1 | /* cache.h - definitions for the LRU cache |
2 | * |
3 | * Copyright (C) 2004-2010 Gerhard Häring <[email protected]> |
4 | * |
5 | * This file is part of pysqlite. |
6 | * |
7 | * This software is provided 'as-is', without any express or implied |
8 | * warranty. In no event will the authors be held liable for any damages |
9 | * arising from the use of this software. |
10 | * |
11 | * Permission is granted to anyone to use this software for any purpose, |
12 | * including commercial applications, and to alter it and redistribute it |
13 | * freely, subject to the following restrictions: |
14 | * |
15 | * 1. The origin of this software must not be misrepresented; you must not |
16 | * claim that you wrote the original software. If you use this software |
17 | * in a product, an acknowledgment in the product documentation would be |
18 | * appreciated but is not required. |
19 | * 2. Altered source versions must be plainly marked as such, and must not be |
20 | * misrepresented as being the original software. |
21 | * 3. This notice may not be removed or altered from any source distribution. |
22 | */ |
23 | |
24 | #ifndef PYSQLITE_CACHE_H |
25 | #define PYSQLITE_CACHE_H |
26 | #include "module.h" |
27 | |
28 | /* The LRU cache is implemented as a combination of a doubly-linked with a |
29 | * dictionary. The list items are of type 'Node' and the dictionary has the |
30 | * nodes as values. */ |
31 | |
32 | typedef struct _pysqlite_Node |
33 | { |
34 | PyObject_HEAD |
35 | PyObject* key; |
36 | PyObject* data; |
37 | long count; |
38 | struct _pysqlite_Node* prev; |
39 | struct _pysqlite_Node* next; |
40 | } pysqlite_Node; |
41 | |
42 | typedef struct |
43 | { |
44 | PyObject_HEAD |
45 | int size; |
46 | |
47 | /* a dictionary mapping keys to Node entries */ |
48 | PyObject* mapping; |
49 | |
50 | /* the factory callable */ |
51 | PyObject* factory; |
52 | |
53 | pysqlite_Node* first; |
54 | pysqlite_Node* last; |
55 | |
56 | /* if set, decrement the factory function when the Cache is deallocated. |
57 | * this is almost always desirable, but not in the pysqlite context */ |
58 | int decref_factory; |
59 | } pysqlite_Cache; |
60 | |
61 | extern PyTypeObject *pysqlite_NodeType; |
62 | extern PyTypeObject *pysqlite_CacheType; |
63 | |
64 | PyObject* pysqlite_cache_get(pysqlite_Cache* self, PyObject* args); |
65 | |
66 | int pysqlite_cache_setup_types(PyObject *module); |
67 | |
68 | #endif |
69 | |