diplodocus.org Git - nmh/blob - docs/historical/mh-6.8.5/zotnet/tws/phoon/lexstring.c

   1 #include <stdio.h>
   2 #include <ctype.h>
   3
   4 #define YYLERR yysvec
   5 #define YYTYPE int
   6 #define YYLMAX 256
   7
   8 struct yysvf {
   9         struct yywork *yystoff;
  10         struct yysvf *yyother;
  11         int *yystops;
  12 };
  13
  14 struct yywork {
  15         YYTYPE  verify;
  16         YYTYPE  advance;
  17 };
  18
  19 extern int yyvstop[];
  20 extern struct yywork yycrank[];
  21 extern struct yysvf yysvec[];
  22 extern struct yywork *yytop;
  23 extern char yymatch[];
  24 extern char yyextra[];
  25
  26 #ifdef LEXDEBUG
  27 static int debug = 0;
  28 #endif LEXDEBUG
  29
  30 lex_string( strptr, start_cond)
  31         char    **strptr;
  32         int     start_cond;
  33 {
  34         register struct yysvf *state, **lsp;
  35         register struct yywork *tran;
  36         register int ch;
  37         register char   *cp = *strptr;
  38         register int    *found;
  39         struct  yysvf *yylstate[YYLMAX];
  40
  41         /* start off machines */
  42         lsp = yylstate;
  43         state = yysvec+1+start_cond;
  44         for (;;){
  45 # ifdef LEXDEBUG
  46                 if(debug)
  47                         fprintf(stderr,"state %d\n",state-yysvec-1);
  48 # endif
  49                 tran = state->yystoff;
  50                 if(tran == yycrank)
  51                         /* may not be any transitions */
  52                         if (state->yyother == 0 ||
  53                             state->yyother->yystoff == yycrank)
  54                                 break;
  55
  56                 ch = *cp++;
  57 #ifdef ONECASE
  58                 if (isupper(ch) )
  59                         ch = tolower(ch);
  60 #endif ONECASE
  61 tryagain:
  62 # ifdef LEXDEBUG
  63                 if(debug){
  64                         fprintf(stderr,"char ");
  65                         allprint(ch);
  66                         putchar('\n');
  67                 }
  68 # endif
  69                 if ( tran > yycrank){
  70                         tran += ch;
  71                         if (tran <= yytop && tran->verify+yysvec == state){
  72                                 if ((state = tran->advance+yysvec) == YYLERR){
  73                                         /* error transitions */
  74                                         --cp;
  75                                         break;
  76                                 }
  77                                 *lsp++ = state;
  78                                 goto contin;
  79                         }
  80
  81                 } else if(tran < yycrank) {
  82                         /* r < yycrank */
  83                         tran = yycrank+(yycrank-tran) + ch;
  84 # ifdef LEXDEBUG
  85                         if (debug)
  86                                 fprintf(stderr,"compressed state\n");
  87 # endif
  88                         if(tran <= yytop && tran->verify+yysvec == state){
  89                                 if ((state = tran->advance+yysvec) == YYLERR)
  90                                         /* error transitions */
  91                                         break;
  92
  93                                 *lsp++ = state;
  94                                 goto contin;
  95                         }
  96                         tran += (yymatch[ch] - ch);
  97 # ifdef LEXDEBUG
  98                         if(debug){
  99                                 fprintf(stderr,"try fall back character ");
 100                                 allprint(yymatch[ch]);
 101                                 putchar('\n');
 102                         }
 103 # endif
 104                         if(tran <= yytop && tran->verify+yysvec == state){
 105                                 if(tran->advance+yysvec == YYLERR)
 106                                         /* error transition */
 107                                         break;
 108
 109                                 *lsp++ = state = tran->advance+yysvec;
 110                                 goto contin;
 111                         }
 112                 }
 113                 if ((state = state->yyother) &&
 114                     (tran = state->yystoff) != yycrank){
 115 # ifdef LEXDEBUG
 116                         if(debug)
 117                                 fprintf(stderr,"fall back to state %d\n",
 118                                         state-yysvec-1);
 119 # endif
 120                         goto tryagain;
 121                 } else
 122                         break;
 123
 124 contin:
 125 # ifdef LEXDEBUG
 126                 if(debug){
 127                         fprintf(stderr,"state %d char ",state-yysvec-1);
 128                         allprint(ch);
 129                         putchar('\n');
 130                 }
 131 # endif
 132                 ;
 133         }
 134 # ifdef LEXDEBUG
 135         if(debug){
 136                 fprintf(stderr,"stopped at %d with ",*(lsp-1)-yysvec-1);
 137                 allprint(ch);
 138                 putchar('\n');
 139         }
 140 # endif
 141         while (lsp-- > yylstate){
 142                 if (*lsp != 0 && (found= (*lsp)->yystops) && *found > 0){
 143                         if(yyextra[*found]){
 144                                 /* must backup */
 145                                 ch = -*found;
 146                                 do {
 147                                         while (*found && *found++ != ch)
 148                                                 ;
 149                                  } while (lsp > yylstate &&
 150                                           (found = (*--lsp)->yystops));
 151                         }
 152 # ifdef LEXDEBUG
 153                         if(debug){
 154                                 fprintf(stderr,"\nmatch ");
 155                                 for ( cp = *strptr;
 156                                       cp <= ((*strptr)+(lsp-yylstate));
 157                                       cp++)
 158                                         allprint( *cp );
 159                                 fprintf(stderr," action %d\n",*found);
 160                         }
 161 # endif
 162                         *strptr += (lsp - yylstate + 1);
 163                         return(*found);
 164                 }
 165         }
 166         /* the string didn't match anything - if we're looking at
 167          * eos, just return 0.  Otherwise, bump the string pointer
 168          * and return -1.
 169          */
 170 # ifdef LEXDEBUG
 171         if(debug)
 172                 fprintf(stderr,"\nno match\n");
 173 #endif LEXDEBUG
 174         if ( **strptr ) {
 175                 (*strptr)++;
 176                 return (-1);
 177         }
 178         return (0);
 179 }
 180
 181 #ifdef LEXDEBUG
 182 allprint(c)
 183         char c;
 184 {
 185         if ( c < 32 ) {
 186             putc( '^', stderr );
 187             c += 32;
 188         } else if ( c == 127 ) {
 189             putc( '^', stderr );
 190             c = '?';
 191         }
 192         putc( c, stderr );
 193 }
 194 #endif LEXDEBUG