summaryrefslogtreecommitdiffstats
path: root/lib/libUPnP/Platinum/Source/Devices/MediaServer/PltMediaCache.h
blob: 8e365d807e1394a4034de2f1f0e4a800ee36fdb4 (plain)
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
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
/*****************************************************************
|
|   Platinum - AV Media Cache
|
| Copyright (c) 2004-2010, Plutinosoft, LLC.
| All rights reserved.
| http://www.plutinosoft.com
|
| This program is free software; you can redistribute it and/or
| modify it under the terms of the GNU General Public License
| as published by the Free Software Foundation; either version 2
| of the License, or (at your option) any later version.
|
| OEMs, ISVs, VARs and other distributors that combine and 
| distribute commercially licensed software with Platinum software
| and do not wish to distribute the source code for the commercially
| licensed software under version 2, or (at your option) any later
| version, of the GNU General Public License (the "GPL") must enter
| into a commercial license agreement with Plutinosoft, LLC.
| licensing@plutinosoft.com
|  
| This program is distributed in the hope that it will be useful,
| but WITHOUT ANY WARRANTY; without even the implied warranty of
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
| GNU General Public License for more details.
|
| You should have received a copy of the GNU General Public License
| along with this program; see the file LICENSE.txt. If not, write to
| the Free Software Foundation, Inc., 
| 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
| http://www.gnu.org/licenses/gpl-2.0.html
|
****************************************************************/

/** @file
 Simple Object Caching utility.
 */

#ifndef _PLT_MEDIA_CACHE_H_
#define _PLT_MEDIA_CACHE_H_

/*----------------------------------------------------------------------
|   includes
+---------------------------------------------------------------------*/
#include "Neptune.h"

/*----------------------------------------------------------------------
|   PLT_MediaCache
+---------------------------------------------------------------------*/
/**
 The PLT_MediaCache template provides a way to hold references to object in 
 memory. 
 */ 
template <typename T, typename U>
class PLT_MediaCache
{
public:
    typedef typename NPT_Map<NPT_String,T>::Entry ElementEntry;
    typedef typename NPT_List<ElementEntry*>::Iterator ElementIterator;

    PLT_MediaCache<T,U>() {}
    virtual ~PLT_MediaCache<T,U>() {}

    NPT_Result Put(const char* root, const char* key, T& value, U* tag = NULL);
    NPT_Result Get(const char* root, const char* key, T& value, U* tag = NULL);
    NPT_Result Clear(const char* root, const char* key);
    NPT_Result Clear(const char* root = NULL);

private:
    // methods
    NPT_String GenerateKey(const char* root, const char* key);

private:
    // members
    NPT_Mutex              m_Mutex;
    NPT_Map<NPT_String, T> m_Items;
    NPT_Map<NPT_String, U> m_Tags;
};

/*----------------------------------------------------------------------
|   PLT_MediaCache::GenerateKey
+---------------------------------------------------------------------*/
template <typename T, typename U>
inline
NPT_String
PLT_MediaCache<T,U>::GenerateKey(const char* root, const char* key)
{
    // TODO: There could be collision
    NPT_String result = root;
    result += "/";
    result += key;
    return result;
}

/*----------------------------------------------------------------------
|   PLT_MediaCache::Put
+---------------------------------------------------------------------*/
template <typename T, typename U>
inline
NPT_Result
PLT_MediaCache<T,U>::Put(const char* root,
                         const char* key, 
                         T&          value,
                         U*          tag)
{
    NPT_AutoLock lock(m_Mutex);

    NPT_String fullkey = GenerateKey(root, key);
    if (fullkey.GetLength() == 0) return NPT_ERROR_INVALID_PARAMETERS;

    m_Items.Erase(fullkey);
    NPT_CHECK(m_Items.Put(fullkey, value));
    
    if (tag) NPT_CHECK(m_Tags.Put(fullkey, *tag));
    
    return NPT_SUCCESS;
}

/*----------------------------------------------------------------------
|   PLT_MediaCache::Get
+---------------------------------------------------------------------*/
template <typename T, typename U>
inline
NPT_Result
PLT_MediaCache<T,U>::Get(const char* root,
                         const char* key,
                         T&          value,
                         U*          tag /* = NULL */)
{
    NPT_AutoLock lock(m_Mutex);

    NPT_String fullkey = GenerateKey(root, key);
    if (fullkey.GetLength() == 0) return NPT_ERROR_INVALID_PARAMETERS;
    
    T* _value = NULL;
    NPT_CHECK(m_Items.Get(fullkey, _value));
    
    U* _tag;
    if (tag) {
        m_Tags.Get(fullkey, _tag);
        if (_tag) *tag = *_tag;
    }

    value = *_value;
    return NPT_SUCCESS;
}

/*----------------------------------------------------------------------
|   PLT_MediaCache::Clear
+---------------------------------------------------------------------*/
template <typename T, typename U>
inline
NPT_Result 
PLT_MediaCache<T,U>::Clear(const char* root, const char* key) 
{
    NPT_AutoLock lock(m_Mutex);

    NPT_String fullkey = GenerateKey(root, key);
    if (fullkey.GetLength() == 0) return NPT_ERROR_INVALID_PARAMETERS;

    ElementIterator entries = m_Items.GetEntries().GetFirstItem();
    ElementIterator entry;
    while (entries) {
        entry = entries++;
        if ((*entry)->GetKey() == (fullkey)) {
            m_Items.Erase(fullkey);
            m_Tags.Erase(fullkey);
            return NPT_SUCCESS;
        }
    }

    return NPT_ERROR_NO_SUCH_ITEM;
}

/*----------------------------------------------------------------------
|   PLT_MediaCache::Clear
+---------------------------------------------------------------------*/
template <typename T, typename U>
inline
NPT_Result
PLT_MediaCache<T,U>::Clear(const char* root)
{
    NPT_AutoLock lock(m_Mutex);

    if (!root || root[0]=='\0') 
        return m_Items.Clear();

    NPT_String key = GenerateKey(root, "");
    ElementIterator entries = m_Items.GetEntries().GetFirstItem();
    ElementIterator entry;
    while (entries) {
        entry = entries++;
        NPT_String entry_key = (*entry)->GetKey();
        if (entry_key.StartsWith(key)) {
            m_Items.Erase(entry_key);
            m_Tags.Erase(entry_key);
        }
    }

    return NPT_SUCCESS;
}

#endif /* _PLT_MEDIA_CACHE_H_ */