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#import "XADChecksumHandle.h"
@implementation XADChecksumHandle
-(id)initWithHandle:(CSHandle *)handle length:(off_t)length correctChecksum:(int)correct mask:(int)mask
{
if((self=[super initWithName:[handle name] length:length]))
{
parent=[handle retain];
correctchecksum=correct;
summask=mask;
}
return self;
}
-(void)dealloc
{
[parent release];
[super dealloc];
}
-(void)resetStream
{
[parent seekToFileOffset:0];
checksum=0;
}
-(int)streamAtMost:(int)num toBuffer:(void *)buffer
{
int actual=[parent readAtMost:num toBuffer:buffer];
uint8_t *bytes=buffer;
for(int i=0;i<actual;i++) checksum+=bytes[i];
return actual;
}
-(BOOL)hasChecksum { return YES; }
-(BOOL)isChecksumCorrect
{
return (checksum&summask)==(correctchecksum&summask);
}
-(double)estimatedProgress { return [parent estimatedProgress]; }
@end
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