[OE-core] [PATCH V3 2/2] populate_sdk_ext: consider custom configuration in local.conf

[Chen Qi]

Copy the contents of local.conf under TOPDIR into the final generated
local.conf. In this way, custom settings are also made into the final
local.conf like IMAGE_INSTALL, DISTRO_FEATURES, VIRTUAL-RUNTIME_xxx, etc.

Before this change, installing extensible SDK would usually report failure
when preparing the build system if the user has custom configuration for
DISTRO_FEATURES in local.conf. Also, items in IMAGE_INSTALL_append in local.conf
also don't get built correctly.

This patch solves the above problem.

A blacklist mechanism is also introduced so that we can blacklist variables that
should not be copied into the final local.conf file. Currently, the blacklist
contains 'TMPDIR', 'SSTATE_DIR', 'DL_DIR', 'STAMPS_DIR', 'BASE_WORKDIR' and
'DEPLOY_DIR'. What these variables have in common is that they are set in
bitbake.conf using '?=' or '??='.

In addition, we check to avoid any setting that might lead to host path
bleeding into SDK's configuration.

[YOCTO #7616]

Signed-off-by: Chen Qi <Qi.Chen at windriver.com>
---
 meta/classes/populate_sdk_ext.bbclass | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/meta/classes/populate_sdk_ext.bbclass b/meta/classes/populate_sdk_ext.bbclass
index 2fc4c11..49ba26b 100644
--- a/meta/classes/populate_sdk_ext.bbclass
+++ b/meta/classes/populate_sdk_ext.bbclass
@@ -16,6 +16,7 @@ SDK_RDEPENDS_append_task-populate-sdk-ext = " ${SDK_TARGETS}"
 SDK_RELOCATE_AFTER_INSTALL_task-populate-sdk-ext = "0"
 
 SDK_META_CONF_WHITELIST ?= "MACHINE DISTRO PACKAGE_CLASSES"
+SDK_META_CONF_BLACKLIST ?= "TMPDIR DL_DIR SSTATE_DIR STAMPS_DIR BASE_WORKDIR DEPLOY_DIR"
 
 SDK_TARGETS ?= "${PN}"
 OE_INIT_ENV_SCRIPT ?= "oe-init-build-env"
@@ -114,6 +115,28 @@ python copy_buildsystem () {
         f.write('# this configuration provides, it is strongly suggested that you set\n')
         f.write('# up a proper instance of the full build system and use that instead.\n\n')
 
+        # Copy configurations from the current local.conf
+        builddir = d.getVar('TOPDIR', True)
+        with open(builddir + '/conf/local.conf', 'r') as lf:
+            varblacklist = d.getVar('SDK_META_CONF_BLACKLIST', True).split()
+            skip = False
+            for line in lf:
+                line = line.lstrip()
+                if line.startswith('#'):
+                    continue
+                # avoid host path bleeding into SDK configuration
+                if line.find('"/') != -1:
+                    continue
+                for varname in varblacklist:
+                    if line.startswith(varname):
+                        skip = True
+                        break
+                if not skip:
+                    f.write(line)
+                skip = False
+        f.write('\n')
+
+        # Configurations in local.conf which are specific for extensible SDK
         f.write('INHERIT += "%s"\n\n' % 'uninative')
         f.write('CONF_VERSION = "%s"\n\n' % d.getVar('CONF_VERSION'))
 
-- 
1.9.1