doc: Makefile: add support for xelatex

This patch makes the "latexpdf" target compile the documentation with
xelatex instead of the default pdflatex engine.

The reason behind this is stated in [YOCTO #14357]: pdflatex does not
support compiling foreign characters, so we need to resort to another
engine, here xelatex.

It also increases the texmf config buf_size to 10000000 to avoid a
compilation error.

(From yocto-docs rev: 0a6944b9f90b4d3babbdec9dee18fb8195b0db06)

Signed-off-by: Antonin Godard <antonin.godard@bootlin.com>
(cherry picked from commit 93848842b3ad8aa6b9c9f46d60f2c2ad396c6971)
Signed-off-by: Antonin Godard <antonin.godard@bootlin.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/documentation/Makefile b/documentation/Makefile
index cb8d4dea85..402ad986ae 100644
--- a/documentation/Makefile
+++ b/documentation/Makefile
@@ -61,9 +61,12 @@ epub: $(PNGs)
         $(SOURCEDIR)/set_versions.py
         @$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
 
+# Note: we need to pass buf_size here (which is also configurable from
+# texmf.cnf), to avoid following error:
+#   Unable to read an entire line---bufsize=200000. Please increase buf_size in texmf.cnf.
 latexpdf: $(PDFs)
         $(SOURCEDIR)/set_versions.py
-        @$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
+        buf_size=10000000 $(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
 
 all: html epub latexpdf