Some ambiguity (e.g., same-named man pages in multiple volumes)
makes it impossible to fully automate this, but the following
Python snippet (run inside the man/ directory of the systemd repo)
helped to generate the sed command lines (which were subsequently
manually reviewed, run and the false positives reverted):
from pathlib import Path
import lxml
from lxml import etree as ET
man2vol: dict[str, str] = {}
man2citerefs: dict[str, list] = {}
for file in Path(".").glob("*.xml"):
tree = ET.parse(file, lxml.etree.XMLParser(recover=True))
meta = tree.find("refmeta")
if meta is not None:
title = meta.findtext("refentrytitle")
if title is not None:
vol = meta.findtext("manvolnum")
if vol is not None:
man2vol[title] = vol
citerefs = list(tree.iter("citerefentry"))
if citerefs:
man2citerefs[title] = citerefs
for man, refs in man2citerefs.items():
for ref in refs:
title = ref.findtext("refentrytitle")
if title is not None:
has = ref.findtext("manvolnum")
try:
should_have = man2vol[title]
except KeyError: # Non-systemd man page reference? Ignore.
continue
if has != should_have:
print(
f"sed -i '\\|<citerefentry><refentrytitle>{title}"
f"</refentrytitle><manvolnum>{has}</manvolnum>"
f"</citerefentry>|s|<manvolnum>{has}</manvolnum>|"
f"<manvolnum>{should_have}</manvolnum>|' {man}.xml"
)
With <para><filename>…</filename></para>, we get a separate "paragraph" for
each line, i.e. entries separated by empty lines. This uses up a lot of space
and was only done because docbook makes it hard to insert a newline. In some
other places, <literallayout> was used, but then we cannot indent the source
text (because the whitespace would end up in the final page). We can get the
desired result with <simplelist>.
With <simplelist> the items are indented in roff output, but not in html
output. In some places this looks better then no indentation, and in others it
would probably be better to have no indent. But this is a minor issue and we
cannot control that.
(I didn't convert all spots. There's a bunch of other man pages which have two
lines, e.g. an executable and service file, and it doesn't matter there so
much.)
