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1 /* |
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2 * Copyright (c) 2002 Nokia Corporation and/or its subsidiary(-ies). |
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3 * All rights reserved. |
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4 * This component and the accompanying materials are made available |
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5 * under the terms of "Eclipse Public License v1.0" |
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6 * which accompanies this distribution, and is available |
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7 * at the URL "http://www.eclipse.org/legal/epl-v10.html". |
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8 * |
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9 * Initial Contributors: |
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10 * Nokia Corporation - initial contribution. |
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11 * |
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12 * Contributors: |
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13 * |
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14 * Description: Bit reader utility |
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15 * |
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16 */ |
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17 |
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18 |
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19 |
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20 // INCLUDE FILES |
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21 #include "nsmldmbitreader.h" |
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22 |
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23 // --------------------------------------------------------- |
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24 // TNSmlDMBitreader::TNSmlDMBitreader() |
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25 // Constructor |
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26 // --------------------------------------------------------- |
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27 TNSmlDMBitreader::TNSmlDMBitreader( const TDesC8& aData ) : RDesReadStream(aData), iByte(0), iBits(0) |
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28 { |
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29 } |
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30 |
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31 // --------------------------------------------------------- |
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32 // TNSmlDMBitreader::ReadUintL() |
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33 // |
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34 // --------------------------------------------------------- |
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35 TUint32 TNSmlDMBitreader::ReadUintL( TInt aBitcount ) |
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36 { |
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37 if( (aBitcount < 0) || (aBitcount > 32) ) |
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38 { |
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39 User::Leave(KErrOverflow); |
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40 } |
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41 |
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42 TUint32 value(0); |
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43 |
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44 while( aBitcount-- ) |
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45 { |
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46 value <<= 1; |
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47 value |= FetchNextBitL(); |
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48 } |
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49 return value; |
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50 } |
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51 |
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52 // --------------------------------------------------------- |
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53 // TNSmlDMBitreader::ReadL() |
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54 // |
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55 // --------------------------------------------------------- |
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56 void TNSmlDMBitreader::ReadL( TInt aBitcount, TDes8& aBuffer ) |
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57 { |
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58 if( (aBitcount>>3) > aBuffer.MaxLength() ) |
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59 { |
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60 User::Leave(KErrOverflow); |
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61 } |
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62 aBuffer.Zero(); |
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63 for( TInt i = 0; i < (aBitcount>>3); i++ ) |
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64 { |
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65 aBuffer.Append((TUint8)ReadUintL(8)); |
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66 } |
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67 } |
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68 // --------------------------------------------------------- |
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69 // TNSmlDMBitreader::FetchNextBitL() |
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70 // |
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71 // --------------------------------------------------------- |
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72 TUint32 TNSmlDMBitreader::FetchNextBitL() |
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73 { |
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74 if( --iBits < 0 ) |
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75 { |
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76 iByte = ReadUint8L(); |
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77 iBits = 7; |
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78 } |
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79 return (iByte>>iBits)&0x1; |
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80 } |
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81 |
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82 |
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83 // End of File |