/* Copyright (C) 1992-2017 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ #include <stddef.h> #include <search.h> /* Insert ELEM into a doubly-linked list, after PREV. */ void insque (void *elem, void *prev) { if (prev == NULL) { ((struct qelem *) elem)->q_forw = NULL; ((struct qelem *) elem)->q_back = NULL; } else { struct qelem *next = ((struct qelem *) prev)->q_forw; ((struct qelem *) prev)->q_forw = (struct qelem *) elem; if (next != NULL) next->q_back = (struct qelem *) elem; ((struct qelem *) elem)->q_forw = next; ((struct qelem *) elem)->q_back = (struct qelem *) prev; } } /* Unlink ELEM from the doubly-linked list that it is in. */ void remque (void *elem) { struct qelem *next = ((struct qelem *) elem)->q_forw; struct qelem *prev = ((struct qelem *) elem)->q_back; if (next != NULL) next->q_back = prev; if (prev != NULL) prev->q_forw = (struct qelem *) next; }