1 /*
2  * bltChain.h --
3  *
4  * Copyright 1993-2000 Lucent Technologies, Inc.
5  *
6  * Permission to use, copy, modify, and distribute this software and
7  * its documentation for any purpose and without fee is hereby
8  * granted, provided that the above copyright notice appear in all
9  * copies and that both that the copyright notice and warranty
10  * disclaimer appear in supporting documentation, and that the names
11  * of Lucent Technologies any of their entities not be used in
12  * advertising or publicity pertaining to distribution of the software
13  * without specific, written prior permission.
14  *
15  * Lucent Technologies disclaims all warranties with regard to this
16  * software, including all implied warranties of merchantability and
17  * fitness.  In no event shall Lucent Technologies be liable for any
18  * special, indirect or consequential damages or any damages
19  * whatsoever resulting from loss of use, data or profits, whether in
20  * an action of contract, negligence or other tortuous action, arising
21  * out of or in connection with the use or performance of this
22  * software.
23  */
24 #ifndef _BLT_CHAIN_H
25 #define _BLT_CHAIN_H
26 
27 typedef struct Blt_ChainLinkStruct Blt_ChainLink;
28 
29 /*
30  * A Blt_ChainLink is the container structure for the Blt_Chain.
31  */
32 
33 struct Blt_ChainLinkStruct {
34     Blt_ChainLink *prevPtr;	/* Link to the previous link */
35     Blt_ChainLink *nextPtr;	/* Link to the next link */
36     ClientData clientData;	/* Pointer to the data object */
37 };
38 
39 typedef int (Blt_ChainCompareProc) _ANSI_ARGS_((Blt_ChainLink **l1PtrPtr,
40 	Blt_ChainLink **l2PtrPtr));
41 
42 /*
43  * A Blt_Chain is a doubly chained list structure.
44  */
45 typedef struct {
46     Blt_ChainLink *headPtr;	/* Pointer to first element in chain */
47     Blt_ChainLink *tailPtr;	/* Pointer to last element in chain */
48     int nLinks;			/* Number of elements in chain */
49 } Blt_Chain;
50 
51 extern void Blt_ChainInit _ANSI_ARGS_((Blt_Chain * chainPtr));
52 extern Blt_Chain *Blt_ChainCreate _ANSI_ARGS_(());
53 extern void Blt_ChainDestroy _ANSI_ARGS_((Blt_Chain * chainPtr));
54 extern Blt_ChainLink *Blt_ChainNewLink _ANSI_ARGS_((void));
55 extern Blt_ChainLink *Blt_ChainAllocLink _ANSI_ARGS_((unsigned int size));
56 extern Blt_ChainLink *Blt_ChainAppend _ANSI_ARGS_((Blt_Chain * chainPtr,
57 	ClientData clientData));
58 extern Blt_ChainLink *Blt_ChainPrepend _ANSI_ARGS_((Blt_Chain * chainPtr,
59 	ClientData clientData));
60 extern void Blt_ChainReset _ANSI_ARGS_((Blt_Chain * chainPtr));
61 extern void Blt_ChainLinkAfter _ANSI_ARGS_((Blt_Chain * chainPtr,
62 	Blt_ChainLink * linkPtr, Blt_ChainLink * afterLinkPtr));
63 extern void Blt_ChainLinkBefore _ANSI_ARGS_((Blt_Chain * chainPtr,
64 	Blt_ChainLink * linkPtr, Blt_ChainLink * beforeLinkPtr));
65 extern void Blt_ChainUnlinkLink _ANSI_ARGS_((Blt_Chain * chainPtr,
66 	Blt_ChainLink * linkPtr));
67 extern void Blt_ChainDeleteLink _ANSI_ARGS_((Blt_Chain * chainPtr,
68 	Blt_ChainLink * linkPtr));
69 extern Blt_ChainLink *Blt_ChainGetNthLink _ANSI_ARGS_((Blt_Chain * chainPtr, int n));
70 extern void Blt_ChainSort _ANSI_ARGS_((Blt_Chain * chainPtr,
71 	Blt_ChainCompareProc * proc));
72 
73 #define Blt_ChainGetLength(c)	(((c) == NULL) ? 0 : (c)->nLinks)
74 #define Blt_ChainFirstLink(c)	(((c) == NULL) ? NULL : (c)->headPtr)
75 #define Blt_ChainLastLink(c)	(((c) == NULL) ? NULL : (c)->tailPtr)
76 #define Blt_ChainPrevLink(l)	((l)->prevPtr)
77 #define Blt_ChainNextLink(l) 	((l)->nextPtr)
78 #define Blt_ChainGetValue(l)  	((l)->clientData)
79 #define Blt_ChainSetValue(l, value) ((l)->clientData = (ClientData)(value))
80 #define Blt_ChainAppendLink(c, l) \
81 	(Blt_ChainLinkBefore((c), (l), (Blt_ChainLink *)NULL))
82 #define Blt_ChainPrependLink(c, l) \
83 	(Blt_ChainLinkAfter((c), (l), (Blt_ChainLink *)NULL))
84 
85 #endif /* _BLT_CHAIN_H */
86