Generate cpp_cummy_build.cpp dynamically

Generate programs/test/cpp_dummy_build.cpp dynamically instead of
maintaining it manually. This removes the need to update it when the list of
headers changes.

Include all the headers unconditionally except for the ones that cannot be
included directly.

Support this dynamic generation both with make and with cmake.

Adapt all.sh accordingly. Remove the redundant C build from
component_build_default_make_gcc_and_cxx (it was also done in
component_test_default_out_of_box), leaving a component_test_make_cxx. Also
run the C++ program, because why not. Do this in the full configuration
which may catch a bit more problems in headers.

Fixes #2570 for good.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>

programs/.gitignore

@@ -56,6 +56,7 @@ ssl/ssl_server
 ssl/ssl_server2
 test/benchmark
 test/cpp_dummy_build
+test/cpp_dummy_build.cpp
 test/ecp-bench
 test/query_compile_time_config
 test/selftest

programs/Makefile

@@ -331,6 +331,10 @@ test/benchmark$(EXEXT): test/benchmark.c $(DEP)
 	echo "  CC    test/benchmark.c"
 	$(CC) $(LOCAL_CFLAGS) $(CFLAGS) test/benchmark.c   $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
 
+test/cpp_dummy_build.cpp: test/generate_cpp_dummy_build.sh
+	echo "  Gen   test/cpp_dummy_build.cpp"
+	test/generate_cpp_dummy_build.sh
+
 test/cpp_dummy_build$(EXEXT): test/cpp_dummy_build.cpp $(DEP)
 	echo "  CXX   test/cpp_dummy_build.cpp"
 	$(CXX) $(LOCAL_CXXFLAGS) $(CXXFLAGS) test/cpp_dummy_build.cpp   $(LOCAL_LDFLAGS) $(LDFLAGS) -o $@
@@ -391,10 +395,11 @@ clean:
 ifndef WINDOWS
 	rm -f $(EXES)
 	-rm -f ssl/ssl_pthread_server$(EXEXT)
-	-rm -f test/cpp_dummy_build$(EXEXT)
+	-rm -f test/cpp_dummy_build.cpp test/cpp_dummy_build$(EXEXT)
 else
 	if exist *.o del /Q /F *.o
 	if exist *.exe del /Q /F *.exe
+	if exist test\cpp_dummy_build.cpp del /Q /F test\cpp_dummy_build.cpp
 endif
 	$(MAKE) -C fuzz clean
 

programs/test/CMakeLists.txt

@@ -14,7 +14,17 @@ set(executables_mbedcrypto
 )
 
 if(TEST_CPP)
-    list(APPEND executables_mbedcrypto cpp_dummy_build)
+    set(cpp_dummy_build_cpp "${CMAKE_CURRENT_BINARY_DIR}/cpp_dummy_build.cpp")
+    set(generate_cpp_dummy_build "${CMAKE_CURRENT_SOURCE_DIR}/generate_cpp_dummy_build.sh")
+    add_custom_command(
+        OUTPUT "${cpp_dummy_build_cpp}"
+        COMMAND "${generate_cpp_dummy_build}" "${cpp_dummy_build_cpp}"
+        DEPENDS "${generate_cpp_dummy_build}"
+        WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
+    )
+    add_executable(cpp_dummy_build "${cpp_dummy_build_cpp}")
+    target_include_directories(cpp_dummy_build PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/../../include)
+    target_link_libraries(cpp_dummy_build ${mbedcrypto_target})
 endif()
 
 foreach(exe IN LISTS executables_libs executables_mbedcrypto)

programs/test/cpp_dummy_build.cpp

@@ -1,98 +0,0 @@
-/*
- *  This program is a dummy C++ program to ensure Mbed TLS library header files
- *  can be included and built with a C++ compiler.
- *
- *  Copyright The Mbed TLS Contributors
- *  SPDX-License-Identifier: Apache-2.0
- *
- *  Licensed under the Apache License, Version 2.0 (the "License"); you may
- *  not use this file except in compliance with the License.
- *  You may obtain a copy of the License at
- *
- *  http://www.apache.org/licenses/LICENSE-2.0
- *
- *  Unless required by applicable law or agreed to in writing, software
- *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
- *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- *  See the License for the specific language governing permissions and
- *  limitations under the License.
- */
-
-#include "mbedtls/build_info.h"
-
-#include "mbedtls/aes.h"
-#include "mbedtls/aria.h"
-#include "mbedtls/asn1.h"
-#include "mbedtls/asn1write.h"
-#include "mbedtls/base64.h"
-#include "mbedtls/bignum.h"
-#include "mbedtls/camellia.h"
-#include "mbedtls/ccm.h"
-#include "mbedtls/chacha20.h"
-#include "mbedtls/chachapoly.h"
-#include "mbedtls/check_config.h"
-#include "mbedtls/cipher.h"
-#include "mbedtls/cmac.h"
-#include "mbedtls/config_psa.h"
-#include "mbedtls/ctr_drbg.h"
-#include "mbedtls/debug.h"
-#include "mbedtls/des.h"
-#include "mbedtls/dhm.h"
-#include "mbedtls/ecdh.h"
-#include "mbedtls/ecdsa.h"
-#include "mbedtls/ecjpake.h"
-#include "mbedtls/ecp.h"
-#include "mbedtls/entropy.h"
-#include "mbedtls/error.h"
-#include "mbedtls/gcm.h"
-#include "mbedtls/hkdf.h"
-#include "mbedtls/hmac_drbg.h"
-#include "mbedtls/md.h"
-#include "mbedtls/md5.h"
-#include "mbedtls/net_sockets.h"
-#include "mbedtls/nist_kw.h"
-#include "mbedtls/oid.h"
-#include "mbedtls/pem.h"
-#include "mbedtls/pk.h"
-#include "mbedtls/pkcs12.h"
-#include "mbedtls/pkcs5.h"
-#include "mbedtls/platform_time.h"
-#include "mbedtls/platform_util.h"
-#include "mbedtls/poly1305.h"
-#include "mbedtls/psa_util.h"
-#include "mbedtls/ripemd160.h"
-#include "mbedtls/rsa.h"
-#include "mbedtls/sha1.h"
-#include "mbedtls/sha256.h"
-#include "mbedtls/sha512.h"
-#include "mbedtls/ssl.h"
-#include "mbedtls/ssl_cache.h"
-#include "mbedtls/ssl_ciphersuites.h"
-#include "mbedtls/ssl_cookie.h"
-#include "mbedtls/ssl_ticket.h"
-#include "mbedtls/threading.h"
-#include "mbedtls/timing.h"
-#include "mbedtls/version.h"
-#include "mbedtls/x509.h"
-#include "mbedtls/x509_crl.h"
-#include "mbedtls/x509_crt.h"
-#include "mbedtls/x509_csr.h"
-
-#if defined(MBEDTLS_PLATFORM_C)
-#include "mbedtls/platform.h"
-#endif
-
-#if defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C)
-#include "mbedtls/memory_buffer_alloc.h"
-#endif
-
-#include "psa/crypto.h"
-#include "psa/crypto_se_driver.h"
-
-int main()
-{
-    mbedtls_platform_context *ctx = NULL;
-    mbedtls_platform_setup(ctx);
-    mbedtls_printf("CPP Build test\n");
-    mbedtls_platform_teardown(ctx);
-}

programs/test/generate_cpp_dummy_build.sh

@@ -0,0 +1,85 @@
+#!/bin/sh
+
+# Copyright The Mbed TLS Contributors
+# SPDX-License-Identifier: Apache-2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set -e
+
+# Ensure a reproducible order for *.h
+export LC_ALL=C
+
+print_cpp () {
+  cat <<'EOF'
+/* Automatically generated file. Do not edit.
+ *
+ *  This program is a dummy C++ program to ensure Mbed TLS library header files
+ *  can be included and built with a C++ compiler.
+ *
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"); you may
+ *  not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+#include "mbedtls/build_info.h"
+
+EOF
+
+  for header in include/mbedtls/*.h include/psa/*.h; do
+    case ${header#include/} in
+      mbedtls/mbedtls_config.h) :;; # not meant for direct inclusion
+      psa/crypto_config.h) :;; # not meant for direct inclusion
+      # Some of the psa/crypto_*.h headers are not meant to be included directly.
+      # They do have include guards that make them no-ops if psa/crypto.h
+      # has been included before. Since psa/crypto.h comes before psa/crypto_*.h
+      # in the wildcard enumeration, we don't need to skip those headers.
+      *) echo "#include \"${header#include/}\"";;
+    esac
+  done
+
+  cat <<'EOF'
+
+int main()
+{
+    mbedtls_platform_context *ctx = NULL;
+    mbedtls_platform_setup(ctx);
+    mbedtls_printf("CPP Build test passed\n");
+    mbedtls_platform_teardown(ctx);
+}
+EOF
+}
+
+if [ -d include/mbedtls ]; then
+  :
+elif [ -d ../include/mbedtls ]; then
+  cd ..
+elif [ -d ../../include/mbedtls ]; then
+  cd ../..
+else
+  echo >&2 "This script must be run from an Mbed TLS source tree."
+  exit 3
+fi
+
+print_cpp >"${1:-programs/test/cpp_dummy_build.cpp}"

tests/scripts/all.sh

@@ -368,14 +368,6 @@ check_tools()
     done
 }
 
-check_headers_in_cpp () {
-    ls include/mbedtls | grep "\.h$" >headers.txt
-    <programs/test/cpp_dummy_build.cpp sed -n 's/"$//; s!^#include "mbedtls/!!p' |
-    sort |
-    diff headers.txt -
-    rm headers.txt
-}
-
 pre_parse_command_line () {
     COMMAND_LINE_COMPONENTS=
     all_except=0
@@ -1406,15 +1398,13 @@ component_build_key_exchanges () {
     tests/scripts/key-exchanges.pl
 }
 
-component_build_default_make_gcc_and_cxx () {
+component_test_make_cxx () {
-    msg "build: Unix make, -Os (gcc)" # ~ 30s
+    msg "build: Unix make, full, gcc + g++"
-    make CC=gcc CFLAGS='-Werror -Wall -Wextra -Os'
+    scripts/config.py full
+    make TEST_CPP=1 lib programs
 
-    msg "test: verify header list in cpp_dummy_build.cpp"
+    msg "test: cpp_dummy_build"
-    check_headers_in_cpp
+    programs/test/cpp_dummy_build
-
-    msg "build: Unix make, incremental g++"
-    make TEST_CPP=1
 }
 
 component_build_module_alt () {