/* ---------------------- gettoken.c ----------- */

#define GET_H
#include "gettoken.h"

void skip_line() {
   int c;
   while( (c = getchar()) != '\n');
}

/* lexikalische Analyse der Kommandozeile */

TOKEN gettoken(char *word) {
   int c;
   char * w;
   enum {NEUTRAL, TWO_GT, GTGT, INWORD, AMP, OR } state = NEUTRAL;
   w = word;
   while ((c = getchar()) != EOF) {
      switch (state) {
         case NEUTRAL:
            switch (c) {
               case '&':
		  state = AMP;
		  continue;
               case '|':
		  state = OR;
		  continue;
               case '<':
                  return (T_LT);
               case '\n':
		  ungetc(c,stdin);
                  return (T_NL);
               case ' ':
               case '\t':
                  continue;
               case '>':
                  state = GTGT;
                  continue;
               case '2':
                   state = TWO_GT;
                   continue;
               default:
                  state = INWORD;
                  * w++ = c;
                  continue;
            }
         case AMP:
            if (c == '&')
               return (T_AND);
	    skip_line();
	    return (T_AMP);
         case OR:
            if (c == '|')
               return (T_OR);
            ungetc(c,stdin);
            return (T_PIPE);
         case GTGT:
            if (c == '>')
               return (T_GTGT);
            ungetc(c,stdin);
            return (T_GT);
         case TWO_GT:
            if (c == '>')
              return (T_TWO_GT);
            *w++ = '2';
            ungetc(c,stdin);
            state = INWORD;
            continue;
         case INWORD:
            switch (c) {
               case '&':
               case '|':
               case '<':
               case '>':
               case '\n':
               case ' ':
               case '\t':
                  ungetc(c,stdin);
                  * w = '\0';
                  return (T_WORD);
               default:
                  * w++ =c;
                  continue;
            }
      }
   }
   return (T_EOF);
}