summaryrefslogtreecommitdiffstats
path: root/contrib/tools/python3/src/Modules/_sqlite/cache.h
blob: b1988c30c3fa754c144aca373deaf0340d3e2660 (plain) (blame)
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
/* cache.h - definitions for the LRU cache 
 * 
 * Copyright (C) 2004-2010 Gerhard Häring <[email protected]> 
 * 
 * This file is part of pysqlite. 
 * 
 * This software is provided 'as-is', without any express or implied 
 * warranty.  In no event will the authors be held liable for any damages 
 * arising from the use of this software. 
 * 
 * Permission is granted to anyone to use this software for any purpose, 
 * including commercial applications, and to alter it and redistribute it 
 * freely, subject to the following restrictions: 
 * 
 * 1. The origin of this software must not be misrepresented; you must not 
 *    claim that you wrote the original software. If you use this software 
 *    in a product, an acknowledgment in the product documentation would be 
 *    appreciated but is not required. 
 * 2. Altered source versions must be plainly marked as such, and must not be 
 *    misrepresented as being the original software. 
 * 3. This notice may not be removed or altered from any source distribution. 
 */ 
 
#ifndef PYSQLITE_CACHE_H 
#define PYSQLITE_CACHE_H 
#define PY_SSIZE_T_CLEAN
#include "Python.h" 
 
/* The LRU cache is implemented as a combination of a doubly-linked with a 
 * dictionary. The list items are of type 'Node' and the dictionary has the 
 * nodes as values. */ 
 
typedef struct _pysqlite_Node 
{ 
    PyObject_HEAD 
    PyObject* key; 
    PyObject* data; 
    long count; 
    struct _pysqlite_Node* prev; 
    struct _pysqlite_Node* next; 
} pysqlite_Node; 
 
typedef struct 
{ 
    PyObject_HEAD 
    int size; 
 
    /* a dictionary mapping keys to Node entries */ 
    PyObject* mapping; 
 
    /* the factory callable */ 
    PyObject* factory; 
 
    pysqlite_Node* first; 
    pysqlite_Node* last; 
 
    /* if set, decrement the factory function when the Cache is deallocated. 
     * this is almost always desirable, but not in the pysqlite context */ 
    int decref_factory; 
} pysqlite_Cache; 
 
extern PyTypeObject pysqlite_NodeType; 
extern PyTypeObject pysqlite_CacheType; 
 
int pysqlite_node_init(pysqlite_Node* self, PyObject* args, PyObject* kwargs); 
void pysqlite_node_dealloc(pysqlite_Node* self); 
 
int pysqlite_cache_init(pysqlite_Cache* self, PyObject* args, PyObject* kwargs); 
void pysqlite_cache_dealloc(pysqlite_Cache* self); 
PyObject* pysqlite_cache_get(pysqlite_Cache* self, PyObject* args); 
 
int pysqlite_cache_setup_types(void); 
 
#endif