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1 // Copyright (c) 2008-2009 Nokia Corporation and/or its subsidiary(-ies). |
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2 // All rights reserved. |
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3 // This component and the accompanying materials are made available |
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4 // under the terms of "Eclipse Public License v1.0" |
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5 // which accompanies this distribution, and is available |
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6 // at the URL "http://www.eclipse.org/legal/epl-v10.html". |
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7 // |
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8 // Initial Contributors: |
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9 // Nokia Corporation - initial contribution. |
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10 // |
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11 // Contributors: |
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12 // |
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13 // Description: |
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14 // |
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15 |
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16 #include <e32std.h> |
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17 #include <f32file.h> |
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18 #include <e32test.h> |
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19 #include <euserhl.h> |
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20 |
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21 |
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22 |
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23 // Note: Methods are defined inline within classes here simply to make |
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24 // the code shorter, keep related code closer together, and hopefully |
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25 // make things easier to follow. |
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26 |
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27 RTest test(_L("EuserHl Walkthrough")); |
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28 |
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29 // Some dummy methods and data used in the walkthroughs below |
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30 _LIT(KFill, "XXX"); |
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31 _LIT(KPath, "c:\\a\\b\\c"); |
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32 _LIT(KOne, "One "); |
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33 _LIT(KTwo, "Two "); |
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34 _LIT(KTesting, "Testing "); |
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35 |
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36 void MaybeLeaveL() |
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37 { |
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38 // Some code that may leave |
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39 } |
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40 |
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41 HBufC* AllocateNameL(const TDesC& aDes) |
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42 { |
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43 return aDes.AllocL(); |
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44 } |
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45 |
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46 void ReadToMax(TDes& aDes) |
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47 { |
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48 aDes.SetMax(); |
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49 aDes.Repeat(KFill); |
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50 } |
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51 |
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52 void GetCurrentPath(TDes& aDes) |
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53 { |
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54 aDes = KPath; |
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55 } |
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56 |
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57 void GetCurrentPathStringL(LString& aString) |
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58 { |
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59 aString = L"c:\\a\\b\\c"; // Will auto-grow if necessary, may leave |
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60 } |
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61 |
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62 LString AppendCurrentPathStringL(LString aString) |
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63 { |
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64 return aString+= L"c:\\a\\b\\c"; |
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65 } |
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66 |
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67 class CTicker : public CBase |
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68 { |
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69 public: |
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70 void Tick() { ++iTicks; } |
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71 void Tock() { ++iTocks; } |
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72 |
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73 void Zap() { delete this; } |
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74 |
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75 public: |
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76 TInt iTicks; |
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77 TInt iTocks; |
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78 }; |
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79 |
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80 // Defines a custom pointer cleanup policy that calls the Zap member |
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81 class TTickerZapStrategy |
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82 { |
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83 public: |
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84 static void Cleanup(CTicker* aPtr) |
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85 { |
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86 // The general template/class scaffolding remains the same |
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87 // for all custom cleanups, just this cleanup body varies |
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88 aPtr->Zap(); |
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89 test.Printf(_L("Zapped CTicker\n")); |
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90 } |
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91 }; |
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92 |
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93 void RegisterTicker(CTicker& aTicker) |
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94 { |
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95 (void)aTicker; |
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96 } |
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97 |
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98 void RegisterTickerPtr(CTicker* aTicker) |
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99 { |
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100 (void)aTicker; |
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101 } |
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102 |
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103 void TakeTickerOwnership(CTicker* aTicker) |
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104 { |
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105 delete aTicker; |
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106 } |
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107 |
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108 void RegisterTimer(RTimer& aTimer) |
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109 { |
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110 (void)aTimer; |
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111 } |
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112 |
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113 // Defines a custom handle cleanup policy that calls Cancel then Close |
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114 class TCancelClose |
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115 { |
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116 public: |
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117 template <class T> |
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118 static void Cleanup(T* aHandle) |
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119 { |
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120 // The general template/class scaffolding remains the same |
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121 // for all custom cleanups, just this cleanup body varies |
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122 aHandle->Cancel(); |
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123 aHandle->Close(); |
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124 test.Printf(_L("Cancel Closed RTimer\n")); |
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125 } |
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126 }; |
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127 |
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128 void BespokeCleanupFunction(TAny* aData) |
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129 { |
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130 (void)aData; |
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131 test.Printf(_L("BespokeCleanupFunction\n")); |
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132 } |
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133 |
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134 // The walkthroughs themselves |
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135 |
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136 // This class demonstrates the use of an embedded LString in the |
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137 // conventional Symbian two-phase construction pattern. We've chosen |
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138 // to implement the temporary leave protection in NewL in terms of |
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139 // LCleanedupPtr instead of the the CleanupStack API in this example. |
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140 class CStringUserTwoPhase : public CBase |
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141 { |
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142 public: |
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143 static CStringUserTwoPhase* NewL(const TDesC& aName) |
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144 { |
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145 // We can use the resource management utility classes in |
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146 // two-phase if we want to |
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147 LCleanedupPtr<CStringUserTwoPhase> self(new(ELeave) CStringUserTwoPhase); |
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148 self->ConstructL(aName); |
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149 // Calling Unmanage() disables cleanup and yields the |
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150 // previously managed pointer so that it can be safely |
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151 // returned |
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152 return self.Unmanage(); |
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153 } |
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154 |
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155 virtual void ConstructL(const TDesC& aName) |
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156 { |
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157 // This assignment may leave if LString fails to allocate a |
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158 // heap buffer large enough to hold the data in aName |
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159 iName = aName; |
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160 } |
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161 |
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162 ~CStringUserTwoPhase() |
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163 { |
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164 // The iName LString cleans up after itself automatically |
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165 } |
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166 |
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167 const TDesC& Name() |
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168 { |
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169 // We can just return an LString directly as a const TDesC |
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170 return iName; |
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171 } |
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172 |
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173 protected: |
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174 CStringUserTwoPhase() |
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175 { |
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176 // Everything interesting happens in ConstructL in this |
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177 // version. |
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178 |
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179 // Default initialization of the iName LString does not |
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180 // allocate a heap buffer, and so cannot leave. As long as |
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181 // initialization is deferred to ConstructL, LStrings can be |
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182 // used safely with two-phase construction. |
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183 } |
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184 |
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185 protected: |
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186 LString iName; |
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187 }; |
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188 |
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189 // This class demonstrates the use of an embedded LString in the |
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190 // single-phase construction pattern, where a leave-safe constructor |
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191 // fully initializes the object. |
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192 // |
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193 // Note that where a class's constructor forms part of its exported |
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194 // public or protected contract, switching from a non-leaving to a |
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195 // potentially leaving constructor would be a BC break. On the other |
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196 // hand, if instantiation is entirely encapsulated within factory |
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197 // functions like NewL, there is no such BC restriction. |
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198 class CStringUserSinglePhase : public CBase |
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199 { |
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200 public: |
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201 // This macro is necessary to ensure cleanup is correctly handled |
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202 // in the event that a constructor may leave beneath a call to |
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203 // new(ELeave) |
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204 CONSTRUCTORS_MAY_LEAVE |
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205 |
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206 static CStringUserSinglePhase* NewL(const TDesC& aName) |
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207 { |
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208 return new(ELeave) CStringUserSinglePhase(aName); |
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209 } |
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210 |
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211 ~CStringUserSinglePhase() |
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212 { |
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213 // The iName LString cleans up after itself automatically |
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214 } |
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215 |
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216 const TDesC& Name() |
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217 { |
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218 // We can just return an LString directly as a const TDesC |
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219 return iName; |
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220 } |
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221 |
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222 protected: |
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223 CStringUserSinglePhase(const TDesC& aName) |
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224 // This initialization of iName may leave because LString |
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225 // needs to allocate a heap buffer to copy the aName string |
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226 // data into |
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227 : iName(aName) |
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228 { |
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229 // If iName initialization is successful but the constructor |
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230 // then goes on to leave later, iName (like all fields fully |
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231 // constructed at the point of a leave in a constructor) will |
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232 // be destructed, and so clean up after itself |
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233 MaybeLeaveL(); |
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234 } |
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235 |
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236 protected: |
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237 LString iName; |
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238 }; |
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239 |
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240 |
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241 void WalkthroughStringsL() |
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242 { |
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243 |
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244 { |
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245 // Trivially exercise the LString using classes defined above |
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246 |
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247 LCleanedupPtr<CStringUserTwoPhase> one(CStringUserTwoPhase::NewL(KOne)); |
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248 test.Printf(_L("Single phase name: %S\n"), &one->Name()); |
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249 |
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250 LCleanedupPtr<CStringUserSinglePhase> two(CStringUserSinglePhase::NewL(KTwo)); |
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251 test.Printf(_L("Two phase name: %S\n"), &two->Name()); |
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252 |
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253 // Both instances are automatically deleted as we go out of scope |
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254 } |
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255 |
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256 { |
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257 // A default constructed LString starts empty, doesn't |
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258 // allocate any memory on the heap, and therefore the |
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259 // following cannot leave |
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260 LString s; |
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261 |
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262 // But it will grow on demand if you assign to it, so it has |
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263 // enough space to hold the copied string data, and so |
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264 // assignment may leave |
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265 s = L"One "; |
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266 |
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267 // Similarly if you append to it with the leaving variant of |
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268 // Append, AppendL, if may grow on demand |
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269 s.AppendL(L"Two "); |
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270 |
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271 // The += operator for LString also maps to AppendL |
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272 s += L"Three "; |
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273 |
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274 // You can also use new leaving format methods that also grow |
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275 // on demand |
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276 s.AppendFormatL(KTesting); |
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277 |
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278 // This general style of use of LString may be preferable to |
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279 // typical descriptor use for a number of reasons e.g. it |
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280 // avoids the common temptation to set an artificial maximum |
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281 // buffer size; it avoids massive conservative over-allocation |
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282 // when the average case length of a string is far less than |
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283 // the worst-case maximum; it will not surprise you (compared |
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284 // to the alternative of a large stack-allocated TBuf) by |
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285 // triggering stack overflow. |
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286 |
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287 // An LString can be printed the same way as any descriptor |
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288 test.Printf(_L("Value: %S\n"), &s); |
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289 |
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290 // An LString supports all TDesC and TDes methods |
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291 // LString findToken(L"Two "); |
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292 test(s.Find(L"Two ") == 4); |
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293 |
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294 // LString matchPattern(L"*Two* "); |
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295 test(s.Match(L"*Two*") == 4); |
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296 test(s.Match(L"*T?o*") == 4); |
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297 |
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298 // LString compare(L"some string"); |
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299 test(s.Compare(L"One Two Three Testing ") == 0); |
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300 test(s.Compare(L"One Two Three Testing! ") < 0); |
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301 test(s.Compare(L"One Two Testing ") > 0); |
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302 |
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303 // also LString ==,!=,>,<,<=,>=(L"some string"); |
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304 test(s == L"One Two Three Testing "); |
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305 test(s < L"One Two Three Testing! "); |
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306 test(s > L"One Two Testing "); |
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307 test(s != L"not equal"); |
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308 |
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309 // An LString supports all TDesC and TDes operators |
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310 test(s[4] == TChar('T')); |
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311 |
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312 TInt untrimmed = s.Length(); |
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313 s.Trim(); |
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314 test(s.Length() == untrimmed - 1); |
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315 |
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316 s.UpperCase(); |
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317 test.Printf(_L("UpperCase: %S\n"), &s); |
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318 s.LowerCase(); |
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319 test.Printf(_L("LowerCase: %S\n"), &s); |
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320 |
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321 // The underlying heap allocated buffer is released |
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322 // automatically when the LString goes out of scope, either |
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323 // normally or through a leave |
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324 } |
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325 { |
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326 // Copy, Append,Insert,Replace,Justify the same way as TDesC and TDes |
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327 |
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328 LString s; |
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329 // Copies data into this 8-bit string descriptor, replacing any existing |
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330 // data, and expanding its heap buffer to accommodate if necessary. |
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331 // leaves on not being able to accomodate the new content |
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332 // both AssignL and += use CopyL internally |
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333 s.CopyL(L"new way of dealing with strings"); |
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334 s.CopyUCL(L"new way of dealing with strings"); |
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335 test(s == L"NEW WAY OF DEALING WITH STRINGS"); |
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336 |
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337 // Insert data into this descriptor. |
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338 // The length of this descriptor is changed to reflect the extra data. |
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339 // This leaving variant of the standard, non-leaving descriptor method |
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340 // differs in that this operation may cause the string descriptor's heap |
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341 // buffer to be reallocated in order to accommodate the new data. As a |
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342 // result, MaxLength() and Ptr() may return different values afterwards, |
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343 // and any existing raw pointers to into the descriptor data may be |
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344 // invalidated. |
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345 s.CopyL(L"Some Content Can Be Into This String"); |
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346 s.InsertL(20,L"Inserted "); |
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347 test(s == L"Some Content Can Be Inserted Into This String"); |
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348 |
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349 // Replace data in this descriptor. |
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350 // The specified length can be different to the length of the replacement data. |
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351 // The length of this descriptor changes to reflect the change of data. |
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352 // This leaving variant of the standard, non-leaving descriptor method |
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353 // differs in that this operation may cause the string descriptor's heap |
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354 // buffer to be reallocated in order to accommodate the new data. As a |
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355 // result, MaxLength() and Ptr() may return different values afterwards, |
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356 // and any existing raw pointers to into the descriptor data may be |
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357 // invalidated. |
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358 s.CopyL(L"Some Content Can Be Decalper"); |
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359 s.ReplaceL(20,8,L"Replaced"); |
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360 test(s == L"Some Content Can Be Replaced"); |
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361 |
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362 // Append data onto the end of this descriptor's data. |
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363 // The length of this descriptor is incremented to reflect the new content. |
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364 // This leaving variant of the standard, non-leaving descriptor method |
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365 // differs in that this operation may cause the string descriptor's heap |
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366 // buffer to be reallocated in order to accommodate the new data. As a |
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367 // result, MaxLength() and Ptr() may return different values afterwards, |
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368 // and any existing raw pointers to into the descriptor data may be |
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369 // invalidated. |
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370 s.CopyL(L"Try appending "); |
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371 s.AppendL(L"Try appending some more",3); |
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372 test(s == L"Try appending Try"); |
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373 |
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374 // Copy data into this descriptor and justifies it, replacing any existing data. |
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375 // The length of this descriptor is set to reflect the new data. |
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376 // The target area is considered to be an area of specified width positioned at |
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377 // the beginning of this descriptor's data area. Source data is copied into, and |
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378 // aligned within this target area according to the specified alignment |
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379 // instruction. |
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380 // If the length of the target area is larger than the length of the source, then |
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381 // spare space within the target area is padded with the fill character. |
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382 // This leaving variant of the standard, non-leaving descriptor method |
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383 // differs in that this operation may cause the string descriptor's heap |
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384 // buffer to be reallocated in order to accommodate the new data. As a |
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385 // result, MaxLength() and Ptr() may return different values afterwards, |
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386 // and any existing raw pointers to into the descriptor data may be |
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387 // invalidated. |
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388 s.CopyL(L"Justified"); |
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389 s.JustifyL(L"Just",9,ERight,'x'); |
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390 test(s == L"xxxxxJust"); |
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391 |
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392 // Append data onto the end of this descriptor's data and justifies it. |
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393 // The source of the appended data is a memory location. |
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394 // The target area is considered to be an area of specified width, immediately |
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395 // following this descriptor's existing data. Source data is copied into, and |
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396 // aligned within, this target area according to the specified alignment instruction. |
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397 // If the length of the target area is larger than the length of the source, |
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398 // then spare space within the target area is padded with the fill character. |
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399 // This leaving variant of the standard, non-leaving descriptor method |
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400 // differs in that this operation may cause the string descriptor's heap |
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401 // buffer to be reallocated in order to accommodate the new data. As a |
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402 // result, MaxLength() and Ptr() may return different values afterwards, |
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403 // and any existing raw pointers to into the descriptor data may be |
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404 // invalidated. |
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405 s.CopyL(L"One "); |
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406 s.AppendJustifyL(L"Two Three",3,7,ERight,'x'); |
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407 test(s == L"One xxxxTwo" ); |
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408 |
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409 } |
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410 { |
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411 // You can initialize with a MaxLength value |
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412 LString s(KMaxFileName); // This operation may leave |
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413 test(s.MaxLength() == KMaxFileName); |
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414 |
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415 // And you can dynamically adjust MaxLength later using |
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416 // SetMaxLengthL if you want an exact allocated size |
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417 // Setting MaxLength on construction or via SetMaxLengthL is |
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418 // exact; calling MaxLength() immediately afterwards is |
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419 // guaranteed to return exactly the value you specified |
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420 s.SetMaxLengthL(2 * KMaxFileName); |
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421 test(s.MaxLength() == 2 * KMaxFileName); |
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422 |
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423 // Pre-setting MaxLength is important when passing an LString |
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424 // as a TDes to a library function, because the LString can't |
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425 // be auto-grown via the TDes API |
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426 |
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427 } |
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428 |
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429 { |
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430 // You can initialize from any descriptor/literal/[wide]character string and the |
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431 // string data is copied into the LString |
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432 LString s(L"One "); // From a character string |
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433 s += L"Two "; |
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434 LString half(s.Left(s.Length() / 2)); // Left returns a TPtrC |
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435 test.Printf(_L("All: %S, Half: %S\n"), &s, &half); |
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436 |
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437 // On the other hand, you can initialize from a returned |
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438 // HBufC* and the LString automatically takes ownership |
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439 LString own(AllocateNameL(KTesting)); |
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440 test.Printf(_L("What I own: %S\n"), &own); |
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441 |
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442 // Following that you can re-assign an HBufC to an existing |
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443 // string using the assignment operator |
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444 // taking ownership of the new content. |
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445 own = AllocateNameL(KTesting); |
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446 |
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447 // Following that you can re-assign an HBufC to an existing |
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448 // string. The string destroys its original content before |
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449 // taking ownership of the new content. |
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450 own.Assign(AllocateNameL(KTesting)); |
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451 |
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452 // The content of one string can similarly be assigned |
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453 // to another to avoid copying. In this example, the content |
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454 // is detached from 's' and transfered to 'own'. |
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455 own.Assign(s); |
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456 |
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457 // The same content transfer can be achieved from an RBuf to a |
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458 // string. You may need to do this if a legacy method returns |
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459 // you an RBuf. The RBuf is emptied of its content. |
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460 RBuf16 buf; |
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461 buf.CreateL(KOne); |
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462 own.Assign(buf); |
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463 |
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464 // You can also assign a simple text array to a string as its |
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465 // new buffer. This method initialises the length to zero. |
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466 own.Assign((TText*)User::Alloc(24*(TInt)sizeof(TText)), 24); |
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467 |
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468 // If the buffer has already been filled with some characters |
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469 // then you supply the length in this alternative Assign method. |
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470 own.Assign((TText*)User::Alloc(24*(TInt)sizeof(TText)), 12,24); |
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471 |
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472 // Each Assign destroys the old content before assuming ownership |
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473 // of the new. |
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474 // As usual the last content of the string is destroyed when the |
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475 // LString goes out of scope |
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476 } |
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477 |
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478 { |
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479 // You can reserve extra free space in preparation for an |
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480 // operation that adds characters to the string. You may |
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481 // need to do this when you cannot use any of the auto-buffer |
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482 // extending LString methods to achieve your objective. |
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483 LString s(L"One "); |
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484 s.ReserveFreeCapacityL(4); |
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485 test(s.Length() == 4); |
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486 test(s.MaxLength() >= 8); |
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487 |
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488 // Almost all the methods that may extended the string buffer, |
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489 // including the explicit ReserveFreeCapacityL, but excluding |
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490 // SetMaxLengthL, attempt to grow the size exponentially. |
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491 // The Exponential growth pattern is expected to give better |
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492 // performance at an amortised complexity of O(n) when adding n characters. |
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493 // If the exponential growth is less than the supplied extra size |
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494 // then the supplied size is used instead to save time. |
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495 // The exponential growth is used in anticipation of further additions |
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496 // to a string. This trades-off speed efficiency for space efficiency. |
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497 // If required you may be able to swap the oversized buffer for |
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498 // a more compact one using: |
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499 s.Compress(); |
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500 test(s.MaxLength() >= 4); //note indefinite test |
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501 |
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502 // Resize attempts to re-allocate a smaller buffer to copy |
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503 // the content into. If the new memory cannot be allocated then the |
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504 // original string is left unaffected. |
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505 |
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506 // When you have finished using the content of a string you can |
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507 // get its buffer released without destroying the string itself. |
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508 // You may want to do this when using member declared strings. |
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509 // Automatic strings are destroyed when they go out of scope. |
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510 s.Reset(); |
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511 test(s.Length() == 0); |
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512 test(s.MaxLength() == 0); |
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513 |
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514 } |
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515 |
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516 { |
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517 // An LString can be passed directly to any function requiring |
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518 // a const TDesC& |
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519 TInt year = 2009; |
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520 |
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521 LString s; |
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522 s.FormatL(_L("Happy New Year %d"), year); |
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523 // InfoPrint takes a const TDesC& |
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524 User::InfoPrint(s); |
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525 |
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526 LString pattern; |
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527 pattern.FormatL(_L("*Year %d"), year); |
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528 // Match takes a const TDesC& as a pattern |
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529 TInt loc = s.Match(pattern); |
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530 test(loc == 10); |
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531 } |
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532 |
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533 { |
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534 // An LString can be passed directly to any function requiring |
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535 // a TDes& but care must always be taken to pre-set MaxLength |
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536 // since LStrings can't be automatically grown via the TDes |
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537 // interface |
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538 |
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539 LString s; |
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540 // Calling GetCurrentPath(s) now would panic because LStrings |
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541 // are initialized by default to MaxLength 0. Although s is |
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542 // an LString GetCurrentPath takes a TDes& and so inside the function |
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543 // s behaves as a TDes and would panic with USER 11 if the resulting |
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544 // new length of s is greater than its maximum length. |
|
545 test(s.MaxLength() == 0); |
|
546 |
|
547 // Calling SetMaxLengthL will automatically realloc the |
|
548 // underlying buffer if required, and is guaranteed to leave |
|
549 // MaxLength() equal to the specified value |
|
550 s.SetMaxLengthL(KMaxFileName); |
|
551 GetCurrentPath(s); |
|
552 //LString pathString(L"c:\\a\\b\\c"); |
|
553 test.Printf(_L("Path: %S\n"), &s); |
|
554 test(s == L"c:\\a\\b\\c"); |
|
555 |
|
556 // If SetMaxLengthL adjusts MaxLength lower than the current |
|
557 // Length, the data is truncated to the new MaxLength and |
|
558 // Length set to the new MaxLength |
|
559 s.SetMaxLengthL(s.Length() / 2); |
|
560 test.Printf(_L("Truncated path: %S\n"), &s); |
|
561 test(s.Length() == s.MaxLength()); |
|
562 |
|
563 // An initial MaxLength can be specified when constructing an |
|
564 // LString. Note that unlike the default constructor, this |
|
565 // variant allocates and may leave. |
|
566 LString s2(KMaxFileName); |
|
567 GetCurrentPath(s2); |
|
568 test.Printf(_L("Path: %S\n"), &s2); |
|
569 test(s2 == L"c:\\a\\b\\c"); |
|
570 |
|
571 // Your code and APIs can benefit from LString's auto-growth |
|
572 // behaviour by accepting an LString to fill in as an output |
|
573 // parameter. Using LString rather than TDes parameters means |
|
574 // that the function is able to safely increase the size of the |
|
575 // string as the LString will re-allocate as necessary |
|
576 LString s3; |
|
577 // GetCurrentPathStringL takes an LString& |
|
578 GetCurrentPathStringL(s3); |
|
579 test.Printf(_L("Path: %S\n"), &s3); |
|
580 test(s3 == L"c:\\a\\b\\c"); |
|
581 |
|
582 // As a well-defined value class, if you want to, LStrings can |
|
583 // be passed and returned by value. This is relatively |
|
584 // inefficient however due to the amount of copying and heap |
|
585 // reallocation involved. |
|
586 LString s4(AppendCurrentPathStringL(s3)); |
|
587 test.Printf(_L("Appended path: %S\n"), &s4); |
|
588 test(s4.Length() == s3.Length() * 2); |
|
589 } |
|
590 |
|
591 { |
|
592 // LStrings can be allocated on the heap if necessary. |
|
593 // Then it can managed as part of an array of string pointers |
|
594 TInt n = 5; |
|
595 LCleanedupHandle<RPointerArray<LString>, TResetAndDestroy> sarray; |
|
596 |
|
597 for (TInt i = 0; i < n; ++i) |
|
598 { |
|
599 LString* s = new(ELeave) LString; |
|
600 s->FormatL(_L("String %d"), i); |
|
601 sarray->Append(s); |
|
602 } |
|
603 |
|
604 for (TInt i = 0, n = sarray->Count(); i < n; ++i) |
|
605 { |
|
606 LString tmp; |
|
607 tmp.FormatL(_L("String %d"), i); |
|
608 test(tmp == *(*sarray)[i]); |
|
609 test.Printf(_L("String %d = %S\n"), i, (*sarray)[i]); |
|
610 } |
|
611 |
|
612 } |
|
613 |
|
614 { |
|
615 // Any allocation failure in new(ELeave)LString throws |
|
616 // KErrNoMemory and cleans up after itself fully |
|
617 |
|
618 __UHEAP_MARK; |
|
619 //coverity[resource_leak] |
|
620 //As mentioned in the comment above any allocation failure is taken care of |
|
621 TRAPD(status, new(ELeave) LString(100 * 1024 * 1024)); |
|
622 test(status == KErrNoMemory); |
|
623 __UHEAP_MARKEND; |
|
624 } |
|
625 |
|
626 { |
|
627 // Native C arrays (both heap and stack allocated) of LStrings |
|
628 // also work, although their use is not recommended |
|
629 |
|
630 TInt n = 5; |
|
631 LCleanedupArray<LString> sarray(new(ELeave) LString[n]); |
|
632 |
|
633 for (TInt i = 0; i < n; ++i) |
|
634 { |
|
635 sarray[i].FormatL(_L("String %d"), i); |
|
636 } |
|
637 |
|
638 for (TInt i = 0; i < n; ++i) |
|
639 { |
|
640 LString tmp; |
|
641 tmp.FormatL(_L("String %d"), i); |
|
642 test(tmp == sarray[i]); |
|
643 test.Printf(_L("String %d = %S\n"), i, &sarray[i]); |
|
644 } |
|
645 |
|
646 } |
|
647 { |
|
648 // 8-bit wide null terminated character string support |
|
649 |
|
650 // A default constructed LString8 starts empty, doesn't |
|
651 // allocate any memory on the heap, and therefore the |
|
652 // following cannot leave |
|
653 LString8 s; |
|
654 |
|
655 // But it will grow on demand if you assign to it, so it has |
|
656 // enough space to hold the copied string data, and so |
|
657 // assignment may leave |
|
658 s ="One "; |
|
659 |
|
660 // Similarly if you append to it with the leaving variant of |
|
661 // Append, AppendL, if may grow on demand |
|
662 s.AppendL("Two "); |
|
663 |
|
664 // The += operator for LString8 also maps to AppendL |
|
665 s +="Three "; |
|
666 s +="Testing "; |
|
667 |
|
668 // An LString8 can be printed the same way as any descriptor |
|
669 test.Printf(_L("Value: %S \n"), &s); |
|
670 |
|
671 // An LString8 can be compared the same way as any descriptor |
|
672 test(s == "One Two Three Testing "); |
|
673 |
|
674 // An LString8 supports all TDesC and TDes methods |
|
675 // LString findToken("Two "); |
|
676 test(s.Find("Two ") == 4); |
|
677 |
|
678 // LString8 matchPattern("*Two* "); |
|
679 test(s.Match("*Two*") == 4); |
|
680 test(s.Match("*T?o*") == 4); |
|
681 |
|
682 // LString8 compare("some string"); |
|
683 test(s.Compare("One Two Three Testing ") == 0); |
|
684 test(s.Compare("One Two Three Testing! ") < 0); |
|
685 test(s.Compare("One Two Testing ") > 0); |
|
686 |
|
687 // also LString8 ==,!=,>,<,<=,>=(L"some string"); |
|
688 test(s == "One Two Three Testing "); |
|
689 test(s < "One Two Three Testing! "); |
|
690 test(s > "One Two Testing "); |
|
691 test(s != "not equal"); |
|
692 |
|
693 // Copies data into this 8-bit string descriptor, replacing any existing |
|
694 // data, and expanding its heap buffer to accommodate if necessary. |
|
695 // leaves on not being able to accomodate the new content |
|
696 // both AssignL and += use CopyL internally |
|
697 s.CopyL("new way of dealing with strings"); |
|
698 |
|
699 |
|
700 // Copy, Append,Insert,Replace,Justify the same way as TDesC8 and TDes8 |
|
701 |
|
702 // Copies data into this 8-bit string descriptor, replacing any existing |
|
703 // data, and expanding its heap buffer to accommodate if necessary. |
|
704 // leaves on not being able to accomodate the new content |
|
705 // both AssignL and += use CopyL internally |
|
706 s.CopyL("new way of dealing with strings"); |
|
707 s.CopyUCL("new way of dealing with strings"); |
|
708 test(s == "NEW WAY OF DEALING WITH STRINGS"); |
|
709 |
|
710 // Insert data into this descriptor. |
|
711 // The length of this descriptor is changed to reflect the extra data. |
|
712 // This leaving variant of the standard, non-leaving descriptor method |
|
713 // differs in that this operation may cause the string descriptor's heap |
|
714 // buffer to be reallocated in order to accommodate the new data. As a |
|
715 // result, MaxLength() and Ptr() may return different values afterwards, |
|
716 // and any existing raw pointers to into the descriptor data may be |
|
717 // invalidated. |
|
718 s.CopyL("Some Content Can Be Into This String"); |
|
719 s.InsertL(20,"Inserted "); |
|
720 test(s == "Some Content Can Be Inserted Into This String"); |
|
721 |
|
722 // Replace data in this descriptor. |
|
723 // The specified length can be different to the length of the replacement data. |
|
724 // The length of this descriptor changes to reflect the change of data. |
|
725 // This leaving variant of the standard, non-leaving descriptor method |
|
726 // differs in that this operation may cause the string descriptor's heap |
|
727 // buffer to be reallocated in order to accommodate the new data. As a |
|
728 // result, MaxLength() and Ptr() may return different values afterwards, |
|
729 // and any existing raw pointers to into the descriptor data may be |
|
730 // invalidated. |
|
731 s.CopyL("Some Content Can Be Decalper"); |
|
732 s.ReplaceL(20,8,"Replaced"); |
|
733 test(s == "Some Content Can Be Replaced"); |
|
734 |
|
735 // Append data onto the end of this descriptor's data. |
|
736 // The length of this descriptor is incremented to reflect the new content. |
|
737 // This leaving variant of the standard, non-leaving descriptor method |
|
738 // differs in that this operation may cause the string descriptor's heap |
|
739 // buffer to be reallocated in order to accommodate the new data. As a |
|
740 // result, MaxLength() and Ptr() may return different values afterwards, |
|
741 // and any existing raw pointers to into the descriptor data may be |
|
742 // invalidated. |
|
743 s.CopyL("Try appending "); |
|
744 s.AppendL("Try appending some more",3); |
|
745 test(s == "Try appending Try"); |
|
746 |
|
747 // Copy data into this descriptor and justifies it, replacing any existing data. |
|
748 // The length of this descriptor is set to reflect the new data. |
|
749 // The target area is considered to be an area of specified width positioned at |
|
750 // the beginning of this descriptor's data area. Source data is copied into, and |
|
751 // aligned within this target area according to the specified alignment |
|
752 // instruction. |
|
753 // If the length of the target area is larger than the length of the source, then |
|
754 // spare space within the target area is padded with the fill character. |
|
755 // This leaving variant of the standard, non-leaving descriptor method |
|
756 // differs in that this operation may cause the string descriptor's heap |
|
757 // buffer to be reallocated in order to accommodate the new data. As a |
|
758 // result, MaxLength() and Ptr() may return different values afterwards, |
|
759 // and any existing raw pointers to into the descriptor data may be |
|
760 // invalidated. |
|
761 s.CopyL("Justified"); |
|
762 s.JustifyL("Just",9,ERight,'x'); |
|
763 test(s == "xxxxxJust"); |
|
764 |
|
765 // Append data onto the end of this descriptor's data and justifies it. |
|
766 // The source of the appended data is a memory location. |
|
767 // The target area is considered to be an area of specified width, immediately |
|
768 // following this descriptor's existing data. Source data is copied into, and |
|
769 // aligned within, this target area according to the specified alignment instruction. |
|
770 // If the length of the target area is larger than the length of the source, |
|
771 // then spare space within the target area is padded with the fill character. |
|
772 // This leaving variant of the standard, non-leaving descriptor method |
|
773 // differs in that this operation may cause the string descriptor's heap |
|
774 // buffer to be reallocated in order to accommodate the new data. As a |
|
775 // result, MaxLength() and Ptr() may return different values afterwards, |
|
776 // and any existing raw pointers to into the descriptor data may be |
|
777 // invalidated. |
|
778 s.CopyL("One "); |
|
779 s.AppendJustifyL("Two Three",3,7,ERight,'x'); |
|
780 test(s == "One xxxxTwo" ); |
|
781 |
|
782 } |
|
783 |
|
784 } |
|
785 |
|
786 // This class demonstrates the use of the embeddable management |
|
787 // classes in a conventional Symbian two-phase construction |
|
788 // pattern. |
|
789 class CManagedUserTwoPhase : public CBase |
|
790 { |
|
791 public: |
|
792 static CManagedUserTwoPhase* NewL(CTicker* aTicker) |
|
793 { |
|
794 // We can use the resource management utility classes in |
|
795 // two-phase if we want to |
|
796 LCleanedupPtr<CManagedUserTwoPhase> self(new(ELeave) CManagedUserTwoPhase); |
|
797 self->ConstructL(aTicker); |
|
798 // Calling Unmanage() disables cleanup and yields the |
|
799 // previously managed pointer so that it can be safely |
|
800 // returned |
|
801 return self.Unmanage(); |
|
802 } |
|
803 |
|
804 ~CManagedUserTwoPhase() |
|
805 { |
|
806 // The iTicker manager will automatically delete the CTicker |
|
807 // The iTimer manager will automatically Close() the RTimer |
|
808 } |
|
809 |
|
810 CTicker& Ticker() |
|
811 { |
|
812 // If we dereference the management object we get a CTicker& |
|
813 return *iTicker; |
|
814 } |
|
815 |
|
816 RTimer& Timer() |
|
817 { |
|
818 // If we dereference the management object we get an RTimer& |
|
819 return *iTimer; |
|
820 } |
|
821 |
|
822 private: |
|
823 |
|
824 virtual void ConstructL(CTicker* aTicker) |
|
825 { |
|
826 // Take ownership and manage aTicker |
|
827 iTicker = aTicker; |
|
828 |
|
829 // Note use of -> to indirect through the management wrapper |
|
830 iTimer->CreateLocal() OR_LEAVE; |
|
831 } |
|
832 |
|
833 CManagedUserTwoPhase() |
|
834 { |
|
835 // Everything interesting happens in ConstructL in this |
|
836 // version. |
|
837 |
|
838 // Default initialization of the iName LString does not |
|
839 // allocate a heap buffer, and so cannot leave. As long as |
|
840 // initialization is deferred to ConstructL, LStrings can be |
|
841 // used safely with two-phase construction. |
|
842 } |
|
843 |
|
844 private: |
|
845 // We have to use LManagedXxx for fields, not LCleanedupXxx |
|
846 LManagedPtr<CTicker> iTicker; |
|
847 LManagedHandle<RTimer> iTimer; |
|
848 }; |
|
849 |
|
850 // This class demonstrates the use of embedded management classes in |
|
851 // the single-phase construction pattern, where a leave-safe |
|
852 // constructor fully initializes the object. |
|
853 // |
|
854 // Note that where a class's constructor forms part of its exported |
|
855 // public or protected contract, switching from a non-leaving to a |
|
856 // potentially leaving constructor would be a BC break. On the other |
|
857 // hand, if instantiation is entirely encapsulated within factory |
|
858 // functions like NewL, there is no such BC restriction. |
|
859 |
|
860 class CManagedUserSinglePhase : public CBase |
|
861 { |
|
862 public: |
|
863 // This macro is necessary to ensure cleanup is correctly handled |
|
864 // in the event that a constructor may leave beneath a call to |
|
865 // new(ELeave) |
|
866 CONSTRUCTORS_MAY_LEAVE |
|
867 |
|
868 static CManagedUserSinglePhase* NewL(CTicker* aTicker) |
|
869 { |
|
870 return new(ELeave) CManagedUserSinglePhase(aTicker); |
|
871 } |
|
872 |
|
873 ~CManagedUserSinglePhase() |
|
874 { |
|
875 // The iTicker manager destructor will automatically Zap() the CTicker |
|
876 // The iTimer manager destructor will automatically Close() the RTimer |
|
877 } |
|
878 |
|
879 CTicker& Ticker() |
|
880 { |
|
881 // If we dereference the management object we get a CTicker& |
|
882 return *iTicker; |
|
883 } |
|
884 |
|
885 RTimer& Timer() |
|
886 { |
|
887 // If we dereference the management object we get an RTimer& |
|
888 return *iTimer; |
|
889 } |
|
890 |
|
891 private: |
|
892 CManagedUserSinglePhase(CTicker* aTicker) |
|
893 // Take ownership and manage aTicker. Note that initialization |
|
894 // of the LManagedXxx classes does not actually leave, but |
|
895 // initialization of the LCleanedupXxx classes can. |
|
896 : iTicker(aTicker) |
|
897 { |
|
898 // If iTicker initialization is successful but the constructor |
|
899 // then goes on to leave later, iTicker (like all fields fully |
|
900 // constructed at the point of a leave in a constructor) will |
|
901 // be destructed, and the manager will cleanup the CTicker |
|
902 |
|
903 // Note use of -> to indirect through the management wrapper |
|
904 iTimer->CreateLocal() OR_LEAVE; |
|
905 |
|
906 // Likewise if we leave here, both iTicker and iTimer will |
|
907 // undergo managed cleanup |
|
908 MaybeLeaveL(); |
|
909 } |
|
910 |
|
911 private: |
|
912 // We have to use LManagedXxx for fields, not LCleanedupXxx |
|
913 LManagedPtr<CTicker, TTickerZapStrategy> iTicker; |
|
914 LManagedHandle<RTimer> iTimer; |
|
915 }; |
|
916 |
|
917 //Class definition of trivial R-Class |
|
918 class RSimple |
|
919 { |
|
920 public: |
|
921 |
|
922 RSimple(){iData = NULL;} |
|
923 |
|
924 //Open function sets value |
|
925 void OpenL(TInt aValue) |
|
926 { |
|
927 iData = new(ELeave) TInt(aValue); |
|
928 } |
|
929 |
|
930 //Cleanup function – frees resource |
|
931 void Close() |
|
932 { |
|
933 delete iData; |
|
934 iData = NULL; |
|
935 } |
|
936 |
|
937 //Cleanup function – frees resource |
|
938 void Free() |
|
939 { |
|
940 delete iData; |
|
941 iData = NULL; |
|
942 } |
|
943 |
|
944 //Cleanup function – frees resource |
|
945 void ReleaseData() |
|
946 { |
|
947 delete iData; |
|
948 iData = NULL; |
|
949 } |
|
950 |
|
951 //static cleanup function – frees aRSimple resources |
|
952 static void Cleanup(TAny* aRSimple) |
|
953 { |
|
954 static_cast<RSimple*>(aRSimple)->Close(); |
|
955 } |
|
956 |
|
957 |
|
958 private: |
|
959 TInt* iData; |
|
960 |
|
961 }; |
|
962 |
|
963 |
|
964 //This sets the default cleanup behaviour for the RSimple class to |
|
965 //be RSimple::ReleaseData. |
|
966 //If this Macro is not used then the default cleanup behaviour |
|
967 //would be to call RSimple::Close(). |
|
968 DEFINE_CLEANUP_FUNCTION(RSimple, ReleaseData); |
|
969 |
|
970 |
|
971 void WalkthroughManagedL() |
|
972 { |
|
973 { |
|
974 // Trivially exercise the manager-using classes defined above |
|
975 CTicker* ticker1 = new(ELeave) CTicker; |
|
976 LCleanedupPtr<CManagedUserTwoPhase> one(CManagedUserTwoPhase::NewL(ticker1)); |
|
977 test(&one->Ticker() == ticker1); |
|
978 one->Timer().Cancel(); // Just to check we can get at it |
|
979 |
|
980 CTicker* ticker2 = new(ELeave) CTicker; |
|
981 LCleanedupPtr<CManagedUserSinglePhase> two(CManagedUserSinglePhase::NewL(ticker2)); |
|
982 test(&two->Ticker() == ticker2); |
|
983 two->Timer().Cancel(); // Just to check we can get at it |
|
984 |
|
985 // Both instances are automatically deleted as we go out of scope |
|
986 } |
|
987 |
|
988 // Always use LCleanedupXxx for locals, not LManagedXxx |
|
989 |
|
990 { |
|
991 // Begin the scenes the LCleanedupXxx constructors push a |
|
992 // cleanup item onto the cleanup stack and so may leave. If |
|
993 // there is a leave during construction, the supplied pointer |
|
994 // will still get cleaned up. |
|
995 LCleanedupPtr<CTicker> t(new(ELeave) CTicker); |
|
996 |
|
997 // We can access CTicker's members via the management object |
|
998 // using -> |
|
999 t->Tick(); |
|
1000 t->Tock(); |
|
1001 test(t->iTicks == t->iTocks); |
|
1002 |
|
1003 // We can get at a reference to the managed object using * |
|
1004 // when we need to, e.g. if we need to pass it to a function |
|
1005 RegisterTicker(*t); // Takes a CTicker& |
|
1006 |
|
1007 // If some unfriendly interface needs a pointer rather than a |
|
1008 // ref, we have a couple of options |
|
1009 RegisterTickerPtr(&*t); // Takes a CTicker* |
|
1010 RegisterTickerPtr(t.Get()); // Takes a CTicker* |
|
1011 |
|
1012 // Note the use of . in t.Get() above; this distinguishes |
|
1013 // operations on the managing type from operations on the |
|
1014 // managed object |
|
1015 |
|
1016 // When the management object goes out of scope, either |
|
1017 // normally or as the result of a leave, the managed object is |
|
1018 // automatically deleted |
|
1019 } |
|
1020 |
|
1021 { |
|
1022 // Sometimes you need to protect something temporarily before |
|
1023 // transferring ownership e.g. by returning the pointer or |
|
1024 // passing it to a function that takes ownership. |
|
1025 |
|
1026 LCleanedupPtr<CTicker> t(new(ELeave) CTicker); |
|
1027 |
|
1028 // Protected while we do this |
|
1029 MaybeLeaveL(); |
|
1030 |
|
1031 // But now we want to hand it off, so we use Unmanage() to |
|
1032 // both return a pointer and break the management link |
|
1033 TakeTickerOwnership(t.Unmanage()); |
|
1034 |
|
1035 // Now when it goes out of scope, no cleanup action is |
|
1036 // performed |
|
1037 } |
|
1038 |
|
1039 { |
|
1040 // If needed, it is possible to reuse a manager by using = to |
|
1041 // assign it a new managed object. |
|
1042 |
|
1043 // Not managing anything to start with |
|
1044 LCleanedupPtr<CTicker> t; |
|
1045 test(t.Get() == NULL); |
|
1046 test(&*t == NULL); |
|
1047 |
|
1048 for (TInt i = 0; i < 10; ++i) |
|
1049 { |
|
1050 // If an object is already being managed, it is cleaned up |
|
1051 // before taking ownership of the new object |
|
1052 t = new(ELeave) CTicker; |
|
1053 } |
|
1054 // We're left owning the final ticker instance, all prior |
|
1055 // instances having been automatically deleted |
|
1056 } |
|
1057 |
|
1058 { |
|
1059 // If you have stateful code where a pointer can sometimes be |
|
1060 // NULL, as a convenience you can test the managing object |
|
1061 // itself as a shortcut test for NULL |
|
1062 LCleanedupPtr<CTicker> t(new(ELeave) CTicker); |
|
1063 |
|
1064 // Does t refer to NULL? |
|
1065 if (!t) |
|
1066 { |
|
1067 test(EFalse); |
|
1068 } |
|
1069 |
|
1070 t = NULL; // Also releases the currently managed CTicker |
|
1071 |
|
1072 // Does t refer to a non-NULL pointer? |
|
1073 if (t) |
|
1074 { |
|
1075 test(EFalse); |
|
1076 } |
|
1077 } |
|
1078 |
|
1079 { |
|
1080 // LCleanedupPtr uses delete to cleanup by default, but |
|
1081 // alternative cleanups can be specified |
|
1082 |
|
1083 // We just want to free this one and not invoke the destructor |
|
1084 LCleanedupPtr<CTicker, TPointerFree> t(static_cast<CTicker*>(User::AllocL(sizeof(CTicker)))); |
|
1085 |
|
1086 // Now User::Free() is called when t goes out of scope |
|
1087 } |
|
1088 |
|
1089 { |
|
1090 // As well as the stock options, custom cleanup policies can |
|
1091 // also be defined. See above for the definition of |
|
1092 // TTickerZap. |
|
1093 LCleanedupPtr<CTicker, TTickerZapStrategy> t(new(ELeave) CTicker); |
|
1094 |
|
1095 // Now Zap() is called on the CTicker instance when t goes out of scope |
|
1096 } |
|
1097 |
|
1098 { |
|
1099 // LCleanedupHandle is very similar in behaviour to |
|
1100 // LCleanedupPtr, the main difference being that it can define |
|
1101 // and contain its own instance of a handle rather than |
|
1102 // being supplied one |
|
1103 LCleanedupHandle<RTimer> t; |
|
1104 |
|
1105 // Again, access to managed handle members is via -> |
|
1106 t->CreateLocal() OR_LEAVE; |
|
1107 t->Cancel(); |
|
1108 |
|
1109 // We can get a reference to the handle for passing to |
|
1110 // functions using * |
|
1111 RegisterTimer(*t); |
|
1112 |
|
1113 // When the management object goes out of scope, either |
|
1114 // normally or as the result of a leave, the managed object is |
|
1115 // automatically cleanup by calling Close() on it |
|
1116 } |
|
1117 |
|
1118 { |
|
1119 // LCleanedupHandle calls Close() by default, but alternative |
|
1120 // cleanups can be specified |
|
1121 |
|
1122 // We want this RPointerArray cleanup with with |
|
1123 // ResetAndDestroy instead of Close() |
|
1124 LCleanedupHandle<RPointerArray<HBufC>, TResetAndDestroy> array; |
|
1125 for (TInt i = 0; i < 10; ++i) |
|
1126 { |
|
1127 array->AppendL(HBufC::NewL(5)); |
|
1128 } |
|
1129 |
|
1130 // Now when array goes out of scope, ResetAndDestroy is called |
|
1131 // to clean it up |
|
1132 } |
|
1133 |
|
1134 { |
|
1135 // As well as the stock options, custom cleanup policies can |
|
1136 // also be defined. See above for the definition of |
|
1137 // TCancelClose. |
|
1138 LCleanedupHandle<RTimer, TCancelClose> t; |
|
1139 t->CreateLocal(); |
|
1140 |
|
1141 // Now Cancel() followed by Close() are called when t goes out |
|
1142 // of scope |
|
1143 } |
|
1144 |
|
1145 |
|
1146 { |
|
1147 // LCleanedupHandleRef calls Close() by default, but alternative |
|
1148 // cleanups can be specified |
|
1149 |
|
1150 // We want this RPointerArray cleanup with with |
|
1151 // ResetAndDestroy instead of Close() |
|
1152 RPointerArray<HBufC> rar; |
|
1153 // calls to functions that cannot leave here |
|
1154 rar.Append(HBufC::NewL(5)); |
|
1155 rar.Append(HBufC::NewL(5)); |
|
1156 |
|
1157 |
|
1158 LCleanedupRef<RPointerArray<HBufC>, TResetAndDestroy> array(rar); |
|
1159 // calls to functions that could leave here |
|
1160 for (TInt i = 0; i < 10; ++i) |
|
1161 { |
|
1162 array->AppendL(HBufC::NewL(5)); |
|
1163 } |
|
1164 |
|
1165 // Now when array goes out of scope, ResetAndDestroy is called |
|
1166 // to clean it up |
|
1167 } |
|
1168 |
|
1169 { |
|
1170 // Never mix direct cleanup stack API calls with management |
|
1171 // class use within the same function, because their |
|
1172 // interaction can be confusing and counter intuitive. Avoid |
|
1173 // the use of LC methods that leave objects on the cleanup |
|
1174 // stack, and use L methods instead. |
|
1175 |
|
1176 // If a badly-behaved API were to offer only an LC variant, |
|
1177 // you would have to use it as follows |
|
1178 HBufC* raw = HBufC::NewLC(5); |
|
1179 // Must pop immediately to balance the cleanup stack, before |
|
1180 // instantiating the manager |
|
1181 CleanupStack::Pop(); |
|
1182 LCleanedupPtr<HBufC> wrapped(raw); |
|
1183 |
|
1184 // Never do this: |
|
1185 //LCleanedupPtr<HBufC> buf(HBufC::NewLC(5)); |
|
1186 //CleanupStack::Pop(); |
|
1187 // because the manager will be popped (having been pushed |
|
1188 // last), not the raw buf pointer as you might have hoped |
|
1189 |
|
1190 // A cleaner alternative may be to write your own L function |
|
1191 // wrapper around the LC function supplied. |
|
1192 |
|
1193 // Luckily this situation (an LC method without a |
|
1194 // corresponding L method) is rare in practice. |
|
1195 } |
|
1196 |
|
1197 { |
|
1198 // Although rarely used on Symbian OS, C++ arrays are |
|
1199 // supported with a custom management class |
|
1200 LCleanedupArray<CTicker> array(new CTicker[5]); |
|
1201 |
|
1202 // The array is cleaned up with delete[] on scope exit |
|
1203 } |
|
1204 |
|
1205 { |
|
1206 // Although most cases are best covered by applying custom |
|
1207 // cleanup policies to the management classes already |
|
1208 // described, there is also a general TCleanupItem style |
|
1209 // cleanup option |
|
1210 TAny* data = NULL; // But could be anything |
|
1211 LCleanedupGuard guard1(BespokeCleanupFunction, data); |
|
1212 // On scope exit BespokeCleanupFunction is called on data |
|
1213 |
|
1214 LCleanedupGuard guard2(BespokeCleanupFunction, data); |
|
1215 // But cleanup can also be disabled in this case, as follows |
|
1216 guard2.Dismiss(); |
|
1217 } |
|
1218 |
|
1219 { |
|
1220 LCleanedupHandle<RFs> managedFs; |
|
1221 managedFs->Connect(); |
|
1222 //default cleanup strategy is to call RFs::Close() on scope exit |
|
1223 } |
|
1224 |
|
1225 { |
|
1226 LCleanedupHandle<RSimple, TFree> simple; |
|
1227 simple->OpenL(23); |
|
1228 //Specified cleanup strategy is to call RSimple::Free() on scope exit |
|
1229 } |
|
1230 |
|
1231 //Because the DEFINE_CLEANUP_FUNCTION is defined above, the default |
|
1232 //cleanup function for RSimple is RSimple::ReleaseData() rather than |
|
1233 //RSimple::Close() |
|
1234 { |
|
1235 LCleanedupHandle<RSimple> simple; |
|
1236 simple->OpenL(23); |
|
1237 //Custom cleanup strategy is to call RSimple::ReleaseData() on scope exit |
|
1238 } |
|
1239 |
|
1240 { |
|
1241 RSimple simple; |
|
1242 |
|
1243 //The RSimple class above defines a static cleanup function |
|
1244 //RSimple::Cleanup. |
|
1245 LCleanedupGuard guard(RSimple::Cleanup, &simple); |
|
1246 |
|
1247 simple.OpenL(10); |
|
1248 |
|
1249 //On scope exit RSimple::Cleanup() is called passing &simple |
|
1250 } |
|
1251 } |
|
1252 |
|
1253 void WalkthroughUsageL() |
|
1254 { |
|
1255 RFile file; |
|
1256 |
|
1257 test.Printf(_L("Size of RFile = %d"), sizeof(file)); |
|
1258 |
|
1259 LCleanedupHandle<RFile> cFile; |
|
1260 |
|
1261 test.Printf(_L("Size of LCleanedupHandle<RFile> = %d"), sizeof(cFile)); |
|
1262 |
|
1263 LCleanedupRef<RFile> crFile(file); |
|
1264 |
|
1265 test.Printf(_L("Size of LCleanedupRef<RFile> = %d"), sizeof(crFile)); |
|
1266 |
|
1267 CTicker* tracker = new(ELeave) CTicker; |
|
1268 //coverity[resource_leak] |
|
1269 //As mentioned in the comment above any allocation failure is taken care of |
|
1270 test.Printf(_L("Size of CTracker* = %d"), sizeof(tracker)); |
|
1271 |
|
1272 LCleanedupPtr<CTicker> cTracker(tracker); |
|
1273 |
|
1274 test.Printf(_L("Size of LCleanedupHandle<RFile> = %d"), sizeof(LCleanedupPtr<CTicker>)); |
|
1275 } |
|
1276 |
|
1277 TInt TestL() |
|
1278 { |
|
1279 WalkthroughStringsL(); |
|
1280 WalkthroughManagedL(); |
|
1281 WalkthroughUsageL(); |
|
1282 |
|
1283 return KErrNone; |
|
1284 } |
|
1285 |
|
1286 TInt E32Main() |
|
1287 { |
|
1288 |
|
1289 test.Start(_L("EUserHl Walkthrough")); |
|
1290 test.Title(); |
|
1291 |
|
1292 CTrapCleanup* trapHandler=CTrapCleanup::New(); |
|
1293 test(trapHandler!=NULL); |
|
1294 |
|
1295 __UHEAP_MARK; |
|
1296 |
|
1297 TRAPD(status, TestL()); |
|
1298 |
|
1299 __UHEAP_MARKEND; |
|
1300 |
|
1301 if (status != KErrNone) test.Printf(_L("Error: %d\n"), status); |
|
1302 |
|
1303 test.Printf(_L("Test Completed with Error: %d"),status); |
|
1304 |
|
1305 return status; |
|
1306 } |
|
1307 |
|
1308 |
|
1309 // eof |