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

100 lines
2.4 KiB
Objective-C

/*
* XADLZMAHandle.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 "XADLZMAHandle.h"
#import "XADException.h"
static void *Alloc(void *p,size_t size) { return malloc(size); }
static void Free(void *p,void *address) { return free(address); }
static ISzAlloc allocator={Alloc,Free};
@implementation XADLZMAHandle
-(id)initWithHandle:(CSHandle *)handle propertyData:(NSData *)propertydata
{
return [self initWithHandle:handle length:CSHandleMaxLength propertyData:propertydata];
}
-(id)initWithHandle:(CSHandle *)handle length:(off_t)length propertyData:(NSData *)propertydata
{
if((self=[super initWithParentHandle:handle length:length]))
{
startoffs=[parent offsetInFile];
LzmaDec_Construct(&lzma);
if(LzmaDec_Allocate(&lzma,[propertydata bytes],[propertydata length],&allocator)==SZ_OK)
{
return self;
}
}
[self release];
return nil;
}
-(void)dealloc
{
LzmaDec_Free(&lzma,&allocator);
[super dealloc];
}
-(void)resetStream
{
[parent seekToFileOffset:startoffs];
LzmaDec_Init(&lzma);
bufbytes=bufoffs=0;
}
-(int)streamAtMost:(int)num toBuffer:(void *)buffer
{
int total=0;
while(total<num)
{
size_t destlen=num-total;
size_t srclen=bufbytes-bufoffs;
ELzmaStatus status;
int res=LzmaDec_DecodeToBuf(&lzma,buffer+total,&destlen,inbuffer+bufoffs,&srclen,LZMA_FINISH_ANY,&status);
total+=destlen;
bufoffs+=srclen;
if(res!=SZ_OK) [XADException raiseDecrunchException];
if(status==LZMA_STATUS_NEEDS_MORE_INPUT)
{
bufbytes=[parent readAtMost:sizeof(inbuffer) toBuffer:inbuffer];
if(!bufbytes) [parent _raiseEOF];
bufoffs=0;
}
else if(status==LZMA_STATUS_FINISHED_WITH_MARK)
{
[self endStream];
break;
}
}
return total;
}
@end