From 1eda41862b7279427ab2da51b8dd12767118bfa4 Mon Sep 17 00:00:00 2001 From: Niko Tyni Date: Wed, 9 Mar 2005 17:17:06 +0000 Subject: * change all ISG::ParseConfig references to its new name, Config::Grammar --- lib/Config/Grammar.pm | 1502 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1502 insertions(+) create mode 100644 lib/Config/Grammar.pm (limited to 'lib/Config/Grammar.pm') diff --git a/lib/Config/Grammar.pm b/lib/Config/Grammar.pm new file mode 100644 index 0000000..ede1a48 --- /dev/null +++ b/lib/Config/Grammar.pm @@ -0,0 +1,1502 @@ +package Config::Grammar; + +# TODO: +# - _order for sections + +use strict; + +use vars qw($VERSION); +$VERSION = '1.01'; + +sub new($$) +{ + my $proto = shift; + my $grammar = shift; + my $class = ref($proto) || $proto; + + my $self = {grammar => $grammar}; + bless($self, $class); + return $self; +} + +sub err($) +{ + my $self = shift; + return $self->{'err'}; +} + +sub _make_error($$) +{ + my $self = shift; + my $text = shift; + $self->{'err'} = "$self->{file}, line $self->{line}: $text"; +} + +sub _peek($) +{ + my $a = shift; + return $a->[$#$a]; +} + +sub _quotesplit($) +{ + my $line = shift; + my @items; + while ($line ne "") { + if ($line =~ s/^"((?:\\.|[^"])*)"\s*//) { + my $frag = $1; + $frag =~ s/\\(.)/$1/g; + push @items, $frag; + } elsif ($line =~ s/^'((?:\\.|[^'])*)'\s*//) { + my $frag = $1; + $frag =~ s/\\(.)/$1/g; + push @items, $frag; + } + elsif ($line =~ s/^((?:\\.|[^\s])*)(?:\s+|$)//) { + my $frag = $1; + $frag =~ s/\\(.)/$1/g; + push @items, $frag; + } + else { + die "Internal parser error for '$line'\n"; + } + } + return @items; +} + +sub _deepcopy { + # this handles circular references on consecutive levels, + # but breaks if there are any levels in between + # the makepod() and maketmpl() methods have the same limitation + my $what = shift; + return $what unless ref $what; + for (ref $what) { + /^ARRAY$/ and return [ map { $_ eq $what ? $_ : _deepcopy($_) } @$what ]; + /^HASH$/ and return { map { $_ => $what->{$_} eq $what ? + $what->{$_} : _deepcopy($what->{$_}) } keys %$what }; + /^CODE$/ and return $what; # we don't need to copy the subs + /^Regexp$/ and return $what; # neither Regexp objects + } + die "Cannot _deepcopy reference type @{[ref $what]}"; +} + +sub _check_mandatory($$$$) +{ + my $self = shift; + my $g = shift; + my $c = shift; + my $section = shift; + + # check _mandatory sections, variables and tables + if (defined $g->{_mandatory}) { + for (@{$g->{_mandatory}}) { + if (not defined $g->{$_}) { + $g->{$_} = {}; + +#$self->{'err'} = "ParseConfig internal error: mandatory name $_ not found in grammar"; + #return 0; + } + if (not defined $c->{$_}) { + if (defined $section) { + $self->{'err'} .= "$self->{file} ($section): "; + } + else { + $self->{'err'} = "$self->{file}: "; + } + + if (defined $g->{$_}{_is_section}) { + $self->{'err'} .= "mandatory (sub)section '$_' not defined"; + } + elsif ($_ eq '_table') { + $self->{'err'} .= "mandatory table not defined"; + } + else { + $self->{'err'} .= "mandatory variable '$_' not defined"; + } + return 0; + } + } + } + + for (keys %$c) { + + # do some cleanup + ref $c->{$_} eq 'HASH' or next; + defined $c->{$_}{_is_section} or next; + $self->_check_mandatory($g->{$c->{$_}{_grammar}}, $c->{$_}, + defined $section ? "$section/$_" : "$_") or return 0; + delete $c->{$_}{_is_section}; + delete $c->{$_}{_grammar}; + delete $c->{$_}{_order_count} if exists $c->{$_}{_order_count}; + } + + return 1; +} + +######### SECTIONS ######### + +# search grammar definition of a section +sub _search_section($$) +{ + my $self = shift; + my $name = shift; + + if (not defined $self->{grammar}{_sections}) { + $self->_make_error("no sections are allowed"); + return undef; + } + + # search exact match + for (@{$self->{grammar}{_sections}}) { + if ($name eq $_) { + return $_; + } + } + + # search regular expression + for (@{$self->{grammar}{_sections}}) { + if (m|^/(.*)/$|) { + if ($name =~ /^$1$/) { + return $_; + } + } + } + + # no match + $self->_make_error("unknown section '$name'"); + return undef; +} + +# fill in default values for this section +sub _fill_defaults ($) { + my $self = shift; + my $g = $self->{grammar}; + my $c = $self->{cfg}; + if ($g->{_vars}) { + for my $var (@{$g->{_vars}}) { + next if exists $c->{$var}; + my $value = $g->{$var}{_default} + if exists $g->{$var}{_default}; + next unless defined $value; + $c->{$var} = $value; + } + } + +} + +sub _next_level($$$) +{ + my $self = shift; + my $name = shift; + + # section name + if (defined $self->{section}) { + $self->{section} .= "/$name"; + } + else { + $self->{section} = $name; + } + + # grammar context + my $s = $self->_search_section($name); + return 0 unless defined $s; + if (not defined $self->{grammar}{$s}) { + $self->_make_error("ParseConfig internal error (no grammar for $s)"); + return 0; + } + push @{$self->{grammar_stack}}, $self->{grammar}; + if ($s =~ m|^/(.*)/$|) { + # for sections specified by a regexp, we create + # a new branch with a deep copy of the section + # grammar so that any _dyn sub further below will edit + # just this branch + + $self->{grammar}{$name} = _deepcopy($self->{grammar}{$s}); + + # put it at the head of the section list + $self->{grammar}{_sections} ||= []; + unshift @{$self->{grammar}{_sections}}, $name; + } + + # support for recursive sections + # copy the section syntax to the subsection + + if ($self->{grammar}{_recursive} + and grep { $_ eq $s } @{$self->{grammar}{_recursive}}) { + $self->{grammar}{$name}{_sections} ||= []; + $self->{grammar}{$name}{_recursive} ||= []; + push @{$self->{grammar}{$name}{_sections}}, $s; + push @{$self->{grammar}{$name}{_recursive}}, $s; + my $grammarcopy = _deepcopy($self->{grammar}{$name}); + if (exists $self->{grammar}{$name}{$s}) { + # there's syntax for a variable by the same name too + # make sure we don't lose it + %{$self->{grammar}{$name}{$s}} = ( %$grammarcopy, %{$self->{grammar}{$name}{$s}} ); + } else { + $self->{grammar}{$name}{$s} = $grammarcopy; + } + } + + # this uses the copy created above for regexp sections + # and the original for non-regexp sections (where $s == $name) + $self->{grammar} = $self->{grammar}{$name}; + + # support for inherited values + # note that we have to do this on the way down + # and keep track of which values were inherited + # so that we can propagate the values even further + # down if needed + my %inherited; + if ($self->{grammar}{_inherited}) { + for my $var (@{$self->{grammar}{_inherited}}) { + next unless exists $self->{cfg}{$var}; + my $value = $self->{cfg}{$var}; + next unless defined $value; + next if ref $value; # it's a section + $inherited{$var} = $value; + } + } + + # config context + my $order; + if (defined $self->{grammar}{_order}) { + if (defined $self->{cfg}{_order_count}) { + $order = ++$self->{cfg}{_order_count}; + } + else { + $order = $self->{cfg}{_order_count} = 0; + } + } + + if (defined $self->{cfg}{$name}) { + $self->_make_error('section or variable already exists'); + return 0; + } + $self->{cfg}{$name} = { %inherited }; # inherit the values + push @{$self->{cfg_stack}}, $self->{cfg}; + $self->{cfg} = $self->{cfg}{$name}; + + # keep track of the inherited values here; + # we delete it on the way up in _prev_level() + $self->{cfg}{_inherited} = \%inherited; + + # list of already defined variables on this level + if (defined $self->{grammar}{_varlist}) { + $self->{cfg}{_varlist} = []; + } + + # meta data for _mandatory test + $self->{grammar}{_is_section} = 1; + $self->{cfg}{_is_section} = 1; + + # this uses the copy created above for regexp sections + # and the original for non-regexp sections (where $s == $name) + $self->{cfg}{_grammar} = $name; + + $self->{cfg}{_order} = $order if defined $order; + + # increase level + $self->{level}++; + + # if there's a _dyn sub, apply it + if (defined $self->{grammar}{_dyn}) { + &{$self->{grammar}{_dyn}}($s, $name, $self->{grammar}); + } + + return 1; +} + +sub _prev_level($) +{ + my $self = shift; + + # fill in the values from _default keywords when going up + $self->_fill_defaults; + + # section name + if (defined $self->{section}) { + if ($self->{section} =~ /\//) { + $self->{section} =~ s/\/.*?$//; + } + else { + $self->{section} = undef; + } + } + + # clean up the _inherited hash, we won't need it anymore + delete $self->{cfg}{_inherited}; + + # config context + $self->{cfg} = pop @{$self->{cfg_stack}}; + + # grammar context + $self->{grammar} = pop @{$self->{grammar_stack}}; + + # decrease level + $self->{level}--; +} + +sub _goto_level($$$) +{ + my $self = shift; + my $level = shift; + my $name = shift; + + # _text is multi-line. Check when changing level + $self->_check_text($self->{section}) or return 0; + + if ($level > $self->{level}) { + if ($level > $self->{level} + 1) { + $self->_make_error("section nesting error"); + return 0; + } + $self->_next_level($name) or return 0; + } + else { + + while ($self->{level} > $level) { + $self->_prev_level; + } + if ($level != 0) { + $self->_prev_level; + $self->_next_level($name) or return 0; + } + } + + return 1; +} + +######### VARIABLES ######### + +# search grammar definition of a variable +sub _search_variable($$) +{ + my $self = shift; + my $name = shift; + + if (not defined $self->{grammar}{_vars}) { + $self->_make_error("no variables are allowed"); + return undef; + } + + # search exact match + for (@{$self->{grammar}{_vars}}) { + if ($name eq $_) { + return $_; + } + } + + # search regular expression + for (@{$self->{grammar}{_vars}}) { + if (m|^/(.*)/$|) { + if ($name =~ /^$1$/) { + return $_; + } + } + } + + # no match + $self->_make_error("unknown variable '$name'"); + return undef; +} + +sub _set_variable($$$) +{ + my $self = shift; + my $key = shift; + my $value = shift; + + my $gn = $self->_search_variable($key); + defined $gn or return 0; + + my $varlistref; + if (defined $self->{grammar}{_varlist}) { + $varlistref = $self->{cfg}{_varlist}; + } + + if (defined $self->{grammar}{$gn}) { + my $g = $self->{grammar}{$gn}; + + # check regular expression + if (defined $g->{_re}) { + $value =~ /^$g->{_re}$/ or do { + if (defined $g->{_re_error}) { + $self->_make_error($g->{_re_error}); + } + else { + $self->_make_error("syntax error in value of '$key'"); + } + return 0; + } + } + if (defined $g->{_sub}){ + my $error = &{$g->{_sub}}($value, $varlistref); + if (defined $error){ + $self->_make_error($error); + return 0; + } + } + # if there's a _dyn sub, apply it + if (defined $g->{_dyn}) { + &{$g->{_dyn}}($key, $value, $self->{grammar}); + } + } + $self->{cfg}{$key} = $value; + push @{$varlistref}, $key if ref $varlistref; + + return 1; +} + +######### PARSER ######### + +sub _parse_table($$) +{ + my $self = shift; + local $_ = shift; + + my $g = $self->{grammar}{_table}; + defined $g or do { + $self->_make_error("table syntax error"); + return 0; + }; + + my @l = _quotesplit $_; + + # check number of columns + my $columns = $g->{_columns}; + if (defined $columns and $#l + 1 != $columns) { + $self->_make_error("row must have $columns columns (has " . ($#l + 1) + . ")"); + return 0; + } + + # check columns + my $n = 0; + for my $c (@l) { + my $gc = $g->{$n}; + defined $gc or next; + + # regular expression + if (defined $gc->{_re}) { + $c =~ /^$gc->{_re}$/ or do { + if (defined $gc->{_re_error}) { + $self->_make_error($gc->{_re_error}); + } + else { + $self->_make_error("syntax error in column $n"); + } + return 0; + }; + } + if (defined $gc->{_sub}){ + my $error = &{$gc->{_sub}}($c); + if (defined $error) { + $self->_make_error($error); + return 0; + } + } + $n++; + } + + # hash (keyed table) + if (defined $g->{_key}) { + my $kn = $g->{_key}; + if ($kn < 0 or $kn > $#l) { + $self->_make_error("grammar error: key out of bounds"); + } + my $k = $l[$kn]; + + if (defined $self->{cfg}{$k}) { + $self->_make_error("table row $k already defined"); + return 0; + } + $self->{cfg}{$k} = \@l; + } + + # list (unkeyed table) + else { + push @{$self->{cfg}{_table}}, \@l; + } + + return 1; +} + +sub _parse_text($$) +{ + my ($self, $line) = @_; + + $self->{cfg}{_text} .= $line; + + return 1; +} + +sub _check_text($$) +{ + my ($self, $name) = @_; + + my $g = $self->{grammar}{_text}; + defined $g or return 1; + + # chop empty lines at beginning and end + if(defined $self->{cfg}{_text}) { + $self->{cfg}{_text} =~ s/\A([ \t]*[\n\r]+)*//m; + $self->{cfg}{_text} =~ s/^([ \t]*[\n\r]+)*\Z//m; + } + + # TODO: not good for META. Use _mandatory ? + #defined $self->{cfg}{_text} or do { + # $self->_make_error("value of '$name' not defined"); + # return 0; + #}; + + if (defined $g->{_re}) { + $self->{cfg}{_text} =~ /^$g->{_re}$/ or do { + if (defined $g->{_re_error}) { + $self->_make_error($g->{_re_error}); + } + else { + $self->_make_error("syntax error"); + } + return 0; + } + } + if (defined $g->{_sub}){ + my $error = &{$g->{_sub}}($self->{cfg}{_text}); + if (defined $error) { + $self->_make_error($error); + return 0; + } + } + return 1; +} + +sub _parse_file($$); + +sub _parse_line($$$) +{ + my $self = shift; + local $_ = shift; + my $source = shift; + + /^\@include\s+["']?(.*)["']?$/ and do { + push @{$self->{file_stack}}, $self->{file}; + push @{$self->{line_stack}}, $self->{line}; + $self->_parse_file($1) or return 0; + $self->{file} = pop @{$self->{file_stack}}; + $self->{line} = pop @{$self->{line_stack}}; + return 1; + }; + /^\@define\s+(\S+)\s+(.*)$/ and do { + $self->{defines}{$1}=quotemeta $2; + return 1; + }; + + if(defined $self->{defines}) { + for my $d (keys %{$self->{defines}}) { + s/$d/$self->{defines}{$d}/g; + } + } + + /^\*\*\*\s*(.*?)\s*\*\*\*$/ and do { + my $name = $1; + $self->_goto_level(1, $name) or return 0; + $self->_check_section_sub($name) or return 0; + return 1; + }; + /^(\++)\s*(.*)$/ and do { + my $level = length $1; + my $name = $2; + $self->_goto_level($level + 1, $name) or return 0; + $self->_check_section_sub($name) or return 0; + return 1; + }; + + if (defined $self->{grammar}{_text}) { + $self->_parse_text($source) or return 0; + return 1; + } + /^(\S+)\s*=\s*(.*)$/ and do { + if (defined $self->{cfg}{$1}) { + if (exists $self->{cfg}{_inherited}{$1}) { + # it's OK to override any inherited values + delete $self->{cfg}{_inherited}{$1}; + delete $self->{cfg}{$1}; + } else { + $self->_make_error('variable already defined'); + return 0; + } + } + $self->_set_variable($1, $2) or return 0; + return 1; + }; + + $self->_parse_table($_) or return 0; + + return 1; +} + +sub _check_section_sub($$) { + my $self = shift; + my $name = shift; + my $g = $self->{grammar}; + if (defined $g->{_sub}){ + my $error = &{$g->{_sub}}($name); + if (defined $error){ + $self->_make_error($error); + return 0; + } + } + return 1; +} + +sub _parse_file($$) +{ + my $self = shift; + my $file = shift; + + local *File; + unless ($file) { $self->{'err'} = "no filename given" ; + return undef;}; + + open(File, "$file") or do { + $self->{'err'} = "can't open $file: $!"; + return undef; + }; + $self->{file} = $file; + + local $_; + my $source = ''; + while () { + $source .= $_; + chomp; + s/^\s+//; + s/\s+$//; # trim + s/\s*#.*$//; # comments + next if $_ eq ''; # empty lines + while (/\\$/) {# continuation + s/\\$//; + my $n = ; + last if not defined $n; + chomp $n; + $n =~ s/^\s+//; + $n =~ s/\s+$//; # trim + $_ .= ' ' . $n; + } + + $self->{line} = $.; + $self->_parse_line($_, $source) or do{ close File; return 0; }; + $source = ''; + } + close File; + return 1; +} + +# find variables in old grammar list 'listname' +# that aren't in the corresponding list in the new grammar +# and list them as a POD document, possibly with a callback +# function 'docfunc' + +sub _findmissing($$$;$) { + my $old = shift; + my $new = shift; + my $listname = shift; + my $docfunc = shift; + + my @doc; + if ($old->{$listname}) { + my %newlist; + if ($new->{$listname}) { + @newlist{@{$new->{$listname}}} = undef; + } + for my $v (@{$old->{$listname}}) { + next if exists $newlist{$v}; + if ($docfunc) { + push @doc, &$docfunc($old, $v) + } else { + push @doc, "=item $v"; + } + } + } + return @doc; +} + +# find variables in new grammar list 'listname' +# that aren't in the corresponding list in the new grammar +# +# this is just _findmissing with the arguments swapped + +sub _findnew($$$;$) { + my $old = shift; + my $new = shift; + my $listname = shift; + my $docfunc = shift; + return _findmissing($new, $old, $listname, $docfunc); +} + +# compare two lists for element equality + +sub _listseq($$); +sub _listseq($$) { + my ($k, $l) = @_; + my $length = @$k; + return 0 unless @$l == $length; + for (my $i=0; $i<$length; $i++) { + return 0 unless $k->[$i] eq $l->[$i]; + } + return 1; +} + +# diff two grammar trees, documenting the differences + +sub _diffgrammars($$); +sub _diffgrammars($$) { + my $old = shift; + my $new = shift; + my @doc; + + my @vdoc; + @vdoc = _findmissing($old, $new, '_vars'); + push @doc, "The following variables are not valid anymore:", "=over" , @vdoc, "=back" + if @vdoc; + @vdoc = _findnew($old, $new, '_vars', \&_describevar); + push @doc, "The following new variables are valid:", "=over" , @vdoc, "=back" + if @vdoc; + @vdoc = _findmissing($old, $new, '_sections'); + push @doc, "The following subsections are not valid anymore:", "=over" , @vdoc, "=back" + if @vdoc; + @vdoc = _findnew($old, $new, '_sections', sub { + my ($tree, $sec) = @_; + my @tdoc; + _genpod($tree->{$sec}, 0, \@tdoc); + return @tdoc; + }); + push @doc, "The following new subsections are defined:", "=over" , @vdoc, "=back" + if @vdoc; + for (@{$old->{_sections}}) { + next unless exists $new->{$_}; + @vdoc = _diffgrammars($old->{$_}, $new->{$_}); + push @doc, "Syntax changes for subsection B<$_>", "=over", @vdoc, "=back" + if @vdoc; + } + return @doc; +} + +# describe a variable + +sub _describevar { + my $tree = shift; + my $var = shift; + my $mandatory = ( $tree->{_mandatory} and + grep {$_ eq $var} @{$tree->{_mandatory}} ) ? + " I<(mandatory setting)>" : ""; + my @doc; + push @doc, "=item B<$var>".$mandatory; + push @doc, $tree->{$var}{_doc} if $tree->{$var}{_doc} ; + my $inherited = ( $tree->{_inherited} and + grep {$_ eq $var} @{$tree->{_inherited}}); + push @doc, "This variable I its value from the parent section if nothing is specified here." + if $inherited; + push @doc, "This variable I modifies the grammar based on its value." + if $tree->{$var}{_dyn}; + push @doc, "Default value: $var = $tree->{$var}{_default}" + if ($tree->{$var}{_default}); + push @doc, "Example: $var = $tree->{$var}{_example}" + if ($tree->{$var}{_example}); + return @doc; +} + +sub _genpod($$$); +sub _genpod($$$){ + my $tree = shift; + my $level = shift; + my $doc = shift; + my %dyndoc; + if ($tree->{_vars}){ + push @{$doc}, "The following variables can be set in this section:"; + push @{$doc}, "=over"; + foreach my $var (@{$tree->{_vars}}){ + push @{$doc}, _describevar($tree, $var); + } + push @{$doc}, "=back"; + } + + if ($tree->{_text}){ + push @{$doc}, ($tree->{_text}{_doc} or "Unspecified Text content"); + if ($tree->{_text}{_example}){ + my $ex = $tree->{_text}{_example}; + chomp $ex; + $ex = map {" $_"} split /\n/, $ex; + push @{$doc}, "Example:\n\n$ex\n"; + } + } + + if ($tree->{_table}){ + push @{$doc}, ($tree->{_table}{_doc} or + "This section can contain a table ". + "with the following structure:" ); + push @{$doc}, "=over"; + for (my $i=0;$i < $tree->{_table}{_columns}; $i++){ + push @{$doc}, "=item column $i"; + push @{$doc}, ($tree->{_table}{$i}{_doc} or + "Unspecific Content"); + push @{$doc}, "Example: $tree->{_table}{$i}{_example}" + if ($tree->{_table}{$i}{_example}) + } + push @{$doc}, "=back"; + } + if ($tree->{_sections}){ + if ($level > 0) { + push @{$doc}, "The following sections are valid on level $level:"; + push @{$doc}, "=over"; + } + foreach my $section (@{$tree->{_sections}}){ + my $mandatory = ( $tree->{_mandatory} and + grep {$_ eq $section} @{$tree->{_mandatory}} ) ? + " I<(mandatory section)>" : ""; + push @{$doc}, ($level > 0) ? + "=item B<".("+" x $level)."$section>$mandatory" : + "=head2 *** $section ***$mandatory"; + if ($tree eq $tree->{$section}) { + push @{$doc}, "This subsection has the same syntax as its parent."; + next; + } + push @{$doc}, ($tree->{$section}{_doc}) + if $tree->{$section}{_doc}; + push @{$doc}, "The grammar of this section is I modified based on its name." + if $tree->{$section}{_dyn}; + if ($tree->{_recursive} and + grep {$_ eq $section} @{$tree->{_recursive}}) { + push @{$doc}, "This section is I: it can contain subsection(s) with the same syntax."; + } + _genpod ($tree->{$section},$level+1,$doc); + next unless $tree->{$section}{_dyn} and $tree->{$section}{_dyndoc}; + push @{$doc}, "Dynamical grammar changes for example instances of this section:"; + push @{$doc}, "=over"; + for my $name (sort keys %{$tree->{$section}{_dyndoc}}) { + my $newtree = _deepcopy($tree->{$section}); + push @{$doc}, "=item B<$name>: $tree->{$section}{_dyndoc}{$name}"; + &{$tree->{$section}{_dyn}}($section, $name, $newtree); + my @tdoc = _diffgrammars($tree->{$section}, $newtree); + if (@tdoc) { + push @{$doc}, @tdoc; + } else { + push @{$doc}, "No changes that can be automatically described."; + } + push @{$doc}, "(End of dynamical grammar changes for example instance C<$name>.)"; + } + push @{$doc}, "=back"; + push @{$doc}, "(End of dynamical grammar changes for example instances of section C<$section>.)"; + } + push @{$doc}, "=back" if $level > 0 + } + if ($tree->{_vars}) { + for my $var (@{$tree->{_vars}}) { + next unless $tree->{$var}{_dyn} and $tree->{$var}{_dyndoc}; + push @{$doc}, "Dynamical grammar changes for example values of variable C<$var>:"; + push @{$doc}, "=over"; + for my $val (sort keys %{$tree->{$var}{_dyndoc}}) { + my $newtree = _deepcopy($tree); + push @{$doc}, "=item B<$val>: $tree->{$var}{_dyndoc}{$val}"; + &{$tree->{$var}{_dyn}}($var, $val, $newtree); + my @tdoc = _diffgrammars($tree, $newtree); + if (@tdoc) { + push @{$doc}, @tdoc; + } else { + push @{$doc}, "No changes that can be automatically described."; + } + push @{$doc}, "(End of dynamical grammar changes for variable C<$var> example value C<$val>.)"; + } + push @{$doc}, "=back"; + push @{$doc}, "(End of dynamical grammar changes for example values of variable C<$var>.)"; + } + } +}; + +sub makepod($) { + my $self = shift; + my $tree = $self->{grammar}; + my @doc; + _genpod $tree,0,\@doc; + return join("\n\n", @doc)."\n"; +} + +sub _gentmpl($$$@); +sub _gentmpl($$$@){ + my $tree = shift; + my $level = shift; + my $doc = shift; + my @start = @_; + if (scalar @start ) { + my $section = shift @start; + my $secex =''; + my $prefix = ''; + $prefix = "# " unless $tree->{_mandatory} and + grep {$_ eq $section} @{$tree->{_mandatory}}; + if ($tree->{$section}{_example}) { + $secex = " # ( ex. $tree->{$section}{_example} )"; + } + push @{$doc}, $prefix. + (($level > 0) ? ("+" x $level)."$section" : "*** $section ***").$secex; + my $match; + foreach my $s (@{$tree->{_sections}}){ + if ($s =~ m|^/.+/$| and $section =~ /$s/ or $s eq $section) { + _gentmpl ($tree->{$s},$level+1,$doc,@start) + unless $tree eq $tree->{$s}; + $match = 1; + } + } + push @{$doc}, "# Section $section is not a valid choice" + unless $match; + } else { + if ($tree->{_vars}){ + foreach my $var (@{$tree->{_vars}}){ + push @{$doc}, "# $var = ". + ($tree->{$var}{_example} || ' * no example *'); + next unless $tree->{_mandatory} and + grep {$_ eq $var} @{$tree->{_mandatory}}; + push @{$doc}, "$var="; + } + } + + if ($tree->{_text}){ + if ($tree->{_text}{_example}){ + my $ex = $tree->{_text}{_example}; + chomp $ex; + $ex = map {"# $_"} split /\n/, $ex; + push @{$doc}, "$ex\n"; + } + } + if ($tree->{_table}){ + my $table = "# table\n#"; + for (my $i=0;$i < $tree->{_table}{_columns}; $i++){ + $table .= ' "'.($tree->{_table}{$i}{_example} || "C$i").'"'; + } + push @{$doc}, $table; + } + if ($tree->{_sections}){ + foreach my $section (@{$tree->{_sections}}){ + my $opt = ( $tree->{_mandatory} and + grep {$_ eq $section} @{$tree->{_mandatory}} ) ? + "":"\n# optional section\n"; + my $prefix = ''; + $prefix = "# " unless $tree->{_mandatory} and + grep {$_ eq $section} @{$tree->{_mandatory}}; + my $secex =""; + if ($section =~ m|^/.+/$| && $tree->{$section}{_example}) { + $secex = " # ( ex. $tree->{$section}{_example} )"; + } + push @{$doc}, $prefix. + (($level > 0) ? ("+" x $level)."$section" : "*** $section ***"). + $secex; + _gentmpl ($tree->{$section},$level+1,$doc,@start) + unless $tree eq $tree->{$section}; + } + } + } +}; + +sub maketmpl ($@) { + my $self = shift; + my @start = @_; + my $tree = $self->{grammar}; + my @tmpl; + _gentmpl $tree,0,\@tmpl,@start; + return join("\n", @tmpl)."\n"; +} + +sub parse($$) +{ + my $self = shift; + my $file = shift; + + $self->{cfg} = {}; + $self->{level} = 0; + $self->{cfg_stack} = []; + $self->{grammar_stack} = []; + $self->{file_stack} = []; + $self->{line_stack} = []; + + # we work with a copy of the grammar so the _dyn subs may change it + local $self->{grammar} = _deepcopy($self->{grammar}); + + $self->_parse_file($file) or return undef; + + $self->_goto_level(0, undef) or return undef; + + # fill in the top level values from _default keywords + $self->_fill_defaults; + + $self->_check_mandatory($self->{grammar}, $self->{cfg}, undef) + or return undef; + + return $self->{cfg}; + +} + +1 + +__END__ + +=head1 NAME + +Config::Grammar - A grammar-based, user-friendly config parser + +=head1 SYNOPSIS + + use Config::Grammar; + + my $parser = Config::Grammar->new(\%grammar); + my $cfg = $parser->parse('app.cfg') or die "ERROR: $parser->{err}\n"; + my $pod = $parser->makepod(); + my $ex = $parser->maketmpl('TOP','SubNode'); + +=head1 DESCRIPTION + +Config::Grammar is a module to parse configuration files. The +configuration may consist of multiple-level sections with assignments +and tabular data. The parsed data will be returned as a hash +containing the whole configuration. Config::Grammar uses a grammar +that is supplied upon creation of a Config::Grammar object to parse +the configuration file and return helpful error messages in case of +syntax errors. Using the B method you can generate +documentation of the configuration file format. + +The B method can generate a template configuration file. If +your grammar contains regexp matches, the template will not be all +that helpful as ParseConfig is not smart enough to give you sensible +template data based in regular expressions. + +=head2 Grammar Definition + +The grammar is a multiple-level hash of hashes, which follows the structure of +the configuration. Each section or variable is represented by a hash with the +same structure. Each hash contains special keys starting with an underscore +such as '_sections', '_vars', '_sub' or '_re' to denote meta data with information +about that section or variable. Other keys are used to structure the hash +according to the same nesting structure of the configuration itself. The +starting hash given as parameter to 'new' contains the "root section". + +=head3 Special Section Keys + +=over 12 + +=item _sections + +Array containing the list of sub-sections of this section. Each sub-section +must then be represented by a sub-hash in this hash with the same name of the +sub-section. + +The sub-section can also be a regular expression denoted by the syntax '/re/', +where re is the regular-expression. In case a regular expression is used, a +sub-hash named with the same '/re/' must be included in this hash. + +=item _recursive + +Array containing the list of those sub-sections that are I, ie. +that can contain a new sub-section with the same syntax as themselves. + +The same effect can be accomplished with circular references in the +grammar tree or a suitable B<_dyn> section subroutine (see below}, +so this facility is included just for convenience. + +=item _vars + +Array containing the list of variables (assignments) in this section. +Analogous to sections, regular expressions can be used. + +=item _mandatory + +Array containing the list of mandatory sections and variables. + +=item _inherited + +Array containing the list of the variables that should be assigned the +same value as in the parent section if nothing is specified here. + +=item _table + +Hash containing the table grammar (see Special Table Keys). If not specified, +no table is allowed in this section. The grammar of the columns if specified +by sub-hashes named with the column number. + +=item _text + +Section contains free-form text. Only sections and @includes statements will +be interpreted, the rest will be added in the returned hash under '_text' as +string. + +B<_text> is a hash reference which can contain a B<_re> and a B<_re_error> key +which will be used to scrutanize the text ... if the hash is empty, all text +will be accepted. + +=item _order + +If defined, a '_order' element will be put in every hash containing the +sections with a number that determines the order in which the sections were +defined. + +=item _varlist + +If defined, a '_varlist' element will be put in the config hash of this +section with a list of the variables defined in the section. This can +be used to find out the order of the variable assignments. + +The '_sub' function (see below) of any variables defined in this section +will also receive a list of those variables already defined in the +same section. This can be used to enforce the order of the variables +during parsing. + +=item _doc + +Describes what this section is about + +=item _sub + +A function pointer. It is called for every instance of this section, +with the real name of the section passed as its first argument. This is +probably only useful for the regexp sections. If the function returns +a defined value it is assumed that the test was not successful and an +error is generated with the returned string as content. + +=item _dyn + +A subroutine reference (function pointer) that will be called when +a new section of this syntax is encountered. The subroutine will get +three arguments: the syntax of the section name (string or regexp), the +actual name encountered (this will be the same as the first argument for +non-regexp sections) and a reference to the grammar tree of the section. +This subroutine can then modify the grammar tree dynamically. + +=item _dyndoc + +A hash reference that lists interesting names for the section that +should be documented. The keys of the hash are the names and the +values in the hash are strings that can contain an explanation +for the name. The _dyn() subroutine is then called for each of +these names and the differences of the resulting grammar and +the original one are documented. This module can currently document +differences in the _vars list, listing new variables and removed +ones, and differences in the _sections list, listing the +new and removed sections. + +=back + +=head3 Special Variable Keys + +=over 12 + +=item _re + +Regular expression upon which the value will be checked. + +=item _re_error + +String containing the returned error in case the regular expression doesn't +match (if not specified, a generic 'syntax error' message will be returned). + +=item _sub + +A function pointer. It called for every value, with the value passed as its +first argument. If the function returns a defined value it is assumed that +the test was not successful and an error is generated with the returned +string as content. + +If the '_varlist' key (see above) is defined in this section, the '_sub' +function will also receive an array reference as the second argument. The +array contains a list of those variables already defined in the same +section. This can be used to enforce the order of the variables. + +=item _default + +A default value that will be assigned to the variable if none is specified or inherited. + +=item _doc + +Description of the variable. + +=item _example + +A one line example for the content of this variable. + +=item _dyn + +A subroutine reference (function pointer) that will be called when the +variable is assigned some value in the config file. The subroutine will +get three arguments: the name of the variable, the value assigned and +a reference to the grammar tree of this section. This subroutine can +then modify the grammar tree dynamically. + +Note that no _dyn() call is made for default and inherited values of +the variable. + +=item _dyndoc + +A hash reference that lists interesting values for the variable that +should be documented. The keys of the hash are the values and the +values in the hash are strings that can contain an explanation +for the value. The _dyn() subroutine is then called for each of +these values and the differences of the resulting grammar and +the original one are documented. This module can currently document +differences in the _vars list, listing new variables and removed +ones, and differences in the _sections list, listing the +new and removed sections. + +=back + +=head3 Special Table Keys + +=over 12 + +=item _columns + +Number of columns. If not specified, it will not be enforced. + +=item _key + +If defined, the specified column number will be used as key in a hash in the +returned hash. If not defined, the returned hash will contain a '_table' +element with the contents of the table as array. The rows of the tables are +stored as arrays. + +=item _sub + +they work analog to the description in the previous section. + +=item _doc + +describes the content of the column. + +=item _example + +example for the content of this column + +=back + +=head3 Special Text Keys + +=over 12 + +=item _re + +Regular expression upon which the text will be checked (everything as a single +line). + +=item _re_error + +String containing the returned error in case the regular expression doesn't +match (if not specified, a generic 'syntax error' message will be returned). + +=item _sub + +they work analog to the description in the previous section. + +=item _doc + +Ditto. + +=item _example + +Potential multi line example for the content of this text section + +=back + +=head2 Configuration Syntax + +=head3 General Syntax + +'#' denotes a comment up to the end-of-line, empty lines are allowed and space +at the beginning and end of lines is trimmed. + +'\' at the end of the line marks a continued line on the next line. A single +space will be inserted between the concatenated lines. + +'@include filename' is used to include another file. + +'@define a some value' will replace all occurences of 'a' in the following text +with 'some value'. + +Fields in tables that contain white space can be enclosed in either C<'> or C<">. +Whitespace can also be escaped with C<\>. Quotes inside quotes are allowed but must +be escaped with a backslash as well. + +=head3 Sections + +Config::Grammar supports hierarchical configurations through sections, whose +syntax is as follows: + +=over 15 + +=item Level 1 + +*** section name *** + +=item Level 2 + ++ section name + +=item Level 3 + +++ section name + +=item Level n, n>1 + ++..+ section name (number of '+' determines level) + +=back + +=head3 Assignments + +Assignements take the form: 'variable = value', where value can be any string +(can contain whitespaces and special characters). The spaces before and after +the equal sign are optional. + +=head3 Tabular Data + +The data is interpreted as one or more columns separated by spaces. + +=head2 Example + +=head3 Code + + my $parser = Config::Grammar->new({ + _sections => [ 'network', 'hosts' ], + network => { + _vars => [ 'dns' ], + _sections => [ "/$RE_IP/" ], + dns => { + _doc => "address of the dns server", + _example => "ns1.oetiker.xs", + _re => $RE_HOST, + _re_error => + 'dns must be an host name or ip address', + }, + "/$RE_IP/" => { + _doc => "Ip Adress", + _example => '10.2.3.2', + _vars => [ 'netmask', 'gateway' ], + netmask => { + _doc => "Netmask", + _example => "255.255.255.0", + _re => $RE_IP, + _re_error => + 'netmask must be a dotted ip address' + }, + gateway => { + _doc => "Default Gateway address in IP notation", + _example => "10.22.12.1", + _re => $RE_IP, + _re_error => + 'gateway must be a dotted ip address' }, + }, + }, + hosts => { + _doc => "Details about the hosts", + _table => { + _doc => "Description of all the Hosts", + _key => 0, + _columns => 3, + 0 => { + _doc => "Ethernet Address", + _example => "0:3:3:d:a:3:dd:a:cd", + _re => $RE_MAC, + _re_error => + 'first column must be an ethernet mac address', + }, + 1 => { + _doc => "IP Address", + _example => "10.11.23.1", + _re => $RE_IP, + _re_error => + 'second column must be a dotted ip address', + }, + 2 => { + _doc => "Host Name", + _example => "tardis", + }, + }, + }, + }); + + my $cfg = $parser->parse('test.cfg') or + die "ERROR: $parser->{err}\n"; + print Dumper($cfg); + print $praser->makepod; + +=head3 Configuration + + *** network *** + + dns = 129.132.7.87 + + + 129.132.7.64 + + netmask = 255.255.255.192 + gateway = 129.132.7.65 + + *** hosts *** + + 00:50:fe:bc:65:11 129.132.7.97 plain.hades + 00:50:fe:bc:65:12 129.132.7.98 isg.ee.hades + 00:50:fe:bc:65:14 129.132.7.99 isg.ee.hades + +=head3 Result + + { + 'hosts' => { + '00:50:fe:bc:65:11' => [ + '00:50:fe:bc:65:11', + '129.132.7.97', + 'plain.hades' + ], + '00:50:fe:bc:65:12' => [ + '00:50:fe:bc:65:12', + '129.132.7.98', + 'isg.ee.hades' + ], + '00:50:fe:bc:65:14' => [ + '00:50:fe:bc:65:14', + '129.132.7.99', + 'isg.ee.hades' + ] + }, + 'network' => { + '129.132.7.64' => { + 'netmask' => '255.255.255.192', + 'gateway' => '129.132.7.65' + }, + 'dns' => '129.132.7.87' + } + }; + +=head1 COPYRIGHT + +Copyright (c) 2000-2005 by ETH Zurich. All rights reserved. + +=head1 LICENSE + +This program is free software; you can redistribute it and/or modify it +under the same terms as Perl itself. + +=head1 AUTHOR + +David Schweikert Edws_at_ee.ethz.chE, +Tobias Oetiker Eoetiker_at_ee.ethz.chE, +Niko Tyni Entyni_at_iki.fiE + +=head1 HISTORY + + 2001-05-11 ds Initial Version of ISG::ParseConfig + 2005-03-08 ds 1.00 Renamed from ISG::ParseConfig to Config::Grammar + +=cut + +# Emacs Configuration +# +# Local Variables: +# mode: cperl +# eval: (cperl-set-style "PerlStyle") +# mode: flyspell +# mode: flyspell-prog +# End: +# +# vi: sw=4 -- cgit v1.2.3-24-g4f1b