BitStream.cpp

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#if defined(_MSC_VER) && _MSC_VER < 1299 // VC6 doesn't support template specialization
#include "BitStream_NoTemplate.cpp"
#else

#include "BitStream.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#include "SocketIncludes.h"

#if defined(_XBOX) || defined(X360)
                            
#elif defined(_WIN32)
#include <winsock2.h> // htonl
#include <memory.h>
#include <cmath>
#include <float.h>
#elif defined(_PS3) || defined(__PS3__) || defined(SN_TARGET_PS3)
                        
#else
#include <arpa/inet.h>
#include <memory.h>
#include <cmath>
#include <float.h>
#endif

// MSWin uses _copysign, others use copysign...
#ifndef _WIN32
#define _copysign copysign
#endif



using namespace RakNet;

#ifdef _MSC_VER
#pragma warning( push )
#endif

BitStream::BitStream()
{
        numberOfBitsUsed = 0;
        //numberOfBitsAllocated = 32 * 8;
        numberOfBitsAllocated = BITSTREAM_STACK_ALLOCATION_SIZE * 8;
        readOffset = 0;
        //data = ( unsigned char* ) rakMalloc_Ex( 32, __FILE__, __LINE__ );
        data = ( unsigned char* ) stackData;

#ifdef _DEBUG   
        //      RakAssert( data );
#endif
        //memset(data, 0, 32);
        copyData = true;
}

BitStream::BitStream( const unsigned int initialBytesToAllocate )
{
        numberOfBitsUsed = 0;
        readOffset = 0;
        if (initialBytesToAllocate <= BITSTREAM_STACK_ALLOCATION_SIZE)
        {
                data = ( unsigned char* ) stackData;
                numberOfBitsAllocated = BITSTREAM_STACK_ALLOCATION_SIZE * 8;
        }
        else
        {
                data = ( unsigned char* ) rakMalloc_Ex( (size_t) initialBytesToAllocate, __FILE__, __LINE__ );
                numberOfBitsAllocated = initialBytesToAllocate << 3;
        }
#ifdef _DEBUG
        RakAssert( data );
#endif
        // memset(data, 0, initialBytesToAllocate);
        copyData = true;
}

BitStream::BitStream( unsigned char* _data, const unsigned int lengthInBytes, bool _copyData )
{
        numberOfBitsUsed = lengthInBytes << 3;
        readOffset = 0;
        copyData = _copyData;
        numberOfBitsAllocated = lengthInBytes << 3;

        if ( copyData )
        {
                if ( lengthInBytes > 0 )
                {
                        if (lengthInBytes < BITSTREAM_STACK_ALLOCATION_SIZE)
                        {
                                data = ( unsigned char* ) stackData;
                                numberOfBitsAllocated = BITSTREAM_STACK_ALLOCATION_SIZE << 3;
                        }
                        else
                        {
                                data = ( unsigned char* ) rakMalloc_Ex( (size_t) lengthInBytes, __FILE__, __LINE__ );
                        }
#ifdef _DEBUG
                        RakAssert( data );
#endif
                        memcpy( data, _data, (size_t) lengthInBytes );
                }
                else
                        data = 0;
        }
        else
                data = ( unsigned char* ) _data;
}

// Use this if you pass a pointer copy to the constructor (_copyData==false) and want to overallocate to prevent reallocation
void BitStream::SetNumberOfBitsAllocated( const BitSize_t lengthInBits )
{
#ifdef _DEBUG
        RakAssert( lengthInBits >= ( BitSize_t ) numberOfBitsAllocated );
#endif  
        numberOfBitsAllocated = lengthInBits;
}

BitStream::~BitStream()
{
        if ( copyData && numberOfBitsAllocated > (BITSTREAM_STACK_ALLOCATION_SIZE << 3))
                rakFree_Ex( data , __FILE__, __LINE__ );  // Use realloc and free so we are more efficient than delete and new for resizing
}

void BitStream::Reset( void )
{
        // Note:  Do NOT reallocate memory because BitStream is used
        // in places to serialize/deserialize a buffer. Reallocation
        // is a dangerous operation (may result in leaks).

        if ( numberOfBitsUsed > 0 )
        {
                //  memset(data, 0, BITS_TO_BYTES(numberOfBitsUsed));
        }

        // Don't free memory here for speed efficiency
        //free(data);  // Use realloc and free so we are more efficient than delete and new for resizing
        numberOfBitsUsed = 0;

        //numberOfBitsAllocated=8;
        readOffset = 0;

        //data=(unsigned char*)rakMalloc_Ex(1, __FILE__, __LINE__);
        // if (numberOfBitsAllocated>0)
        //  memset(data, 0, BITS_TO_BYTES(numberOfBitsAllocated));
}

// Write an array or casted stream
void BitStream::Write( const char* inputByteArray, const unsigned int numberOfBytes )
{
        if (numberOfBytes==0)
                return;

        // Optimization:
        if ((numberOfBitsUsed & 7) == 0)
        {
                AddBitsAndReallocate( BYTES_TO_BITS(numberOfBytes) );
                memcpy(data+BITS_TO_BYTES(numberOfBitsUsed), inputByteArray, (size_t) numberOfBytes);
                numberOfBitsUsed+=BYTES_TO_BITS(numberOfBytes);
        }
        else
        {
                WriteBits( ( unsigned char* ) inputByteArray, numberOfBytes * 8, true );
        }

}
void BitStream::Write( BitStream *bitStream)
{
        Write(bitStream, bitStream->GetNumberOfBitsUsed());
}
void BitStream::Write( BitStream *bitStream, BitSize_t numberOfBits )
{
        AddBitsAndReallocate( numberOfBits );
        BitSize_t numberOfBitsMod8;

        if ((bitStream->GetReadOffset()&7)==0 && (numberOfBitsUsed&7)==0)
        {
                int readOffsetBytes=bitStream->GetReadOffset()/8;
                int numBytes=numberOfBits/8;
                memcpy(data + (numberOfBitsUsed >> 3), bitStream->GetData()+readOffsetBytes, numBytes);
                numberOfBits-=BYTES_TO_BITS(numBytes);
                bitStream->SetReadOffset(BYTES_TO_BITS(numBytes+readOffsetBytes));
                numberOfBitsUsed+=BYTES_TO_BITS(numBytes);
        }

        while (numberOfBits-->0 && bitStream->readOffset + 1 <= bitStream->numberOfBitsUsed)
        {
                numberOfBitsMod8 = numberOfBitsUsed & 7;
                if ( numberOfBitsMod8 == 0 )
                {
                        // New byte
                        if (bitStream->data[ bitStream->readOffset >> 3 ] & ( 0x80 >> ( bitStream->readOffset & 7 ) ) )
                        {
                                // Write 1
                                data[ numberOfBitsUsed >> 3 ] = 0x80;
                        }
                        else
                        {
                                // Write 0
                                data[ numberOfBitsUsed >> 3 ] = 0;
                        }

                }
                else
                {
                        // Existing byte
                        if (bitStream->data[ bitStream->readOffset >> 3 ] & ( 0x80 >> ( bitStream->readOffset & 7 ) ) )
                                data[ numberOfBitsUsed >> 3 ] |= 0x80 >> ( numberOfBitsMod8 ); // Set the bit to 1
                        // else 0, do nothing
                }

                bitStream->readOffset++;
                numberOfBitsUsed++;
        }
}
void BitStream::Write( BitStream &bitStream, BitSize_t numberOfBits )
{
        Write(&bitStream, numberOfBits);
}
void BitStream::Write( BitStream &bitStream )
{
        Write(&bitStream);
}
bool BitStream::Read( BitStream *bitStream, BitSize_t numberOfBits )
{
        if (GetNumberOfUnreadBits() < numberOfBits)
                return false;
        bitStream->Write(this, numberOfBits);
        return true;
}
bool BitStream::Read( BitStream *bitStream )
{
        bitStream->Write(this);
        return true;
}
bool BitStream::Read( BitStream &bitStream, BitSize_t numberOfBits )
{
        if (GetNumberOfUnreadBits() < numberOfBits)
                return false;
        bitStream.Write(this, numberOfBits);
        return true;
}
bool BitStream::Read( BitStream &bitStream )
{
        bitStream.Write(this);
        return true;
}

// Read an array or casted stream
bool BitStream::Read( char* outByteArray, const unsigned int numberOfBytes )
{
        // Optimization:
        if ((readOffset & 7) == 0)
        {
                if ( readOffset + ( numberOfBytes << 3 ) > numberOfBitsUsed )
                        return false;

                // Write the data
                memcpy( outByteArray, data + ( readOffset >> 3 ), (size_t) numberOfBytes );

                readOffset += numberOfBytes << 3;
                return true;
        }
        else
        {
                return ReadBits( ( unsigned char* ) outByteArray, numberOfBytes * 8 );
        }
}

// Sets the read pointer back to the beginning of your data.
void BitStream::ResetReadPointer( void )
{
        readOffset = 0;
}

// Sets the write pointer back to the beginning of your data.
void BitStream::ResetWritePointer( void )
{
        numberOfBitsUsed = 0;
}

// Write a 0
void BitStream::Write0( void )
{
        AddBitsAndReallocate( 1 );

        // New bytes need to be zeroed
        if ( ( numberOfBitsUsed & 7 ) == 0 )
                data[ numberOfBitsUsed >> 3 ] = 0;

        numberOfBitsUsed++;
}

// Write a 1
void BitStream::Write1( void )
{
        AddBitsAndReallocate( 1 );

        BitSize_t numberOfBitsMod8 = numberOfBitsUsed & 7;

        if ( numberOfBitsMod8 == 0 )
                data[ numberOfBitsUsed >> 3 ] = 0x80;
        else
                data[ numberOfBitsUsed >> 3 ] |= 0x80 >> ( numberOfBitsMod8 ); // Set the bit to 1

        numberOfBitsUsed++;
}

// Returns true if the next data read is a 1, false if it is a 0
bool BitStream::ReadBit( void )
{
        bool result = ( data[ readOffset >> 3 ] & ( 0x80 >> ( readOffset & 7 ) ) ) !=0;
        readOffset++;
        return result;
}

// Align the bitstream to the byte boundary and then write the specified number of bits.
// This is faster than WriteBits but wastes the bits to do the alignment and requires you to call
// SetReadToByteAlignment at the corresponding read position
void BitStream::WriteAlignedBytes( const unsigned char* inByteArray, const unsigned int numberOfBytesToWrite )
{
        AlignWriteToByteBoundary();
        Write((const char*) inByteArray, numberOfBytesToWrite);
}
void BitStream::EndianSwapBytes( int byteOffset, int length )
{
        if (DoEndianSwap())
        {
                ReverseBytesInPlace(data+byteOffset, length);
        }
}
void BitStream::WriteAlignedBytesSafe( const char *inByteArray, const unsigned int inputLength, const unsigned int maxBytesToWrite )
{
        if (inByteArray==0 || inputLength==0)
        {
                WriteCompressed((unsigned int)0);
                return;
        }
        WriteCompressed(inputLength);
        WriteAlignedBytes((const unsigned char*) inByteArray, inputLength < maxBytesToWrite ? inputLength : maxBytesToWrite);
}

// Read bits, starting at the next aligned bits. Note that the modulus 8 starting offset of the
// sequence must be the same as was used with WriteBits. This will be a problem with packet coalescence
// unless you byte align the coalesced packets.
bool BitStream::ReadAlignedBytes( unsigned char* inOutByteArray, const unsigned int numberOfBytesToRead )
{
#ifdef _DEBUG
        RakAssert( numberOfBytesToRead > 0 );
#endif

        if ( numberOfBytesToRead <= 0 )
                return false;

        // Byte align
        AlignReadToByteBoundary();

        if ( readOffset + ( numberOfBytesToRead << 3 ) > numberOfBitsUsed )
                return false;

        // Write the data
        memcpy( inOutByteArray, data + ( readOffset >> 3 ), (size_t) numberOfBytesToRead );

        readOffset += numberOfBytesToRead << 3;

        return true;
}
bool BitStream::ReadAlignedBytesSafe( char *inOutByteArray, int &inputLength, const int maxBytesToRead )
{
        return ReadAlignedBytesSafe(inOutByteArray,(unsigned int&) inputLength,(unsigned int)maxBytesToRead);
}
bool BitStream::ReadAlignedBytesSafe( char *inOutByteArray, unsigned int &inputLength, const unsigned int maxBytesToRead )
{
        if (ReadCompressed(inputLength)==false)
                return false;
        if (inputLength > maxBytesToRead)
                inputLength=maxBytesToRead;
        if (inputLength==0)
                return true;
        return ReadAlignedBytes((unsigned char*) inOutByteArray, inputLength);
}
bool BitStream::ReadAlignedBytesSafeAlloc( char **outByteArray, int &inputLength, const unsigned int maxBytesToRead )
{
        return ReadAlignedBytesSafeAlloc(outByteArray,(unsigned int&) inputLength, maxBytesToRead);
}
bool BitStream::ReadAlignedBytesSafeAlloc( char ** outByteArray, unsigned int &inputLength, const unsigned int maxBytesToRead )
{
        rakFree_Ex(*outByteArray, __FILE__, __LINE__ );
        *outByteArray=0;
        if (ReadCompressed(inputLength)==false)
                return false;
        if (inputLength > maxBytesToRead)
                inputLength=maxBytesToRead;
        if (inputLength==0)
                return true;
        *outByteArray = (char*) rakMalloc_Ex( (size_t) inputLength, __FILE__, __LINE__ );
        return ReadAlignedBytes((unsigned char*) *outByteArray, inputLength);
}

// Write numberToWrite bits from the input source
void BitStream::WriteBits( const unsigned char* inByteArray, BitSize_t numberOfBitsToWrite, const bool rightAlignedBits )
{
//      if (numberOfBitsToWrite<=0)
//              return;

        AddBitsAndReallocate( numberOfBitsToWrite );

        const BitSize_t numberOfBitsUsedMod8 = numberOfBitsUsed & 7;

        // If currently aligned and numberOfBits is a multiple of 8, just memcpy for speed
        if (numberOfBitsUsedMod8==0 && (numberOfBitsToWrite&7)==0)
        {
                memcpy( data + ( numberOfBitsUsed >> 3 ), inByteArray, numberOfBitsToWrite>>3);
                numberOfBitsUsed+=numberOfBitsToWrite;
                return;
        }

        unsigned char dataByte;
        const unsigned char* inputPtr=inByteArray;

        // Faster to put the while at the top surprisingly enough
        while ( numberOfBitsToWrite > 0 )
                //do
        {
                dataByte = *( inputPtr++ );

                if ( numberOfBitsToWrite < 8 && rightAlignedBits )   // rightAlignedBits means in the case of a partial byte, the bits are aligned from the right (bit 0) rather than the left (as in the normal internal representation)
                        dataByte <<= 8 - numberOfBitsToWrite;  // shift left to get the bits on the left, as in our internal representation

                // Writing to a new byte each time
                if ( numberOfBitsUsedMod8 == 0 )
                        * ( data + ( numberOfBitsUsed >> 3 ) ) = dataByte;
                else
                {
                        // Copy over the new data.
                        *( data + ( numberOfBitsUsed >> 3 ) ) |= dataByte >> ( numberOfBitsUsedMod8 ); // First half

                        if ( 8 - ( numberOfBitsUsedMod8 ) < 8 && 8 - ( numberOfBitsUsedMod8 ) < numberOfBitsToWrite )   // If we didn't write it all out in the first half (8 - (numberOfBitsUsed%8) is the number we wrote in the first half)
                        {
                                *( data + ( numberOfBitsUsed >> 3 ) + 1 ) = (unsigned char) ( dataByte << ( 8 - ( numberOfBitsUsedMod8 ) ) ); // Second half (overlaps byte boundary)
                        }
                }

                if ( numberOfBitsToWrite >= 8 )
                {
                        numberOfBitsUsed += 8;
                        numberOfBitsToWrite -= 8;
                }
                else
                {
                        numberOfBitsUsed += numberOfBitsToWrite;
                        numberOfBitsToWrite=0;
                }
        }
        // } while(numberOfBitsToWrite>0);
}

// Set the stream to some initial data.  For internal use
void BitStream::SetData( unsigned char *inByteArray )
{
        data=inByteArray;
        copyData=false;
}

// Assume the input source points to a native type, compress and write it
void BitStream::WriteCompressed( const unsigned char* inByteArray,
                                                                const unsigned int size, const bool unsignedData )
{
        BitSize_t currentByte = ( size >> 3 ) - 1; // PCs

        unsigned char byteMatch;

        if ( unsignedData )
        {
                byteMatch = 0;
        }

        else
        {
                byteMatch = 0xFF;
        }

        // Write upper bytes with a single 1
        // From high byte to low byte, if high byte is a byteMatch then write a 1 bit. Otherwise write a 0 bit and then write the remaining bytes
        while ( currentByte > 0 )
        {
                if ( inByteArray[ currentByte ] == byteMatch )   // If high byte is byteMatch (0 of 0xff) then it would have the same value shifted
                {
                        bool b = true;
                        Write( b );
                }
                else
                {
                        // Write the remainder of the data after writing 0
                        bool b = false;
                        Write( b );

                        WriteBits( inByteArray, ( currentByte + 1 ) << 3, true );
                        //  currentByte--;


                        return ;
                }

                currentByte--;
        }

        // If the upper half of the last byte is a 0 (positive) or 16 (negative) then write a 1 and the remaining 4 bits.  Otherwise write a 0 and the 8 bites.
        if ( ( unsignedData && ( ( *( inByteArray + currentByte ) ) & 0xF0 ) == 0x00 ) ||
                ( unsignedData == false && ( ( *( inByteArray + currentByte ) ) & 0xF0 ) == 0xF0 ) )
        {
                bool b = true;
                Write( b );
                WriteBits( inByteArray + currentByte, 4, true );
        }

        else
        {
                bool b = false;
                Write( b );
                WriteBits( inByteArray + currentByte, 8, true );
        }
}

// Read numberOfBitsToRead bits to the output source
// alignBitsToRight should be set to true to convert internal bitstream data to userdata
// It should be false if you used WriteBits with rightAlignedBits false
bool BitStream::ReadBits( unsigned char *inOutByteArray, BitSize_t numberOfBitsToRead, const bool alignBitsToRight )
{
#ifdef _DEBUG
        //      RakAssert( numberOfBitsToRead > 0 );
#endif
        if (numberOfBitsToRead<=0)
                return false;

        if ( readOffset + numberOfBitsToRead > numberOfBitsUsed )
                return false;


        const BitSize_t readOffsetMod8 = readOffset & 7;

        // If currently aligned and numberOfBits is a multiple of 8, just memcpy for speed
        if (readOffsetMod8==0 && (numberOfBitsToRead&7)==0)
        {
                memcpy( inOutByteArray, data + ( readOffset >> 3 ), numberOfBitsToRead>>3);
                readOffset+=numberOfBitsToRead;
                return true;
        }



        BitSize_t offset = 0;

        memset( inOutByteArray, 0, (size_t) BITS_TO_BYTES( numberOfBitsToRead ) );

        while ( numberOfBitsToRead > 0 )
        {
                *( inOutByteArray + offset ) |= *( data + ( readOffset >> 3 ) ) << ( readOffsetMod8 ); // First half

                if ( readOffsetMod8 > 0 && numberOfBitsToRead > 8 - ( readOffsetMod8 ) )   // If we have a second half, we didn't read enough bytes in the first half
                        *( inOutByteArray + offset ) |= *( data + ( readOffset >> 3 ) + 1 ) >> ( 8 - ( readOffsetMod8 ) ); // Second half (overlaps byte boundary)

                if (numberOfBitsToRead>=8)
                {
                        numberOfBitsToRead -= 8;
                        readOffset += 8;
                        offset++;
                }
                else
                {
                        int neg = (int) numberOfBitsToRead - 8;

                        if ( neg < 0 )   // Reading a partial byte for the last byte, shift right so the data is aligned on the right
                        {

                                if ( alignBitsToRight )
                                        * ( inOutByteArray + offset ) >>= -neg;

                                readOffset += 8 + neg;
                        }
                        else
                                readOffset += 8;

                        offset++;

                        numberOfBitsToRead=0;
                }               
        }

        return true;
}

// Assume the input source points to a compressed native type. Decompress and read it
bool BitStream::ReadCompressed( unsigned char* inOutByteArray,
                                                           const unsigned int size, const bool unsignedData )
{
        unsigned int currentByte = ( size >> 3 ) - 1;


        unsigned char byteMatch, halfByteMatch;

        if ( unsignedData )
        {
                byteMatch = 0;
                halfByteMatch = 0;
        }

        else
        {
                byteMatch = 0xFF;
                halfByteMatch = 0xF0;
        }

        // Upper bytes are specified with a single 1 if they match byteMatch
        // From high byte to low byte, if high byte is a byteMatch then write a 1 bit. Otherwise write a 0 bit and then write the remaining bytes
        while ( currentByte > 0 )
        {
                // If we read a 1 then the data is byteMatch.

                bool b;

                if ( Read( b ) == false )
                        return false;

                if ( b )   // Check that bit
                {
                        inOutByteArray[ currentByte ] = byteMatch;
                        currentByte--;
                }
                else
                {
                        // Read the rest of the bytes

                        if ( ReadBits( inOutByteArray, ( currentByte + 1 ) << 3 ) == false )
                                return false;

                        return true;
                }
        }

        // All but the first bytes are byteMatch.  If the upper half of the last byte is a 0 (positive) or 16 (negative) then what we read will be a 1 and the remaining 4 bits.
        // Otherwise we read a 0 and the 8 bytes
        //RakAssert(readOffset+1 <=numberOfBitsUsed); // If this assert is hit the stream wasn't long enough to read from
        if ( readOffset + 1 > numberOfBitsUsed )
                return false;

        bool b;

        if ( Read( b ) == false )
                return false;

        if ( b )   // Check that bit
        {

                if ( ReadBits( inOutByteArray + currentByte, 4 ) == false )
                        return false;

                inOutByteArray[ currentByte ] |= halfByteMatch; // We have to set the high 4 bits since these are set to 0 by ReadBits
        }
        else
        {
                if ( ReadBits( inOutByteArray + currentByte, 8 ) == false )
                        return false;
        }

        return true;
}

// Reallocates (if necessary) in preparation of writing numberOfBitsToWrite
void BitStream::AddBitsAndReallocate( const BitSize_t numberOfBitsToWrite )
{
        BitSize_t newNumberOfBitsAllocated = numberOfBitsToWrite + numberOfBitsUsed;

        if ( numberOfBitsToWrite + numberOfBitsUsed > 0 && ( ( numberOfBitsAllocated - 1 ) >> 3 ) < ( ( newNumberOfBitsAllocated - 1 ) >> 3 ) )   // If we need to allocate 1 or more new bytes
        {
#ifdef _DEBUG
                // If this assert hits then we need to specify true for the third parameter in the constructor
                // It needs to reallocate to hold all the data and can't do it unless we allocated to begin with
                // Often hits if you call Write or Serialize on a read-only bitstream
                RakAssert( copyData == true );
#endif

                // Less memory efficient but saves on news and deletes
                newNumberOfBitsAllocated = ( numberOfBitsToWrite + numberOfBitsUsed ) * 2;
                if (newNumberOfBitsAllocated - ( numberOfBitsToWrite + numberOfBitsUsed ) > 1048576 )
                        newNumberOfBitsAllocated = numberOfBitsToWrite + numberOfBitsUsed + 1048576;

                //              BitSize_t newByteOffset = BITS_TO_BYTES( numberOfBitsAllocated );
                // Use realloc and free so we are more efficient than delete and new for resizing
                BitSize_t amountToAllocate = BITS_TO_BYTES( newNumberOfBitsAllocated );
                if (data==(unsigned char*)stackData)
                {
                        if (amountToAllocate > BITSTREAM_STACK_ALLOCATION_SIZE)
                        {
                                data = ( unsigned char* ) rakMalloc_Ex( (size_t) amountToAllocate, __FILE__, __LINE__ );

                                // need to copy the stack data over to our new memory area too
                                memcpy ((void *)data, (void *)stackData, (size_t) BITS_TO_BYTES( numberOfBitsAllocated )); 
                        }
                }
                else
                {
                        data = ( unsigned char* ) rakRealloc_Ex( data, (size_t) amountToAllocate, __FILE__, __LINE__ );
                }

#ifdef _DEBUG
                RakAssert( data ); // Make sure realloc succeeded
#endif
                //  memset(data+newByteOffset, 0,  ((newNumberOfBitsAllocated-1)>>3) - ((numberOfBitsAllocated-1)>>3)); // Set the new data block to 0
        }

        if ( newNumberOfBitsAllocated > numberOfBitsAllocated )
                numberOfBitsAllocated = newNumberOfBitsAllocated;
}
BitSize_t BitStream::GetNumberOfBitsAllocated(void) const
{
        return numberOfBitsAllocated;
}
void BitStream::PadWithZeroToByteLength( unsigned int bytes )
{
        if (GetNumberOfBytesUsed() < bytes)
        {
                AlignWriteToByteBoundary();
                unsigned int numToWrite = bytes - GetNumberOfBytesUsed();
                AddBitsAndReallocate( BYTES_TO_BITS(numToWrite) );
                memset(data+BITS_TO_BYTES(numberOfBitsUsed), 0, (size_t) numToWrite);
                numberOfBitsUsed+=BYTES_TO_BITS(numToWrite);
        }
}

/* 
// Julius Goryavsky's version of Harley's algorithm.
// 17 elementary ops plus an indexed load, if the machine
// has "and not."

int nlz10b(unsigned x) {

   static char table[64] =
     {32,20,19, u, u,18, u, 7,  10,17, u, u,14, u, 6, u,
       u, 9, u,16, u, u, 1,26,   u,13, u, u,24, 5, u, u,
       u,21, u, 8,11, u,15, u,   u, u, u, 2,27, 0,25, u,
      22, u,12, u, u, 3,28, u,  23, u, 4,29, u, u,30,31};

   x = x | (x >> 1);    // Propagate leftmost
   x = x | (x >> 2);    // 1-bit to the right.
   x = x | (x >> 4);
   x = x | (x >> 8);
   x = x & ~(x >> 16);
   x = x*0xFD7049FF;    // Activate this line or the following 3.
// x = (x << 9) - x;    // Multiply by 511.
// x = (x << 11) - x;   // Multiply by 2047.
// x = (x << 14) - x;   // Multiply by 16383.
   return table[x >> 26];
}
*/
int BitStream::NumberOfLeadingZeroes( int8_t x ) {return NumberOfLeadingZeroes((uint8_t)x);}
int BitStream::NumberOfLeadingZeroes( uint8_t x )
{
        uint8_t y;
        int n;

        n = 8;
        y = x >> 4;  if (y != 0) {n = n - 4;  x = y;}
        y = x >> 2;  if (y != 0) {n = n - 2;  x = y;}
        y = x >> 1;  if (y != 0) return n - 2;
        return (int)(n - x);
}
int BitStream::NumberOfLeadingZeroes( int16_t x ) {return NumberOfLeadingZeroes((uint16_t)x);}
int BitStream::NumberOfLeadingZeroes( uint16_t x )
{
        uint16_t y;
        int n;

        n = 16;
        y = x >> 8;  if (y != 0) {n = n - 8;  x = y;}
        y = x >> 4;  if (y != 0) {n = n - 4;  x = y;}
        y = x >> 2;  if (y != 0) {n = n - 2;  x = y;}
        y = x >> 1;  if (y != 0) return n - 2;
        return (int)(n - x);
}
int BitStream::NumberOfLeadingZeroes( int32_t x ) {return NumberOfLeadingZeroes((uint32_t)x);}
int BitStream::NumberOfLeadingZeroes( uint32_t x )
{
        uint32_t y;
        int n;

        n = 32;
        y = x >>16;  if (y != 0) {n = n -16;  x = y;}
        y = x >> 8;  if (y != 0) {n = n - 8;  x = y;}
        y = x >> 4;  if (y != 0) {n = n - 4;  x = y;}
        y = x >> 2;  if (y != 0) {n = n - 2;  x = y;}
        y = x >> 1;  if (y != 0) return n - 2;
        return (int)(n - x);
}
int BitStream::NumberOfLeadingZeroes( int64_t x ) {return NumberOfLeadingZeroes((uint64_t)x);}
int BitStream::NumberOfLeadingZeroes( uint64_t x )
{
        uint64_t y;
        int n;

        n = 64;
        y = x >>32;  if (y != 0) {n = n -32;  x = y;}
        y = x >>16;  if (y != 0) {n = n -16;  x = y;}
        y = x >> 8;  if (y != 0) {n = n - 8;  x = y;}
        y = x >> 4;  if (y != 0) {n = n - 4;  x = y;}
        y = x >> 2;  if (y != 0) {n = n - 2;  x = y;}
        y = x >> 1;  if (y != 0) return n - 2;
        return (int)(n - x);
}

// Should hit if reads didn't match writes
void BitStream::AssertStreamEmpty( void )
{
        RakAssert( readOffset == numberOfBitsUsed );
}
void BitStream::PrintBits( char *out ) const
{
        if ( numberOfBitsUsed <= 0 )
        {
                strcpy(out, "No bits\n" );
                return;
        }

        unsigned int strIndex=0;
        for ( BitSize_t counter = 0; counter < BITS_TO_BYTES( numberOfBitsUsed ); counter++ )
        {
                BitSize_t stop;

                if ( counter == ( numberOfBitsUsed - 1 ) >> 3 )
                        stop = 8 - ( ( ( numberOfBitsUsed - 1 ) & 7 ) + 1 );
                else
                        stop = 0;

                for ( BitSize_t counter2 = 7; counter2 >= stop; counter2-- )
                {
                        if ( ( data[ counter ] >> counter2 ) & 1 )
                                out[strIndex++]='1';
                        else
                                out[strIndex++]='0';

                        if (counter2==0)
                                break;
                }

                out[strIndex++]=' ';
        }

        out[strIndex++]='\n';

        out[strIndex++]=0;
}
void BitStream::PrintBits( void ) const
{
        char out[2048];
        PrintBits(out);
        RAKNET_DEBUG_PRINTF(out);
}
void BitStream::PrintHex( char *out ) const
{
        BitSize_t i;
        for ( i=0; i < GetNumberOfBytesUsed(); i++)
        {
                sprintf(out+i*3, "%02x ", data[i]);
        }
}
void BitStream::PrintHex( void ) const
{
        char out[2048];
        PrintHex(out);
        RAKNET_DEBUG_PRINTF(out);
}

// Exposes the data for you to look at, like PrintBits does.
// Data will point to the stream.  Returns the length in bits of the stream.
BitSize_t BitStream::CopyData( unsigned char** _data ) const
{
#ifdef _DEBUG
        RakAssert( numberOfBitsUsed > 0 );
#endif

        *_data = (unsigned char*) rakMalloc_Ex( (size_t) BITS_TO_BYTES( numberOfBitsUsed ), __FILE__, __LINE__ );
        memcpy( *_data, data, sizeof(unsigned char) * (size_t) ( BITS_TO_BYTES( numberOfBitsUsed ) ) );
        return numberOfBitsUsed;
}

// Ignore data we don't intend to read
void BitStream::IgnoreBits( const BitSize_t numberOfBits )
{
        readOffset += numberOfBits;
}

void BitStream::IgnoreBytes( const unsigned int numberOfBytes )
{
        IgnoreBits(BYTES_TO_BITS(numberOfBytes));
}

// Move the write pointer to a position on the array.  Dangerous if you don't know what you are doing!
// Doesn't work with non-aligned data!
void BitStream::SetWriteOffset( const BitSize_t offset )
{
        numberOfBitsUsed = offset;
}

/*
BitSize_t BitStream::GetWriteOffset( void ) const
{
return numberOfBitsUsed;
}

// Returns the length in bits of the stream
BitSize_t BitStream::GetNumberOfBitsUsed( void ) const
{
return GetWriteOffset();
}

// Returns the length in bytes of the stream
BitSize_t BitStream::GetNumberOfBytesUsed( void ) const
{
return BITS_TO_BYTES( numberOfBitsUsed );
}

// Returns the number of bits into the stream that we have read
BitSize_t BitStream::GetReadOffset( void ) const
{
return readOffset;
}


// Sets the read bit index
void BitStream::SetReadOffset( const BitSize_t newReadOffset )
{
readOffset=newReadOffset;
}

// Returns the number of bits left in the stream that haven't been read
BitSize_t BitStream::GetNumberOfUnreadBits( void ) const
{
return numberOfBitsUsed - readOffset;
}
// Exposes the internal data
unsigned char* BitStream::GetData( void ) const
{
return data;
}

*/
// If we used the constructor version with copy data off, this makes sure it is set to on and the data pointed to is copied.
void BitStream::AssertCopyData( void )
{
        if ( copyData == false )
        {
                copyData = true;

                if ( numberOfBitsAllocated > 0 )
                {
                        unsigned char * newdata = ( unsigned char* ) rakMalloc_Ex( (size_t) BITS_TO_BYTES( numberOfBitsAllocated ), __FILE__, __LINE__ );
#ifdef _DEBUG

                        RakAssert( data );
#endif

                        memcpy( newdata, data, (size_t) BITS_TO_BYTES( numberOfBitsAllocated ) );
                        data = newdata;
                }

                else
                        data = 0;
        }
}
bool BitStream::IsNetworkOrderInternal(void)
{
#if defined(_PS3) || defined(__PS3__) || defined(SN_TARGET_PS3)
             
#else
        static const bool isNetworkOrder=(htonl(12345) == 12345);
        return isNetworkOrder;
#endif
}
void BitStream::ReverseBytes(unsigned char *inByteArray, unsigned char *inOutByteArray, const unsigned int length)
{
        for (BitSize_t i=0; i < length; i++)
                inOutByteArray[i]=inByteArray[length-i-1];
}
void BitStream::ReverseBytesInPlace(unsigned char *inOutData,const unsigned int length)
{
        unsigned char temp;
        BitSize_t i;
        for (i=0; i < (length>>1); i++)
        {
                temp = inOutData[i];
                inOutData[i]=inOutData[length-i-1];
                inOutData[length-i-1]=temp;
        }
}

bool BitStream::Read(char *varString)
{
        return RakString::Deserialize(varString,this);
}
bool BitStream::Read(unsigned char *varString)
{
        return RakString::Deserialize((char*) varString,this);
}
void BitStream::WriteAlignedVar8(const char *inByteArray)
{
        RakAssert((numberOfBitsUsed&7)==0);
        AddBitsAndReallocate(1*8);
        data[( numberOfBitsUsed >> 3 ) + 0] = inByteArray[0];
        numberOfBitsUsed+=1*8;
}
bool BitStream::ReadAlignedVar8(char *inOutByteArray)
{
        RakAssert((readOffset&7)==0);
        if ( readOffset + 1*8 > numberOfBitsUsed )
                return false;

        inOutByteArray[0] = data[( readOffset >> 3 ) + 0];
        readOffset+=1*8;
        return true;
}
void BitStream::WriteAlignedVar16(const char *inByteArray)
{
        RakAssert((numberOfBitsUsed&7)==0);
        AddBitsAndReallocate(2*8);
#ifndef __BITSTREAM_NATIVE_END
        if (DoEndianSwap())
        {
                data[( numberOfBitsUsed >> 3 ) + 0] = inByteArray[1];
                data[( numberOfBitsUsed >> 3 ) + 1] = inByteArray[0];
        }
        else
#endif
        {
                data[( numberOfBitsUsed >> 3 ) + 0] = inByteArray[0];
                data[( numberOfBitsUsed >> 3 ) + 1] = inByteArray[1];
        }

        numberOfBitsUsed+=2*8;
}
bool BitStream::ReadAlignedVar16(char *inOutByteArray)
{
        RakAssert((readOffset&7)==0);
        if ( readOffset + 2*8 > numberOfBitsUsed )
                return false;
#ifndef __BITSTREAM_NATIVE_END
        if (DoEndianSwap())
        {
                inOutByteArray[0] = data[( readOffset >> 3 ) + 1];
                inOutByteArray[1] = data[( readOffset >> 3 ) + 0];
        }
        else
#endif
        {
                inOutByteArray[0] = data[( readOffset >> 3 ) + 0];
                inOutByteArray[1] = data[( readOffset >> 3 ) + 1];
        }

        readOffset+=2*8;
        return true;
}
void BitStream::WriteAlignedVar32(const char *inByteArray)
{
        RakAssert((numberOfBitsUsed&7)==0);
        AddBitsAndReallocate(4*8);
#ifndef __BITSTREAM_NATIVE_END
        if (DoEndianSwap())
        {
                data[( numberOfBitsUsed >> 3 ) + 0] = inByteArray[3];
                data[( numberOfBitsUsed >> 3 ) + 1] = inByteArray[2];
                data[( numberOfBitsUsed >> 3 ) + 2] = inByteArray[1];
                data[( numberOfBitsUsed >> 3 ) + 3] = inByteArray[0];
        }
        else
#endif
        {
                data[( numberOfBitsUsed >> 3 ) + 0] = inByteArray[0];
                data[( numberOfBitsUsed >> 3 ) + 1] = inByteArray[1];
                data[( numberOfBitsUsed >> 3 ) + 2] = inByteArray[2];
                data[( numberOfBitsUsed >> 3 ) + 3] = inByteArray[3];
        }

        numberOfBitsUsed+=4*8;
}
bool BitStream::ReadAlignedVar32(char *inOutByteArray)
{
        RakAssert((readOffset&7)==0);
        if ( readOffset + 4*8 > numberOfBitsUsed )
                return false;
#ifndef __BITSTREAM_NATIVE_END
        if (DoEndianSwap())
        {
                inOutByteArray[0] = data[( readOffset >> 3 ) + 3];
                inOutByteArray[1] = data[( readOffset >> 3 ) + 2];
                inOutByteArray[2] = data[( readOffset >> 3 ) + 1];
                inOutByteArray[3] = data[( readOffset >> 3 ) + 0];
        }
        else
#endif
        {
                inOutByteArray[0] = data[( readOffset >> 3 ) + 0];
                inOutByteArray[1] = data[( readOffset >> 3 ) + 1];
                inOutByteArray[2] = data[( readOffset >> 3 ) + 2];
                inOutByteArray[3] = data[( readOffset >> 3 ) + 3];
        }

        readOffset+=4*8;
        return true;
}
bool BitStream::ReadFloat16( float &outFloat, float floatMin, float floatMax )
{
        unsigned short percentile;
        if (Read(percentile))
        {
                RakAssert(floatMax>floatMin);
                outFloat = floatMin + ((float) percentile / 65535.0f) * (floatMax-floatMin);
                if (outFloat<floatMin)
                        outFloat=floatMin;
                else if (outFloat>floatMax)
                        outFloat=floatMax;
                return true;
        }
        return false;
}
bool BitStream::SerializeFloat16(bool writeToBitstream, float &inOutFloat, float floatMin, float floatMax)
{
        if (writeToBitstream)
                WriteFloat16(inOutFloat, floatMin, floatMax);
        else
                return ReadFloat16(inOutFloat, floatMin, floatMax);
        return true;
}
void BitStream::WriteFloat16( float inOutFloat, float floatMin, float floatMax )
{
        RakAssert(floatMax>floatMin);
        if (inOutFloat>floatMax+.001)
        {
                RakAssert(inOutFloat<=floatMax+.001);
        }
        if (inOutFloat<floatMin-.001)
        {
                RakAssert(inOutFloat>=floatMin-.001);
        }
        float percentile=65535.0f * (inOutFloat-floatMin)/(floatMax-floatMin);
        if (percentile<0.0)
                percentile=0.0;
        if (percentile>65535.0f)
                percentile=65535.0f;
        Write((unsigned short)percentile);
}

#ifdef _MSC_VER
#pragma warning( pop )
#endif

#endif // #if _MSC_VER < 1299