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
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
|
// file : odb/cache-traits.hxx
// copyright : Copyright (c) 2009-2012 Code Synthesis Tools CC
// license : GNU GPL v2; see accompanying LICENSE file
#ifndef ODB_CACHE_TRAITS_HXX
#define ODB_CACHE_TRAITS_HXX
#include <odb/pre.hxx>
#include <odb/traits.hxx>
#include <odb/forward.hxx>
#include <odb/session.hxx>
#include <odb/pointer-traits.hxx>
#include <odb/no-op-cache-traits.hxx>
namespace odb
{
// pointer_cache_traits
//
// Caching traits for objects passed by pointer. P should be the canonical
// pointer (non-const).
//
template <typename P, typename S, pointer_kind pk>
struct pointer_cache_traits_impl
{
typedef P pointer_type;
typedef S session_type;
typedef odb::pointer_traits<pointer_type> pointer_traits;
typedef typename pointer_traits::element_type object_type;
typedef typename object_traits<object_type>::id_type id_type;
typedef typename session_type::template position<object_type> position_type;
struct insert_guard
{
insert_guard () {}
insert_guard (const position_type& pos): pos_ (pos) {}
~insert_guard () {session_type::erase (pos_);}
const position_type&
position () const {return pos_;}
void
release () {pos_ = position_type ();}
// Note: doesn't call erase() on the old position (assumes empty).
//
void
reset (const position_type& pos) {pos_ = pos;}
private:
position_type pos_;
};
// Cache management.
//
// We need the insert() overload with explicit id to handle self-
// references. In such cases the object is not yet loaded and the
// id member does not contain the correct id.
//
// Qualify the database type to resolve a phony ambiguity in VC 10.
//
static position_type
insert (odb::database& db, const id_type& id, const pointer_type& p)
{
return session_type::template insert<object_type> (db, id, p);
}
static position_type
insert (odb::database& db, const pointer_type& p)
{
const id_type& id (
object_traits<object_type>::id (
pointer_traits::get_ref (p)));
return session_type::template insert<object_type> (db, id, p);
}
static pointer_type
find (odb::database& db, const id_type& id)
{
return session_type::template find<object_type> (db, id);
}
static void
erase (const position_type& p)
{
session_type::template erase<object_type> (p);
}
// Notifications.
//
static void
persist (const position_type& p)
{
session_type::template persist<object_type> (p);
}
static void
load (const position_type& p)
{
session_type::template load<object_type> (p);
}
static void
update (odb::database& db, const object_type& obj)
{
session_type::template update<object_type> (db, obj);
}
static void
erase (odb::database& db, const id_type& id)
{
session_type::template erase<object_type> (db, id);
}
};
// Unique pointers don't work with the object cache.
//
template <typename P, typename S>
struct pointer_cache_traits_impl<P, S, pk_unique>:
no_op_pointer_cache_traits<P> {};
template <typename P, typename S>
struct pointer_cache_traits:
pointer_cache_traits_impl<P, S, pointer_traits<P>::kind> {};
// reference_cache_traits
//
// Caching traits for objects passed by reference. T should be the
// canonical object type (non-const). Only if the object pointer
// kind is raw do we add the object to the session.
//
template <typename T, typename S, pointer_kind pk>
struct reference_cache_traits_impl: no_op_reference_cache_traits<T> {};
template <typename T, typename S>
struct reference_cache_traits_impl<T, S, pk_raw>
{
typedef T object_type;
typedef typename object_traits<object_type>::pointer_type pointer_type;
typedef typename object_traits<object_type>::id_type id_type;
typedef pointer_cache_traits<pointer_type, S> pointer_traits;
typedef typename pointer_traits::position_type position_type;
typedef typename pointer_traits::insert_guard insert_guard;
static position_type
insert (odb::database& db, const id_type& id, object_type& obj)
{
pointer_type p (&obj);
return pointer_traits::insert (db, id, p);
}
static position_type
insert (odb::database& db, object_type& obj)
{
pointer_type p (&obj);
return pointer_traits::insert (db, p);
}
static void
persist (const position_type& p)
{
pointer_traits::persist (p);
}
static void
load (const position_type& p)
{
pointer_traits::load (p);
}
};
template <typename T, typename S>
struct reference_cache_traits:
reference_cache_traits_impl<
T, S, pointer_traits<typename object_traits<T>::pointer_type>::kind> {};
}
#include <odb/post.hxx>
#endif // ODB_CACHE_TRAITS_HXX
|
