python3: split python target configuration into own class

Setting _PYTHON_SYSCONFIGDATA_NAME in python3native class globally was
problematic as it was leaking into host python environment, which
was causing tracebacks depending on host distro and action
(typically anything involving importing sysconfig module).

The new class sets the variable only in specific tasks where it is needed,
and should be inherited explicitly:
- use python3native to run scripts with native python
- use python3targetconfig to run scripts with native python
if those scripts need to access target config data (such
as correct installation directories). This also adds a dependency
on target python, so should be used carefully to avoid lengthening builds.

Signed-off-by: Alexander Kanavin <alex.kanavin@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
(cherry picked from commit 5a118d4e7985fa88f04c3611f8db813f0dafce75)
Signed-off-by: Steve Sakoman <steve@sakoman.com>

diff --git a/meta/classes/python3native.bbclass b/meta/classes/python3native.bbclass
index d98fb4c7583166c3f3fc0185d5a07e9a90483d28..2e3a88c1263991ab3ea930b8f4357efb4951cd4c 100644 (file)
--- a/meta/classes/python3native.bbclass
+++ b/meta/classes/python3native.bbclass
@@ -17,8 +17,6 @@ export STAGING_LIBDIR
 export PYTHON_LIBRARY="${STAGING_LIBDIR}/lib${PYTHON_DIR}${PYTHON_ABI}.so"
 export PYTHON_INCLUDE_DIR="${STAGING_INCDIR}/${PYTHON_DIR}${PYTHON_ABI}"
 
-export _PYTHON_SYSCONFIGDATA_NAME="_sysconfigdata"
-
 # suppress host user's site-packages dirs.
 export PYTHONNOUSERSITE = "1"
 

diff --git a/meta/classes/python3targetconfig.bbclass b/meta/classes/python3targetconfig.bbclass
new file mode 100644 (file)
index 0000000..640d0c9
--- /dev/null
+++ b/meta/classes/python3targetconfig.bbclass
@@ -0,0 +1,15 @@
+inherit python3native
+
+DEPENDS_append = " python3"
+
+do_configure_prepend() {
+        export _PYTHON_SYSCONFIGDATA_NAME="_sysconfigdata"
+}
+
+do_compile_prepend() {
+        export _PYTHON_SYSCONFIGDATA_NAME="_sysconfigdata"
+}
+
+do_install_prepend() {
+        export _PYTHON_SYSCONFIGDATA_NAME="_sysconfigdata"
+}