[docs]: Add Russian language support (6/7).

* doc/groff.texi (Input Encodings, Manipulating Hyphenation):
* doc/ms.ms:
* man/groff_tmac.5.man (Localization packages, Input encodings):
* man/groff.7.man (Localization): Document support for KOI8-R encoding
  and Russian language.

5 files changed, 75 insertions, 7 deletions

diff --git a/ChangeLog b/ChangeLog
index 59e2159c9..f407a5229 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,15 @@
 2023-03-08  G. Branden Robinson <g.branden.robinson@gmail.com>
 
+	[docs]: Add Russian language support (6/7).
+
+	* doc/groff.texi (Input Encodings, Manipulating Hyphenation):
+	* doc/ms.ms:
+	* man/groff_tmac.5.man (Localization packages, Input encodings):
+	* man/groff.7.man (Localization): Document support for KOI8-R
+	encoding and Russian language.
+
+2023-03-08  G. Branden Robinson <g.branden.robinson@gmail.com>
+
 	[tmac]: Add Russian language support (5/7).
 
 	* tmac/tmac.am (TMACNORMALFILES): Ship new Russian language
diff --git a/doc/groff.texi b/doc/groff.texi
index 7e300dbef..de83cd5d2 100644
--- a/doc/groff.texi
+++ b/doc/groff.texi
@@ -5499,6 +5499,23 @@ The remaining encodings require support that is not built-in to the GNU
 @code{troff} executable; instead, they use macro packages.
 
 @table @code
+@item koi8-r
+@cindex encoding, input, @w{KOI8-R}
+@cindex @w{KOI8-R}, input encoding
+@cindex input encoding, @w{KOI8-R}
+@pindex koi8-r.tmac
+To use @w{KOI8-R}, an encoding for the Russian language, either place
+@w{@samp{.mso koi8-r.tmac}} at the very beginning of your document or
+supply @samp{-mkoi8-r} as a command-line argument to @code{groff}.  The
+localization file @file{ru.tmac} takes care of this automatically; see
+@ref{Manipulating Hyphenation}.@footnote{KOI8-R code points in the range
+@code{0x80}--@code{0x9F} are not valid input on systems using ISO
+character codings natively; see @code{Identifiers}.  This should be no
+impediment to practical documents, as these KOI8-R code points do not
+encode letters, but box-drawing symbols and characters that are better
+obtained via special character escape sequences; see the
+@cite{groff_char@r{(7)}} man page.}
+
 @item latin2
 @cindex encoding, input, @w{Latin-2} (ISO @w{8859-2})
 @cindex @w{Latin-2} (ISO @w{8859-2}), input encoding
@@ -8507,6 +8524,7 @@ together because they contradict; for instance, values 4 and@tie{}16,
 and values 8 and@tie{}32.  As noted, it is superfluous to add 1 to any
 nonzero even mode.
 
+@c TODO: Add @pindex for hyphenation pattern and exception files.
 @cindex hyphenation pattern files
 @cindex pattern files, for hyphenation
 The automatic placement of hyphens in words is determined by
@@ -8554,6 +8572,7 @@ the @cite{groff_tmac@r{(5)}} man page for more information on GNU
 @item        German traditional @tab det          @tab 2        @tab 2
 @item        German reformed    @tab den          @tab 2        @tab 2
 @item        Italian            @tab it           @tab 2        @tab 2
+@item        Russian            @tab ru           @tab 2        @tab 2
 @item        Swedish            @tab sv           @tab 1        @tab 2
 @end multitable
 
@@ -8637,18 +8656,21 @@ be used.  By default, every code maps to itself except those for letters
 @pindex fr.tmac
 @pindex it.tmac
 @pindex ja.tmac
+@pindex ru.tmac
 @pindex sv.tmac
 @pindex zh.tmac
 The set of hyphenation patterns is associated with the language set by
 the @code{hla} request (see below).  The @code{hpf} request is usually
 invoked by a localization file loaded by the @file{troffrc} file.  By
 default, @file{troffrc} loads the localization file for
-English.@footnote{As of @code{groff} 1.23.0, localization files for
-Czech (@code{cs}), German (@code{de}), English (@code{en}), French
-(@code{fr}), Italian (@code{it}), Japanese (@code{ja}), Swedish
-(@code{sv}), and Chinese (@code{zh}) exist.}  For Western languages, the
-localization file sets the hyphenation mode and loads hyphenation
-patterns and exceptions.
+English.@footnote{As of @code{groff}
+@c XXX 1.23.0
+1.23.0++,
+localization files for Czech (@code{cs}), German (@code{de}), English
+(@code{en}), French (@code{fr}), Italian (@code{it}), Japanese
+(@code{ja}), Russian (@code{ru}), Swedish (@code{sv}), and Chinese
+(@code{zh}) exist.}  For Western languages, the localization file sets
+the hyphenation mode and loads hyphenation patterns and exceptions.
 
 A second call to @code{hpf} (for the same language) replaces the
 hyphenation patterns with the new ones.  Invoking @code{hpf} or
diff --git a/doc/ms.ms b/doc/ms.ms
index a3573e6b4..e532f7356 100644
--- a/doc/ms.ms
+++ b/doc/ms.ms
@@ -3006,11 +3006,12 @@ provides several strings that you can customize for your own purposes,
 or redefine to adapt the macro package to languages other than English.
 .
 It is already localized for
-.\" cs, de, fr, it, sv
+.\" cs, de, fr, it, ru, sv
 Czech,
 German,
 French,
 Italian,
+Russian,
 and
 Swedish.
 .
diff --git a/man/groff.7.man b/man/groff.7.man
index e16ec458f..b2abf52a2 100644
--- a/man/groff.7.man
+++ b/man/groff.7.man
@@ -6374,10 +6374,13 @@ English
 .RI ( en ),
 French
 .RI ( fr ),
+.\" XXX: FIXME
 Japanese
 .RI ( it ),
 Italian
 .RI ( ja ),
+Russian
+.RI ( ru ),
 Swedish
 .RI ( sv ),
 and Chinese
diff --git a/man/groff_tmac.5.man b/man/groff_tmac.5.man
index 8126e594f..6eca61cbc 100644
--- a/man/groff_tmac.5.man
+++ b/man/groff_tmac.5.man
@@ -397,6 +397,21 @@ Japanese.
 .
 .
 .TP
+.I ru
+Russian;
+localizes
+.IR man ,
+.IR me ,
+.IR mm ,
+.IR mom ,
+and
+.IR ms .
+.
+Sets the input encoding to KOI8-R by loading
+.IR koi8-r.tmac .
+.
+.
+.TP
 .I sv
 Swedish;
 localizes
@@ -460,6 +475,23 @@ loads
 automatically at startup.
 .
 .
+.TP
+.I koi8\-r
+provides support for the KOI8-R encoding.
+.
+KOI8-R code points in the range 0x80\[en]0x9F are not valid input on
+systems using ISO character codings natively;
+see section \[lq]Identifiers\[rq] in
+.MR groff @MAN7EXT@ .
+.
+This should be no impediment to practical documents,
+as these KOI8-R code points do not encode letters,
+but box-drawing symbols and characters that are better obtained via
+special character escape sequences;
+see
+.MR groff_char @MAN7EXT@ .
+.
+.
 .P
 Because different input character codes constitute valid GNU
 .I troff \" GNU