1// Copyright 2011 The Kyua Authors.
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28
29#include "utils/sqlite/transaction.hpp"
30
31#include "utils/format/macros.hpp"
32#include "utils/logging/macros.hpp"
33#include "utils/noncopyable.hpp"
34#include "utils/sanity.hpp"
35#include "utils/sqlite/database.hpp"
36#include "utils/sqlite/exceptions.hpp"
37#include "utils/sqlite/statement.ipp"
38
39namespace sqlite = utils::sqlite;
40
41
42/// Internal implementation for the transaction.
43struct utils::sqlite::transaction::impl : utils::noncopyable {
44    /// The database this transaction belongs to.
45    database& db;
46
47    /// Possible statuses of a transaction.
48    enum statuses {
49        open_status,
50        committed_status,
51        rolled_back_status,
52    };
53
54    /// The current status of the transaction.
55    statuses status;
56
57    /// Constructs a new transaction.
58    ///
59    /// \param db_ The database this transaction belongs to.
60    /// \param status_ The status of the new transaction.
61    impl(database& db_, const statuses status_) :
62        db(db_),
63        status(status_)
64    {
65    }
66
67    /// Destroys the transaction.
68    ///
69    /// This rolls back the transaction if it is open.
70    ~impl(void)
71    {
72        if (status == impl::open_status) {
73            try {
74                rollback();
75            } catch (const sqlite::error& e) {
76                LW(F("Error while rolling back a transaction: %s") % e.what());
77            }
78        }
79    }
80
81    /// Commits the transaction.
82    ///
83    /// \throw api_error If there is any problem while committing the
84    ///     transaction.
85    void
86    commit(void)
87    {
88        PRE(status == impl::open_status);
89        db.exec("COMMIT");
90        status = impl::committed_status;
91    }
92
93    /// Rolls the transaction back.
94    ///
95    /// \throw api_error If there is any problem while rolling the
96    ///     transaction back.
97    void
98    rollback(void)
99    {
100        PRE(status == impl::open_status);
101        db.exec("ROLLBACK");
102        status = impl::rolled_back_status;
103    }
104};
105
106
107/// Initializes a transaction object.
108///
109/// This is an internal function.  Use database::begin_transaction() to
110/// instantiate one of these objects.
111///
112/// \param db The database this transaction belongs to.
113sqlite::transaction::transaction(database& db) :
114    _pimpl(new impl(db, impl::open_status))
115{
116}
117
118
119/// Destructor for the transaction.
120sqlite::transaction::~transaction(void)
121{
122}
123
124
125/// Commits the transaction.
126///
127/// \throw api_error If there is any problem while committing the transaction.
128void
129sqlite::transaction::commit(void)
130{
131    _pimpl->commit();
132}
133
134
135/// Rolls the transaction back.
136///
137/// \throw api_error If there is any problem while rolling the transaction back.
138void
139sqlite::transaction::rollback(void)
140{
141    _pimpl->rollback();
142}
143