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#import "CSByteStreamHandle.h"
NSString *CSByteStreamEOFReachedException=@"CSByteStreamEOFReachedException";
@implementation CSByteStreamHandle
-(id)initWithName:(NSString *)descname length:(off_t)length
{
if((self=[super initWithName:descname length:length]))
{
bytestreamproducebyte_ptr=(uint8_t (*)(id,SEL,off_t))[self methodForSelector:@selector(produceByteAtOffset:)];
}
return self;
}
-(id)initWithHandle:(CSHandle *)handle length:(off_t)length bufferSize:(int)buffersize;
{
if((self=[super initWithHandle:handle length:length bufferSize:buffersize]))
{
bytestreamproducebyte_ptr=(uint8_t (*)(id,SEL,off_t))[self methodForSelector:@selector(produceByteAtOffset:)];
}
return self;
}
-(id)initAsCopyOf:(CSByteStreamHandle *)other
{
[self _raiseNotSupported:_cmd];
return nil;
}
-(int)streamAtMost:(int)num toBuffer:(void *)buffer
{
bytesproduced=0;
if(setjmp(eofenv)==0)
{
while(bytesproduced<num)
{
uint8_t byte=bytestreamproducebyte_ptr(self,@selector(produceByteAtOffset:),streampos+bytesproduced);
((uint8_t *)buffer)[bytesproduced++]=byte;
if(endofstream) break;
}
}
else
{
[self endStream];
}
return bytesproduced;
}
-(void)resetStream
{
[self resetByteStream];
}
-(void)resetByteStream {}
-(uint8_t)produceByteAtOffset:(off_t)pos { return 0; }
-(void)endByteStream { [self endStream]; }
@end
/*
@implementation CSFilterHandle
-(id)initWithHandle:(CSHandle *)handle
{
if(self=[super initWithName:[handle name]])
{
parent=[handle retain];
readatmost_ptr=(int (*)(id,SEL,int,void *))[parent methodForSelector:@selector(readAtMost:toBuffer:)];
pos=0;
coro=nil;
// start couroutine which returns control immediately
}
return self;
}
-(id)initAsCopyOf:(CSFilterHandle *)other
{
parent=nil; coro=nil; [self release];
[self _raiseNotImplemented:_cmd];
return nil;
}
-(void)dealloc
{
[parent release];
[coro release];
[super dealloc];
}
-(off_t)offsetInFile { return pos; }
-(int)readAtMost:(int)num toBuffer:(void *)buffer
{
if(!num) return 0;
ptr=buffer;
left=num;
if(!coro)
{
coro=[self newCoroutine];
[(id)coro filter];
} else [coro switchTo];
//if(eof)...
return num-left;
}
-(void)filter {}
@end
*/
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