| /* |
| * Copyright 2010 Google Inc. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| // Author: jmarantz@google.com (Joshua Marantz) |
| |
| #include "pagespeed/kernel/cache/write_through_cache.h" |
| |
| #include <cstddef> |
| |
| #include "pagespeed/kernel/base/shared_string.h" |
| #include "pagespeed/kernel/base/string.h" |
| #include "pagespeed/kernel/cache/cache_interface.h" |
| |
| namespace net_instaweb { |
| |
| const size_t WriteThroughCache::kUnlimited = static_cast<size_t>(-1); |
| |
| WriteThroughCache::~WriteThroughCache() { |
| } |
| |
| void WriteThroughCache::PutInCache1(const GoogleString& key, |
| SharedString* value) { |
| if ((cache1_size_limit_ == kUnlimited) || |
| (key.size() + value->size() < cache1_size_limit_)) { |
| cache1_->Put(key, value); |
| } |
| } |
| |
| class WriteThroughCallback : public CacheInterface::Callback { |
| public: |
| WriteThroughCallback(WriteThroughCache* wtc, |
| const GoogleString& key, |
| CacheInterface::Callback* callback) |
| : write_through_cache_(wtc), |
| key_(key), |
| callback_(callback), |
| trying_cache2_(false) { |
| } |
| |
| virtual bool ValidateCandidate(const GoogleString& key, |
| CacheInterface::KeyState state) { |
| *callback_->value() = *value(); |
| return callback_->DelegatedValidateCandidate(key, state); |
| } |
| |
| virtual void Done(CacheInterface::KeyState state) { |
| if (state == CacheInterface::kAvailable) { |
| if (trying_cache2_) { |
| write_through_cache_->PutInCache1(key_, value()); |
| } |
| callback_->DelegatedDone(state); |
| delete this; |
| } else if (trying_cache2_) { |
| callback_->DelegatedDone(state); |
| delete this; |
| } else { |
| trying_cache2_ = true; |
| write_through_cache_->cache2()->Get(key_, this); |
| } |
| } |
| |
| |
| WriteThroughCache* write_through_cache_; |
| GoogleString key_; |
| CacheInterface::Callback* callback_; |
| bool trying_cache2_; |
| }; |
| |
| GoogleString WriteThroughCache::FormatName(StringPiece cache1, |
| StringPiece cache2) { |
| return StrCat("WriteThroughCache(l1=", cache1, ",l2=", cache2, ")"); |
| } |
| |
| void WriteThroughCache::Get(const GoogleString& key, Callback* callback) { |
| cache1_->Get(key, new WriteThroughCallback(this, key, callback)); |
| } |
| |
| void WriteThroughCache::Put(const GoogleString& key, SharedString* value) { |
| PutInCache1(key, value); |
| cache2_->Put(key, value); |
| } |
| |
| void WriteThroughCache::Delete(const GoogleString& key) { |
| cache1_->Delete(key); |
| cache2_->Delete(key); |
| } |
| |
| } // namespace net_instaweb |