[RFA] cfgroot usability improvement

[Ben Elliston <bje@redhat.com>]

The following patch handles the case whereby foolish users (me!) run
sid on a binary file (foo.x) instead of its corresponding
configuration file (foo.x.conf).  If too many non-printable characters
are detected in the input file, sid will stop.

Okay to commit?


2001-05-21  Ben Elliston  <bje@redhat.com>

        * compConfig.cxx (cfgroot_component::num_invalid_chars): New.
        (cfgroot_component ctor): Initialise it.
        (cfgroot_component::consume_token): If num_invalid_chars exceeds
        5, emit an error message and stop.

Index: compConfig.cxx
===================================================================
RCS file: /cvs/cvsfiles/devo/sid/component/cfgroot/compConfig.cxx,v
retrieving revision 1.77
diff -u -c -r1.77 compConfig.cxx
*** compConfig.cxx	2001/03/26 19:18:38	1.77
--- compConfig.cxx	2001/05/21 04:09:15
***************
*** 107,112 ****
--- 107,113 ----
    unsigned line_num;
    bool parse(istream&);
    string current_token;
+   int num_invalid_chars;
    void consume_token(istream&);
    string next_token(istream&);
    bool parse_command(istream&);
***************
*** 255,260 ****
--- 256,266 ----
  	    {
  	      if (!isprint(ch))
  		{
+ 		  if (++num_invalid_chars > 5)
+ 		    {
+ 		      emit_error ("too many invalid characters--possibly a binary file?");
+ 		      exit (1);
+ 		    }
  		  emit_error(string("invalid character [") + 
  			     make_numeric_attribute(host_int_2((unsigned char) ch),
  						    ios::hex|ios::showbase) +
***************
*** 273,278 ****
--- 279,289 ----
  	}
        else // control code
  	{	
+ 	  if (++num_invalid_chars > 5)
+ 	    {
+ 	      emit_error ("too many invalid characters--possibly a binary file?");
+ 	      exit (1);
+ 	    }
  	  emit_error(string("invalid character [") + 
  		     make_numeric_attribute(host_int_2((unsigned char) ch),
  					    ios::hex|ios::showbase) +
***************
*** 545,551 ****
    stop_pin(this, & cfgroot_component::stop),
    verbose_p (false),
    autoprint_p (true),
!   persistent_p (false)
  {
    // suck in libtool preloaded symbols; must be called before lt_dlinit()
    LTDL_SET_PRELOADED_SYMBOLS ();
--- 556,563 ----
    stop_pin(this, & cfgroot_component::stop),
    verbose_p (false),
    autoprint_p (true),
!   persistent_p (false),
!   num_invalid_chars (0)
  {
    // suck in libtool preloaded symbols; must be called before lt_dlinit()
    LTDL_SET_PRELOADED_SYMBOLS ();