Enable cross building for Android and iOS

CMakeLists.txt

@@ -4,4 +4,11 @@ project(cmake_wrapper)
 include(conanbuildinfo.cmake)
 conan_basic_setup()
 
+if(NOT Protobuf_PROTOC_EXECUTABLE)
+    message(FATAL_ERROR "Expected Conan to provide: 'Protobuf_PROTOC_EXECUTABLE'")
+endif()
+# GRPC will find the wrong protoc when cross building.
+# Override it here.
+set(_gRPC_PROTOBUF_PROTOC_EXECUTABLE ${Protobuf_PROTOC_EXECUTABLE})
+
 add_subdirectory("source_subfolder")

conandata.yml

@@ -32,3 +32,7 @@ sources:
   "1.34.1":
     url: https://github.com/grpc/grpc/archive/v1.34.1.zip
     sha256: 0884778ef7866c2aaa9c06abd820f2ba2b514edcc5ec21bda74f3b7253036f9d
+patches:
+  "1.34.1":
+    - patch_file: "patches/upstream-pr-24959-only-openssl-engine-when-supported.patch"
+      base_path: "source_subfolder"

conanfile.py

@@ -11,7 +11,7 @@ class grpcConan(ConanFile):
     url = "https://github.com/inexorgame/conan-grpc"
     homepage = "https://github.com/grpc/grpc"
     license = "Apache-2.0"
-    exports_sources = ["CMakeLists.txt"]
+    exports_sources = ["CMakeLists.txt", "patches/*"]
     generators = "cmake", "cmake_find_package_multi"
     short_paths = True
 
@@ -54,6 +54,13 @@ class grpcConan(ConanFile):
         "re2/20201101"
     )
 
+    def build_requirements(self):
+        self.build_requires("protobuf/3.13.0")
+
+        # When cross building the recipe depends on itself to provide the plugins
+        if tools.cross_building(self.settings):
+            self.build_requires("{}/{}@{}/{}".format(self.name, self.version, self.user, self.channel))
+
     def configure(self):
         if self.settings.os == "Windows" and self.settings.compiler == "Visual Studio":
             del self.options.fPIC
@@ -98,13 +105,13 @@ def _configure_cmake(self):
         cmake.definitions["gRPC_PROTOBUF_PROVIDER"] = "package"
         cmake.definitions["gRPC_RE2_PROVIDER"] = "package"
 
-        cmake.definitions["gRPC_BUILD_GRPC_CPP_PLUGIN"] = self.options.build_cpp_plugin
-        cmake.definitions["gRPC_BUILD_GRPC_CSHARP_PLUGIN"] = self.options.build_csharp_plugin
-        cmake.definitions["gRPC_BUILD_GRPC_NODE_PLUGIN"] = self.options.build_node_plugin
-        cmake.definitions["gRPC_BUILD_GRPC_OBJECTIVE_C_PLUGIN"] = self.options.build_objective_c_plugin
-        cmake.definitions["gRPC_BUILD_GRPC_PHP_PLUGIN"] = self.options.build_php_plugin
-        cmake.definitions["gRPC_BUILD_GRPC_PYTHON_PLUGIN"] = self.options.build_python_plugin
-        cmake.definitions["gRPC_BUILD_GRPC_RUBY_PLUGIN"] = self.options.build_ruby_plugin
+        cmake.definitions["gRPC_BUILD_GRPC_CPP_PLUGIN"] = self.options.build_cpp_plugin and not tools.cross_building(self.settings)
+        cmake.definitions["gRPC_BUILD_GRPC_CSHARP_PLUGIN"] = self.options.build_csharp_plugin and not tools.cross_building(self.settings)
+        cmake.definitions["gRPC_BUILD_GRPC_NODE_PLUGIN"] = self.options.build_node_plugin and not tools.cross_building(self.settings)
+        cmake.definitions["gRPC_BUILD_GRPC_OBJECTIVE_C_PLUGIN"] = self.options.build_objective_c_plugin and not tools.cross_building(self.settings)
+        cmake.definitions["gRPC_BUILD_GRPC_PHP_PLUGIN"] = self.options.build_php_plugin and not tools.cross_building(self.settings)
+        cmake.definitions["gRPC_BUILD_GRPC_PYTHON_PLUGIN"] = self.options.build_python_plugin and not tools.cross_building(self.settings)
+        cmake.definitions["gRPC_BUILD_GRPC_RUBY_PLUGIN"] = self.options.build_ruby_plugin and not tools.cross_building(self.settings)
 
         # see https://github.com/inexorgame/conan-grpc/issues/39
         if self.settings.os == "Windows":
@@ -117,6 +124,9 @@ def _configure_cmake(self):
         return cmake
 
     def build(self):
+        for patch in self.conan_data.get("patches", {}).get(self.version, []):
+            tools.patch(**patch)
+
         cmake = self._configure_cmake()
         cmake.build()
 

patches/upstream-pr-24959-only-openssl-engine-when-supported.patch

@@ -0,0 +1,51 @@
+commit e3918f40fb45dc569d8c068c179dd086b89bc938
+Author: jiangtaoli2016 <jiangtao@google.com>
+Date:   Thu Dec 10 08:51:25 2020 -0800
+
+    Only enable OpenSSL Engine when compiler supports it
+
+diff --git a/src/core/tsi/ssl_transport_security.cc b/src/core/tsi/ssl_transport_security.cc
+index ad9f5704bf..c6a8580021 100644
+--- a/src/core/tsi/ssl_transport_security.cc
++++ b/src/core/tsi/ssl_transport_security.cc
+@@ -141,7 +141,7 @@ struct tsi_ssl_frame_protector {
+ static gpr_once g_init_openssl_once = GPR_ONCE_INIT;
+ static int g_ssl_ctx_ex_factory_index = -1;
+ static const unsigned char kSslSessionIdContext[] = {'g', 'r', 'p', 'c'};
+-#ifndef OPENSSL_IS_BORINGSSL
++#if !defined(OPENSSL_IS_BORINGSSL) && !defined(OPENSSL_NO_ENGINE)
+ static const char kSslEnginePrefix[] = "engine:";
+ #endif
+
+@@ -592,7 +592,7 @@ static tsi_result ssl_ctx_use_certificate_chain(SSL_CTX* context,
+   return result;
+ }
+
+-#ifndef OPENSSL_IS_BORINGSSL
++#if !defined(OPENSSL_IS_BORINGSSL) && !defined(OPENSSL_NO_ENGINE)
+ static tsi_result ssl_ctx_use_engine_private_key(SSL_CTX* context,
+                                                  const char* pem_key,
+                                                  size_t pem_key_size) {
+@@ -665,7 +665,7 @@ static tsi_result ssl_ctx_use_engine_private_key(SSL_CTX* context,
+   if (engine_name != nullptr) gpr_free(engine_name);
+   return result;
+ }
+-#endif /* OPENSSL_IS_BORINGSSL */
++#endif /* !defined(OPENSSL_IS_BORINGSSL) && !defined(OPENSSL_NO_ENGINE) */
+
+ static tsi_result ssl_ctx_use_pem_private_key(SSL_CTX* context,
+                                               const char* pem_key,
+@@ -696,11 +696,11 @@ static tsi_result ssl_ctx_use_pem_private_key(SSL_CTX* context,
+ static tsi_result ssl_ctx_use_private_key(SSL_CTX* context, const char* pem_key,
+                                           size_t pem_key_size) {
+ // BoringSSL does not have ENGINE support
+-#ifndef OPENSSL_IS_BORINGSSL
++#if !defined(OPENSSL_IS_BORINGSSL) && !defined(OPENSSL_NO_ENGINE)
+   if (strncmp(pem_key, kSslEnginePrefix, strlen(kSslEnginePrefix)) == 0) {
+     return ssl_ctx_use_engine_private_key(context, pem_key, pem_key_size);
+   } else
+-#endif /* OPENSSL_IS_BORINGSSL */
++#endif /* !defined(OPENSSL_IS_BORINGSSL) && !defined(OPENSSL_NO_ENGINE) */
+   {
+     return ssl_ctx_use_pem_private_key(context, pem_key, pem_key_size);
+   }

test_package/CMakeLists.txt

@@ -10,21 +10,24 @@ endif()
 set(CMAKE_CXX_STANDARD 11)
 
 # Find Protobuf installation
-
 set(protobuf_MODULE_COMPATIBLE TRUE)
 find_package(protobuf CONFIG REQUIRED)
 message(STATUS "Using protobuf ${protobuf_VERSION}")
+if(NOT Protobuf_PROTOC_EXECUTABLE)
+    message(FATAL_ERROR "Expected Conan to provide: 'Protobuf_PROTOC_EXECUTABLE'")
+endif()
 
 set(_PROTOBUF_LIBPROTOBUF protobuf::libprotobuf)
-# set(_PROTOBUF_PROTOC $<TARGET_FILE:protobuf::protoc>)
-find_program(_PROTOBUF_PROTOC protoc ${CONAN_BIN_DIRS_PROTOBUF} NO_DEFAULT_PATH)
 
 # Find gRPC installation
 find_package(gRPC CONFIG REQUIRED)
-# find_package(protoc CONFIG REQUIRED)
 message(STATUS "Using gRPC ${gRPC_VERSION}")
 
-set(_GRPC_CPP_PLUGIN_EXECUTABLE $<TARGET_FILE:gRPC::grpc_cpp_plugin>)
+# Find GRPC_CPP_PLUGIN_EXECUTABLE
+find_program(_GRPC_CPP_PLUGIN_EXECUTABLE grpc_cpp_plugin REQUIRED)
+if(NOT _GRPC_CPP_PLUGIN_EXECUTABLE)
+    message(FATAL_ERROR "${_GRPC_CPP_PLUGIN_EXECUTABLE} but required!")
+endif()
 
 # Proto file
 get_filename_component(hw_proto "helloworld.proto" ABSOLUTE)
@@ -37,7 +40,7 @@ set(hw_grpc_srcs "${CMAKE_CURRENT_BINARY_DIR}/helloworld.grpc.pb.cc")
 set(hw_grpc_hdrs "${CMAKE_CURRENT_BINARY_DIR}/helloworld.grpc.pb.h")
 add_custom_command(
       OUTPUT "${hw_proto_srcs}" "${hw_proto_hdrs}" "${hw_grpc_srcs}" "${hw_grpc_hdrs}"
-      COMMAND ${_PROTOBUF_PROTOC}
+      COMMAND ${Protobuf_PROTOC_EXECUTABLE}
       ARGS --grpc_out "${CMAKE_CURRENT_BINARY_DIR}"
         --cpp_out "${CMAKE_CURRENT_BINARY_DIR}"
         -I "${hw_proto_path}"

test_package/conanfile.py

@@ -6,6 +6,11 @@ class TestPackageConan(ConanFile):
     settings = "os", "compiler", "build_type", "arch"
     generators = "cmake", "cmake_find_package_multi"
 
+    def build_requirements(self):
+        self.build_requires("protobuf/3.13.0")
+        if tools.cross_building(self.settings):
+            self.build_requires(str(self.requires['grpc']))
+
     def build(self):
         cmake = CMake(self)
         cmake.configure()