Import patches mistakenly applied to OPENLDAP_DEVEL_REFERRALS.

ldap_modify: delete of last attribute value should delete attribute (ITS#229)
thr_nt: use sleep to yield

libraries/libldap_r/thr_nt.c

@@ -65,6 +65,7 @@ ldap_pvt_thread_kill( ldap_pvt_thread_t thread, int signo )
 int 
 ldap_pvt_thread_yield( void )
 {
+	Sleep( 0 );
 	return 0;
 }
 

servers/slapd/back-bdb2/modify.c

@@ -355,6 +355,17 @@ bdb2i_delete_values(
 				a->a_vals[k - 1] = a->a_vals[k];
 			}
 			a->a_vals[k - 1] = NULL;
+
+			/* delete the entire attribute, if no values remain */
+			if ( a->a_vals[0] == NULL) {
+				Debug( LDAP_DEBUG_ARGS,
+					"removing entire attribute %s\n",
+					mod->mod_type, 0, 0 );
+				if ( attr_delete( &e->e_attrs, mod->mod_type ) ) {
+					return LDAP_NO_SUCH_ATTRIBUTE;
+				}
+			}
+
 			break;
 		}
 

servers/slapd/back-ldbm/modify.c

@@ -367,6 +367,17 @@ delete_values(
 				a->a_vals[k - 1] = a->a_vals[k];
 			}
 			a->a_vals[k - 1] = NULL;
+
+			/* delete the entire attribute, if no values remain */
+			if ( a->a_vals[0] == NULL) {
+				Debug( LDAP_DEBUG_ARGS,
+					"removing entire attribute %s\n",
+					mod->mod_type, 0, 0 );
+				if ( attr_delete( &e->e_attrs, mod->mod_type ) ) {
+					return LDAP_NO_SUCH_ATTRIBUTE;
+				}
+			}
+
 			break;
 		}