From f19c9d2097c2c1c3e49f8a612db7268de20bbb3b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Eivind=20N=C3=A6ss?= <eivnaes@yahoo.com>
Date: Sat, 4 Mar 2023 23:26:00 +0100
Subject: [PATCH] build: detect pppd version via pkg-config for PPPD_PLUGIN_DIR

Ppp 2.5 adds a pkg-config file, so we can detect the version.
Use it.

[thaller@redhat.com: split out patch]

(cherry picked from commit 0324098afaee6e9e72050b2c8a6fb47803c36494)
(cherry picked from commit 89bde5c9caf949043cbe3bc82adb11f1eef83b92)
---
 configure.ac | 8 ++++++--
 meson.build  | 9 ++++++++-
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/configure.ac b/configure.ac
index 320eb37a6a..aa1a17c9b0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -767,13 +767,17 @@ else
 fi
 AM_CONDITIONAL(WITH_PPP, test "${enable_ppp}" = "yes")
 
+PPPD_VERSION=2.4.9
+PKG_CHECK_EXISTS([pppd], [
+	PPPD_VERSION=`$PKG_CONFIG --modversion pppd`
+])
+
 AC_ARG_WITH([pppd-plugin-dir],
             AS_HELP_STRING([--with-pppd-plugin-dir=DIR], [path to the pppd plugins directory]))
-
 if test -n "$with_pppd_plugin_dir" ; then
 	PPPD_PLUGIN_DIR="$with_pppd_plugin_dir"
 else
-	PPPD_PLUGIN_DIR="${libdir}/pppd/2.4.5"
+	PPPD_PLUGIN_DIR="${libdir}/pppd/$PPPD_VERSION"
 fi
 AC_SUBST(PPPD_PLUGIN_DIR)
 
diff --git a/meson.build b/meson.build
index 525be69c6a..7d6cdbe958 100644
--- a/meson.build
+++ b/meson.build
@@ -563,6 +563,13 @@ enable_ppp = get_option('ppp')
 if enable_ppp
   assert(cc.has_header('pppd/pppd.h'), 'couldn\'t find pppd.h. pppd development headers are required')
 
+  pppd_dep = dependency('pppd', required: false)
+  if (pppd_dep.found())
+    pppd_version = pppd_dep.version()
+  else
+    pppd_version = '2.4.9'
+  endif
+
   pppd_path = get_option('pppd')
   if pppd_path == ''
     pppd = find_program('pppd', '/sbin/pppd', '/usr/sbin/pppd', required: false)
@@ -574,7 +581,7 @@ if enable_ppp
 
   pppd_plugin_dir = get_option('pppd_plugin_dir')
   if pppd_plugin_dir == ''
-    pppd_plugin_dir = join_paths(nm_libdir, 'pppd', '2.4.5')
+    pppd_plugin_dir = join_paths(nm_libdir, 'pppd', pppd_version)
   endif
 endif
 config_h.set10('WITH_PPP', enable_ppp)