From 94ec96dd8827adfb5e272d28a4d76510e28657b3 Mon Sep 17 00:00:00 2001
From: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Date: Tue, 7 Mar 2017 22:21:28 +0100
Subject: [PATCH] Add minimal infrastructure to be able to disable extensions

This commit adds some logic to the Python build system to be able to
disable Python extensions. Follow-up commits actually add options to
disable specific extensions.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
[Peter: update for 2.7.16]
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
---
 Makefile.pre.in | 6 +++++-
 configure.ac    | 2 ++
 setup.py        | 5 ++++-
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/Makefile.pre.in b/Makefile.pre.in
index 247d3c2902..c1c98ecc5a 100644
--- a/Makefile.pre.in
+++ b/Makefile.pre.in
@@ -160,6 +160,8 @@ FILEMODE=	644
 # configure script arguments
 CONFIG_ARGS=	@CONFIG_ARGS@
 
+# disabled extensions
+DISABLED_EXTENSIONS=	@DISABLED_EXTENSIONS@
 
 # Subdirectories with code
 SRCDIRS= 	@SRCDIRS@
@@ -528,6 +530,7 @@ sharedmods: $(BUILDPYTHON) pybuilddir.txt Modules/_math.o
 	esac; \
 	$(RUNSHARED) CC='$(CC)' LDSHARED='$(BLDSHARED)' OPT='$(OPT)' \
 		_TCLTK_INCLUDES='$(TCLTK_INCLUDES)' _TCLTK_LIBS='$(TCLTK_LIBS)' \
+		DISABLED_EXTENSIONS="$(DISABLED_EXTENSIONS)" \
 		$(PYTHON_FOR_BUILD) $(srcdir)/setup.py $$quiet build
 
 # Build static library
@@ -1280,7 +1283,8 @@ libainstall:	@DEF_MAKE_RULE@ python-config
 # Install the dynamically loadable modules
 # This goes into $(exec_prefix)
 sharedinstall: sharedmods
-	$(RUNSHARED) $(PYTHON_FOR_BUILD) $(srcdir)/setup.py install \
+	$(RUNSHARED) DISABLED_EXTENSIONS="$(DISABLED_EXTENSIONS)" \
+		$(PYTHON_FOR_BUILD) $(srcdir)/setup.py install \
 	   	--prefix=$(prefix) \
 		--install-scripts=$(BINDIR) \
 		--install-platlib=$(DESTSHARED) \
diff --git a/configure.ac b/configure.ac
index 77ca6d86ca..13f90b3ddd 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2491,6 +2491,8 @@ LIBS="$withval $LIBS"
 
 PKG_PROG_PKG_CONFIG
 
+AC_SUBST(DISABLED_EXTENSIONS)
+
 # Check for use of the system expat library
 AC_MSG_CHECKING(for --with-system-expat)
 AC_ARG_WITH(system_expat,
diff --git a/setup.py b/setup.py
index 812d53d560..d426dd02ea 100644
--- a/setup.py
+++ b/setup.py
@@ -33,7 +33,10 @@ host_platform = get_platform()
 COMPILED_WITH_PYDEBUG = ('--with-pydebug' in sysconfig.get_config_var("CONFIG_ARGS"))
 
 # This global variable is used to hold the list of modules to be disabled.
-disabled_module_list = []
+try:
+    disabled_module_list = sysconfig.get_config_var("DISABLED_EXTENSIONS").split(" ")
+except KeyError:
+    disabled_module_list = list()
 
 def add_dir_to_list(dirlist, dir):
     """Add the directory 'dir' to the list 'dirlist' (at the front) if
-- 
2.11.0