eclass/unpacker: Sync with gentoo

It's from gentoo commit 26d0fb5ff1e39889d399621cc8fc796615dc3722.

sdk_container/src/third_party/portage-stable/eclass/unpacker.eclass

@@ -1,9 +1,10 @@
-# Copyright 1999-2017 Gentoo Foundation
+# Copyright 1999-2022 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
 # @ECLASS: unpacker.eclass
 # @MAINTAINER:
 # base-system@gentoo.org
+# @SUPPORTED_EAPIS: 5 6 7 8
 # @BLURB: helpers for extraneous file formats and consistent behavior across EAPIs
 # @DESCRIPTION:
 # Some extraneous file formats are not part of PMS, or are only in certain
@@ -14,10 +15,18 @@
 #  - merge rpm unpacking
 #  - support partial unpacks?
 
+case ${EAPI:-0} in
+	[5678]) ;;
+	*) die "${ECLASS}: EAPI ${EAPI:-0} not supported" ;;
+esac
+
 if [[ -z ${_UNPACKER_ECLASS} ]]; then
 _UNPACKER_ECLASS=1
 
+inherit toolchain-funcs
+
 # @ECLASS-VARIABLE: UNPACKER_BZ2
+# @USER_VARIABLE
 # @DEFAULT_UNSET
 # @DESCRIPTION:
 # Utility to use to decompress bzip2 files.  Will dynamically pick between
@@ -25,6 +34,7 @@ _UNPACKER_ECLASS=1
 # Note: this is meant for users to set, not ebuilds.
 
 # @ECLASS-VARIABLE: UNPACKER_LZIP
+# @USER_VARIABLE
 # @DEFAULT_UNSET
 # @DESCRIPTION:
 # Utility to use to decompress lzip files.  Will dynamically pick between
@@ -279,7 +289,7 @@ unpack_deb() {
 			done
 		} < "${deb}"
 	else
-		ar x "${deb}"
+		$(tc-getBUILD_AR) x "${deb}" || die
 	fi
 
 	unpacker ./data.tar*
@@ -325,6 +335,47 @@ unpack_zip() {
 	[[ $? -le 1 ]] || die "unpacking ${zip} failed (arch=unpack_zip)"
 }
 
+# @FUNCTION: unpack_7z
+# @USAGE: <7z file>
+# @DESCRIPTION:
+# Unpack 7z archives.
+unpack_7z() {
+	[[ $# -eq 1 ]] || die "Usage: ${FUNCNAME} <file>"
+
+	local p7z=$(find_unpackable_file "$1")
+	unpack_banner "${p7z}"
+	local output="$(7z x -y "${p7z}")"
+
+	if [ $? -ne 0 ]; then
+		echo "${output}" >&2
+		die "unpacking ${p7z} failed (arch=unpack_7z)"
+	fi
+}
+
+# @FUNCTION: unpack_rar
+# @USAGE: <rar file>
+# @DESCRIPTION:
+# Unpack RAR archives.
+unpack_rar() {
+	[[ $# -eq 1 ]] || die "Usage: ${FUNCNAME} <file>"
+
+	local rar=$(find_unpackable_file "$1")
+	unpack_banner "${rar}"
+	unrar x -idq -o+ "${rar}" || die "unpacking ${rar} failed (arch=unpack_rar)"
+}
+
+# @FUNCTION: unpack_lha
+# @USAGE: <lha file>
+# @DESCRIPTION:
+# Unpack LHA/LZH archives.
+unpack_lha() {
+	[[ $# -eq 1 ]] || die "Usage: ${FUNCNAME} <file>"
+
+	local lha=$(find_unpackable_file "$1")
+	unpack_banner "${lha}"
+	lha xfq "${lha}" || die "unpacking ${lha} failed (arch=unpack_lha)"
+}
+
 # @FUNCTION: _unpacker
 # @USAGE: <one archive to unpack>
 # @INTERNAL
@@ -354,6 +405,8 @@ _unpacker() {
 	*.lz)
 		: ${UNPACKER_LZIP:=$(type -P plzip || type -P pdlzip || type -P lzip)}
 		comp="${UNPACKER_LZIP} -dc" ;;
+	*.zst)
+		comp="zstd -dfc" ;;
 	esac
 
 	# then figure out if there are any archiving aspects
@@ -383,6 +436,18 @@ _unpacker() {
 		arch="unpack_zip" ;;
 	esac
 
+	# 7z, rar and lha/lzh are handled by package manager in EAPI < 8
+	if [[ ${EAPI} != [567] ]]; then
+		case ${m} in
+		*.7z)
+			arch="unpack_7z" ;;
+		*.rar|*.RAR)
+			arch="unpack_rar" ;;
+		*.LHA|*.LHa|*.lha|*.lzh)
+			arch="unpack_lha" ;;
+		esac
+	fi
+
 	# finally do the unpack
 	if [[ -z ${arch}${comp} ]] ; then
 		unpack "$1"
@@ -444,9 +509,6 @@ unpacker_src_uri_depends() {
 		case ${uri} in
 		*.cpio.*|*.cpio)
 			d="app-arch/cpio" ;;
-		*.deb)
-			# platforms like AIX don't have a good ar
-			d="kernel_AIX? ( app-arch/deb2targz )" ;;
 		*.rar|*.RAR)
 			d="app-arch/unrar" ;;
 		*.7z)
@@ -457,6 +519,10 @@ unpacker_src_uri_depends() {
 			d="app-arch/unzip" ;;
 		*.lz)
 			d="|| ( app-arch/plzip app-arch/pdlzip app-arch/lzip )" ;;
+		*.zst)
+			d="app-arch/zstd" ;;
+		*.LHA|*.LHa|*.lha|*.lzh)
+			d="app-arch/lha" ;;
 		esac
 		deps+=" ${d}"
 	done