install/deps.perl - pub/scm/infra/public-inbox - Git at Google

 # Copyright (C) all contributors <meta@public-inbox.org>
 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
 # Helper script for mass installing/uninstalling with the OS package manager
 # TODO: figure out how to handle 3rd-party repo packages for CentOS 7.x
 eval 'exec perl -S $0 ${1+"$@"}' # no shebang
 if 0; # running under some shell
 use v5.12;
 my $help = <<EOM; # make sure this fits in 80x24 terminals
 usage: $^X $0 [-f PKG_FMT] [--allow-remove] PROFILE [PROFILE_MOD]

   -f PKG_FMT      package format (`deb', `pkg', `pkg_add', `pkgin' or `rpm')
   --allow-remove  allow removing packages (DANGEROUS, non-production use only)
   --dry-run | -n  show commands that would be run
   --yes | -y      non-interactive mode / assume yes to package manager

 PROFILE is typically `www-search', `lei', or `nntpd'
 Some profile names are intended for developer use only and subject to change.
 PROFILE_MOD is only for developers checking dependencies

 OS package installation typically requires administrative privileges
 EOM
 use Getopt::Long qw(:config gnu_getopt no_ignore_case auto_abbrev);
 BEGIN { require './install/os.perl' };
 my $opt = {};
 GetOptions($opt, qw(pkg-fmt|f=s allow-remove dry-run|n yes|y help|h))
 	or die $help;
 if ($opt->{help}) { print $help; exit }
 my $pkg_fmt = $opt->{'pkg-fmt'} // do {
 	my $fmt = pkg_fmt;
 	warn "# using detected --pkg-fmt=$fmt on $ID/$VERSION_ID\n";
 	$fmt;
 };
 @ARGV or die $help;
 my @test_essential = qw(Test::Simple); # we actually use Test::More

 # package profiles.  Note we specify packages at maximum granularity,
 # which is typically deb for most things, but rpm seems to have the
 # highest granularity for things in the Perl standard library.
 my $profiles = {
 	# the smallest possible profile for testing
 	essential => [ qw(
 		autodie
 		git
 		perl
 		Digest::SHA
 		ExtUtils::MakeMaker
 		IO::Compress
 		Text::ParseWords
 		URI
 		), @test_essential ],

 	# Everything else is optional for normal use.  Only specify
 	# the minimum to pull in dependencies here:
 	optional => [ qw(
 		Date::Parse
 		BSD::Resource
 		DBD::SQLite
 		Inline::C
 		Mail::IMAPClient
 		Net::Server
 		Parse::RecDescent
 		Plack
 		Plack::Test
 		Plack::Middleware::ReverseProxy
 		Xapian
 		curl
 		highlight.pm
 		libgit2-dev
 		libxapian-dev
 		sqlite3
 		xapian-tools
 		) ],
 		# no pkg-config, libsqlite3, libxapian, libz, etc. since
 		# they'll get pulled in lib*-dev, DBD::SQlite and
 		# Xapian(.pm)  respectively

 	# optional developer stuff
 	devtest => [ qw(
 		XML::TreePP
 		w3m
 		Plack::Test::ExternalServer
 		) ],
 };

 # only for distro-agnostic dependencies which are always true:
 my $always_deps = {
 	# we only load DBI explicitly
 	'DBD::SQLite' => [ qw(DBI libsqlite3) ],
 	'Mail::IMAPClient' => 'Parse::RecDescent',
 	'Plack::Middleware::ReverseProxy' => 'Plack',
 	'Xapian' => 'libxapian',
 	'xapian-tools' => 'libxapian',
 	'libxapian-dev' => [ qw(pkg-config libxapian) ],
 	'libgit2-dev' => 'pkg-config',
 };

 # bare minimum for v2
 $profiles->{v2essential} = [ @{$profiles->{essential}}, qw(DBD::SQLite) ];

 # for old v1 installs
 $profiles->{'www-v1'} = [ @{$profiles->{essential}}, qw(Plack) ];
 $profiles->{'www-thread'} = [ @{$profiles->{v2essential}}, qw(Plack) ];

 # common profile for PublicInbox::WWW
 $profiles->{'www-search'} = [ @{$profiles->{'www-thread'}}, qw(Xapian) ];

 # bare mininum for lei
 $profiles->{'lei-core'} = [ @{$profiles->{v2essential}}, qw(Xapian) ];
 push @{$profiles->{'lei-core'}}, 'Inline::C' if $^O ne 'linux';

 # common profile for lei:
 $profiles->{lei} = [ @{$profiles->{'lei-core'}}, qw(Mail::IMAPClient curl) ];

 $profiles->{nntpd} = [ @{$profiles->{v2essential}} ];
 $profiles->{pop3d} = [ @{$profiles->{v2essential}} ];
 $profiles->{'imapd-bare'} = [ @{$profiles->{v2essential}},
 				qw(Parse::RecDescent) ];
 $profiles->{imapd} = [ @{$profiles->{'imapd-bare'}}, qw(Xapian) ];
 $profiles->{pop3d} = [ @{$profiles->{v2essential}} ];
 $profiles->{watch} = [ @{$profiles->{v2essential}}, qw(Mail::IMAPClient) ];
 $profiles->{'watch-v1'} = [ @{$profiles->{essential}} ];
 $profiles->{'watch-maildir'} = [ @{$profiles->{v2essential}} ];

 # package names which can't be mapped automatically and explicit
 # dependencies to prevent essential package removal:
 my $non_auto = { # git and perl (+autodie) are essential
 	git => {
 		pkg => [ qw(curl p5-TimeDate git) ],
 		rpm => [ qw(curl git) ],
 		pkg_add => [ qw(curl p5-Time-TimeDate git) ],
 	},
 	perl => {
 		apk => [ qw(perl perl-utils) ],
 		pkg => 'perl5',
 		pkgin => 'perl',
 		pkg_add => [], # Perl is part of OpenBSD base
 	},
 	# optional stuff:
 	'BSD::Resource' => {
 		apk => [], # not packaged for Alpine 3.19
 	},
 	'Date::Parse' => {
 		apk => 'perl-timedate',
 		deb => 'libtimedate-perl',
 		pkg => 'p5-TimeDate',
 		rpm => 'perl-TimeDate',
 		pkg_add => 'p5-Time-TimeDate',
 	},
 	'Inline::C' => {
 		apk => [ qw(perl-inline-c perl-dev) ],
 		pkg_add => 'p5-Inline', # tested OpenBSD 7.3
 		rpm => 'perl-Inline', # for CentOS 7.x, at least
 	},
 	'DBD::SQLite' => { deb => 'libdbd-sqlite3-perl' },
 	'Plack::Middleware::ReverseProxy' => {
 		apk => [], # not packaged for Alpine 3.19.0
 	},
 	'Plack::Test' => {
 		apk => 'perl-plack',
 		deb => 'libplack-perl',
 		pkg => 'p5-Plack',
 	},
 	'Plack::Test::ExternalServer' => {
 		apk => [], # not packaged for Alpine 3.19.0
 	},
 	'Xapian' => {
 		apk => 'xapian-bindings-perl',
 		deb => 'libsearch-xapian-perl',
 		pkg => 'p5-Xapian',
 		pkg_add => 'xapian-bindings-perl',
 		rpm => [], # xapian14-bindings-perl in 3rd-party repo
 	},
 	'highlight.pm' => {
 		apk => [],
 		deb => 'libhighlight-perl',
 		pkg => [],
 		pkgin => 'p5-highlight',
 		rpm => [],
 	},

 	# `libgit2' is the project name (since git has libgit)
 	'libgit2-dev' => {
 		pkg => 'libgit2',
 		rpm => 'libgit2-devel',
 	},

 	# some distros have both sqlite 2 and 3, we've only ever used 3
 	'libsqlite3' => {
 		apk => [], # handled by apk w/ perl-dbd-sqlite
 		pkg => 'sqlite3',
 		rpm => [], # `sqlite' is not removable due to yum/systemd
 		deb => [], # libsqlite3-0, but no need to specify
 	},

 	# only one version of Xapian distros
 	'libxapian' => { # avoid .so version numbers in our deps
 		deb => [], # libxapian30 atm, but no need to specify
 		pkg => 'xapian-core',
 		pkgin => 'xapian',
 		rpm => 'xapian-core',
 	},
 	'libxapian-dev' => {
 		apk => 'xapian-core-dev',
 		pkg => 'xapian-core',
 		pkgin => 'xapian',
 		rpm => 'xapian-core-devel',
 	},
 	'pkg-config' => {
 		apk => [], # handled by apk w/ xapian-core-dev
 		pkg_add => [], # part of the OpenBSD base system
 		pkg => 'pkgconf', # pkg-config is a symlink to pkgconf
 		pkgin => 'pkg-config',
 	},
 	'sqlite3' => { # this is just the executable binary on deb
 		apk => 'sqlite',
 		rpm => [], # `sqlite' is not removable due to yum/systemd
 	},

 	# we call xapian-compact(1) in public-inbox-compact(1) and
 	# xapian-delve(1) in public-inbox-cindex(1)
 	'xapian-tools' => {
 		apk => 'xapian-core',
 		pkg => 'xapian-core',
 		pkgin => 'xapian',
 		rpm => 'xapian-core', # ???
 	},

 	# OS-specific
 	'IO::KQueue' => {
 		apk => [],
 		deb => [],
 		rpm => [],
 	},
 };

 # standard library stuff that CentOS 7.x (and presumably other RPM)
 # split out and can be removed without removing the `perl' RPM:
 for (qw(autodie Digest::SHA ExtUtils::MakeMaker IO::Compress Sys::Syslog
 		Test::Simple Text::ParseWords)) {
 	# n.b.: Compress::Raw::Zlib is pulled in by IO::Compress
 	# qw(constant Encode Getopt::Long Exporter Storable Time::HiRes)
 	# don't need to be here since it's impossible to have `perl'
 	# on CentOS 7.x without them.
 	my $rpm = $_;
 	$rpm =~ s/::/-/g;
 	$non_auto->{$_} = {
 		deb => 'perl', # libperl5.XX, but the XX varies
 		pkg => 'perl5',
 		pkg_add => [], # perl is in the OpenBSD base system
 		apk => 'perl',
 		pkgin => 'perl',
 		rpm => "perl-$rpm",
 	};
 }

 # NetBSD and OpenBSD package names are similar to FreeBSD in most cases
 if ($pkg_fmt =~ /\A(?:pkg_add|pkgin)\z/) {
 	for my $name (keys %$non_auto) {
 		my $fbsd_pkg = $non_auto->{$name}->{pkg};
 		$non_auto->{$name}->{$pkg_fmt} //= $fbsd_pkg if $fbsd_pkg;
 	}
 }

 my %inst_check = ( # subs which return true if a package is intalled
 	apk => sub { system(qw(apk info -q -e), $_[0]) == 0 },
 	deb => sub { system("dpkg -s $_[0] >/dev/null 2>&1") == 0 },
 	pkg => sub { system(qw(pkg info -q), $_[0]) == 0 },
 	pkg_add => sub { system(qw(pkg_info -q -e), "$_[0]->=0") == 0 },
 	pkgin => sub { system(qw(pkg_info -q -e), $_[0]) == 0 },
 	rpm => sub { system("rpm -qs $_[0] >/dev/null 2>&1") == 0 },
 );

 our $INST_CHECK = $inst_check{$pkg_fmt} || die <<"";
 don't know how to check install status for $pkg_fmt

 my (@pkg_install, @pkg_remove, %all);
 for my $ary (values %$profiles) {
 	my @extra;
 	for my $pkg (@$ary) {
 		my $deps = $always_deps->{$pkg} // next;
 		push @extra, list($deps);
 	}
 	push @$ary, @extra;
 	$all{$_} = \@pkg_remove for @$ary;
 }
 if ($^O =~ /\A(?:free|net|open)bsd\z/) {
 	$all{'IO::KQueue'} = \@pkg_remove;
 }
 $profiles->{all} = [ keys %all ]; # pseudo-profile for all packages

 # parse the profile list from the command-line
 my @profiles = @ARGV;
 while (defined(my $profile = shift @profiles)) {
 	if ($profile =~ s/-\z//) {
 		# like apt-get, trailing "-" means remove
 		profile2dst($profile, \@pkg_remove);
 	} else {
 		profile2dst($profile, \@pkg_install);
 	}
 }

 # fill in @pkg_install and @pkg_remove:
 while (my ($pkg, $dst_pkg_list) = each %all) {
 	push @$dst_pkg_list, list(pkg2ospkg($pkg, $pkg_fmt));
 }

 my (%add, %rm); # uniquify lists
 @pkg_install = grep { !$add{$_}++ && !$INST_CHECK->($_) } @pkg_install;
 @pkg_remove = $opt->{'allow-remove'} ? grep {
 		!$add{$_} && !$rm{$_}++ && $INST_CHECK->($_)
 	} @pkg_remove : ();

 (@pkg_remove || @pkg_install) or warn "# no packages to install nor remove\n";

 # OS-specific cleanups appreciated
 if ($pkg_fmt eq 'apk') {
 	root('apk', 'add', @pkg_install) if @pkg_install;
 	root('apk', 'del', @pkg_remove) if @pkg_remove;
 } elsif ($pkg_fmt eq 'deb') {
 	my @apt_opt = qw(-o APT::Install-Recommends=false
 			-o APT::Install-Suggests=false);
 	push @apt_opt, '-y' if $opt->{yes};
 	root('apt-get', @apt_opt, qw(install),
 		@pkg_install,
 		# apt-get lets you suffix a package with "-" to
 		# remove it in an "install" sub-command:
 		map { "$_-" } @pkg_remove) if (@pkg_remove || @pkg_install);
 	root('apt-get', @apt_opt, qw(autoremove)) if $opt->{'allow-remove'};
 } elsif ($pkg_fmt eq 'pkg') { # FreeBSD
 	my @pkg_opt = $opt->{yes} ? qw(-y) : ();

 	# don't remove stuff that isn't installed:
 	root(qw(pkg remove), @pkg_opt, @pkg_remove) if @pkg_remove;
 	root(qw(pkg install), @pkg_opt, @pkg_install) if @pkg_install;
 	root(qw(pkg autoremove), @pkg_opt) if $opt->{'allow-remove'};
 } elsif ($pkg_fmt eq 'pkgin') { # NetBSD
 	my @pkg_opt = $opt->{yes} ? qw(-y) : ();
 	root(qw(pkgin), @pkg_opt, 'remove', @pkg_remove) if @pkg_remove;
 	root(qw(pkgin), @pkg_opt, 'install', @pkg_install) if @pkg_install;
 	root(qw(pkgin), @pkg_opt, 'autoremove') if $opt->{'allow-remove'};
 # TODO: yum / rpm support
 } elsif ($pkg_fmt eq 'rpm') {
 	my @pkg_opt = $opt->{yes} ? qw(-y) : ();
 	root(qw(yum remove), @pkg_opt, @pkg_remove) if @pkg_remove;
 	root(qw(yum install), @pkg_opt, @pkg_install) if @pkg_install;
 } elsif ($pkg_fmt eq 'pkg_add') { # OpenBSD
 	my @pkg_opt = $opt->{yes} ? qw(-I) : (); # -I means non-interactive
 	root(qw(pkg_delete), @pkg_opt, @pkg_remove) if @pkg_remove;
 	@pkg_install = map { "$_--" } @pkg_install; # disambiguate w3m
 	root(qw(pkg_add), @pkg_opt, @pkg_install) if @pkg_install;
 	root(qw(pkg_delete -a), @pkg_opt) if $opt->{'allow-remove'};
 } else {
 	die "unsupported package format: $pkg_fmt\n";
 }
 exit 0;


 # map a generic package name to an OS package name
 sub pkg2ospkg {
 	my ($pkg, $fmt) = @_;

 	# check explicit overrides, first:
 	if (my $ospkg = $non_auto->{$pkg}->{$fmt}) {
 		return $ospkg;
 	}

 	# check common Perl module name patterns:
 	if ($pkg =~ /::/ || $pkg =~ /\A[A-Z]/) {
 		if ($fmt eq 'apk') {
 			$pkg =~ s/::/-/g;
 			return "perl-\L$pkg"
 		} elsif ($fmt eq 'deb') {
 			$pkg =~ s/::/-/g;
 			return "lib\L$pkg-perl";
 		} elsif ($fmt eq 'rpm') {
 			$pkg =~ s/::/-/g;
 			return "perl-$pkg"
 		} elsif ($fmt =~ /\Apkg(?:_add|in)?\z/) {
 			$pkg =~ s/::/-/g;
 			return "p5-$pkg"
 		} else {
 			die "unsupported package format: $fmt for $pkg\n"
 		}
 	}

 	# use package name as-is (e.g. 'curl' or 'w3m')
 	$pkg;
 }

 # maps a install profile to a package list (@pkg_remove or @pkg_install)
 sub profile2dst {
 	my ($profile, $dst_pkg_list) = @_;
 	if (my $pkg_list = $profiles->{$profile}) {
 		$all{$_} = $dst_pkg_list for @$pkg_list;
 	} elsif ($all{$profile}) { # $profile is just a package name
 		$all{$profile} = $dst_pkg_list;
 	} else {
 		die "unrecognized profile or package: $profile\n";
 	}
 }

 sub root {
 	warn "# @_\n";
 	return if $opt->{'dry-run'};
 	return if system(@_) == 0;
 	warn "E: command failed: @_\n";
 	exit($? >> 8);
 }

 # ensure result can be pushed into an array:
 sub list {
 	my ($pkg) = @_;
 	ref($pkg) eq 'ARRAY' ? @$pkg : $pkg;
 }
	# Copyright (C) all contributors <meta@public-inbox.org>
	# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
	# Helper script for mass installing/uninstalling with the OS package manager
	# TODO: figure out how to handle 3rd-party repo packages for CentOS 7.x
	eval 'exec perl -S $0 ${1+"$@"}' # no shebang
	if 0; # running under some shell
	use v5.12;
	my $help = <<EOM; # make sure this fits in 80x24 terminals
	usage: $^X $0 [-f PKG_FMT] [--allow-remove] PROFILE [PROFILE_MOD]

	-f PKG_FMT package format (`deb', `pkg', `pkg_add', `pkgin' or `rpm')
	--allow-remove allow removing packages (DANGEROUS, non-production use only)
	--dry-run \| -n show commands that would be run
	--yes \| -y non-interactive mode / assume yes to package manager

	PROFILE is typically `www-search', `lei', or `nntpd'
	Some profile names are intended for developer use only and subject to change.
	PROFILE_MOD is only for developers checking dependencies

	OS package installation typically requires administrative privileges
	EOM
	use Getopt::Long qw(:config gnu_getopt no_ignore_case auto_abbrev);
	BEGIN { require './install/os.perl' };
	my $opt = {};
	GetOptions($opt, qw(pkg-fmt\|f=s allow-remove dry-run\|n yes\|y help\|h))
	or die $help;
	if ($opt->{help}) { print $help; exit }
	my $pkg_fmt = $opt->{'pkg-fmt'} // do {
	my $fmt = pkg_fmt;
	warn "# using detected --pkg-fmt=$fmt on $ID/$VERSION_ID\n";
	$fmt;
	};
	@ARGV or die $help;
	my @test_essential = qw(Test::Simple); # we actually use Test::More

	# package profiles. Note we specify packages at maximum granularity,
	# which is typically deb for most things, but rpm seems to have the
	# highest granularity for things in the Perl standard library.
	my $profiles = {
	# the smallest possible profile for testing
	essential => [ qw(
	autodie
	git
	perl
	Digest::SHA
	ExtUtils::MakeMaker
	IO::Compress
	Text::ParseWords
	URI
	), @test_essential ],

	# Everything else is optional for normal use. Only specify
	# the minimum to pull in dependencies here:
	optional => [ qw(
	Date::Parse
	BSD::Resource
	DBD::SQLite
	Inline::C
	Mail::IMAPClient
	Net::Server
	Parse::RecDescent
	Plack
	Plack::Test
	Plack::Middleware::ReverseProxy
	Xapian
	curl
	highlight.pm
	libgit2-dev
	libxapian-dev
	sqlite3
	xapian-tools
	) ],
	# no pkg-config, libsqlite3, libxapian, libz, etc. since
	# they'll get pulled in lib*-dev, DBD::SQlite and
	# Xapian(.pm) respectively

	# optional developer stuff
	devtest => [ qw(
	XML::TreePP
	w3m
	Plack::Test::ExternalServer
	) ],
	};

	# only for distro-agnostic dependencies which are always true:
	my $always_deps = {
	# we only load DBI explicitly
	'DBD::SQLite' => [ qw(DBI libsqlite3) ],
	'Mail::IMAPClient' => 'Parse::RecDescent',
	'Plack::Middleware::ReverseProxy' => 'Plack',
	'Xapian' => 'libxapian',
	'xapian-tools' => 'libxapian',
	'libxapian-dev' => [ qw(pkg-config libxapian) ],
	'libgit2-dev' => 'pkg-config',
	};

	# bare minimum for v2
	$profiles->{v2essential} = [ @{$profiles->{essential}}, qw(DBD::SQLite) ];

	# for old v1 installs
	$profiles->{'www-v1'} = [ @{$profiles->{essential}}, qw(Plack) ];
	$profiles->{'www-thread'} = [ @{$profiles->{v2essential}}, qw(Plack) ];

	# common profile for PublicInbox::WWW
	$profiles->{'www-search'} = [ @{$profiles->{'www-thread'}}, qw(Xapian) ];

	# bare mininum for lei
	$profiles->{'lei-core'} = [ @{$profiles->{v2essential}}, qw(Xapian) ];
	push @{$profiles->{'lei-core'}}, 'Inline::C' if $^O ne 'linux';

	# common profile for lei:
	$profiles->{lei} = [ @{$profiles->{'lei-core'}}, qw(Mail::IMAPClient curl) ];

	$profiles->{nntpd} = [ @{$profiles->{v2essential}} ];
	$profiles->{pop3d} = [ @{$profiles->{v2essential}} ];
	$profiles->{'imapd-bare'} = [ @{$profiles->{v2essential}},
	qw(Parse::RecDescent) ];
	$profiles->{imapd} = [ @{$profiles->{'imapd-bare'}}, qw(Xapian) ];
	$profiles->{pop3d} = [ @{$profiles->{v2essential}} ];
	$profiles->{watch} = [ @{$profiles->{v2essential}}, qw(Mail::IMAPClient) ];
	$profiles->{'watch-v1'} = [ @{$profiles->{essential}} ];
	$profiles->{'watch-maildir'} = [ @{$profiles->{v2essential}} ];

	# package names which can't be mapped automatically and explicit
	# dependencies to prevent essential package removal:
	my $non_auto = { # git and perl (+autodie) are essential
	git => {
	pkg => [ qw(curl p5-TimeDate git) ],
	rpm => [ qw(curl git) ],
	pkg_add => [ qw(curl p5-Time-TimeDate git) ],
	},
	perl => {
	apk => [ qw(perl perl-utils) ],
	pkg => 'perl5',
	pkgin => 'perl',
	pkg_add => [], # Perl is part of OpenBSD base
	},
	# optional stuff:
	'BSD::Resource' => {
	apk => [], # not packaged for Alpine 3.19
	},
	'Date::Parse' => {
	apk => 'perl-timedate',
	deb => 'libtimedate-perl',
	pkg => 'p5-TimeDate',
	rpm => 'perl-TimeDate',
	pkg_add => 'p5-Time-TimeDate',
	},
	'Inline::C' => {
	apk => [ qw(perl-inline-c perl-dev) ],
	pkg_add => 'p5-Inline', # tested OpenBSD 7.3
	rpm => 'perl-Inline', # for CentOS 7.x, at least
	},
	'DBD::SQLite' => { deb => 'libdbd-sqlite3-perl' },
	'Plack::Middleware::ReverseProxy' => {
	apk => [], # not packaged for Alpine 3.19.0
	},
	'Plack::Test' => {
	apk => 'perl-plack',
	deb => 'libplack-perl',
	pkg => 'p5-Plack',
	},
	'Plack::Test::ExternalServer' => {
	apk => [], # not packaged for Alpine 3.19.0
	},
	'Xapian' => {
	apk => 'xapian-bindings-perl',
	deb => 'libsearch-xapian-perl',
	pkg => 'p5-Xapian',
	pkg_add => 'xapian-bindings-perl',
	rpm => [], # xapian14-bindings-perl in 3rd-party repo
	},
	'highlight.pm' => {
	apk => [],
	deb => 'libhighlight-perl',
	pkg => [],
	pkgin => 'p5-highlight',
	rpm => [],
	},

	# `libgit2' is the project name (since git has libgit)
	'libgit2-dev' => {
	pkg => 'libgit2',
	rpm => 'libgit2-devel',
	},

	# some distros have both sqlite 2 and 3, we've only ever used 3
	'libsqlite3' => {
	apk => [], # handled by apk w/ perl-dbd-sqlite
	pkg => 'sqlite3',
	rpm => [], # `sqlite' is not removable due to yum/systemd
	deb => [], # libsqlite3-0, but no need to specify
	},

	# only one version of Xapian distros
	'libxapian' => { # avoid .so version numbers in our deps
	deb => [], # libxapian30 atm, but no need to specify
	pkg => 'xapian-core',
	pkgin => 'xapian',
	rpm => 'xapian-core',
	},
	'libxapian-dev' => {
	apk => 'xapian-core-dev',
	pkg => 'xapian-core',
	pkgin => 'xapian',
	rpm => 'xapian-core-devel',
	},
	'pkg-config' => {
	apk => [], # handled by apk w/ xapian-core-dev
	pkg_add => [], # part of the OpenBSD base system
	pkg => 'pkgconf', # pkg-config is a symlink to pkgconf
	pkgin => 'pkg-config',
	},
	'sqlite3' => { # this is just the executable binary on deb
	apk => 'sqlite',
	rpm => [], # `sqlite' is not removable due to yum/systemd
	},

	# we call xapian-compact(1) in public-inbox-compact(1) and
	# xapian-delve(1) in public-inbox-cindex(1)
	'xapian-tools' => {
	apk => 'xapian-core',
	pkg => 'xapian-core',
	pkgin => 'xapian',
	rpm => 'xapian-core', # ???
	},

	# OS-specific
	'IO::KQueue' => {
	apk => [],
	deb => [],
	rpm => [],
	},
	};

	# standard library stuff that CentOS 7.x (and presumably other RPM)
	# split out and can be removed without removing the `perl' RPM:
	for (qw(autodie Digest::SHA ExtUtils::MakeMaker IO::Compress Sys::Syslog
	Test::Simple Text::ParseWords)) {
	# n.b.: Compress::Raw::Zlib is pulled in by IO::Compress
	# qw(constant Encode Getopt::Long Exporter Storable Time::HiRes)
	# don't need to be here since it's impossible to have `perl'
	# on CentOS 7.x without them.
	my $rpm = $_;
	$rpm =~ s/::/-/g;
	$non_auto->{$_} = {
	deb => 'perl', # libperl5.XX, but the XX varies
	pkg => 'perl5',
	pkg_add => [], # perl is in the OpenBSD base system
	apk => 'perl',
	pkgin => 'perl',
	rpm => "perl-$rpm",
	};
	}

	# NetBSD and OpenBSD package names are similar to FreeBSD in most cases
	if ($pkg_fmt =~ /\A(?:pkg_add\|pkgin)\z/) {
	for my $name (keys %$non_auto) {
	my $fbsd_pkg = $non_auto->{$name}->{pkg};
	$non_auto->{$name}->{$pkg_fmt} //= $fbsd_pkg if $fbsd_pkg;
	}
	}

	my %inst_check = ( # subs which return true if a package is intalled
	apk => sub { system(qw(apk info -q -e), $_[0]) == 0 },
	deb => sub { system("dpkg -s $_[0] >/dev/null 2>&1") == 0 },
	pkg => sub { system(qw(pkg info -q), $_[0]) == 0 },
	pkg_add => sub { system(qw(pkg_info -q -e), "$_[0]->=0") == 0 },
	pkgin => sub { system(qw(pkg_info -q -e), $_[0]) == 0 },
	rpm => sub { system("rpm -qs $_[0] >/dev/null 2>&1") == 0 },
	);

	our $INST_CHECK = $inst_check{$pkg_fmt} \|\| die <<"";
	don't know how to check install status for $pkg_fmt

	my (@pkg_install, @pkg_remove, %all);
	for my $ary (values %$profiles) {
	my @extra;
	for my $pkg (@$ary) {
	my $deps = $always_deps->{$pkg} // next;
	push @extra, list($deps);
	}
	push @$ary, @extra;
	$all{$_} = \@pkg_remove for @$ary;
	}
	if ($^O =~ /\A(?:free\|net\|open)bsd\z/) {
	$all{'IO::KQueue'} = \@pkg_remove;
	}
	$profiles->{all} = [ keys %all ]; # pseudo-profile for all packages

	# parse the profile list from the command-line
	my @profiles = @ARGV;
	while (defined(my $profile = shift @profiles)) {
	if ($profile =~ s/-\z//) {
	# like apt-get, trailing "-" means remove
	profile2dst($profile, \@pkg_remove);
	} else {
	profile2dst($profile, \@pkg_install);
	}
	}

	# fill in @pkg_install and @pkg_remove:
	while (my ($pkg, $dst_pkg_list) = each %all) {
	push @$dst_pkg_list, list(pkg2ospkg($pkg, $pkg_fmt));
	}

	my (%add, %rm); # uniquify lists
	@pkg_install = grep { !$add{$_}++ && !$INST_CHECK->($_) } @pkg_install;
	@pkg_remove = $opt->{'allow-remove'} ? grep {
	!$add{$_} && !$rm{$_}++ && $INST_CHECK->($_)
	} @pkg_remove : ();

	(@pkg_remove \|\| @pkg_install) or warn "# no packages to install nor remove\n";

	# OS-specific cleanups appreciated
	if ($pkg_fmt eq 'apk') {
	root('apk', 'add', @pkg_install) if @pkg_install;
	root('apk', 'del', @pkg_remove) if @pkg_remove;
	} elsif ($pkg_fmt eq 'deb') {
	my @apt_opt = qw(-o APT::Install-Recommends=false
	-o APT::Install-Suggests=false);
	push @apt_opt, '-y' if $opt->{yes};
	root('apt-get', @apt_opt, qw(install),
	@pkg_install,
	# apt-get lets you suffix a package with "-" to
	# remove it in an "install" sub-command:
	map { "$_-" } @pkg_remove) if (@pkg_remove \|\| @pkg_install);
	root('apt-get', @apt_opt, qw(autoremove)) if $opt->{'allow-remove'};
	} elsif ($pkg_fmt eq 'pkg') { # FreeBSD
	my @pkg_opt = $opt->{yes} ? qw(-y) : ();

	# don't remove stuff that isn't installed:
	root(qw(pkg remove), @pkg_opt, @pkg_remove) if @pkg_remove;
	root(qw(pkg install), @pkg_opt, @pkg_install) if @pkg_install;
	root(qw(pkg autoremove), @pkg_opt) if $opt->{'allow-remove'};
	} elsif ($pkg_fmt eq 'pkgin') { # NetBSD
	my @pkg_opt = $opt->{yes} ? qw(-y) : ();
	root(qw(pkgin), @pkg_opt, 'remove', @pkg_remove) if @pkg_remove;
	root(qw(pkgin), @pkg_opt, 'install', @pkg_install) if @pkg_install;
	root(qw(pkgin), @pkg_opt, 'autoremove') if $opt->{'allow-remove'};
	# TODO: yum / rpm support
	} elsif ($pkg_fmt eq 'rpm') {
	my @pkg_opt = $opt->{yes} ? qw(-y) : ();
	root(qw(yum remove), @pkg_opt, @pkg_remove) if @pkg_remove;
	root(qw(yum install), @pkg_opt, @pkg_install) if @pkg_install;
	} elsif ($pkg_fmt eq 'pkg_add') { # OpenBSD
	my @pkg_opt = $opt->{yes} ? qw(-I) : (); # -I means non-interactive
	root(qw(pkg_delete), @pkg_opt, @pkg_remove) if @pkg_remove;
	@pkg_install = map { "$_--" } @pkg_install; # disambiguate w3m
	root(qw(pkg_add), @pkg_opt, @pkg_install) if @pkg_install;
	root(qw(pkg_delete -a), @pkg_opt) if $opt->{'allow-remove'};
	} else {
	die "unsupported package format: $pkg_fmt\n";
	}
	exit 0;


	# map a generic package name to an OS package name
	sub pkg2ospkg {
	my ($pkg, $fmt) = @_;

	# check explicit overrides, first:
	if (my $ospkg = $non_auto->{$pkg}->{$fmt}) {
	return $ospkg;
	}

	# check common Perl module name patterns:
	if ($pkg =~ /::/ \|\| $pkg =~ /\A[A-Z]/) {
	if ($fmt eq 'apk') {
	$pkg =~ s/::/-/g;
	return "perl-\L$pkg"
	} elsif ($fmt eq 'deb') {
	$pkg =~ s/::/-/g;
	return "lib\L$pkg-perl";
	} elsif ($fmt eq 'rpm') {
	$pkg =~ s/::/-/g;
	return "perl-$pkg"
	} elsif ($fmt =~ /\Apkg(?:_add\|in)?\z/) {
	$pkg =~ s/::/-/g;
	return "p5-$pkg"
	} else {
	die "unsupported package format: $fmt for $pkg\n"
	}
	}

	# use package name as-is (e.g. 'curl' or 'w3m')
	$pkg;
	}

	# maps a install profile to a package list (@pkg_remove or @pkg_install)
	sub profile2dst {
	my ($profile, $dst_pkg_list) = @_;
	if (my $pkg_list = $profiles->{$profile}) {
	$all{$_} = $dst_pkg_list for @$pkg_list;
	} elsif ($all{$profile}) { # $profile is just a package name
	$all{$profile} = $dst_pkg_list;
	} else {
	die "unrecognized profile or package: $profile\n";
	}
	}

	sub root {
	warn "# @_\n";
	return if $opt->{'dry-run'};
	return if system(@_) == 0;
	warn "E: command failed: @_\n";
	exit($? >> 8);
	}

	# ensure result can be pushed into an array:
	sub list {
	my ($pkg) = @_;
	ref($pkg) eq 'ARRAY' ? @$pkg : $pkg;
	}