path: root/dh_installdeb

#!/usr/bin/perl

=head1 NAME

dh_installdeb - install files into the DEBIAN directory

=cut

use strict;
use warnings;
use Debian::Debhelper::Dh_Lib;

our $VERSION = DH_BUILTIN_VERSION;

=head1 SYNOPSIS

B<dh_installdeb> [S<I<debhelper options>>]

=head1 DESCRIPTION

B<dh_installdeb> is a debhelper program that is responsible for installing
files into the F<DEBIAN> directories in package build directories with the
correct permissions.

=head1 FILES

=over 4

=item I<package>.postinst

=item I<package>.preinst

=item I<package>.postrm

=item I<package>.prerm

These maintainer scripts are installed into the F<DEBIAN> directory.

B<dh_installdeb> will perform substitution of known tokens of
the pattern B<#TOKEN#>.  In generally, scripts will want to
include the B<#DEBHELPER#> to benefit from the shell scripts
generated by debhelper commands (including those from
B<dh_installdeb> when it processes I<package>.maintscript files)

For more information on what tokens
Inside the scripts, the token B<#DEBHELPER#> is replaced with
shell script snippets generated by other debhelper commands.

=item I<package>.triggers

=item I<package>.shlibs

These control files are installed into the F<DEBIAN> directory.

Note that I<package>.shlibs is only installed in compat level 9 and
earlier.  In compat 10, please use L<dh_makeshlibs(1)>.

=item I<package>.conffiles

Historically, this file was needed to manually mark files files as
conffiles.  However, it has become de facto obsolete since debhelper
automatically computed which files should be marked as conffiles.

In compatibility level up and including 11, this control file will be
installed into the F<DEBIAN> directory.  In compatibility level 12 and
later, the file is silently ignored.

=item I<package>.maintscript

Lines in this file correspond to L<dpkg-maintscript-helper(1)>
commands and parameters.  However, the "maint-script-parameters"
should I<not> be included as debhelper will add those automatically.

Example:

    # Correct
    rm_conffile /etc/obsolete.conf 0.2~ foo
    # INCORRECT
    rm_conffile /etc/obsolete.conf 0.2~ foo -- "$@"

In compat 10 or later, any shell metacharacters will be escaped, so
arbitrary shell code cannot be inserted here.  For example, a line
such as C<mv_conffile /etc/oldconffile /etc/newconffile> will insert
maintainer script snippets into all maintainer scripts sufficient to
move that conffile.

It was also the intention to escape shell metacharacters in previous
compat levels.  However, it did not work properly and as such it was
possible to embed arbitrary shell code in earlier compat levels.

The B<dh_installdeb> tool will do some basic validation of some of
the commands listed in this file to catch common mistakes.  The
validation is enabled as a warning since compat 10 and as a hard
error in compat 12.

=back

=head1 OPTIONS

=over 4

=item B<-D>I<TOKEN=VALUE>, B<--define> I<TOKEN=VALUE>

Define tokens to be replaced inside the maintainer scripts when
it is generated.  Please note that the limitations described in
L</Limitations in token names> also applies to tokens defined
on the command line.  Invalid token names will trigger an error.

In the simple case, this parameter will cause B<< #I<TOKEN># >>
to be replaced by I<VALUE>.  If I<VALUE> starts with a literal
I<@>-sign, then I<VALUE> is expected to point to a file
containing the actual value to insert.

An explicit declared token with this parameter will replace built-in
tokens.

Test examples to aid with the understanding:

	cat >> debian/postinst <<EOF
	#SIMPLE#
	#FILEBASED#
	EOF
	echo -n "Complex value" > some-file
    dh_installdeb --define SIMPLE=direct --define FILEBASED=@some-file

In this example, B<#SIMPLE#> will expand to B<direct> and B<#FILEBASED#>
will expand to B<Complex value>.

It is also possible to do set package-specific values for a given
token.  This is useful when B<dh_installdeb> is acting on multiple
packages that need different values for the same token.  This is
done by prefixing the token name with B<< pkg.I<package-name>. >>.

This can be used as in the following example:

	cat >> debian/foo.postinst <<EOF
	# Script for #PACKAGE#
	#TOKEN#
	EOF
	cat >> debian/bar.postinst <<EOF
	# Script for #PACKAGE#
	#TOKEN#
	EOF
	cat >> debian/baz.postinst <<EOF
	# Script for #PACKAGE#
	#TOKEN#
	EOF
    dh_installdeb -pfoo -pbar -pbaz  --define TOKEN=default --define pkg.bar.TOKEN=unique-bar-value \
      --define pkg.baz.TOKEN=unique-baz-value

In this example, B<#TOKEN#> will expand to B<default> in F<debian/foo.postinst>,
to B<unique-bar-value> in F<debian/bar.postinst> and to B<unique-baz-value>
in F<debian/baz.postinst>.

Note that the B<#pkg.*#> tokens will be visible in all scripts acted on.  E.g.
you can refer to B<#pkg.bar.TOKEN#> inside F<debian/foo.postinst> and it will
be replaced by B<unique-bar-value>.

=back

=head1 SUBSTITUTION IN MAINTAINER SCRIPTS

The B<dh_installdeb> will automatically replace the following tokens
inside a provided maintainer script (if not replaced via B<-D>/B<--define>):

=over 4

=item #DEBHELPER#

This token is by default replaced with generated shell snippets debhelper
commands.  This includes the snippets generated by
B<dh_installdeb> from I<package>.maintscript file (if present).

=item #DEB_HOST_I<NAME>#, #DEB_BUILD_I<NAME>#, #DEB_TARGET_I<NAME>#

These tokens are replaced with the respective variable from
L<dpkg-architecture(1)>.  In almost all cases, you will want
use the B<< #DEB_HOST_I<NAME> >> variant in a script to ensure
you get the right value when cross-building.

On a best effort, tokens of this pattern that do not match
a variable in L<dpkg-architecture(1)> will be left as-is.

=item #ENV.I<NAME>#

These tokens of this form will be replaced with value of the
corresponding environment variable.  If the environment
variable is unset, the token is replaced with the empty
string.

Note that there are limits on which names can be used (see
L</Limitations in token names>).

=item #PACKAGE#

This token is by default replaced the package name, which will contain
the concrete script.

=back

=head2 Limitations in token names

All tokens intended to be substituted must match the regex: #[A-Za-z0-9_.+]+#

Tokens that do not match that regex will be silently ignored if found in the
script template.  Invalid token names passed to B<-D> or B<--define> will
cause B<dh_installdeb> to reject the command with an error in most cases.

=cut

my %PROVIDED_SUBST;

init(options => {
	'define|D=s%' => \%PROVIDED_SUBST,
});

# dpkg-maintscript-helper commands with their associated dpkg pre-dependency
# versions.
my %maintscript_predeps = (
	"rm_conffile" => "",
	"mv_conffile" => "",
	"symlink_to_dir" => "",
	"dir_to_symlink" => "",
);
my %maintscript_validator = (
	"rm_conffile" => \&_validate_conffile_args,
	"mv_conffile" => \&_validate_conffile_args,
);

foreach my $package (@{$dh{DOPACKAGES}}) {
	my $tmp=tmpdir($package);

	install_dir("$tmp/DEBIAN");

	if (is_udeb($package)) {
		# For udebs, only do the postinst, and no #DEBHELPER#.
		# Udebs also support menutest and isinstallable scripts.
		foreach my $script (qw{postinst menutest isinstallable}) {
			my $f=pkgfile($package,$script);
			if ($f) {
				install_prog($f, "$tmp/DEBIAN/$script");
			}
		}

		# stop here for udebs
		next;
	}
	
	my $maintscriptfile=pkgfile($package, "maintscript");
	if ($maintscriptfile) {
		if (compat(9)) {
			foreach my $line (filedoublearray($maintscriptfile)) {
				my $cmd=$line->[0];
				error("unknown dpkg-maintscript-helper command: $cmd")
					unless exists $maintscript_predeps{$cmd};
				addsubstvar($package, "misc:Pre-Depends", "dpkg",
					">= $maintscript_predeps{$cmd}")
					if length $maintscript_predeps{$cmd};
				my $params=escape_shell(@$line);
				foreach my $script (qw{postinst preinst prerm postrm}) {
					autoscript($package, $script, "maintscript-helper",
							   "s!#PARAMS#!$params!g");
				}
			}
		} else {
			my @maintscripts = filedoublearray($maintscriptfile);
			my @params;
			foreach my $line (@maintscripts) {
				my $cmd=$line->[0];
				error("unknown dpkg-maintscript-helper command: $cmd")
					unless exists $maintscript_predeps{$cmd};
				addsubstvar($package, "misc:Pre-Depends", "dpkg",
					">= $maintscript_predeps{$cmd}")
					if length $maintscript_predeps{$cmd};
				if (my $validator = $maintscript_validator{$cmd}) {
					$validator->($package, @{$line});
				}
				push(@params, escape_shell(@{$line}) );
			}
			foreach my $script (qw{postinst preinst prerm postrm}) {
				my $subst = sub {
					my @res;
					chomp;
					for my $param (@params) {
						my $line = $_;
						$line =~ s{#PARAMS#}{$param}g;
						push(@res, $line);
					}
					$_ = join("\n", @res) . "\n";
				};
				autoscript($package, $script, "maintscript-helper", $subst);
			}
		}
	}

	# Install debian scripts.
	my $package_subst = per_package_subst($package, \%PROVIDED_SUBST);
	foreach my $script (qw{postinst preinst prerm postrm}) {
		debhelper_script_subst($package, $script, $package_subst);
	}

	# Install non-executable files
	my @non_exec_files;
	# Removed in compat 12.
	push(@non_exec_files, 'conffiles') if compat(11);
	# In compat 10, we let dh_makeshlibs handle "shlibs".
	push(@non_exec_files, 'shlibs') if compat(9);
	foreach my $file (@non_exec_files) {
		my $f=pkgfile($package,$file);
		if ($f) {
			install_file($f, "$tmp/DEBIAN/$file");
		}
	}

	install_triggers($package, $tmp);

	# Automatic conffiles registration: If it is in /etc, it is a
	# conffile.
	if ( -d "$tmp/etc") {
		complex_doit("find $tmp/etc -type f -printf '/etc/%P\n' | LC_ALL=C sort >> $tmp/DEBIAN/conffiles");
		# Anything found?
		if (-z "$tmp/DEBIAN/conffiles") {
			rm_files("$tmp/DEBIAN/conffiles");
		}
		else {
			reset_perm_and_owner(0644, "$tmp/DEBIAN/conffiles");
		}
	}
}

sub install_triggers {
	my ($package, $tmp) = @_;
	my $generated = generated_file($package, 'triggers', 0);
	my @sources = grep { -f $_ } (
		pkgfile($package, 'triggers'),
		$generated,
	);
	my $target = "$tmp/DEBIAN/triggers";
	return if not @sources;
	if (@sources > 1) {
		my $merged = "${generated}.merged";
		open(my $ofd, '>', $merged)
			or error("open ${target} failed: $!");
		for my $src (@sources) {
			open(my $ifd, '<', $src)
				or error("open ${src} failed: $!");
			print {$ofd} $_ while <$ifd>;
			close($ifd);
		}
		close($ofd)	or error("close ${merged} failed: $!");
		@sources = ($merged);
	}
	install_file($sources[0], $target);
}

sub _validate_conffile_args {
	my ($package, $cmd, @args) = @_;
	my ($current_conffile, $new_conffile, $prior_version, $owning_package, $other);
	for my $arg (@args) {
		if ($arg eq '--') {
			_maybe_error("The maintscripts file for $package includes a \"--\" for one of the ${cmd} commands, but it should not");
		}
	}
	if ($cmd eq 'rm_conffile') {
		($current_conffile, $prior_version, $owning_package, $other) = @args;
	} else {
		($current_conffile, $new_conffile, $prior_version, $owning_package, $other) = @args;
	}
	$current_conffile //= '';
	_maybe_error("The current conffile path for ${cmd} must be present and absolute, got ${current_conffile}")
		if not $current_conffile or substr($current_conffile, 0, 1) ne '/';
	_maybe_error("The new conffile path for ${cmd} must be present and absolute, got ${new_conffile}")
		if $cmd eq 'mv_conffile' and (not $new_conffile or substr($new_conffile, 0, 1) ne '/');

	_maybe_error("The version for ${cmd} ${current_conffile} is not valid, got ${prior_version}")
		if $prior_version and $prior_version !~ m{^${Debian::Debhelper::Dh_Lib::PKGVERSION_REGEX}$}o;
	_maybe_error("The owning package for ${cmd} ${current_conffile} is not valid, got ${owning_package}")
		if $owning_package and $owning_package !~ m{^${Debian::Debhelper::Dh_Lib::PKGNAME_REGEX}$}o;
	if (defined($other)) {
		warning("Too many arguments for ${cmd} ${current_conffile}");
	}
}

sub _maybe_error {
	my ($msg) = @_;
	if (compat(11)) {
		warning($msg);
	} else {
		error($msg);
	}
}

sub per_package_subst {
	my ($package, $provided_subst) = @_;
	my %vars = %{$provided_subst};
	$vars{'PACKAGE'} = $package if not exists($vars{'PACKAGE'});
	for my $var (keys(%{$provided_subst})) {
		if ($var !~ $Debian::Debhelper::Dh_Lib::MAINTSCRIPT_TOKEN_REGEX) {
			warning("User defined token ${var} does not match ${Debian::Debhelper::Dh_Lib::MAINTSCRIPT_TOKEN_REGEX}");
			error("Invalid provided token ${var}: It cannot be substituted as it does not follow the token name rules");
		}
		if ($var =~ m/^pkg[.]\Q${package}\E[.](.+)$/) {
			my $new_key = $1;
			$vars{$new_key} = $provided_subst->{$var};
		}
	}
	return \%vars;
}

=head1 SEE ALSO

L<debhelper(7)>

This program is a part of debhelper.

=head1 AUTHOR

Joey Hess <joeyh@debian.org>

=cut