atomics: Fix atomic64_{read_acquire,set_release} fallbacks
[platform/kernel/linux-rpi.git] / scripts / sphinx-pre-install
1 #!/usr/bin/env perl
2 # SPDX-License-Identifier: GPL-2.0-or-later
3 use strict;
4
5 # Copyright (c) 2017-2020 Mauro Carvalho Chehab <mchehab@kernel.org>
6 #
7
8 my $prefix = "./";
9 $prefix = "$ENV{'srctree'}/" if ($ENV{'srctree'});
10
11 my $conf = $prefix . "Documentation/conf.py";
12 my $requirement_file = $prefix . "Documentation/sphinx/requirements.txt";
13 my $virtenv_prefix = "sphinx_";
14
15 #
16 # Static vars
17 #
18
19 my %missing;
20 my $system_release;
21 my $need = 0;
22 my $optional = 0;
23 my $need_symlink = 0;
24 my $need_sphinx = 0;
25 my $need_pip = 0;
26 my $need_virtualenv = 0;
27 my $rec_sphinx_upgrade = 0;
28 my $install = "";
29 my $virtenv_dir = "";
30 my $python_cmd = "";
31 my $activate_cmd;
32 my $min_version;
33 my $cur_version;
34 my $rec_version = "1.7.9";      # PDF won't build here
35 my $min_pdf_version = "2.4.4";  # Min version where pdf builds
36 my $latest_avail_ver;
37
38 #
39 # Command line arguments
40 #
41
42 my $pdf = 1;
43 my $virtualenv = 1;
44 my $version_check = 0;
45
46 #
47 # List of required texlive packages on Fedora and OpenSuse
48 #
49
50 my %texlive = (
51         'amsfonts.sty'       => 'texlive-amsfonts',
52         'amsmath.sty'        => 'texlive-amsmath',
53         'amssymb.sty'        => 'texlive-amsfonts',
54         'amsthm.sty'         => 'texlive-amscls',
55         'anyfontsize.sty'    => 'texlive-anyfontsize',
56         'atbegshi.sty'       => 'texlive-oberdiek',
57         'bm.sty'             => 'texlive-tools',
58         'capt-of.sty'        => 'texlive-capt-of',
59         'cmap.sty'           => 'texlive-cmap',
60         'ecrm1000.tfm'       => 'texlive-ec',
61         'eqparbox.sty'       => 'texlive-eqparbox',
62         'eu1enc.def'         => 'texlive-euenc',
63         'fancybox.sty'       => 'texlive-fancybox',
64         'fancyvrb.sty'       => 'texlive-fancyvrb',
65         'float.sty'          => 'texlive-float',
66         'fncychap.sty'       => 'texlive-fncychap',
67         'footnote.sty'       => 'texlive-mdwtools',
68         'framed.sty'         => 'texlive-framed',
69         'luatex85.sty'       => 'texlive-luatex85',
70         'multirow.sty'       => 'texlive-multirow',
71         'needspace.sty'      => 'texlive-needspace',
72         'palatino.sty'       => 'texlive-psnfss',
73         'parskip.sty'        => 'texlive-parskip',
74         'polyglossia.sty'    => 'texlive-polyglossia',
75         'tabulary.sty'       => 'texlive-tabulary',
76         'threeparttable.sty' => 'texlive-threeparttable',
77         'titlesec.sty'       => 'texlive-titlesec',
78         'ucs.sty'            => 'texlive-ucs',
79         'upquote.sty'        => 'texlive-upquote',
80         'wrapfig.sty'        => 'texlive-wrapfig',
81         'ctexhook.sty'       => 'texlive-ctex',
82 );
83
84 #
85 # Subroutines that checks if a feature exists
86 #
87
88 sub check_missing(%)
89 {
90         my %map = %{$_[0]};
91
92         foreach my $prog (sort keys %missing) {
93                 my $is_optional = $missing{$prog};
94
95                 # At least on some LTS distros like CentOS 7, texlive doesn't
96                 # provide all packages we need. When such distros are
97                 # detected, we have to disable PDF output.
98                 #
99                 # So, we need to ignore the packages that distros would
100                 # need for LaTeX to work
101                 if ($is_optional == 2 && !$pdf) {
102                         $optional--;
103                         next;
104                 }
105
106                 if ($is_optional) {
107                         print "Warning: better to also install \"$prog\".\n";
108                 } else {
109                         print "ERROR: please install \"$prog\", otherwise, build won't work.\n";
110                 }
111                 if (defined($map{$prog})) {
112                         $install .= " " . $map{$prog};
113                 } else {
114                         $install .= " " . $prog;
115                 }
116         }
117
118         $install =~ s/^\s//;
119 }
120
121 sub add_package($$)
122 {
123         my $package = shift;
124         my $is_optional = shift;
125
126         $missing{$package} = $is_optional;
127         if ($is_optional) {
128                 $optional++;
129         } else {
130                 $need++;
131         }
132 }
133
134 sub check_missing_file($$$)
135 {
136         my $files = shift;
137         my $package = shift;
138         my $is_optional = shift;
139
140         for (@$files) {
141                 return if(-e $_);
142         }
143
144         add_package($package, $is_optional);
145 }
146
147 sub findprog($)
148 {
149         foreach(split(/:/, $ENV{PATH})) {
150                 return "$_/$_[0]" if(-x "$_/$_[0]");
151         }
152 }
153
154 sub find_python_no_venv()
155 {
156         my $prog = shift;
157
158         my $cur_dir = qx(pwd);
159         $cur_dir =~ s/\s+$//;
160
161         foreach my $dir (split(/:/, $ENV{PATH})) {
162                 next if ($dir =~ m,($cur_dir)/sphinx,);
163                 return "$dir/python3" if(-x "$dir/python3");
164         }
165         foreach my $dir (split(/:/, $ENV{PATH})) {
166                 next if ($dir =~ m,($cur_dir)/sphinx,);
167                 return "$dir/python" if(-x "$dir/python");
168         }
169         return "python";
170 }
171
172 sub check_program($$)
173 {
174         my $prog = shift;
175         my $is_optional = shift;
176
177         return $prog if findprog($prog);
178
179         add_package($prog, $is_optional);
180 }
181
182 sub check_perl_module($$)
183 {
184         my $prog = shift;
185         my $is_optional = shift;
186
187         my $err = system("perl -M$prog -e 1 2>/dev/null /dev/null");
188         return if ($err == 0);
189
190         add_package($prog, $is_optional);
191 }
192
193 sub check_python_module($$)
194 {
195         my $prog = shift;
196         my $is_optional = shift;
197
198         return if (!$python_cmd);
199
200         my $err = system("$python_cmd -c 'import $prog' 2>/dev/null /dev/null");
201         return if ($err == 0);
202
203         add_package($prog, $is_optional);
204 }
205
206 sub check_rpm_missing($$)
207 {
208         my @pkgs = @{$_[0]};
209         my $is_optional = $_[1];
210
211         foreach my $prog(@pkgs) {
212                 my $err = system("rpm -q '$prog' 2>/dev/null >/dev/null");
213                 add_package($prog, $is_optional) if ($err);
214         }
215 }
216
217 sub check_pacman_missing($$)
218 {
219         my @pkgs = @{$_[0]};
220         my $is_optional = $_[1];
221
222         foreach my $prog(@pkgs) {
223                 my $err = system("pacman -Q '$prog' 2>/dev/null >/dev/null");
224                 add_package($prog, $is_optional) if ($err);
225         }
226 }
227
228 sub check_missing_tex($)
229 {
230         my $is_optional = shift;
231         my $kpsewhich = findprog("kpsewhich");
232
233         foreach my $prog(keys %texlive) {
234                 my $package = $texlive{$prog};
235                 if (!$kpsewhich) {
236                         add_package($package, $is_optional);
237                         next;
238                 }
239                 my $file = qx($kpsewhich $prog);
240                 add_package($package, $is_optional) if ($file =~ /^\s*$/);
241         }
242 }
243
244 sub get_sphinx_fname()
245 {
246         my $fname = "sphinx-build";
247         return $fname if findprog($fname);
248
249         $fname = "sphinx-build-3";
250         if (findprog($fname)) {
251                 $need_symlink = 1;
252                 return $fname;
253         }
254
255         return "";
256 }
257
258 sub get_sphinx_version($)
259 {
260         my $cmd = shift;
261         my $ver;
262
263         open IN, "$cmd --version 2>&1 |";
264         while (<IN>) {
265                 if (m/^\s*sphinx-build\s+([\d\.]+)((\+\/[\da-f]+)|(b\d+))?$/) {
266                         $ver=$1;
267                         last;
268                 }
269                 # Sphinx 1.2.x uses a different format
270                 if (m/^\s*Sphinx.*\s+([\d\.]+)$/) {
271                         $ver=$1;
272                         last;
273                 }
274         }
275         close IN;
276         return $ver;
277 }
278
279 sub check_sphinx()
280 {
281         my $default_version;
282
283         open IN, $conf or die "Can't open $conf";
284         while (<IN>) {
285                 if (m/^\s*needs_sphinx\s*=\s*[\'\"]([\d\.]+)[\'\"]/) {
286                         $min_version=$1;
287                         last;
288                 }
289         }
290         close IN;
291
292         die "Can't get needs_sphinx version from $conf" if (!$min_version);
293
294         open IN, $requirement_file or die "Can't open $requirement_file";
295         while (<IN>) {
296                 if (m/^\s*Sphinx\s*==\s*([\d\.]+)$/) {
297                         $default_version=$1;
298                         last;
299                 }
300         }
301         close IN;
302
303         die "Can't get default sphinx version from $requirement_file" if (!$default_version);
304
305         $virtenv_dir = $virtenv_prefix . $default_version;
306
307         my $sphinx = get_sphinx_fname();
308         if ($sphinx eq "") {
309                 $need_sphinx = 1;
310                 return;
311         }
312
313         $cur_version = get_sphinx_version($sphinx);
314         die ("$sphinx returned an error") if (!$cur_version);
315
316         die "$sphinx didn't return its version" if (!$cur_version);
317
318         if ($cur_version lt $min_version) {
319                 printf "ERROR: Sphinx version is %s. It should be >= %s (recommended >= %s)\n",
320                        $cur_version, $min_version, $default_version;
321                 $need_sphinx = 1;
322                 return;
323         }
324
325         return if ($cur_version lt $rec_version);
326
327         # On version check mode, just assume Sphinx has all mandatory deps
328         exit (0) if ($version_check);
329 }
330
331 #
332 # Ancillary subroutines
333 #
334
335 sub catcheck($)
336 {
337   my $res = "";
338   $res = qx(cat $_[0]) if (-r $_[0]);
339   return $res;
340 }
341
342 sub which($)
343 {
344         my $file = shift;
345         my @path = split ":", $ENV{PATH};
346
347         foreach my $dir(@path) {
348                 my $name = $dir.'/'.$file;
349                 return $name if (-x $name );
350         }
351         return undef;
352 }
353
354 #
355 # Subroutines that check distro-specific hints
356 #
357
358 sub give_debian_hints()
359 {
360         my %map = (
361                 "python-sphinx"         => "python3-sphinx",
362                 "sphinx_rtd_theme"      => "python3-sphinx-rtd-theme",
363                 "ensurepip"             => "python3-venv",
364                 "virtualenv"            => "virtualenv",
365                 "dot"                   => "graphviz",
366                 "convert"               => "imagemagick",
367                 "Pod::Usage"            => "perl-modules",
368                 "xelatex"               => "texlive-xetex",
369                 "rsvg-convert"          => "librsvg2-bin",
370         );
371
372         if ($pdf) {
373                 check_missing_file(["/usr/share/texlive/texmf-dist/tex/latex/ctex/ctexhook.sty"],
374                                    "texlive-lang-chinese", 2);
375
376                 check_missing_file(["/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf"],
377                                    "fonts-dejavu", 2);
378
379                 check_missing_file(["/usr/share/fonts/noto-cjk/NotoSansCJK-Regular.ttc",
380                                     "/usr/share/fonts/opentype/noto/NotoSansCJK-Regular.ttc",
381                                     "/usr/share/fonts/opentype/noto/NotoSerifCJK-Regular.ttc"],
382                                    "fonts-noto-cjk", 2);
383         }
384
385         check_program("dvipng", 2) if ($pdf);
386         check_missing(\%map);
387
388         return if (!$need && !$optional);
389         printf("You should run:\n\n\tsudo apt-get install $install\n");
390 }
391
392 sub give_redhat_hints()
393 {
394         my %map = (
395                 "python-sphinx"         => "python3-sphinx",
396                 "sphinx_rtd_theme"      => "python3-sphinx_rtd_theme",
397                 "virtualenv"            => "python3-virtualenv",
398                 "dot"                   => "graphviz",
399                 "convert"               => "ImageMagick",
400                 "Pod::Usage"            => "perl-Pod-Usage",
401                 "xelatex"               => "texlive-xetex-bin",
402                 "rsvg-convert"          => "librsvg2-tools",
403         );
404
405         my @fedora26_opt_pkgs = (
406                 "graphviz-gd",          # Fedora 26: needed for PDF support
407         );
408
409         my @fedora_tex_pkgs = (
410                 "texlive-collection-fontsrecommended",
411                 "texlive-collection-latex",
412                 "texlive-xecjk",
413                 "dejavu-sans-fonts",
414                 "dejavu-serif-fonts",
415                 "dejavu-sans-mono-fonts",
416         );
417
418         #
419         # Checks valid for RHEL/CentOS version 7.x.
420         #
421         my $old = 0;
422         my $rel;
423         $rel = $1 if ($system_release =~ /release\s+(\d+)/);
424
425         if (!($system_release =~ /Fedora/)) {
426                 $map{"virtualenv"} = "python-virtualenv";
427
428                 if ($rel && $rel < 8) {
429                         $old = 1;
430                         $pdf = 0;
431
432                         printf("Note: texlive packages on RHEL/CENTOS <= 7 are incomplete. Can't support PDF output\n");
433                         printf("If you want to build PDF, please read:\n");
434                         printf("\thttps://www.systutorials.com/241660/how-to-install-tex-live-on-centos-7-linux/\n");
435                 }
436         } else {
437                 if ($rel && $rel < 26) {
438                         $old = 1;
439                 }
440         }
441         if (!$rel) {
442                 printf("Couldn't identify release number\n");
443                 $old = 1;
444                 $pdf = 0;
445         }
446
447         if ($pdf) {
448                 check_missing_file(["/usr/share/fonts/google-noto-cjk/NotoSansCJK-Regular.ttc"],
449                                    "google-noto-sans-cjk-ttc-fonts", 2);
450         }
451
452         check_rpm_missing(\@fedora26_opt_pkgs, 2) if ($pdf && !$old);
453         check_rpm_missing(\@fedora_tex_pkgs, 2) if ($pdf);
454         check_missing_tex(2) if ($pdf);
455         check_missing(\%map);
456
457         return if (!$need && !$optional);
458
459         if (!$old) {
460                 # dnf, for Fedora 18+
461                 printf("You should run:\n\n\tsudo dnf install -y $install\n");
462         } else {
463                 # yum, for RHEL (and clones) or Fedora version < 18
464                 printf("You should run:\n\n\tsudo yum install -y $install\n");
465         }
466 }
467
468 sub give_opensuse_hints()
469 {
470         my %map = (
471                 "python-sphinx"         => "python3-sphinx",
472                 "sphinx_rtd_theme"      => "python3-sphinx_rtd_theme",
473                 "virtualenv"            => "python3-virtualenv",
474                 "dot"                   => "graphviz",
475                 "convert"               => "ImageMagick",
476                 "Pod::Usage"            => "perl-Pod-Usage",
477                 "xelatex"               => "texlive-xetex-bin",
478         );
479
480         # On Tumbleweed, this package is also named rsvg-convert
481         $map{"rsvg-convert"} = "rsvg-view" if (!($system_release =~ /Tumbleweed/));
482
483         my @suse_tex_pkgs = (
484                 "texlive-babel-english",
485                 "texlive-caption",
486                 "texlive-colortbl",
487                 "texlive-courier",
488                 "texlive-dvips",
489                 "texlive-helvetic",
490                 "texlive-makeindex",
491                 "texlive-metafont",
492                 "texlive-metapost",
493                 "texlive-palatino",
494                 "texlive-preview",
495                 "texlive-times",
496                 "texlive-zapfchan",
497                 "texlive-zapfding",
498         );
499
500         $map{"latexmk"} = "texlive-latexmk-bin";
501
502         # FIXME: add support for installing CJK fonts
503         #
504         # I tried hard, but was unable to find a way to install
505         # "Noto Sans CJK SC" on openSUSE
506
507         check_rpm_missing(\@suse_tex_pkgs, 2) if ($pdf);
508         check_missing_tex(2) if ($pdf);
509         check_missing(\%map);
510
511         return if (!$need && !$optional);
512         printf("You should run:\n\n\tsudo zypper install --no-recommends $install\n");
513 }
514
515 sub give_mageia_hints()
516 {
517         my %map = (
518                 "python-sphinx"         => "python3-sphinx",
519                 "sphinx_rtd_theme"      => "python3-sphinx_rtd_theme",
520                 "virtualenv"            => "python3-virtualenv",
521                 "dot"                   => "graphviz",
522                 "convert"               => "ImageMagick",
523                 "Pod::Usage"            => "perl-Pod-Usage",
524                 "xelatex"               => "texlive",
525                 "rsvg-convert"          => "librsvg2",
526         );
527
528         my @tex_pkgs = (
529                 "texlive-fontsextra",
530         );
531
532         $map{"latexmk"} = "texlive-collection-basic";
533
534         my $packager_cmd;
535         my $noto_sans;
536         if ($system_release =~ /OpenMandriva/) {
537                 $packager_cmd = "dnf install";
538                 $noto_sans = "noto-sans-cjk-fonts";
539                 @tex_pkgs = ( "texlive-collection-fontsextra" );
540         } else {
541                 $packager_cmd = "urpmi";
542                 $noto_sans = "google-noto-sans-cjk-ttc-fonts";
543         }
544
545
546         if ($pdf) {
547                 check_missing_file(["/usr/share/fonts/google-noto-cjk/NotoSansCJK-Regular.ttc",
548                                     "/usr/share/fonts/TTF/NotoSans-Regular.ttf"],
549                                    $noto_sans, 2);
550         }
551
552         check_rpm_missing(\@tex_pkgs, 2) if ($pdf);
553         check_missing(\%map);
554
555         return if (!$need && !$optional);
556         printf("You should run:\n\n\tsudo $packager_cmd $install\n");
557 }
558
559 sub give_arch_linux_hints()
560 {
561         my %map = (
562                 "sphinx_rtd_theme"      => "python-sphinx_rtd_theme",
563                 "virtualenv"            => "python-virtualenv",
564                 "dot"                   => "graphviz",
565                 "convert"               => "imagemagick",
566                 "xelatex"               => "texlive-bin",
567                 "latexmk"               => "texlive-core",
568                 "rsvg-convert"          => "extra/librsvg",
569         );
570
571         my @archlinux_tex_pkgs = (
572                 "texlive-core",
573                 "texlive-latexextra",
574                 "ttf-dejavu",
575         );
576         check_pacman_missing(\@archlinux_tex_pkgs, 2) if ($pdf);
577
578         if ($pdf) {
579                 check_missing_file(["/usr/share/fonts/noto-cjk/NotoSansCJK-Regular.ttc"],
580                                    "noto-fonts-cjk", 2);
581         }
582
583         check_missing(\%map);
584
585         return if (!$need && !$optional);
586         printf("You should run:\n\n\tsudo pacman -S $install\n");
587 }
588
589 sub give_gentoo_hints()
590 {
591         my %map = (
592                 "sphinx_rtd_theme"      => "dev-python/sphinx_rtd_theme",
593                 "virtualenv"            => "dev-python/virtualenv",
594                 "dot"                   => "media-gfx/graphviz",
595                 "convert"               => "media-gfx/imagemagick",
596                 "xelatex"               => "dev-texlive/texlive-xetex media-fonts/dejavu",
597                 "rsvg-convert"          => "gnome-base/librsvg",
598         );
599
600         check_missing_file(["/usr/share/fonts/dejavu/DejaVuSans.ttf"],
601                            "media-fonts/dejavu", 2) if ($pdf);
602
603         if ($pdf) {
604                 check_missing_file(["/usr/share/fonts/noto-cjk/NotoSansCJKsc-Regular.otf",
605                                     "/usr/share/fonts/noto-cjk/NotoSerifCJK-Regular.ttc"],
606                                    "media-fonts/noto-cjk", 2);
607         }
608
609         check_missing(\%map);
610
611         return if (!$need && !$optional);
612
613         printf("You should run:\n\n");
614
615         my $imagemagick = "media-gfx/imagemagick svg png";
616         my $cairo = "media-gfx/graphviz cairo pdf";
617         my $portage_imagemagick = "/etc/portage/package.use/imagemagick";
618         my $portage_cairo = "/etc/portage/package.use/graphviz";
619
620         if (qx(grep imagemagick $portage_imagemagick 2>/dev/null) eq "") {
621                 printf("\tsudo su -c 'echo \"$imagemagick\" > $portage_imagemagick'\n")
622         }
623         if (qx(grep graphviz $portage_cairo 2>/dev/null) eq  "") {
624                 printf("\tsudo su -c 'echo \"$cairo\" > $portage_cairo'\n");
625         }
626
627         printf("\tsudo emerge --ask $install\n");
628
629 }
630
631 sub check_distros()
632 {
633         # Distro-specific hints
634         if ($system_release =~ /Red Hat Enterprise Linux/) {
635                 give_redhat_hints;
636                 return;
637         }
638         if ($system_release =~ /CentOS/) {
639                 give_redhat_hints;
640                 return;
641         }
642         if ($system_release =~ /Scientific Linux/) {
643                 give_redhat_hints;
644                 return;
645         }
646         if ($system_release =~ /Oracle Linux Server/) {
647                 give_redhat_hints;
648                 return;
649         }
650         if ($system_release =~ /Fedora/) {
651                 give_redhat_hints;
652                 return;
653         }
654         if ($system_release =~ /Ubuntu/) {
655                 give_debian_hints;
656                 return;
657         }
658         if ($system_release =~ /Debian/) {
659                 give_debian_hints;
660                 return;
661         }
662         if ($system_release =~ /openSUSE/) {
663                 give_opensuse_hints;
664                 return;
665         }
666         if ($system_release =~ /Mageia/) {
667                 give_mageia_hints;
668                 return;
669         }
670         if ($system_release =~ /OpenMandriva/) {
671                 give_mageia_hints;
672                 return;
673         }
674         if ($system_release =~ /Arch Linux/) {
675                 give_arch_linux_hints;
676                 return;
677         }
678         if ($system_release =~ /Gentoo/) {
679                 give_gentoo_hints;
680                 return;
681         }
682
683         #
684         # Fall-back to generic hint code for other distros
685         # That's far from ideal, specially for LaTeX dependencies.
686         #
687         my %map = (
688                 "sphinx-build" => "sphinx"
689         );
690         check_missing_tex(2) if ($pdf);
691         check_missing(\%map);
692         print "I don't know distro $system_release.\n";
693         print "So, I can't provide you a hint with the install procedure.\n";
694         print "There are likely missing dependencies.\n";
695 }
696
697 #
698 # Common dependencies
699 #
700
701 sub deactivate_help()
702 {
703         printf "\nIf you want to exit the virtualenv, you can use:\n";
704         printf "\tdeactivate\n";
705 }
706
707 sub get_virtenv()
708 {
709         my $ver;
710         my $min_activate = "$ENV{'PWD'}/${virtenv_prefix}${min_version}/bin/activate";
711         my @activates = glob "$ENV{'PWD'}/${virtenv_prefix}*/bin/activate";
712
713         @activates = sort {$b cmp $a} @activates;
714
715         foreach my $f (@activates) {
716                 next if ($f lt $min_activate);
717
718                 my $sphinx_cmd = $f;
719                 $sphinx_cmd =~ s/activate/sphinx-build/;
720                 next if (! -f $sphinx_cmd);
721
722                 my $ver = get_sphinx_version($sphinx_cmd);
723                 if ($need_sphinx && ($ver ge $min_version)) {
724                         return ($f, $ver);
725                 } elsif ($ver gt $cur_version) {
726                         return ($f, $ver);
727                 }
728         }
729         return ("", "");
730 }
731
732 sub recommend_sphinx_upgrade()
733 {
734         my $venv_ver;
735
736         # Avoid running sphinx-builds from venv if $cur_version is good
737         if ($cur_version && ($cur_version ge $rec_version)) {
738                 $latest_avail_ver = $cur_version;
739                 return;
740         }
741
742         # Get the highest version from sphinx_*/bin/sphinx-build and the
743         # corresponding command to activate the venv/virtenv
744         $activate_cmd = get_virtenv();
745
746         # Store the highest version from Sphinx existing virtualenvs
747         if (($activate_cmd ne "") && ($venv_ver gt $cur_version)) {
748                 $latest_avail_ver = $venv_ver;
749         } else {
750                 $latest_avail_ver = $cur_version if ($cur_version);
751         }
752
753         # As we don't know package version of Sphinx, and there's no
754         # virtual environments, don't check if upgrades are needed
755         if (!$virtualenv) {
756                 return if (!$latest_avail_ver);
757         }
758
759         # Either there are already a virtual env or a new one should be created
760         $need_pip = 1;
761
762         # Return if the reason is due to an upgrade or not
763         if ($latest_avail_ver lt $rec_version) {
764                 $rec_sphinx_upgrade = 1;
765         }
766 }
767
768 #
769 # The logic here is complex, as it have to deal with different versions:
770 #       - minimal supported version;
771 #       - minimal PDF version;
772 #       - recommended version.
773 # It also needs to work fine with both distro's package and venv/virtualenv
774 sub recommend_sphinx_version($)
775 {
776         my $virtualenv_cmd = shift;
777
778         if ($latest_avail_ver lt $min_pdf_version) {
779                 print "note: If you want pdf, you need at least Sphinx $min_pdf_version.\n";
780         }
781
782         # Version is OK. Nothing to do.
783         return if ($cur_version && ($cur_version ge $rec_version));
784
785         if (!$need_sphinx) {
786                 # sphinx-build is present and its version is >= $min_version
787
788                 #only recommend enabling a newer virtenv version if makes sense.
789                 if ($latest_avail_ver gt $cur_version) {
790                         printf "\nYou may also use the newer Sphinx version $latest_avail_ver with:\n";
791                         printf "\tdeactivate\n"  if ($ENV{'PWD'} =~ /${virtenv_prefix}/);
792                         printf "\t. $activate_cmd\n";
793                         deactivate_help();
794
795                         return;
796                 }
797                 return if ($latest_avail_ver ge $rec_version);
798         }
799
800         if (!$virtualenv) {
801                 # No sphinx either via package or via virtenv. As we can't
802                 # Compare the versions here, just return, recommending the
803                 # user to install it from the package distro.
804                 return if (!$latest_avail_ver);
805
806                 # User doesn't want a virtenv recommendation, but he already
807                 # installed one via virtenv with a newer version.
808                 # So, print commands to enable it
809                 if ($latest_avail_ver gt $cur_version) {
810                         printf "\nYou may also use the Sphinx virtualenv version $latest_avail_ver with:\n";
811                         printf "\tdeactivate\n"  if ($ENV{'PWD'} =~ /${virtenv_prefix}/);
812                         printf "\t. $activate_cmd\n";
813                         deactivate_help();
814
815                         return;
816                 }
817                 print "\n";
818         } else {
819                 $need++ if ($need_sphinx);
820         }
821
822         # Suggest newer versions if current ones are too old
823         if ($latest_avail_ver && $cur_version ge $min_version) {
824                 # If there's a good enough version, ask the user to enable it
825                 if ($latest_avail_ver ge $rec_version) {
826                         printf "\nNeed to activate Sphinx (version $latest_avail_ver) on virtualenv with:\n";
827                         printf "\t. $activate_cmd\n";
828                         deactivate_help();
829
830                         return;
831                 }
832
833                 # Version is above the minimal required one, but may be
834                 # below the recommended one. So, print warnings/notes
835
836                 if ($latest_avail_ver lt $rec_version) {
837                         print "Warning: It is recommended at least Sphinx version $rec_version.\n";
838                 }
839         }
840
841         # At this point, either it needs Sphinx or upgrade is recommended,
842         # both via pip
843
844         if ($rec_sphinx_upgrade) {
845                 if (!$virtualenv) {
846                         print "Instead of install/upgrade Python Sphinx pkg, you could use pip/pypi with:\n\n";
847                 } else {
848                         print "To upgrade Sphinx, use:\n\n";
849                 }
850         } else {
851                 print "Sphinx needs to be installed either as a package or via pip/pypi with:\n";
852         }
853
854         $python_cmd = find_python_no_venv();
855
856         printf "\t$virtualenv_cmd $virtenv_dir\n";
857
858         printf "\t. $virtenv_dir/bin/activate\n";
859         printf "\tpip install -r $requirement_file\n";
860         deactivate_help();
861 }
862
863 sub check_needs()
864 {
865         # Check if Sphinx is already accessible from current environment
866         check_sphinx();
867
868         if ($system_release) {
869                 print "Detected OS: $system_release.\n";
870         } else {
871                 print "Unknown OS\n";
872         }
873         printf "Sphinx version: %s\n\n", $cur_version if ($cur_version);
874
875         # Check python command line, trying first python3
876         $python_cmd = findprog("python3");
877         $python_cmd = check_program("python", 0) if (!$python_cmd);
878
879         # Check the type of virtual env, depending on Python version
880         if ($python_cmd) {
881                 if ($virtualenv) {
882                         my $tmp = qx($python_cmd --version 2>&1);
883                         if ($tmp =~ m/(\d+\.)(\d+\.)/) {
884                                 if ($1 < 3) {
885                                         # Fail if it finds python2 (or worse)
886                                         die "Python 3 is required to build the kernel docs\n";
887                                 }
888                                 if ($1 == 3 && $2 < 3) {
889                                         # Need Python 3.3 or upper for venv
890                                         $need_virtualenv = 1;
891                                 }
892                         } else {
893                                 die "Warning: couldn't identify $python_cmd version!";
894                         }
895                 } else {
896                         add_package("python-sphinx", 0);
897                 }
898         }
899
900         recommend_sphinx_upgrade();
901
902         my $virtualenv_cmd;
903
904         if ($need_pip) {
905                 # Set virtualenv command line, if python < 3.3
906                 if ($need_virtualenv) {
907                         $virtualenv_cmd = findprog("virtualenv-3");
908                         $virtualenv_cmd = findprog("virtualenv-3.5") if (!$virtualenv_cmd);
909                         if (!$virtualenv_cmd) {
910                                 check_program("virtualenv", 0);
911                                 $virtualenv_cmd = "virtualenv";
912                         }
913                 } else {
914                         $virtualenv_cmd = "$python_cmd -m venv";
915                         check_python_module("ensurepip", 0);
916                 }
917         }
918
919         # Check for needed programs/tools
920         check_perl_module("Pod::Usage", 0);
921         check_program("make", 0);
922         check_program("gcc", 0);
923         check_python_module("sphinx_rtd_theme", 1) if (!$virtualenv);
924         check_program("dot", 1);
925         check_program("convert", 1);
926
927         # Extra PDF files - should use 2 for is_optional
928         check_program("xelatex", 2) if ($pdf);
929         check_program("rsvg-convert", 2) if ($pdf);
930         check_program("latexmk", 2) if ($pdf);
931
932         # Do distro-specific checks and output distro-install commands
933         check_distros();
934
935         if (!$python_cmd) {
936                 if ($need == 1) {
937                         die "Can't build as $need mandatory dependency is missing";
938                 } elsif ($need) {
939                         die "Can't build as $need mandatory dependencies are missing";
940                 }
941         }
942
943         # Check if sphinx-build is called sphinx-build-3
944         if ($need_symlink) {
945                 printf "\tsudo ln -sf %s /usr/bin/sphinx-build\n\n",
946                        which("sphinx-build-3");
947         }
948
949         recommend_sphinx_version($virtualenv_cmd);
950         printf "\n";
951
952         print "All optional dependencies are met.\n" if (!$optional);
953
954         if ($need == 1) {
955                 die "Can't build as $need mandatory dependency is missing";
956         } elsif ($need) {
957                 die "Can't build as $need mandatory dependencies are missing";
958         }
959
960         print "Needed package dependencies are met.\n";
961 }
962
963 #
964 # Main
965 #
966
967 while (@ARGV) {
968         my $arg = shift(@ARGV);
969
970         if ($arg eq "--no-virtualenv") {
971                 $virtualenv = 0;
972         } elsif ($arg eq "--no-pdf"){
973                 $pdf = 0;
974         } elsif ($arg eq "--version-check"){
975                 $version_check = 1;
976         } else {
977                 print "Usage:\n\t$0 <--no-virtualenv> <--no-pdf> <--version-check>\n\n";
978                 print "Where:\n";
979                 print "\t--no-virtualenv\t- Recommend installing Sphinx instead of using a virtualenv\n";
980                 print "\t--version-check\t- if version is compatible, don't check for missing dependencies\n";
981                 print "\t--no-pdf\t- don't check for dependencies required to build PDF docs\n\n";
982                 exit -1;
983         }
984 }
985
986 #
987 # Determine the system type. There's no standard unique way that would
988 # work with all distros with a minimal package install. So, several
989 # methods are used here.
990 #
991 # By default, it will use lsb_release function. If not available, it will
992 # fail back to reading the known different places where the distro name
993 # is stored
994 #
995
996 $system_release = qx(lsb_release -d) if which("lsb_release");
997 $system_release =~ s/Description:\s*// if ($system_release);
998 $system_release = catcheck("/etc/system-release") if !$system_release;
999 $system_release = catcheck("/etc/redhat-release") if !$system_release;
1000 $system_release = catcheck("/etc/lsb-release") if !$system_release;
1001 $system_release = catcheck("/etc/gentoo-release") if !$system_release;
1002
1003 # This seems more common than LSB these days
1004 if (!$system_release) {
1005         my %os_var;
1006         if (open IN, "cat /etc/os-release|") {
1007                 while (<IN>) {
1008                         if (m/^([\w\d\_]+)=\"?([^\"]*)\"?\n/) {
1009                                 $os_var{$1}=$2;
1010                         }
1011                 }
1012                 $system_release = $os_var{"NAME"};
1013                 if (defined($os_var{"VERSION_ID"})) {
1014                         $system_release .= " " . $os_var{"VERSION_ID"} if (defined($os_var{"VERSION_ID"}));
1015                 } else {
1016                         $system_release .= " " . $os_var{"VERSION"};
1017                 }
1018         }
1019 }
1020 $system_release = catcheck("/etc/issue") if !$system_release;
1021 $system_release =~ s/\s+$//;
1022
1023 check_needs;