docs: pdfdocs: Pull LaTeX preamble part out of conf.py

Quote from Jon's remark [1]:

    I do notice that Documentation/conf.py is getting large and
    unapproachable.  At some future point, it might be nice to pull
    all of the latex stuff out into a separate file where it won't
    scare people who stumble into it by accident.

Pull LaTeX preamble settings added since commit 3b4c963243b1 ("docs:
conf.py: adjust the LaTeX document output") out into
sphinx/kerneldoc-preamble.sty.

It will be copied to the build directory by the added
"latex_additional_files" setting in conf.py.

As a bonus, LaTeX/TeX code can be maintained without escaping backslashes.

To compensate the loss of change history in sphinx/kerneldoc-preamble.sty,
here is a list of changes made in conf.py:

  - f7ebe6b76940 ("docs: Activate exCJK only in CJK chapters")
  - 0afd4df0d16a ("docs: pdfdocs: Prevent column squeezing by tabulary")
  - 659653c9e546 ("docs: pdfdocs: Refactor config for CJK document")
  - e291ff6f5a03 ("docs: pdfdocs: Add CJK-language-specific font settings")
  - 7eb368cc319b ("docs: pdfdocs: Choose Serif font as CJK mainfont if possible")
  - 35382965bdd2 ("docs: pdfdocs: Preserve inter-phrase space in Korean translations")
  - 77abc2c230b1 ("docs: pdfdocs: One-half spacing for CJK translations")
  - 788d28a25799 ("docs: pdfdocs: Permit AutoFakeSlant for CJK fonts")
  - 29ac9822358f ("docs: pdfdocs: Teach xeCJK about character classes of quotation marks")
  - 7c5c18bdb656 ("docs: pdfdocs: Fix typo in CJK-language specific font settings")
  - aa872e0647dc ("docs: pdfdocs: Adjust \headheight for fancyhdr")
  - 8716ef413aa5 ("docs: pdfdocs: Tweak width params of TOC")
  - 66939df53948 ("docs: pdfdocs: Switch default CJK font to KR variants")
  - 7b686a2ea1e4 ("docs: pdfdocs: Enable CJKspace in TOC for Korean titles")
  - 5d9158e3c762 ("docs/translations: Skip CJK contents if suitable fonts not found")
  - b774cc46313b ("docs: pdfdocs: Move CJK monospace font setting to main conf.py")

[1]: https://lore.kernel.org/all/87zgmr66cn.fsf@meer.lwn.net/

Suggested-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Akira Yokosawa <akiyks@gmail.com>
Link: https://lore.kernel.org/r/aaa9dca1-27c0-c414-77f3-c5587db0cc5b@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

diff --git a/Documentation/conf.py b/Documentation/conf.py
index fb8f69f..072ee31 100644 (file)
--- a/Documentation/conf.py
+++ b/Documentation/conf.py
@@ -409,188 +409,25 @@ latex_elements = {
 
     # Additional stuff for the LaTeX preamble.
     'preamble': '''
-       % Custom width parameters for TOC --- Redefine low-level commands
-       % defined in report.cls
-       \\makeatletter
-       %% Redefine \\@pnumwidth (page number width)
-       \\renewcommand*\\@pnumwidth{2.7em}
-       %% Redefine \\l@chapter (chapter list entry)
-       \\renewcommand*\\l@chapter[2]{%
-         \\ifnum \\c@tocdepth >\\m@ne
-           \\addpenalty{-\\@highpenalty}%
-           \\vskip 1.0em \\@plus\\p@
-           \\setlength\\@tempdima{1.8em}%
-           \\begingroup
-             \\parindent \\z@ \\rightskip \\@pnumwidth
-             \\parfillskip -\\@pnumwidth
-             \\leavevmode \\bfseries
-             \\advance\\leftskip\\@tempdima
-             \\hskip -\\leftskip
-             #1\\nobreak\\hfil
-             \\nobreak\\hb@xt@\\@pnumwidth{\\hss #2%
-                                        \\kern-\\p@\\kern\\p@}\\par
-             \\penalty\\@highpenalty
-           \\endgroup
-         \\fi}
-       %% Redefine \\l@section and \\l@subsection
-       \\renewcommand*\\l@section{\\@dottedtocline{1}{1.8em}{3.2em}}
-       \\renewcommand*\\l@subsection{\\@dottedtocline{2}{5em}{4.3em}}
-       \\makeatother
-       %% Sphinx < 1.8 doesn't have \\sphinxtableofcontentshook
-       \\providecommand{\\sphinxtableofcontentshook}{}
-       %% Undefine it for compatibility with Sphinx 1.7.9
-       \\renewcommand{\\sphinxtableofcontentshook}{} % Empty the hook
-       % Prevent column squeezing of tabulary.
-       \\setlength{\\tymin}{20em}
         % Use some font with UTF-8 support with XeLaTeX
         \\usepackage{fontspec}
         \\setsansfont{DejaVu Sans}
         \\setromanfont{DejaVu Serif}
         \\setmonofont{DejaVu Sans Mono}
-        % Adjust \\headheight for fancyhdr
-        \\addtolength{\\headheight}{1.6pt}
-        \\addtolength{\\topmargin}{-1.6pt}
-     ''',
+    ''',
 }
 
-# Translations have Asian (CJK) characters which are only displayed if
-# xeCJK is used
-
-latex_elements['preamble']  += '''
-    \\IfFontExistsTF{Noto Sans CJK SC}{
-       % This is needed for translations
-       \\usepackage{xeCJK}
-       \\IfFontExistsTF{Noto Serif CJK KR}{
-           \\setCJKmainfont{Noto Serif CJK KR}[AutoFakeSlant]
-       }{
-           \\setCJKmainfont{Noto Sans CJK KR}[AutoFakeSlant]
-       }
-       \\setCJKsansfont{Noto Sans CJK KR}[AutoFakeSlant]
-       \\setCJKmonofont{Noto Sans Mono CJK KR}[AutoFakeSlant]
-       \\xeCJKDeclareCharClass{HalfLeft}{`“,`‘}
-       \\xeCJKDeclareCharClass{HalfRight}{`”,`’}
-       % CJK Language-specific font choices
-       \\IfFontExistsTF{Noto Serif CJK SC}{
-           \\newCJKfontfamily[SCmain]\\scmain{Noto Serif CJK SC}[AutoFakeSlant]
-           \\newCJKfontfamily[SCserif]\\scserif{Noto Serif CJK SC}[AutoFakeSlant]
-       }{
-           \\newCJKfontfamily[SCmain]\\scmain{Noto Sans CJK SC}[AutoFakeSlant]
-           \\newCJKfontfamily[SCserif]\\scserif{Noto Sans CJK SC}[AutoFakeSlant]
-       }
-       \\newCJKfontfamily[SCsans]\\scsans{Noto Sans CJK SC}[AutoFakeSlant]
-       \\newCJKfontfamily[SCmono]\\scmono{Noto Sans Mono CJK SC}[AutoFakeSlant]
-       \\IfFontExistsTF{Noto Serif CJK TC}{
-           \\newCJKfontfamily[TCmain]\\tcmain{Noto Serif CJK TC}[AutoFakeSlant]
-           \\newCJKfontfamily[TCserif]\\tcserif{Noto Serif CJK TC}[AutoFakeSlant]
-       }{
-           \\newCJKfontfamily[TCmain]\\tcmain{Noto Sans CJK TC}[AutoFakeSlant]
-           \\newCJKfontfamily[TCserif]\\tcserif{Noto Sans CJK TC}[AutoFakeSlant]
-       }
-       \\newCJKfontfamily[TCsans]\\tcsans{Noto Sans CJK TC}[AutoFakeSlant]
-       \\newCJKfontfamily[TCmono]\\tcmono{Noto Sans Mono CJK TC}[AutoFakeSlant]
-       \\IfFontExistsTF{Noto Serif CJK KR}{
-           \\newCJKfontfamily[KRmain]\\krmain{Noto Serif CJK KR}[AutoFakeSlant]
-           \\newCJKfontfamily[KRserif]\\krserif{Noto Serif CJK KR}[AutoFakeSlant]
-       }{
-           \\newCJKfontfamily[KRmain]\\krmain{Noto Sans CJK KR}[AutoFakeSlant]
-           \\newCJKfontfamily[KRserif]\\krserif{Noto Sans CJK KR}[AutoFakeSlant]
-       }
-       \\newCJKfontfamily[KRsans]\\krsans{Noto Sans CJK KR}[AutoFakeSlant]
-       \\newCJKfontfamily[KRmono]\\krmono{Noto Sans Mono CJK KR}[AutoFakeSlant]
-       \\IfFontExistsTF{Noto Serif CJK JP}{
-           \\newCJKfontfamily[JPmain]\\jpmain{Noto Serif CJK JP}[AutoFakeSlant]
-           \\newCJKfontfamily[JPserif]\\jpserif{Noto Serif CJK JP}[AutoFakeSlant]
-       }{
-           \\newCJKfontfamily[JPmain]\\jpmain{Noto Sans CJK JP}[AutoFakeSlant]
-           \\newCJKfontfamily[JPserif]\\jpserif{Noto Sans CJK JP}[AutoFakeSlant]
-       }
-       \\newCJKfontfamily[JPsans]\\jpsans{Noto Sans CJK JP}[AutoFakeSlant]
-       \\newCJKfontfamily[JPmono]\\jpmono{Noto Sans Mono CJK JP}[AutoFakeSlant]
-       % Dummy commands for Sphinx < 2.3 (no 'extrapackages' support)
-       \\providecommand{\\onehalfspacing}{}
-       \\providecommand{\\singlespacing}{}
-       % Define custom macros to on/off CJK
-       \\newcommand{\\kerneldocCJKon}{\\makexeCJKactive\\onehalfspacing}
-       \\newcommand{\\kerneldocCJKoff}{\\makexeCJKinactive\\singlespacing}
-       \\newcommand{\\kerneldocBeginSC}{%
-           \\begingroup%
-           \\scmain%
-           \\xeCJKDeclareCharClass{FullLeft}{`“,`‘}%
-           \\xeCJKDeclareCharClass{FullRight}{`”,`’}%
-           \\renewcommand{\\CJKrmdefault}{SCserif}%
-           \\renewcommand{\\CJKsfdefault}{SCsans}%
-           \\renewcommand{\\CJKttdefault}{SCmono}%
-           \\xeCJKsetup{CJKspace = false}%
-           % For CJK ascii-art alignment
-           \\setmonofont{Noto Sans Mono CJK SC}[AutoFakeSlant]%
-       }
-       \\newcommand{\\kerneldocEndSC}{\\endgroup}
-       \\newcommand{\\kerneldocBeginTC}{%
-           \\begingroup%
-           \\tcmain%
-           \\xeCJKDeclareCharClass{FullLeft}{`“,`‘}%
-           \\xeCJKDeclareCharClass{FullRight}{`”,`’}%
-           \\renewcommand{\\CJKrmdefault}{TCserif}%
-           \\renewcommand{\\CJKsfdefault}{TCsans}%
-           \\renewcommand{\\CJKttdefault}{TCmono}%
-           \\xeCJKsetup{CJKspace = false}%
-           % For CJK ascii-art alignment
-           \\setmonofont{Noto Sans Mono CJK TC}[AutoFakeSlant]%
-       }
-       \\newcommand{\\kerneldocEndTC}{\\endgroup}
-       \\newcommand{\\kerneldocBeginKR}{%
-           \\begingroup%
-           \\krmain%
-           \\renewcommand{\\CJKrmdefault}{KRserif}%
-           \\renewcommand{\\CJKsfdefault}{KRsans}%
-           \\renewcommand{\\CJKttdefault}{KRmono}%
-           % \\xeCJKsetup{CJKspace = true} % true by default
-           % For CJK ascii-art alignment (still misaligned for Hangul)
-           \\setmonofont{Noto Sans Mono CJK KR}[AutoFakeSlant]%
-       }
-       \\newcommand{\\kerneldocEndKR}{\\endgroup}
-       \\newcommand{\\kerneldocBeginJP}{%
-           \\begingroup%
-           \\jpmain%
-           \\renewcommand{\\CJKrmdefault}{JPserif}%
-           \\renewcommand{\\CJKsfdefault}{JPsans}%
-           \\renewcommand{\\CJKttdefault}{JPmono}%
-           \\xeCJKsetup{CJKspace = false}%
-           % For CJK ascii-art alignment
-           \\setmonofont{Noto Sans Mono CJK JP}[AutoFakeSlant]%
-       }
-       \\newcommand{\\kerneldocEndJP}{\\endgroup}
-       % Single spacing in literal blocks
-       \\fvset{baselinestretch=1}
-       % To customize \\sphinxtableofcontents
-       \\usepackage{etoolbox}
-       % Inactivate CJK after tableofcontents
-       \\apptocmd{\\sphinxtableofcontents}{\\kerneldocCJKoff}{}{}
-       \\xeCJKsetup{CJKspace = true} % For inter-phrase space of Korean TOC
-    }{ % No CJK font found
-       % Custom macros to on/off CJK (Dummy)
-       \\newcommand{\\kerneldocCJKon}{}
-       \\newcommand{\\kerneldocCJKoff}{}
-       \\newcommand{\\kerneldocBeginSC}[1]{%
-           \\begin{sphinxadmonition}{note}{Note:}
-               ``Noto Sans CJK'' fonts are not found while building this PDF\\@.
-               Translations of zh\\_CN, zh\\_TW, ko\\_KR, and ja\\_JP are
-               skipped.
-           \\end{sphinxadmonition}}
-       \\newcommand{\\kerneldocEndSC}{}
-       \\newcommand{\\kerneldocBeginTC}[1]{}
-       \\newcommand{\\kerneldocEndTC}{}
-       \\newcommand{\\kerneldocBeginKR}[1]{}
-       \\newcommand{\\kerneldocEndKR}{}
-       \\newcommand{\\kerneldocBeginJP}[1]{}
-       \\newcommand{\\kerneldocEndJP}{}
-    }
-'''
-
 # Fix reference escape troubles with Sphinx 1.4.x
 if major == 1:
     latex_elements['preamble']  += '\\renewcommand*{\\DUrole}[2]{ #2 }\n'
 
+
+# Load kerneldoc specific LaTeX settings
+latex_elements['preamble'] += '''
+        % Load kerneldoc specific LaTeX settings
+       \\input{kerneldoc-preamble.sty}
+'''
+
 # With Sphinx 1.6, it is possible to change the Bg color directly
 # by using:
 #      \definecolor{sphinxnoteBgColor}{RGB}{204,255,255}
@@ -652,6 +489,11 @@ for fn in os.listdir('.'):
 # If false, no module index is generated.
 #latex_domain_indices = True
 
+# Additional LaTeX stuff to be copied to build directory
+latex_additional_files = [
+    'sphinx/kerneldoc-preamble.sty',
+]
+
 
 # -- Options for manual page output ---------------------------------------
 

diff --git a/Documentation/sphinx/kerneldoc-preamble.sty b/Documentation/sphinx/kerneldoc-preamble.sty
new file mode 100644 (file)
index 0000000..4e56cce
--- /dev/null
+++ b/Documentation/sphinx/kerneldoc-preamble.sty
@@ -0,0 +1,184 @@
+% -*- coding: utf-8 -*-
+% SPDX-License-Identifier: GPL-2.0
+%
+% LaTeX preamble for "make latexdocs" or "make pdfdocs" including:
+%   - TOC width settings
+%   - Setting of tabulary (\tymin)
+%   - Headheight setting for fancyhdr
+%   - Fontfamily settings for CJK (Chinese, Japanese, and Korean) translations
+%
+% Note on the suffix of .sty:
+%   This is not implemented as a LaTeX style file, but as a file containing
+%   plain LaTeX code to be included into preamble.
+%   ".sty" is chosen because ".tex" would cause the build scripts to confuse
+%   this file with a LaTeX main file.
+%
+% Copyright (C) 2022  Akira Yokosawa
+
+% Custom width parameters for TOC --- Redefine low-level commands
+% defined in report.cls
+\makeatletter
+%% Redefine \@pnumwidth (page number width)
+\renewcommand*\@pnumwidth{2.7em}
+%% Redefine \l@chapter (chapter list entry)
+\renewcommand*\l@chapter[2]{%
+  \ifnum \c@tocdepth >\m@ne
+    \addpenalty{-\@highpenalty}%
+    \vskip 1.0em \@plus\p@
+    \setlength\@tempdima{1.8em}%
+    \begingroup
+      \parindent \z@ \rightskip \@pnumwidth
+      \parfillskip -\@pnumwidth
+      \leavevmode \bfseries
+      \advance\leftskip\@tempdima
+      \hskip -\leftskip
+      #1\nobreak\hfil
+      \nobreak\hb@xt@\@pnumwidth{\hss #2%
+                                 \kern-\p@\kern\p@}\par
+      \penalty\@highpenalty
+    \endgroup
+  \fi}
+%% Redefine \l@section and \l@subsection
+\renewcommand*\l@section{\@dottedtocline{1}{1.8em}{3.2em}}
+\renewcommand*\l@subsection{\@dottedtocline{2}{5em}{4.3em}}
+\makeatother
+%% Sphinx < 1.8 doesn't have \sphinxtableofcontentshook
+\providecommand{\sphinxtableofcontentshook}{}
+%% Undefine it for compatibility with Sphinx 1.7.9
+\renewcommand{\sphinxtableofcontentshook}{} % Empty the hook
+% Prevent column squeezing of tabulary.
+\setlength{\tymin}{20em}
+
+% Adjust \headheight for fancyhdr
+\addtolength{\headheight}{1.6pt}
+\addtolength{\topmargin}{-1.6pt}
+
+% Translations have Asian (CJK) characters which are only displayed if
+% xeCJK is used
+\IfFontExistsTF{Noto Sans CJK SC}{
+    % This is needed for translations
+    \usepackage{xeCJK}
+    \IfFontExistsTF{Noto Serif CJK KR}{
+       \setCJKmainfont{Noto Serif CJK KR}[AutoFakeSlant]
+    }{
+       \setCJKmainfont{Noto Sans CJK KR}[AutoFakeSlant]
+    }
+    \setCJKsansfont{Noto Sans CJK KR}[AutoFakeSlant]
+    \setCJKmonofont{Noto Sans Mono CJK KR}[AutoFakeSlant]
+    \xeCJKDeclareCharClass{HalfLeft}{`“,`‘}
+    \xeCJKDeclareCharClass{HalfRight}{`”,`’}
+    % CJK Language-specific font choices
+    \IfFontExistsTF{Noto Serif CJK SC}{
+       \newCJKfontfamily[SCmain]\scmain{Noto Serif CJK SC}[AutoFakeSlant]
+       \newCJKfontfamily[SCserif]\scserif{Noto Serif CJK SC}[AutoFakeSlant]
+    }{
+       \newCJKfontfamily[SCmain]\scmain{Noto Sans CJK SC}[AutoFakeSlant]
+       \newCJKfontfamily[SCserif]\scserif{Noto Sans CJK SC}[AutoFakeSlant]
+    }
+    \newCJKfontfamily[SCsans]\scsans{Noto Sans CJK SC}[AutoFakeSlant]
+    \newCJKfontfamily[SCmono]\scmono{Noto Sans Mono CJK SC}[AutoFakeSlant]
+    \IfFontExistsTF{Noto Serif CJK TC}{
+       \newCJKfontfamily[TCmain]\tcmain{Noto Serif CJK TC}[AutoFakeSlant]
+       \newCJKfontfamily[TCserif]\tcserif{Noto Serif CJK TC}[AutoFakeSlant]
+    }{
+       \newCJKfontfamily[TCmain]\tcmain{Noto Sans CJK TC}[AutoFakeSlant]
+       \newCJKfontfamily[TCserif]\tcserif{Noto Sans CJK TC}[AutoFakeSlant]
+    }
+    \newCJKfontfamily[TCsans]\tcsans{Noto Sans CJK TC}[AutoFakeSlant]
+    \newCJKfontfamily[TCmono]\tcmono{Noto Sans Mono CJK TC}[AutoFakeSlant]
+    \IfFontExistsTF{Noto Serif CJK KR}{
+       \newCJKfontfamily[KRmain]\krmain{Noto Serif CJK KR}[AutoFakeSlant]
+       \newCJKfontfamily[KRserif]\krserif{Noto Serif CJK KR}[AutoFakeSlant]
+    }{
+       \newCJKfontfamily[KRmain]\krmain{Noto Sans CJK KR}[AutoFakeSlant]
+       \newCJKfontfamily[KRserif]\krserif{Noto Sans CJK KR}[AutoFakeSlant]
+    }
+    \newCJKfontfamily[KRsans]\krsans{Noto Sans CJK KR}[AutoFakeSlant]
+    \newCJKfontfamily[KRmono]\krmono{Noto Sans Mono CJK KR}[AutoFakeSlant]
+    \IfFontExistsTF{Noto Serif CJK JP}{
+       \newCJKfontfamily[JPmain]\jpmain{Noto Serif CJK JP}[AutoFakeSlant]
+       \newCJKfontfamily[JPserif]\jpserif{Noto Serif CJK JP}[AutoFakeSlant]
+    }{
+       \newCJKfontfamily[JPmain]\jpmain{Noto Sans CJK JP}[AutoFakeSlant]
+       \newCJKfontfamily[JPserif]\jpserif{Noto Sans CJK JP}[AutoFakeSlant]
+    }
+    \newCJKfontfamily[JPsans]\jpsans{Noto Sans CJK JP}[AutoFakeSlant]
+    \newCJKfontfamily[JPmono]\jpmono{Noto Sans Mono CJK JP}[AutoFakeSlant]
+    % Dummy commands for Sphinx < 2.3 (no 'extrapackages' support)
+    \providecommand{\onehalfspacing}{}
+    \providecommand{\singlespacing}{}
+    % Define custom macros to on/off CJK
+    \newcommand{\kerneldocCJKon}{\makexeCJKactive\onehalfspacing}
+    \newcommand{\kerneldocCJKoff}{\makexeCJKinactive\singlespacing}
+    \newcommand{\kerneldocBeginSC}{%
+       \begingroup%
+       \scmain%
+       \xeCJKDeclareCharClass{FullLeft}{`“,`‘}%
+       \xeCJKDeclareCharClass{FullRight}{`”,`’}%
+       \renewcommand{\CJKrmdefault}{SCserif}%
+       \renewcommand{\CJKsfdefault}{SCsans}%
+       \renewcommand{\CJKttdefault}{SCmono}%
+       \xeCJKsetup{CJKspace = false}%
+       % For CJK ascii-art alignment
+       \setmonofont{Noto Sans Mono CJK SC}[AutoFakeSlant]%
+    }
+    \newcommand{\kerneldocEndSC}{\endgroup}
+    \newcommand{\kerneldocBeginTC}{%
+       \begingroup%
+       \tcmain%
+       \xeCJKDeclareCharClass{FullLeft}{`“,`‘}%
+       \xeCJKDeclareCharClass{FullRight}{`”,`’}%
+       \renewcommand{\CJKrmdefault}{TCserif}%
+       \renewcommand{\CJKsfdefault}{TCsans}%
+       \renewcommand{\CJKttdefault}{TCmono}%
+       \xeCJKsetup{CJKspace = false}%
+       % For CJK ascii-art alignment
+       \setmonofont{Noto Sans Mono CJK TC}[AutoFakeSlant]%
+    }
+    \newcommand{\kerneldocEndTC}{\endgroup}
+    \newcommand{\kerneldocBeginKR}{%
+       \begingroup%
+       \krmain%
+       \renewcommand{\CJKrmdefault}{KRserif}%
+       \renewcommand{\CJKsfdefault}{KRsans}%
+       \renewcommand{\CJKttdefault}{KRmono}%
+       % \xeCJKsetup{CJKspace = true} % true by default
+       % For CJK ascii-art alignment (still misaligned for Hangul)
+       \setmonofont{Noto Sans Mono CJK KR}[AutoFakeSlant]%
+    }
+    \newcommand{\kerneldocEndKR}{\endgroup}
+    \newcommand{\kerneldocBeginJP}{%
+       \begingroup%
+       \jpmain%
+       \renewcommand{\CJKrmdefault}{JPserif}%
+       \renewcommand{\CJKsfdefault}{JPsans}%
+       \renewcommand{\CJKttdefault}{JPmono}%
+       \xeCJKsetup{CJKspace = false}%
+       % For CJK ascii-art alignment
+       \setmonofont{Noto Sans Mono CJK JP}[AutoFakeSlant]%
+    }
+    \newcommand{\kerneldocEndJP}{\endgroup}
+    % Single spacing in literal blocks
+    \fvset{baselinestretch=1}
+    % To customize \sphinxtableofcontents
+    \usepackage{etoolbox}
+    % Inactivate CJK after tableofcontents
+    \apptocmd{\sphinxtableofcontents}{\kerneldocCJKoff}{}{}
+    \xeCJKsetup{CJKspace = true} % For inter-phrase space of Korean TOC
+}{ % No CJK font found
+    % Custom macros to on/off CJK (Dummy)
+    \newcommand{\kerneldocCJKon}{}
+    \newcommand{\kerneldocCJKoff}{}
+    \newcommand{\kerneldocBeginSC}[1]{%
+       \begin{sphinxadmonition}{note}{Note:}
+           ``Noto Sans CJK'' fonts are not found while building this PDF\@.
+           Translations of zh\_CN, zh\_TW, ko\_KR, and ja\_JP are skipped.
+       \end{sphinxadmonition}}
+    \newcommand{\kerneldocEndSC}{}
+    \newcommand{\kerneldocBeginTC}[1]{}
+    \newcommand{\kerneldocEndTC}{}
+    \newcommand{\kerneldocBeginKR}[1]{}
+    \newcommand{\kerneldocEndKR}{}
+    \newcommand{\kerneldocBeginJP}[1]{}
+    \newcommand{\kerneldocEndJP}{}
+}