From db952fb1f64a07321410b01c327a9e9b00bf372b Mon Sep 17 00:00:00 2001
From: mikejchen <mjchen@google.com>
Date: Tue, 7 Feb 2017 17:02:40 -0800
Subject: [PATCH] Allow project to provide MBEDTLS_CPPFLAGS to customize mbed
 (#1269)

Allow another project to provide alternative MBEDTLS_CPPFLAGS
to customize things like using an alternative mbedtls-config.h
file with different settings than the default ones.
---
 configure.ac                    | 2 +-
 third_party/mbedtls/Makefile.am | 3 +--
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/configure.ac b/configure.ac
index 8f9e58c97..9ecc29815 100644
--- a/configure.ac
+++ b/configure.ac
@@ -483,7 +483,7 @@ AC_ARG_ENABLE(builtin-mbedtls,
     ],
     [enable_builtin_mbedtls=yes])
 
-if test "$enable_builtin_mbedtls" = "yes"; then
+if test "$enable_builtin_mbedtls" = "yes" -a ! "${MBEDTLS_CPPFLAGS}"; then
     MBEDTLS_CPPFLAGS="-I\${abs_top_srcdir}/third_party/mbedtls"
     MBEDTLS_CPPFLAGS="${MBEDTLS_CPPFLAGS} -I\${abs_top_srcdir}/third_party/mbedtls/repo/include"
     MBEDTLS_CPPFLAGS="${MBEDTLS_CPPFLAGS} -I\${abs_top_srcdir}/third_party/mbedtls/repo/include/mbedtls"
diff --git a/third_party/mbedtls/Makefile.am b/third_party/mbedtls/Makefile.am
index 090156c94..1d1a72a43 100644
--- a/third_party/mbedtls/Makefile.am
+++ b/third_party/mbedtls/Makefile.am
@@ -37,8 +37,7 @@ libmbedcrypto_a_CPPFLAGS                      = \
     -I$(top_srcdir)/include                     \
     -I$(top_srcdir)/src/core                    \
     -I$(MBEDTLS_SRCDIR)/include                 \
-    -I$(MBEDTLS_SRCDIR)/include/mbedtls         \
-    -DMBEDTLS_CONFIG_FILE=\"mbedtls-config.h\"  \
+    $(MBEDTLS_CPPFLAGS)                         \
     $(NULL)
 
 libmbedcrypto_a_SOURCES                       = \