From bc3b39bde331bc673f3b5b60a9f048c91c4f7dc8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jos=C3=A9=20Exp=C3=B3sito?= <jose.exposito89@gmail.com>
Date: Mon, 20 Sep 2021 19:46:45 +0200
Subject: [PATCH] build: check if libinput supports high-res scroll

Add a project argument (LIBINPUT_HAS_SCROLL_VALUE120) to allow
building against old versions of libinput or, where high-resolution
scroll is available, support it.
---
 backend/libinput/meson.build | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/backend/libinput/meson.build b/backend/libinput/meson.build
index 44bb57e19..65175b149 100644
--- a/backend/libinput/meson.build
+++ b/backend/libinput/meson.build
@@ -27,3 +27,14 @@ wlr_files += files(
 
 features += { 'libinput-backend': true }
 wlr_deps += libinput
+
+# Check whether libinput supports high-resolution scroll or not
+libinput_supports_scroll_value120 = cc.has_function(
+	'libinput_event_pointer_get_scroll_value_v120',
+	dependencies: libinput,
+)
+
+add_project_arguments(
+	'-DLIBINPUT_HAS_SCROLL_VALUE120=@0@'.format(libinput_supports_scroll_value120.to_int()),
+	language: 'c',
+)