sys/src/cmd/lex/ncform

   1 #pragma lib     "libl.a"
   2 int yylineno =1;
   3 # define YYU(x) x
   4 char yytext[YYLMAX];
   5 struct yysvf *yylstate [YYLMAX], **yylsp, **yyolsp;
   6 Uchar yysbuf[YYLMAX];
   7 Uchar *yysptr = yysbuf;
   8 int *yyfnd;
   9 extern struct yysvf *yyestate;
  10 int yyprevious = YYNEWLINE;
  11 # ifdef LEXDEBUG
  12 extern void allprint(int);
  13 # endif
  14 yylook(void){
  15         struct yysvf *yystate, **lsp;
  16         struct yywork *yyt;
  17         struct yysvf *yyz;
  18         int yych;
  19         struct yywork *yyr;
  20 # ifdef LEXDEBUG
  21         int debug;
  22 # endif
  23         Uchar *yylastch;
  24         /* start off machines */
  25 # ifdef LEXDEBUG
  26         debug = 0;
  27 # endif
  28         if (!yymorfg)
  29                 yylastch = (Uchar*)yytext;
  30         else {
  31                 yymorfg=0;
  32                 yylastch = (Uchar*)yytext+yyleng;
  33                 }
  34         for(;;){
  35                 lsp = yylstate;
  36                 yyestate = yystate = yybgin;
  37                 if (yyprevious==YYNEWLINE) yystate++;
  38                 for (;;){
  39 # ifdef LEXDEBUG
  40                         if(debug)fprintf(yyout,"state %d\n",yystate-yysvec-1);
  41 # endif
  42                         yyt = yystate->yystoff;
  43                         if(yyt == yycrank){             /* may not be any transitions */
  44                                 yyz = yystate->yyother;
  45                                 if(yyz == 0)break;
  46                                 if(yyz->yystoff == yycrank)break;
  47                                 }
  48                         *yylastch++ = yych = input();
  49                 tryagain:
  50 # ifdef LEXDEBUG
  51                         if(debug){
  52                                 fprintf(yyout,"char ");
  53                                 allprint(yych);
  54                                 putchar('\n');
  55                                 }
  56 # endif
  57                         yyr = yyt;
  58                         if (yyt > yycrank){
  59                                 yyt = yyr + yych;
  60                                 if (yyt <= yytop && yyt->verify+yysvec == yystate){
  61                                         if(yyt->advance+yysvec == YYLERR)       /* error transitions */
  62                                                 {unput(*--yylastch);break;}
  63                                         *lsp++ = yystate = yyt->advance+yysvec;
  64                                         goto contin;
  65                                         }
  66                                 }
  67 # ifdef YYOPTIM
  68                         else if(yyt < yycrank) {        /* r < yycrank */
  69                                 yyt = yyr = yycrank+(yycrank-yyt);
  70 # ifdef LEXDEBUG
  71                                 if(debug)fprintf(yyout,"compressed state\n");
  72 # endif
  73                                 yyt = yyt + yych;
  74                                 if(yyt <= yytop && yyt->verify+yysvec == yystate){
  75                                         if(yyt->advance+yysvec == YYLERR)       /* error transitions */
  76                                                 {unput(*--yylastch);break;}
  77                                         *lsp++ = yystate = yyt->advance+yysvec;
  78                                         goto contin;
  79                                         }
  80                                 yyt = yyr + YYU(yymatch[yych]);
  81 # ifdef LEXDEBUG
  82                                 if(debug){
  83                                         fprintf(yyout,"try fall back character ");
  84                                         allprint(YYU(yymatch[yych]));
  85                                         putchar('\n');
  86                                         }
  87 # endif
  88                                 if(yyt <= yytop && yyt->verify+yysvec == yystate){
  89                                         if(yyt->advance+yysvec == YYLERR)       /* error transition */
  90                                                 {unput(*--yylastch);break;}
  91                                         *lsp++ = yystate = yyt->advance+yysvec;
  92                                         goto contin;
  93                                         }
  94                                 }
  95                         if ((yystate = yystate->yyother) && (yyt= yystate->yystoff) != yycrank){
  96 # ifdef LEXDEBUG
  97                                 if(debug)fprintf(yyout,"fall back to state %d\n",yystate-yysvec-1);
  98 # endif
  99                                 goto tryagain;
 100                                 }
 101 # endif
 102                         else
 103                                 {unput(*--yylastch);break;}
 104                 contin:
 105 # ifdef LEXDEBUG
 106                         if(debug){
 107                                 fprintf(yyout,"state %d char ",yystate-yysvec-1);
 108                                 allprint(yych);
 109                                 putchar('\n');
 110                                 }
 111 # endif
 112                         ;
 113                         }
 114 # ifdef LEXDEBUG
 115                 if(debug){
 116                         fprintf(yyout,"stopped at %d with ",lsp>yylstate?*(lsp-1)-yysvec-1:0);
 117                         allprint(yych);
 118                         putchar('\n');
 119                         }
 120 # endif
 121                 while (lsp-- > yylstate){
 122                         *yylastch-- = 0;
 123                         if (*lsp != 0 && (yyfnd= (*lsp)->yystops) && *yyfnd > 0){
 124                                 yyolsp = lsp;
 125                                 if(yyextra[*yyfnd]){            /* must backup */
 126                                         while(yyback((*lsp)->yystops,-*yyfnd) != 1 && lsp > yylstate){
 127                                                 lsp--;
 128                                                 unput(*yylastch--);
 129                                                 }
 130                                         }
 131                                 yyprevious = YYU(*yylastch);
 132                                 yylsp = lsp;
 133                                 yyleng = yylastch-(Uchar*)yytext+1;
 134                                 yytext[yyleng] = 0;
 135 # ifdef LEXDEBUG
 136                                 if(debug){
 137                                         fprintf(yyout,"\nmatch '%s'", yytext);
 138                                         fprintf(yyout," action %d\n",*yyfnd);
 139                                         }
 140 # endif
 141                                 return(*yyfnd++);
 142                                 }
 143                         unput(*yylastch);
 144                         }
 145                 if (yytext[0] == 0  /* && feof(yyin) */)
 146                         {
 147                         yysptr=yysbuf;
 148                         return(0);
 149                         }
 150                 yyprevious = input();
 151                 yytext[0] = yyprevious;
 152                 if (yyprevious>0)
 153                         output(yyprevious);
 154                 yylastch = (Uchar*)yytext;
 155 # ifdef LEXDEBUG
 156                 if(debug)putchar('\n');
 157 # endif
 158                 }
 159         }
 160 yyback(int *p, int m)
 161 {
 162 if (p==0) return(0);
 163 while (*p)
 164         {
 165         if (*p++ == m)
 166                 return(1);
 167         }
 168 return(0);
 169 }
 170         /* the following are only used in the lex library */
 171 yyinput(void){
 172         return(input());
 173 }
 174 void
 175 yyoutput(int c)
 176 {
 177         output(c);
 178 }
 179 void
 180 yyunput(int c)
 181 {
 182         unput(c);
 183 }