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
|
/*
* Copyright (C) 2006 Apple Computer, Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "SQLiteTransaction.h"
#include "SQLiteDatabase.h"
namespace WebCore {
SQLiteTransaction::SQLiteTransaction(SQLiteDatabase& db, bool readOnly)
: m_db(db)
, m_inProgress(false)
, m_readOnly(readOnly)
{
}
SQLiteTransaction::~SQLiteTransaction()
{
if (m_inProgress)
rollback();
}
void SQLiteTransaction::begin()
{
if (!m_inProgress) {
ASSERT(!m_db.m_transactionInProgress);
// Call BEGIN IMMEDIATE for a write transaction to acquire
// a RESERVED lock on the DB file. Otherwise, another write
// transaction (on another connection) could make changes
// to the same DB file before this transaction gets to execute
// any statements. If that happens, this transaction will fail.
// http://www.sqlite.org/lang_transaction.html
// http://www.sqlite.org/lockingv3.html#locking
if (m_readOnly)
m_inProgress = m_db.executeCommand("BEGIN;");
else
m_inProgress = m_db.executeCommand("BEGIN IMMEDIATE;");
m_db.m_transactionInProgress = m_inProgress;
}
}
void SQLiteTransaction::commit()
{
// FIXME: this code is buggy; it assumes that COMMIT always succeeds which is not the case:
// the transaction could've been silently rolled back before getting to the COMMIT statement
// (https://bugs.webkit.org/show_bug.cgi?id=34280). However, the rest of the code does not
// know how to deal with a premature rollback and a failed COMMIT at this moment, so until
// we figure out what to do with bug 34280, it's better to leave this code as it is.
if (m_inProgress) {
ASSERT(m_db.m_transactionInProgress);
m_db.executeCommand("COMMIT;");
m_inProgress = false;
m_db.m_transactionInProgress = false;
}
}
void SQLiteTransaction::rollback()
{
if (m_inProgress) {
ASSERT(m_db.m_transactionInProgress);
m_db.executeCommand("ROLLBACK;");
m_inProgress = false;
m_db.m_transactionInProgress = false;
}
}
void SQLiteTransaction::stop()
{
if (m_inProgress) {
m_inProgress = false;
m_db.m_transactionInProgress = false;
}
}
} // namespace WebCore
|
