[oe] [PATCHv3 1/3] conf/layer.conf: Use .= for BBPATH and += for BBFILES

[raj.khem at gmail.com]

From: Khem Raj <raj.khem at gmail.com>

Provide additional commentary that should help a bit more

Signed-off-by: Khem Raj <raj.khem at gmail.com>
Acked-by: Paul Menzel <paulepanter at users.sourceforge.net>
---
 meta-efl/conf/layer.conf   |    6 +++---
 meta-gnome/conf/layer.conf |    6 +++---
 meta-gpe/conf/layer.conf   |    6 +++---
 meta-oe/conf/layer.conf    |   21 ++++++++++++++++++---
 4 files changed, 27 insertions(+), 12 deletions(-)

diff --git a/meta-efl/conf/layer.conf b/meta-efl/conf/layer.conf
index 85dbacd..272fc04 100644
--- a/meta-efl/conf/layer.conf
+++ b/meta-efl/conf/layer.conf
@@ -1,8 +1,8 @@
-# We have a conf and classes directory, prepend to BBPATH to prefer our versions
-BBPATH := "${LAYERDIR}:${BBPATH}"
+# We have a conf and classes directory, append to BBPATH 
+BBPATH .= ":${LAYERDIR}"
 
 # We have a recipes directory, add to BBFILES
-BBFILES := "${BBFILES} ${LAYERDIR}/recipes-*/*/*.bb ${LAYERDIR}/recipes-*/*/*.bbappend"
+BBFILES += "${LAYERDIR}/recipes-*/*/*.bb ${LAYERDIR}/recipes-*/*/*.bbappend"
 
 BBFILE_COLLECTIONS += "efl-layer"
 BBFILE_PATTERN_efl-layer := "^${LAYERDIR}/"
diff --git a/meta-gnome/conf/layer.conf b/meta-gnome/conf/layer.conf
index c878ecf..902ab8f 100644
--- a/meta-gnome/conf/layer.conf
+++ b/meta-gnome/conf/layer.conf
@@ -1,8 +1,8 @@
-# We have a conf and classes directory, prepend to BBPATH to prefer our versions
-BBPATH := "${LAYERDIR}:${BBPATH}"
+# We have a conf and classes directory, append to BBPATH
+BBPATH .= ":${LAYERDIR}"
 
 # We have a recipes directory, add to BBFILES
-BBFILES := "${BBFILES} ${LAYERDIR}/recipes-*/*/*.bb ${LAYERDIR}/recipes-*/*/*.bbappend"
+BBFILES += "${LAYERDIR}/recipes-*/*/*.bb ${LAYERDIR}/recipes-*/*/*.bbappend"
 
 BBFILE_COLLECTIONS += "gnome-layer"
 BBFILE_PATTERN_gnome-layer := "^${LAYERDIR}/"
diff --git a/meta-gpe/conf/layer.conf b/meta-gpe/conf/layer.conf
index d250555..6c018b1 100644
--- a/meta-gpe/conf/layer.conf
+++ b/meta-gpe/conf/layer.conf
@@ -1,8 +1,8 @@
-# We have a conf and classes directory, prepend to BBPATH to prefer our versions
-BBPATH := "${LAYERDIR}:${BBPATH}"
+# We have a conf and classes directory, append to BBPATH
+BBPATH .= ":${LAYERDIR}"
 
 # We have a recipes directory, add to BBFILES
-BBFILES := "${BBFILES} ${LAYERDIR}/recipes-*/*/*.bb ${LAYERDIR}/recipes-*/*/*.bbappend"
+BBFILES += "${LAYERDIR}/recipes-*/*/*.bb ${LAYERDIR}/recipes-*/*/*.bbappend"
 
 BBFILE_COLLECTIONS += "gpe-layer"
 BBFILE_PATTERN_gpe-layer := "^${LAYERDIR}/"
diff --git a/meta-oe/conf/layer.conf b/meta-oe/conf/layer.conf
index 9fa60c1..267616b 100644
--- a/meta-oe/conf/layer.conf
+++ b/meta-oe/conf/layer.conf
@@ -1,9 +1,24 @@
-# We have a conf and classes directory, prepend to BBPATH to prefer our versions
-BBPATH := "${LAYERDIR}:${BBPATH}"
+# It really depends on order of the layers appearing in BBLAYERS
+# variable in toplevel bblayers.conf file, where bitbake will search
+# for .inc files and others where bitbake uses BBPATH since it will
+# search the directories from first to last as specified in BBPATH
+# Therefore if you want a given layer to be considered high priority
+# for the .inc and .conf etc. then consider it adding at the beginning
+# of BBPATH. For bblayers bitbake will use BBFILES_PRIORITY to resolve
+# the recipe contention so the order of directories in BBFILES does 
+# not matter.
+
+# We have a conf and classes directory, append to BBPATH
+BBPATH .= ":${LAYERDIR}"
 
 # We have a recipes directory, add to BBFILES
-BBFILES := "${BBFILES} ${LAYERDIR}/recipes-*/*/*.bb ${LAYERDIR}/recipes-*/*/*.bbappend"
+BBFILES += "${LAYERDIR}/recipes-*/*/*.bb ${LAYERDIR}/recipes-*/*/*.bbappend"
 
 BBFILE_COLLECTIONS += "openembedded-layer"
 BBFILE_PATTERN_openembedded-layer := "^${LAYERDIR}/"
+
+# Define the priority for recipes (.bb files) from this layer,
+# choosing carefully how this layer interacts with all of the
+# other layers.
+
 BBFILE_PRIORITY_openembedded-layer = "6"
-- 
1.7.4.1