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#import "XADRARInputHandle.h"
#import "XADException.h"
#import "CRC.h"
@implementation XADRARInputHandle
-(id)initWithRARParser:(XADRARParser *)parent parts:(NSArray *)partarray
{
off_t totallength=0;
NSEnumerator *enumerator=[partarray objectEnumerator];
NSDictionary *dict;
while((dict=[enumerator nextObject]))
{
totallength+=[[dict objectForKey:@"InputLength"] longLongValue];
}
if((self=[super initWithName:[parent filename] length:totallength]))
{
parser=parent;
parts=[partarray retain];
}
return self;
}
-(void)dealloc
{
[parts release];
[super dealloc];
}
-(void)resetStream
{
part=0;
partend=0;
[self startNextPart];
}
-(int)streamAtMost:(int)num toBuffer:(void *)buffer
{
CSHandle *fh=[parser handle];
uint8_t *bytebuf=buffer;
int total=0;
while(total<num)
{
if(streampos+total>=partend) [self startNextPart];
int numbytes=num-total;
if(streampos+total+numbytes>=partend) numbytes=partend-streampos-total;
[fh readBytes:numbytes toBuffer:&bytebuf[total]];
crc=XADCalculateCRC(crc,&bytebuf[total],numbytes,XADCRCTable_edb88320);
total+=numbytes;
if(streampos+total>=partend)
if(partend!=streamlength)
if(correctcrc!=0xffffffff)
if(~crc!=correctcrc)
[XADException raiseChecksumException];
}
return num;
}
-(void)startNextPart
{
if(part>=[parts count]) [XADException raiseInputException];
NSDictionary *dict=[parts objectAtIndex:part];
part++;
off_t offset=[[dict objectForKey:@"Offset"] longLongValue];
off_t length=[[dict objectForKey:@"InputLength"] longLongValue];
[[parser handle] seekToFileOffset:offset];
partend+=length;
crc=0xffffffff;
correctcrc=[[dict objectForKey:@"CRC32"] unsignedIntValue];
}
@end
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