1 // InBuffer.cpp

     2 

     3 #include "StdAfx.h"

     4 

     5 #include "InBuffer.h"

     6 

     7 extern "C"

     8 {

     9   #include "../../../C/Alloc.h"

    10 }

    11 

    12 CInBuffer::CInBuffer(): 

    13   _buffer(0), 

    14   _bufferLimit(0), 

    15   _bufferBase(0), 

    16   _stream(0),

    17   _bufferSize(0)

    18 {}

    19 

    20 bool CInBuffer::Create(UInt32 bufferSize)

    21 {

    22   const UInt32 kMinBlockSize = 1;

    23   if (bufferSize < kMinBlockSize)

    24     bufferSize = kMinBlockSize;

    25   if (_bufferBase != 0 && _bufferSize == bufferSize)

    26     return true;

    27   Free();

    28   _bufferSize = bufferSize;

    29   _bufferBase = (Byte *)::MidAlloc(bufferSize);

    30   return (_bufferBase != 0);

    31 }

    32 

    33 void CInBuffer::Free()

    34 {

    35   ::MidFree(_bufferBase);

    36   _bufferBase = 0;

    37 }

    38 

    39 void CInBuffer::SetStream(ISequentialInStream *stream)

    40 {

    41   _stream = stream;

    42 }

    43 

    44 void CInBuffer::Init()

    45 {

    46   _processedSize = 0;

    47   _buffer = _bufferBase;

    48   _bufferLimit = _buffer;

    49   _wasFinished = false;

    50   #ifdef _NO_EXCEPTIONS

    51   ErrorCode = S_OK;

    52   #endif

    53 }

    54 

    55 bool CInBuffer::ReadBlock()

    56 {

    57   #ifdef _NO_EXCEPTIONS

    58   if (ErrorCode != S_OK)

    59     return false;

    60   #endif

    61   if (_wasFinished)

    62     return false;

    63   _processedSize += (_buffer - _bufferBase);

    64   UInt32 numProcessedBytes;

    65   HRESULT result = _stream->Read(_bufferBase, _bufferSize, &numProcessedBytes);

    66   #ifdef _NO_EXCEPTIONS

    67   ErrorCode = result;

    68   #else

    69   if (result != S_OK)

    70     throw CInBufferException(result);

    71   #endif

    72   _buffer = _bufferBase;

    73   _bufferLimit = _buffer + numProcessedBytes;

    74   _wasFinished = (numProcessedBytes == 0);

    75   return (!_wasFinished);

    76 }

    77 

    78 Byte CInBuffer::ReadBlock2()

    79 {

    80   if(!ReadBlock())

    81     return 0xFF;

    82   return *_buffer++;

    83 }