blob: b05094ba421b2997c51f5d5ed195a0bba818dd3d [file] [log] [blame]
// Copyright (c) 2012 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 <utility>
#include "base/files/file_path.h"
#include "base/macros.h"
#include "base/metrics/field_trial.h"
#include "base/single_thread_task_runner.h"
#include "base/task/task_scheduler/task_scheduler.h"
#include "net/base/cache_type.h"
#include "net/base/net_errors.h"
#include "net/disk_cache/backend_cleanup_tracker.h"
#include "net/disk_cache/blockfile/backend_impl.h"
#include "net/disk_cache/cache_util.h"
#include "net/disk_cache/disk_cache.h"
#include "net/disk_cache/memory/mem_backend_impl.h"
#include "net/disk_cache/simple/simple_backend_impl.h"
namespace {
// Builds an instance of the backend depending on platform, type, experiments
// etc. Takes care of the retry state. This object will self-destroy when
// finished.
class CacheCreator {
public:
CacheCreator(const base::FilePath& path,
bool force,
int max_bytes,
net::CacheType type,
net::BackendType backend_type,
uint32_t flags,
net::NetLog* net_log,
std::unique_ptr<disk_cache::Backend>* backend,
base::OnceClosure post_cleanup_callback,
net::CompletionOnceCallback callback);
int TryCreateCleanupTrackerAndRun();
// Creates the backend, the cleanup context for it having been already
// established... or purposefully left as null.
int Run();
private:
~CacheCreator();
void DoCallback(int result);
void OnIOComplete(int result);
const base::FilePath path_;
bool force_;
bool retry_;
int max_bytes_;
net::CacheType type_;
net::BackendType backend_type_;
#if !defined(OS_ANDROID)
uint32_t flags_;
#endif
std::unique_ptr<disk_cache::Backend>* backend_;
base::OnceClosure post_cleanup_callback_;
net::CompletionOnceCallback callback_;
std::unique_ptr<disk_cache::Backend> created_cache_;
net::NetLog* net_log_;
scoped_refptr<disk_cache::BackendCleanupTracker> cleanup_tracker_;
DISALLOW_COPY_AND_ASSIGN(CacheCreator);
};
CacheCreator::CacheCreator(const base::FilePath& path,
bool force,
int max_bytes,
net::CacheType type,
net::BackendType backend_type,
uint32_t flags,
net::NetLog* net_log,
std::unique_ptr<disk_cache::Backend>* backend,
base::OnceClosure post_cleanup_callback,
net::CompletionOnceCallback callback)
: path_(path),
force_(force),
retry_(false),
max_bytes_(max_bytes),
type_(type),
backend_type_(backend_type),
#if !defined(OS_ANDROID)
flags_(flags),
#endif
backend_(backend),
post_cleanup_callback_(std::move(post_cleanup_callback)),
callback_(std::move(callback)),
net_log_(net_log) {
}
CacheCreator::~CacheCreator() = default;
int CacheCreator::Run() {
#if defined(OS_ANDROID)
static const bool kSimpleBackendIsDefault = true;
#else
static const bool kSimpleBackendIsDefault = false;
#endif
if (backend_type_ == net::CACHE_BACKEND_SIMPLE ||
(backend_type_ == net::CACHE_BACKEND_DEFAULT &&
kSimpleBackendIsDefault)) {
disk_cache::SimpleBackendImpl* simple_cache =
new disk_cache::SimpleBackendImpl(path_, cleanup_tracker_.get(),
/* file_tracker = */ nullptr,
max_bytes_, type_, net_log_);
created_cache_.reset(simple_cache);
return simple_cache->Init(
base::Bind(&CacheCreator::OnIOComplete, base::Unretained(this)));
}
// Avoid references to blockfile functions on Android to reduce binary size.
#if defined(OS_ANDROID)
return net::ERR_FAILED;
#else
disk_cache::BackendImpl* new_cache = new disk_cache::BackendImpl(
path_, cleanup_tracker_.get(), /*cache_thread = */ nullptr, net_log_);
created_cache_.reset(new_cache);
new_cache->SetMaxSize(max_bytes_);
new_cache->SetType(type_);
new_cache->SetFlags(flags_);
int rv = new_cache->Init(
base::Bind(&CacheCreator::OnIOComplete, base::Unretained(this)));
DCHECK_EQ(net::ERR_IO_PENDING, rv);
return rv;
#endif
}
int CacheCreator::TryCreateCleanupTrackerAndRun() {
// Before creating a cache Backend, a BackendCleanupTracker object is needed
// so there is a place to keep track of outstanding I/O even after the backend
// object itself is destroyed, so that further use of the directory
// doesn't race with those outstanding disk I/O ops.
// This method's purpose it to grab exlusive ownership of a fresh
// BackendCleanupTracker for the cache path, and then move on to Run(),
// which will take care of creating the actual cache backend. It's possible
// that something else is currently making use of the directory, in which
// case BackendCleanupTracker::TryCreate will fail, but will just have
// TryCreateCleanupTrackerAndRun run again at an opportune time to make
// another attempt.
// The resulting BackendCleanupTracker is stored into a scoped_refptr member
// so that it's kept alive while |this| CacheCreator exists , so that in the
// case Run() needs to retry Backend creation the same BackendCleanupTracker
// is used for both attempts, and |post_cleanup_callback_| gets called after
// the second try, not the first one.
cleanup_tracker_ = disk_cache::BackendCleanupTracker::TryCreate(
path_, base::BindOnce(base::IgnoreResult(
&CacheCreator::TryCreateCleanupTrackerAndRun),
base::Unretained(this)));
if (!cleanup_tracker_)
return net::ERR_IO_PENDING;
if (!post_cleanup_callback_.is_null())
cleanup_tracker_->AddPostCleanupCallback(std::move(post_cleanup_callback_));
return Run();
}
void CacheCreator::DoCallback(int result) {
DCHECK_NE(net::ERR_IO_PENDING, result);
if (result == net::OK) {
*backend_ = std::move(created_cache_);
} else {
LOG(ERROR) << "Unable to create cache";
created_cache_.reset();
}
std::move(callback_).Run(result);
delete this;
}
// If the initialization of the cache fails, and |force| is true, we will
// discard the whole cache and create a new one.
void CacheCreator::OnIOComplete(int result) {
if (result == net::OK || !force_ || retry_)
return DoCallback(result);
// This is a failure and we are supposed to try again, so delete the object,
// delete all the files, and try again.
retry_ = true;
created_cache_.reset();
if (!disk_cache::DelayedCacheCleanup(path_))
return DoCallback(result);
// The worker thread will start deleting files soon, but the original folder
// is not there anymore... let's create a new set of files.
int rv = Run();
DCHECK_EQ(net::ERR_IO_PENDING, rv);
}
} // namespace
namespace disk_cache {
int CreateCacheBackendImpl(net::CacheType type,
net::BackendType backend_type,
const base::FilePath& path,
int max_bytes,
bool force,
net::NetLog* net_log,
std::unique_ptr<Backend>* backend,
base::OnceClosure post_cleanup_callback,
net::CompletionOnceCallback callback) {
DCHECK(!callback.is_null());
if (type == net::MEMORY_CACHE) {
std::unique_ptr<MemBackendImpl> mem_backend_impl =
disk_cache::MemBackendImpl::CreateBackend(max_bytes, net_log);
if (mem_backend_impl) {
mem_backend_impl->SetPostCleanupCallback(
std::move(post_cleanup_callback));
*backend = std::move(mem_backend_impl);
return net::OK;
} else {
if (!post_cleanup_callback.is_null())
base::SequencedTaskRunnerHandle::Get()->PostTask(
FROM_HERE, std::move(post_cleanup_callback));
return net::ERR_FAILED;
}
}
bool had_post_cleanup_callback = !post_cleanup_callback.is_null();
CacheCreator* creator = new CacheCreator(
path, force, max_bytes, type, backend_type, kNone, net_log, backend,
std::move(post_cleanup_callback), std::move(callback));
if (type == net::DISK_CACHE || type == net::MEDIA_CACHE) {
DCHECK(!had_post_cleanup_callback);
return creator->Run();
}
return creator->TryCreateCleanupTrackerAndRun();
}
int CreateCacheBackend(net::CacheType type,
net::BackendType backend_type,
const base::FilePath& path,
int max_bytes,
bool force,
net::NetLog* net_log,
std::unique_ptr<Backend>* backend,
net::CompletionOnceCallback callback) {
return CreateCacheBackendImpl(type, backend_type, path, max_bytes, force,
net_log, backend, base::OnceClosure(),
std::move(callback));
}
int CreateCacheBackend(net::CacheType type,
net::BackendType backend_type,
const base::FilePath& path,
int max_bytes,
bool force,
net::NetLog* net_log,
std::unique_ptr<Backend>* backend,
base::OnceClosure post_cleanup_callback,
net::CompletionOnceCallback callback) {
return CreateCacheBackendImpl(
type, backend_type, path, max_bytes, force, net_log, backend,
std::move(post_cleanup_callback), std::move(callback));
}
void FlushCacheThreadForTesting() {
// For simple backend.
SimpleBackendImpl::FlushWorkerPoolForTesting();
base::TaskScheduler::GetInstance()->FlushForTesting();
// Block backend.
BackendImpl::FlushForTesting();
}
int Backend::CalculateSizeOfEntriesBetween(base::Time initial_time,
base::Time end_time,
CompletionOnceCallback callback) {
return net::ERR_NOT_IMPLEMENTED;
}
uint8_t Backend::GetEntryInMemoryData(const std::string& key) {
return 0;
}
void Backend::SetEntryInMemoryData(const std::string& key, uint8_t data) {}
} // namespace disk_cache