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#import "XADFastLZSSHandle.h"
// TODO: Seeking
@implementation XADFastLZSSHandle
-(id)initWithName:(NSString *)descname windowSize:(int)windowsize
{
return [self initWithName:descname length:CSHandleMaxLength windowSize:windowsize];
}
-(id)initWithName:(NSString *)descname length:(off_t)length windowSize:(int)windowsize
{
if((self=[super initWithName:descname length:length]))
{
InitializeLZSS(&lzss,windowsize);
}
return self;
}
-(id)initWithHandle:(CSHandle *)handle windowSize:(int)windowsize
{
return [self initWithHandle:handle length:CSHandleMaxLength windowSize:windowsize];
}
-(id)initWithHandle:(CSHandle *)handle length:(off_t)length windowSize:(int)windowsize
{
if((self=[super initWithHandle:handle length:length]))
{
InitializeLZSS(&lzss,windowsize);
}
return self;
}
-(void)dealloc
{
CleanupLZSS(&lzss);
[super dealloc];
}
-(void)resetStream
{
RestartLZSS(&lzss);
[self resetLZSSHandle];
}
-(int)streamAtMost:(int)num toBuffer:(void *)buffer
{
bufferpointer=buffer;
bufferpos=streampos;
bufferend=streampos+num;
XADLZSSFlushToBuffer(self);
if(bufferpos!=bufferend)
{
flushbarrier=LZSSPosition(&lzss)+LZSSWindowSize(&lzss);
[self expandFromPosition:LZSSPosition(&lzss)];
XADLZSSFlushToBuffer(self);
}
return bufferpos-streampos;
}
-(void)resetLZSSHandle {}
-(void)expandFromPosition:(off_t)pos {}
-(void)endLZSSHandle { [self endStream]; }
// TODO: remove usage of bufferpos entirely, it's somewhat redundant.
void XADLZSSFlushToBuffer(XADFastLZSSHandle *self)
{
off_t end=LZSSPosition(&self->lzss);
if(end>self->bufferend) end=self->bufferend;
int available=end-self->bufferpos;
if(available==0) return;
//if(available<0) [XADException raiseUnknownException]; // TODO: better error
CopyBytesFromLZSSWindow(&self->lzss,self->bufferpointer,self->bufferpos,available);
self->bufferpos+=available;
self->bufferpointer+=available;
self->flushbarrier+=available;
}
@end
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