QuietUnrar/Carthage/Checkouts/UnrarKit/Libraries/unrar/getbits.cpp

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#include "rar.hpp"
BitInput::BitInput(bool AllocBuffer)
{
ExternalBuffer=false;
if (AllocBuffer)
{
// getbits32 attempts to read data from InAddr, ... InAddr+3 positions.
// So let's allocate 3 additional bytes for situation, when we need to
// read only 1 byte from the last position of buffer and avoid a crash
// from access to next 3 bytes, which contents we do not need.
size_t BufSize=MAX_SIZE+3;
InBuf=new byte[BufSize];
// Ensure that we get predictable results when accessing bytes in area
// not filled with read data.
memset(InBuf,0,BufSize);
}
else
InBuf=NULL;
}
BitInput::~BitInput()
{
if (!ExternalBuffer)
delete[] InBuf;
}
void BitInput::faddbits(uint Bits)
{
// Function wrapped version of inline addbits to save code size.
addbits(Bits);
}
uint BitInput::fgetbits()
{
// Function wrapped version of inline getbits to save code size.
return getbits();
}
void BitInput::SetExternalBuffer(byte *Buf)
{
if (InBuf!=NULL && !ExternalBuffer)
delete[] InBuf;
InBuf=Buf;
ExternalBuffer=true;
}