  return NS_OK;
}

nsresult nsOfflineCacheDevice::UnmarkEntry(const nsCString& clientID,
                                           const nsACString& key,
                                           uint32_t typeBits) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  LOG(("nsOfflineCacheDevice::UnmarkEntry [cid=%s, key=%s, typeBits=%d]\n",
       clientID.get(), PromiseFlatCString(key).get(), typeBits));

  AutoResetStatement statement(mStatement_UnmarkEntry);
  nsresult rv = statement->BindInt32ByIndex(0, typeBits);
  NS_ENSURE_SUCCESS(rv, rv);
  rv = statement->BindUTF8StringByIndex(1, clientID);
  NS_ENSURE_SUCCESS(rv, rv);
  rv = statement->BindUTF8StringByIndex(2, key);
  NS_ENSURE_SUCCESS(rv, rv);

  rv = statement->Execute();
  NS_ENSURE_SUCCESS(rv, rv);

  // Remove the entry if it is now empty.

  EvictionObserver evictionObserver(mDB, mEvictionFunction);

  AutoResetStatement cleanupStatement(mStatement_CleanupUnmarked);
  rv = cleanupStatement->BindUTF8StringByIndex(0, clientID);
  NS_ENSURE_SUCCESS(rv, rv);
  rv = cleanupStatement->BindUTF8StringByIndex(1, key);
  NS_ENSURE_SUCCESS(rv, rv);

  rv = cleanupStatement->Execute();
  NS_ENSURE_SUCCESS(rv, rv);

  evictionObserver.Apply();

  return NS_OK;
}

nsresult nsOfflineCacheDevice::GetMatchingNamespace(
    const nsCString& clientID, const nsACString& key,
    nsIApplicationCacheNamespace** out) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  LOG(("nsOfflineCacheDevice::GetMatchingNamespace [cid=%s, key=%s]\n",
       clientID.get(), PromiseFlatCString(key).get()));

  nsresult rv;

  AutoResetStatement statement(mStatement_FindNamespaceEntry);

  rv = statement->BindUTF8StringByIndex(0, clientID);
  NS_ENSURE_SUCCESS(rv, rv);
  rv = statement->BindUTF8StringByIndex(1, key);
  NS_ENSURE_SUCCESS(rv, rv);

  bool hasRows;
  rv = statement->ExecuteStep(&hasRows);
  NS_ENSURE_SUCCESS(rv, rv);

  *out = nullptr;

  bool found = false;
  nsCString nsSpec;
  int32_t nsType = 0;
  nsCString nsData;

  while (hasRows) {
    int32_t itemType;
    rv = statement->GetInt32(2, &itemType);
    NS_ENSURE_SUCCESS(rv, rv);

    if (!found || itemType > nsType) {
      nsType = itemType;

      rv = statement->GetUTF8String(0, nsSpec);
      NS_ENSURE_SUCCESS(rv, rv);

      rv = statement->GetUTF8String(1, nsData);
      NS_ENSURE_SUCCESS(rv, rv);

      found = true;
    }

    rv = statement->ExecuteStep(&hasRows);
    NS_ENSURE_SUCCESS(rv, rv);
  }

  if (found) {
    nsCOMPtr<nsIApplicationCacheNamespace> ns =
        new nsApplicationCacheNamespace();
    if (!ns) return NS_ERROR_OUT_OF_MEMORY;
    rv = ns->Init(nsType, nsSpec, nsData);
    NS_ENSURE_SUCCESS(rv, rv);

    ns.swap(*out);
  }

  return NS_OK;
}

nsresult nsOfflineCacheDevice::CacheOpportunistically(const nsCString& clientID,
                                                      const nsACString& key) {
  // XXX: We should also be propagating this cache entry to other matching
  // caches.  See bug 444807.

  return MarkEntry(clientID, key, nsIApplicationCache::ITEM_OPPORTUNISTIC);
}

nsresult nsOfflineCacheDevice::GetTypes(const nsCString& clientID,
                                        const nsACString& key,
                                        uint32_t* typeBits) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  LOG(("nsOfflineCacheDevice::GetTypes [cid=%s, key=%s]\n", clientID.get(),
       PromiseFlatCString(key).get()));

  AutoResetStatement statement(mStatement_GetTypes);
  nsresult rv = statement->BindUTF8StringByIndex(0, clientID);
  NS_ENSURE_SUCCESS(rv, rv);
  rv = statement->BindUTF8StringByIndex(1, key);
  NS_ENSURE_SUCCESS(rv, rv);

  bool hasRows;
  rv = statement->ExecuteStep(&hasRows);
  NS_ENSURE_SUCCESS(rv, rv);

  if (!hasRows) return NS_ERROR_CACHE_KEY_NOT_FOUND;

  *typeBits = statement->AsInt32(0);

  return NS_OK;
}

nsresult nsOfflineCacheDevice::GatherEntries(const nsCString& clientID,
                                             uint32_t typeBits,
                                             nsTArray<nsCString>& keys) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  LOG(("nsOfflineCacheDevice::GatherEntries [cid=%s, typeBits=%X]\n",
       clientID.get(), typeBits));

  AutoResetStatement statement(mStatement_GatherEntries);
  nsresult rv = statement->BindUTF8StringByIndex(0, clientID);
  NS_ENSURE_SUCCESS(rv, rv);

  rv = statement->BindInt32ByIndex(1, typeBits);
  NS_ENSURE_SUCCESS(rv, rv);

  return RunSimpleQuery(mStatement_GatherEntries, 0, keys);
}

nsresult nsOfflineCacheDevice::AddNamespace(const nsCString& clientID,
                                            nsIApplicationCacheNamespace* ns) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  nsCString namespaceSpec;
  nsresult rv = ns->GetNamespaceSpec(namespaceSpec);
  NS_ENSURE_SUCCESS(rv, rv);

  nsCString data;
  rv = ns->GetData(data);
  NS_ENSURE_SUCCESS(rv, rv);

  uint32_t itemType;
  rv = ns->GetItemType(&itemType);
  NS_ENSURE_SUCCESS(rv, rv);

  LOG(("nsOfflineCacheDevice::AddNamespace [cid=%s, ns=%s, data=%s, type=%d]",
       clientID.get(), namespaceSpec.get(), data.get(), itemType));

  AutoResetStatement statement(mStatement_InsertNamespaceEntry);

  rv = statement->BindUTF8StringByIndex(0, clientID);
  NS_ENSURE_SUCCESS(rv, rv);

  rv = statement->BindUTF8StringByIndex(1, namespaceSpec);
  NS_ENSURE_SUCCESS(rv, rv);

  rv = statement->BindUTF8StringByIndex(2, data);
  NS_ENSURE_SUCCESS(rv, rv);

  rv = statement->BindInt32ByIndex(3, itemType);
  NS_ENSURE_SUCCESS(rv, rv);

  rv = statement->Execute();
  NS_ENSURE_SUCCESS(rv, rv);

  return NS_OK;
}

nsresult nsOfflineCacheDevice::GetUsage(const nsACString& clientID,
                                        uint32_t* usage) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  LOG(("nsOfflineCacheDevice::GetUsage [cid=%s]\n",
       PromiseFlatCString(clientID).get()));

  *usage = 0;

  AutoResetStatement statement(mStatement_ApplicationCacheSize);

  nsresult rv = statement->BindUTF8StringByIndex(0, clientID);
  NS_ENSURE_SUCCESS(rv, rv);

  bool hasRows;
  rv = statement->ExecuteStep(&hasRows);
  NS_ENSURE_SUCCESS(rv, rv);

  if (!hasRows) return NS_OK;

  *usage = static_cast<uint32_t>(statement->AsInt32(0));

  return NS_OK;
}

nsresult nsOfflineCacheDevice::GetGroups(nsTArray<nsCString>& keys) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  LOG(("nsOfflineCacheDevice::GetGroups"));

  return RunSimpleQuery(mStatement_EnumerateGroups, 0, keys);
}

nsresult nsOfflineCacheDevice::GetGroupsTimeOrdered(nsTArray<nsCString>& keys) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  LOG(("nsOfflineCacheDevice::GetGroupsTimeOrder"));

  return RunSimpleQuery(mStatement_EnumerateGroupsTimeOrder, 0, keys);
}

bool nsOfflineCacheDevice::IsLocked(const nsACString& key) {
  MutexAutoLock lock(mLock);
  return mLockedEntries.GetEntry(key);
}

void nsOfflineCacheDevice::Lock(const nsACString& key) {
  MutexAutoLock lock(mLock);
  mLockedEntries.PutEntry(key);
}

void nsOfflineCacheDevice::Unlock(const nsACString& key) {
  MutexAutoLock lock(mLock);
  mLockedEntries.RemoveEntry(key);
}

nsresult nsOfflineCacheDevice::RunSimpleQuery(mozIStorageStatement* statement,
                                              uint32_t resultIndex,
                                              nsTArray<nsCString>& values) {
  bool hasRows;
  nsresult rv = statement->ExecuteStep(&hasRows);
  NS_ENSURE_SUCCESS(rv, rv);

  nsTArray<nsCString> valArray;
  while (hasRows) {
    uint32_t length;
    valArray.AppendElement(nsDependentCString(
        statement->AsSharedUTF8String(resultIndex, &length)));

    rv = statement->ExecuteStep(&hasRows);
    NS_ENSURE_SUCCESS(rv, rv);
  }

  values.SwapElements(valArray);
  return NS_OK;
}

nsresult nsOfflineCacheDevice::CreateApplicationCache(
    const nsACString& group, nsIApplicationCache** out) {
  *out = nullptr;

  nsCString clientID;
  // Some characters are special in the clientID.  Escape the groupID
  // before putting it in to the client key.
  if (!NS_Escape(nsCString(group), clientID, url_Path)) {
    return NS_ERROR_OUT_OF_MEMORY;
  }

  PRTime now = PR_Now();

  // Include the timestamp to guarantee uniqueness across runs, and
  // the gNextTemporaryClientID for uniqueness within a second.
  clientID.Append(nsPrintfCString("|%016" PRId64 "|%d", now / PR_USEC_PER_SEC,
                                  gNextTemporaryClientID++));

  nsCOMPtr<nsIApplicationCache> cache =
      new nsApplicationCache(this, group, clientID);
  if (!cache) return NS_ERROR_OUT_OF_MEMORY;

  nsWeakPtr weak = do_GetWeakReference(cache);
  if (!weak) return NS_ERROR_OUT_OF_MEMORY;

  MutexAutoLock lock(mLock);
  mCaches.Put(clientID, weak);

  cache.swap(*out);

  return NS_OK;
}

nsresult nsOfflineCacheDevice::GetApplicationCache(const nsACString& clientID,
                                                   nsIApplicationCache** out) {
  MutexAutoLock lock(mLock);
  return GetApplicationCache_Unlocked(clientID, out);
}

nsresult nsOfflineCacheDevice::GetApplicationCache_Unlocked(
    const nsACString& clientID, nsIApplicationCache** out) {
  *out = nullptr;

  nsCOMPtr<nsIApplicationCache> cache;

  nsWeakPtr weak;
  if (mCaches.Get(clientID, getter_AddRefs(weak)))
    cache = do_QueryReferent(weak);

  if (!cache) {
    nsCString group;
    nsresult rv = GetGroupForCache(clientID, group);
    NS_ENSURE_SUCCESS(rv, rv);

    if (group.IsEmpty()) {
      return NS_OK;
    }

    cache = new nsApplicationCache(this, group, clientID);
    weak = do_GetWeakReference(cache);
    if (!weak) return NS_ERROR_OUT_OF_MEMORY;

    mCaches.Put(clientID, weak);
  }

  cache.swap(*out);

  return NS_OK;
}

nsresult nsOfflineCacheDevice::GetActiveCache(const nsACString& group,
                                              nsIApplicationCache** out) {
  *out = nullptr;

  MutexAutoLock lock(mLock);

  nsCString* clientID;
  if (mActiveCachesByGroup.Get(group, &clientID))
    return GetApplicationCache_Unlocked(*clientID, out);

  return NS_OK;
}

nsresult nsOfflineCacheDevice::DeactivateGroup(const nsACString& group) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  nsCString* active = nullptr;

  AutoResetStatement statement(mStatement_DeactivateGroup);
  nsresult rv = statement->BindUTF8StringByIndex(0, group);
  NS_ENSURE_SUCCESS(rv, rv);

  rv = statement->Execute();
  NS_ENSURE_SUCCESS(rv, rv);

  MutexAutoLock lock(mLock);

  if (mActiveCachesByGroup.Get(group, &active)) {
    mActiveCaches.RemoveEntry(*active);
    mActiveCachesByGroup.Remove(group);
    active = nullptr;
  }

  return NS_OK;
}

nsresult nsOfflineCacheDevice::Evict(nsILoadContextInfo* aInfo) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  NS_ENSURE_ARG(aInfo);

  nsresult rv;

  mozilla::OriginAttributes const* oa = aInfo->OriginAttributesPtr();

  if (oa->mInIsolatedMozBrowser == false) {
    nsCOMPtr<nsICacheService> serv = do_GetService(kCacheServiceCID, &rv);
    NS_ENSURE_SUCCESS(rv, rv);

    return nsCacheService::GlobalInstance()->EvictEntriesInternal(
        nsICache::STORE_OFFLINE);
  }

  nsAutoCString jaridsuffix;
  jaridsuffix.Append('%');

  nsAutoCString suffix;
  oa->CreateSuffix(suffix);
  jaridsuffix.Append('#');
  jaridsuffix.Append(suffix);

  AutoResetStatement statement(mStatement_EnumerateApps);
  rv = statement->BindUTF8StringByIndex(0, jaridsuffix);
  NS_ENSURE_SUCCESS(rv, rv);

  bool hasRows;
  rv = statement->ExecuteStep(&hasRows);
  NS_ENSURE_SUCCESS(rv, rv);

  while (hasRows) {
    nsAutoCString group;
    rv = statement->GetUTF8String(0, group);
    NS_ENSURE_SUCCESS(rv, rv);

    nsCString clientID;
    rv = statement->GetUTF8String(1, clientID);
    NS_ENSURE_SUCCESS(rv, rv);

    nsCOMPtr<nsIRunnable> ev =
        new nsOfflineCacheDiscardCache(this, group, clientID);

    rv = nsCacheService::DispatchToCacheIOThread(ev);
    NS_ENSURE_SUCCESS(rv, rv);

    rv = statement->ExecuteStep(&hasRows);
    NS_ENSURE_SUCCESS(rv, rv);
  }

  return NS_OK;
}

namespace {  // anon

class OriginMatch final : public mozIStorageFunction {
  ~OriginMatch() = default;
  mozilla::OriginAttributesPattern const mPattern;

  NS_DECL_ISUPPORTS
  NS_DECL_MOZISTORAGEFUNCTION
  explicit OriginMatch(mozilla::OriginAttributesPattern const& aPattern)
      : mPattern(aPattern) {}
};

NS_IMPL_ISUPPORTS(OriginMatch, mozIStorageFunction)

NS_IMETHODIMP
OriginMatch::OnFunctionCall(mozIStorageValueArray* aFunctionArguments,
                            nsIVariant** aResult) {
  nsresult rv;

  nsAutoCString groupId;
  rv = aFunctionArguments->GetUTF8String(0, groupId);
  NS_ENSURE_SUCCESS(rv, rv);

  int32_t hash = groupId.Find(NS_LITERAL_CSTRING("#"));
  if (hash == kNotFound) {
    // Just ignore...
    return NS_OK;
  }

  ++hash;

  nsDependentCSubstring suffix(groupId.BeginReading() + hash,
                               groupId.Length() - hash);

  mozilla::OriginAttributes oa;
  bool ok = oa.PopulateFromSuffix(suffix);
  NS_ENSURE_TRUE(ok, NS_ERROR_UNEXPECTED);

  bool match = mPattern.Matches(oa);

  RefPtr<nsVariant> outVar(new nsVariant());
  rv = outVar->SetAsUint32(match ? 1 : 0);
  NS_ENSURE_SUCCESS(rv, rv);

  outVar.forget(aResult);
  return NS_OK;
}

}  // namespace

nsresult nsOfflineCacheDevice::Evict(
    mozilla::OriginAttributesPattern const& aPattern) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  nsresult rv;

  nsCOMPtr<mozIStorageFunction> function1(new OriginMatch(aPattern));
  rv = mDB->CreateFunction(NS_LITERAL_CSTRING("ORIGIN_MATCH"), 1, function1);
  NS_ENSURE_SUCCESS(rv, rv);

  class AutoRemoveFunc {
   public:
    mozIStorageConnection* mDB;
    explicit AutoRemoveFunc(mozIStorageConnection* aDB) : mDB(aDB) {}
    ~AutoRemoveFunc() {
      mDB->RemoveFunction(NS_LITERAL_CSTRING("ORIGIN_MATCH"));
    }
  };
  AutoRemoveFunc autoRemove(mDB);

  nsCOMPtr<mozIStorageStatement> statement;
  rv = mDB->CreateStatement(
      NS_LITERAL_CSTRING("SELECT GroupID, ActiveClientID FROM moz_cache_groups "
                         "WHERE ORIGIN_MATCH(GroupID);"),
      getter_AddRefs(statement));
  NS_ENSURE_SUCCESS(rv, rv);

  AutoResetStatement statementScope(statement);

  bool hasRows;
  rv = statement->ExecuteStep(&hasRows);
  NS_ENSURE_SUCCESS(rv, rv);

  while (hasRows) {
    nsAutoCString group;
    rv = statement->GetUTF8String(0, group);
    NS_ENSURE_SUCCESS(rv, rv);

    nsCString clientID;
    rv = statement->GetUTF8String(1, clientID);
    NS_ENSURE_SUCCESS(rv, rv);

    nsCOMPtr<nsIRunnable> ev =
        new nsOfflineCacheDiscardCache(this, group, clientID);

    rv = nsCacheService::DispatchToCacheIOThread(ev);
    NS_ENSURE_SUCCESS(rv, rv);

    rv = statement->ExecuteStep(&hasRows);
    NS_ENSURE_SUCCESS(rv, rv);
  }

  return NS_OK;
}

bool nsOfflineCacheDevice::CanUseCache(nsIURI* keyURI,
                                       const nsACString& clientID,
                                       nsILoadContextInfo* loadContextInfo) {
  {
    MutexAutoLock lock(mLock);
    if (!mActiveCaches.Contains(clientID)) return false;
  }

  nsAutoCString groupID;
  nsresult rv = GetGroupForCache(clientID, groupID);
  NS_ENSURE_SUCCESS(rv, false);

  nsCOMPtr<nsIURI> groupURI;
  rv = NS_NewURI(getter_AddRefs(groupURI), groupID);
  if (NS_FAILED(rv)) {
    return false;
  }

  // When we are choosing an initial cache to load the top
  // level document from, the URL of that document must have
  // the same origin as the manifest, according to the spec.
  // The following check is here because explicit, fallback
  // and dynamic entries might have origin different from the
  // manifest origin.
  if (!NS_SecurityCompareURIs(keyURI, groupURI, GetStrictFileOriginPolicy())) {
    return false;
  }

  // Check the groupID we found is equal to groupID based
  // on the load context demanding load from app cache.
  // This is check of extended origin.

  nsAutoCString originSuffix;
  loadContextInfo->OriginAttributesPtr()->CreateSuffix(originSuffix);

  nsAutoCString demandedGroupID;
  rv = BuildApplicationCacheGroupID(groupURI, originSuffix, demandedGroupID);
  NS_ENSURE_SUCCESS(rv, false);

  if (groupID != demandedGroupID) {
    return false;
  }

  return true;
}

nsresult nsOfflineCacheDevice::ChooseApplicationCache(
    const nsACString& key, nsILoadContextInfo* loadContextInfo,
    nsIApplicationCache** out) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  NS_ENSURE_ARG(loadContextInfo);

  nsresult rv;

  *out = nullptr;

  nsCOMPtr<nsIURI> keyURI;
  rv = NS_NewURI(getter_AddRefs(keyURI), key);
  NS_ENSURE_SUCCESS(rv, rv);

  // First try to find a matching cache entry.
  AutoResetStatement statement(mStatement_FindClient);
  rv = statement->BindUTF8StringByIndex(0, key);
  NS_ENSURE_SUCCESS(rv, rv);

  bool hasRows;
  rv = statement->ExecuteStep(&hasRows);
  NS_ENSURE_SUCCESS(rv, rv);

  while (hasRows) {
    int32_t itemType;
    rv = statement->GetInt32(1, &itemType);
    NS_ENSURE_SUCCESS(rv, rv);

    if (!(itemType & nsIApplicationCache::ITEM_FOREIGN)) {
      nsAutoCString clientID;
      rv = statement->GetUTF8String(0, clientID);
      NS_ENSURE_SUCCESS(rv, rv);

      if (CanUseCache(keyURI, clientID, loadContextInfo)) {
        return GetApplicationCache(clientID, out);
      }
    }

    rv = statement->ExecuteStep(&hasRows);
    NS_ENSURE_SUCCESS(rv, rv);
  }

  // OK, we didn't find an exact match.  Search for a client with a
  // matching namespace.

  AutoResetStatement nsstatement(mStatement_FindClientByNamespace);

  rv = nsstatement->BindUTF8StringByIndex(0, key);
  NS_ENSURE_SUCCESS(rv, rv);

  rv = nsstatement->ExecuteStep(&hasRows);
  NS_ENSURE_SUCCESS(rv, rv);

  while (hasRows) {
    int32_t itemType;
    rv = nsstatement->GetInt32(1, &itemType);
    NS_ENSURE_SUCCESS(rv, rv);

    // Don't associate with a cache based solely on a whitelist entry
    if (!(itemType & nsIApplicationCacheNamespace::NAMESPACE_BYPASS)) {
      nsAutoCString clientID;
      rv = nsstatement->GetUTF8String(0, clientID);
      NS_ENSURE_SUCCESS(rv, rv);

      if (CanUseCache(keyURI, clientID, loadContextInfo)) {
        return GetApplicationCache(clientID, out);
      }
    }

    rv = nsstatement->ExecuteStep(&hasRows);
    NS_ENSURE_SUCCESS(rv, rv);
  }

  return NS_OK;
}

nsresult nsOfflineCacheDevice::CacheOpportunistically(
    nsIApplicationCache* cache, const nsACString& key) {
  NS_ENSURE_ARG_POINTER(cache);

  nsresult rv;

  nsAutoCString clientID;
  rv = cache->GetClientID(clientID);
  NS_ENSURE_SUCCESS(rv, rv);

  return CacheOpportunistically(clientID, key);
}

nsresult nsOfflineCacheDevice::ActivateCache(const nsACString& group,
                                             const nsACString& clientID) {
  NS_ENSURE_TRUE(Initialized(), NS_ERROR_NOT_INITIALIZED);

  AutoResetStatement statement(mStatement_ActivateClient);
  nsresult rv = statement->BindUTF8StringByIndex(0, group);
  NS_ENSURE_SUCCESS(rv, rv);
  rv = statement->BindUTF8StringByIndex(1, clientID);
  NS_ENSURE_SUCCESS(rv, rv);
  rv = statement->BindInt32ByIndex(2, SecondsFromPRTime(PR_Now()));
  NS_ENSURE_SUCCESS(rv, rv);

  rv = statement->Execute();
  NS_ENSURE_SUCCESS(rv, rv);

  MutexAutoLock lock(mLock);

  nsCString* active;
  if (mActiveCachesByGroup.Get(group, &active)) {
    mActiveCaches.RemoveEntry(*active);
    mActiveCachesByGroup.Remove(group);
    active = nullptr;
  }

  if (!clientID.IsEmpty()) {
    mActiveCaches.PutEntry(clientID);
    mActiveCachesByGroup.Put(group, new nsCString(clientID));
  }

  return NS_OK;
}

bool nsOfflineCacheDevice::IsActiveCache(const nsACString& group,
                                         const nsACString& clientID) {
  nsCString* active = nullptr;
  MutexAutoLock lock(mLock);
  return mActiveCachesByGroup.Get(group, &active) && *active == clientID;
}

/**
 * Preference accessors
 */

void nsOfflineCacheDevice::SetCacheParentDirectory(nsIFile* parentDir) {
  if (Initialized()) {
    NS_ERROR("cannot switch cache directory once initialized");
    return;
  }

  if (!parentDir) {
    mCacheDirectory = nullptr;
    return;
  }

  // ensure parent directory exists
  nsresult rv = EnsureDir(parentDir);
  if (NS_FAILED(rv)) {
    NS_WARNING("unable to create parent directory");
    return;
  }

  mBaseDirectory = parentDir;

  // cache dir may not exist, but that's ok
  nsCOMPtr<nsIFile> dir;
  rv = parentDir->Clone(getter_AddRefs(dir));
  if (NS_FAILED(rv)) return;
  rv = dir->AppendNative(NS_LITERAL_CSTRING("OfflineCache"));
  if (NS_FAILED(rv)) return;

  mCacheDirectory = dir;
}

void nsOfflineCacheDevice::SetCapacity(uint32_t capacity) {
  mCacheCapacity = capacity * 1024;
}

bool nsOfflineCacheDevice::AutoShutdown(nsIApplicationCache* aAppCache) {
  if (!mAutoShutdown) return false;

  mAutoShutdown = false;

  Shutdown();

  nsCOMPtr<nsICacheService> serv = do_GetService(kCacheServiceCID);
  RefPtr<nsCacheService> cacheService = nsCacheService::GlobalInstance();
  cacheService->RemoveCustomOfflineDevice(this);

  nsAutoCString clientID;
  aAppCache->GetClientID(clientID);

  MutexAutoLock lock(mLock);
  mCaches.Remove(clientID);

  return true;
}