DarkflameServer/thirdparty/raknet/Source/DS_ByteQueue.cpp

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#include "DS_ByteQueue.h"
#include <string.h> // Memmove
#include <stdlib.h> // realloc
#include <stdio.h>
using namespace DataStructures;
ByteQueue::ByteQueue()
{
readOffset=writeOffset=lengthAllocated=0;
data=0;
}
ByteQueue::~ByteQueue()
{
Clear();
}
void ByteQueue::WriteBytes(const char *in, unsigned length)
{
unsigned bytesWritten;
bytesWritten=GetBytesWritten();
if (lengthAllocated==0 || length > lengthAllocated-bytesWritten-1)
{
unsigned oldLengthAllocated=lengthAllocated;
unsigned newAmountToAllocate=length*2;
if (newAmountToAllocate<256)
newAmountToAllocate=256;
lengthAllocated=lengthAllocated + newAmountToAllocate;
data=(char*)rakRealloc(data, lengthAllocated);
if (writeOffset < readOffset)
{
if (writeOffset <= newAmountToAllocate)
{
memcpy(data + oldLengthAllocated, data, writeOffset);
writeOffset=readOffset+bytesWritten;
}
else
{
memcpy(data + oldLengthAllocated, data, newAmountToAllocate);
memmove(data, data+newAmountToAllocate, writeOffset-newAmountToAllocate);
writeOffset-=newAmountToAllocate;
}
}
}
if (length <= lengthAllocated-writeOffset)
memcpy(data+writeOffset, in, length);
else
{
// Wrap
memcpy(data+writeOffset, in, lengthAllocated-writeOffset);
memcpy(data, in+(lengthAllocated-writeOffset), length-(lengthAllocated-writeOffset));
}
writeOffset=(writeOffset+length) % lengthAllocated;
}
bool ByteQueue::ReadBytes(char *out, unsigned length, bool peek)
{
if (GetBytesWritten() < length)
return false;
if (length <= lengthAllocated-readOffset)
memcpy(out, data+readOffset, length);
else
{
// Wrap
memcpy(out, data+readOffset, lengthAllocated-readOffset);
memcpy(out+(lengthAllocated-readOffset), data, length-(lengthAllocated-readOffset));
}
if (peek==false)
IncrementReadOffset(length);
return true;
}
void ByteQueue::Clear(void)
{
if (lengthAllocated)
rakFree(data);
readOffset=writeOffset=lengthAllocated=0;
data=0;
}
unsigned ByteQueue::GetBytesWritten(void) const
{
if (writeOffset>=readOffset)
return writeOffset-readOffset;
else
return (writeOffset-1)+(lengthAllocated-readOffset);
}
void ByteQueue::IncrementReadOffset(unsigned length)
{
readOffset=(readOffset+length) % lengthAllocated;
}
void ByteQueue::Print(void)
{
unsigned i;
for (i=readOffset; i!=writeOffset; i++)
printf("%i ", data[i]);
printf("\n");
}