list.h

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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 General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 *
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/** ------------------------------------------------------------------------
        This file contains routines for manipulating generic lists.
        Lists are implemented with a "harness".  In other words, each
        node in the list consists of two pointers, one to the data item
        and one to the next node in the list.  The head of the list is
        the same struct as each node, but the "item" ptr is used to point
        to the current member of the list (used by the first_in_list and
        next_in_list functions).

 This file is available under and governed by the GNU General Public
 License version 2 only, as published by the Free Software Foundation.
 However, the following notice accompanied the original version of this
 file:

Copyright 1994 Hewlett-Packard Co.
Copyright 1996, 1998  The Open Group

Permission to use, copy, modify, distribute, and sell this software and its
documentation for any purpose is hereby granted without fee, provided that
the above copyright notice appear in all copies and that both that
copyright notice and this permission notice appear in supporting
documentation.

The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.

Except as contained in this notice, the name of The Open Group shall
not be used in advertising or otherwise to promote the sale, use or
other dealings in this Software without prior written authorization
from The Open Group.

    -------------------------------------------------------------------- **/

#ifndef LIST_DEF
#define LIST_DEF

#include <X11/Xfuncproto.h>
#define LESS    -1
#define EQUAL   0
#define GREATER 1
#define DUP_WHOLE_LIST  0
#define START_AT_CURR   1

typedef struct _list_item {
    struct _list_item *next;
    union {
        void *item;              /* in normal list node, pts to data */
        struct _list_item *curr; /* in list head, pts to curr for 1st, next */
    } ptr;
} list, list_item, *list_ptr;

typedef void (*DESTRUCT_FUNC_PTR)(
void *
);

void zero_list(
          list_ptr
    );
int add_to_list (
          list_ptr , void *
    );
list_ptr new_list (
          void
    );
list_ptr dup_list_head (
          list_ptr , int
    );
unsigned int list_length(
          list_ptr
    );
void *delete_from_list (
          list_ptr , void *
    );
void delete_list(
          list_ptr , int
    );
void delete_list_destroying (
          list_ptr , DESTRUCT_FUNC_PTR
    );
void *first_in_list (
          list_ptr
    );
void *next_in_list (
          list_ptr
    );
int list_is_empty (
          list_ptr
    );

#endif