projects / unix-history / blame
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|---|---|---|
| 15637ed4 RG |
1 | /* |
| 2 | * Copyright (c) 1988, 1989, 1990 The Regents of the University of California. | |
| 3 | * All rights reserved. | |
| 4 | * | |
| 5 | * This code is derived from software contributed to Berkeley by | |
| 6 | * Adam de Boor. | |
| 7 | * | |
| 8 | * Redistribution and use in source and binary forms, with or without | |
| 9 | * modification, are permitted provided that the following conditions | |
| 10 | * are met: | |
| 11 | * 1. Redistributions of source code must retain the above copyright | |
| 12 | * notice, this list of conditions and the following disclaimer. | |
| 13 | * 2. Redistributions in binary form must reproduce the above copyright | |
| 14 | * notice, this list of conditions and the following disclaimer in the | |
| 15 | * documentation and/or other materials provided with the distribution. | |
| 16 | * 3. All advertising materials mentioning features or use of this software | |
| 17 | * must display the following acknowledgement: | |
| 18 | * This product includes software developed by the University of | |
| 19 | * California, Berkeley and its contributors. | |
| 20 | * 4. Neither the name of the University nor the names of its contributors | |
| 21 | * may be used to endorse or promote products derived from this software | |
| 22 | * without specific prior written permission. | |
| 23 | * | |
| 24 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND | |
| 25 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
| 26 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
| 27 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE | |
| 28 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
| 29 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
| 30 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
| 31 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |
| 32 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |
| 33 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
| 34 | * SUCH DAMAGE. | |
| 35 | * | |
| 36 | * @(#)lstInt.h 5.4 (Berkeley) 12/28/90 | |
| 37 | */ | |
| 38 | ||
| 39 | /*- | |
| 40 | * lstInt.h -- | |
| 41 | * Internals for the list library | |
| 42 | */ | |
| 43 | #ifndef _LSTINT_H_ | |
| 44 | #define _LSTINT_H_ | |
| 45 | ||
| 46 | #include "lst.h" | |
| 47 | ||
| 48 | typedef struct ListNode { | |
| 49 | struct ListNode *prevPtr; /* previous element in list */ | |
| 50 | struct ListNode *nextPtr; /* next in list */ | |
| 51 | short useCount:8, /* Count of functions using the node. | |
| 52 | * node may not be deleted until count | |
| 53 | * goes to 0 */ | |
| 54 | flags:8; /* Node status flags */ | |
| 55 | ClientData datum; /* datum associated with this element */ | |
| 56 | } *ListNode; | |
| 57 | /* | |
| 58 | * Flags required for synchronization | |
| 59 | */ | |
| 60 | #define LN_DELETED 0x0001 /* List node should be removed when done */ | |
| 61 | ||
| 62 | #define NilListNode ((ListNode)-1) | |
| 63 | ||
| 64 | typedef enum { | |
| 65 | Head, Middle, Tail, Unknown | |
| 66 | } Where; | |
| 67 | ||
| 68 | typedef struct { | |
| 69 | ListNode firstPtr; /* first node in list */ | |
| 70 | ListNode lastPtr; /* last node in list */ | |
| 71 | Boolean isCirc; /* true if the list should be considered | |
| 72 | * circular */ | |
| 73 | /* | |
| 74 | * fields for sequential access | |
| 75 | */ | |
| 76 | Where atEnd; /* Where in the list the last access was */ | |
| 77 | Boolean isOpen; /* true if list has been Lst_Open'ed */ | |
| 78 | ListNode curPtr; /* current node, if open. NilListNode if | |
| 79 | * *just* opened */ | |
| 80 | ListNode prevPtr; /* Previous node, if open. Used by | |
| 81 | * Lst_Remove */ | |
| 82 | } *List; | |
| 83 | ||
| 84 | #define NilList ((List)-1) | |
| 85 | ||
| 86 | /* | |
| 87 | * PAlloc (var, ptype) -- | |
| 88 | * Allocate a pointer-typedef structure 'ptype' into the variable 'var' | |
| 89 | */ | |
| 90 | #define PAlloc(var,ptype) var = (ptype) malloc (sizeof (*var)) | |
| 91 | ||
| 92 | /* | |
| 93 | * LstValid (l) -- | |
| 94 | * Return TRUE if the list l is valid | |
| 95 | */ | |
| 96 | #define LstValid(l) (((Lst)l == NILLST) ? FALSE : TRUE) | |
| 97 | ||
| 98 | /* | |
| 99 | * LstNodeValid (ln, l) -- | |
| 100 | * Return TRUE if the LstNode ln is valid with respect to l | |
| 101 | */ | |
| 102 | #define LstNodeValid(ln, l) ((((LstNode)ln) == NILLNODE) ? FALSE : TRUE) | |
| 103 | ||
| 104 | /* | |
| 105 | * LstIsEmpty (l) -- | |
| 106 | * TRUE if the list l is empty. | |
| 107 | */ | |
| 108 | #define LstIsEmpty(l) (((List)l)->firstPtr == NilListNode) | |
| 109 | ||
| 110 | #endif _LSTINT_H_ |