Fix bug in deleteRelCatEntry(#1)

* Bug in deleteRelCatEntry
modified:   block_access.cpp

* - Typo in previous commit corrected to `relcat_rec[1]`
- The slot map update should be done after the getRecord to avoid error messages

block_access.cpp

@@ -936,19 +936,22 @@ int deleteRelCatEntry(recId relcat_recid, Attribute relcat_rec[6]) {
 	relcat_header.numEntries = relcat_header.numEntries - 1;
 	setHeader(&relcat_header, 4);
 	unsigned char relcat_slotmap[20];
-	getSlotmap(relcat_slotmap, 4);
-	relcat_slotmap[relcat_recid.slot] = SLOT_UNOCCUPIED;
-	setSlotmap(relcat_slotmap, 20, relcat_recid.block);
-
+
 	getRecord(relcat_rec, 4, 0);
 	relcat_rec[2].nval = relcat_rec[2].nval - 1;
 	setRecord(relcat_rec, 4, 0);
 
+	getRecord(relcat_rec, 4, relcat_recid.slot);
 	int no_of_attrs = relcat_rec[1].nval;
+
 	getRecord(relcat_rec, 4, 1);
 	relcat_rec[2].nval = relcat_rec[2].nval - no_of_attrs;
 	setRecord(relcat_rec, 4, 1);
 
+	getSlotmap(relcat_slotmap, 4);
+	relcat_slotmap[relcat_recid.slot] = SLOT_UNOCCUPIED;
+	setSlotmap(relcat_slotmap, 20, relcat_recid.block);
+
 	FILE *disk = fopen(&DISK_PATH[0], "rb+");
 	fseek(disk, (relcat_recid.block) * BLOCK_SIZE + HEADER_SIZE + SLOTMAP_SIZE_RELCAT_ATTRCAT +
 	            relcat_recid.slot * NO_OF_ATTRS_RELCAT_ATTRCAT * ATTR_SIZE, SEEK_SET);