chiark - git - mdw - mup/blame - mup/mup/mainlist.c

Commit	Line	Data
69695f33 MW	1
	2	/* Copyright (c) 1995, 2001, 2003 by Arkkra Enterprises */
	3	/* All rights reserved */
	4
	5	/* functions for manipulating the main list of structs, allocating,
	6	* inserting and deleting. */
	7
	8	#include "defines.h"
	9	#include "structs.h"
	10	#include "globals.h"
	11
	12
	13
	14
	15	/* allocate a new MAINLL struct and return a pointer to it */
	16
	17	struct MAINLL *
	18	newMAINLLstruct(structtype, lineno)
	19
	20	int structtype; /* what kind to allocate: S_SSV, S_BAR, etc */
	21	int lineno; /* input line number that caused this call */
	22
	23	{
	24	struct MAINLL new_p; / the newly allocated struct */
	25
	26
	27	debug(4, "newMAINLLstruct lineno=%d structtype=%d", lineno, structtype);
	28
	29	/* allocate the struct */
	30	CALLOC(MAINLL, new_p, 1);
	31
	32	/* fill in the type to say which union member will be used */
	33	new_p->str = (short) structtype;
	34
	35	/* initialize link pointers to point nowhere */
	36	new_p->next = new_p->prev = (struct MAINLL *) 0;
	37
	38
	39	/* now allocate and initialize the proper S_* struct */
	40	switch (structtype) {
	41
	42	case S_SSV:
	43	CALLOC(SSV, new_p->u.ssv_p, 1);
	44	break;
	45
	46	case S_STAFF:
	47	CALLOC(STAFF, new_p->u.staff_p, 1);
	48	break;
	49
	50	case S_BAR:
	51	CALLOC(BAR, new_p->u.bar_p, 1);
	52	break;
	53
	54	case S_LINE:
	55	CALLOC(LINE, new_p->u.line_p, 1);
	56	break;
	57
	58	case S_CURVE:
	59	CALLOC(CURVE, new_p->u.curve_p, 1);
	60	break;
	61
	62	case S_PRHEAD:
	63	CALLOC(PRHEAD, new_p->u.prhead_p, 1);
	64	break;
65
66	case S_CHHEAD:
67	CALLOC(CHHEAD, new_p->u.chhead_p, 1);
68	break;
69
70	case S_FEED:
71	CALLOC(FEED, new_p->u.feed_p, 1);
72	/* negative value for margin means use score parameter */
73	new_p->u.feed_p->rightmargin = -1.0;
74	new_p->u.feed_p->leftmargin = -1.0;
75	break;
76
77	case S_BLOCKHEAD:
78	CALLOC(BLOCKHEAD, new_p->u.blockhead_p, 1);
79	break;
80
81	case S_CLEFSIG:
82	CALLOC(CLEFSIG, new_p->u.clefsig_p, 1);
83	break;
84
85	default:
86	pfatal("unknown structure type %d requested", structtype);
87	break;
88	}
89
90	/* remember the user's input file and line number,
91	* so in case we have to print an error message later,
92	* we know which line number to print */
93	new_p->inputlineno = (short) lineno;
94	new_p->inputfile = Curr_filename;
95
96	/* return the newly allocated struct */
97	return(new_p);
98	}
99	\f
100
101	/* insert MAINLL struct into main list, after an arbitrary existing struct. */
102	/* If where to insert is NULL, put at beginning of list */
103
104	void
105	insertMAINLL(info_p, where)
106
107	struct MAINLL info_p; / what to insert */
108	struct MAINLL where; / put it right after this one in the list */
109
110	{
111	if (info_p == where) {
112	/* Any bug that gets us here would cause an infinite loop */
113	pfatal("attempt to insert a MAINLL after itself");
114	}
115
116	/* if where is NULL, this means to insert at beginning of list */
117	if (where == (struct MAINLL *) 0) {
118	if (Mainllhc_p != (struct MAINLL *) 0) {
119	Mainllhc_p->prev = info_p;
120	}
121	info_p->prev = (struct MAINLL *) 0;
122	info_p->next = Mainllhc_p;
123	Mainllhc_p = info_p;
124	}
125
126	else {
127	/* standard linked list stuff --
128	* fix up the next and prev pointers */
129	info_p->next = where->next;
130	info_p->prev = where;
131	if (where->next != (struct MAINLL *) 0) {
132	where->next->prev = info_p;
133	}
134	where->next = info_p;
135	}
136
137	/* if we just added to the very end of the list, need to adjust the
138	* tail pointer */
139	if ( (Mainlltc_p == (struct MAINLL *) 0) \|\| (where == Mainlltc_p) ) {
140	Mainlltc_p = info_p;
141	}
142	}
143	\f
144
145	/* unlink a MAINLL struct from the main list
146	* (probably for re-inserting elsewhere). The struct is not freed. */
147
148	void
149	unlinkMAINLL(which_p)
150
151	struct MAINLL which_p; / the one to unlink */
152
153	{
154	if (which_p->prev != (struct MAINLL *) 0) {
155	which_p->prev->next = which_p->next;
156	}
157	if (which_p->next != (struct MAINLL *) 0) {
158	which_p->next->prev = which_p->prev;
159	}
160
161	/* if this happened to be the tail cell, need to fix up */
162	if (Mainlltc_p == which_p) {
163	Mainlltc_p = which_p->prev;
164	}
165
166	/* likewise for head cell */
167	if (Mainllhc_p == which_p) {
168	Mainllhc_p = which_p->next;
169	}
170	}