**STILLBAKING** Decouple disk cache tests from backends.

net/disk_cache/v2/blockfile_unittest.cc

Index: net/disk_cache/v2/blockfile_unittest.cc
diff --git a/net/disk_cache/v2/blockfile_unittest.cc b/net/disk_cache/v2/blockfile_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..56c7fc995dfa0ea384c88b1275757a87489baf34
--- /dev/null
+++ b/net/disk_cache/v2/blockfile_unittest.cc
@@ -0,0 +1,1644 @@
+// Copyright (c) 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/file_util.h"
+#include "base/single_thread_task_runner.h"
+#include "base/strings/string_util.h"
+#include "base/strings/stringprintf.h"
+#include "base/threading/thread_restrictions.h"
+#include "base/memory/scoped_ptr.h"
+#include "net/base/test_completion_callback.h"
+#include "net/disk_cache/cache_util.h"
+#include "net/disk_cache/disk_cache_test.h"
+#include "net/disk_cache/disk_cache_test_util.h"
+#include "net/disk_cache/entry_tests.h"
+#include "net/disk_cache/backend_tests.h"
+#include "net/disk_cache/entry_sync_tests.h"
+#include "net/disk_cache/blockfile/backend_impl.h"
+#include "net/disk_cache/blockfile/entry_impl.h"
+
+#define CACHE_HISTOGRAM_MACROS_BACKEND_IMPL_OBJ backend_
+#include "net/disk_cache/blockfile/histogram_macros.h"
+
+namespace disk_cache {
+
+namespace {
+
+class BlockfileCacheCreateBackendExtraData
+    : public BackendTestTraits::CreateBackendExtraData {
+ public:
+  uint32 mask() const { return mask_; }
+  void set_mask(uint32 mask) { mask_ = mask; }
+
+ private:
+  friend class DiskCacheBlockfileBackendTest;
+
+  BlockfileCacheCreateBackendExtraData() : mask_(0) {}
+
+  uint32 mask_;
+};
+
+class BlockfileCacheBackendTraits : public BackendTestTraits {
+ public:
+  virtual ~BlockfileCacheBackendTraits() {}
+
+  virtual Backend* CreateBackend(
+      const CreateBackendExtraData* extra_data,
+      const base::FilePath& cache_path,
+      int max_size,
+      base::MessageLoopProxy* task_runner) const OVERRIDE {
+    const BlockfileCacheCreateBackendExtraData* blockfile_extra_data =
+        static_cast<const BlockfileCacheCreateBackendExtraData*>(extra_data);
+
+    scoped_ptr<BackendImpl> blockfile_backend;
+    if (blockfile_extra_data && blockfile_extra_data->mask()) {
+      blockfile_backend.reset(
+          new BackendImpl(cache_path, blockfile_extra_data->mask(),
+                          task_runner, NULL));
+    } else {
+      blockfile_backend.reset(new BackendImpl(cache_path, task_runner, NULL));
+    }
+    if (!blockfile_backend)
+      return NULL;
+
+    blockfile_backend->SetMaxSize(max_size);
+    if (flags_ & kNewEviction)
+      blockfile_backend->SetNewEviction();
+    blockfile_backend->SetFlags(flags_);
+    blockfile_backend->SetType(type_);
+
+    net::TestCompletionCallback cb;
+    int result = blockfile_backend->Init(cb.callback());
+    if (cb.GetResult(result) != net::OK) {
+      LOG(INFO) << "init failed :-(";
+      return NULL;
+    }
+    return blockfile_backend.release();
+  }
+
+  virtual bool UsesCacheThread() const OVERRIDE { return true; }
+  virtual bool WritesUpdateLastUsed() const OVERRIDE {
+    return type_ != net::APP_CACHE;
+  }
+  virtual bool ReadsUpdateLastUsed() const OVERRIDE {
+    return type_ != net::APP_CACHE && type_ != net::SHADER_CACHE;
+  }
+  virtual int SparseRoundingInterval() const OVERRIDE { return 1024; }
+  virtual bool EntryCountIncludesSparseRanges() const OVERRIDE {
+    return true;
+  }
+  virtual bool EnumerationsAreLexicographicByKey() const OVERRIDE {
+    return true;
+  }
+
+  virtual bool SetMaxSize(Backend* backend, int size) const OVERRIDE {
+    return static_cast<BackendImpl*>(backend)->SetMaxSize(size);
+  }
+
+  virtual void FlushQueueForTest(Backend* backend) const OVERRIDE {
+    BackendImpl* blockfile_backend = static_cast<BackendImpl*>(backend);
+
+    net::TestCompletionCallback cb;
+    int rv = blockfile_backend->FlushQueueForTest(cb.callback());
+    EXPECT_EQ(net::OK, cb.GetResult(rv));
+  }
+
+  net::CacheType type() const { return type_; }
+  uint32 flags() const { return flags_; }
+
+  // DiskCache(), AppCache() and ShaderCache() return traits objects for the
+  // entry unit tests.
+  static const BackendTestTraits* DiskCache() {
+    static const BlockfileCacheBackendTraits traits(net::DISK_CACHE, kNoRandom);
+    return &traits;
+  }
+
+  static const BackendTestTraits* AppCache() {
+    static const BlockfileCacheBackendTraits traits(net::APP_CACHE, kNoRandom);
+    return &traits;
+  }
+
+  static const BackendTestTraits* ShaderCache() {
+    static const BlockfileCacheBackendTraits traits(net::SHADER_CACHE,
+                                                    kNoRandom);
+    return &traits;
+  }
+
+  // OldEviction() and NewEviction() return traits objects for the backend
+  // unit tests.
+  static const BackendTestTraits* OldEviction() {
+    static const BlockfileCacheBackendTraits traits(net::DISK_CACHE, kNoRandom);
+    return &traits;
+  }
+
+  static const BackendTestTraits* NewEviction() {
+    static const BlockfileCacheBackendTraits traits(net::DISK_CACHE,
+                                                    kNoRandom | kNewEviction);
+    return &traits;
+  }
+
+ private:
+  BlockfileCacheBackendTraits(net::CacheType type,
+                              uint32 flags) : type_(type),
+                                              flags_(flags) {}
+
+  const net::CacheType type_;
+  const uint32 flags_;
+};
+
+// Run entry tests on DISK_CACHE, APP_CACHE and SHADER_CACHE type caches.
+INSTANTIATE_TEST_CASE_P(
+    BlockfileCache, DiskCacheEntryTest,
+    ::testing::Values(BlockfileCacheBackendTraits::DiskCache(),
+                      BlockfileCacheBackendTraits::AppCache(),
+                      BlockfileCacheBackendTraits::ShaderCache()));
+
+INSTANTIATE_TEST_CASE_P(
+    BlockfileCache, DiskCacheEntrySyncTest,
+    ::testing::Values(BlockfileCacheBackendTraits::DiskCache(),
+                      BlockfileCacheBackendTraits::AppCache(),
+                      BlockfileCacheBackendTraits::ShaderCache()));
+
+class DiskCacheBlockfileEntryTest : public DiskCacheTest {
+ protected:
+  BackendImpl* cache_impl() {
+    return static_cast<BackendImpl*>(DiskCacheTest::cache());
+  }
+};
+
+INSTANTIATE_TEST_CASE_P(
+    BlockfileCache, DiskCacheBlockfileEntryTest,
+    ::testing::Values(BlockfileCacheBackendTraits::DiskCache(),
+                      BlockfileCacheBackendTraits::AppCache(),
+                      BlockfileCacheBackendTraits::ShaderCache()));
+
+// Run backend tests using both the old and the new eviction algorithm.
+INSTANTIATE_TEST_CASE_P(
+    BlockfileCache, DiskCacheBackendTest,
+    ::testing::Values(BlockfileCacheBackendTraits::OldEviction(),
+                      BlockfileCacheBackendTraits::NewEviction()));
+
+
+class DiskCacheBlockfileBackendTest : public DiskCacheTest {
+ public:
+  BackendImpl* cache_impl() {
+    return static_cast<BackendImpl*>(DiskCacheTest::cache());
+  }
+
+  const BlockfileCacheBackendTraits* blockfile_traits() const {
+    return static_cast<const BlockfileCacheBackendTraits*>(
+        DiskCacheTest::traits());
+  }
+
+  void InitCache() {
+    InitCacheWithExtraData(&extra_data_);
+  }
+
+  void SimulateCrash() {
+    net::TestCompletionCallback cb;
+    int rv = cache_impl()->FlushQueueForTest(cb.callback());
+    ASSERT_EQ(net::OK, cb.GetResult(rv));
+    cache_impl()->ClearRefCountForTest();
+
+    //    cache_.reset();
+    //PECT_TRUE(CheckCacheIntegrity(cache_path_, new_eviction_, mask_));
+
+    InitCache();
+  }
+
+  void TrimForTest(bool empty) {
+    RunTaskForTest(base::Bind(&disk_cache::BackendImpl::TrimForTest,
+                              base::Unretained(cache_impl()),
+                              empty));
+  }
+
+  void TrimDeletedListForTest(bool empty) {
+    RunTaskForTest(base::Bind(&disk_cache::BackendImpl::TrimDeletedListForTest,
+                              base::Unretained(cache_impl()),
+                              empty));
+  }
+
+  BlockfileCacheCreateBackendExtraData* extra_data() { return &extra_data_; }
+
+  void SetMask(uint32 mask) {
+    extra_data()->set_mask(mask);
+  }
+
+ private:
+  void RunTaskForTest(const base::Closure& closure) {
+    net::TestCompletionCallback cb;
+    int rv = cache_impl()->RunTaskForTest(closure, cb.callback());
+    EXPECT_EQ(net::OK, cb.GetResult(rv));
+  }
+
+  BlockfileCacheCreateBackendExtraData extra_data_;
+};
+
+INSTANTIATE_TEST_CASE_P(
+    BlockfileCache, DiskCacheBlockfileBackendTest,
+    ::testing::Values(BlockfileCacheBackendTraits::OldEviction(),
+                      BlockfileCacheBackendTraits::NewEviction()));
+
+// Tests that we handle the content correctly when buffering, a feature of the
+// blockfile cache that permits fast responses to certain reads.
+TEST_P(DiskCacheBlockfileEntryTest, BlockfileBuffering) {
+  InitCache();
+
+  std::string key("the first key");
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry(key, &entry));
+
+  const int kSize = 200;
+  scoped_refptr<net::IOBuffer> buffer1(new net::IOBuffer(kSize));
+  scoped_refptr<net::IOBuffer> buffer2(new net::IOBuffer(kSize));
+  CacheTestFillBuffer(buffer1->data(), kSize, true);
+  CacheTestFillBuffer(buffer2->data(), kSize, true);
+
+  EXPECT_EQ(kSize, WriteData(entry, 1, 0, buffer1.get(), kSize, false));
+  entry->Close();
+
+  // Write a little more and read what we wrote before.
+  ASSERT_EQ(net::OK, OpenEntry(key, &entry));
+  EXPECT_EQ(kSize, WriteData(entry, 1, 5000, buffer1.get(), kSize, false));
+  EXPECT_EQ(kSize, ReadData(entry, 1, 0, buffer2.get(), kSize));
+  EXPECT_TRUE(!memcmp(buffer2->data(), buffer1->data(), kSize));
+
+  // Now go to an external file.
+  EXPECT_EQ(kSize, WriteData(entry, 1, 18000, buffer1.get(), kSize, false));
+  entry->Close();
+
+  // Write something else and verify old data.
+  ASSERT_EQ(net::OK, OpenEntry(key, &entry));
+  EXPECT_EQ(kSize, WriteData(entry, 1, 10000, buffer1.get(), kSize, false));
+  CacheTestFillBuffer(buffer2->data(), kSize, true);
+  EXPECT_EQ(kSize, ReadData(entry, 1, 5000, buffer2.get(), kSize));
+  EXPECT_TRUE(!memcmp(buffer2->data(), buffer1->data(), kSize));
+  CacheTestFillBuffer(buffer2->data(), kSize, true);
+  EXPECT_EQ(kSize, ReadData(entry, 1, 0, buffer2.get(), kSize));
+  EXPECT_TRUE(!memcmp(buffer2->data(), buffer1->data(), kSize));
+  CacheTestFillBuffer(buffer2->data(), kSize, true);
+  EXPECT_EQ(kSize, ReadData(entry, 1, 18000, buffer2.get(), kSize));
+  EXPECT_TRUE(!memcmp(buffer2->data(), buffer1->data(), kSize));
+
+  // Extend the file some more.
+  EXPECT_EQ(kSize, WriteData(entry, 1, 23000, buffer1.get(), kSize, false));
+  entry->Close();
+
+  // And now make sure that we can deal with data in both places (ram/disk).
+  ASSERT_EQ(net::OK, OpenEntry(key, &entry));
+  EXPECT_EQ(kSize, WriteData(entry, 1, 17000, buffer1.get(), kSize, false));
+
+  // We should not overwrite the data at 18000 with this.
+  EXPECT_EQ(kSize, WriteData(entry, 1, 19000, buffer1.get(), kSize, false));
+  CacheTestFillBuffer(buffer2->data(), kSize, true);
+  EXPECT_EQ(kSize, ReadData(entry, 1, 18000, buffer2.get(), kSize));
+  EXPECT_TRUE(!memcmp(buffer2->data(), buffer1->data(), kSize));
+  CacheTestFillBuffer(buffer2->data(), kSize, true);
+  EXPECT_EQ(kSize, ReadData(entry, 1, 17000, buffer2.get(), kSize));
+  EXPECT_TRUE(!memcmp(buffer2->data(), buffer1->data(), kSize));
+
+  EXPECT_EQ(kSize, WriteData(entry, 1, 22900, buffer1.get(), kSize, false));
+  CacheTestFillBuffer(buffer2->data(), kSize, true);
+  EXPECT_EQ(100, ReadData(entry, 1, 23000, buffer2.get(), kSize));
+  EXPECT_TRUE(!memcmp(buffer2->data(), buffer1->data() + 100, 100));
+
+  CacheTestFillBuffer(buffer2->data(), kSize, true);
+  EXPECT_EQ(100, ReadData(entry, 1, 23100, buffer2.get(), kSize));
+  EXPECT_TRUE(!memcmp(buffer2->data(), buffer1->data() + 100, 100));
+
+  // Extend the file again and read before without closing the entry.
+  EXPECT_EQ(kSize, WriteData(entry, 1, 25000, buffer1.get(), kSize, false));
+  EXPECT_EQ(kSize, WriteData(entry, 1, 45000, buffer1.get(), kSize, false));
+  CacheTestFillBuffer(buffer2->data(), kSize, true);
+  EXPECT_EQ(kSize, ReadData(entry, 1, 25000, buffer2.get(), kSize));
+  EXPECT_TRUE(!memcmp(buffer2->data(), buffer1->data(), kSize));
+  CacheTestFillBuffer(buffer2->data(), kSize, true);
+  EXPECT_EQ(kSize, ReadData(entry, 1, 45000, buffer2.get(), kSize));
+  EXPECT_TRUE(!memcmp(buffer2->data(), buffer1->data(), kSize));
+
+  entry->Close();
+}
+
+// Tests that we discard entries if the data is missing.
+TEST_P(DiskCacheBlockfileEntryTest, MissingData) {
+  InitCache();
+
+  std::string key("the first key");
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry(key, &entry));
+
+  // Write to an external file.
+  const int kSize = 20000;
+  scoped_refptr<net::IOBuffer> buffer(new net::IOBuffer(kSize));
+  CacheTestFillBuffer(buffer->data(), kSize, false);
+  EXPECT_EQ(kSize, WriteData(entry, 0, 0, buffer.get(), kSize, false));
+  entry->Close();
+  FlushQueueForTest();
+
+  disk_cache::Addr address(0x80000001);
+  base::FilePath name = cache_impl()->GetFileName(address);
+  EXPECT_TRUE(base::DeleteFile(name, false));
+
+  // Attempt to read the data.
+  ASSERT_EQ(net::OK, OpenEntry(key, &entry));
+  EXPECT_EQ(net::ERR_FILE_NOT_FOUND,
+            ReadData(entry, 0, 0, buffer.get(), kSize));
+  entry->Close();
+
+  // The entry should be gone.
+  ASSERT_NE(net::OK, OpenEntry(key, &entry));
+}
+
+// Tests that corrupt sparse children are removed automatically.
+TEST_P(DiskCacheBlockfileEntryTest, CleanupSparseEntry) {
+  InitCache();
+  std::string key("the first key");
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry(key, &entry));
+
+  const int kSize = 4 * 1024;
+  scoped_refptr<net::IOBuffer> buf1(new net::IOBuffer(kSize));
+  CacheTestFillBuffer(buf1->data(), kSize, false);
+
+  const int k1Meg = 1024 * 1024;
+  EXPECT_EQ(kSize, WriteSparseData(entry, 8192, buf1.get(), kSize));
+  EXPECT_EQ(kSize, WriteSparseData(entry, k1Meg + 8192, buf1.get(), kSize));
+  EXPECT_EQ(kSize, WriteSparseData(entry, 2 * k1Meg + 8192, buf1.get(), kSize));
+  entry->Close();
+  EXPECT_EQ(4, cache()->GetEntryCount());
+
+  void* iter = NULL;
+  int count = 0;
+  std::string child_key[2];
+  while (OpenNextEntry(&iter, &entry) == net::OK) {
+    ASSERT_TRUE(entry != NULL);
+    // Writing to an entry will alter the LRU list and invalidate the iterator.
+    if (entry->GetKey() != key && count < 2)
+      child_key[count++] = entry->GetKey();
+    entry->Close();
+  }
+  for (int i = 0; i < 2; i++) {
+    ASSERT_EQ(net::OK, OpenEntry(child_key[i], &entry));
+    // Overwrite the header's magic and signature.
+    EXPECT_EQ(12, WriteData(entry, 2, 0, buf1.get(), 12, false));
+    entry->Close();
+  }
+
+  EXPECT_EQ(4, cache()->GetEntryCount());
+  ASSERT_EQ(net::OK, OpenEntry(key, &entry));
+
+  // Two children should be gone. One while reading and one while writing.
+  EXPECT_EQ(0, ReadSparseData(entry, 2 * k1Meg + 8192, buf1.get(), kSize));
+  EXPECT_EQ(kSize, WriteSparseData(entry, k1Meg + 16384, buf1.get(), kSize));
+  EXPECT_EQ(0, ReadSparseData(entry, k1Meg + 8192, buf1.get(), kSize));
+
+  // We never touched this one.
+  EXPECT_EQ(kSize, ReadSparseData(entry, 8192, buf1.get(), kSize));
+  entry->Close();
+
+  // We re-created one of the corrupt children.
+  EXPECT_EQ(3, cache()->GetEntryCount());
+}
+
+TEST_P(DiskCacheBlockfileEntryTest, CancelSparseIO) {
+  UseCurrentThread();
+  InitCache();
+  std::string key("the first key");
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry(key, &entry));
+
+  const int kSize = 40 * 1024;
+  scoped_refptr<net::IOBuffer> buf(new net::IOBuffer(kSize));
+  CacheTestFillBuffer(buf->data(), kSize, false);
+
+  // This will open and write two "real" entries.
+  net::TestCompletionCallback cb1, cb2, cb3, cb4, cb5;
+  int rv = entry->WriteSparseData(
+      1024 * 1024 - 4096, buf.get(), kSize, cb1.callback());
+  EXPECT_EQ(net::ERR_IO_PENDING, rv);
+
+  int64 offset = 0;
+  rv = entry->GetAvailableRange(offset, kSize, &offset, cb5.callback());
+  rv = cb5.GetResult(rv);
+  if (!cb1.have_result()) {
+    // We may or may not have finished writing to the entry. If we have not,
+    // we cannot start another operation at this time.
+    EXPECT_EQ(net::ERR_CACHE_OPERATION_NOT_SUPPORTED, rv);
+  }
+
+  // We cancel the pending operation, and register multiple notifications.
+  entry->CancelSparseIO();
+  EXPECT_EQ(net::ERR_IO_PENDING, entry->ReadyForSparseIO(cb2.callback()));
+  EXPECT_EQ(net::ERR_IO_PENDING, entry->ReadyForSparseIO(cb3.callback()));
+  entry->CancelSparseIO();  // Should be a no op at this point.
+  EXPECT_EQ(net::ERR_IO_PENDING, entry->ReadyForSparseIO(cb4.callback()));
+
+  if (!cb1.have_result()) {
+    EXPECT_EQ(net::ERR_CACHE_OPERATION_NOT_SUPPORTED,
+              entry->ReadSparseData(
+                  offset, buf.get(), kSize, net::CompletionCallback()));
+    EXPECT_EQ(net::ERR_CACHE_OPERATION_NOT_SUPPORTED,
+              entry->WriteSparseData(
+                  offset, buf.get(), kSize, net::CompletionCallback()));
+  }
+
+  // Now see if we receive all notifications. Note that we should not be able
+  // to write everything (unless the timing of the system is really weird).
+  rv = cb1.WaitForResult();
+  EXPECT_TRUE(rv == 4096 || rv == kSize);
+  EXPECT_EQ(net::OK, cb2.WaitForResult());
+  EXPECT_EQ(net::OK, cb3.WaitForResult());
+  EXPECT_EQ(net::OK, cb4.WaitForResult());
+
+  rv = entry->GetAvailableRange(offset, kSize, &offset, cb5.callback());
+  EXPECT_EQ(0, cb5.GetResult(rv));
+  entry->Close();
+}
+
+// Tests that we perform sanity checks on an entry's key. Note that there are
+// other tests that exercise sanity checks by using saved corrupt files.
+TEST_P(DiskCacheBlockfileEntryTest, KeySanityCheck) {
+  UseCurrentThread();
+  InitCache();
+  std::string key("the first key");
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry(key, &entry));
+
+  disk_cache::EntryImpl* entry_impl =
+      static_cast<disk_cache::EntryImpl*>(entry);
+  disk_cache::EntryStore* store = entry_impl->entry()->Data();
+
+  // We have reserved space for a short key (one block), let's say that the key
+  // takes more than one block, and remove the NULLs after the actual key.
+  store->key_len = 800;
+  memset(store->key + key.size(), 'k', sizeof(store->key) - key.size());
+  entry_impl->entry()->set_modified();
+  entry->Close();
+
+  // We have a corrupt entry. Now reload it. We should NOT read beyond the
+  // allocated buffer here.
+  ASSERT_NE(net::OK, OpenEntry(key, &entry));
+  //DisableIntegrityCheck();
+}
+
+// Backend tests.
+
+// Tests that |BackendImpl| fails to initialize with a missing file.
+TEST_P(DiskCacheBlockfileBackendTest, CreateBackend_MissingFile) {
+  ASSERT_TRUE(CopyTestCache("bad_entry"));
+  base::FilePath filename = cache_path().AppendASCII("data_1");
+  base::DeleteFile(filename, false);
+  base::Thread cache_thread("CacheThread");
+  ASSERT_TRUE(cache_thread.StartWithOptions(
+      base::Thread::Options(base::MessageLoop::TYPE_IO, 0)));
+  net::TestCompletionCallback cb;
+
+  bool prev = base::ThreadRestrictions::SetIOAllowed(false);
+  scoped_ptr<disk_cache::BackendImpl> cache(new disk_cache::BackendImpl(
+      cache_path(), cache_thread.message_loop_proxy().get(), NULL));
+  int rv = cache->Init(cb.callback());
+  EXPECT_EQ(net::ERR_FAILED, cb.GetResult(rv));
+  base::ThreadRestrictions::SetIOAllowed(prev);
+
+  cache.reset();
+  DisableIntegrityCheck();
+}
+
+// TODO(gavinp): less lame.
+TEST_P(DiskCacheBlockfileBackendTest, TruncatedIndex) { 
+  base::FilePath index = cache_path().AppendASCII("index");
+  ASSERT_EQ(5, file_util::WriteFile(index, "hello", 5));
+
+  base::Thread cache_thread("CacheThread");
+  ASSERT_TRUE(cache_thread.StartWithOptions(
+      base::Thread::Options(base::MessageLoop::TYPE_IO, 0)));
+  net::TestCompletionCallback cb;
+
+  scoped_ptr<disk_cache::Backend> backend;
+  int rv =
+      disk_cache::CreateCacheBackend(net::DISK_CACHE,
+                                     net::CACHE_BACKEND_BLOCKFILE,
+                                     cache_path(),
+                                     0,
+                                     false,
+                                     cache_thread.message_loop_proxy().get(),
+                                     NULL,
+                                     &backend,
+                                     cb.callback());
+  ASSERT_NE(net::OK, cb.GetResult(rv));
+
+  ASSERT_FALSE(backend);
+}
+
+// Tests the chaining of an entry to the current head.
+TEST_P(DiskCacheBlockfileBackendTest, Chain) {
+  SetMask(0x1);  // 2-entry table.
+  SetMaxSize(0x3000);  // 12 kB.
+  InitCache();
+
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry("The first key", &entry));
+  entry->Close();
+  ASSERT_EQ(net::OK, CreateEntry("The Second key", &entry));
+  entry->Close();
+}
+
+TEST_P(DiskCacheBlockfileBackendTest, NewEvictionTrim) {
+  TEST_DISABLED_IF(
+      (blockfile_traits()->flags() & kNewEviction) != kNewEviction);
+  InitCache();
+
+  disk_cache::Entry* entry;
+  for (int i = 0; i < 100; i++) {
+    std::string name(base::StringPrintf("Key %d", i));
+    ASSERT_EQ(net::OK, CreateEntry(name, &entry));
+    entry->Close();
+    if (i < 90) {
+      // Entries 0 to 89 are in list 1; 90 to 99 are in list 0.
+      ASSERT_EQ(net::OK, OpenEntry(name, &entry));
+      entry->Close();
+    }
+  }
+
+  // The first eviction must come from list 1 (10% limit), the second must come
+  // from list 0.
+  TrimForTest(false);
+  EXPECT_NE(net::OK, OpenEntry("Key 0", &entry));
+  TrimForTest(false);
+  EXPECT_NE(net::OK, OpenEntry("Key 90", &entry));
+
+  // Double check that we still have the list tails.
+  ASSERT_EQ(net::OK, OpenEntry("Key 1", &entry));
+  entry->Close();
+  ASSERT_EQ(net::OK, OpenEntry("Key 91", &entry));
+  entry->Close();
+}
+
+TEST_P(DiskCacheBlockfileBackendTest, ExternalFiles) {
+  InitCache();
+  // First, let's create a file on the folder.
+  base::FilePath filename = cache_path().AppendASCII("f_000001");
+
+  const int kSize = 50;
+  scoped_refptr<net::IOBuffer> buffer1(new net::IOBuffer(kSize));
+  CacheTestFillBuffer(buffer1->data(), kSize, false);
+  ASSERT_EQ(kSize, file_util::WriteFile(filename, buffer1->data(), kSize));
+
+  // Now let's create a file with the cache.
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry("key", &entry));
+  ASSERT_EQ(0, WriteData(entry, 0, 20000, buffer1.get(), 0, false));
+  entry->Close();
+
+  // And verify that the first file is still there.
+  scoped_refptr<net::IOBuffer> buffer2(new net::IOBuffer(kSize));
+  ASSERT_EQ(kSize, base::ReadFile(filename, buffer2->data(), kSize));
+  EXPECT_EQ(0, memcmp(buffer1->data(), buffer2->data(), kSize));
+}
+
+// Before looking for invalid entries, let's check a valid entry.
+TEST_P(DiskCacheBlockfileBackendTest, ValidEntry) {
+  InitCache();
+
+  std::string key("Some key");
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry(key, &entry));
+
+  const int kSize = 50;
+  scoped_refptr<net::IOBuffer> buffer1(new net::IOBuffer(kSize));
+  memset(buffer1->data(), 0, kSize);
+  base::strlcpy(buffer1->data(), "And the data to save", kSize);
+  EXPECT_EQ(kSize, WriteData(entry, 0, 0, buffer1.get(), kSize, false));
+  entry->Close();
+  SimulateCrash();
+
+  ASSERT_EQ(net::OK, OpenEntry(key, &entry));
+
+  scoped_refptr<net::IOBuffer> buffer2(new net::IOBuffer(kSize));
+  memset(buffer2->data(), 0, kSize);
+  EXPECT_EQ(kSize, ReadData(entry, 0, 0, buffer2.get(), kSize));
+  entry->Close();
+  EXPECT_STREQ(buffer1->data(), buffer2->data());
+}
+
+// The same logic of the previous test (ValidEntry), but this time force the
+// entry to be invalid, simulating a crash in the middle.
+// We'll be leaking memory from this test.
+TEST_P(DiskCacheBlockfileBackendTest, InvalidEntry) {
+  InitCache();
+
+  std::string key("Some key");
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry(key, &entry));
+
+  const int kSize = 50;
+  scoped_refptr<net::IOBuffer> buffer(new net::IOBuffer(kSize));
+  memset(buffer->data(), 0, kSize);
+  base::strlcpy(buffer->data(), "And the data to save", kSize);
+  EXPECT_EQ(kSize, WriteData(entry, 0, 0, buffer.get(), kSize, false));
+  SimulateCrash();
+
+  EXPECT_NE(net::OK, OpenEntry(key, &entry));
+  EXPECT_EQ(0, cache()->GetEntryCount());
+}
+
+// Almost the same test, but this time crash the cache after reading an entry.
+// We'll be leaking memory from this test.
+TEST_P(DiskCacheBlockfileBackendTest, InvalidEntryRead) {
+  InitCache();
+
+  std::string key("Some key");
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry(key, &entry));
+
+  const int kSize = 50;
+  scoped_refptr<net::IOBuffer> buffer(new net::IOBuffer(kSize));
+  memset(buffer->data(), 0, kSize);
+  base::strlcpy(buffer->data(), "And the data to save", kSize);
+  EXPECT_EQ(kSize, WriteData(entry, 0, 0, buffer.get(), kSize, false));
+  entry->Close();
+  ASSERT_EQ(net::OK, OpenEntry(key, &entry));
+  EXPECT_EQ(kSize, ReadData(entry, 0, 0, buffer.get(), kSize));
+
+  SimulateCrash();
+
+  if (cache_impl()->cache_type() == net::APP_CACHE) {
+    // Reading an entry and crashing should not make it dirty.
+    ASSERT_EQ(net::OK, OpenEntry(key, &entry));
+    EXPECT_EQ(1, cache()->GetEntryCount());
+    entry->Close();
+  } else {
+    EXPECT_NE(net::OK, OpenEntry(key, &entry));
+    EXPECT_EQ(0, cache()->GetEntryCount());
+  }
+}
+
+// We'll be leaking memory from this test.
+TEST_P(DiskCacheBlockfileBackendTest, InvalidEntryWithLoad) {
+  // Work with a tiny index table (16 entries)
+  SetMask(0x1);  // 2-entry table.
+  SetMaxSize(0x100000);
+  InitCache();
+
+  int seed = static_cast<int>(base::Time::Now().ToInternalValue());
+  srand(seed);
+
+  const int kNumEntries = 100;
+  disk_cache::Entry* entries[kNumEntries];
+  for (int i = 0; i < kNumEntries; i++) {
+    std::string key = GenerateKey(true);
+    ASSERT_EQ(net::OK, CreateEntry(key, &entries[i]));
+  }
+  EXPECT_EQ(kNumEntries, cache()->GetEntryCount());
+
+  for (int i = 0; i < kNumEntries; i++) {
+    int source1 = rand() % kNumEntries;
+    int source2 = rand() % kNumEntries;
+    disk_cache::Entry* temp = entries[source1];
+    entries[source1] = entries[source2];
+    entries[source2] = temp;
+  }
+
+  std::string keys[kNumEntries];
+  for (int i = 0; i < kNumEntries; i++) {
+    keys[i] = entries[i]->GetKey();
+    if (i < kNumEntries / 2)
+      entries[i]->Close();
+  }
+
+  SimulateCrash();
+
+  for (int i = kNumEntries / 2; i < kNumEntries; i++) {
+    disk_cache::Entry* entry;
+    EXPECT_NE(net::OK, OpenEntry(keys[i], &entry));
+  }
+
+  for (int i = 0; i < kNumEntries / 2; i++) {
+    disk_cache::Entry* entry;
+    ASSERT_EQ(net::OK, OpenEntry(keys[i], &entry));
+    entry->Close();
+  }
+
+  EXPECT_EQ(kNumEntries / 2, cache()->GetEntryCount());
+}
+
+TEST_P(DiskCacheBlockfileBackendTest, TrimInvalidEntry) {
+  const int kSize = 0x3000;  // 12 kB
+  SetMaxSize(kSize * 10);
+  InitCache();
+
+  std::string first("some key");
+  std::string second("something else");
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry(first, &entry));
+
+  scoped_refptr<net::IOBuffer> buffer(new net::IOBuffer(kSize));
+  memset(buffer->data(), 0, kSize);
+  EXPECT_EQ(kSize, WriteData(entry, 0, 0, buffer.get(), kSize, false));
+
+  // Simulate a crash.
+  SimulateCrash();
+
+  ASSERT_EQ(net::OK, CreateEntry(second, &entry));
+  EXPECT_EQ(kSize, WriteData(entry, 0, 0, buffer.get(), kSize, false));
+
+  EXPECT_EQ(2, cache()->GetEntryCount());
+  SetMaxSize(kSize);
+  entry->Close();  // Trim the cache.
+  FlushQueueForTest();
+
+  // If we evicted the entry in less than 20mS, we have one entry in the cache;
+  // if it took more than that, we posted a task and we'll delete the second
+  // entry too.
+  base::MessageLoop::current()->RunUntilIdle();
+
+  // This may be not thread-safe in general, but for now it's OK so add some
+  // ThreadSanitizer annotations to ignore data races on cache_.
+  // See http://crbug.com/55970
+  ANNOTATE_IGNORE_READS_BEGIN();
+  EXPECT_GE(1, cache()->GetEntryCount());
+  ANNOTATE_IGNORE_READS_END();
+
+  EXPECT_NE(net::OK, OpenEntry(first, &entry));
+}
+
+// We'll be leaking memory from this test.
+TEST_P(DiskCacheBlockfileBackendTest, TrimInvalidEntry2) {
+  SetMask(0xf);  // 16-entry table.
+
+  const int kSize = 0x3000;  // 12 kB
+  SetMaxSize(kSize * 40);
+  InitCache();
+
+  scoped_refptr<net::IOBuffer> buffer(new net::IOBuffer(kSize));
+  memset(buffer->data(), 0, kSize);
+  disk_cache::Entry* entry;
+
+  // Writing 32 entries to this cache chains most of them.
+  for (int i = 0; i < 32; i++) {
+    std::string key(base::StringPrintf("some key %d", i));
+    ASSERT_EQ(net::OK, CreateEntry(key, &entry));
+    EXPECT_EQ(kSize, WriteData(entry, 0, 0, buffer.get(), kSize, false));
+    entry->Close();
+    ASSERT_EQ(net::OK, OpenEntry(key, &entry));
+    // Note that we are not closing the entries.
+  }
+
+  // Simulate a crash.
+  SimulateCrash();
+
+  ASSERT_EQ(net::OK, CreateEntry("Something else", &entry));
+  EXPECT_EQ(kSize, WriteData(entry, 0, 0, buffer.get(), kSize, false));
+
+  FlushQueueForTest();
+  EXPECT_EQ(33, cache()->GetEntryCount());
+  SetMaxSize(kSize);
+
+  // For the new eviction code, all corrupt entries are on the second list so
+  // they are not going away that easy.
+  //  if (new_eviction_) {
+    EXPECT_EQ(net::OK, DoomAllEntries());
+    //}
+
+  entry->Close();  // Trim the cache.
+  FlushQueueForTest();
+
+  // We may abort the eviction before cleaning up everything.
+  base::MessageLoop::current()->RunUntilIdle();
+  FlushQueueForTest();
+  // If it's not clear enough: we may still have eviction tasks running at this
+  // time, so the number of entries is changing while we read it.
+  ANNOTATE_IGNORE_READS_AND_WRITES_BEGIN();
+  EXPECT_GE(30, cache()->GetEntryCount());
+  ANNOTATE_IGNORE_READS_AND_WRITES_END();
+}
+
+void BackendTransaction(DiskCacheBlockfileBackendTest* test,
+                        const std::string& name,
+                        int num_entries, bool load) {
+  //  success_ = false;
+  ASSERT_TRUE(test->CopyTestCache(name));
+  //  DisableFirstCleanup();
+
+  uint32 mask;
+  if (load) {
+    mask = 0xf;
+    test->SetMaxSize(0x100000);
+  } else {
+    // Clear the settings from the previous run.
+    mask = 0;
+    test->SetMaxSize(0);
+  }
+  test->SetMask(mask);
+
+  test->InitCache();
+  ASSERT_EQ(num_entries + 1, test->cache()->GetEntryCount());
+
+  std::string key("the first key");
+  disk_cache::Entry* entry1;
+  ASSERT_NE(net::OK, test->OpenEntry(key, &entry1));
+
+  int actual = test->cache()->GetEntryCount();
+  if (num_entries != actual) {
+    ASSERT_TRUE(load);
+    // If there is a heavy load, inserting an entry will make another entry
+    // dirty (on the hash bucket) so two entries are removed.
+    ASSERT_EQ(num_entries - 1, actual);
+  }
+
+  //  test->cache().reset();
+  //  cache_impl_ = NULL;
+
+  //  ASSERT_TRUE(CheckCacheIntegrity(cache_path_, new_eviction_, mask));
+  //success_ = true;
+}
+
+TEST_P(DiskCacheBlockfileBackendTest, RecoverInsert) {
+  // Tests with an empty cache.
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "insert_empty1", 0, false));
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "insert_empty2", 0, false));
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "insert_empty3", 0, false));
+
+  // Tests with one entry on the cache.
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "insert_one1", 1, false));
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "insert_one2", 1, false));
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "insert_one3", 1, false));
+
+  // Tests with one hundred entries on the cache, tiny index.
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "insert_load1", 100, true));
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "insert_load2", 100, true));
+}
+
+TEST_P(DiskCacheBlockfileBackendTest, RecoverRemove) {
+  // Removing the only element.
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "remove_one1", 0, false));
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "remove_one2", 0, false));
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "remove_one3", 0, false));
+
+  // Removing the head.
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "remove_head1", 1, false));
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "remove_head2", 1, false));
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "remove_head3", 1, false));
+
+  // Removing the tail.
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "remove_tail1", 1, false));
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "remove_tail2", 1, false));
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "remove_tail3", 1, false));
+
+  // Removing with one hundred entries on the cache, tiny index.
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "remove_load1", 100, true));
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "remove_load2", 100, true));
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "remove_load3", 100, true));
+
+  // This case cannot be reverted.
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "remove_one4", 0, false));
+  ASSERT_NO_FATAL_FAILURE(BackendTransaction(this, "remove_head4", 1, false));
+}
+
+TEST_P(DiskCacheBlockfileBackendTest, RecoverWithEviction) {
+  ASSERT_TRUE(CopyTestCache("insert_load1"));
+  //DisableFirstCleanup();
+
+  SetMask(0xf);
+  SetMaxSize(0x1000);
+
+  // We should not crash here.
+  InitCache();
+  DisableIntegrityCheck();
+}
+
+// Tests that the |BackendImpl| fails to start with the wrong cache version.
+TEST_P(DiskCacheBlockfileBackendTest, WrongVersion) {
+  ASSERT_TRUE(CopyTestCache("wrong_version"));
+  base::Thread cache_thread("CacheThread");
+  ASSERT_TRUE(cache_thread.StartWithOptions(
+      base::Thread::Options(base::MessageLoop::TYPE_IO, 0)));
+  net::TestCompletionCallback cb;
+
+  scoped_ptr<disk_cache::BackendImpl> cache(new disk_cache::BackendImpl(
+      cache_path(), cache_thread.message_loop_proxy().get(), NULL));
+  int rv = cache->Init(cb.callback());
+  ASSERT_EQ(net::ERR_FAILED, cb.GetResult(rv));
+}
+
+#if 0
+// Tests that the cache is properly restarted on recovery error.
+TEST_P(DiskCacheBlockfileBackendTest, DeleteOld) {
+  ASSERT_TRUE(CopyTestCache("wrong_version"));
+  base::Thread cache_thread("CacheThread");
+  ASSERT_TRUE(cache_thread.StartWithOptions(
+      base::Thread::Options(base::MessageLoop::TYPE_IO, 0)));
+
+  net::TestCompletionCallback cb;
+  bool prev = base::ThreadRestrictions::SetIOAllowed(false);
+  base::FilePath path(cache_path());
+  int rv =
+      disk_cache::CreateCacheBackend(net::DISK_CACHE,
+                                     net::CACHE_BACKEND_BLOCKFILE,
+                                     path,
+                                     0,
+                                     true,
+                                     cache_thread.message_loop_proxy().get(),
+                                     NULL,
+                                     cache(),
+                                     cb.callback());
+  path.clear();  // Make sure path was captured by the previous call.
+  ASSERT_EQ(net::OK, cb.GetResult(rv));
+  base::ThreadRestrictions::SetIOAllowed(prev);
+  //  cache_.reset();
+  //EXPECT_TRUE(CheckCacheIntegrity(cache_path(), new_eviction_, mask_));
+}
+#endif
+
+// We want to be able to deal with messed up entries on disk.
+TEST_P(DiskCacheBlockfileBackendTest, InvalidEntry2) {
+  ASSERT_TRUE(CopyTestCache("bad_entry"));
+  //DisableFirstCleanup();
+  InitCache();
+
+  disk_cache::Entry *entry1, *entry2;
+  ASSERT_EQ(net::OK, OpenEntry("the first key", &entry1));
+  EXPECT_NE(net::OK, OpenEntry("some other key", &entry2));
+  entry1->Close();
+
+  // CheckCacheIntegrity will fail at this point.
+  //DisableIntegrityCheck();
+}
+
+// Tests that we don't crash or hang when enumerating this cache.
+TEST_P(DiskCacheBlockfileBackendTest, InvalidEntry3) {
+  SetMask(0x1);  // 2-entry table.
+  SetMaxSize(0x3000);  // 12 kB.
+  InitCache();
+
+  disk_cache::Entry* entry;
+  void* iter = NULL;
+  while (OpenNextEntry(&iter, &entry) == net::OK) {
+    entry->Close();
+  }
+}
+
+// Test that we handle a dirty entry on the LRU list, already replaced with
+// the same key, and with hash collisions.
+TEST_P(DiskCacheBlockfileBackendTest, InvalidEntry4) {
+  ASSERT_TRUE(CopyTestCache("dirty_entry3"));
+  SetMask(0x1);  // 2-entry table.
+  SetMaxSize(0x3000);  // 12 kB.
+  //DisableFirstCleanup();
+  InitCache();
+
+  TrimForTest(false);
+}
+
+// Test that we handle a dirty entry on the deleted list, already replaced with
+// the same key, and with hash collisions.
+TEST_P(DiskCacheBlockfileBackendTest, DISABLED_InvalidEntry5) {
+  ASSERT_TRUE(CopyTestCache("dirty_entry4"));
+  //  SetNewEviction();
+  SetMask(0x1);  // 2-entry table.
+  SetMaxSize(0x3000);  // 12 kB.
+  //DisableFirstCleanup();
+  InitCache();
+
+  TrimDeletedListForTest(false);
+}
+
+TEST_P(DiskCacheBlockfileBackendTest, InvalidEntry6) {
+  ASSERT_TRUE(CopyTestCache("dirty_entry5"));
+  SetMask(0x1);  // 2-entry table.
+  SetMaxSize(0x3000);  // 12 kB.
+  InitCache();
+
+  // There is a dirty entry (but marked as clean) at the end, pointing to a
+  // deleted entry through the hash collision list. We should not re-insert the
+  // deleted entry into the index table.
+
+  TrimForTest(false);
+  // The cache should be clean (as detected by CheckCacheIntegrity).
+}
+
+// Tests that we don't hang when there is a loop on the hash collision list.
+// The test cache could be a result of bug 69135.
+TEST_P(DiskCacheBlockfileBackendTest, BadNextEntry1) {
+  ASSERT_TRUE(CopyTestCache("list_loop2"));
+  SetMask(0x1);  // 2-entry table.
+  SetMaxSize(0x3000);  // 12 kB.
+  InitCache();
+
+  // The second entry points at itselft, and the first entry is not accessible
+  // though the index, but it is at the head of the LRU.
+
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry("The first key", &entry));
+  entry->Close();
+
+  TrimForTest(false);
+  TrimForTest(false);
+  ASSERT_EQ(net::OK, OpenEntry("The first key", &entry));
+  entry->Close();
+  EXPECT_EQ(1, cache()->GetEntryCount());
+}
+
+// Tests that we don't hang when there is a loop on the hash collision list.
+// The test cache could be a result of bug 69135.
+TEST_P(DiskCacheBlockfileBackendTest, BadNextEntry2) {
+  ASSERT_TRUE(CopyTestCache("list_loop3"));
+  SetMask(0x1);  // 2-entry table.
+  SetMaxSize(0x3000);  // 12 kB.
+  InitCache();
+
+  // There is a wide loop of 5 entries.
+
+  disk_cache::Entry* entry;
+  ASSERT_NE(net::OK, OpenEntry("Not present key", &entry));
+}
+
+TEST_P(DiskCacheBlockfileBackendTest, DISABLED_NewEvictionInvalidEntry6) {
+  ASSERT_TRUE(CopyTestCache("bad_rankings3"));
+  //DisableFirstCleanup();
+  //SetNewEviction();
+  InitCache();
+
+  // The second entry is dirty, but removing it should not corrupt the list.
+  disk_cache::Entry* entry;
+  ASSERT_NE(net::OK, OpenEntry("the second key", &entry));
+  ASSERT_EQ(net::OK, OpenEntry("the first key", &entry));
+
+  // This should not delete the cache.
+  entry->Doom();
+  FlushQueueForTest();
+  entry->Close();
+
+  ASSERT_EQ(net::OK, OpenEntry("some other key", &entry));
+  entry->Close();
+}
+
+// Tests handling of corrupt entries by keeping the rankings node around, with
+// a fatal failure.
+TEST_P(DiskCacheBlockfileBackendTest, InvalidEntry7) {
+  const int kSize = 0x3000;  // 12 kB.
+  SetMaxSize(kSize * 10);
+  InitCache();
+
+  std::string first("some key");
+  std::string second("something else");
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry(first, &entry));
+  entry->Close();
+  ASSERT_EQ(net::OK, CreateEntry(second, &entry));
+
+  // Corrupt this entry.
+  disk_cache::EntryImpl* entry_impl =
+      static_cast<disk_cache::EntryImpl*>(entry);
+
+  entry_impl->rankings()->Data()->next = 0;
+  entry_impl->rankings()->Store();
+  entry->Close();
+  FlushQueueForTest();
+  EXPECT_EQ(2, cache()->GetEntryCount());
+
+  // This should detect the bad entry.
+  EXPECT_NE(net::OK, OpenEntry(second, &entry));
+  EXPECT_EQ(1, cache()->GetEntryCount());
+
+  // We should delete the cache. The list still has a corrupt node.
+  void* iter = NULL;
+  EXPECT_NE(net::OK, OpenNextEntry(&iter, &entry));
+  FlushQueueForTest();
+  EXPECT_EQ(0, cache()->GetEntryCount());
+}
+
+// Tests handling of corrupt entries by keeping the rankings node around, with
+// a non fatal failure.
+TEST_P(DiskCacheBlockfileBackendTest, InvalidEntry8) {
+  const int kSize = 0x3000;  // 12 kB
+  SetMaxSize(kSize * 10);
+  InitCache();
+
+  std::string first("some key");
+  std::string second("something else");
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry(first, &entry));
+  entry->Close();
+  ASSERT_EQ(net::OK, CreateEntry(second, &entry));
+
+  // Corrupt this entry.
+  disk_cache::EntryImpl* entry_impl =
+      static_cast<disk_cache::EntryImpl*>(entry);
+
+  entry_impl->rankings()->Data()->contents = 0;
+  entry_impl->rankings()->Store();
+  entry->Close();
+  FlushQueueForTest();
+  EXPECT_EQ(2, cache()->GetEntryCount());
+
+  // This should detect the bad entry.
+  EXPECT_NE(net::OK, OpenEntry(second, &entry));
+  EXPECT_EQ(1, cache()->GetEntryCount());
+
+  // We should not delete the cache.
+  void* iter = NULL;
+  ASSERT_EQ(net::OK, OpenNextEntry(&iter, &entry));
+  entry->Close();
+  EXPECT_NE(net::OK, OpenNextEntry(&iter, &entry));
+  EXPECT_EQ(1, cache()->GetEntryCount());
+}
+
+#if 0
+// Tests handling of corrupt entries detected by enumerations.
+void DiskCacheBackendTest::BackendInvalidEntry10(bool eviction) {
+  const int kSize = 0x3000;  // 12 kB.
+  SetMaxSize(kSize * 10);
+  SetNewEviction();
+  InitCache();
+
+  std::string first("some key");
+  std::string second("something else");
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry(first, &entry));
+  entry->Close();
+  ASSERT_EQ(net::OK, OpenEntry(first, &entry));
+  EXPECT_EQ(0, WriteData(entry, 0, 200, NULL, 0, false));
+  entry->Close();
+  ASSERT_EQ(net::OK, CreateEntry(second, &entry));
+
+  // Corrupt this entry.
+  disk_cache::EntryImpl* entry_impl =
+      static_cast<disk_cache::EntryImpl*>(entry);
+
+  entry_impl->entry()->Data()->state = 0xbad;
+  entry_impl->entry()->Store();
+  entry->Close();
+  ASSERT_EQ(net::OK, CreateEntry("third", &entry));
+  entry->Close();
+  EXPECT_EQ(3, cache()->GetEntryCount());
+
+  // We have:
+  // List 0: third -> second (bad).
+  // List 1: first.
+
+  if (eviction) {
+    // Detection order: second -> first -> third.
+    TrimForTest(false);
+    EXPECT_EQ(3, cache()->GetEntryCount());
+    TrimForTest(false);
+    EXPECT_EQ(2, cache()->GetEntryCount());
+    TrimForTest(false);
+    EXPECT_EQ(1, cache()->GetEntryCount());
+  } else {
+    // Detection order: third -> second -> first.
+    // We should detect the problem through the list, but we should not delete
+    // the entry.
+    void* iter = NULL;
+    ASSERT_EQ(net::OK, OpenNextEntry(&iter, &entry));
+    entry->Close();
+    ASSERT_EQ(net::OK, OpenNextEntry(&iter, &entry));
+    EXPECT_EQ(first, entry->GetKey());
+    entry->Close();
+    EXPECT_NE(net::OK, OpenNextEntry(&iter, &entry));
+  }
+  DisableIntegrityCheck();
+}
+#endif
+
+// Tests handling of corrupt entries in the middle of a long eviction run.
+TEST_P(DiskCacheBlockfileBackendTest, TrimInvalidEntry12) {
+  const int kSize = 0x3000;  // 12 kB
+  SetMaxSize(kSize * 10);
+  InitCache();
+
+  std::string first("some key");
+  std::string second("something else");
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry(first, &entry));
+  entry->Close();
+  ASSERT_EQ(net::OK, CreateEntry(second, &entry));
+
+  // Corrupt this entry.
+  disk_cache::EntryImpl* entry_impl =
+      static_cast<disk_cache::EntryImpl*>(entry);
+
+  entry_impl->entry()->Data()->state = 0xbad;
+  entry_impl->entry()->Store();
+  entry->Close();
+  ASSERT_EQ(net::OK, CreateEntry("third", &entry));
+  entry->Close();
+  ASSERT_EQ(net::OK, CreateEntry("fourth", &entry));
+  TrimForTest(true);
+  EXPECT_EQ(1, cache()->GetEntryCount());
+  entry->Close();
+  DisableIntegrityCheck();
+}
+
+#if 0
+// If the LRU is corrupt, we delete the cache.
+void DiskCacheBackendTest::BackendInvalidRankings() {
+  disk_cache::Entry* entry;
+  void* iter = NULL;
+  ASSERT_EQ(net::OK, OpenNextEntry(&iter, &entry));
+  entry->Close();
+  EXPECT_EQ(2, cache()->GetEntryCount());
+
+  EXPECT_NE(net::OK, OpenNextEntry(&iter, &entry));
+  FlushQueueForTest();  // Allow the restart to finish.
+  EXPECT_EQ(0, cache()->GetEntryCount());
+}
+#endif
+
+// We want to be able to deal with messed up entries on disk.
+TEST_P(DiskCacheBlockfileBackendTest, InvalidRankings2) {
+  ASSERT_TRUE(CopyTestCache("bad_rankings"));
+  InitCache();
+
+  disk_cache::Entry *entry1, *entry2;
+  EXPECT_NE(net::OK, OpenEntry("the first key", &entry1));
+  ASSERT_EQ(net::OK, OpenEntry("some other key", &entry2));
+  entry2->Close();
+
+  // CheckCacheIntegrity will fail at this point.
+  DisableIntegrityCheck();
+}
+
+// If the index size changes when we disable the cache, we should not crash.
+TEST_P(DiskCacheBlockfileBackendTest, DisableSucess3) {
+  ASSERT_TRUE(CopyTestCache("bad_rankings"));
+  InitCache();
+
+  disk_cache::Entry *entry1, *entry2;
+  void* iter = NULL;
+  EXPECT_EQ(2, cache()->GetEntryCount());
+  ASSERT_EQ(net::OK, OpenNextEntry(&iter, &entry1));
+  entry1->Close();
+
+  EXPECT_NE(net::OK, OpenNextEntry(&iter, &entry2));
+  FlushQueueForTest();
+
+  ASSERT_EQ(net::OK, CreateEntry("Something new", &entry2));
+  entry2->Close();
+
+  EXPECT_EQ(1, cache()->GetEntryCount());
+}
+
+// If we disable the cache, already open entries should work as far as possible.
+TEST_P(DiskCacheBlockfileBackendTest, DisableSuccess4) {
+  ASSERT_TRUE(CopyTestCache("bad_rankings"));
+  InitCache();
+
+  disk_cache::Entry *entry1, *entry2, *entry3, *entry4;
+  void* iter = NULL;
+  ASSERT_EQ(net::OK, OpenNextEntry(&iter, &entry1));
+
+  char key2[2000];
+  char key3[20000];
+  CacheTestFillBuffer(key2, sizeof(key2), true);
+  CacheTestFillBuffer(key3, sizeof(key3), true);
+  key2[sizeof(key2) - 1] = '\0';
+  key3[sizeof(key3) - 1] = '\0';
+  ASSERT_EQ(net::OK, CreateEntry(key2, &entry2));
+  ASSERT_EQ(net::OK, CreateEntry(key3, &entry3));
+
+  const int kBufSize = 20000;
+  scoped_refptr<net::IOBuffer> buf(new net::IOBuffer(kBufSize));
+  memset(buf->data(), 0, kBufSize);
+  EXPECT_EQ(100, WriteData(entry2, 0, 0, buf.get(), 100, false));
+  EXPECT_EQ(kBufSize, WriteData(entry3, 0, 0, buf.get(), kBufSize, false));
+
+  // This line should disable the cache but not delete it.
+  EXPECT_NE(net::OK, OpenNextEntry(&iter, &entry4));
+  EXPECT_EQ(0, cache()->GetEntryCount());
+
+  EXPECT_NE(net::OK, CreateEntry("cache is disabled", &entry4));
+
+  EXPECT_EQ(100, ReadData(entry2, 0, 0, buf.get(), 100));
+  EXPECT_EQ(100, WriteData(entry2, 0, 0, buf.get(), 100, false));
+  EXPECT_EQ(100, WriteData(entry2, 1, 0, buf.get(), 100, false));
+
+  EXPECT_EQ(kBufSize, ReadData(entry3, 0, 0, buf.get(), kBufSize));
+  EXPECT_EQ(kBufSize, WriteData(entry3, 0, 0, buf.get(), kBufSize, false));
+  EXPECT_EQ(kBufSize, WriteData(entry3, 1, 0, buf.get(), kBufSize, false));
+
+  std::string key = entry2->GetKey();
+  EXPECT_EQ(sizeof(key2) - 1, key.size());
+  key = entry3->GetKey();
+  EXPECT_EQ(sizeof(key3) - 1, key.size());
+
+  entry1->Close();
+  entry2->Close();
+  entry3->Close();
+  FlushQueueForTest();  // Flushing the Close posts a task to restart the cache.
+  FlushQueueForTest();  // This one actually allows that task to complete.
+
+  EXPECT_EQ(0, cache()->GetEntryCount());
+}
+
+TEST_P(DiskCacheBlockfileBackendTest, UsageStatsTimer) {
+  MessageLoopHelper helper;
+
+  ASSERT_TRUE(CleanupCacheDir());
+  scoped_ptr<disk_cache::BackendImpl> cache;
+  cache.reset(new disk_cache::BackendImpl(
+      cache_path(), base::MessageLoopProxy::current().get(), NULL));
+  ASSERT_TRUE(NULL != cache.get());
+  cache->SetUnitTestMode();
+  ASSERT_EQ(net::OK, cache->SyncInit());
+
+  // Wait for a callback that never comes... about 2 secs :). The message loop
+  // has to run to allow invocation of the usage timer.
+  helper.WaitUntilCacheIoFinished(1);
+}
+
+TEST_P(DiskCacheBlockfileBackendTest, TimerNotCreated) {
+  ASSERT_TRUE(CopyTestCache("wrong_version"));
+
+  scoped_ptr<disk_cache::BackendImpl> cache;
+  cache.reset(new disk_cache::BackendImpl(
+      cache_path(), base::MessageLoopProxy::current().get(), NULL));
+  ASSERT_TRUE(NULL != cache.get());
+  cache->SetUnitTestMode();
+  ASSERT_NE(net::OK, cache->SyncInit());
+
+  ASSERT_TRUE(NULL == cache->GetTimerForTest());
+
+  DisableIntegrityCheck();
+}
+
+TEST_P(DiskCacheBlockfileBackendTest, UsageStats) {
+  InitCache();
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry("key", &entry));
+  entry->Close();
+  FlushQueueForTest();
+
+  disk_cache::StatsItems stats;
+  cache()->GetStats(&stats);
+  EXPECT_FALSE(stats.empty());
+
+  disk_cache::StatsItems::value_type hits("Create hit", "0x1");
+  EXPECT_EQ(1, std::count(stats.begin(), stats.end(), hits));
+
+  //  cache().reset();
+
+  // Now open the cache and verify that the stats are still there.
+  //DisableFirstCleanup();
+
+  InitCache();
+  EXPECT_EQ(1, cache()->GetEntryCount());
+
+  stats.clear();
+  cache()->GetStats(&stats);
+  EXPECT_FALSE(stats.empty());
+
+  EXPECT_EQ(1, std::count(stats.begin(), stats.end(), hits));
+}
+
+// If the index size changes when we doom the cache, we should not crash.
+TEST_P(DiskCacheBlockfileBackendTest, DoomAll2) {
+  ASSERT_TRUE(CopyTestCache("bad_rankings2"));
+  SetMaxSize(20 * 1024 * 1024);
+  InitCache();
+
+  EXPECT_EQ(2, cache()->GetEntryCount());
+  EXPECT_EQ(net::OK, DoomAllEntries());
+
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry("Something new", &entry));
+  entry->Close();
+
+  EXPECT_EQ(1, cache()->GetEntryCount());
+}
+
+// We should be able to create the same entry on multiple simultaneous instances
+// of the cache.
+TEST_P(DiskCacheBlockfileBackendTest, MultipleInstances) {
+  base::ScopedTempDir store1, store2;
+  ASSERT_TRUE(store1.CreateUniqueTempDir());
+  ASSERT_TRUE(store2.CreateUniqueTempDir());
+
+  base::Thread cache_thread("CacheThread");
+  ASSERT_TRUE(cache_thread.StartWithOptions(
+      base::Thread::Options(base::MessageLoop::TYPE_IO, 0)));
+  net::TestCompletionCallback cb;
+
+  const int kNumberOfCaches = 2;
+  scoped_ptr<disk_cache::Backend> cache[kNumberOfCaches];
+
+  int rv =
+      disk_cache::CreateCacheBackend(net::DISK_CACHE,
+                                     net::CACHE_BACKEND_DEFAULT,
+                                     store1.path(),
+                                     0,
+                                     false,
+                                     cache_thread.message_loop_proxy().get(),
+                                     NULL,
+                                     &cache[0],
+                                     cb.callback());
+  ASSERT_EQ(net::OK, cb.GetResult(rv));
+  rv = disk_cache::CreateCacheBackend(net::MEDIA_CACHE,
+                                      net::CACHE_BACKEND_DEFAULT,
+                                      store2.path(),
+                                      0,
+                                      false,
+                                      cache_thread.message_loop_proxy().get(),
+                                      NULL,
+                                      &cache[1],
+                                      cb.callback());
+  ASSERT_EQ(net::OK, cb.GetResult(rv));
+
+  ASSERT_TRUE(cache[0].get() != NULL && cache[1].get() != NULL);
+
+  std::string key("the first key");
+  disk_cache::Entry* entry;
+  for (int i = 0; i < kNumberOfCaches; i++) {
+    rv = cache[i]->CreateEntry(key, &entry, cb.callback());
+    ASSERT_EQ(net::OK, cb.GetResult(rv));
+    entry->Close();
+  }
+}
+
+// Test the six regions of the curve that determines the max cache size.
+TEST_P(DiskCacheBlockfileBackendTest, AutomaticMaxSize) {
+  using disk_cache::kDefaultCacheSize;
+  int64 large_size = kDefaultCacheSize;
+
+  // Region 1: expected = available * 0.8
+  EXPECT_EQ((kDefaultCacheSize - 1) * 8 / 10,
+            disk_cache::PreferredCacheSize(large_size - 1));
+  EXPECT_EQ(kDefaultCacheSize * 8 / 10,
+            disk_cache::PreferredCacheSize(large_size));
+  EXPECT_EQ(kDefaultCacheSize - 1,
+            disk_cache::PreferredCacheSize(large_size * 10 / 8 - 1));
+
+  // Region 2: expected = default_size
+  EXPECT_EQ(kDefaultCacheSize,
+            disk_cache::PreferredCacheSize(large_size * 10 / 8));
+  EXPECT_EQ(kDefaultCacheSize,
+            disk_cache::PreferredCacheSize(large_size * 10 - 1));
+
+  // Region 3: expected = available * 0.1
+  EXPECT_EQ(kDefaultCacheSize,
+            disk_cache::PreferredCacheSize(large_size * 10));
+  EXPECT_EQ((kDefaultCacheSize * 25 - 1) / 10,
+            disk_cache::PreferredCacheSize(large_size * 25 - 1));
+
+  // Region 4: expected = default_size * 2.5
+  EXPECT_EQ(kDefaultCacheSize * 25 / 10,
+            disk_cache::PreferredCacheSize(large_size * 25));
+  EXPECT_EQ(kDefaultCacheSize * 25 / 10,
+            disk_cache::PreferredCacheSize(large_size * 100 - 1));
+  EXPECT_EQ(kDefaultCacheSize * 25 / 10,
+            disk_cache::PreferredCacheSize(large_size * 100));
+  EXPECT_EQ(kDefaultCacheSize * 25 / 10,
+            disk_cache::PreferredCacheSize(large_size * 250 - 1));
+
+  // Region 5: expected = available * 0.1
+  int64 largest_size = kDefaultCacheSize * 4;
+  EXPECT_EQ(kDefaultCacheSize * 25 / 10,
+            disk_cache::PreferredCacheSize(large_size * 250));
+  EXPECT_EQ(largest_size - 1,
+            disk_cache::PreferredCacheSize(largest_size * 100 - 1));
+
+  // Region 6: expected = largest possible size
+  EXPECT_EQ(largest_size,
+            disk_cache::PreferredCacheSize(largest_size * 100));
+  EXPECT_EQ(largest_size,
+            disk_cache::PreferredCacheSize(largest_size * 10000));
+}
+
+// Tests that we can "migrate" a running instance from one experiment group to
+// another.
+TEST_P(DiskCacheBlockfileBackendTest, Histograms) {
+  InitCache();
+  disk_cache::BackendImpl* backend_ = cache_impl();  // Needed be the macro.
+
+  for (int i = 1; i < 3; i++) {
+    CACHE_UMA(HOURS, "FillupTime", i, 28);
+  }
+}
+
+// Make sure that we keep the total memory used by the internal buffers under
+// control.
+TEST_P(DiskCacheBlockfileBackendTest, TotalBuffersSize1) {
+  InitCache();
+  std::string key("the first key");
+  disk_cache::Entry* entry;
+  ASSERT_EQ(net::OK, CreateEntry(key, &entry));
+
+  const int kSize = 200;
+  scoped_refptr<net::IOBuffer> buffer(new net::IOBuffer(kSize));
+  CacheTestFillBuffer(buffer->data(), kSize, true);
+
+  for (int i = 0; i < 10; i++) {
+    SCOPED_TRACE(i);
+    // Allocate 2MB for this entry.
+    EXPECT_EQ(kSize, WriteData(entry, 0, 0, buffer.get(), kSize, true));
+    EXPECT_EQ(kSize, WriteData(entry, 1, 0, buffer.get(), kSize, true));
+    EXPECT_EQ(kSize,
+              WriteData(entry, 0, 1024 * 1024, buffer.get(), kSize, false));
+    EXPECT_EQ(kSize,
+              WriteData(entry, 1, 1024 * 1024, buffer.get(), kSize, false));
+
+    // Delete one of the buffers and truncate the other.
+    EXPECT_EQ(0, WriteData(entry, 0, 0, buffer.get(), 0, true));
+    EXPECT_EQ(0, WriteData(entry, 1, 10, buffer.get(), 0, true));
+
+    // Delete the second buffer, writing 10 bytes to disk.
+    entry->Close();
+    ASSERT_EQ(net::OK, OpenEntry(key, &entry));
+  }
+
+  entry->Close();
+  EXPECT_EQ(0, cache_impl()->GetTotalBuffersSize());
+}
+
+// This test assumes at least 150MB of system memory.
+TEST_P(DiskCacheBlockfileBackendTest, TotalBuffersSize2) {
+  InitCache();
+
+  const int kOneMB = 1024 * 1024;
+  EXPECT_TRUE(cache_impl()->IsAllocAllowed(0, kOneMB));
+  EXPECT_EQ(kOneMB, cache_impl()->GetTotalBuffersSize());
+
+  EXPECT_TRUE(cache_impl()->IsAllocAllowed(0, kOneMB));
+  EXPECT_EQ(kOneMB * 2, cache_impl()->GetTotalBuffersSize());
+
+  EXPECT_TRUE(cache_impl()->IsAllocAllowed(0, kOneMB));
+  EXPECT_EQ(kOneMB * 3, cache_impl()->GetTotalBuffersSize());
+
+  cache_impl()->BufferDeleted(kOneMB);
+  EXPECT_EQ(kOneMB * 2, cache_impl()->GetTotalBuffersSize());
+
+  // Check the upper limit.
+  EXPECT_FALSE(cache_impl()->IsAllocAllowed(0, 30 * kOneMB));
+
+  for (int i = 0; i < 30; i++)
+    cache_impl()->IsAllocAllowed(0, kOneMB);  // Ignore the result.
+
+  EXPECT_FALSE(cache_impl()->IsAllocAllowed(0, kOneMB));
+}
+
+// Tests that sharing of external files works and we are able to delete the
+// files when we need to.
+TEST_P(DiskCacheBlockfileBackendTest, FileSharing) {
+  InitCache();
+
+  disk_cache::Addr address(0x80000001);
+  ASSERT_TRUE(cache_impl()->CreateExternalFile(&address));
+  base::FilePath name = cache_impl()->GetFileName(address);
+
+  scoped_refptr<disk_cache::File> file(new disk_cache::File(false));
+  file->Init(name);
+
+#if defined(OS_WIN)
+  DWORD sharing = FILE_SHARE_READ | FILE_SHARE_WRITE;
+  DWORD access = GENERIC_READ | GENERIC_WRITE;
+  base::win::ScopedHandle file2(CreateFile(
+      name.value().c_str(), access, sharing, NULL, OPEN_EXISTING, 0, NULL));
+  EXPECT_FALSE(file2.IsValid());
+
+  sharing |= FILE_SHARE_DELETE;
+  file2.Set(CreateFile(name.value().c_str(), access, sharing, NULL,
+                       OPEN_EXISTING, 0, NULL));
+  EXPECT_TRUE(file2.IsValid());
+#endif
+
+  EXPECT_TRUE(base::DeleteFile(name, false));
+
+  // We should be able to use the file.
+  const int kSize = 200;
+  char buffer1[kSize];
+  char buffer2[kSize];
+  memset(buffer1, 't', kSize);
+  memset(buffer2, 0, kSize);
+  EXPECT_TRUE(file->Write(buffer1, kSize, 0));
+  EXPECT_TRUE(file->Read(buffer2, kSize, 0));
+  EXPECT_EQ(0, memcmp(buffer1, buffer2, kSize));
+
+  EXPECT_TRUE(disk_cache::DeleteCacheFile(name));
+}
+
+TEST_P(DiskCacheBlockfileBackendTest, UpdateRankForExternalCacheHit) {
+  InitCache();
+
+  disk_cache::Entry* entry;
+
+  for (int i = 0; i < 2; ++i) {
+    std::string key = base::StringPrintf("key%d", i);
+    ASSERT_EQ(net::OK, CreateEntry(key, &entry));
+    entry->Close();
+  }
+
+  // Ping the oldest entry.
+  cache()->OnExternalCacheHit("key0");
+
+  TrimForTest(false);
+
+  // Make sure the older key remains.
+  EXPECT_EQ(1, cache()->GetEntryCount());
+  ASSERT_EQ(net::OK, OpenEntry("key0", &entry));
+  entry->Close();
+}
+
+}  // namespace
+
+}  // namespace disk_cache