ncform

unix v7是最后一个广泛发布的研究型UNIX版本

int yylineno =1;
# define YYU(x) x
# define NLSTATE yyprevious=YYNEWLINE
char yytext[YYLMAX];
struct yysvf *yylstate [YYLMAX], **yylsp, **yyolsp;
char yysbuf[YYLMAX];
char *yysptr = yysbuf;
int *yyfnd;
extern struct yysvf *yyestate;
int yyprevious = YYNEWLINE;
yylook(){
	register struct yysvf *yystate, **lsp;
	register struct yywork *yyt;
	struct yysvf *yyz;
	int yych;
	struct yywork *yyr;
# ifdef LEXDEBUG
	int debug;
# endif
	char *yylastch;
	/* start off machines */
# ifdef LEXDEBUG
	debug = 0;
# endif
	if (!yymorfg)
		yylastch = yytext;
	else {
		yymorfg=0;
		yylastch = yytext+yyleng;
		}
	for(;;){
		lsp = yylstate;
		yyestate = yystate = yybgin;
		if (yyprevious==YYNEWLINE) yystate++;
		for (;;){
# ifdef LEXDEBUG
			if(debug)fprintf(yyout,"state %d\n",yystate-yysvec-1);
# endif
			yyt = yystate->yystoff;
			if(yyt == yycrank){		/* may not be any transitions */
				yyz = yystate->yyother;
				if(yyz == 0)break;
				if(yyz->yystoff == yycrank)break;
				}
			*yylastch++ = yych = input();
		tryagain:
# ifdef LEXDEBUG
			if(debug){
				fprintf(yyout,"char ");
				allprint(yych);
				putchar('\n');
				}
# endif
			yyr = yyt;
			if ( (int)yyt > (int)yycrank){
				yyt = yyr + yych;
				if (yyt <= yytop && yyt->verify+yysvec == yystate){
					if(yyt->advance+yysvec == YYLERR)	/* error transitions */
						{unput(*--yylastch);break;}
					*lsp++ = yystate = yyt->advance+yysvec;
					goto contin;
					}
				}
# ifdef YYOPTIM
			else if((int)yyt < (int)yycrank) {		/* r < yycrank */
				yyt = yyr = yycrank+(yycrank-yyt);
# ifdef LEXDEBUG
				if(debug)fprintf(yyout,"compressed state\n");
# endif
				yyt = yyt + yych;
				if(yyt <= yytop && yyt->verify+yysvec == yystate){
					if(yyt->advance+yysvec == YYLERR)	/* error transitions */
						{unput(*--yylastch);break;}
					*lsp++ = yystate = yyt->advance+yysvec;
					goto contin;
					}
				yyt = yyr + YYU(yymatch[yych]);
# ifdef LEXDEBUG
				if(debug){
					fprintf(yyout,"try fall back character ");
					allprint(YYU(yymatch[yych]));
					putchar('\n');
					}
# endif
				if(yyt <= yytop && yyt->verify+yysvec == yystate){
					if(yyt->advance+yysvec == YYLERR)	/* error transition */
						{unput(*--yylastch);break;}
					*lsp++ = yystate = yyt->advance+yysvec;
					goto contin;
					}
				}
			if ((yystate = yystate->yyother) && (yyt= yystate->yystoff) != yycrank){
# ifdef LEXDEBUG
				if(debug)fprintf(yyout,"fall back to state %d\n",yystate-yysvec-1);
# endif
				goto tryagain;
				}
# endif
			else
				{unput(*--yylastch);break;}
		contin:
# ifdef LEXDEBUG
			if(debug){
				fprintf(yyout,"state %d char ",yystate-yysvec-1);
				allprint(yych);
				putchar('\n');
				}
# endif
			;
			}
# ifdef LEXDEBUG
		if(debug){
			fprintf(yyout,"stopped at %d with ",*(lsp-1)-yysvec-1);
			allprint(yych);
			putchar('\n');
			}
# endif
		while (lsp-- > yylstate){
			*yylastch-- = 0;
			if (*lsp != 0 && (yyfnd= (*lsp)->yystops) && *yyfnd > 0){
				yyolsp = lsp;
				if(yyextra[*yyfnd]){		/* must backup */
					while(yyback((*lsp)->yystops,-*yyfnd) != 1 && lsp > yylstate){
						lsp--;
						unput(*yylastch--);
						}
					}
				yyprevious = YYU(*yylastch);
				yylsp = lsp;
				yyleng = yylastch-yytext+1;
				yytext[yyleng] = 0;
# ifdef LEXDEBUG
				if(debug){
					fprintf(yyout,"\nmatch ");
					sprint(yytext);
					fprintf(yyout," action %d\n",*yyfnd);
					}
# endif
				return(*yyfnd++);
				}
			unput(*yylastch);
			}
		if (yytext[0] == 0  /* && feof(yyin) */)
			{
			yysptr=yysbuf;
			return(0);
			}
		yyprevious = yytext[0] = input();
		if (yyprevious>0)
			output(yyprevious);
		yylastch=yytext;
# ifdef LEXDEBUG
		if(debug)putchar('\n');
# endif
		}
	}
yyback(p, m)
	int *p;
{
if (p==0) return(0);
while (*p)
	{
	if (*p++ == m)
		return(1);
	}
return(0);
}
	/* the following are only used in the lex library */
yyinput(){
	return(input());
	}
yyoutput(c)
  int c; {
	output(c);
	}
yyunput(c)
   int c; {
	unput(c);
	}