BSD 3 development

[unix-history] / usr / src / cmd / struct / 0.list.c

#include <stdio.h>
#include "def.h"

struct list *consls(v,ls)               /* make list */
VERT v;
struct list *ls;
       {
       struct list *temp;
       temp = challoc(sizeof(*temp));
       temp->elt = v;
       temp->nxtlist = ls;
       return(temp);
       }

struct list *append(v,ls)               /* return ls . v */
VERT v;
struct list *ls;
       {
       struct list *temp;
       if (!ls) return(consls(v,0));
       for (temp = ls; temp -> nxtlist; temp = temp->nxtlist)
               ;
       temp->nxtlist = consls(v,0);
       return(ls);
       }


freelst(ls)
struct list *ls;
       {
       if (!ls) return;
       if (ls->nxtlist)
               freelst(ls->nxtlist);
       chfree(ls,sizeof(*ls));
       }


oneelt(ls)              /* return w if w is only elt of ls, UNDEFINED otherwise */
struct list *ls;
       {
       if (!ls) return(UNDEFINED);
       if (ls->nxtlist) return(UNDEFINED);
       return(ls->elt);
       }


lslen(ls)               /* return number of elements in list ls */
struct list *ls;
       {
       int count;
       struct list *lp;
       count = 0;
       for (lp = ls; lp; lp = lp->nxtlist)
               ++count;
       return(count);
       }


prlst(ls)
struct list *ls;
       {
       struct list *lp;
       for (lp = ls; lp; lp = lp->nxtlist)
               printf("%d,",lp->elt);
       fprintf(stderr,"\n");
       }