1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
|
// 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 "chrome/browser/sync/glue/history_model_worker.h"
#include "base/memory/ref_counted.h"
#include "base/message_loop/message_loop.h"
#include "base/synchronization/waitable_event.h"
#include "content/public/browser/browser_thread.h"
using base::WaitableEvent;
using content::BrowserThread;
namespace browser_sync {
class WorkerTask : public history::HistoryDBTask {
public:
WorkerTask(
const syncer::WorkCallback& work,
WaitableEvent* done,
syncer::SyncerError* error)
: work_(work), done_(done), error_(error) {}
virtual bool RunOnDBThread(history::HistoryBackend* backend,
history::HistoryDatabase* db) OVERRIDE {
*error_ = work_.Run();
done_->Signal();
return true;
}
// Since the DoWorkAndWaitUntilDone() is synchronous, we don't need to run
// any code asynchronously on the main thread after completion.
virtual void DoneRunOnMainThread() OVERRIDE {}
protected:
virtual ~WorkerTask() {}
syncer::WorkCallback work_;
WaitableEvent* done_;
syncer::SyncerError* error_;
};
class AddDBThreadObserverTask : public history::HistoryDBTask {
public:
explicit AddDBThreadObserverTask(base::Closure register_callback)
: register_callback_(register_callback) {}
virtual bool RunOnDBThread(history::HistoryBackend* backend,
history::HistoryDatabase* db) OVERRIDE {
register_callback_.Run();
return true;
}
virtual void DoneRunOnMainThread() OVERRIDE {}
private:
virtual ~AddDBThreadObserverTask() {}
base::Closure register_callback_;
};
namespace {
// Post the work task on |history_service|'s DB thread from the UI
// thread.
void PostWorkerTask(const base::WeakPtr<HistoryService>& history_service,
const syncer::WorkCallback& work,
base::CancelableTaskTracker* cancelable_tracker,
WaitableEvent* done,
syncer::SyncerError* error) {
DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
if (history_service.get()) {
scoped_ptr<history::HistoryDBTask> task(new WorkerTask(work, done, error));
history_service->ScheduleDBTask(task.Pass(), cancelable_tracker);
} else {
*error = syncer::CANNOT_DO_WORK;
done->Signal();
}
}
} // namespace
HistoryModelWorker::HistoryModelWorker(
const base::WeakPtr<HistoryService>& history_service,
syncer::WorkerLoopDestructionObserver* observer)
: syncer::ModelSafeWorker(observer),
history_service_(history_service) {
CHECK(history_service.get());
CHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
cancelable_tracker_.reset(new base::CancelableTaskTracker);
}
void HistoryModelWorker::RegisterForLoopDestruction() {
CHECK(history_service_.get());
history_service_->ScheduleDBTask(
scoped_ptr<history::HistoryDBTask>(new AddDBThreadObserverTask(
base::Bind(&HistoryModelWorker::RegisterOnDBThread, this))),
cancelable_tracker_.get());
}
void HistoryModelWorker::RegisterOnDBThread() {
SetWorkingLoopToCurrent();
}
syncer::SyncerError HistoryModelWorker::DoWorkAndWaitUntilDoneImpl(
const syncer::WorkCallback& work) {
syncer::SyncerError error = syncer::UNSET;
if (BrowserThread::PostTask(BrowserThread::UI,
FROM_HERE,
base::Bind(&PostWorkerTask,
history_service_,
work,
cancelable_tracker_.get(),
work_done_or_stopped(),
&error))) {
work_done_or_stopped()->Wait();
} else {
error = syncer::CANNOT_DO_WORK;
}
return error;
}
syncer::ModelSafeGroup HistoryModelWorker::GetModelSafeGroup() {
return syncer::GROUP_HISTORY;
}
HistoryModelWorker::~HistoryModelWorker() {
// The base::CancelableTaskTracker class is not thread-safe and must only be
// used from a single thread but the current object may not be destroyed from
// the UI thread, so delete it from the UI thread.
BrowserThread::DeleteOnUIThread::Destruct(cancelable_tracker_.release());
}
} // namespace browser_sync
|
