BSD 3 development

[unix-history] / usr / src / cmd / apl / lex.c

#define lv yylval
#define v yyval


yylex()
{
       register c;
       register struct tab *tp;
       extern TERMtype;

       if(nlexsym != -1) {
               if (TERMtype == 1) dofix();             /* convert iline */
               c = nlexsym;
               nlexsym = -1;
               return(c);

       }
       while(litflag > 0) {
               if (TERMtype == 0)c = (int)*iline++;
               else c = asciich();
               if(c == '\n') {
                       nlexsym = 0;
                       return(eol);
               }
       }
       do
               if (TERMtype == 0)c = (int)*iline++;
               else c = asciich();
       while(c == ' ');
       if(c == '\n') {
               nlexsym = 0;
               return(eol);
       }
       if(alpha(c))
               return(getnam(c));
       if(digit(c) || c == '@' ||
           (c=='.' && digit(*iline)))
               return(getnum(c));
       c &= 0377;
       for(tp = tab; tp->input; tp++)
               if(tp->input == c) {
                       lv = tp->lexval;
                       return(tp->retval);
               }
       return(unk);
}

getnam(ic)
{
       char name[NAMS];
       register c;
       register char *cp;
       register struct nlist *np;

       cp = name;
       do {
               *cp++ = c;
               if (TERMtype == 0)c = (int)*iline++;
               else c = asciich();
       } while(alpha(c) || digit(c));
       *cp++ = 0;
       iline--;
       if(litflag < 0) {       /* commands */
               litflag = 0;
               for(c=0; comtab[c]; c+=3)
                       if(equal(name, comtab[c]))
                               break;
               lv = comtab[c+2];
               return(comtab[c+1]);
       }
       if(a_label(name)){
               return(numb);
       }
       for(np=nlist; np->namep; np++)
       if(equal(np->namep, name)) {
               lv = np;
               switch(np->use) {

               case NF:
                       return(nfun);

               case MF:
                       return(mfun);

               case DF:
                       return(dfun);
               }
               return(nam);
       }
       np->namep = alloc(cp-name);
       copy(CH, name, np->namep, cp-name);
       np->type = LV;
       lv = np;
       return(nam);
}

a_label(x)
register char *x;
{
register struct lablist *lblthru;

       lblthru = labldefs.nextll;
       while(lblthru) {
               if(equal(lblthru->lname,x)) {
                       datum = (double) lblthru->lno;
                       return(1);
               }
               lblthru = lblthru->nextll;
       }
       return(0);
}

getnum(ic)
{
       double d1, d2;
       register c, n, n1;
       int s, s1;

       s = 0;
       n = 0;
       d1 = 0.;
       c = ic;
       if(c == '@') {
               s++;
               if (TERMtype == 0)c = (int)*iline++;
               else c = asciich();
       }
       while(digit(c)) {
               d1 = d1*10. + c - '0';
               if (TERMtype == 0)c = (int)*iline++;
               else c = asciich();
       }
       if(c == '.') {
               if (TERMtype == 0)c = (int)*iline++;
               else c = asciich();
               while(digit(c)) {
                       d1 = d1*10. + c - '0';
                       if (TERMtype == 0)c = (int)*iline++;
                       else c = asciich();
                       n--;
               }
       }
       if(c == 'e') {
               s1 = 0;
               n1 = 0;
               if (TERMtype == 0)c = (int)*iline++;
               else c = asciich();
               if(c == '@') {
                       s1++;
                       if (TERMtype == 0)c = (int)*iline++;
                       else c = asciich();
               }
               while(digit(c)) {
                       n1 = n1*10 + c - '0';
                       if (TERMtype == 0)c = (int)*iline++;
                       else c = asciich();
               }
               if(s1)
                       n -= n1; else
                       n += n1;
       }
       n1 = n;
       if(n1 < 0)
               n1 = -n1;
       d2 = 1.;
       while(n1--)
               d2 *= 10.;
       if(n < 0)
               d1 /= d2; else
               d1 *= d2;
       if(s)
               d1 = -d1;
       iline--;
       datum = d1;
       return(numb);
}

alpha(s)
{
       register c;

       c = s & 0377;
       if(c >= 'a' && c <= 'z')
               return(1);
       if(c == 'H')
               return(1);
       if(c == 'F')
               return(1);
       if(c >= 0220 && c<=0252)
               return(1);
       return(0);
}

digit(s)
{
       register c;

       c = s;
       if(c >='0' && c <= '9')
               return(1);
       return(0);
}

/*
* s is statement
* f is execution flag:
*      0 compile immediate
*      1 compile L
*      2 function definition
*      3 function prolog
*      4 function epilog
*      5 function body
*/
int     ilex[]
{
       lex0, lex1, lex2, lex3, lex4, lex5, lex6
};
compile(s, f)
{
       register char *p, *q;
       char oline[OBJS];

       iline = s;
       ccharp = oline;
       litflag = 0;
       nlexsym = ilex[f];
       context = nlexsym;
       if(yyparse()) {
               pline(s, iline-s);
               return(0);
       }
       *ccharp++ = EOF;
       p = alloc(ccharp-oline);
       iline = p;
       for(q=oline; q<ccharp;)
               *p++ = *q++;
       return(iline);
}

yyerror()
{
}

name(np, c2)
{
       register char *p;

       p = ccharp;
       *ccharp++ = c2;
       *ccharp++ = np.c[0];
       *ccharp++ = np.c[1];
       *ccharp++ = np.c[2];
       *ccharp++ = np.c[3]; 
       return(p);
}

equal(a, b)
char *a, *b;
{
       register char *c1, *c2;

       c1 = a;
       c2 = b;
       while(*c1++ == *c2)
               if(*c2++ == 0)
                       return(1);
       return(0);
}

invert(a, b)
{

       flop(a, b);
       flop(b, ccharp);
       flop(a, ccharp);
}

flop(a, b)
char *a, *b;
{
       register char *a1, *a2;
       register c;

       a1 = a;
       a2 = b;
       while(a1 < a2) {
               c = *a1;
               *a1++ = *--a2;
               *a2 = c; 
       }
}