[unix-history] / usr / src / usr.bin / ctags / yacc.c

/*
* Copyright (c) 1987, 1993
*      The Regents of the University of California.  All rights reserved.
*
* %sccs.include.redist.c%
*/

#ifndef lint
static char sccsid[] = "@(#)yacc.c      8.1 (Berkeley) %G%";
#endif /* not lint */

#include <stdio.h>
#include <string.h>
#include "ctags.h"

/*
* y_entries:
*      find the yacc tags and put them in.
*/
y_entries()
{
       register int    c;
       register char   *sp;
       register bool   in_rule;
       char    tok[MAXTOKEN];

       while (GETC(!=,EOF))
               switch ((char)c) {
               case '\n':
                       SETLINE;
                       /* FALLTHROUGH */
               case ' ':
               case '\f':
               case '\r':
               case '\t':
                       break;
               case '{':
                       if (skip_key((int)'}'))
                               in_rule = NO;
                       break;
               case '\'':
               case '"':
                       if (skip_key(c))
                               in_rule = NO;
                       break;
               case '%':
                       if (GETC(==,'%'))
                               return;
                       (void)ungetc(c,inf);
                       break;
               case '/':
                       if (GETC(==,'*'))
                               skip_comment();
                       else
                               (void)ungetc(c,inf);
                       break;
               case '|':
               case ';':
                       in_rule = NO;
                       break;
               default:
                       if (in_rule || !isalpha(c) && c != (int)'.'
                           && c != (int)'_')
                               break;
                       sp = tok;
                       *sp++ = c;
                       while (GETC(!=,EOF) && (intoken(c) || c == (int)'.'))
                               *sp++ = c;
                       *sp = EOS;
                       getline();              /* may change before ':' */
                       while (iswhite(c)) {
                               if (c == (int)'\n')
                                       SETLINE;
                               if (GETC(==,EOF))
                                       return;
                       }
                       if (c == (int)':') {
                               pfnote(tok,lineno);
                               in_rule = YES;
                       }
                       else
                               (void)ungetc(c,inf);
               }
}

/*
* toss_yysec --
*      throw away lines up to the next "\n%%\n"
*/
toss_yysec()
{
       register int    c,                      /* read character */
                       state;

       /*
        * state == 0 : waiting
        * state == 1 : received a newline
        * state == 2 : received first %
        * state == 3 : recieved second %
        */
       lineftell = ftell(inf);
       for (state = 0;GETC(!=,EOF);)
               switch ((char)c) {
                       case '\n':
                               ++lineno;
                               lineftell = ftell(inf);
                               if (state == 3)         /* done! */
                                       return;
                               state = 1;              /* start over */
                               break;
                       case '%':
                               if (state)              /* if 1 or 2 */
                                       ++state;        /* goto 3 */
                               break;
                       default:
                               state = 0;              /* reset */
               }
}