From d25161f1b1be4b25a8bf774a3b6d2963ff65da1e Mon Sep 17 00:00:00 2001
From: Emil Velikov <emil.l.velikov@gmail.com>
Date: Thu, 22 Aug 2024 17:04:21 +0100
Subject: [PATCH] meson: add support for building the manpages

Not as brief as the pipeline and pattern matching that (auto)make can
do, although it's fully functional ;-)

v2:
 - move man/meson.build
 - move script under scripts/

Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
---
 Makefile.am            |  2 ++
 man/meson.build        | 56 ++++++++++++++++++++++++++++++++++++++++++
 meson.build            | 10 ++++++++
 meson_options.txt      |  7 ++++++
 scripts/build-scdoc.sh |  9 +++++++
 5 files changed, 84 insertions(+)
 create mode 100644 man/meson.build
 create mode 100644 scripts/build-scdoc.sh

diff --git a/Makefile.am b/Makefile.am
index f72b3e9d..c0fe198e 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -17,9 +17,11 @@ export GCC_COLORS
 
 # meson bigs
 EXTRA_DIST += \
+	man/meson.build \
 	meson.build \
 	meson_options.txt \
 	testsuite/meson.build \
+	scripts/build-scdoc.sh \
 	scripts/kmod-symlink.sh
 
 AM_CPPFLAGS = \
diff --git a/man/meson.build b/man/meson.build
new file mode 100644
index 00000000..37da7798
--- /dev/null
+++ b/man/meson.build
@@ -0,0 +1,56 @@
+scdoc = find_program('scdoc')
+
+_man_pages = [
+  [ '5', 'depmod.d' ],
+  [ '5', 'modprobe.d' ],
+  [ '5', 'modules.dep' ],
+  [ '8', 'depmod' ],
+  [ '8', 'insmod' ],
+  [ '8', 'kmod' ],
+  [ '8', 'lsmod' ],
+  [ '8', 'modinfo' ],
+  [ '8', 'modprobe' ],
+  [ '8', 'rmmod' ],
+]
+foreach tuple : _man_pages
+  section = tuple[0]
+  man = tuple[1]
+
+  custom_target(
+    'man_@0@_@1@'.format(section, man),
+    command : [
+      build_scdoc,
+      scdoc,
+      '@INPUT@',
+      's|@SYSCONFDIR@|@0@|g;'.format(sysconfdir) +
+      's|@DISTCONFDIR@|@0@|g;'.format(distconfdir) +
+      's|@MODULE_DIRECTORY@|@0@|g;'.format(moduledir),
+    ],
+    input : '@0@.@1@.scd'.format(man, section),
+    output : '@0@.@1@'.format(man, section),
+    capture : true,
+    build_by_default : get_option('manpages'),
+    install : true,
+    install_dir : join_paths(get_option('mandir'), 'man@0@'.format(section))
+  )
+endforeach
+
+_man_aliases = [
+  ['5', 'modules.dep.bin', 'modules.dep.5' ],
+]
+
+foreach tuple : _man_aliases
+  section = tuple[0]
+  man = tuple[1]
+  dest = tuple[2]
+
+  custom_target(
+    'man_@0@_@1@'.format(section, man),
+    command : ['echo', '.so @0@'.format(dest)],
+    output : '@0@.@1@'.format(man, section),
+    capture : true,
+    build_by_default : get_option('manpages'),
+    install : true,
+    install_dir : join_paths(get_option('mandir'), 'man@0@'.format(section))
+  )
+endforeach
diff --git a/meson.build b/meson.build
index e52c7b4f..b8de6259 100644
--- a/meson.build
+++ b/meson.build
@@ -408,6 +408,15 @@ if get_option('build-tests')
   subdir('testsuite')
 endif
 
+# ------------------------------------------------------------------
+# documentation
+# ------------------------------------------------------------------
+
+if get_option('manpages')
+  build_scdoc = find_program('scripts/build-scdoc.sh')
+  subdir('man')
+endif
+
 summary({
   'moduledir'   : moduledir,
   'prefix'      : get_option('prefix'),
@@ -423,6 +432,7 @@ summary({
   'logging'     : get_option('logging'),
   'debug'       : get_option('debug-messages'),
   'build-tests' : get_option('build-tests'),
+  'man'         : get_option('manpages'),
 }, section : 'Options')
 
 summary({
diff --git a/meson_options.txt b/meson_options.txt
index 848052ae..538bef68 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -78,3 +78,10 @@ option(
   value : false,
   description : 'Always build the test suite. Default: false',
 )
+
+option(
+  'manpages',
+  type : 'boolean',
+  value : true,
+  description : 'Build the manpages. Default: true',
+)
diff --git a/scripts/build-scdoc.sh b/scripts/build-scdoc.sh
new file mode 100644
index 00000000..66aa673d
--- /dev/null
+++ b/scripts/build-scdoc.sh
@@ -0,0 +1,9 @@
+#!/bin/bash
+
+set -euo pipefail
+
+SCDOC=$1
+INPUT=$2
+SED_PATTERN=$3
+
+cat $INPUT | sed -e $SED_PATTERN | $SCDOC