Fix insertion into end of page which have right link. Previous coding

inserts all avaliable items although part of them should be inserted to
right page. Added check on right bound of page.

Author: feodor

rumbtree.c

@@ -203,10 +203,6 @@ rumFindLeafPage(RumBtree btree, RumBtreeStack * stack)
 
 /*
  * Step from current page.
- *
- * The next page is locked first, before releasing the current page. This is
- * crucial to protect from concurrent page deletion (see comment in
- * rumDeletePage).
  */
 Buffer
 rumStep(Buffer buffer, Relation index, int lockmode,
@@ -229,8 +225,8 @@ rumStep(Buffer buffer, Relation index, int lockmode,
 	}
 
 	nextbuffer = ReadBuffer(index, blkno);
-	LockBuffer(nextbuffer, lockmode);
 	UnlockReleaseBuffer(buffer);
+	LockBuffer(nextbuffer, lockmode);
 
 	/* Sanity check that the page we stepped to is of similar kind. */
 	page = BufferGetPage(nextbuffer);

rumdatapage.c

@@ -905,9 +905,18 @@ dataPlaceToPage(RumBtree btree, Page page, OffsetNumber off)
 				if (stopAppend)
 					 /* there is no free space on page */
 					break;
-				else
+				else if (RumPageRightMost(page))
 					/* force insertion of new item */
 					cmp = 1;
+				else if ((cmp = compareRumKey(btree->rumstate, btree->entryAttnum,
+											  RumDataPageGetRightBound(page),
+											  btree->items + btree->curitem)) >= 0)
+				{
+					/* force insertion of new item */
+				}
+				else
+					/* new items should be inserted on next page */
+					break;
 			}
 			else if (off <= maxoff)
 			{
@@ -930,10 +939,7 @@ dataPlaceToPage(RumBtree btree, Page page, OffsetNumber off)
 				copyItemEmpty = true;
 
 				if (cmp == 0)
-				{
 					btree->curitem++;
-					insertCount++;
-				}
 			}
 			else /* if (cmp > 0) */
 			{
@@ -957,8 +963,8 @@ dataPlaceToPage(RumBtree btree, Page page, OffsetNumber off)
 
 					Assert(ptr - oldptr == newItemSize);
 					iptr = btree->items[btree->curitem].iptr;
-					btree->curitem++;
 					freespace -= newItemSize;
+					btree->curitem++;
 					insertCount++;
 				}
 				else
@@ -970,7 +976,6 @@ dataPlaceToPage(RumBtree btree, Page page, OffsetNumber off)
 			Assert(RumDataPageFreeSpacePre(page, ptr) >= 0);
 		}
 
-		Assert(insertCount > 0);
 		RumPageGetOpaque(page)->maxoff += insertCount;
 
 		/* Update indexes in the end of page */
@@ -1209,7 +1214,6 @@ dataSplitPageInternal(RumBtree btree, Buffer lbuf, Buffer rbuf,
 	OffsetNumber maxoff = RumPageGetOpaque(newlPage)->maxoff;
 	Size		pageSize = PageGetPageSize(newlPage);
 	Size		freeSpace;
-	uint32		nCopied = 1;
 
 	static char vector[2 * BLCKSZ];
 
@@ -1220,36 +1224,13 @@ dataSplitPageInternal(RumBtree btree, Buffer lbuf, Buffer rbuf,
 	memcpy(vector, RumDataPageGetItem(newlPage, FirstOffsetNumber),
 		   maxoff * sizeofitem);
 
-	if (RumPageIsLeaf(newlPage) && RumPageRightMost(newlPage) &&
-		off > RumPageGetOpaque(newlPage)->maxoff)
-	{
-		nCopied = 0;
-		while (btree->curitem < btree->nitem &&
-			   maxoff * sizeof(ItemPointerData) < 2 * (freeSpace - sizeof(ItemPointerData)))
-		{
-			memcpy(vector + maxoff * sizeof(ItemPointerData),
-				   &btree->items[btree->curitem].iptr,
-				   sizeof(ItemPointerData));
-			maxoff++;
-			nCopied++;
-			btree->curitem++;
-		}
-	}
-	else
-	{
-		ptr = vector + (off - 1) * sizeofitem;
-		if (maxoff + 1 - off != 0)
-			memmove(ptr + sizeofitem, ptr, (maxoff - off + 1) * sizeofitem);
-		if (RumPageIsLeaf(newlPage))
-		{
-			memcpy(ptr, &btree->items[btree->curitem].iptr, sizeofitem);
-			btree->curitem++;
-		}
-		else
-			memcpy(ptr, &(btree->pitem), sizeofitem);
+	Assert(!RumPageIsLeaf(newlPage));
+	ptr = vector + (off - 1) * sizeofitem;
+	if (maxoff + 1 - off != 0)
+		memmove(ptr + sizeofitem, ptr, (maxoff - off + 1) * sizeofitem);
+	memcpy(ptr, &(btree->pitem), sizeofitem);
 
-		maxoff++;
-	}
+	maxoff++;
 
 	/*
 	 * we suppose that during index creation table scaned from begin to end,