From e896bac2af929d6c59e6fdad20b41d69d32848fd Mon Sep 17 00:00:00 2001
From: Patrick McDermott <patrick.mcdermott@libiquity.com>
Date: Sun, 04 Aug 2019 00:58:08 -0400
Subject: ob-buildopk: Check for BB tar reverse ordering bug

---
diff --git a/NEWS b/NEWS
index 27d0f14..364d868 100644
--- a/NEWS
+++ b/NEWS
@@ -3,6 +3,15 @@ opkbuild version 4.1.2+dev
 
 Released: ????-??-??
 
+Utilities:
+
+  * ob-buildopk now checks for a bug in BusyBox versions before 1.22.0
+    that causes tar to add in reverse order entries listed on standard
+    input with the -T option.  This bug causes packages to fail to
+    install and uninstall cleanly due to data files being stored after
+    the directories that contain them.  This bug was exposed by changes
+    in opkbuild version 4.1.0.
+
 opkbuild version 4.1.2
 ----------------------
 
diff --git a/src/ob-buildopk.sh b/src/ob-buildopk.sh
index dc630d1..1e661cc 100644
--- a/src/ob-buildopk.sh
+++ b/src/ob-buildopk.sh
@@ -29,6 +29,7 @@ build_opk()
 	shift 5
 	local find_not_link=
 	local touch_noderef=
+	local sort_r=
 
 	ob_info "$(ob_get_msg 'build_opk')" \
 		"${binary}_${version}_${arch}_${plat}.opk"
@@ -41,6 +42,19 @@ build_opk()
 	else
 		find_not_link='! -type l' touch_noderef=''
 	fi
+
+	# Detect whether BusyBox tar inserts files listed with -T in reverse
+	# order.
+	mkdir -p '.opkbuild'
+	touch '.opkbuild/a' '.opkbuild/b'
+	if [ x"$(printf '.opkbuild/a\n.opkbuild/b\n' | ${TAR} -c -T - | \
+			${TAR} -t | head -n 1)" = x'b' ]; then
+		sort_r='-r'
+	else
+		sort_r=''
+	fi
+	rm -f '.opkbuild/a' '.opkbuild/b'
+
 	find "${binary}.control" "${binary}.data" ${find_not_link} | xargs \
 		${TOUCH} ${touch_noderef} -t "${date}"
 
@@ -48,9 +62,9 @@ build_opk()
 	# about to tar.
 	find "${binary}.control" "${binary}.data" | xargs chown -h 0:0
 
-	(cd -- "${binary}.control" && find '.' | LC_ALL=C sort | \
+	(cd -- "${binary}.control" && find '.' | LC_ALL=C sort ${sort_r} | \
 		${TAR} -cf '../control.tar' --no-recursion -T -)
-	(cd -- "${binary}.data"    && find '.' | LC_ALL=C sort | \
+	(cd -- "${binary}.data"    && find '.' | LC_ALL=C sort ${sort_r} | \
 		${TAR} -cf '../data.tar'    --no-recursion -T -)
 	${TOUCH} -t "${date}" 'control.tar' 'data.tar'
 	${GZIP} 'control.tar' 'data.tar'
--
cgit v0.9.1