etags.c

早期freebsd实现

    {
    case dnone:
      /* We're not on a preprocessor line. */
      break;
    case dsharpseen:
      if (toktype == st_C_define)
	{
	  definedef = ddefineseen;
	  gotone = FALSE;
	}
      else
	{
	  definedef = dignorerest;
	  gotone = TRUE;
	}
      goto badone;
    case ddefineseen:
      /*
       * Make a tag for any macro.
       * This will flub up if there is a newline immediately following
       * the macro name.
       */
      *is_func = (c == '(');
      definedef = dignorerest;
      gotone = TRUE;
      if (!*is_func && !constantypedefs)
	goto badone;
      goto goodone;
    case dignorerest:
      goto badone;
    default:
      error ("internal error: definedef value");
    }

  /*
   * Skip whitespace and comments after the token.  This loop should
   * also skip C++ comments.
   */
  while (1)
    {
      /* At whitespace => skip it.  */
      if (iswhite (c))
	{
	  c = *lp++;
	}
      /* At a comment => skip to end of comment.  */
      else if (c == '/' && *lp == '*')
	{
	  /* If we find a comment, skip it.  */
	  while (!(c == '*' && *lp == '/'))
	    {
	      c = *lp++;
	      if (c == 0)
		{
		  lp--;
		  break;
		}
	    }
	  if (c == '*' && *lp == '/')
	    {
	      lp++;		/* lp now points past the '/' */
	      c = *lp++;	/* c is now the --whatever-- after the '/' */
	    }
	}
      else
	break;

      /* If we arrived at eof or eol, decide which one it is.
	 If it's eol, advance to the next line.  */

      if (c == 0)
	{
	  lp--;
	  break;
	}
    }

  /*
   * If you have custom token types, or when configuration files can
   * define custom token types, this switch will be larger.
   */
  switch (toktype)
    {
    case st_C_typedef:
      if (typedefs)
	{
	  tydef = begin;
	  goto badone;
	}
      break;
    case st_C_typespec:
      if (tydef == begin || tydef == end)
	{
	  tydef = end;
	  goto badone;
	}
      break;
    }

  /*
   * This structdef business is currently only invoked when level==0.
   * It should be recursively invoked whatever the level, and a stack of
   * states kept, to allow for definitions of structs within structs.
   *
   * This structdef business is NOT invoked when we are ctags and the
   * file is plain C.  This is because a struct tag may have the same
   * name as another tag, and this loses with ctags.
   *
   * This if statement deals with the tydef state machine as follows: if
   * tydef==begin and token is struct/union/class/enum, goto badone.
   * All the other code here is for the structdef state machine.
   */
  switch (toktype)
    {
    case st_C_struct:
    case st_C_enum:
      if (tydef == begin || (typedefs_and_cplusplus && level == 0 && structdef == snone))
	{
	  structdef = skeyseen;
	  structkey = tokse;
	}
      goto badone;
    }

  if (structdef == skeyseen)
    {
      /* If next char is '{' or (for C++) ':', found a structure tag. */
      if (c == '{' || (c_ext && c == ':'))
	{
	  /*
	   * We should do this slightly differently for straight C:
	   * instead of defining `tag', as we now do, we should define
	   * `struct tag'.  (Do this only if the find-tag defaulting is
	   * done on a sophisticated per-mode basis, so that if the user
	   * says meta-. anywhere in `struct foo', the default comes out
	   * `struct foo', not `struct' or `foo'.)  This will require
	   * remembering which keyword (struct/union/class/enum) we saw, as a
	   * Stab_entry* -- this will also make it possible to merge the
	   * skeyseen and senumseen states, if we want.
	   */
	  if (stab_type (structkey) == st_C_struct)
	    {
	      (void) strncpy (structtag, tokp->p, tokp->len);
	      structtag[tokp->len] = '\0';	/* for struct/union/class */
	      structdef = stagseen;
	    }
	  else
	    {
	      structtag[0] = '\0';	/* for enum */
	    }
	  *is_func = FALSE;	/* not a function */
	  goto goodone;
	}
      else
	{
	  /* Not a definition: reset structdef */
	  structdef = snone;
	  (void) strcpy (structtag, "<error 3>");
	}
      /* Now what?  And how does/should this stuff interact with tydef?? */
      /* Also maybe reset lp to *lpp for benefit of the function finding code. */
    }
  if (tydef == begin)
    {
      tydef = end;
      goto badone;
    }
  if (tydef == end)
    {
      *is_func = 0;
      goto goodone;
    }
  /* Detect GNUmacs's function-defining macros. */
  if (definedef == dnone)
    {
      if (strneq (tokp->p, "DEF", 3)
	  || strneq (tokp->p, "ENTRY", 5)
	  || strneq (tokp->p, "SYSCALL", 7)
	  || strneq (tokp->p, "PSEUDO", 6))
	{
	  next_token_is_func = TRUE;
	  goto badone;
	}
      else if (strneq (tokp->p, "EXFUN", 5))
	{
	  next_token_is_func = FALSE;
	  goto badone;
	}
    }
  if (next_token_is_func)
    {
      next_token_is_func = FALSE;
      goto goodone;
    }
  if (c != '(')
    goto badone;
  firsttok = FALSE;
  while ((c = *lp++) != ')')
    {
      if (c == 0)
	{
	  lp--;
	  break;
	}
      /*
	* This line used to confuse ctags:
	*	int	(*oldhup)();
	* This fixes it. A nonwhite char before the first
	* token, other than a / (in case of a comment in there)
	* makes this not a declaration.
	*/
      if (begtoken (c) || c == '/')
	firsttok++;
      else if (!iswhite (c) && !firsttok)
	goto badone;
    }
  while (iswhite (c = *lp++))
    {
      if (c == 0)
	{
	  lp--;
	  break;
	}
    }
  if (!isgood (c))
    goto badone;

goodone:
  *lpp = lp - 1;
  return TRUE;

badone:
  *lpp = lp - 1;
  return FALSE;
}

void
getline (atcookie)
     long atcookie;
{
  long saveftell = ftell (inf);

  (void) fseek (inf, atcookie, 0);
  (void) readline (&lb1, inf);
  (void) fseek (inf, saveftell, 0);
}

/* Fortran parsing */

char *dbp;
int pfcnt;

int
PF_funcs (fi)
     FILE *fi;
{
  lineno = 0;
  charno = 0;
  pfcnt = 0;

  while (!feof (fi))
    {
      lineno++;
      linecharno = charno;
      charno += readline (&lb, fi);
      dbp = lb.buffer;
      if (*dbp == '%')
	dbp++;			/* Ratfor escape to fortran */
      while (isspace (*dbp))
	dbp++;
      if (*dbp == 0)
	continue;
      switch (*dbp | ' ')
	{
	case 'i':
	  if (tail ("integer"))
	    takeprec ();
	  break;
	case 'r':
	  if (tail ("real"))
	    takeprec ();
	  break;
	case 'l':
	  if (tail ("logical"))
	    takeprec ();
	  break;
	case 'c':
	  if (tail ("complex") || tail ("character"))
	    takeprec ();
	  break;
	case 'd':
	  if (tail ("double"))
	    {
	      while (isspace (*dbp))
		dbp++;
	      if (*dbp == 0)
		continue;
	      if (tail ("precision"))
		break;
	      continue;
	    }
	  break;
	}
      while (isspace (*dbp))
	dbp++;
      if (*dbp == 0)
	continue;
      switch (*dbp | ' ')
	{
	case 'f':
	  if (tail ("function"))
	    getit ();
	  continue;
	case 's':
	  if (tail ("subroutine"))
	    getit ();
	  continue;
	case 'p':
	  if (tail ("program"))
	    {
	      getit ();
	      continue;
	    }
	  if (tail ("procedure"))
	    getit ();
	  continue;
	}
    }
  return (pfcnt);
}

logical
tail (cp)
     char *cp;
{
  register int len = 0;

  while (*cp && (*cp & ~' ') == ((*(dbp + len)) & ~' '))
    cp++, len++;
  if (*cp == 0)
    {
      dbp += len;
      return (1);
    }
  return (0);
}

void
takeprec ()
{
  while (isspace (*dbp))
    dbp++;
  if (*dbp != '*')
    return;
  dbp++;
  while (isspace (*dbp))
    dbp++;
  if (!isdigit (*dbp))
    {
      --dbp;			/* force failure */
      return;
    }
  do
    dbp++;
  while (isdigit (*dbp));
}

void
getit ()
{
  register char *cp;
  char c;
  char nambuf[BUFSIZ];

  while (isspace (*dbp))
    dbp++;
  if (*dbp == 0
      || (!isalpha (*dbp)
	  && *dbp != '_'
	  && *dbp != '$'))
    return;
  for (cp = dbp + 1; *cp && (isalpha (*cp) || isdigit (*cp)
			     || (*cp == '_') || (*cp == '$')); cp++)
    continue;
  c = cp[0];
  cp[0] = 0;
  (void) strcpy (nambuf, dbp);
  cp[0] = c;
  pfnote (nambuf, TRUE, FALSE, lb.buffer, cp - lb.buffer + 1, lineno, linecharno);
  pfcnt++;
}

/* Handle a file of assembler code.  */

void
Asm_funcs (fi)
     FILE *fi;
{
  int i;
  register char c;

  lineno = 0;
  charno = 0;
  pfcnt = 0;

  while (!feof (fi))
    {
      lineno++;
      linecharno = charno;
      charno += readline (&lb, fi);
      dbp = lb.buffer;

      for (i = 0; ((c = dbp[i]) && !isspace (c)) && (c != ':'); i++)
	;

      if ((i > 0) && (c == ':'))
	getit ();
    }
}

/* Added by Mosur Mohan, 4/22/88 */
/* Pascal parsing                */

#define GET_NEW_LINE \
{ \
  linecharno = charno; lineno++; \
  charno += 1 + readline (&lb, inf); \
  dbp = lb.buffer; \
}

/*  Locates tags for procedures & functions.
 *  Doesn't do any type- or var-definitions.
 *  It does look for the keyword "extern" or "forward"
 *  immediately following the procedure statement;
 *  if found, the tag is skipped.
 */

void
PAS_funcs (fi)
     FILE *fi;
{
  struct linebuffer tline;	/* mostly copied from C_entries */
  long save_lcno;
  int save_lineno;
  char c, *cp;
  char nambuf[BUFSIZ];

  logical			/* each of these flags is TRUE iff: */
    incomm1,			/* point is inside {..} comment */
    incomm2,			/* point is inside (*..*) comment */
    inquote,			/* point is inside '..' string */
    get_tagname,		/* point is after PROCEDURE/FUNCTION */
  /*   keyword, so next item = potential tag */
    found_tag,			/* point is after a potential tag */
    inparms,			/* point is within parameter-list */
    verify_tag;			/* point has passed the parm-list, so the */
  /*   next token will determine whether    */
  /*   this is a FORWARD/EXTERN to be       */
  /*   ignored, or whether it is a real tag */

  lineno = 0;
  charno = 0;
  dbp = lb.buffer;
  *dbp = 0;
  initbuffer (&tline);

  incomm1 = incomm2 = inquote = FALSE;
  found_tag = FALSE;		/* have a proc name; check if extern */
  get_tagname = FALSE;		/* have found "procedure" keyword    */
  inparms = FALSE;		/* found '(' after "proc"            */
  verify_tag = FALSE;		/* check if "extern" is ahead        */

  /* long main loop to get next char */
  while (!feof (fi))
    {
      c = *dbp++;
      if (c == 0)		/* if end of line */
	{
	  GET_NEW_LINE;
	  if (*dbp == 0)
	    continue;
	  if (!((found_tag && verify_tag) ||
		get_tagname))
	    c = *dbp++;		/* only if don't need *dbp pointing */
	  /* to the beginning of the name of  */
	  /* the procedure or function        */
	}
      if (incomm1)		/* within { - } comments */
	{
	  if (c == '}')
	    incomm1 = FALSE;
	  continue;
	}
      else if (incomm2)		/* within (* - *) comments */
	{
	  if (c == '*')
	    {
	      while ((c = *dbp++) == '*')
		continue;
	      if (c == 0)
		GET_NEW_LINE;
	      if (c == ')')
		incomm2 = FALSE;
	    }
	  continue;
	}
      else if (inquote)
	{
	  if (c == '\'')
	    inquote = FALSE;
	  continue;
	}
      else
	switch (c)
	  {
	  case '\'':
	    inquote = TRUE;	/* found first quote */
	    continue;
	  case '{':		/* found open-{-comment */
	    incomm1 = TRUE;
	    continue;
	  case '(':
	    if (*dbp == '*')	/* found open-(*-comment */
	      {
		incomm2 = TRUE;
		dbp++;
	      }
	    else if (found_tag)	/* found '(' after tag, i.e., parm-list */
	      inparms = TRUE;
	    continue;
	  case ')':		/* end of parms list */
	    if (inparms)
	      inparms = FALSE;
	    continue;
	  case ';':
	    if ((found_tag) && (!inparms))	/* end of proc or fn stmt */
	      {
		verify_tag = TRUE;
		break;
	      }
	    continue;
	  }
      if ((found_tag) && (verify_tag) && (*dbp != ' '))
	{
	  /* check if this is an "extern" declaration */
	  if (*dbp == 0)
	    continue;
	  if ((*dbp == 'e') || (*dbp == 'E'))
	    {
	      if (tail ("extern"))	/* superfluous, really! */
		{
		  found_tag = FALSE;
		  verify_tag = FALSE;
		}
	    }
	  else if ((*dbp == 'f') || (*dbp == 'F'))
	    {
	      if (tail ("forward"))	/*  check for forward reference */
		{
		  found_tag = FALSE;
		  verify_tag = FALSE;
		}
	    }
	  if ((found_tag) && (verify_tag))	/* not external proc, so make tag */
	    {
	      found_tag = FALSE;
	      verify_tag = FALSE;
	      pfnote (nambuf, TRUE, FALSE,
		      tline.buffer, cp - tline.buffer + 1,
		      save_lineno, save_lcno);
	      continue;
	    }
	}
      if (get_tagname)		/* grab name of proc or fn */
	{