dev-libs/crypto++: add pkgconfig file for clementine

Read this bug report:
  clementine-player/Clementine#5279

Package-Manager: portage-2.2.28

dev-libs/crypto++/crypto++-5.6.2-r4.ebuild

@@ -0,0 +1,75 @@
+# Copyright 1999-2015 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+# $Id$
+
+EAPI=5
+
+inherit eutils flag-o-matic multilib toolchain-funcs autotools
+
+DESCRIPTION="C++ class library of cryptographic schemes"
+HOMEPAGE="http://cryptopp.com"
+SRC_URI="mirror://sourceforge/cryptopp/cryptopp${PV//.}.zip"
+
+LICENSE="Boost-1.0"
+SLOT="0"
+KEYWORDS="~alpha ~amd64 ~arm ~hppa ~ppc ~ppc64 ~sparc ~x86 ~x64-macos"
+IUSE="static-libs"
+
+DEPEND="app-arch/unzip
+	sys-devel/libtool"
+
+S="${WORKDIR}"
+
+src_prepare() {
+	epatch "${FILESDIR}"/${P}-r1-make.patch
+	epatch "${FILESDIR}"/${P}-cve-2015-2141.patch
+
+	# Generate our own libtool script for building.
+	cat <<-EOF > configure.ac
+	AC_INIT(lt, 0)
+	AM_INIT_AUTOMAKE
+	AC_PROG_CXX
+	LT_INIT
+	AC_CONFIG_FILES(Makefile)
+	AC_OUTPUT
+	EOF
+	touch NEWS README AUTHORS ChangeLog Makefile.am
+	eautoreconf
+}
+
+src_configure() {
+	econf $(use_enable static-libs static)
+}
+
+src_compile() {
+	# higher optimizations cause problems
+	replace-flags -O? -O1
+	filter-flags -fomit-frame-pointer
+	# ASM isn't Darwin/Mach-O ready, #479554, buildsys doesn't grok CPPFLAGS
+	[[ ${CHOST} == *-darwin* ]] && append-flags -DCRYPTOPP_DISABLE_X86ASM
+
+	emake -f GNUmakefile CXX="$(tc-getCXX)" CXXFLAGS="${CXXFLAGS}" LIBDIR="$(get_libdir)" PREFIX="${EPREFIX}/usr" LIBTOOL="./libtool"
+}
+
+src_test() {
+	# ensure that all test vectors have Unix line endings
+	local file
+	for file in TestVectors/* ; do
+		edos2unix ${file}
+	done
+
+	if ! emake CXX="$(tc-getCXX)" CXXFLAGS="${CXXFLAGS}" test ; then
+		eerror "Crypto++ self-tests failed."
+		eerror "Try to remove some optimization flags and reemerge Crypto++."
+		die "emake test failed"
+	fi
+}
+
+src_install() {
+	emake DESTDIR="${D}" LIBDIR="$(get_libdir)" PREFIX="${EPREFIX}/usr" LIBTOOL="./libtool" install
+	use static-libs || rm -f "${ED}"/usr/$(get_libdir)/*.la
+	cp "${FILESDIR}/cryptopp.pc" "${WORKDIR}" || die "Could not find pkg-config file"
+	sed -i -e "s:^prefix= :prefix= ${EPREFIX}:" -e "s:/,lib,:/$(get_libdir):g" "${WORKDIR}/cryptopp.pc"
+	insinto "/usr/$(get_libdir)/pkgconfig"
+	doins "${WORKDIR}/cryptopp.pc"
+}

dev-libs/crypto++/files/cryptopp.pc

@@ -0,0 +1,12 @@
+prefix= /usr
+exec_prefix=${prefix}
+libdir=${exec_prefix}/,lib, 
+includedir=${prefix}/include 
+
+Name: libcrypto++
+Description: General purpose cryptographic shared library
+URL: http://www.cryptopp.com
+Version: %version
+Requires:
+Libs: -lcryptopp
+Cflags: