[help-gengetopt] RE: a small improvement(?) in the config file parser

[Gyozo, PAPP (VBuster)]

" as I understand the right (and consistent with getopt_long) 
" behavior is to use an empty argument if there's only an equal
" sign without anything  after.

Yes, basically this is my intention.

" so the configuration
" 
"  > " [0] = PACKAGE_VAR_NAME
"  > " [1] = "--option-with-arg="
"  > " [2] = "arbitrary"
" 
" is the right one and it results in the same output as if we 
" would have passed that command line, am I right?

Yes.

" If so, could you please send me the patch that corrects this 
" problem? :-)


I'll send a patch against the original 2.13 and not the recent 2.13rc1.
It also includes the the compilation warnings elimination and the fix of the 
uninitialized `result' variable in _required() function.
What is more important is this patch contains another bug fix in the config 
parser I've overlooked for a long time.

<code to be replaced somewhere around the line 360 in src/skels/c_source.h_skel>

      /* truncate fopt at the end of the first non-valid character */
      next_token = strcspn (fopt, " \t\r\n=");

      if (fopt[next_token] == '\0') /* the line is over */
        {
          farg  = NULL;
          goto noarg;
        }

      fopt[next_token++] = '\0';

      /* advance pointers to the next token after the end of fopt */
      next_token += strspn (fopt + next_token, " \t\r\n#");
      str_index += next_token;

</code to be replaced>

Erroneously, '#' was part of the token delimiter character rather than treating 
it as the first character of a new token (comment).
Now the code above has been replaced with the following one:

      /* truncate fopt at the end of the first non-valid character */
      next_token = strcspn (fopt, " \t\r\n=");

      if (fopt[next_token] == '\0') /* the line is over */
        {
          farg  = NULL;
          equal = 0;
          goto noarg;
        }

      /* remember if equal sign is present */
      equal = (fopt[next_token] == '=');
      fopt[next_token++] = '\0';

      /* advance pointers to the next token after the end of fopt */
      next_token += strspn (fopt + next_token, " \t\r\n");
      /* check for the presence of equal sign, and if so, skip it */
      if ( !equal )
        if ((equal = (fopt[next_token] == '=')))
          {
            next_token++;
            next_token += strspn (fopt + next_token, " \t\r\n");
          }
      str_index += next_token;

It may also be good to know that the current implementation does always be 
aware of the presence or absence of the '=', because, in my understanding, the 
'=' has become a new token rather than a simple delimiter or a "syntactic 
sugar". This complicates the original source a little, but I hope this will 
result a more user friendly config parser.


Gyozo

config2.patch
Description: config2.patch