\section[lit2doc_for_c]{Document-processing code for language \tr{c}}

\begin{code}
sub rm_embedded_stuff { # return clean code + index entries (\002 separated)
    local($codetxt) = @_;
    
    ($codetxt, '');
}

sub add_code_interests { # DO NOTHING
    # section and blk to record in ($s == -1: don't update) + the code
    local($s, $b, $_) = @_;
    local($defs_to_return) = '';
    local($uses_to_return) = '';
    
    &setup_C_keywords();

    $* = 1; # multi-line searches
    s/^>//g;		# de-Bird-ize
    s/\/\*[^\/]*\*\///g;# de-commentize (necessarily fraught with peril)
    s/\"[^\"\n]*\"//g;	# de-string-ize and de-char-ize
    s/\'[^\'\n]*\'//g;

    # OK, the "interesting" DEFS are #define'd things
    # and things that might be subroutine defns. (3 chars long or more)
    # The latter must begin in col 1!

    while (/^(\s*#define\s+)([A-Za-z_][A-Za-z0-9_]{2,})(\s*)/ ||
           /^([A-Z][a-z]+\s+)?([A-Za-z_][A-Za-z0-9_]{2,})(\([A-Za-z0-9_, ]*\))/) {
    	local($before) = $1;
	local($interesting_thing) = $2; # see hacks below
	local($after) = $3;

#print STDERR "defs=>$before::$interesting_thing::$after::\n";
	local($really_interesting_thing) = (defined($IGNORE_WD{$interesting_thing})) ? '' : $interesting_thing;
	if ($really_interesting_thing) {
	    if ($s != -1) {
		$Blk_codethings_defd[$b] .= "$really_interesting_thing\001";
		$Sec_codethings_defd[$s] .= "$really_interesting_thing\001";
	    } else {
		$defs_to_return .= "$really_interesting_thing\001";
	    }
	}
	# escaping all magic chars in before/interesting/after
	# is v important for avoiding infinite loops! (also below)
	$before =~ s/\s+/\\s\+/g;
	$after =~ s/\s+/\\s\+/g;
	$after =~ s/\(/\\\(/;
	$after =~ s/\)/\\\)/;

	s/$before$interesting_thing$after//g;
    }

    # I AM NOT INTERESTED IN USES AT THE MOMENT
    if ( 0 ) {
	# uses are the same sorts of things
	while (/^(#if\s+|#elif\s+|#else\s+)([A-Za-z_][A-Za-z0-9_]{2,})(\s*)/ || # CPP-ery
	       /(\s*)([A-Za-z_][A-Za-z0-9_]{2,})(\s*)/) {
	    local($before) = $1;
	    local($interesting_thing) = $2; # more hacks below
	    local($after) = $3;

    #print STDERR "uses=>$before::$interesting_thing::$after::\n";

	    local($really_interesting_thing) = (defined($IGNORE_WD{$interesting_thing})) ? '' : $interesting_thing;
	    if ($really_interesting_thing) {
		if ($s != -1) {
		    $Blk_codethings_used[$b] .= "$really_interesting_thing\001";
		    $Sec_codethings_used[$s] .= "$really_interesting_thing\001";
		} else {
		    $uses_to_return .= "$really_interesting_thing\001";
		}
	    }
	    $before =~ s/\s+/\\s\+/g;
	    $interesting_thing =~ s/\$/\\\$/;
	    $interesting_thing =~ s/\@/\\\@/;
	    $interesting_thing =~ s/\%/\\\%/;
	    $after =~ s/\s+/\\s\+/g;

	    s/$before$interesting_thing$after//g;
	}
    }
    $* = 0;

    ($defs_to_return, $uses_to_return);
}

sub setup_C_keywords {
    $IGNORE_WD{'auto'} = 1;
    $IGNORE_WD{'break'} = 1;
    $IGNORE_WD{'case'} = 1;
    $IGNORE_WD{'char'} = 1;
    $IGNORE_WD{'continue'} = 1;
    $IGNORE_WD{'default'} = 1;
    $IGNORE_WD{'do'} = 1;
    $IGNORE_WD{'double'} = 1;
    $IGNORE_WD{'else'} = 1;
    $IGNORE_WD{'entry'} = 1;
    $IGNORE_WD{'extern'} = 1;
    $IGNORE_WD{'float'} = 1;
    $IGNORE_WD{'for'} = 1;
    $IGNORE_WD{'goto'} = 1;
    $IGNORE_WD{'if'} = 1;
    $IGNORE_WD{'int'} = 1;
    $IGNORE_WD{'long'} = 1;
    $IGNORE_WD{'register'} = 1;
    $IGNORE_WD{'return'} = 1;
    $IGNORE_WD{'short'} = 1;
    $IGNORE_WD{'sizeof'} = 1;
    $IGNORE_WD{'static'} = 1;
    $IGNORE_WD{'struct'} = 1;
    $IGNORE_WD{'switch'} = 1;
    $IGNORE_WD{'typedef'} = 1;
    $IGNORE_WD{'union'} = 1;
    $IGNORE_WD{'unsigned'} = 1;
    $IGNORE_WD{'while'} = 1;
#   $IGNORE_WD{''} = 1;
}

# this keeps 'do'ing happy
1;
\end{code}