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authorNiko Tyni <ntyni@iki.fi>2005-03-09 18:17:06 +0100
committerNiko Tyni <ntyni@iki.fi>2005-03-09 18:17:06 +0100
commit1eda41862b7279427ab2da51b8dd12767118bfa4 (patch)
tree5d7c277a0dc98cf9029cee51746326b2a323e716 /lib/Config
parent8acdb5d58ba10ecc1dc1d57be7fdc151515c82e0 (diff)
downloadsmokeping-1eda41862b7279427ab2da51b8dd12767118bfa4.tar.gz
smokeping-1eda41862b7279427ab2da51b8dd12767118bfa4.tar.xz
* change all ISG::ParseConfig references to its new name, Config::Grammar
Diffstat (limited to 'lib/Config')
-rw-r--r--lib/Config/Grammar.pm1502
1 files changed, 1502 insertions, 0 deletions
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($$)
+{
+ my $self = shift;
+ my $file = shift;
+
+ local *File;
+ unless ($file) { $self->{'err'} = "no filename given" ;
+ return undef;};
+
+ open(File, "$file") or do {
+ $self->{'err'} = "can't open $file: $!";
+ return undef;
+ };
+ $self->{file} = $file;
+
+ local $_;
+ my $source = '';
+ while (<File>) {
+ $source .= $_;
+ chomp;
+ s/^\s+//;
+ s/\s+$//; # trim
+ s/\s*#.*$//; # comments
+ next if $_ eq ''; # empty lines
+ while (/\\$/) {# continuation
+ s/\\$//;
+ my $n = <File>;
+ last if not defined $n;
+ chomp $n;
+ $n =~ s/^\s+//;
+ $n =~ s/\s+$//; # trim
+ $_ .= ' ' . $n;
+ }
+
+ $self->{line} = $.;
+ $self->_parse_line($_, $source) or do{ close File; return 0; };
+ $source = '';
+ }
+ close File;
+ return 1;
+}
+
+# find variables in old grammar list 'listname'
+# that aren't in the corresponding list in the new grammar
+# and list them as a POD document, possibly with a callback
+# function 'docfunc'
+
+sub _findmissing($$$;$) {
+ 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($$) {
+ my $old = shift;
+ my $new = shift;
+ my @doc;
+
+ my @vdoc;
+ @vdoc = _findmissing($old, $new, '_vars');
+ push @doc, "The following variables are not valid anymore:", "=over" , @vdoc, "=back"
+ if @vdoc;
+ @vdoc = _findnew($old, $new, '_vars', \&_describevar);
+ push @doc, "The following new variables are valid:", "=over" , @vdoc, "=back"
+ if @vdoc;
+ @vdoc = _findmissing($old, $new, '_sections');
+ push @doc, "The following subsections are not valid anymore:", "=over" , @vdoc, "=back"
+ if @vdoc;
+ @vdoc = _findnew($old, $new, '_sections', sub {
+ my ($tree, $sec) = @_;
+ my @tdoc;
+ _genpod($tree->{$sec}, 0, \@tdoc);
+ return @tdoc;
+ });
+ push @doc, "The following new subsections are defined:", "=over" , @vdoc, "=back"
+ if @vdoc;
+ for (@{$old->{_sections}}) {
+ next unless exists $new->{$_};
+ @vdoc = _diffgrammars($old->{$_}, $new->{$_});
+ push @doc, "Syntax changes for subsection B<$_>", "=over", @vdoc, "=back"
+ if @vdoc;
+ }
+ return @doc;
+}
+
+# describe a variable
+
+sub _describevar {
+ my $tree = shift;
+ my $var = shift;
+ my $mandatory = ( $tree->{_mandatory} and
+ grep {$_ eq $var} @{$tree->{_mandatory}} ) ?
+ " I<(mandatory setting)>" : "";
+ my @doc;
+ push @doc, "=item B<$var>".$mandatory;
+ push @doc, $tree->{$var}{_doc} if $tree->{$var}{_doc} ;
+ my $inherited = ( $tree->{_inherited} and
+ grep {$_ eq $var} @{$tree->{_inherited}});
+ push @doc, "This variable I<inherits> its value from the parent section if nothing is specified here."
+ if $inherited;
+ push @doc, "This variable I<dynamically> modifies the grammar based on its value."
+ if $tree->{$var}{_dyn};
+ push @doc, "Default value: $var = $tree->{$var}{_default}"
+ if ($tree->{$var}{_default});
+ push @doc, "Example: $var = $tree->{$var}{_example}"
+ if ($tree->{$var}{_example});
+ return @doc;
+}
+
+sub _genpod($$$);
+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<dynamically> modified based on its name."
+ if $tree->{$section}{_dyn};
+ if ($tree->{_recursive} and
+ grep {$_ eq $section} @{$tree->{_recursive}}) {
+ push @{$doc}, "This section is I<recursive>: 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<makepod> method you can generate
+documentation of the configuration file format.
+
+The B<maketmpl> 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<recursive>, 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 E<lt>dws_at_ee.ethz.chE<gt>,
+Tobias Oetiker E<lt>oetiker_at_ee.ethz.chE<gt>,
+Niko Tyni E<lt>ntyni_at_iki.fiE<gt>
+
+=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