docs/translations: Skip CJK contents if suitable fonts not found

On systems without "Noto Sans CJK" fonts, CJK chapters in
translations.pdf are full of "TOFU" boxes, with a long build time and
a large log file containing lots of missing-font warnings.

Avoid such waste of time and resources by skipping CJK chapters when
CJK fonts are not available.

To skip whole chapters, change the definition of
\kerneldocBegin{SC|TC|KR|JP} commands so that they can have an argument
to be ignored.
This works as far as the argument (#1) is not used in the command.
In place of skipped contents, put a note on skipped contents at the
beginning of the PDF.

Change the call sites in index.rst of CJK translations accordingly.

When CJK fonts are available, existing command definitions with
no argument just work.  LaTeX engine will see additional pairs of
"{" and "}", which add a level of grouping without having any effect
on typesetting.

Signed-off-by: Akira Yokosawa <akiyks@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/3359ca41-b81d-b2c7-e437-7618efbe241d@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

diff --git a/Documentation/conf.py b/Documentation/conf.py
index ded49b8e9bf63adae4bd678ae27c54e69a0386ac..62cd0e472b3b33b7c5504818eb8b26b3890cb33e 100644 (file)
--- a/Documentation/conf.py
+++ b/Documentation/conf.py
@@ -563,13 +563,18 @@ latex_elements['preamble']  += '''
        % Custom macros to on/off CJK (Dummy)
        \\newcommand{\\kerneldocCJKon}{}
        \\newcommand{\\kerneldocCJKoff}{}
-       \\newcommand{\\kerneldocBeginSC}{}
+       \\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}{}
+       \\newcommand{\\kerneldocBeginTC}[1]{}
        \\newcommand{\\kerneldocEndTC}{}
-       \\newcommand{\\kerneldocBeginKR}{}
+       \\newcommand{\\kerneldocBeginKR}[1]{}
        \\newcommand{\\kerneldocEndKR}{}
-       \\newcommand{\\kerneldocBeginJP}{}
+       \\newcommand{\\kerneldocBeginJP}[1]{}
        \\newcommand{\\kerneldocEndJP}{}
     }
 '''

diff --git a/Documentation/translations/ja_JP/index.rst b/Documentation/translations/ja_JP/index.rst
index 88d4d98eed15a3db36bea81973a9f24efdd8c648..20738c931d0255889ee43938ff82af8be20c3670 100644 (file)
--- a/Documentation/translations/ja_JP/index.rst
+++ b/Documentation/translations/ja_JP/index.rst
@@ -3,7 +3,7 @@
        \renewcommand\thesection*
        \renewcommand\thesubsection*
        \kerneldocCJKon
-       \kerneldocBeginJP
+       \kerneldocBeginJP{
 
 Japanese translations
 =====================
@@ -15,4 +15,4 @@ Japanese translations
 
 .. raw:: latex
 
-       \kerneldocEndJP
+       }\kerneldocEndJP

diff --git a/Documentation/translations/ko_KR/index.rst b/Documentation/translations/ko_KR/index.rst
index f636b482fb4c13a1a7155d35037021e508841959..4add6b2fe1f216f2eb927c68360721a0d1581380 100644 (file)
--- a/Documentation/translations/ko_KR/index.rst
+++ b/Documentation/translations/ko_KR/index.rst
@@ -3,7 +3,7 @@
        \renewcommand\thesection*
        \renewcommand\thesubsection*
        \kerneldocCJKon
-       \kerneldocBeginKR
+       \kerneldocBeginKR{
 
 한국어 번역
 ===========
@@ -26,5 +26,4 @@
 
 .. raw:: latex
 
-    \normalsize
-    \kerneldocEndKR
+    }\kerneldocEndKR

diff --git a/Documentation/translations/zh_CN/index.rst b/Documentation/translations/zh_CN/index.rst
index f831887eacfb1c30f97c2c5d8795fe59cfb0d8af..23f8f4c68e83c96c01308acec4b0f12425d6ece4 100644 (file)
--- a/Documentation/translations/zh_CN/index.rst
+++ b/Documentation/translations/zh_CN/index.rst
@@ -5,7 +5,7 @@
        \renewcommand\thesection*
        \renewcommand\thesubsection*
        \kerneldocCJKon
-       \kerneldocBeginSC
+       \kerneldocBeginSC{
 
 .. _linux_doc_zh:
 
@@ -198,4 +198,4 @@ TODOList:
 
 .. raw:: latex
 
-       \kerneldocEndSC
+       }\kerneldocEndSC

diff --git a/Documentation/translations/zh_TW/index.rst b/Documentation/translations/zh_TW/index.rst
index f56f78ba7860901958f6826587de9742fa7eee54..e1ce9d8c06f8f82a10438a2c7383678ee47aa6f3 100644 (file)
--- a/Documentation/translations/zh_TW/index.rst
+++ b/Documentation/translations/zh_TW/index.rst
@@ -5,7 +5,7 @@
        \renewcommand\thesection*
        \renewcommand\thesubsection*
        \kerneldocCJKon
-       \kerneldocBeginTC
+       \kerneldocBeginTC{
 
 .. _linux_doc_zh_tw:
 
@@ -174,4 +174,4 @@ TODOList:
 
 .. raw:: latex
 
-       \kerneldocEndTC
+       }\kerneldocEndTC