New eclass to determine udevdir from udev.pc pkg-config file as requested by many people, without ML review due to unproductive feedback

1 files changed, 56 insertions, 0 deletions

diff --git a/eclass/udev.eclass b/eclass/udev.eclass
new file mode 100644
index 000000000000..1211d2584f08
--- /dev/null
+++ b/eclass/udev.eclass
@@ -0,0 +1,56 @@
+# Copyright 1999-2012 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+# $Header: /var/cvsroot/gentoo-x86/eclass/udev.eclass,v 1.1 2012/10/30 19:08:39 ssuominen Exp $
+
+# @ECLASS: udev.eclass
+# @MAINTAINER:
+# udev-bugs@gentoo.org
+# @BLURB: Default eclass for determining udev directories.
+# @DESCRIPTION:
+# Default eclass for determining udev directories.
+# @EXAMPLE:
+#
+# @CODE
+# inherit udev
+#
+# RDEPEND=">=sys-fs/udev-171-r6"
+# DEPEND="${RDEPEND}"
+#
+# src_configure() {
+#	econf --with-udevdir="$(udev_get_udevdir)"
+# }
+# @CODE
+
+inherit toolchain-funcs
+
+case ${EAPI:-0} in
+	0|1|2|3|4) ;;
+	*) die "${ECLASS}.eclass API in EAPI ${EAPI} not yet established."
+esac
+
+RDEPEND=""
+DEPEND="virtual/pkgconfig"
+
+# @FUNCTION: _udev_get_udevdir
+# @INTERNAL
+# @DESCRIPTION:
+# Get unprefixed udevdir.
+_udev_get_udevdir() {
+	if $($(tc-getPKG_CONFIG) --exists udev); then
+		echo -n "$($(tc-getPKG_CONFIG) --variable=udevdir udev)"
+	else
+		echo -n /lib/udev
+	fi
+}
+
+# @FUNCTION: udev_get_udevdir
+# @DESCRIPTION:
+# Output the path for the udev directory (not including ${D}).
+# This function always succeeds, even if udev is not installed.
+# The fallback value is set to /lib/udev
+udev_get_udevdir() {
+	has "${EAPI:-0}" 0 1 2 && ! use prefix && EPREFIX=
+	debug-print-function ${FUNCNAME} "${@}"
+
+	echo -n "${EPREFIX}$(_udev_get_udevdir)"
+}