Implement QuotaTemporaryStorageEvictor.

webkit/quota/quota_temporary_storage_evictor.cc

+// Copyright (c) 2011 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 "webkit/quota/quota_temporary_storage_evictor.h"
+
+#include "webkit/quota/quota_client.h"
+#include "webkit/quota/quota_task.h"
+
+#include <vector>
+#include <list>
+
+namespace quota {
+
+QuotaTemporaryStorageEvictor::QuotaTemporaryStorageEvictor(
+    QuotaManager* manager,
+    QuotaDatabase* database,
+    scoped_refptr<base::MessageLoopProxy> db_message_loop)
+    : manager_(manager),
+      database_(database),
+      db_message_loop_(db_message_loop) {
+}
+
+QuotaTemporaryStorageEvictor::~QuotaTemporaryStorageEvictor() {}
+
+void QuotaTemporaryStorageEvictor::Start() {
+  scoped_refptr<EvictTask> task(
+      new EvictTask(manager_, database_, 10000, db_message_loop_));
+  task->Start();
+}
+
+class QuotaTemporaryStorageEvictor::EvictTask : public QuotaDelayedThreadTask {
+ public:
+  EvictTask(
+      QuotaManager* manager,
+      QuotaDatabase* database,
+      int64 delay_ms,
+      scoped_refptr<base::MessageLoopProxy> db_message_loop)
+      : QuotaDelayedThreadTask(manager, db_message_loop, delay_ms),
+        manager_(manager),
+        database_(database) {
+    DCHECK(database_);
+  }
+
+ protected:
+  virtual void RunOnTargetThread() OVERRIDE {

[kinuko, 2011/05/11 07:49:30]

This method can be in the Evictor?

[Dai Mikurube (NOT FULLTIME), 2011/05/11 11:23:50]

Moved.

+    /*
+  // Return least recently used origins whose used_count is <=
+  // |max_used_count| up to |num_origins_limit|.  If |max_used_count| is -1,
+  // it just returns LRU storages regardless of the used_count value.
+  // |num_origins_limit| must be > 0.
+  bool GetLRUOrigins(StorageType type, std::vector<GURL>* origins,
+                     int max_used_count, int num_origins_limit);
+    */
+    std::vector<GURL> origins;
+    database_->GetLRUOrigins(...);
+
+    QuotaClientList clients;
+    manager_->GetClients(...);
+
+    for (std::vector<GURL>::iterator p = origins.begin();
+         p != origins.end();
+         ++p) {
+      for (QuotaClientList::iterator q = clients.begin();
+           q != clients.end();
+           ++q) {

[kinuko, 2011/05/11 07:49:30]

Conceptually the main loop would look like that.

Some random thoughts... (you may have already considered some of them):
- the origin loop will need to be in a callback chain
- each client will throw a task to its preferable thread to delete its data, so
we'll need to collect/count callbacks to determine if one origin is completely
deleted
- when one origin is completely deleted we'll need to check if the remaining
available space looks good to go or if we'll need to run another deletion cycle
for the next origin.

Actually Database::GetLRUOrigins() might not fit very well to our model?
We may want to have the method that returns the least recently used one that are
not in a given 'in-use' origins list?

Database::GetLRUOrigin(vector<GURL> in_use_origins)

[Dai Mikurube (NOT FULLTIME), 2011/05/11 11:23:50]

Yeah, it was just a conceptual code.  Changed it with looking at
http://codereview.chromium.org/7003021/ .

+      }
+    }
+  }
+
+  virtual void Completed() OVERRIDE {
+  }
+
+ private:
+  QuotaManager* manager_;
+  QuotaDatabase* database_;
+};
+
+}  // namespace quota