cmd/tr/cmap.c

163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore/*
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * Copyright (c) 2004 Tim J. Robbins.
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * All rights reserved.
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore *
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * Redistribution and use in source and binary forms, with or without
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * modification, are permitted provided that the following conditions
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * are met:
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * 1. Redistributions of source code must retain the above copyright
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore *    notice, this list of conditions and the following disclaimer.
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * 2. Redistributions in binary form must reproduce the above copyright
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore *    notice, this list of conditions and the following disclaimer in the
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore *    documentation and/or other materials provided with the distribution.
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore *
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * SUCH DAMAGE.
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore */
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore/*
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * "Character map" ADT. Stores mappings between pairs of characters in a
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * splay tree, with a lookup table cache to simplify looking up the first
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * bunch of characters (which are presumably more common than others).
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore */
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore#include <assert.h>
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore#include <limits.h>
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore#include <stdbool.h>
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore#include <stdlib.h>
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore#include <wchar.h>
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore#include "cmap.h"
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amorestatic struct cmapnode *cmap_splay(struct cmapnode *, wint_t);
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore/*
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * cmap_alloc --
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore *  Allocate a character map.
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore */
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amorestruct cmap *
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amorecmap_alloc(void)
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore{
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    struct cmap *cm;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    cm = malloc(sizeof (*cm));
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    if (cm == NULL)
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        return (NULL);
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    cm->cm_root = NULL;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    cm->cm_def = CM_DEF_SELF;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    cm->cm_havecache = false;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    cm->cm_min = cm->cm_max = 0;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    return (cm);
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore}
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore/*
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * cmap_add --
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore *  Add a mapping from "from" to "to" to the map.
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore */
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amorebool
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amorecmap_add(struct cmap *cm, wint_t from, wint_t to)
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore{
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    struct cmapnode *cmn, *ncmn;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    cm->cm_havecache = false;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    if (cm->cm_root == NULL) {
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        cmn = malloc(sizeof (*cmn));
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        if (cmn == NULL)
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore            return (false);
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        cmn->cmn_from = from;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        cmn->cmn_to = to;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        cmn->cmn_left = cmn->cmn_right = NULL;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        cm->cm_root = cmn;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        cm->cm_min = cm->cm_max = from;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        return (true);
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    }
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    cmn = cm->cm_root = cmap_splay(cm->cm_root, from);
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    if (cmn->cmn_from == from) {
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        cmn->cmn_to = to;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        return (true);
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    }
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    ncmn = malloc(sizeof (*ncmn));
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    if (ncmn == NULL)
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        return (false);
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    ncmn->cmn_from = from;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    ncmn->cmn_to = to;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    if (from < cmn->cmn_from) {
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        ncmn->cmn_left = cmn->cmn_left;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        ncmn->cmn_right = cmn;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        cmn->cmn_left = NULL;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    } else {
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        ncmn->cmn_right = cmn->cmn_right;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        ncmn->cmn_left = cmn;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        cmn->cmn_right = NULL;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    }
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    if (from < cm->cm_min)
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        cm->cm_min = from;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    if (from > cm->cm_max)
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        cm->cm_max = from;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    cm->cm_root = ncmn;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    return (true);
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore}
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore/*
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * cmap_lookup_hard --
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore *  Look up the mapping for a character without using the cache.
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore */
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amorewint_t
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amorecmap_lookup_hard(struct cmap *cm, wint_t ch)
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore{
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    if (cm->cm_root != NULL) {
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        cm->cm_root = cmap_splay(cm->cm_root, ch);
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        if (cm->cm_root->cmn_from == ch)
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore            return (cm->cm_root->cmn_to);
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    }
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    return (cm->cm_def == CM_DEF_SELF ? ch : cm->cm_def);
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore}
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore/*
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * cmap_cache --
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore *  Update the cache.
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore */
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amorevoid
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amorecmap_cache(struct cmap *cm)
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore{
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    wint_t ch;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    for (ch = 0; ch < CM_CACHE_SIZE; ch++)
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        cm->cm_cache[ch] = cmap_lookup_hard(cm, ch);
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    cm->cm_havecache = true;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore}
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore/*
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore * cmap_default --
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore *  Change the value that characters without mappings map to, and
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore *  return the old value. The special character value CM_MAP_SELF
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore *  means characters map to themselves.
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore */
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amorewint_t
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amorecmap_default(struct cmap *cm, wint_t def)
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore{
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    wint_t old;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    old = cm->cm_def;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    cm->cm_def = def;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    cm->cm_havecache = false;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    return (old);
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore}
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amorestatic struct cmapnode *
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amorecmap_splay(struct cmapnode *t, wint_t ch)
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore{
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    struct cmapnode N, *l, *r, *y;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    /*
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore     * Based on public domain code from Sleator.
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore     */
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    assert(t != NULL);
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    N.cmn_left = N.cmn_right = NULL;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    l = r = &N;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    for (;;) {
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        if (ch < t->cmn_from) {
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore            if (t->cmn_left != NULL &&
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore                ch < t->cmn_left->cmn_from) {
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore                y = t->cmn_left;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore                t->cmn_left = y->cmn_right;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore                y->cmn_right = t;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore                t = y;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore            }
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore            if (t->cmn_left == NULL)
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore                break;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore            r->cmn_left = t;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore            r = t;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore            t = t->cmn_left;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        } else if (ch > t->cmn_from) {
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore            if (t->cmn_right != NULL &&
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore                ch > t->cmn_right->cmn_from) {
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore                y = t->cmn_right;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore                t->cmn_right = y->cmn_left;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore                y->cmn_left = t;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore                t = y;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore            }
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore            if (t->cmn_right == NULL)
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore                break;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore            l->cmn_right = t;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore            l = t;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore            t = t->cmn_right;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore        } else
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore            break;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    }
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    l->cmn_right = t->cmn_left;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    r->cmn_left = t->cmn_right;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    t->cmn_left = N.cmn_right;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    t->cmn_right = N.cmn_left;
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore    return (t);
163bd69b3c164dda2a59c7f08ca788e7d6ba9beaGarrett D'Amore}