linux-yocto/scripts/sphinx-pre-install

#!/usr/bin/env perl

SPDX-License-Identifier: GPL-2.0-or-later

use strict;

Copyright (c) 2017-2020 Mauro Carvalho Chehab mchehab@kernel.org

my $prefix = "./"; $prefix = "$ENV{'srctree'}/" if ($ENV{'srctree'});

my $conf = $prefix . "Documentation/conf.py"; my $requirement_file = $prefix . "Documentation/sphinx/requirements.txt"; my $virtenv_prefix = "sphinx_";

Static vars

my %missing; my $system_release; my $need = 0; my $optional = 0; my $need_symlink = 0; my $need_sphinx = 0; my $need_pip = 0; my $need_virtualenv = 0; my $rec_sphinx_upgrade = 0; my $verbose_warn_install = 1; my $install = ""; my $virtenv_dir = ""; my $python_cmd = ""; my $activate_cmd; my $min_version; my $cur_version; my $rec_version = "3.4.3"; my $latest_avail_ver;

Command line arguments

my $pdf = 1; my $virtualenv = 1; my $version_check = 0;

List of required texlive packages on Fedora and OpenSuse

my %texlive = ( 'amsfonts.sty' => 'texlive-amsfonts', 'amsmath.sty' => 'texlive-amsmath', 'amssymb.sty' => 'texlive-amsfonts', 'amsthm.sty' => 'texlive-amscls', 'anyfontsize.sty' => 'texlive-anyfontsize', 'atbegshi.sty' => 'texlive-oberdiek', 'bm.sty' => 'texlive-tools', 'capt-of.sty' => 'texlive-capt-of', 'cmap.sty' => 'texlive-cmap', 'ecrm1000.tfm' => 'texlive-ec', 'eqparbox.sty' => 'texlive-eqparbox', 'eu1enc.def' => 'texlive-euenc', 'fancybox.sty' => 'texlive-fancybox', 'fancyvrb.sty' => 'texlive-fancyvrb', 'float.sty' => 'texlive-float', 'fncychap.sty' => 'texlive-fncychap', 'footnote.sty' => 'texlive-mdwtools', 'framed.sty' => 'texlive-framed', 'luatex85.sty' => 'texlive-luatex85', 'multirow.sty' => 'texlive-multirow', 'needspace.sty' => 'texlive-needspace', 'palatino.sty' => 'texlive-psnfss', 'parskip.sty' => 'texlive-parskip', 'polyglossia.sty' => 'texlive-polyglossia', 'tabulary.sty' => 'texlive-tabulary', 'threeparttable.sty' => 'texlive-threeparttable', 'titlesec.sty' => 'texlive-titlesec', 'ucs.sty' => 'texlive-ucs', 'upquote.sty' => 'texlive-upquote', 'wrapfig.sty' => 'texlive-wrapfig', 'ctexhook.sty' => 'texlive-ctex', );

Subroutines that checks if a feature exists

sub check_missing(%) { my %map = %{$_[0]};

foreach my $prog (sort keys %missing) {
	my $is_optional = $missing{$prog};

	# At least on some LTS distros like CentOS 7, texlive doesn't
	# provide all packages we need. When such distros are
	# detected, we have to disable PDF output.
	#
	# So, we need to ignore the packages that distros would
	# need for LaTeX to work
	if ($is_optional == 2 && !$pdf) {
		$optional--;
		next;
	}

	if ($verbose_warn_install) {
		if ($is_optional) {
			print "Warning: better to also install \"$prog\".\n";
		} else {
			print "ERROR: please install \"$prog\", otherwise, build won't work.\n";
		}
	}
	if (defined($map{$prog})) {
		$install .= " " . $map{$prog};
	} else {
		$install .= " " . $prog;
	}
}

$install =~ s/^\s//;

}

sub add_package($$) { my $package = shift; my $is_optional = shift;

$missing{$package} = $is_optional;
if ($is_optional) {
	$optional++;
} else {
	$need++;
}

}

sub check_missing_file($$$) { my $files = shift; my $package = shift; my $is_optional = shift;

for (@$files) {
	return if(-e $_);
}

add_package($package, $is_optional);

}

sub findprog($) { foreach(split(/:/, $ENV{PATH})) { return "$/$[0]" if(-x "$/$[0]"); } }

sub find_python_no_venv() { my $prog = shift;

my $cur_dir = qx(pwd);
$cur_dir =~ s/\s+$//;

foreach my $dir (split(/:/, $ENV{PATH})) {
	next if ($dir =~ m,($cur_dir)/sphinx,);
	return "$dir/python3" if(-x "$dir/python3");
}
foreach my $dir (split(/:/, $ENV{PATH})) {
	next if ($dir =~ m,($cur_dir)/sphinx,);
	return "$dir/python" if(-x "$dir/python");
}
return "python";

}

sub check_program($$) { my $prog = shift; my $is_optional = shift;

return $prog if findprog($prog);

add_package($prog, $is_optional);

}

sub check_perl_module($$) { my $prog = shift; my $is_optional = shift;

my $err = system("perl -M$prog -e 1 2>/dev/null /dev/null");
return if ($err == 0);

add_package($prog, $is_optional);

}

sub check_python_module($$) { my $prog = shift; my $is_optional = shift;

return if (!$python_cmd);

my $err = system("$python_cmd -c 'import $prog' 2>/dev/null /dev/null");
return if ($err == 0);

add_package($prog, $is_optional);

}

sub check_rpm_missing($$) { my @pkgs = @{$[0]}; my $is_optional = $[1];

foreach my $prog(@pkgs) {
	my $err = system("rpm -q '$prog' 2>/dev/null >/dev/null");
	add_package($prog, $is_optional) if ($err);
}

}

sub check_pacman_missing($$) { my @pkgs = @{$[0]}; my $is_optional = $[1];

foreach my $prog(@pkgs) {
	my $err = system("pacman -Q '$prog' 2>/dev/null >/dev/null");
	add_package($prog, $is_optional) if ($err);
}

}

sub check_missing_tex($) { my $is_optional = shift; my $kpsewhich = findprog("kpsewhich");

foreach my $prog(keys %texlive) {
	my $package = $texlive{$prog};
	if (!$kpsewhich) {
		add_package($package, $is_optional);
		next;
	}
	my $file = qx($kpsewhich $prog);
	add_package($package, $is_optional) if ($file =~ /^\s*$/);
}

}

sub get_sphinx_fname() { my $fname = "sphinx-build"; return $fname if findprog($fname);

$fname = "sphinx-build-3";
if (findprog($fname)) {
	$need_symlink = 1;
	return $fname;
}

return "";

}

sub get_sphinx_version($) { my $cmd = shift; my $ver;

open IN, "$cmd --version 2>&1 |";
while (<IN>) {
	if (m/^\s*sphinx-build\s+([\d\.]+)((\+\/[\da-f]+)|(b\d+))?$/) {
		$ver=$1;
		last;
	}
	# Sphinx 1.2.x uses a different format
	if (m/^\s*Sphinx.*\s+([\d\.]+)$/) {
		$ver=$1;
		last;
	}
}
close IN;
return $ver;

}

sub check_sphinx() { open IN, $conf or die "Can't open $conf"; while () { if (m/^\sneeds_sphinx\s=\s*'"['"]/) { $min_version=$1; last; } } close IN;

die "Can't get needs_sphinx version from $conf" if (!$min_version);

$virtenv_dir = $virtenv_prefix . "latest";

my $sphinx = get_sphinx_fname();
if ($sphinx eq "") {
	$need_sphinx = 1;
	return;
}

$cur_version = get_sphinx_version($sphinx);
die "$sphinx didn't return its version" if (!$cur_version);

if ($cur_version lt $min_version) {
	printf "ERROR: Sphinx version is %s. It should be >= %s\n",
	       $cur_version, $min_version;
	$need_sphinx = 1;
	return;
}

return if ($cur_version lt $rec_version);

# On version check mode, just assume Sphinx has all mandatory deps
exit (0) if ($version_check);

}

Ancillary subroutines

sub catcheck($) { my $res = ""; $res = qx(cat $[0]) if (-r $[0]); return $res; }

sub which($) { my $file = shift; my @path = split ":", $ENV{PATH};

foreach my $dir(@path) {
	my $name = $dir.'/'.$file;
	return $name if (-x $name );
}
return undef;

}

Subroutines that check distro-specific hints

sub give_debian_hints() { my %map = ( "python-sphinx" => "python3-sphinx", "yaml" => "python3-yaml", "ensurepip" => "python3-venv", "virtualenv" => "virtualenv", "dot" => "graphviz", "convert" => "imagemagick", "Pod::Usage" => "perl-modules", "xelatex" => "texlive-xetex", "rsvg-convert" => "librsvg2-bin", );

if ($pdf) {
	check_missing_file(["/usr/share/texlive/texmf-dist/tex/latex/ctex/ctexhook.sty"],
			   "texlive-lang-chinese", 2);

	check_missing_file(["/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf"],
			   "fonts-dejavu", 2);

	check_missing_file(["/usr/share/fonts/noto-cjk/NotoSansCJK-Regular.ttc",
			    "/usr/share/fonts/opentype/noto/NotoSansCJK-Regular.ttc",
			    "/usr/share/fonts/opentype/noto/NotoSerifCJK-Regular.ttc"],
			   "fonts-noto-cjk", 2);
}

check_program("dvipng", 2) if ($pdf);
check_missing(\%map);

return if (!$need && !$optional);
printf("You should run:\n") if ($verbose_warn_install);
printf("\n\tsudo apt-get install $install\n");

}

sub give_redhat_hints() { my %map = ( "python-sphinx" => "python3-sphinx", "yaml" => "python3-pyyaml", "virtualenv" => "python3-virtualenv", "dot" => "graphviz", "convert" => "ImageMagick", "Pod::Usage" => "perl-Pod-Usage", "xelatex" => "texlive-xetex-bin", "rsvg-convert" => "librsvg2-tools", );

my @fedora26_opt_pkgs = (
	"graphviz-gd",		# Fedora 26: needed for PDF support
);

my @fedora_tex_pkgs = (
	"texlive-collection-fontsrecommended",
	"texlive-collection-latex",
	"texlive-xecjk",
	"dejavu-sans-fonts",
	"dejavu-serif-fonts",
	"dejavu-sans-mono-fonts",
);

#
# Checks valid for RHEL/CentOS version 7.x.
#
my $old = 0;
my $rel;
my $noto_sans_redhat = "google-noto-sans-cjk-ttc-fonts";
$rel = $1 if ($system_release =~ /release\s+(\d+)/);

if (!($system_release =~ /Fedora/)) {
	$map{"virtualenv"} = "python-virtualenv";

	if ($rel && $rel < 8) {
		$old = 1;
		$pdf = 0;

		printf("Note: texlive packages on RHEL/CENTOS <= 7 are incomplete. Can't support PDF output\n");
		printf("If you want to build PDF, please read:\n");
		printf("\thttps://www.systutorials.com/241660/how-to-install-tex-live-on-centos-7-linux/\n");
	}
} else {
	if ($rel && $rel < 26) {
		$old = 1;
	}
	if ($rel && $rel >= 38) {
		$noto_sans_redhat = "google-noto-sans-cjk-fonts";
	}
}
if (!$rel) {
	printf("Couldn't identify release number\n");
	$old = 1;
	$pdf = 0;
}

if ($pdf) {
	check_missing_file(["/usr/share/fonts/google-noto-cjk/NotoSansCJK-Regular.ttc",
			    "/usr/share/fonts/google-noto-sans-cjk-fonts/NotoSansCJK-Regular.ttc"],
			   $noto_sans_redhat, 2);
}

check_rpm_missing(\@fedora26_opt_pkgs, 2) if ($pdf && !$old);
check_rpm_missing(\@fedora_tex_pkgs, 2) if ($pdf);
check_missing_tex(2) if ($pdf);
check_missing(\%map);

return if (!$need && !$optional);

if (!$old) {
	# dnf, for Fedora 18+
	printf("You should run:\n") if ($verbose_warn_install);
	printf("\n\tsudo dnf install -y $install\n");
} else {
	# yum, for RHEL (and clones) or Fedora version < 18
	printf("You should run:\n") if ($verbose_warn_install);
	printf("\n\tsudo yum install -y $install\n");
}

}

sub give_opensuse_hints() { my %map = ( "python-sphinx" => "python3-sphinx", "yaml" => "python3-pyyaml", "virtualenv" => "python3-virtualenv", "dot" => "graphviz", "convert" => "ImageMagick", "Pod::Usage" => "perl-Pod-Usage", "xelatex" => "texlive-xetex-bin", );

# On Tumbleweed, this package is also named rsvg-convert
$map{"rsvg-convert"} = "rsvg-view" if (!($system_release =~ /Tumbleweed/));

my @suse_tex_pkgs = (
	"texlive-babel-english",
	"texlive-caption",
	"texlive-colortbl",
	"texlive-courier",
	"texlive-dvips",
	"texlive-helvetic",
	"texlive-makeindex",
	"texlive-metafont",
	"texlive-metapost",
	"texlive-palatino",
	"texlive-preview",
	"texlive-times",
	"texlive-zapfchan",
	"texlive-zapfding",
);

$map{"latexmk"} = "texlive-latexmk-bin";

# FIXME: add support for installing CJK fonts
#
# I tried hard, but was unable to find a way to install
# "Noto Sans CJK SC" on openSUSE

check_rpm_missing(\@suse_tex_pkgs, 2) if ($pdf);
check_missing_tex(2) if ($pdf);
check_missing(\%map);

return if (!$need && !$optional);
printf("You should run:\n") if ($verbose_warn_install);
printf("\n\tsudo zypper install --no-recommends $install\n");

}

sub give_mageia_hints() { my %map = ( "python-sphinx" => "python3-sphinx", "yaml" => "python3-yaml", "virtualenv" => "python3-virtualenv", "dot" => "graphviz", "convert" => "ImageMagick", "Pod::Usage" => "perl-Pod-Usage", "xelatex" => "texlive", "rsvg-convert" => "librsvg2", );

my @tex_pkgs = (
	"texlive-fontsextra",
);

$map{"latexmk"} = "texlive-collection-basic";

my $packager_cmd;
my $noto_sans;
if ($system_release =~ /OpenMandriva/) {
	$packager_cmd = "dnf install";
	$noto_sans = "noto-sans-cjk-fonts";
	@tex_pkgs = ( "texlive-collection-fontsextra" );
} else {
	$packager_cmd = "urpmi";
	$noto_sans = "google-noto-sans-cjk-ttc-fonts";
}


if ($pdf) {
	check_missing_file(["/usr/share/fonts/google-noto-cjk/NotoSansCJK-Regular.ttc",
			    "/usr/share/fonts/TTF/NotoSans-Regular.ttf"],
			   $noto_sans, 2);
}

check_rpm_missing(\@tex_pkgs, 2) if ($pdf);
check_missing(\%map);

return if (!$need && !$optional);
printf("You should run:\n") if ($verbose_warn_install);
printf("\n\tsudo $packager_cmd $install\n");

}

sub give_arch_linux_hints() { my %map = ( "yaml" => "python-yaml", "virtualenv" => "python-virtualenv", "dot" => "graphviz", "convert" => "imagemagick", "xelatex" => "texlive-xetex", "latexmk" => "texlive-core", "rsvg-convert" => "extra/librsvg", );

my @archlinux_tex_pkgs = (
	"texlive-core",
	"texlive-latexextra",
	"ttf-dejavu",
);
check_pacman_missing(\@archlinux_tex_pkgs, 2) if ($pdf);

if ($pdf) {
	check_missing_file(["/usr/share/fonts/noto-cjk/NotoSansCJK-Regular.ttc"],
			   "noto-fonts-cjk", 2);
}

check_missing(\%map);

return if (!$need && !$optional);
printf("You should run:\n") if ($verbose_warn_install);
printf("\n\tsudo pacman -S $install\n");

}

sub give_gentoo_hints() { my %map = ( "yaml" => "dev-python/pyyaml", "virtualenv" => "dev-python/virtualenv", "dot" => "media-gfx/graphviz", "convert" => "media-gfx/imagemagick", "xelatex" => "dev-texlive/texlive-xetex media-fonts/dejavu", "rsvg-convert" => "gnome-base/librsvg", );

check_missing_file(["/usr/share/fonts/dejavu/DejaVuSans.ttf"],
		   "media-fonts/dejavu", 2) if ($pdf);

if ($pdf) {
	check_missing_file(["/usr/share/fonts/noto-cjk/NotoSansCJKsc-Regular.otf",
			    "/usr/share/fonts/noto-cjk/NotoSerifCJK-Regular.ttc"],
			   "media-fonts/noto-cjk", 2);
}

check_missing(\%map);

return if (!$need && !$optional);

printf("You should run:\n") if ($verbose_warn_install);
printf("\n");

my $imagemagick = "media-gfx/imagemagick svg png";
my $cairo = "media-gfx/graphviz cairo pdf";
my $portage_imagemagick = "/etc/portage/package.use/imagemagick";
my $portage_cairo = "/etc/portage/package.use/graphviz";

if (qx(grep imagemagick $portage_imagemagick 2>/dev/null) eq "") {
	printf("\tsudo su -c 'echo \"$imagemagick\" > $portage_imagemagick'\n")
}
if (qx(grep graphviz $portage_cairo 2>/dev/null) eq  "") {
	printf("\tsudo su -c 'echo \"$cairo\" > $portage_cairo'\n");
}

printf("\tsudo emerge --ask $install\n");

}

sub check_distros() { # Distro-specific hints if ($system_release =~ /Red Hat Enterprise Linux/) { give_redhat_hints; return; } if ($system_release =~ /CentOS/) { give_redhat_hints; return; } if ($system_release =~ /Scientific Linux/) { give_redhat_hints; return; } if ($system_release =~ /Oracle Linux Server/) { give_redhat_hints; return; } if ($system_release =~ /Fedora/) { give_redhat_hints; return; } if ($system_release =~ /Ubuntu/) { give_debian_hints; return; } if ($system_release =~ /Debian/) { give_debian_hints; return; } if ($system_release =~ /openSUSE/) { give_opensuse_hints; return; } if ($system_release =~ /Mageia/) { give_mageia_hints; return; } if ($system_release =~ /OpenMandriva/) { give_mageia_hints; return; } if ($system_release =~ /Arch Linux/) { give_arch_linux_hints; return; } if ($system_release =~ /Gentoo/) { give_gentoo_hints; return; }

#
# Fall-back to generic hint code for other distros
# That's far from ideal, specially for LaTeX dependencies.
#
my %map = (
	"sphinx-build" => "sphinx"
);
check_missing_tex(2) if ($pdf);
check_missing(\%map);
print "I don't know distro $system_release.\n";
print "So, I can't provide you a hint with the install procedure.\n";
print "There are likely missing dependencies.\n";

}

Common dependencies

sub deactivate_help() { printf "\n If you want to exit the virtualenv, you can use:\n"; printf "\tdeactivate\n"; }

sub get_virtenv() { my $ver; my $min_activate = "$ENV{'PWD'}/${virtenv_prefix}${min_version}/bin/activate"; my @activates = glob "$ENV{'PWD'}/${virtenv_prefix}*/bin/activate";

@activates = sort {$b cmp $a} @activates;

foreach my $f (@activates) {
	next if ($f lt $min_activate);

	my $sphinx_cmd = $f;
	$sphinx_cmd =~ s/activate/sphinx-build/;
	next if (! -f $sphinx_cmd);

	my $ver = get_sphinx_version($sphinx_cmd);

	if (!$ver) {
		$f =~ s#/bin/activate##;
		print("Warning: virtual environment $f is not working.\nPython version upgrade? Remove it with:\n\n\trm -rf $f\n\n");
	}

	if ($need_sphinx && ($ver ge $min_version)) {
		return ($f, $ver);
	} elsif ($ver gt $cur_version) {
		return ($f, $ver);
	}
}
return ("", "");

}

sub recommend_sphinx_upgrade() { my $venv_ver;

# Avoid running sphinx-builds from venv if $cur_version is good
if ($cur_version && ($cur_version ge $rec_version)) {
	$latest_avail_ver = $cur_version;
	return;
}

# Get the highest version from sphinx_*/bin/sphinx-build and the
# corresponding command to activate the venv/virtenv
($activate_cmd, $venv_ver) = get_virtenv();

# Store the highest version from Sphinx existing virtualenvs
if (($activate_cmd ne "") && ($venv_ver gt $cur_version)) {
	$latest_avail_ver = $venv_ver;
} else {
	$latest_avail_ver = $cur_version if ($cur_version);
}

# As we don't know package version of Sphinx, and there's no
# virtual environments, don't check if upgrades are needed
if (!$virtualenv) {
	return if (!$latest_avail_ver);
}

# Either there are already a virtual env or a new one should be created
$need_pip = 1;

return if (!$latest_avail_ver);

# Return if the reason is due to an upgrade or not
if ($latest_avail_ver lt $rec_version) {
	$rec_sphinx_upgrade = 1;
}

return $latest_avail_ver;

}

The logic here is complex, as it have to deal with different versions:

- minimal supported version;

- minimal PDF version;

- recommended version.

It also needs to work fine with both distro's package and venv/virtualenv

sub recommend_sphinx_version($) { my $virtualenv_cmd = shift;

# Version is OK. Nothing to do.
if ($cur_version && ($cur_version ge $rec_version)) {
	return;
};

if (!$need_sphinx) {
	# sphinx-build is present and its version is >= $min_version

	#only recommend enabling a newer virtenv version if makes sense.
	if ($latest_avail_ver gt $cur_version) {
		printf "\nYou may also use the newer Sphinx version $latest_avail_ver with:\n";
		printf "\tdeactivate\n"  if ($ENV{'PWD'} =~ /${virtenv_prefix}/);
		printf "\t. $activate_cmd\n";
		deactivate_help();

		return;
	}
	return if ($latest_avail_ver ge $rec_version);
}

if (!$virtualenv) {
	# No sphinx either via package or via virtenv. As we can't
	# Compare the versions here, just return, recommending the
	# user to install it from the package distro.
	return if (!$latest_avail_ver);

	# User doesn't want a virtenv recommendation, but he already
	# installed one via virtenv with a newer version.
	# So, print commands to enable it
	if ($latest_avail_ver gt $cur_version) {
		printf "\nYou may also use the Sphinx virtualenv version $latest_avail_ver with:\n";
		printf "\tdeactivate\n"  if ($ENV{'PWD'} =~ /${virtenv_prefix}/);
		printf "\t. $activate_cmd\n";
		deactivate_help();

		return;
	}
	print "\n";
} else {
	$need++ if ($need_sphinx);
}

# Suggest newer versions if current ones are too old
if ($latest_avail_ver && $latest_avail_ver ge $min_version) {
	# If there's a good enough version, ask the user to enable it
	if ($latest_avail_ver ge $rec_version) {
		printf "\nNeed to activate Sphinx (version $latest_avail_ver) on virtualenv with:\n";
		printf "\t. $activate_cmd\n";
		deactivate_help();

		return;
	}

	# Version is above the minimal required one, but may be
	# below the recommended one. So, print warnings/notes

	if ($latest_avail_ver lt $rec_version) {
		print "Warning: It is recommended at least Sphinx version $rec_version.\n";
	}
}

# At this point, either it needs Sphinx or upgrade is recommended,
# both via pip

if ($rec_sphinx_upgrade) {
	if (!$virtualenv) {
		print "Instead of install/upgrade Python Sphinx pkg, you could use pip/pypi with:\n\n";
	} else {
		print "To upgrade Sphinx, use:\n\n";
	}
} else {
	print "\nSphinx needs to be installed either:\n1) via pip/pypi with:\n\n";
}

$python_cmd = find_python_no_venv();

printf "\t$virtualenv_cmd $virtenv_dir\n";

printf "\t. $virtenv_dir/bin/activate\n";
printf "\tpip install -r $requirement_file\n";
deactivate_help();

printf "\n2) As a package with:\n";

my $old_need = $need;
my $old_optional = $optional;
%missing = ();
$pdf = 0;
$optional = 0;
$install = "";
$verbose_warn_install = 0;

add_package("python-sphinx", 0);

check_distros();

$need = $old_need;
$optional = $old_optional;

printf "\n    Please note that Sphinx >= 3.0 will currently produce false-positive\n";
printf "   warning when the same name is used for more than one type (functions,\n";
printf "   structs, enums,...). This is known Sphinx bug. For more details, see:\n";
printf "\thttps://github.com/sphinx-doc/sphinx/pull/8313\n";

}

sub check_needs() { # Check if Sphinx is already accessible from current environment check_sphinx();

if ($system_release) {
	print "Detected OS: $system_release.\n";
} else {
	print "Unknown OS\n";
}
printf "Sphinx version: %s\n\n", $cur_version if ($cur_version);

# Check python command line, trying first python3
$python_cmd = findprog("python3");
$python_cmd = check_program("python", 0) if (!$python_cmd);

# Check the type of virtual env, depending on Python version
if ($python_cmd) {
	if ($virtualenv) {
		my $tmp = qx($python_cmd --version 2>&1);
		if ($tmp =~ m/(\d+\.)(\d+\.)/) {
			if ($1 < 3) {
				# Fail if it finds python2 (or worse)
				die "Python 3 is required to build the kernel docs\n";
			}
			if ($1 == 3 && $2 < 3) {
				# Need Python 3.3 or upper for venv
				$need_virtualenv = 1;
			}
		} else {
			die "Warning: couldn't identify $python_cmd version!";
		}
	} else {
		add_package("python-sphinx", 0);
	}
}

my $venv_ver = recommend_sphinx_upgrade();

my $virtualenv_cmd;

if ($need_pip) {
	# Set virtualenv command line, if python < 3.3
	if ($need_virtualenv) {
		$virtualenv_cmd = findprog("virtualenv-3");
		$virtualenv_cmd = findprog("virtualenv-3.5") if (!$virtualenv_cmd);
		if (!$virtualenv_cmd) {
			check_program("virtualenv", 0);
			$virtualenv_cmd = "virtualenv";
		}
	} else {
		$virtualenv_cmd = "$python_cmd -m venv";
		check_python_module("ensurepip", 0);
	}
}

# Check for needed programs/tools
check_perl_module("Pod::Usage", 0);
check_python_module("yaml", 0);
check_program("make", 0);
check_program("gcc", 0);
check_program("dot", 1);
check_program("convert", 1);

# Extra PDF files - should use 2 for is_optional
check_program("xelatex", 2) if ($pdf);
check_program("rsvg-convert", 2) if ($pdf);
check_program("latexmk", 2) if ($pdf);

# Do distro-specific checks and output distro-install commands
check_distros();

if (!$python_cmd) {
	if ($need == 1) {
		die "Can't build as $need mandatory dependency is missing";
	} elsif ($need) {
		die "Can't build as $need mandatory dependencies are missing";
	}
}

# Check if sphinx-build is called sphinx-build-3
if ($need_symlink) {
	printf "\tsudo ln -sf %s /usr/bin/sphinx-build\n\n",
	       which("sphinx-build-3");
}

recommend_sphinx_version($virtualenv_cmd);
printf "\n";

print "All optional dependencies are met.\n" if (!$optional);

if ($need == 1) {
	die "Can't build as $need mandatory dependency is missing";
} elsif ($need) {
	die "Can't build as $need mandatory dependencies are missing";
}

print "Needed package dependencies are met.\n";

}

Main

while (@ARGV) { my $arg = shift(@ARGV);

if ($arg eq "--no-virtualenv") {
	$virtualenv = 0;
} elsif ($arg eq "--no-pdf"){
	$pdf = 0;
} elsif ($arg eq "--version-check"){
	$version_check = 1;
} else {
	print "Usage:\n\t$0 <--no-virtualenv> <--no-pdf> <--version-check>\n\n";
	print "Where:\n";
	print "\t--no-virtualenv\t- Recommend installing Sphinx instead of using a virtualenv\n";
	print "\t--version-check\t- if version is compatible, don't check for missing dependencies\n";
	print "\t--no-pdf\t- don't check for dependencies required to build PDF docs\n\n";
	exit -1;
}

}

Determine the system type. There's no standard unique way that would

work with all distros with a minimal package install. So, several

methods are used here.

By default, it will use lsb_release function. If not available, it will

fail back to reading the known different places where the distro name

is stored

$system_release = qx(lsb_release -d) if which("lsb_release"); $system_release =~ s/Description:\s*// if ($system_release); $system_release = catcheck("/etc/system-release") if !$system_release; $system_release = catcheck("/etc/redhat-release") if !$system_release; $system_release = catcheck("/etc/lsb-release") if !$system_release; $system_release = catcheck("/etc/gentoo-release") if !$system_release;

This seems more common than LSB these days

if (!$system_release) { my %os_var; if (open IN, "cat /etc/os-release|") { while () { if (m/^([\w\d_]+)="?([^"]*)"?\n/) { $os_var{$1}=$2; } } $system_release = $os_var{"NAME"}; if (defined($os_var{"VERSION_ID"})) { $system_release .= " " . $os_var{"VERSION_ID"} if (defined($os_var{"VERSION_ID"})); } else { $system_release .= " " . $os_var{"VERSION"}; } } } $system_release = catcheck("/etc/issue") if !$system_release; $system_release =~ s/\s+$//;

check_needs;