[gentoo-dev] [PATCH 4/5] vcs-snapshot.eclass: Detect and report invalid directory structure

[Michał Górny]

Detect when the archive does not contain a single top-level directory,
and abort in that case.  Otherwise, --strip-components would result
in unpredictable mess.

Signed-off-by: Michał Górny <mgorny@g.o>
---
 eclass/vcs-snapshot.eclass | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/eclass/vcs-snapshot.eclass b/eclass/vcs-snapshot.eclass
index 312e9a4611e1..dbca6fd586d2 100644
--- a/eclass/vcs-snapshot.eclass
+++ b/eclass/vcs-snapshot.eclass
@@ -68,8 +68,20 @@ vcs-snapshot_src_unpack() {
 
 				debug-print "${FUNCNAME}: unpacking ${f} to ${destdir}"
 
-				# XXX: check whether the directory structure inside is
-				# fine? i.e. if the tarball has actually a parent dir.
+				local topdirs=()
+				readarray -t topdirs \
+					< <(tar -t -f "${DISTDIR}/${f}" | cut -d/ -f1 | sort -u)
+				if [[ ${#topdirs[@]} -gt 1 ]]; then
+					eerror "The archive ${f} contains multiple or no top directory."
+					eerror "It is impossible for vcs-snapshot to unpack this correctly."
+					eerror "Top directories found:"
+					local d
+					for d in "${topdirs[@]}"; do
+						eerror "    ${d}"
+					done
+					die "${FUNCNAME}: Invalid directory structure in archive ${f}"
+				fi
+
 				mkdir "${destdir}" || die
 				# -o (--no-same-owner) to avoid restoring original owner
 				einfo "Unpacking ${f}"
-- 
2.22.0