ServiceWorker: Migrate the script cache backend from BlockFile to Simple

content/browser/service_worker/service_worker_database.cc

 // Copyright 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 "content/browser/service_worker/service_worker_database.h"
 
 #include "base/files/file_util.h"
 #include "base/lazy_instance.h"
 #include "base/location.h"
 #include "base/logging.h"
@@ skipping 55 matching lines @@
 //     (ex. "RES:123456\x00654321")
 //   value: <ServiceWorkerResourceRecord serialized as a string>
 //
 //   key: "URES:" + <int64 'uncommitted_resource_id'>
 //   value: <empty>
 //
 // Version 2
 //
 //   key: "REGID_TO_ORIGIN:" + <int64 'registration_id'>
 //   value: <GURL 'origin'>
+//
+//   key: "INITDATA_DISKCACHE_MIGRATION_NOT_NEEDED"
+//   value: <empty>
+//     - This entry represents that the diskcache uses the Simple backend and
+//       does not have to do diskcache migration (http://crbug.com/487482).
+//
+//   key: "INITDATA_OLD_DISKCACHE_DELETION_NOT_NEEDED"
+//   value: <empty>
+//     - This entry represents that the old BlockFile diskcache was deleted
+//       after diskcache migration (http://crbug.com/487482).
 namespace content {
 
 namespace {
 
 const char kDatabaseVersionKey[] = "INITDATA_DB_VERSION";
 const char kNextRegIdKey[] = "INITDATA_NEXT_REGISTRATION_ID";
 const char kNextResIdKey[] = "INITDATA_NEXT_RESOURCE_ID";
 const char kNextVerIdKey[] = "INITDATA_NEXT_VERSION_ID";
 const char kUniqueOriginKey[] = "INITDATA_UNIQUE_ORIGIN:";
+const char kDiskCacheMigrationNotNeededKey[] =
+    "INITDATA_DISKCACHE_MIGRATION_NOT_NEEDED";
+const char kOldDiskCacheDeletionNotNeededKey[] =
+    "INITDATA_OLD_DISKCACHE_DELETION_NOT_NEEDED";
 
 const char kRegKeyPrefix[] = "REG:";
 const char kRegUserDataKeyPrefix[] = "REG_USER_DATA:";
 const char kRegHasUserDataKeyPrefix[] = "REG_HAS_USER_DATA:";
 const char kRegIdToOriginKeyPrefix[] = "REGID_TO_ORIGIN:";
 const char kResKeyPrefix[] = "RES:";
 const char kKeySeparator = '\x00';
+const char kEmptyValue[] = "";
 
 const char kUncommittedResIdKeyPrefix[] = "URES:";
 const char kPurgeableResIdKeyPrefix[] = "PRES:";
 
 const int64 kCurrentSchemaVersion = 2;
 
 class ServiceWorkerEnv : public leveldb_env::ChromiumEnv {
  public:
   ServiceWorkerEnv()
       : ChromiumEnv("LevelDBEnv.ServiceWorker", false /* make_backup */) {}
@@ skipping 265 matching lines @@
 }
 
 ServiceWorkerDatabase::RegistrationData::~RegistrationData() {
 }
 
 ServiceWorkerDatabase::ServiceWorkerDatabase(const base::FilePath& path)
     : path_(path),
       next_avail_registration_id_(0),
       next_avail_resource_id_(0),
       next_avail_version_id_(0),
-      state_(UNINITIALIZED) {
+      state_(UNINITIALIZED),
+      skip_writing_diskcache_migration_state_on_init_(false) {
   sequence_checker_.DetachFromSequence();
 }
 
 ServiceWorkerDatabase::~ServiceWorkerDatabase() {
   DCHECK(sequence_checker_.CalledOnValidSequencedThread());
   db_.reset();
 }
 
 ServiceWorkerDatabase::Status ServiceWorkerDatabase::GetNextAvailableIds(
     int64* next_avail_registration_id,
@@ skipping 23 matching lines @@
   status = ReadNextAvailableId(kNextResIdKey, &next_avail_resource_id_);
   if (status != STATUS_OK)
     return status;
 
   *next_avail_registration_id = next_avail_registration_id_;
   *next_avail_version_id = next_avail_version_id_;
   *next_avail_resource_id = next_avail_resource_id_;
   return STATUS_OK;
 }
 
+ServiceWorkerDatabase::Status ServiceWorkerDatabase::IsDiskCacheMigrationNeeded(
+    bool* migration_needed) {
+  DCHECK(sequence_checker_.CalledOnValidSequencedThread());
+
+  Status status = LazyOpen(false);
+  if (IsNewOrNonexistentDatabase(status)) {
+    *migration_needed = false;
+    return STATUS_OK;
+  }
+  if (status != STATUS_OK)
+    return status;
+
+  std::string value;
+  status = LevelDBStatusToStatus(db_->Get(
+      leveldb::ReadOptions(), kDiskCacheMigrationNotNeededKey, &value));
+  if (status == STATUS_ERROR_NOT_FOUND) {
+    *migration_needed = true;
+    HandleReadResult(FROM_HERE, STATUS_OK);
+    return STATUS_OK;
+  }
+  if (status != STATUS_OK) {
+    HandleReadResult(FROM_HERE, status);
+    return status;
+  }
+
+  *migration_needed = false;
+  HandleReadResult(FROM_HERE, status);
+  return status;
+}
+
+ServiceWorkerDatabase::Status
+ServiceWorkerDatabase::SetDiskCacheMigrationNotNeeded() {
+  DCHECK(sequence_checker_.CalledOnValidSequencedThread());
+
+  Status status = LazyOpen(true);
+  if (status != STATUS_OK)
+    return status;
+
+  leveldb::WriteBatch batch;
+  batch.Put(kDiskCacheMigrationNotNeededKey, kEmptyValue);
+  return WriteBatch(&batch);
+}
+
+ServiceWorkerDatabase::Status
+ServiceWorkerDatabase::IsOldDiskCacheDeletionNeeded(bool* deletion_needed) {
+  DCHECK(sequence_checker_.CalledOnValidSequencedThread());
+
+  Status status = LazyOpen(false);
+  if (IsNewOrNonexistentDatabase(status)) {
+    *deletion_needed = false;
+    return STATUS_OK;
+  }
+  if (status != STATUS_OK)
+    return status;
+
+  std::string value;
+  status = LevelDBStatusToStatus(db_->Get(
+      leveldb::ReadOptions(), kOldDiskCacheDeletionNotNeededKey, &value));
+  if (status == STATUS_ERROR_NOT_FOUND) {
+    *deletion_needed = true;
+    HandleReadResult(FROM_HERE, STATUS_OK);
+    return STATUS_OK;
+  }
+  if (status != STATUS_OK) {
+    HandleReadResult(FROM_HERE, status);
+    return status;
+  }
+
+  *deletion_needed = false;
+  HandleReadResult(FROM_HERE, status);
+  return status;
+}
+
+ServiceWorkerDatabase::Status
+ServiceWorkerDatabase::SetOldDiskCacheDeletionNotNeeded() {
+  DCHECK(sequence_checker_.CalledOnValidSequencedThread());
+
+  Status status = LazyOpen(true);
+  if (status != STATUS_OK)
+    return status;
+
+  leveldb::WriteBatch batch;
+  batch.Put(kOldDiskCacheDeletionNotNeededKey, kEmptyValue);
+  return WriteBatch(&batch);
+}
+
 ServiceWorkerDatabase::Status
 ServiceWorkerDatabase::GetOriginsWithRegistrations(std::set<GURL>* origins) {
   DCHECK(sequence_checker_.CalledOnValidSequencedThread());
   DCHECK(origins->empty());
 
   Status status = LazyOpen(false);
   if (IsNewOrNonexistentDatabase(status))
     return STATUS_OK;
   if (status != STATUS_OK)
     return status;
@@ skipping 987 matching lines @@
   HandleReadResult(FROM_HERE, status);
   return status;
 }
 
 ServiceWorkerDatabase::Status ServiceWorkerDatabase::WriteBatch(
     leveldb::WriteBatch* batch) {
   DCHECK(batch);
   DCHECK_NE(DISABLED, state_);
 
   if (state_ == UNINITIALIZED) {
-    // Write the database schema version.
+    // Write database default values.
     batch->Put(kDatabaseVersionKey, base::Int64ToString(kCurrentSchemaVersion));
+    if (!skip_writing_diskcache_migration_state_on_init_) {
+      batch->Put(kDiskCacheMigrationNotNeededKey, kEmptyValue);
+      batch->Put(kOldDiskCacheDeletionNotNeededKey, kEmptyValue);
+    }
     state_ = INITIALIZED;
   }
 
   Status status = LevelDBStatusToStatus(
       db_->Write(leveldb::WriteOptions(), batch));
   HandleWriteResult(FROM_HERE, status);
   return status;
 }
 
 void ServiceWorkerDatabase::BumpNextRegistrationIdIfNeeded(
@@ skipping 57 matching lines @@
 
 void ServiceWorkerDatabase::HandleWriteResult(
     const tracked_objects::Location& from_here,
     Status status) {
   if (status != STATUS_OK)
     Disable(from_here, status);
   ServiceWorkerMetrics::CountWriteDatabaseResult(status);
 }
 
 }  // namespace content