1/*
2 * Copyright (C) 2007, 2013 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * 1.  Redistributions of source code must retain the above copyright
9 *     notice, this list of conditions and the following disclaimer.
10 * 2.  Redistributions in binary form must reproduce the above copyright
11 *     notice, this list of conditions and the following disclaimer in the
12 *     documentation and/or other materials provided with the distribution.
13 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
14 *     its contributors may be used to endorse or promote products derived
15 *     from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28#ifndef SQLTransactionBackend_h
29#define SQLTransactionBackend_h
30
31#include "modules/webdatabase/AbstractSQLStatement.h"
32#include "modules/webdatabase/AbstractSQLTransactionBackend.h"
33#include "modules/webdatabase/DatabaseBasicTypes.h"
34#include "modules/webdatabase/SQLTransactionStateMachine.h"
35#include "wtf/Deque.h"
36#include "wtf/Forward.h"
37#include "wtf/ThreadingPrimitives.h"
38#include "wtf/text/WTFString.h"
39
40namespace WebCore {
41
42class AbstractSQLTransaction;
43class DatabaseBackend;
44class SQLError;
45class SQLiteTransaction;
46class SQLStatementBackend;
47class SQLTransactionBackend;
48class SQLValue;
49
50class SQLTransactionWrapper : public ThreadSafeRefCounted<SQLTransactionWrapper> {
51public:
52    virtual ~SQLTransactionWrapper() { }
53    virtual bool performPreflight(SQLTransactionBackend*) = 0;
54    virtual bool performPostflight(SQLTransactionBackend*) = 0;
55    virtual SQLError* sqlError() const = 0;
56    virtual void handleCommitFailedAfterPostflight(SQLTransactionBackend*) = 0;
57};
58
59class SQLTransactionBackend : public SQLTransactionStateMachine<SQLTransactionBackend>, public AbstractSQLTransactionBackend {
60public:
61    static PassRefPtr<SQLTransactionBackend> create(DatabaseBackend*,
62        PassRefPtr<AbstractSQLTransaction>, PassRefPtr<SQLTransactionWrapper>, bool readOnly);
63
64    virtual ~SQLTransactionBackend();
65
66    void lockAcquired();
67    void performNextStep();
68
69    DatabaseBackend* database() { return m_database.get(); }
70    bool isReadOnly() { return m_readOnly; }
71    void notifyDatabaseThreadIsShuttingDown();
72
73private:
74    SQLTransactionBackend(DatabaseBackend*, PassRefPtr<AbstractSQLTransaction>,
75        PassRefPtr<SQLTransactionWrapper>, bool readOnly);
76
77    // APIs called from the frontend published via AbstractSQLTransactionBackend:
78    virtual void requestTransitToState(SQLTransactionState) OVERRIDE;
79    virtual PassRefPtr<SQLError> transactionError() OVERRIDE;
80    virtual AbstractSQLStatement* currentStatement() OVERRIDE;
81    virtual void setShouldRetryCurrentStatement(bool) OVERRIDE;
82    virtual void executeSQL(PassOwnPtr<AbstractSQLStatement>, const String& statement,
83        const Vector<SQLValue>& arguments, int permissions) OVERRIDE;
84
85    void doCleanup();
86
87    void enqueueStatementBackend(PassRefPtr<SQLStatementBackend>);
88
89    // State Machine functions:
90    virtual StateFunction stateFunctionFor(SQLTransactionState) OVERRIDE;
91    void computeNextStateAndCleanupIfNeeded();
92
93    // State functions:
94    SQLTransactionState acquireLock();
95    SQLTransactionState openTransactionAndPreflight();
96    SQLTransactionState runStatements();
97    SQLTransactionState postflightAndCommit();
98    SQLTransactionState cleanupAndTerminate();
99    SQLTransactionState cleanupAfterTransactionErrorCallback();
100
101    SQLTransactionState unreachableState();
102    SQLTransactionState sendToFrontendState();
103
104    SQLTransactionState nextStateForCurrentStatementError();
105    SQLTransactionState nextStateForTransactionError();
106    SQLTransactionState runCurrentStatementAndGetNextState();
107
108    void getNextStatement();
109
110    RefPtr<AbstractSQLTransaction> m_frontend; // Has a reference cycle, and will break in doCleanup().
111    RefPtr<SQLStatementBackend> m_currentStatementBackend;
112
113    RefPtr<DatabaseBackend> m_database;
114    RefPtr<SQLTransactionWrapper> m_wrapper;
115    RefPtr<SQLError> m_transactionError;
116
117    bool m_hasCallback;
118    bool m_hasSuccessCallback;
119    bool m_hasErrorCallback;
120    bool m_shouldRetryCurrentStatement;
121    bool m_modifiedDatabase;
122    bool m_lockAcquired;
123    bool m_readOnly;
124    bool m_hasVersionMismatch;
125
126    Mutex m_statementMutex;
127    Deque<RefPtr<SQLStatementBackend> > m_statementQueue;
128
129    OwnPtr<SQLiteTransaction> m_sqliteTransaction;
130};
131
132} // namespace WebCore
133
134#endif // SQLTransactionBackend_h
135