XADMaster/XADStuffItHuffmanHandle.m
2018-03-21 14:24:50 +02:00

75 lines
1.7 KiB
Objective-C

/*
* XADStuffItHuffmanHandle.m
*
* Copyright (c) 2017-present, MacPaw Inc. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA
*/
#import "XADStuffItHuffmanHandle.h"
@implementation XADStuffItHuffmanHandle
-(id)initWithHandle:(CSHandle *)handle
{
return [self initWithHandle:handle length:CSHandleMaxLength];
}
-(id)initWithHandle:(CSHandle *)handle length:(off_t)length
{
if((self=[super initWithInputBufferForHandle:handle length:length]))
{
code=nil;
}
return self;
}
-(void)dealloc
{
[code release];
[super dealloc];
}
-(void)resetByteStream
{
[code release];
code=[XADPrefixCode new];
[code startBuildingTree];
[self parseTree];
}
-(void)parseTree
{
if(CSInputNextBit(input)==1)
{
[code makeLeafWithValue:CSInputNextBitString(input,8)];
}
else
{
[code startZeroBranch];
[self parseTree];
[code startOneBranch];
[self parseTree];
[code finishBranches];
}
}
-(uint8_t)produceByteAtOffset:(off_t)pos
{
return CSInputNextSymbolUsingCode(input,code);
}
@end