Improve accessibility of -T html -O toc output by using the <nav> element

in the DPUB-ARIA doc-toc role.
Patch from Anna Vyalkova <cyber at sysrq dot in> slightly tweaked by me.

This is hopefully the start of a collaboration to improve accessibility
of Unix manual pages using the WAI-ARIA, HTML-ARIA, and DPUB-ARIA standards.
Progress appears to be possible without changing *anything* with respect to
the way manual pages are written.  Instead, it seems sufficient to properly
translate semantic cues already implied by existing mdoc(7) markup into the
appropriate HTML elements and ARIA attributes.  Overall, the total length
of HTML output is likely to increase slightly, but not much.

diff --git a/usr.bin/mandoc/html.c b/usr.bin/mandoc/html.c
index 1e996da..bff2105 100644 (file)
--- a/usr.bin/mandoc/html.c
+++ b/usr.bin/mandoc/html.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: html.c,v 1.146 2021/09/09 14:45:18 schwarze Exp $ */
+/* $OpenBSD: html.c,v 1.147 2022/06/24 11:15:19 schwarze Exp $ */
 /*
  * Copyright (c) 2008-2011, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2011-2015, 2017-2021 Ingo Schwarze <schwarze@openbsd.org>
@@ -67,6 +67,7 @@ static        const struct htmldata htmltags[TAG_MAX] = {
        {"body",        HTML_NLALL},
        {"div",         HTML_NLAROUND},
        {"section",     HTML_NLALL},
+       {"nav",         HTML_NLALL},
        {"table",       HTML_NLALL | HTML_INDENT},
        {"tr",          HTML_NLALL | HTML_INDENT},
        {"td",          HTML_NLAROUND},
@@ -706,6 +707,9 @@ print_otag(struct html *h, enum htmltag tag, const char *fmt, ...)
                case 'i':
                        attr = "id";
                        break;
+               case 'r':
+                       attr = "role";
+                       break;
                case '?':
                        attr = arg1;
                        arg1 = va_arg(ap, char *);

diff --git a/usr.bin/mandoc/html.h b/usr.bin/mandoc/html.h
index 06ba51e..5ca0a38 100644 (file)
--- a/usr.bin/mandoc/html.h
+++ b/usr.bin/mandoc/html.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: html.h,v 1.71 2021/09/09 14:45:18 schwarze Exp $ */
+/* $OpenBSD: html.h,v 1.72 2022/06/24 11:15:19 schwarze Exp $ */
 /*
  * Copyright (c) 2017, 2018, 2019, 2020 Ingo Schwarze <schwarze@openbsd.org>
  * Copyright (c) 2008-2011, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
@@ -29,6 +29,7 @@ enum  htmltag {
        TAG_BODY,
        TAG_DIV,
        TAG_SECTION,
+       TAG_NAV,
        TAG_TABLE,
        TAG_TR,
        TAG_TD,

diff --git a/usr.bin/mandoc/mdoc_html.c b/usr.bin/mandoc/mdoc_html.c
index e6dbfbe..8d34d5a 100644 (file)
--- a/usr.bin/mandoc/mdoc_html.c
+++ b/usr.bin/mandoc/mdoc_html.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: mdoc_html.c,v 1.217 2021/03/30 19:23:50 schwarze Exp $ */
+/* $OpenBSD: mdoc_html.c,v 1.218 2022/06/24 11:15:19 schwarze Exp $ */
 /*
  * Copyright (c) 2014-2021 Ingo Schwarze <schwarze@openbsd.org>
  * Copyright (c) 2008-2011, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
@@ -513,7 +513,7 @@ static int
 mdoc_sh_pre(MDOC_ARGS)
 {
        struct roff_node        *sn, *subn;
-       struct tag              *t, *tsec, *tsub;
+       struct tag              *t, *tnav, *tsec, *tsub;
        char                    *id;
        int                      sc;
 
@@ -534,6 +534,7 @@ mdoc_sh_pre(MDOC_ARGS)
                                        break;
                if (sc < 2)
                        break;
+               tnav = print_otag(h, TAG_NAV, "r", "doc-toc");
                t = print_otag(h, TAG_H1, "c", "Sh");
                print_text(h, "TABLE OF CONTENTS");
                print_tagq(h, t);
@@ -565,7 +566,7 @@ mdoc_sh_pre(MDOC_ARGS)
                        }
                        print_tagq(h, tsec);
                }
-               print_tagq(h, t);
+               print_tagq(h, tnav);
                print_otag(h, TAG_SECTION, "c", "Sh");
                break;
        case ROFFT_HEAD: