From ed1239fce60f8cfe710637a5e0591f2b2a64b65d Mon Sep 17 00:00:00 2001
From: Paul Sokolovsky <pfalcon@users.sourceforge.net>
Date: Sat, 1 Feb 2014 20:06:55 +0200
Subject: [PATCH] Add mpconfigport.mk file to configure which modules to
 include into build.

Proof of concept, controls "ffi" module as one which requires external
dependencies.
---
 unix/Makefile        | 16 ++++++++++++----
 unix/main.c          |  2 ++
 unix/mpconfigport.mk |  4 ++++
 3 files changed, 18 insertions(+), 4 deletions(-)
 create mode 100644 unix/mpconfigport.mk

diff --git a/unix/Makefile b/unix/Makefile
index db01ccf9af..2d959bf73d 100644
--- a/unix/Makefile
+++ b/unix/Makefile
@@ -1,4 +1,5 @@
 include ../py/mkenv.mk
+-include mpconfigport.mk
 
 # define main target
 PROG = micropython
@@ -10,9 +11,16 @@ QSTR_DEFS = qstrdefsport.h
 include ../py/py.mk
 
 # compiler settings
-CFLAGS = -I. -I$(PY_SRC) -Wall -Werror -ansi -std=gnu99 -DUNIX
-CFLAGS += -I/usr/lib/libffi-3.0.13/include
-LDFLAGS = -lm -ldl -lffi
+CFLAGS = -I. -I$(PY_SRC) -Wall -Werror -ansi -std=gnu99 -DUNIX $(CFLAGS_MOD)
+LDFLAGS = $(LDFLAGS_MOD) -lm
+
+ifeq ($(MICROPY_MOD_FFI),1)
+# Note - include path below is specific to @dpgeorge
+CFLAGS_MOD += -I/usr/lib/libffi-3.0.13/include -DMICROPY_MOD_FFI=1
+LDFLAGS_MOD += -ldl -lffi
+SRC_MOD += ffi.c
+endif
+
 
 # Debugging/Optimization
 ifdef DEBUG
@@ -26,7 +34,7 @@ SRC_C = \
 	main.c \
 	file.c \
 	socket.c \
-	ffi.c \
+	$(SRC_MOD)
 
 OBJ = $(PY_O) $(addprefix $(BUILD)/, $(SRC_C:.c=.o))
 LIB = -lreadline
diff --git a/unix/main.c b/unix/main.c
index cd45e3be86..5ca8115368 100644
--- a/unix/main.c
+++ b/unix/main.c
@@ -242,7 +242,9 @@ int main(int argc, char **argv) {
 
     file_init();
     rawsocket_init();
+#if MICROPY_MOD_FFI
     ffi_init();
+#endif
 
     // Here is some example code to create a class and instance of that class.
     // First is the Python, then the C code.
diff --git a/unix/mpconfigport.mk b/unix/mpconfigport.mk
new file mode 100644
index 0000000000..d220339397
--- /dev/null
+++ b/unix/mpconfigport.mk
@@ -0,0 +1,4 @@
+# Enable/disable modules to be included in interpreter
+
+# ffi module requires libffi (libffi-dev Debian package)
+MICROPY_MOD_FFI = 0