Initial import of the CDE 2.1.30 sources from the Open Group.

cde/lib/tt/mini_isam/isdel1key.c

@@ -0,0 +1,78 @@
+/*%%  (c) Copyright 1993, 1994 Hewlett-Packard Company			 */
+/*%%  (c) Copyright 1993, 1994 International Business Machines Corp.	 */
+/*%%  (c) Copyright 1993, 1994 Sun Microsystems, Inc.			 */
+/*%%  (c) Copyright 1993, 1994 Novell, Inc. 				 */
+/*%%  $XConsortium: isdel1key.c /main/3 1995/10/23 11:37:24 rswiston $ 			 				 */
+#ifndef lint
+static char sccsid[] = "@(#)isdel1key.c 1.3 89/07/17 Copyr 1988 Sun Micro";
+#endif
+/*
+ * Copyright (c) 1988 by Sun Microsystems, Inc.
+ */
+
+/*
+ * isdel1key.c
+ *
+ * Description: 
+ *	Delete a key entry from index
+ *	
+ *
+ */
+
+#include "isam_impl.h"
+
+void
+_del1key(fcb, pkeydesc2, record, recnum)
+    Fcb			*fcb;	
+    Keydesc2		*pkeydesc2;
+    char		*record;
+    Recno		recnum;
+{
+    char		keybuf[MAXKEYSIZE];
+    Btree		*btree;
+    char		*pkey;
+
+    /*
+     * Special case when there is no primary key.
+     */
+    if (pkeydesc2->k2_nparts == 0)
+	return;
+
+    memset((char *)keybuf, 0,pkeydesc2->k2_len);
+    _iskey_extract(pkeydesc2,record,keybuf);
+    strecno(recnum, keybuf);
+
+    btree = _isbtree_create(fcb, pkeydesc2);
+    _isbtree_search(btree, keybuf);
+
+    if (ALLOWS_DUPS2(pkeydesc2)) {
+
+	/*
+	 * We must now scan all the duplicates till we found one with
+	 * matching recno. We are positioned just before the first duplicate.
+	 * Remember that the duplicates are ordered by their serial number.
+	 *
+	 * If too many duplicate entries exists, the performance will be
+	 * poor.
+	 */
+	while ((pkey = _isbtree_next(btree)) != NULL) {
+	    if (ldrecno(pkey + KEY_RECNO_OFF) == recnum)
+		break;			     /* We found the entry */
+	}
+
+	if (pkey == NULL) 
+	    _isfatal_error("_del1key() cannot find entry in B tree");
+
+	_isbtree_remove(btree);
+    }
+    else {
+
+	if ((pkey = _isbtree_current(btree)) == NULL ||
+	    ldrecno(pkey + KEY_RECNO_OFF) != recnum)
+	    _isfatal_error("_del1key() cannot find entry in B tree");
+
+	_isbtree_remove(btree);
+    }
+
+    _isbtree_destroy(btree);
+}