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1 // Copyright (c) 1998-2009 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 "US_STD.H" |
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17 |
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18 TInt RFrame16Buf::Offset(TStreamPos aBase,TStreamPos aPos) |
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19 { |
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20 TInt off=aPos-aBase; |
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21 __ASSERT_DEBUG(off>=0,Panic(EStreamPosInvalid)); |
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22 TInt n=off/(KFrameFullLength16+KSizeFrameDes16); |
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23 // number of full frames from base |
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24 off-=n<<KShiftFrameDes16; |
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25 // target offset in frame coordinates |
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26 TInt over=off-(n<<KShiftFrameLength16)-KFrameFullLength16; |
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27 // adjust for overshoot into the frame descriptor |
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28 __ASSERT_DEBUG(over>=-KFrameFullLength16&&over<TInt(KSizeFrameDes16),User::Invariant()); |
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29 if (over>0) |
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30 off-=over; |
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31 return off; |
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32 } |
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33 |
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34 TStreamPos RFrame16Buf::Position(TStreamPos aBase,TInt anOffset) |
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35 { |
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36 return aBase+(anOffset+(anOffset>>KShiftFrameLength16<<KShiftFrameDes16)); |
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37 } |
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38 |
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39 RFrame16Buf::RFrame16Buf(TStreamPos aBase) |
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40 : iBase(aBase),iHost(NULL),iExt(KFrameNonexistent16) |
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41 { |
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42 __ASSERT_DEBUG(aBase>=KStreamBeginning+KSizeFrameDes16,Panic(EStreamPosInvalid)); |
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43 } |
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44 |
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45 TInt RFrame16Buf::ExtendL(TStreamExchange& aHost,TInt anExtent,TInt aMode) |
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46 { |
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47 __ASSERT_DEBUG(anExtent>=0,Panic(EStreamExtentNegative)); |
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48 __ASSERT_DEBUG((KMaskFrameType16&aMode)!=EFrameContinuation16,Panic(EStreamTypeInvalid)); |
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49 TFrameDes16 des[2]={0,TFrameDes16(KMaskFrameType16&aMode|KFrameOpen16)}; |
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50 TUint8* ptr=(TUint8*)&des[1]; |
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51 TInt len=KSizeFrameDes16; |
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52 TStreamPos pos=Position(anExtent); |
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53 TInt off=anExtent; |
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54 anExtent&=KMaskFrameLength16; |
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55 if (anExtent==0) |
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56 pos-=KSizeFrameDes16; |
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57 else |
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58 { |
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59 anExtent=KFrameFullLength16-anExtent; |
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60 if (anExtent>KSizeFrameDes16) |
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61 off+=KSizeFrameDes16; |
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62 else |
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63 { |
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64 ptr-=anExtent; |
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65 len+=anExtent; |
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66 off+=anExtent; |
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67 } |
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68 } |
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69 // |
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70 TStreamMark mark(pos); |
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71 mark.WriteL(aHost,ptr,len); // platform dependency |
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72 mark.Withdraw(aHost); |
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73 Set(aHost,off,0,aMode); |
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74 return off; |
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75 } |
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76 |
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77 void RFrame16Buf::OpenL(TStreamExchange& aHost,TInt anOffset,TInt aMode) |
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78 { |
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79 __ASSERT_DEBUG(anOffset>=0,Panic(EStreamOffsetNegative)); |
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80 __ASSERT_DEBUG((KMaskFrameType16&aMode)!=EFrameContinuation16,Panic(EStreamTypeInvalid)); |
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81 TStreamMark mark(Position(anOffset)-KSizeFrameDes16); |
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82 TFrameDes16 des; |
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83 TInt frame=mark.ReadL(aHost,&des,KSizeFrameDes16); |
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84 // platform dependency |
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85 mark.Withdraw(aHost); |
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86 __ASSERT_DEBUG(frame>=0&&frame<=KSizeFrameDes16,Panic(EStreamReadInBreach)); |
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87 if (frame<KSizeFrameDes16) |
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88 __LEAVE(KErrEof); |
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89 // |
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90 frame=des; |
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91 if ((frame^aMode)&KMaskFrameType16) |
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92 __LEAVE(KErrCorrupt); |
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93 // |
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94 TInt in=anOffset&KMaskFrameLength16; |
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95 frame&=KMaskFrameLength16; |
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96 if (frame==KFrameOpen16) |
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97 frame=KFrameFullLength16-in; |
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98 if (in+frame>KFrameFullLength16) |
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99 __LEAVE(KErrCorrupt); |
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100 // |
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101 Set(aHost,anOffset,anOffset+frame,aMode); |
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102 } |
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103 |
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104 void RFrame16Buf::Set(TStreamExchange& aHost,TInt anOffset,TInt anExtent,TInt aMode) |
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105 { |
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106 __ASSERT_DEBUG(anOffset>=0||anOffset==anExtent,Panic(EStreamOffsetNegative)); |
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107 __ASSERT_DEBUG(anExtent>=0||anOffset==anExtent,Panic(EStreamExtentNegative)); |
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108 iHost=&aHost; |
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109 iOff=anOffset; |
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110 iExt=anExtent; |
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111 TInt lim; |
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112 if (anOffset<0) |
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113 lim=anExtent; |
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114 else |
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115 { |
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116 TStreamPos start=Position(anOffset); |
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117 if (aMode&ERead) |
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118 iRMark=start; |
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119 else |
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120 iRMark.Clear(); |
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121 if (aMode&EWrite) |
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122 iWMark=start; |
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123 else |
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124 iWMark.Clear(); |
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125 lim=(anOffset&~KMaskFrameLength16)+KFrameFullLength16; |
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126 if (anExtent>0&&lim>anExtent) |
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127 lim=anExtent; |
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128 } |
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129 iRAvail=iWAvail=lim-anOffset; |
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130 iRLim=iWLim=lim; |
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131 iMode=aMode; |
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132 } |
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133 |
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134 void RFrame16Buf::CommitL() |
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135 { |
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136 __ASSERT_DEBUG(!IsCommitted(),Panic(EStreamCommitted)); |
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137 TInt ext=Host().SizeL()-Base().Offset(); |
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138 if (ext<0) |
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139 __LEAVE(KErrCorrupt); |
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140 // |
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141 TInt n=ext/(KFrameFullLength16+KSizeFrameDes16); |
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142 // number of full frames from base |
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143 ext-=n<<KShiftFrameDes16; |
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144 // end in frame coordinates |
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145 TInt off=Offset(); |
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146 if (ext==off) |
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147 { // committing an empty stream |
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148 iOff=iExt=KFrameNonexistent16; |
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149 return; |
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150 } |
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151 // |
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152 TInt frame=ext-(n<<KShiftFrameLength16); |
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153 // size of final frame (remainder of the division above) |
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154 __ASSERT_DEBUG(frame>=0&&frame<KFrameFullLength16+KSizeFrameDes16,User::Invariant()); |
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155 if (ext<off||frame==0||frame>KFrameFullLength16) |
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156 __LEAVE(KErrCorrupt); // bad offset, empty frame or partial frame descriptor |
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157 // |
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158 if (frame<KFrameFullLength16) |
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159 { |
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160 TFrameDes16 des; |
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161 if ((off^ext)&~KMaskFrameLength16) |
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162 { // in a different frame from the one we started in |
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163 off=ext&~KMaskFrameLength16; |
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164 des=TFrameDes16(EFrameContinuation16|frame); |
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165 } |
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166 else |
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167 { |
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168 frame-=off&KMaskFrameLength16; |
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169 __ASSERT_DEBUG(frame>0&&frame<KFrameFullLength16,User::Invariant()); |
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170 des=TFrameDes16(iMode&KMaskFrameType16|frame); |
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171 } |
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172 TStreamMark mark(Position(off)-KSizeFrameDes16); |
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173 mark.WriteL(Host(),&des,KSizeFrameDes16); |
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174 mark.Withdraw(Host()); |
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175 } |
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176 iExt=ext; |
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177 } |
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178 |
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179 void RFrame16Buf::DoRelease() |
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180 { |
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181 if (iHost!=NULL) |
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182 { |
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183 iRMark.Withdraw(*iHost); |
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184 iWMark.Withdraw(*iHost); |
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185 iHost=NULL; |
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186 iExt=KFrameNonexistent16; |
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187 } |
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188 } |
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189 |
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190 void RFrame16Buf::DoSynchL() |
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191 { |
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192 if (IsCommitted()) |
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193 return; |
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194 // |
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195 CommitL(); |
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196 } |
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197 |
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198 TInt RFrame16Buf::DoReadL(TAny* aPtr,TInt aMaxLength) |
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199 { |
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200 __ASSERT_DEBUG(aMaxLength>=0,Panic(EStreamReadLengthNegative)); |
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201 __ASSERT_DEBUG(aMaxLength>0,Panic(EStreamReadNoTransfer)); |
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202 TInt left=aMaxLength; |
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203 TInt avail=iRAvail; |
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204 if (avail==0) |
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205 goto underflow; // we'd used up the whole frame |
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206 // |
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207 do |
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208 { |
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209 __ASSERT_DEBUG(left>0&&avail>0,User::Invariant()); |
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210 { |
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211 TInt len=iRMark.ReadL(Host(),aPtr,Min(left,avail)); |
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212 __ASSERT_DEBUG(len>=0&&len<=left&&len<=avail,Panic(EStreamReadInBreach)); |
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213 iRAvail=avail-=len; |
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214 left-=len; |
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215 if (left==0) |
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216 return aMaxLength; // that's it |
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217 // |
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218 aPtr=(TUint8*)aPtr+len; |
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219 } |
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220 if (avail>0) |
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221 { // we've run out of host |
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222 if ((Extent()&KMaskFrameLength16)==KFrameOpen16) |
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223 break; // all's well, provided we're open-ended |
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224 // |
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225 iRMark.Withdraw(Host()); |
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226 __LEAVE(KErrCorrupt); |
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227 } |
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228 // |
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229 underflow: |
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230 avail=UnderflowL(); |
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231 } while (avail>0); |
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232 return aMaxLength-left; |
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233 } |
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234 |
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235 TInt RFrame16Buf::DoReadL(TDes8& aDes,TInt aMaxLength,TRequestStatus& aStatus) |
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236 // |
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237 // Read up to aMaxLength bytes asynchronously. |
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238 // |
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239 { |
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240 //#pragma message( __FILE__ " : 'RFrame16Buf::DoReadL(TDes8&,TInt,TRequestStatus&)' not implemented" ) |
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241 __ASSERT_DEBUG(aMaxLength<=aDes.MaxLength(),Panic(EStreamReadBeyondEnd)); |
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242 aDes.SetLength(DoReadL((TUint8*)aDes.Ptr(),aMaxLength)); |
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243 TRequestStatus* stat=&aStatus; |
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244 User::RequestComplete(stat,KErrNone); |
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245 return aMaxLength; |
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246 } |
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247 |
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248 TStreamTransfer RFrame16Buf::DoReadL(MStreamInput& anInput,TStreamTransfer aTransfer) |
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249 { |
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250 __ASSERT_DEBUG(aTransfer>0,Panic(EStreamReadNoTransfer)); |
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251 if (iRAvail>0) |
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252 { |
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253 TInt len=iRMark.ReadL(Host(),anInput,aTransfer[iRAvail]); |
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254 aTransfer-=len; |
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255 iRAvail-=len; |
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256 } |
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257 if (aTransfer>0) |
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258 return anInput.ReadFromL(*this,aTransfer); |
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259 // |
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260 return aTransfer; |
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261 } |
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262 |
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263 void RFrame16Buf::DoWriteL(const TAny* aPtr,TInt aLength) |
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264 { |
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265 __ASSERT_DEBUG(aLength>=0,Panic(EStreamWriteLengthNegative)); |
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266 __ASSERT_DEBUG(aLength>0,Panic(EStreamWriteNoTransfer)); |
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267 TInt avail=iWAvail; |
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268 if (avail==0) |
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269 goto overflow; // we'd used up the whole frame |
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270 // |
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271 for (;;) |
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272 { |
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273 __ASSERT_DEBUG(aLength>0&&avail>0,User::Invariant()); |
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274 { |
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275 TInt len=Min(aLength,avail); |
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276 iWMark.WriteL(Host(),aPtr,len); |
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277 iWAvail=avail-len; |
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278 aLength-=len; |
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279 if (aLength==0) |
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280 return; // won't worry about the next frame just yet |
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281 // |
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282 aPtr=(TUint8*)aPtr+len; |
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283 } |
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284 overflow: |
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285 OverflowL(); |
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286 avail=iWAvail; |
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287 }; |
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288 } |
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289 |
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290 TInt RFrame16Buf::DoWriteL(const TDesC8& aDes,TInt aMaxLength,TRequestStatus& aStatus) |
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291 // |
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292 // Write up to aMaxLength bytes asynchronously. |
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293 // |
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294 { |
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295 //#pragma message( __FILE__ " : 'RFrame16Buf::DoWriteL(const TDesC8&,TInt,TRequestStatus&)' not implemented" ) |
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296 __ASSERT_DEBUG(aMaxLength<=aDes.Length(),Panic(EStreamWriteBeyondEnd)); |
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297 DoWriteL(aDes.Ptr(),aMaxLength); |
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298 TRequestStatus* stat=&aStatus; |
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299 User::RequestComplete(stat,KErrNone); |
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300 return aMaxLength; |
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301 } |
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302 |
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303 TStreamTransfer RFrame16Buf::DoWriteL(MStreamOutput& anOutput,TStreamTransfer aTransfer) |
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304 { |
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305 __ASSERT_DEBUG(aTransfer>0,Panic(EStreamWriteNoTransfer)); |
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306 if (iWAvail>0) |
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307 { |
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308 TInt len=iWMark.WriteL(Host(),anOutput,aTransfer[iWAvail]); |
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309 aTransfer-=len; |
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310 iWAvail-=len; |
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311 } |
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312 if (aTransfer>0) |
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313 return anOutput.WriteToL(*this,aTransfer); |
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314 // |
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315 return aTransfer; |
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316 } |
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317 |
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318 TStreamPos RFrame16Buf::DoSeekL(TMark aMark,TStreamLocation aLocation,TInt anOffset) |
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319 // |
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320 // Position the mark(s) indicated by aMark at anOffset from aLocation. |
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321 // |
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322 { |
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323 switch (aLocation) |
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324 { |
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325 case EStreamBeginning: |
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326 anOffset+=Offset(); |
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327 break; |
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328 case EStreamMark: |
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329 if (aMark==ERead) |
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330 anOffset+=iRLim-iRAvail; |
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331 else |
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332 { |
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333 __ASSERT_ALWAYS(aMark==EWrite,Panic(EStreamMarkInvalid)); |
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334 anOffset+=iWLim-iWAvail; |
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335 } |
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336 break; |
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337 case EStreamEnd: |
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338 anOffset+=EndL(); |
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339 break; |
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340 default: |
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341 Panic(EStreamLocationInvalid); |
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342 break; |
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343 } |
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344 TInt r=KErrNone; |
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345 if (anOffset<Offset()) |
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346 { |
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347 anOffset=Offset(); |
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348 r=KErrEof; |
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349 } |
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350 else if (anOffset>=0&&!ReachL(anOffset)) |
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351 { |
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352 __ASSERT_DEBUG(Extent()!=0,User::Invariant()); |
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353 anOffset=Extent(); |
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354 r=KErrEof; |
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355 } |
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356 // |
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357 if (aMark&&anOffset>=0) |
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358 { |
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359 __ASSERT_ALWAYS(!(aMark&~(ERead|EWrite)),Panic(EStreamMarkInvalid)); |
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360 TInt in=anOffset&KMaskFrameLength16; |
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361 TInt off=anOffset-in; |
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362 __ASSERT_DEBUG(Extent()==0||anOffset<=Extent(),User::Invariant()); |
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363 if (in==0&&off>Offset()&&(Extent()==0||off==Extent())) |
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364 { // positioning at the start of a frame that may not exist |
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365 in=KFrameFullLength16; |
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366 off-=in; |
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367 } |
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368 TStreamPos pos=Base()+(off+(off>>KShiftFrameLength16<<KShiftFrameDes16))+in; |
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369 TInt lim=off+KFrameFullLength16; |
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370 if (Extent()>0&&lim>Extent()) |
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371 lim=Extent(); |
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372 TInt left=lim-anOffset; |
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373 __ASSERT_DEBUG(left>=0&&left<=KFrameFullLength16,User::Invariant()); |
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374 // |
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375 if (aMark&ERead) |
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376 { |
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377 if (iMode&ERead) |
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378 iRMark.SeekL(Host(),pos); |
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379 iRAvail=left; |
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380 iRLim=lim; |
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381 } |
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382 if (aMark&EWrite) |
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383 { |
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384 if (iMode&EWrite) |
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385 iWMark.SeekL(Host(),pos); |
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386 iWAvail=left; |
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387 iWLim=lim; |
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388 } |
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389 } |
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390 __LEAVE_IF_ERROR(r); |
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391 return TStreamPos(anOffset-Offset()); |
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392 } |
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393 |
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394 TInt RFrame16Buf::UnderflowL() |
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395 { |
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396 __ASSERT_DEBUG(iRAvail==0,User::Invariant()); |
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397 if ((iRLim&KMaskFrameLength16)!=KFrameOpen16) |
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398 { |
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399 __ASSERT_DEBUG(iExt==iRLim,User::Invariant()); |
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400 return 0; // we've used up the closing, partial frame |
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401 } |
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402 // |
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403 __ASSERT_DEBUG(iRLim>0&&(iExt>0&&iRLim<=iExt||iExt==0),User::Invariant()); |
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404 // let's see if there's a continuation frame |
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405 TFrameDes16 des; |
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406 TInt frame=iRMark.ReadL(Host(),&des,KSizeFrameDes16); |
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407 // platform dependency |
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408 __ASSERT_DEBUG(frame>=0&&frame<=KSizeFrameDes16,Panic(EStreamReadInBreach)); |
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409 if (frame==KSizeFrameDes16) |
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410 { |
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411 frame=des; |
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412 if ((frame&KMaskFrameType16)==EFrameContinuation16) |
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413 { // we have a continuation frame, prepare ourselves for it |
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414 frame&=KMaskFrameLength16; |
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415 if (frame==KFrameOpen16) |
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416 frame=KFrameFullLength16; |
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417 iRAvail=frame; |
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418 TInt lim=iRLim; |
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419 iRLim=lim+frame; |
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420 if (iExt==lim) |
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421 iExt=iRLim; |
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422 return frame; |
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423 } |
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424 iRMark.SeekL(Host(),-KSizeFrameDes16); |
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425 frame=0; |
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426 } |
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427 // |
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428 if (frame>0||iRLim<iExt) |
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429 { // we'd definitely seen a continuation frame here before |
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430 iRMark.Withdraw(Host()); |
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431 __LEAVE(KErrCorrupt); |
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432 } |
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433 return 0; |
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434 } |
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435 |
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436 void RFrame16Buf::OverflowL() |
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437 { |
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438 __ASSERT_DEBUG(iWAvail==0,User::Invariant()); |
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439 if ((iWLim&KMaskFrameLength16)!=KFrameOpen16) |
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440 { // filled the closing, partial frame |
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441 __ASSERT_DEBUG(iExt==iWLim,User::Invariant()); |
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442 overflow: |
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443 iWMark.Withdraw(Host()); |
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444 __LEAVE(KErrOverflow); |
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445 } |
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446 // |
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447 __ASSERT_DEBUG(iWLim>0&&(iExt>0&&iWLim<=iExt||iExt==0),User::Invariant()); |
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448 if (iWLim==iExt) |
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449 { // let's see if this carries on |
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450 TFrameDes16 des; |
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451 TInt frame=iWMark.ReadL(Host(),&des,KSizeFrameDes16); |
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452 // platform dependency |
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453 __ASSERT_DEBUG(frame>=0&&frame<=KSizeFrameDes16,Panic(EStreamReadInBreach)); |
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454 if (frame==0) |
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455 iExt=0; // end-of-host, let's start extending |
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456 else |
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457 { |
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458 if (frame==KSizeFrameDes16) |
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459 { |
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460 frame=des; |
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461 if ((frame&KMaskFrameType16)==EFrameContinuation16) |
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462 { // there's more, set up for the next frame |
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463 frame&=KMaskFrameLength16; |
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464 if (frame==KFrameOpen16) |
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465 frame=KFrameFullLength16; |
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466 iWAvail=frame; |
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467 iExt=iWLim+=frame; |
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468 return; |
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469 } |
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470 goto overflow; |
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471 } |
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472 // |
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473 iWMark.Withdraw(Host()); |
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474 __LEAVE(KErrCorrupt); |
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475 } |
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476 } |
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477 // |
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478 __ASSERT_DEBUG(iWLim<iExt||iExt==0,User::Invariant()); |
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479 // calculate the frame descriptor to be written |
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480 TInt frame=iExt&KMaskFrameLength16; |
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481 if (iWLim<iExt-frame) |
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482 frame=KFrameOpen16; |
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483 TFrameDes16 des=TFrameDes16(EFrameContinuation16|frame); |
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484 if (frame==KFrameOpen16) |
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485 frame=KFrameFullLength16; |
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486 iWMark.WriteL(Host(),&des,KSizeFrameDes16); |
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487 // platform dependency |
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488 iWAvail=frame; |
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489 iWLim+=frame; |
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490 } |
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491 |
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492 TBool RFrame16Buf::ReachL(TInt anOffset) |
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493 { |
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494 if (iExt<=0) |
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495 return iExt==0; |
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496 // |
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497 TStreamMark mark(Base()); |
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498 TInt frame=(iExt+(iExt>>KShiftFrameLength16<<KShiftFrameDes16))-KSizeFrameDes16; |
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499 while (iExt<anOffset) |
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500 { |
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501 if ((iExt&KMaskFrameLength16)!=KFrameOpen16) |
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502 { |
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503 mark.Withdraw(Host()); |
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504 return EFalse; |
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505 } |
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506 // |
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507 TFrameDes16 des; |
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508 mark.SeekL(Host(),EStreamMark,frame); |
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509 frame=mark.ReadL(Host(),&des,KSizeFrameDes16); |
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510 // platform dependency |
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511 __ASSERT_DEBUG(frame>=0&&frame<=KSizeFrameDes16,Panic(EStreamReadInBreach)); |
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512 if (frame==KSizeFrameDes16) |
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513 { |
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514 frame=des; |
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515 if ((frame&KMaskFrameType16)==EFrameContinuation16) |
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516 { // we have a continuation frame, boost upper |
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517 frame&=KMaskFrameLength16; |
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518 if (frame==KFrameOpen16) |
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519 frame=KFrameFullLength16; |
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520 iExt+=frame; |
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521 continue; |
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522 } |
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523 frame=0; |
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524 } |
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525 // |
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526 mark.Withdraw(Host()); |
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527 if (frame>0) |
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528 __LEAVE(KErrCorrupt); |
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529 // |
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530 return EFalse; |
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531 } |
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532 mark.Withdraw(Host()); |
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533 return ETrue; |
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534 } |
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535 |
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536 TInt RFrame16Buf::EndL() |
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537 { |
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538 TInt ext=Host().SizeL()-Base().Offset(); |
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539 if (ext<0) |
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540 __LEAVE(KErrCorrupt); |
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541 // |
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542 TInt n=ext/(KFrameFullLength16+KSizeFrameDes16); |
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543 // number of full frames from base |
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544 ext-=n<<KShiftFrameDes16; |
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545 // end in frame coordinates |
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546 TInt frame=ext-(n<<KShiftFrameLength16); |
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547 // size of final frame (remainder of the division above) |
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548 __ASSERT_DEBUG(frame>=0&&frame<KFrameFullLength16+KSizeFrameDes16,User::Invariant()); |
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549 if (ext<Offset()||frame>KFrameFullLength16) |
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550 __LEAVE(KErrCorrupt); // bad offset or partial frame descriptor |
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551 // |
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552 if (!ReachL(ext)) |
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553 { |
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554 __ASSERT_DEBUG(Extent()!=0,User::Invariant()); |
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555 return Extent(); |
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556 } |
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557 // |
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558 return ext; |
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559 } |
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560 |