/// \file /// /// This file is part of RakNet Copyright 2003 Kevin Jenkins. /// /// Usage of RakNet is subject to the appropriate license agreement. /// Creative Commons Licensees are subject to the /// license found at /// http://creativecommons.org/licenses/by-nc/2.5/ /// Single application licensees are subject to the license found at /// http://www.rakkarsoft.com/SingleApplicationLicense.html /// Custom license users are subject to the terms therein. /// GPL license users are subject to the GNU General Public /// License as published by the Free /// Software Foundation; either version 2 of the License, or (at your /// option) any later version. #if defined(_MSC_VER) && _MSC_VER < 1299 // VC6 doesn't support template specialization #include "BitStream_NoTemplate.cpp" #else #include "BitStream.h" #include #include #include #include #include #include #ifdef _COMPATIBILITY_1 #include "Compatibility1Includes.h" #elif defined(_WIN32) #include // htonl #else #include #endif // Was included for memset which now comes from string.h instead /* #if defined ( __APPLE__ ) || defined ( __APPLE_CC__ ) #include #elif !defined(_COMPATIBILITY_2) #include #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* ) malloc( 32 ); data = ( unsigned char* ) stackData; #ifdef _DEBUG // assert( data ); #endif //memset(data, 0, 32); copyData = true; } BitStream::BitStream( 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* ) malloc( initialBytesToAllocate ); numberOfBitsAllocated = initialBytesToAllocate << 3; } #ifdef _DEBUG assert( data ); #endif // memset(data, 0, initialBytesToAllocate); copyData = true; } BitStream::BitStream( unsigned char* _data, 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* ) malloc( lengthInBytes ); } #ifdef _DEBUG assert( data ); #endif memcpy( data, _data, lengthInBytes ); } else data = 0; } else data = ( unsigned char* ) _data; } // SAMPSRV (adding this just as a tag for next RakNet upgrade) BitStream::BitStream( char* _dataC, unsigned int lengthInBytes, bool _copyData ) { unsigned char* _data = reinterpret_cast(_dataC); 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* ) malloc( lengthInBytes ); } #ifdef _DEBUG assert( data ); #endif memcpy( data, _data, lengthInBytes ); } else data = 0; } else data = ( unsigned char* ) _data; } // SAMPSRV end // Use this if you pass a pointer copy to the constructor (_copyData==false) and want to overallocate to prevent reallocation void BitStream::SetNumberOfBitsAllocated( const unsigned int lengthInBits ) { #ifdef _DEBUG assert( lengthInBits >= ( unsigned int ) numberOfBitsAllocated ); #endif numberOfBitsAllocated = lengthInBits; } BitStream::~BitStream() { if ( copyData && numberOfBitsAllocated > BITSTREAM_STACK_ALLOCATION_SIZE << 3) free( data ); // 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*)malloc(1); // if (numberOfBitsAllocated>0) // memset(data, 0, BITS_TO_BYTES(numberOfBitsAllocated)); } // Write an array or casted stream void BitStream::Write( const char* input, const int numberOfBytes ) { if (numberOfBytes==0 || input==0) return; // Optimization: if ((numberOfBitsUsed & 7) == 0) { AddBitsAndReallocate( BYTES_TO_BITS(numberOfBytes) ); memcpy(data+BITS_TO_BYTES(numberOfBitsUsed), input, numberOfBytes); numberOfBitsUsed+=BYTES_TO_BITS(numberOfBytes); } else { WriteBits( ( unsigned char* ) input, numberOfBytes * 8, true ); } } void BitStream::Write( BitStream *bitStream) { Write(bitStream, bitStream->GetNumberOfBitsUsed()); } void BitStream::Write( BitStream *bitStream, int numberOfBits ) { AddBitsAndReallocate( numberOfBits ); int numberOfBitsMod8; 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++ % 8 ) ) ) { // 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++ % 8 ) ) ) data[ numberOfBitsUsed >> 3 ] |= 0x80 >> ( numberOfBitsMod8 ); // Set the bit to 1 // else 0, do nothing } numberOfBitsUsed++; } } // Read an array or casted stream bool BitStream::Read( char* output, const int numberOfBytes ) { // Optimization: if ((readOffset & 7) == 0) { if ( readOffset + ( numberOfBytes << 3 ) > numberOfBitsUsed ) return false; // Write the data memcpy( output, data + ( readOffset >> 3 ), numberOfBytes ); readOffset += numberOfBytes << 3; return true; } else { return ReadBits( ( unsigned char* ) output, 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 ); int numberOfBitsMod8 = numberOfBitsUsed & 7; if ( numberOfBitsMod8 == 0 ) data[ numberOfBitsUsed >> 3 ] = 0x80; else data[ numberOfBitsUsed >> 3 ] |= 0x80 >> ( numberOfBitsMod8 ); // Set the bit to 1 numberOfBitsUsed++; } #ifdef _MSC_VER #pragma warning( disable : 4800 ) // warning C4100: : unreferenced formal parameter #endif // Returns true if the next data read is a 1, false if it is a 0 bool BitStream::ReadBit( void ) { return ( bool ) ( data[ readOffset >> 3 ] & ( 0x80 >> ( readOffset++ & 7 ) ) ); } // 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* input, const int numberOfBytesToWrite ) { #ifdef _DEBUG assert( numberOfBytesToWrite > 0 ); #endif AlignWriteToByteBoundary(); Write((const char*) input, numberOfBytesToWrite); } // 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* output, const int numberOfBytesToRead ) { #ifdef _DEBUG assert( numberOfBytesToRead > 0 ); #endif if ( numberOfBytesToRead <= 0 ) return false; // Byte align AlignReadToByteBoundary(); if ( readOffset + ( numberOfBytesToRead << 3 ) > numberOfBitsUsed ) return false; // Write the data memcpy( output, data + ( readOffset >> 3 ), numberOfBytesToRead ); readOffset += numberOfBytesToRead << 3; return true; } // Align the next write and/or read to a byte boundary. This can be used to 'waste' bits to byte align for efficiency reasons void BitStream::AlignWriteToByteBoundary( void ) { if ( numberOfBitsUsed ) numberOfBitsUsed += 8 - ( (( numberOfBitsUsed - 1 ) & 7) + 1 ); } // Align the next write and/or read to a byte boundary. This can be used to 'waste' bits to byte align for efficiency reasons void BitStream::AlignReadToByteBoundary( void ) { if ( readOffset ) readOffset += 8 - ( (( readOffset - 1 ) & 7 ) + 1 ); } // Write numberToWrite bits from the input source void BitStream::WriteBits( const unsigned char *input, int numberOfBitsToWrite, const bool rightAlignedBits ) { if (numberOfBitsToWrite<=0) return; AddBitsAndReallocate( numberOfBitsToWrite ); int offset = 0; unsigned char dataByte; int numberOfBitsUsedMod8; numberOfBitsUsedMod8 = numberOfBitsUsed & 7; // Faster to put the while at the top surprisingly enough while ( numberOfBitsToWrite > 0 ) //do { dataByte = *( input + offset ); 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; else numberOfBitsUsed += numberOfBitsToWrite; numberOfBitsToWrite -= 8; offset++; } // } while(numberOfBitsToWrite>0); } // Set the stream to some initial data. For internal use void BitStream::SetData( unsigned char *input ) { data=input; copyData=false; } // Assume the input source points to a native type, compress and write it void BitStream::WriteCompressed( const unsigned char* input, const int size, const bool unsignedData ) { int 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 ( input[ 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( input, ( 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 && ( ( *( input + currentByte ) ) & 0xF0 ) == 0x00 ) || ( unsignedData == false && ( ( *( input + currentByte ) ) & 0xF0 ) == 0xF0 ) ) { bool b = true; Write( b ); WriteBits( input + currentByte, 4, true ); } else { bool b = false; Write( b ); WriteBits( input + 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* output, int numberOfBitsToRead, const bool alignBitsToRight ) { #ifdef _DEBUG assert( numberOfBitsToRead > 0 ); #endif if (numberOfBitsToRead<=0) return false; if ( readOffset + numberOfBitsToRead > numberOfBitsUsed ) return false; int readOffsetMod8; int offset = 0; memset( output, 0, BITS_TO_BYTES( numberOfBitsToRead ) ); readOffsetMod8 = readOffset & 7; // do // Faster to put the while at the top surprisingly enough while ( numberOfBitsToRead > 0 ) { *( output + 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 *( output + offset ) |= *( data + ( readOffset >> 3 ) + 1 ) >> ( 8 - ( readOffsetMod8 ) ); // Second half (overlaps byte boundary) numberOfBitsToRead -= 8; if ( numberOfBitsToRead < 0 ) // Reading a partial byte for the last byte, shift right so the data is aligned on the right { if ( alignBitsToRight ) * ( output + offset ) >>= -numberOfBitsToRead; readOffset += 8 + numberOfBitsToRead; } else readOffset += 8; offset++; } //} while(numberOfBitsToRead>0); return true; } // Assume the input source points to a compressed native type. Decompress and read it bool BitStream::ReadCompressed( unsigned char* output, const int size, const bool unsignedData ) { 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 { output[ currentByte ] = byteMatch; currentByte--; } else { // Read the rest of the bytes if ( ReadBits( output, ( 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 //assert(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( output + currentByte, 4 ) == false ) return false; output[ currentByte ] |= halfByteMatch; // We have to set the high 4 bits since these are set to 0 by ReadBits } else { if ( ReadBits( output + currentByte, 8 ) == false ) return false; } return true; } // Reallocates (if necessary) in preparation of writing numberOfBitsToWrite void BitStream::AddBitsAndReallocate( const int numberOfBitsToWrite ) { if (numberOfBitsToWrite <= 0) return; int 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 assert( copyData == true ); #endif // Less memory efficient but saves on news and deletes newNumberOfBitsAllocated = ( numberOfBitsToWrite + numberOfBitsUsed ) * 2; // int newByteOffset = BITS_TO_BYTES( numberOfBitsAllocated ); // Use realloc and free so we are more efficient than delete and new for resizing int amountToAllocate = BITS_TO_BYTES( newNumberOfBitsAllocated ); if (data==(unsigned char*)stackData) { if (amountToAllocate > BITSTREAM_STACK_ALLOCATION_SIZE) { data = ( unsigned char* ) malloc( amountToAllocate ); // need to copy the stack data over to our new memory area too memcpy ((void *)data, (void *)stackData, BITS_TO_BYTES( numberOfBitsAllocated )); } } else { data = ( unsigned char* ) realloc( data, amountToAllocate ); } #ifdef _DEBUG assert( 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; } // Should hit if reads didn't match writes void BitStream::AssertStreamEmpty( void ) { assert( readOffset == numberOfBitsUsed ); } void BitStream::PrintBits( void ) const { if ( numberOfBitsUsed <= 0 ) { printf( "No bits\n" ); return ; } for ( int counter = 0; counter < BITS_TO_BYTES( numberOfBitsUsed ); counter++ ) { int stop; if ( counter == ( numberOfBitsUsed - 1 ) >> 3 ) stop = 8 - ( ( ( numberOfBitsUsed - 1 ) & 7 ) + 1 ); else stop = 0; for ( int counter2 = 7; counter2 >= stop; counter2-- ) { if ( ( data[ counter ] >> counter2 ) & 1 ) putchar( '1' ); else putchar( '0' ); } putchar( ' ' ); } putchar( '\n' ); } // 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. int BitStream::CopyData( unsigned char** _data ) const { #ifdef _DEBUG assert( numberOfBitsUsed > 0 ); #endif *_data = new unsigned char [ BITS_TO_BYTES( numberOfBitsUsed ) ]; memcpy( *_data, data, sizeof(unsigned char) * ( BITS_TO_BYTES( numberOfBitsUsed ) ) ); return numberOfBitsUsed; } // Ignore data we don't intend to read void BitStream::IgnoreBits( const int numberOfBits ) { readOffset += numberOfBits; } // Move the write pointer to a position on the array. Dangerous if you don't know what you are doing! void BitStream::SetWriteOffset( const int offset ) { numberOfBitsUsed = offset; } /* int BitStream::GetWriteOffset( void ) const { return numberOfBitsUsed; } // Returns the length in bits of the stream int BitStream::GetNumberOfBitsUsed( void ) const { return GetWriteOffset(); } // Returns the length in bytes of the stream int BitStream::GetNumberOfBytesUsed( void ) const { return BITS_TO_BYTES( numberOfBitsUsed ); } // Returns the number of bits into the stream that we have read int BitStream::GetReadOffset( void ) const { return readOffset; } // Sets the read bit index void BitStream::SetReadOffset( int newReadOffset ) { readOffset=newReadOffset; } // Returns the number of bits left in the stream that haven't been read int 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* ) malloc( BITS_TO_BYTES( numberOfBitsAllocated ) ); #ifdef _DEBUG assert( data ); #endif memcpy( newdata, data, BITS_TO_BYTES( numberOfBitsAllocated ) ); data = newdata; } else data = 0; } } void BitStream::ReverseBytes(unsigned char *input, unsigned char *output, int length) { for (int i=0; i < length; i++) output[i]=input[length-i-1]; } bool BitStream::DoEndianSwap(void) const { #ifndef __BITSTREAM_NATIVE_END static bool swap=htonl(12345) == 12345; return swap; #else return false; #endif } #ifdef _MSC_VER #pragma warning( pop ) #endif #endif // #if _MSC_VER < 1299