[Buildroot] [PATCH] infra/pkg-generic: ensure absolute paths in config-script fixups

[Yann E. MORIN]

In case a config script is called from a relative path, the $(dirnale
$0) would return a relative path too.

Those paths are usually parts of includes or libraries search
directories, and the packagfes buildsystems may chdir() anywhere, and
thus the relative path will no longer be valid. For example:

  $ ./host/powerpc-buildroot-linux-uclibc/sysroot/usr/bin/net-snmp-config --cflags
  [...] -I./host/powerpc-buildroot-linux-uclibc/sysroot/usr/bin/../../.././bin/../powerpc-buildroot-linux-uclibc/sysroot/usr/include/libnl3 [...]

Canonicalise the path to be sure we use absolute paths.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998 at free.fr>
Cc: Thomas Petazzoni <thomas.petazzoni at bootlin.com>
---
 package/pkg-generic.mk | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/package/pkg-generic.mk b/package/pkg-generic.mk
index 887dc838a4..649a7ad187 100644
--- a/package/pkg-generic.mk
+++ b/package/pkg-generic.mk
@@ -280,8 +280,8 @@ $(BUILD_DIR)/%/.stamp_staging_installed:
 				-e "s,^\(exec_\)\?prefix=.*,\1prefix=@STAGING_DIR@/usr,g" \
 				-e "s,-I/usr/,-I at STAGING_DIR@/usr/,g" \
 				-e "s,-L/usr/,-L at STAGING_DIR@/usr/,g" \
-				-e 's, at STAGING_DIR@,$$(dirname $$0)/../..,g' \
-				-e 's, at HOST_DIR@,$$(dirname $$0)/../../../..,g' \
+				-e 's, at STAGING_DIR@,$$(dirname $$(realpath -e $$0))/../..,g' \
+				-e 's, at HOST_DIR@,$$(dirname $$(realpath -e $$0))/../../../..,g' \
 				-e "s, at BASE_DIR@,$(BASE_DIR),g" \
 				$(addprefix $(STAGING_DIR)/usr/bin/,$($(PKG)_CONFIG_SCRIPTS)) ;\
 	fi
-- 
2.14.1