File Coverage

blib/lib/Text/Template.pm

Criterion	Covered	Total	%
statement	305	316	96.5
branch	124	140	88.5
condition	24	25	96.0
subroutine	37	39	94.8
pod	7	13	53.8
total	497	533	93.2

# -*- perl -*-
# Text::Template.pm
#
# Fill in `templates'
#
# Copyright 2013 M. J. Dominus.
# You may copy and distribute this program under the
# same terms as Perl itself.
# If in doubt, write to [e-mail] for a license.
#

package Text::Template;
$Text::Template::VERSION = '1.60';
# ABSTRACT: Expand template text with embedded Perl

use strict;
use warnings;

require 5.008;

use base 'Exporter';

our @EXPORT_OK = qw(fill_in_file fill_in_string TTerror);
our $ERROR;

my %GLOBAL_PREPEND = ('Text::Template' => '');

sub Version {
    $Text::Template::VERSION;
}

sub _param {
    my ($k, %h) = @_;

    for my $kk ($k, "\u$k", "\U$k", "-$k", "-\u$k", "-\U$k") {
        return $h{$kk} if exists $h{$kk};
    }

    return undef;
}

sub always_prepend {
    my $pack = shift;

    my $old = $GLOBAL_PREPEND{$pack};

    $GLOBAL_PREPEND{$pack} = shift;

    $old;
}

{
    my %LEGAL_TYPE;

    BEGIN {
        %LEGAL_TYPE = map { $_ => 1 } qw(FILE FILEHANDLE STRING ARRAY);
    }

    sub new {
        my ($pack, %a) = @_;

        my $stype     = uc(_param('type', %a) || "FILE");
        my $source    = _param('source', %a);
        my $untaint   = _param('untaint', %a);
        my $prepend   = _param('prepend', %a);
        my $alt_delim = _param('delimiters', %a);
        my $broken    = _param('broken', %a);
        my $encoding  = _param('encoding', %a);

        unless (defined $source) {
            require Carp;
            Carp::croak("Usage: $ {pack}::new(TYPE => ..., SOURCE => ...)");
        }

        unless ($LEGAL_TYPE{$stype}) {
            require Carp;
            Carp::croak("Illegal value `$stype' for TYPE parameter");
        }

        my $self = {
            TYPE     => $stype,
            PREPEND  => $prepend,
            UNTAINT  => $untaint,
            BROKEN   => $broken,
            ENCODING => $encoding,
            (defined $alt_delim ? (DELIM => $alt_delim) : ())
        };

        # Under 5.005_03, if any of $stype, $prepend, $untaint, or $broken
        # are tainted, all the others become tainted too as a result of
        # sharing the expression with them.  We install $source separately
        # to prevent it from acquiring a spurious taint.
        $self->{SOURCE} = $source;

        bless $self => $pack;
        return unless $self->_acquire_data;

        $self;
    }
}

# Convert template objects of various types to type STRING,
# in which the template data is embedded in the object itself.
sub _acquire_data {
    my $self = shift;

    my $type = $self->{TYPE};

    if ($type eq 'STRING') {
        # nothing necessary
    }
    elsif ($type eq 'FILE') {
        my $data = _load_text($self->{SOURCE});
        unless (defined $data) {

            # _load_text already set $ERROR
            return undef;
        }

        if ($self->{UNTAINT} && _is_clean($self->{SOURCE})) {
            _unconditionally_untaint($data);
        }

        if (defined $self->{ENCODING}) {
            require Encode;
            $data = Encode::decode($self->{ENCODING}, $data, &Encode::FB_CROAK);
        }

        $self->{TYPE}     = 'STRING';
        $self->{FILENAME} = $self->{SOURCE};
        $self->{SOURCE}   = $data;
    }
    elsif ($type eq 'ARRAY') {
        $self->{TYPE} = 'STRING';
        $self->{SOURCE} = join '', @{ $self->{SOURCE} };
    }
    elsif ($type eq 'FILEHANDLE') {
        $self->{TYPE} = 'STRING';
        local $/;
        my $fh   = $self->{SOURCE};
        my $data = <$fh>;             # Extra assignment avoids bug in Solaris perl5.00[45].
        if ($self->{UNTAINT}) {
            _unconditionally_untaint($data);
        }
        $self->{SOURCE} = $data;
    }
    else {
        # This should have been caught long ago, so it represents a
        # drastic `can't-happen' sort of failure
        my $pack = ref $self;
        die "Can only acquire data for $pack objects of subtype STRING, but this is $type; aborting";
    }

    $self->{DATA_ACQUIRED} = 1;
}

sub source {
    my $self = shift;

    $self->_acquire_data unless $self->{DATA_ACQUIRED};

    return $self->{SOURCE};
}

sub set_source_data {
    my ($self, $newdata, $type) = @_;

    $self->{SOURCE}        = $newdata;
    $self->{DATA_ACQUIRED} = 1;
    $self->{TYPE}          = $type || 'STRING';

    1;
}

sub compile {
    my $self = shift;

    return 1 if $self->{TYPE} eq 'PREPARSED';

    return undef unless $self->_acquire_data;

    unless ($self->{TYPE} eq 'STRING') {
        my $pack = ref $self;

        # This should have been caught long ago, so it represents a
        # drastic `can't-happen' sort of failure
        die "Can only compile $pack objects of subtype STRING, but this is $self->{TYPE}; aborting";
    }

    my @tokens;
    my $delim_pats = shift() || $self->{DELIM};

    my ($t_open, $t_close) = ('{', '}');
    my $DELIM;    # Regex matches a delimiter if $delim_pats

    if (defined $delim_pats) {
        ($t_open, $t_close) = @$delim_pats;
        $DELIM = "(?:(?:\Q$t_open\E)|(?:\Q$t_close\E))";
        @tokens = split /($DELIM|\n)/, $self->{SOURCE};
    }
    else {
        @tokens = split /(\\\\(?=\\*[{}])|\\[{}]|[{}\n])/, $self->{SOURCE};
    }

    my $state  = 'TEXT';
    my $depth  = 0;
    my $lineno = 1;
    my @content;
    my $cur_item = '';
    my $prog_start;

    while (@tokens) {
        my $t = shift @tokens;

        next if $t eq '';

        if ($t eq $t_open) {    # Brace or other opening delimiter
            if ($depth == 0) {
                push @content, [ $state, $cur_item, $lineno ] if $cur_item ne '';
                $cur_item   = '';
                $state      = 'PROG';
                $prog_start = $lineno;
            }
            else {
                $cur_item .= $t;
            }
            $depth++;
        }
        elsif ($t eq $t_close) {    # Brace or other closing delimiter
            $depth--;
            if ($depth < 0) {
                $ERROR = "Unmatched close brace at line $lineno";
                return undef;
            }
            elsif ($depth == 0) {
                push @content, [ $state, $cur_item, $prog_start ] if $cur_item ne '';
                $state    = 'TEXT';
                $cur_item = '';
            }
            else {
                $cur_item .= $t;
            }
        }
        elsif (!$delim_pats && $t eq '\\\\') {    # precedes \\\..\\\{ or \\\..\\\}
            $cur_item .= '\\';
        }
        elsif (!$delim_pats && $t =~ /^\\([{}])$/) {    # Escaped (literal) brace?
            $cur_item .= $1;
        }
        elsif ($t eq "\n") {                            # Newline
            $lineno++;
            $cur_item .= $t;
        }
        else {                                          # Anything else
            $cur_item .= $t;
        }
    }

    if ($state eq 'PROG') {
        $ERROR = "End of data inside program text that began at line $prog_start";
        return undef;
    }
    elsif ($state eq 'TEXT') {
        push @content, [ $state, $cur_item, $lineno ] if $cur_item ne '';
    }
    else {
        die "Can't happen error #1";
    }

    $self->{TYPE}   = 'PREPARSED';
    $self->{SOURCE} = \@content;

    1;
}

sub prepend_text {
    my $self = shift;

    my $t = $self->{PREPEND};

    unless (defined $t) {
        $t = $GLOBAL_PREPEND{ ref $self };
        unless (defined $t) {
            $t = $GLOBAL_PREPEND{'Text::Template'};
        }
    }

    $self->{PREPEND} = $_[1] if $#_ >= 1;

    return $t;
}

sub fill_in {
    my ($fi_self, %fi_a) = @_;

    unless ($fi_self->{TYPE} eq 'PREPARSED') {
        my $delims = _param('delimiters', %fi_a);
        my @delim_arg = (defined $delims ? ($delims) : ());
        $fi_self->compile(@delim_arg)
            or return undef;
    }

    my $fi_varhash    = _param('hash',       %fi_a);
    my $fi_package    = _param('package',    %fi_a);
    my $fi_broken     = _param('broken',     %fi_a) || $fi_self->{BROKEN} || \&_default_broken;
    my $fi_broken_arg = _param('broken_arg', %fi_a) || [];
    my $fi_safe       = _param('safe',       %fi_a);
    my $fi_ofh        = _param('output',     %fi_a);
    my $fi_filename   = _param('filename',   %fi_a) || $fi_self->{FILENAME} || 'template';
    my $fi_strict     = _param('strict',     %fi_a);
    my $fi_prepend    = _param('prepend',    %fi_a);

    my $fi_eval_package;
    my $fi_scrub_package = 0;

    unless (defined $fi_prepend) {
        $fi_prepend = $fi_self->prepend_text;
    }

    if (defined $fi_safe) {
        $fi_eval_package = 'main';
    }
    elsif (defined $fi_package) {
        $fi_eval_package = $fi_package;
    }
    elsif (defined $fi_varhash) {
        $fi_eval_package  = _gensym();
        $fi_scrub_package = 1;
    }
    else {
        $fi_eval_package = caller;
    }

    my @fi_varlist;
    my $fi_install_package;

    if (defined $fi_varhash) {
        if (defined $fi_package) {
            $fi_install_package = $fi_package;
        }
        elsif (defined $fi_safe) {
            $fi_install_package = $fi_safe->root;
        }
        else {
            $fi_install_package = $fi_eval_package;    # The gensymmed one
        }
        @fi_varlist = _install_hash($fi_varhash => $fi_install_package);
        if ($fi_strict) {
            $fi_prepend = "use vars qw(@fi_varlist);$fi_prepend" if @fi_varlist;
            $fi_prepend = "use strict;$fi_prepend";
        }
    }

    if (defined $fi_package && defined $fi_safe) {
        no strict 'refs';

        # Big fat magic here: Fix it so that the user-specified package
        # is the default one available in the safe compartment.
        *{ $fi_safe->root . '::' } = \%{ $fi_package . '::' };    # LOD
    }

    my $fi_r = '';
    my $fi_item;
    foreach $fi_item (@{ $fi_self->{SOURCE} }) {
        my ($fi_type, $fi_text, $fi_lineno) = @$fi_item;
        if ($fi_type eq 'TEXT') {
            $fi_self->append_text_to_output(
                text   => $fi_text,
                handle => $fi_ofh,
                out    => \$fi_r,
                type   => $fi_type,);
        }
        elsif ($fi_type eq 'PROG') {
            no strict;

            my $fi_lcomment = "#line $fi_lineno $fi_filename";
            my $fi_progtext = "package $fi_eval_package; $fi_prepend;\n$fi_lcomment\n$fi_text;\n;";
            my $fi_res;
            my $fi_eval_err = '';

            if ($fi_safe) {
                no strict;
                no warnings;

                $fi_safe->reval(q{undef $OUT});
                $fi_res      = $fi_safe->reval($fi_progtext);
                $fi_eval_err = $@;
                my $OUT = $fi_safe->reval('$OUT');
                $fi_res = $OUT if defined $OUT;
            }
            else {
                no strict;
                no warnings;

                my $OUT;
                $fi_res      = eval $fi_progtext;
                $fi_eval_err = $@;
                $fi_res      = $OUT if defined $OUT;
            }

            # If the value of the filled-in text really was undef,
            # change it to an explicit empty string to avoid undefined
            # value warnings later.
            $fi_res = '' unless defined $fi_res;

            if ($fi_eval_err) {
                $fi_res = $fi_broken->(
                    text   => $fi_text,
                    error  => $fi_eval_err,
                    lineno => $fi_lineno,
                    arg    => $fi_broken_arg,);
                if (defined $fi_res) {
                    $fi_self->append_text_to_output(
                        text   => $fi_res,
                        handle => $fi_ofh,
                        out    => \$fi_r,
                        type   => $fi_type,);
                }
                else {
                    return $fi_r;    # Undefined means abort processing
                }
            }
            else {
                $fi_self->append_text_to_output(
                    text   => $fi_res,
                    handle => $fi_ofh,
                    out    => \$fi_r,
                    type   => $fi_type,);
            }
        }
        else {
            die "Can't happen error #2";
        }
    }

    _scrubpkg($fi_eval_package) if $fi_scrub_package;

    defined $fi_ofh ? 1 : $fi_r;
}

sub append_text_to_output {
    my ($self, %arg) = @_;

    if (defined $arg{handle}) {
        print { $arg{handle} } $arg{text};
    }
    else {
        ${ $arg{out} } .= $arg{text};
    }

    return;
}

sub fill_this_in {
    my ($pack, $text) = splice @_, 0, 2;

    my $templ = $pack->new(TYPE => 'STRING', SOURCE => $text, @_)
        or return undef;

    $templ->compile or return undef;

    my $result = $templ->fill_in(@_);

    $result;
}

sub fill_in_string {
    my $string = shift;

    my $package = _param('package', @_);

    push @_, 'package' => scalar(caller) unless defined $package;

    Text::Template->fill_this_in($string, @_);
}

sub fill_in_file {
    my $fn = shift;
    my $templ = Text::Template->new(TYPE => 'FILE', SOURCE => $fn, @_) or return undef;

    $templ->compile or return undef;

    my $text = $templ->fill_in(@_);

    $text;
}

sub _default_broken {
    my %a = @_;

    my $prog_text = $a{text};
    my $err       = $a{error};
    my $lineno    = $a{lineno};

    chomp $err;

    #  $err =~ s/\s+at .*//s;
    "Program fragment delivered error ``$err''";
}

sub _load_text {
    my $fn = shift;

    open my $fh, '<', $fn or do {
        $ERROR = "Couldn't open file $fn: $!";
        return undef;
    };

    local $/;

    <$fh>;
}

sub _is_clean {
    my $z;

    eval { ($z = join('', @_)), eval '#' . substr($z, 0, 0); 1 }    # LOD
}

sub _unconditionally_untaint {
    for (@_) {
        ($_) = /(.*)/s;
    }
}

{
    my $seqno = 0;

    sub _gensym {
        __PACKAGE__ . '::GEN' . $seqno++;
    }

    sub _scrubpkg {
        my $s = shift;

        $s =~ s/^Text::Template:://;

        no strict 'refs';

        my $hash = $Text::Template::{ $s . "::" };

        foreach my $key (keys %$hash) {
            undef $hash->{$key};
        }

        %$hash = ();

        delete $Text::Template::{ $s . "::" };
    }
}

# Given a hashful of variables (or a list of such hashes)
# install the variables into the specified package,
# overwriting whatever variables were there before.
sub _install_hash {
    my $hashlist = shift;
    my $dest     = shift;

    if (UNIVERSAL::isa($hashlist, 'HASH')) {
        $hashlist = [$hashlist];
    }

    my @varlist;

    for my $hash (@$hashlist) {
        for my $name (keys %$hash) {
            my $val = $hash->{$name};

            no strict 'refs';
            no warnings 'redefine';

            local *SYM = *{"$ {dest}::$name"};

            if (!defined $val) {
                delete ${"$ {dest}::"}{$name};
                my $match = qr/^.\Q$name\E$/;
                @varlist = grep { $_ !~ $match } @varlist;
            }
            elsif (ref $val) {
                *SYM = $val;
                push @varlist, do {
                    if    (UNIVERSAL::isa($val, 'ARRAY')) { '@' }
                    elsif (UNIVERSAL::isa($val, 'HASH'))  { '%' }
                    else                                  { '$' }
                    }
                    . $name;
            }
            else {
                *SYM = \$val;
                push @varlist, '$' . $name;
            }
        }
    }

    @varlist;
}

sub TTerror { $ERROR }

1;

__END__