mdw@git.distorted.org.uk Git - mup/blob - mup/mup/mainlist.c

   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 }