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1 /**************************************************************************** |
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2 ** |
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3 ** |
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4 ** Implementation of QGCache and QGCacheIterator classes |
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5 ** |
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6 ** Created : 950208 |
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7 ** |
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8 ** Copyright (C) 1992-2000 Trolltech AS. All rights reserved. |
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9 ** |
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10 ** This file is part of the tools module of the Qt GUI Toolkit. |
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11 ** |
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12 ** This file may be distributed under the terms of the Q Public License |
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13 ** as defined by Trolltech AS of Norway and appearing in the file |
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14 ** LICENSE.QPL included in the packaging of this file. |
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15 ** |
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16 ** This file may be distributed and/or modified under the terms of the |
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17 ** GNU General Public License version 2 as published by the Free Software |
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18 ** Foundation and appearing in the file LICENSE.GPL included in the |
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19 ** packaging of this file. |
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20 ** |
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21 ** Licensees holding valid Qt Enterprise Edition or Qt Professional Edition |
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22 ** licenses may use this file in accordance with the Qt Commercial License |
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23 ** Agreement provided with the Software. |
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24 ** |
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25 ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE |
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26 ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
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27 ** |
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28 ** See http://www.trolltech.com/pricing.html or email sales@trolltech.com for |
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29 ** information about Qt Commercial License Agreements. |
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30 ** See http://www.trolltech.com/qpl/ for QPL licensing information. |
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31 ** See http://www.trolltech.com/gpl/ for GPL licensing information. |
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32 ** |
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33 ** Contact info@trolltech.com if any conditions of this licensing are |
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34 ** not clear to you. |
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35 ** |
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36 **********************************************************************/ |
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37 |
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38 #include "qgcache.h" |
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39 #include "qlist.h" |
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40 #include "qdict.h" |
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41 #include "qstring.h" |
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42 |
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43 |
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44 // NOT REVISED |
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45 /*! |
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46 \class QGCache qgcache.h |
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47 |
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48 \brief The QGCache class is an internal class for implementing QCache template classes. |
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49 |
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50 QGCache is a strictly internal class that acts as a base class for the |
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51 \link collection.html collection classes\endlink QCache and QIntCache. |
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52 */ |
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53 |
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54 |
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55 /***************************************************************************** |
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56 QGCacheItem class (internal cache item) |
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57 *****************************************************************************/ |
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58 |
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59 struct QCacheItem |
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60 { |
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61 QCacheItem( void *k, QCollection::Item d, int c, short p ) |
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62 : priority(p), skipPriority(p), cost(c), key(k), data(d), node(0) {} |
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63 short priority; |
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64 short skipPriority; |
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65 int cost; |
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66 void *key; |
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67 QCollection::Item data; |
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68 QLNode *node; |
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69 }; |
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70 |
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71 |
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72 /***************************************************************************** |
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73 QCList class (internal list of cache items) |
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74 *****************************************************************************/ |
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75 |
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76 class QCList : private QList<QCacheItem> |
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77 { |
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78 friend class QGCacheIterator; |
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79 friend class QCListIt; |
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80 public: |
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81 QCList() {} |
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82 ~QCList(); |
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83 |
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84 void insert( QCacheItem * ); // insert according to priority |
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85 void insert( int, QCacheItem * ); |
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86 void take( QCacheItem * ); |
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87 void reference( QCacheItem * ); |
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88 |
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89 void setAutoDelete( bool del ) { QCollection::setAutoDelete(del); } |
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90 |
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91 bool removeFirst() { return QList<QCacheItem>::removeFirst(); } |
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92 bool removeLast() { return QList<QCacheItem>::removeLast(); } |
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93 |
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94 QCacheItem *first() { return QList<QCacheItem>::first(); } |
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95 QCacheItem *last() { return QList<QCacheItem>::last(); } |
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96 QCacheItem *prev() { return QList<QCacheItem>::prev(); } |
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97 QCacheItem *next() { return QList<QCacheItem>::next(); } |
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98 |
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99 #if defined(DEBUG) |
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100 int inserts; // variables for statistics |
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101 int insertCosts; |
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102 int insertMisses; |
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103 int finds; |
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104 int hits; |
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105 int hitCosts; |
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106 int dumps; |
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107 int dumpCosts; |
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108 #endif |
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109 }; |
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110 |
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111 |
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112 QCList::~QCList() |
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113 { |
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114 #if defined(DEBUG) |
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115 ASSERT( count() == 0 ); |
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116 #endif |
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117 } |
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118 |
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119 |
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120 void QCList::insert( QCacheItem *ci ) |
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121 { |
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122 QCacheItem *item = first(); |
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123 while( item && item->skipPriority > ci->priority ) { |
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124 item->skipPriority--; |
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125 item = next(); |
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126 } |
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127 if ( item ) |
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128 QList<QCacheItem>::insert( at(), ci ); |
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129 else |
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130 append( ci ); |
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131 #if defined(DEBUG) |
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132 ASSERT( ci->node == 0 ); |
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133 #endif |
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134 ci->node = currentNode(); |
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135 } |
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136 |
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137 inline void QCList::insert( int i, QCacheItem *ci ) |
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138 { |
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139 QList<QCacheItem>::insert( i, ci ); |
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140 #if defined(DEBUG) |
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141 ASSERT( ci->node == 0 ); |
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142 #endif |
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143 ci->node = currentNode(); |
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144 } |
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145 |
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146 |
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147 void QCList::take( QCacheItem *ci ) |
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148 { |
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149 if ( ci ) { |
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150 #if defined(DEBUG) |
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151 ASSERT( ci->node != 0 ); |
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152 #endif |
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153 takeNode( ci->node ); |
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154 ci->node = 0; |
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155 } |
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156 } |
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157 |
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158 |
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159 inline void QCList::reference( QCacheItem *ci ) |
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160 { |
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161 #if defined(DEBUG) |
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162 ASSERT( ci != 0 && ci->node != 0 ); |
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163 #endif |
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164 ci->skipPriority = ci->priority; |
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165 relinkNode( ci->node ); // relink as first item |
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166 } |
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167 |
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168 |
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169 class QCListIt: public QListIterator<QCacheItem> |
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170 { |
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171 public: |
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172 QCListIt( const QCList *p ): QListIterator<QCacheItem>( *p ) {} |
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173 QCListIt( const QCListIt *p ): QListIterator<QCacheItem>( *p ) {} |
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174 }; |
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175 |
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176 |
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177 /***************************************************************************** |
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178 QCDict class (internal dictionary of cache items) |
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179 *****************************************************************************/ |
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180 |
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181 // |
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182 // Since we need to decide if the dictionary should use an int or const |
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183 // char * key (the "bool trivial" argument in the constructor below) |
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184 // we cannot use the macro/template dict, but inherit directly from QGDict. |
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185 // |
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186 |
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187 class QCDict : public QGDict |
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188 { |
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189 public: |
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190 QCDict( uint size, uint kt, bool caseSensitive, bool copyKeys ) |
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191 : QGDict( size, (KeyType)kt, caseSensitive, copyKeys ) {} |
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192 |
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193 QCacheItem *find_string(const QString &key) const |
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194 { return (QCacheItem*)((QCDict*)this)->look_string(key, 0, 0); } |
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195 QCacheItem *find_ascii(const char *key) const |
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196 { return (QCacheItem*)((QCDict*)this)->look_ascii(key, 0, 0); } |
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197 QCacheItem *find_int(long key) const |
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198 { return (QCacheItem*)((QCDict*)this)->look_int(key, 0, 0); } |
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199 |
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200 QCacheItem *take_string(const QString &key) |
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201 { return (QCacheItem*)QGDict::take_string(key); } |
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202 QCacheItem *take_ascii(const char *key) |
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203 { return (QCacheItem*)QGDict::take_ascii(key); } |
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204 QCacheItem *take_int(long key) |
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205 { return (QCacheItem*)QGDict::take_int(key); } |
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206 |
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207 bool insert_string( const QString &key, const QCacheItem *ci ) |
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208 { return QGDict::look_string(key,(Item)ci,1)!=0;} |
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209 bool insert_ascii( const char *key, const QCacheItem *ci ) |
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210 { return QGDict::look_ascii(key,(Item)ci,1)!=0;} |
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211 bool insert_int( long key, const QCacheItem *ci ) |
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212 { return QGDict::look_int(key,(Item)ci,1)!=0;} |
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213 |
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214 bool remove_string( QCacheItem *item ) |
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215 { return QGDict::remove_string(*((QString*)(item->key)),item); } |
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216 bool remove_ascii( QCacheItem *item ) |
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217 { return QGDict::remove_ascii((const char *)item->key,item); } |
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218 bool remove_int( QCacheItem *item ) |
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219 { return QGDict::remove_int((long)item->key,item);} |
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220 |
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221 void statistics() { QGDict::statistics(); } |
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222 }; |
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223 |
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224 |
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225 /***************************************************************************** |
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226 QGDict member functions |
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227 *****************************************************************************/ |
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228 |
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229 /*! |
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230 \internal |
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231 Constructs a cache. |
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232 */ |
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233 |
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234 QGCache::QGCache( int maxCost, uint size, KeyType kt, bool caseSensitive, |
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235 bool copyKeys ) |
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236 { |
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237 keytype = kt; |
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238 lruList = new QCList; |
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239 CHECK_PTR( lruList ); |
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240 lruList->setAutoDelete( TRUE ); |
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241 copyk = ((keytype == AsciiKey) && copyKeys); |
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242 dict = new QCDict( size, kt, caseSensitive, FALSE ); |
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243 CHECK_PTR( dict ); |
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244 mCost = maxCost; |
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245 tCost = 0; |
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246 #if defined(DEBUG) |
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247 lruList->inserts = 0; |
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248 lruList->insertCosts = 0; |
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249 lruList->insertMisses = 0; |
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250 lruList->finds = 0; |
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251 lruList->hits = 0; |
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252 lruList->hitCosts = 0; |
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253 lruList->dumps = 0; |
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254 lruList->dumpCosts = 0; |
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255 #endif |
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256 } |
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257 |
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258 /*! |
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259 \internal |
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260 Cannot copy a cache. |
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261 */ |
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262 |
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263 QGCache::QGCache( const QGCache & ) |
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264 : QCollection() |
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265 { |
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266 #if defined(CHECK_NULL) |
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267 qFatal( "QGCache::QGCache(QGCache &): Cannot copy a cache" ); |
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268 #endif |
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269 } |
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270 |
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271 /*! |
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272 \internal |
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273 Removes all items from the cache and destroys it. |
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274 */ |
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275 |
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276 QGCache::~QGCache() |
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277 { |
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278 clear(); // delete everything first |
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279 delete dict; |
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280 delete lruList; |
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281 } |
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282 |
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283 /*! |
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284 \internal |
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285 Cannot assign a cache. |
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286 */ |
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287 |
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288 QGCache &QGCache::operator=( const QGCache & ) |
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289 { |
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290 #if defined(CHECK_NULL) |
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291 qFatal( "QGCache::operator=: Cannot copy a cache" ); |
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292 #endif |
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293 return *this; // satisfy the compiler |
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294 } |
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295 |
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296 |
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297 /*! |
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298 \fn uint QGCache::count() const |
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299 \internal |
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300 Returns the number of items in the cache. |
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301 */ |
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302 |
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303 /*! |
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304 \fn uint QGCache::size() const |
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305 \internal |
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306 Returns the size of the hash array. |
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307 */ |
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308 |
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309 /*! |
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310 \fn int QGCache::maxCost() const |
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311 \internal |
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312 Returns the maximum cache cost. |
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313 */ |
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314 |
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315 /*! |
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316 \fn int QGCache::totalCost() const |
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317 \internal |
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318 Returns the total cache cost. |
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319 */ |
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320 |
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321 /*! |
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322 \internal |
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323 Sets the maximum cache cost. |
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324 */ |
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325 |
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326 void QGCache::setMaxCost( int maxCost ) |
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327 { |
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328 if ( maxCost < tCost ) { |
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329 if ( !makeRoomFor(tCost - maxCost) ) // remove excess cost |
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330 return; |
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331 } |
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332 mCost = maxCost; |
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333 } |
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334 |
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335 |
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336 /*! |
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337 \internal |
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338 Inserts an item into the cache. |
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339 |
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340 \warning If this function returns FALSE, you must delete \a data |
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341 yourself. Additionally, be very careful about using \a data after |
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342 calling this function, as any other insertions into the cache, from |
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343 anywhere in the application, or within Qt itself, could cause the |
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344 data to be discarded from the cache, and the pointer to become |
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345 invalid. |
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346 */ |
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347 |
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348 bool QGCache::insert_string( const QString &key, QCollection::Item data, |
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349 int cost, int priority) |
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350 { |
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351 if ( tCost + cost > mCost ) { |
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352 if ( !makeRoomFor(tCost + cost - mCost, priority) ) { |
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353 #if defined(DEBUG) |
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354 lruList->insertMisses++; |
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355 #endif |
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356 return FALSE; |
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357 } |
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358 } |
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359 #if defined(DEBUG) |
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360 ASSERT( keytype == StringKey ); |
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361 lruList->inserts++; |
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362 lruList->insertCosts += cost; |
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363 #endif |
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364 if ( priority < -32768 ) |
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365 priority = -32768; |
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366 else if ( priority > 32767 ) |
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367 priority = 32677; |
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368 QCacheItem *ci = new QCacheItem( new QString(key), newItem(data), |
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369 cost, (short)priority ); |
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370 CHECK_PTR( ci ); |
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371 lruList->insert( 0, ci ); |
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372 dict->insert_string( key, ci ); |
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373 tCost += cost; |
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374 return TRUE; |
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375 } |
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376 |
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377 |
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378 /*! \internal */ |
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379 |
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380 bool QGCache::insert_other( const char *key, QCollection::Item data, |
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381 int cost, int priority) |
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382 { |
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383 if ( tCost + cost > mCost ) { |
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384 if ( !makeRoomFor(tCost + cost - mCost, priority) ) { |
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385 #if defined(DEBUG) |
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386 lruList->insertMisses++; |
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387 #endif |
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388 return FALSE; |
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389 } |
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390 } |
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391 #if defined(DEBUG) |
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392 ASSERT( keytype != StringKey ); |
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393 lruList->inserts++; |
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394 lruList->insertCosts += cost; |
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395 #endif |
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396 if ( keytype == AsciiKey && copyk ) |
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397 key = qstrdup( key ); |
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398 if ( priority < -32768 ) |
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399 priority = -32768; |
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400 else if ( priority > 32767 ) |
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401 priority = 32677; |
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402 QCacheItem *ci = new QCacheItem( (void*)key, newItem(data), cost, |
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403 (short)priority ); |
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404 CHECK_PTR( ci ); |
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405 lruList->insert( 0, ci ); |
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406 if ( keytype == AsciiKey ) |
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407 dict->insert_ascii( key, ci ); |
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408 else |
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409 dict->insert_int( (long)key, ci ); |
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410 tCost += cost; |
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411 return TRUE; |
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412 } |
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413 |
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414 |
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415 /*! |
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416 \internal |
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417 Removes an item from the cache. |
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418 */ |
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419 |
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420 bool QGCache::remove_string( const QString &key ) |
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421 { |
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422 Item d = take_string( key ); |
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423 if ( d ) |
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424 deleteItem( d ); |
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425 return d != 0; |
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426 } |
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427 |
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428 |
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429 /*! \internal */ |
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430 |
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431 bool QGCache::remove_other( const char *key ) |
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432 { |
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433 Item d = take_other( key ); |
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434 if ( d ) |
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435 deleteItem( d ); |
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436 return d != 0; |
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437 } |
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438 |
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439 |
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440 /*! |
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441 \internal |
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442 Takes an item out of the cache (no delete). |
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443 */ |
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444 |
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445 QCollection::Item QGCache::take_string( const QString &key ) |
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446 { |
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447 QCacheItem *ci = dict->take_string( key ); // take from dict |
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448 Item d; |
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449 if ( ci ) { |
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450 d = ci->data; |
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451 tCost -= ci->cost; |
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452 lruList->take( ci ); // take from list |
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453 delete (QString*)ci->key; |
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454 delete ci; |
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455 } else { |
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456 d = 0; |
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457 } |
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458 return d; |
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459 } |
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460 |
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461 /*! |
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462 \internal |
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463 Takes an item out of the cache (no delete). |
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464 */ |
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465 |
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466 QCollection::Item QGCache::take_other( const char *key ) |
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467 { |
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468 QCacheItem *ci; |
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469 if ( keytype == AsciiKey ) |
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470 ci = dict->take_ascii( key ); |
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471 else |
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472 ci = dict->take_int( (long)key ); |
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473 Item d; |
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474 if ( ci ) { |
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475 d = ci->data; |
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476 tCost -= ci->cost; |
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477 lruList->take( ci ); // take from list |
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478 if ( copyk ) |
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479 delete [] (char *)ci->key; |
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480 delete ci; |
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481 } else { |
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482 d = 0; |
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483 } |
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484 return d; |
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485 } |
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486 |
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487 |
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488 /*! |
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489 \internal |
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490 Clears the cache. |
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491 */ |
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492 |
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493 void QGCache::clear() |
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494 { |
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495 QCacheItem *ci; |
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496 while ( (ci = lruList->first()) ) { |
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497 switch ( keytype ) { |
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498 case StringKey: |
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499 dict->remove_string( ci ); |
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500 delete (QString*)ci->key; |
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501 break; |
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502 case AsciiKey: |
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503 dict->remove_ascii( ci ); |
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504 if ( copyk ) |
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505 delete [] (char*)ci->key; |
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506 break; |
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507 case IntKey: |
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508 dict->remove_int( ci ); |
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509 break; |
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510 case PtrKey: // unused |
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511 break; |
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512 } |
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513 deleteItem( ci->data ); // delete data |
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514 lruList->removeFirst(); // remove from list |
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515 } |
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516 tCost = 0; |
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517 } |
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518 |
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519 |
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520 /*! |
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521 \internal |
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522 Finds an item in the cache. |
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523 */ |
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524 |
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525 QCollection::Item QGCache::find_string( const QString &key, bool ref ) const |
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526 { |
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527 QCacheItem *ci = dict->find_string( key ); |
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528 #if defined(DEBUG) |
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529 lruList->finds++; |
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530 #endif |
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531 if ( ci ) { |
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532 #if defined(DEBUG) |
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533 lruList->hits++; |
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534 lruList->hitCosts += ci->cost; |
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535 #endif |
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536 if ( ref ) |
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537 lruList->reference( ci ); |
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538 return ci->data; |
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539 } |
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540 return 0; |
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541 } |
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542 |
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543 |
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544 /*! |
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545 \internal |
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546 Finds an item in the cache. |
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547 */ |
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548 |
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549 QCollection::Item QGCache::find_other( const char *key, bool ref ) const |
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550 { |
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551 QCacheItem *ci = keytype == AsciiKey ? dict->find_ascii(key) |
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552 : dict->find_int((long)key); |
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553 #if defined(DEBUG) |
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554 lruList->finds++; |
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555 #endif |
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556 if ( ci ) { |
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557 #if defined(DEBUG) |
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558 lruList->hits++; |
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559 lruList->hitCosts += ci->cost; |
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560 #endif |
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561 if ( ref ) |
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562 lruList->reference( ci ); |
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563 return ci->data; |
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564 } |
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565 return 0; |
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566 } |
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567 |
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568 |
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569 /*! |
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570 \internal |
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571 Allocates cache space for one or more items. |
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572 */ |
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573 |
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574 bool QGCache::makeRoomFor( int cost, int priority ) |
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575 { |
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576 if ( cost > mCost ) // cannot make room for more |
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577 return FALSE; // than maximum cost |
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578 if ( priority == -1 ) |
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579 priority = 32767; |
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580 register QCacheItem *ci = lruList->last(); |
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581 int cntCost = 0; |
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582 int dumps = 0; // number of items to dump |
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583 while ( cntCost < cost && ci && ci->skipPriority <= priority ) { |
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584 cntCost += ci->cost; |
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585 ci = lruList->prev(); |
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586 dumps++; |
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587 } |
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588 if ( cntCost < cost ) // can enough cost be dumped? |
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589 return FALSE; // no |
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590 #if defined(DEBUG) |
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591 ASSERT( dumps > 0 ); |
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592 #endif |
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593 while ( dumps-- ) { |
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594 ci = lruList->last(); |
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595 #if defined(DEBUG) |
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596 lruList->dumps++; |
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597 lruList->dumpCosts += ci->cost; |
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598 #endif |
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599 switch ( keytype ) { |
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600 case StringKey: |
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601 dict->remove_string( ci ); |
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602 delete (QString*)ci->key; |
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603 break; |
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604 case AsciiKey: |
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605 dict->remove_ascii( ci ); |
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606 if ( copyk ) |
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607 delete [] (char *)ci->key; |
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608 break; |
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609 case IntKey: |
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610 dict->remove_int( ci ); |
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611 break; |
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612 case PtrKey: // unused |
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613 break; |
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614 } |
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615 deleteItem( ci->data ); // delete data |
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616 lruList->removeLast(); // remove from list |
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617 } |
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618 tCost -= cntCost; |
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619 return TRUE; |
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620 } |
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621 |
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622 |
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623 /*! |
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624 \internal |
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625 Outputs debug statistics. |
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626 */ |
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627 |
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628 void QGCache::statistics() const |
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629 { |
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630 #if defined(DEBUG) |
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631 QString line; |
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632 line.fill( '*', 80 ); |
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633 qDebug( line.ascii() ); |
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634 qDebug( "CACHE STATISTICS:" ); |
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635 qDebug( "cache contains %d item%s, with a total cost of %d", |
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636 count(), count() != 1 ? "s" : "", tCost ); |
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637 qDebug( "maximum cost is %d, cache is %d%% full.", |
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638 mCost, (200*tCost + mCost) / (mCost*2) ); |
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639 qDebug( "find() has been called %d time%s", |
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640 lruList->finds, lruList->finds != 1 ? "s" : "" ); |
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641 qDebug( "%d of these were hits, items found had a total cost of %d.", |
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642 lruList->hits,lruList->hitCosts ); |
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643 qDebug( "%d item%s %s been inserted with a total cost of %d.", |
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644 lruList->inserts,lruList->inserts != 1 ? "s" : "", |
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645 lruList->inserts != 1 ? "have" : "has", lruList->insertCosts ); |
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646 qDebug( "%d item%s %s too large or had too low priority to be inserted.", |
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647 lruList->insertMisses, lruList->insertMisses != 1 ? "s" : "", |
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648 lruList->insertMisses != 1 ? "were" : "was" ); |
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649 qDebug( "%d item%s %s been thrown away with a total cost of %d.", |
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650 lruList->dumps, lruList->dumps != 1 ? "s" : "", |
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651 lruList->dumps != 1 ? "have" : "has", lruList->dumpCosts ); |
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652 qDebug( "Statistics from internal dictionary class:" ); |
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653 dict->statistics(); |
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654 qDebug( line.ascii() ); |
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655 #endif |
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656 } |
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657 |
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658 |
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659 /***************************************************************************** |
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660 QGCacheIterator member functions |
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661 *****************************************************************************/ |
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662 |
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663 /*! |
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664 \class QGCacheIterator qgcache.h |
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665 |
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666 \brief An internal class for implementing QCacheIterator and QIntCacheIterator. |
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667 |
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668 QGCacheIterator is a strictly internal class that does the heavy work for |
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669 QCacheIterator and QIntCacheIterator. |
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670 */ |
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671 |
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672 /*! |
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673 \internal |
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674 Constructs an iterator that operates on the cache \e c. |
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675 */ |
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676 |
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677 QGCacheIterator::QGCacheIterator( const QGCache &c ) |
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678 { |
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679 it = new QCListIt( c.lruList ); |
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680 #if defined(DEBUG) |
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681 ASSERT( it != 0 ); |
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682 #endif |
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683 } |
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684 |
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685 /*! |
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686 \internal |
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687 Constructs an iterator that operates on the same cache as \e ci. |
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688 */ |
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689 |
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690 QGCacheIterator::QGCacheIterator( const QGCacheIterator &ci ) |
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691 { |
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692 it = new QCListIt( ci.it ); |
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693 #if defined(DEBUG) |
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694 ASSERT( it != 0 ); |
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695 #endif |
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696 } |
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697 |
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698 /*! |
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699 \internal |
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700 Destroys the iterator. |
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701 */ |
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702 |
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703 QGCacheIterator::~QGCacheIterator() |
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704 { |
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705 delete it; |
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706 } |
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707 |
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708 /*! |
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709 \internal |
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710 Assigns the iterator \e ci to this cache iterator. |
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711 */ |
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712 |
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713 QGCacheIterator &QGCacheIterator::operator=( const QGCacheIterator &ci ) |
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714 { |
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715 *it = *ci.it; |
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716 return *this; |
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717 } |
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718 |
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719 /*! |
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720 \internal |
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721 Returns the number of items in the cache. |
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722 */ |
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723 |
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724 uint QGCacheIterator::count() const |
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725 { |
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726 return it->count(); |
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727 } |
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728 |
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729 /*! |
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730 \internal |
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731 Returns TRUE if the iterator points to the first item. |
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732 */ |
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733 |
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734 bool QGCacheIterator::atFirst() const |
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735 { |
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736 return it->atFirst(); |
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737 } |
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738 |
|
739 /*! |
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740 \internal |
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741 Returns TRUE if the iterator points to the last item. |
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742 */ |
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743 |
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744 bool QGCacheIterator::atLast() const |
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745 { |
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746 return it->atLast(); |
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747 } |
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748 |
|
749 /*! |
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750 \internal |
|
751 Sets the list iterator to point to the first item in the cache. |
|
752 */ |
|
753 |
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754 QCollection::Item QGCacheIterator::toFirst() |
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755 { |
|
756 QCacheItem *item = it->toFirst(); |
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757 return item ? item->data : 0; |
|
758 } |
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759 |
|
760 /*! |
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761 \internal |
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762 Sets the list iterator to point to the last item in the cache. |
|
763 */ |
|
764 |
|
765 QCollection::Item QGCacheIterator::toLast() |
|
766 { |
|
767 QCacheItem *item = it->toLast(); |
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768 return item ? item->data : 0; |
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769 } |
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770 |
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771 /*! |
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772 \internal |
|
773 Returns the current item. |
|
774 */ |
|
775 |
|
776 QCollection::Item QGCacheIterator::get() const |
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777 { |
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778 QCacheItem *item = it->current(); |
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779 return item ? item->data : 0; |
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780 } |
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781 |
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782 /*! |
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783 \internal |
|
784 Returns the key of the current item. |
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785 */ |
|
786 |
|
787 QString QGCacheIterator::getKeyString() const |
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788 { |
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789 QCacheItem *item = it->current(); |
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790 return item ? *((QString*)item->key) : QString::null; |
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791 } |
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792 |
|
793 /*! |
|
794 \internal |
|
795 Returns the key of the current item, as a \0-terminated C string. |
|
796 */ |
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797 |
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798 const char *QGCacheIterator::getKeyAscii() const |
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799 { |
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800 QCacheItem *item = it->current(); |
|
801 return item ? (const char *)item->key : 0; |
|
802 } |
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803 |
|
804 /*! |
|
805 \internal |
|
806 Returns the key of the current item, as a long. |
|
807 */ |
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808 |
|
809 long QGCacheIterator::getKeyInt() const |
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810 { |
|
811 QCacheItem *item = it->current(); |
|
812 return item ? (long)item->key : 0; |
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813 } |
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814 |
|
815 /*! |
|
816 \internal |
|
817 Moves to the next item (postfix). |
|
818 */ |
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819 |
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820 QCollection::Item QGCacheIterator::operator()() |
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821 { |
|
822 QCacheItem *item = it->operator()(); |
|
823 return item ? item->data : 0; |
|
824 } |
|
825 |
|
826 /*! |
|
827 \internal |
|
828 Moves to the next item (prefix). |
|
829 */ |
|
830 |
|
831 QCollection::Item QGCacheIterator::operator++() |
|
832 { |
|
833 QCacheItem *item = it->operator++(); |
|
834 return item ? item->data : 0; |
|
835 } |
|
836 |
|
837 /*! |
|
838 \internal |
|
839 Moves \e jumps positions forward. |
|
840 */ |
|
841 |
|
842 QCollection::Item QGCacheIterator::operator+=( uint jump ) |
|
843 { |
|
844 QCacheItem *item = it->operator+=(jump); |
|
845 return item ? item->data : 0; |
|
846 } |
|
847 |
|
848 /*! |
|
849 \internal |
|
850 Moves to the previous item (prefix). |
|
851 */ |
|
852 |
|
853 QCollection::Item QGCacheIterator::operator--() |
|
854 { |
|
855 QCacheItem *item = it->operator--(); |
|
856 return item ? item->data : 0; |
|
857 } |
|
858 |
|
859 /*! |
|
860 \internal |
|
861 Moves \e jumps positions backward. |
|
862 */ |
|
863 |
|
864 QCollection::Item QGCacheIterator::operator-=( uint jump ) |
|
865 { |
|
866 QCacheItem *item = it->operator-=(jump); |
|
867 return item ? item->data : 0; |
|
868 } |