*** src/backend/storage/large_object/inv_api.c.orig	Wed Apr 12 13:15:37 2000
--- src/backend/storage/large_object/inv_api.c	Thu Jun 15 02:10:27 2000
***************
*** 185,190 ****
--- 185,191 ----
  	retval->idesc = RelationGetDescr(indr);
  	retval->offset = retval->lowbyte = retval->highbyte = 0;
  	ItemPointerSetInvalid(&(retval->htid));
+ 	retval->flags = 0;
  
  	if (flags & INV_WRITE)
  	{
***************
*** 233,238 ****
--- 234,240 ----
  	retval->idesc = RelationGetDescr(indrel);
  	retval->offset = retval->lowbyte = retval->highbyte = 0;
  	ItemPointerSetInvalid(&(retval->htid));
+ 	retval->flags = 0;
  
  	if (flags & INV_WRITE)
  	{
***************
*** 371,384 ****
  	if (whence == SEEK_CUR)
  	{
  		offset += obj_desc->offset;		/* calculate absolute position */
- 		return inv_seek(obj_desc, offset, SEEK_SET);
  	}
! 
! 	/*
! 	 * if you seek past the end (offset > 0) I have no clue what happens
! 	 * :-(				  B.L.	 9/1/93
! 	 */
! 	if (whence == SEEK_END)
  	{
  		/* need read lock for getsize */
  		if (!(obj_desc->flags & IFS_RDLOCK))
--- 373,380 ----
  	if (whence == SEEK_CUR)
  	{
  		offset += obj_desc->offset;		/* calculate absolute position */
  	}
! 	else if (whence == SEEK_END)
  	{
  		/* need read lock for getsize */
  		if (!(obj_desc->flags & IFS_RDLOCK))
***************
*** 389,396 ****
  		offset += _inv_getsize(obj_desc->heap_r,
  							   obj_desc->hdesc,
  							   obj_desc->index_r);
- 		return inv_seek(obj_desc, offset, SEEK_SET);
  	}
  
  	/*
  	 * Whenever we do a seek, we turn off the EOF flag bit to force
--- 385,392 ----
  		offset += _inv_getsize(obj_desc->heap_r,
  							   obj_desc->hdesc,
  							   obj_desc->index_r);
  	}
+ 	/* now we can assume that the operation is SEEK_SET */
  
  	/*
  	 * Whenever we do a seek, we turn off the EOF flag bit to force
***************
*** 414,422 ****
  	 * stores the offset of the last byte that appears on it, and we have
  	 * an index on this.
  	 */
- 
- 
- 	/* right now, just assume that the operation is SEEK_SET */
  	if (obj_desc->iscan != (IndexScanDesc) NULL)
  	{
  		d = Int32GetDatum(offset);
--- 410,415 ----
***************
*** 424,430 ****
  	}
  	else
  	{
- 
  		ScanKeyEntryInitialize(&skey, 0x0, 1, F_INT4GE,
  							   Int32GetDatum(offset));
  
--- 417,422 ----
***************
*** 487,495 ****
  
  		/* copy the data from this block into the buffer */
  		d = heap_getattr(&tuple, 2, obj_desc->hdesc, &isNull);
  		ReleaseBuffer(buffer);
  
! 		fsblock = (struct varlena *) DatumGetPointer(d);
  
  		off = obj_desc->offset - obj_desc->lowbyte;
  		ncopy = obj_desc->highbyte - obj_desc->offset + 1;
--- 479,505 ----
  
  		/* copy the data from this block into the buffer */
  		d = heap_getattr(&tuple, 2, obj_desc->hdesc, &isNull);
+ 		fsblock = (struct varlena *) DatumGetPointer(d);
  		ReleaseBuffer(buffer);
  
! 		/*
! 		 * If block starts beyond current seek point, then we are looking
! 		 * at a "hole" (unwritten area) in the object.  Return zeroes for
! 		 * the "hole".
! 		 */
! 		if (obj_desc->offset < obj_desc->lowbyte)
! 		{
! 			int		nzeroes = obj_desc->lowbyte - obj_desc->offset;
! 
! 			if (nzeroes > (nbytes - nread))
! 				nzeroes = (nbytes - nread);
! 			MemSet(buf, 0, nzeroes);
! 			buf += nzeroes;
! 			nread += nzeroes;
! 			obj_desc->offset += nzeroes;
! 			if (nread >= nbytes)
! 				break;
! 		}
  
  		off = obj_desc->offset - obj_desc->lowbyte;
  		ncopy = obj_desc->highbyte - obj_desc->offset + 1;
***************
*** 535,548 ****
  		Buffer		buffer;
  
  		/*
! 		 * Fetch the current inversion file system block.  If the class
! 		 * storing the inversion file is empty, we don't want to do an
! 		 * index lookup, since index lookups choke on empty files (should
! 		 * be fixed someday).
  		 */
  
! 		if ((obj_desc->flags & IFS_ATEOF)
! 			|| obj_desc->heap_r->rd_nblocks == 0)
  			tuple.t_data = NULL;
  		else
  			inv_fetchtup(obj_desc, &tuple, &buffer);
--- 545,555 ----
  		Buffer		buffer;
  
  		/*
! 		 * Fetch the current inversion file system block.  We can skip
! 		 * the work if we already know we are at EOF.
  		 */
  
! 		if (obj_desc->flags & IFS_ATEOF)
  			tuple.t_data = NULL;
  		else
  			inv_fetchtup(obj_desc, &tuple, &buffer);