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#include "LZSS.h"
#include <stdlib.h>
#include <string.h>
bool InitializeLZSS(LZSS *self,int windowsize)
{
self->window=malloc(windowsize);
if(!self->window) return false;
self->mask=windowsize-1; // Assume windows are power-of-two sized!
RestartLZSS(self);
return true;
}
void CleanupLZSS(LZSS *self)
{
free(self->window);
}
void RestartLZSS(LZSS *self)
{
memset(self->window,0,LZSSWindowSize(self));
self->position=0;
}
void CopyBytesFromLZSSWindow(LZSS *self,uint8_t *buffer,int64_t startpos,int length)
{
int windowoffs=LZSSWindowOffsetForPosition(self,startpos);
if(windowoffs+length<=LZSSWindowSize(self)) // Request fits inside window
{
memcpy(buffer,&self->window[windowoffs],length);
}
else // Request wraps around window
{
int firstpart=LZSSWindowSize(self)-windowoffs;
memcpy(&buffer[0],&self->window[windowoffs],firstpart);
memcpy(&buffer[firstpart],&self->window[0],length-firstpart);
}
}
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