QGIS API Documentation 3.43.0-Master (6c62b930b02)
qgsnetworkdiskcache.cpp
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1/***************************************************************************
2 qgsnetworkdiskcache.cpp - Thread-safe interface for QNetworkDiskCache
3 -------------------
4 begin : 2016-03-05
5 copyright : (C) 2016 by Juergen E. Fischer
6 email : jef at norbit dot de
7 ***************************************************************************/
8
9/***************************************************************************
10 * *
11 * This program is free software; you can redistribute it and/or modify *
12 * it under the terms of the GNU General Public License as published by *
13 * the Free Software Foundation; either version 2 of the License, or *
14 * (at your option) any later version. *
15 * *
16 ***************************************************************************/
17
18
19#include "qgsnetworkdiskcache.h"
20#include "moc_qgsnetworkdiskcache.cpp"
21
22#include <QStorageInfo>
23#include <mutex>
24
26ExpirableNetworkDiskCache QgsNetworkDiskCache::sDiskCache;
28QMutex QgsNetworkDiskCache::sDiskCacheMutex;
29
30QgsNetworkDiskCache::QgsNetworkDiskCache( QObject *parent )
31 : QNetworkDiskCache( parent )
32{
33}
34
36{
37 const QMutexLocker lock( &sDiskCacheMutex );
38 return sDiskCache.cacheDirectory();
39}
40
41void QgsNetworkDiskCache::setCacheDirectory( const QString &cacheDir )
42{
43 const QMutexLocker lock( &sDiskCacheMutex );
44 sDiskCache.setCacheDirectory( cacheDir );
45}
46
48{
49 const QMutexLocker lock( &sDiskCacheMutex );
50 return sDiskCache.maximumCacheSize();
51}
52
54{
55 const QMutexLocker lock( &sDiskCacheMutex );
56
57 if ( size == 0 )
58 {
59 // Calculate maximum cache size based on available free space
60 size = smartCacheSize( sDiskCache.cacheDirectory() );
61 }
62
63 sDiskCache.setMaximumCacheSize( size );
64}
65
67{
68 const QMutexLocker lock( &sDiskCacheMutex );
69 return sDiskCache.cacheSize();
70}
71
72QNetworkCacheMetaData QgsNetworkDiskCache::metaData( const QUrl &url )
73{
74 const QMutexLocker lock( &sDiskCacheMutex );
75 return sDiskCache.metaData( url );
76}
77
78void QgsNetworkDiskCache::updateMetaData( const QNetworkCacheMetaData &metaData )
79{
80 const QMutexLocker lock( &sDiskCacheMutex );
81 sDiskCache.updateMetaData( metaData );
82}
83
84QIODevice *QgsNetworkDiskCache::data( const QUrl &url )
85{
86 const QMutexLocker lock( &sDiskCacheMutex );
87 return sDiskCache.data( url );
88}
89
90bool QgsNetworkDiskCache::remove( const QUrl &url )
91{
92 const QMutexLocker lock( &sDiskCacheMutex );
93 return sDiskCache.remove( url );
94}
95
96QIODevice *QgsNetworkDiskCache::prepare( const QNetworkCacheMetaData &metaData )
97{
98 const QMutexLocker lock( &sDiskCacheMutex );
99 return sDiskCache.prepare( metaData );
100}
101
102void QgsNetworkDiskCache::insert( QIODevice *device )
103{
104 const QMutexLocker lock( &sDiskCacheMutex );
105 sDiskCache.insert( device );
106}
107
108QNetworkCacheMetaData QgsNetworkDiskCache::fileMetaData( const QString &fileName ) const
109{
110 const QMutexLocker lock( &sDiskCacheMutex );
111 return sDiskCache.fileMetaData( fileName );
112}
113
115{
116 const QMutexLocker lock( &sDiskCacheMutex );
117 return sDiskCache.runExpire();
118}
119
121{
122 const QMutexLocker lock( &sDiskCacheMutex );
123 return sDiskCache.clear();
124}
125
126void determineSmartCacheSize( const QString &cacheDir, qint64 &cacheSize )
127{
128 std::function<qint64( const QString & )> dirSize;
129 dirSize = [&dirSize]( const QString & dirPath ) -> qint64
130 {
131 qint64 size = 0;
132 QDir dir( dirPath );
133
134 const QStringList filePaths = dir.entryList( QDir::Files | QDir::System | QDir::Hidden );
135 for ( const QString &filePath : filePaths )
136 {
137 QFileInfo fi( dir, filePath );
138 size += fi.size();
139 }
140
141 const QStringList childDirPaths = dir.entryList( QDir::Dirs | QDir::NoDotAndDotDot | QDir::System | QDir::Hidden | QDir::NoSymLinks );
142 for ( const QString &childDirPath : childDirPaths )
143 {
144 size += dirSize( dirPath + QDir::separator() + childDirPath );
145 }
146
147 return size;
148 };
149
150 qint64 bytesFree;
151 QStorageInfo storageInfo( cacheDir );
152 bytesFree = storageInfo.bytesFree() + dirSize( cacheDir );
153
154 // NOLINTBEGIN(bugprone-narrowing-conversions)
155 // Logic taken from Firefox's smart cache size handling
156 qint64 available10MB = bytesFree / 1024 / ( 1024LL * 10 );
157 qint64 cacheSize10MB = 0;
158 if ( available10MB > 2500 )
159 {
160 // Cap the cache size to 1GB
161 cacheSize10MB = 100;
162 }
163 else
164 {
165 if ( available10MB > 700 )
166 {
167 // Add 2.5% of the free space above 7GB
168 cacheSize10MB += ( available10MB - 700 ) * 0.025;
169 available10MB = 700;
170 }
171 if ( available10MB > 50 )
172 {
173 // Add 7.5% of free space between 500MB to 7GB
174 cacheSize10MB += ( available10MB - 50 ) * 0.075;
175 available10MB = 50;
176 }
177
178#if defined( Q_OS_ANDROID )
179 // On Android, smaller/older devices may have very little storage
180
181 // Add 16% of free space up to 500 MB
182 cacheSize10MB += std::max( 2LL, static_cast<qint64>( available10MB * 0.16 ) );
183#else \
184 // Add 30% of free space up to 500 MB
185 cacheSize10MB += std::max( 5LL, static_cast<qint64>( available10MB * 0.30 ) );
186#endif
187 }
188 cacheSize = cacheSize10MB * 10 * 1024 * 1024;
189 // NOLINTEND(bugprone-narrowing-conversions)
190}
191
192qint64 QgsNetworkDiskCache::smartCacheSize( const QString &cacheDir )
193{
194 static qint64 sCacheSize = 0;
195 static std::once_flag initialized;
196 std::call_once( initialized, determineSmartCacheSize, cacheDir, sCacheSize );
197 return sCacheSize;
198}
void setCacheDirectory(const QString &cacheDir)
QIODevice * data(const QUrl &url) override
void updateMetaData(const QNetworkCacheMetaData &metaData) override
QNetworkCacheMetaData metaData(const QUrl &url) override
qint64 maximumCacheSize() const
QNetworkCacheMetaData fileMetaData(const QString &fileName) const
void insert(QIODevice *device) override
QIODevice * prepare(const QNetworkCacheMetaData &metaData) override
bool remove(const QUrl &url) override
void setMaximumCacheSize(qint64 size)
qint64 cacheSize() const override
QString cacheDirectory() const
static qint64 smartCacheSize(const QString &path)
Returns a smart cache size, in bytes, based on available free space.
void determineSmartCacheSize(const QString &cacheDir, qint64 &cacheSize)