Write out CacheStorageCache size to index file.

content/browser/cache_storage/cache_storage_index.cc

+// Copyright 2016 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 "content/browser/cache_storage/cache_storage_index.h"
+
+#include <utility>
+
+namespace content {
+
+CacheStorageIndex::CacheStorageIndex(const CacheStorageIndex& other) {
+  for (const auto& cache_metadata : other.ordered_cache_metadata_)
+    Insert(cache_metadata);
+}
+
+CacheStorageIndex::CacheStorageIndex() = default;
+
+CacheStorageIndex::~CacheStorageIndex() = default;
+
+CacheStorageIndex& CacheStorageIndex::operator=(CacheStorageIndex&& rhs) {
+  ordered_cache_metadata_ = std::move(rhs.ordered_cache_metadata_);
+  cache_metadata_map_ = std::move(rhs.cache_metadata_map_);
+  storage_size_ = rhs.storage_size_;
+  rhs.storage_size_ = CacheStorage::kSizeUnknown;
+  return *this;
+}
+
+CacheStorageIndex& CacheStorageIndex::operator=(const CacheStorageIndex& rhs) {
+  ordered_cache_metadata_.clear();
+  cache_metadata_map_.clear();
+  for (const auto& metadata : rhs.ordered_cache_metadata_)
+    Insert(metadata);
+  storage_size_ = rhs.storage_size_;
+  return *this;
+}
+
+void CacheStorageIndex::Insert(const CacheMetadata& cache_metadata) {
+  DCHECK(cache_metadata_map_.find(cache_metadata.name) ==
+         cache_metadata_map_.end());
+  ordered_cache_metadata_.push_back(cache_metadata);
+  cache_metadata_map_[cache_metadata.name] = --ordered_cache_metadata_.end();
+  storage_size_ = CacheStorage::kSizeUnknown;
+}
+
+void CacheStorageIndex::Delete(const std::string& cache_name) {
+  auto it = cache_metadata_map_.find(cache_name);
+  DCHECK(it != cache_metadata_map_.end());
+  ordered_cache_metadata_.erase(it->second);
+  cache_metadata_map_.erase(it);
+  storage_size_ = CacheStorage::kSizeUnknown;
+}
+
+// Sets the cache size. Returns true if the new size is different than the
+// current size else false.
+bool CacheStorageIndex::SetCacheSize(const std::string& cache_name,
+                                     int64_t size) {
+  auto it = cache_metadata_map_.find(cache_name);
+  if (it == cache_metadata_map_.end()) {
+    // Deleted (but still referenced) caches can still run.

[jkarlin, 2016/12/01 17:43:31]

Hmm, this means that we might be getting a size update for a cache that's been
deleted. But there is nothing stopping a new cache with the same name from being
created. Which means that the doomed cache can update the size of the new cache!
That's a bug.

[cmumford, 2016/12/05 17:19:02]

Agreed. I added a check in CacheStorage::CacheSizeUpdated(), and only call this
if the cache is not doomed.

+    return false;
+  }
+  if (it->second->size == size)
+    return false;
+  it->second->size = size;
+  storage_size_ = CacheStorage::kSizeUnknown;
+  return true;
+}
+
+// The cache was modified, increasing/decreasing cache size by |size_delta|.
+void CacheStorageIndex::SetCacheSizeModified(const std::string& cache_name,

[jkarlin, 2016/12/01 17:43:31]

Is this still called?

[cmumford, 2016/12/05 17:19:02]

Only used by a lingering test - deleted it (and the test code).

+                                             int64_t size_delta) {
+  DCHECK_NE(size_delta, 0);
+
+  auto it = cache_metadata_map_.find(cache_name);
+  if (it == cache_metadata_map_.end()) {
+    // Deleted (but still referenced) caches can still run.
+    return;
+  }
+  DCHECK_NE(it->second->size, CacheStorage::kSizeUnknown);
+  it->second->size += size_delta;
+  DCHECK_GE(it->second->size, 0U);
+  if (storage_size_ == CacheStorage::kSizeUnknown)
+    return;
+  DCHECK_NE(storage_size_, CacheStorage::kSizeUnknown);
+  storage_size_ += size_delta;
+  DCHECK_GE(storage_size_, 0U);
+}
+
+int64_t CacheStorageIndex::GetCacheSize(const std::string& cache_name) const {
+  const auto& it = cache_metadata_map_.find(cache_name);
+  if (it == cache_metadata_map_.end())
+    return CacheStorage::kSizeUnknown;
+  return it->second->size;
+}
+
+int64_t CacheStorageIndex::GetStorageSize() {
+  if (storage_size_ == CacheStorage::kSizeUnknown)
+    UpdateStorageSize();
+  return storage_size_;
+}
+
+void CacheStorageIndex::UpdateStorageSize() {
+  int64_t storage_size = 0;
+  storage_size_ = CacheStorage::kSizeUnknown;
+  for (const CacheMetadata& info : ordered_cache_metadata_) {
+    if (info.size == CacheStorage::kSizeUnknown)
+      return;
+    storage_size += info.size;
+  }
+  storage_size_ = storage_size;
+}
+
+}  // namespace content