[source] rootfs: fail on errors in postinst scripts

[LEDE Commits]

neoraider pushed a commit to source.git, branch master:
https://git.lede-project.org/5b99693832d0307744ac16d29fb359b730fd86a3

commit 5b99693832d0307744ac16d29fb359b730fd86a3
Author: Matthias Schiffer <mschiffer at universe-factory.net>
AuthorDate: Mon Sep 26 15:25:38 2016 +0200

    rootfs: fail on errors in postinst scripts
    
    The Gluon firmware framework [1] uses postinst scripts for sanity checks.
    Make the build fail when a postinst script exits with an error to make
    these sanity checks effective.
    
    All postinst scripts in packages from the LEDE core and the packages feed
    seem to work correctly with this change and will always return 0 unless
    something is very broken.
    
    [1] https://github.com/freifunk-gluon/gluon
    
    Signed-off-by: Matthias Schiffer <mschiffer at universe-factory.net>
---
 include/rootfs.mk | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/include/rootfs.mk b/include/rootfs.mk
index 15f71ae..b161721 100644
--- a/include/rootfs.mk
+++ b/include/rootfs.mk
@@ -60,6 +60,11 @@ define prepare_rootfs
 		cd $(1); \
 		for script in ./usr/lib/opkg/info/*.postinst; do \
 			IPKG_INSTROOT=$(1) $$(which bash) $$script; \
+			ret=$$?; \
+			if [ $$ret -ne 0 ]; then \
+				echo "postinst script $$script has failed with exit code $$ret" >&2; \
+				exit 1; \
+			fi; \
 		done; \
 		for script in ./etc/init.d/*; do \
 			grep '#!/bin/sh /etc/rc.common' $$script >/dev/null || continue; \