Compile gtest as a subproject which is recommended and add a utility for…

Compile gtest as a subproject which is recommended and add a utility for downloading and building gtest source code

cmake/CMakeLists.download_gtest.in

+cmake_minimum_required(VERSION 3.6)
+
+project(googletest-download NONE)
+
+include(ExternalProject)
+ExternalProject_Add(googletest
+  GIT_REPOSITORY    https://github.com/google/googletest.git
+  GIT_TAG           release-1.8.0
+  SOURCE_DIR        "${CMAKE_BINARY_DIR}/googletest-src"
+  BINARY_DIR        "${CMAKE_BINARY_DIR}/googletest-build"
+  CONFIGURE_COMMAND ""
+  BUILD_COMMAND     ""
+  INSTALL_COMMAND   ""
+  TEST_COMMAND      ""
+)

cmake/SetupGtest.cmake

+# Setup googletest
+configure_file("${CMAKE_SOURCE_DIR}/cmake/CMakeLists.download_gtest.in" ${CMAKE_BINARY_DIR}/googletest-download/CMakeLists.txt)
+
+execute_process(COMMAND ${CMAKE_COMMAND} -G "${CMAKE_GENERATOR}" .
+                RESULT_VARIABLE result
+                WORKING_DIRECTORY ${CMAKE_BINARY_DIR}/googletest-download
+)
+if(result)
+  message(FATAL_ERROR "CMake step for googletest failed: ${result}")
+endif()
+
+execute_process(COMMAND ${CMAKE_COMMAND} --build .
+                RESULT_VARIABLE result
+                WORKING_DIRECTORY ${CMAKE_BINARY_DIR}/googletest-download
+)
+if(result)
+  message(FATAL_ERROR "Build step for googletest failed: ${result}")
+endif()
+
+set(gtest_force_shared_crt ON CACHE BOOL "" FORCE)
+
+add_subdirectory(${CMAKE_BINARY_DIR}/googletest-src
+                 ${CMAKE_BINARY_DIR}/googletest-build
+                 EXCLUDE_FROM_ALL)

test/CMakeLists.txt

@@ -12,9 +12,16 @@ foreach(PROTO ${PROTOS})
     )
 endforeach()
 
-find_path(GTEST_HEADER NAMES gtest/gtest.h)
-find_library(GTEST_LIB NAMES gtest)
-find_library(GTEST_MAIN_LIB NAMES gtest_main)
+option(BRPC_DOWNLOAD_GTEST "Download and build a fresh copy of googletest. Requires Internet access." OFF)
+set(BRPC_SYSTEM_GTEST_SOURCE_DIR "" CACHE PATH "System googletest source directory.")
+
+if(BRPC_DOWNLOAD_GTEST)
+  include(SetupGtest)
+elseif(BRPC_SYSTEM_GTEST_SOURCE_DIR)
+  add_subdirectory("${BRPC_SYSTEM_GTEST_SOURCE_DIR}" "${CMAKE_BINARY_DIR}/system-googletest-build")
+else()
+  message(FATAL_ERROR "Googletest is not available")
+endif()
 
 set(CMAKE_CPP_FLAGS "-DBRPC_WITH_GLOG=${WITH_GLOG_VAL} -DGFLAGS_NS=${GFLAGS_NS}")
 set(CMAKE_CPP_FLAGS "${CMAKE_CPP_FLAGS} -DBTHREAD_USE_FAST_PTHREAD_MUTEX -D__const__= -D_GNU_SOURCE -DUSE_SYMBOLIZE -DNO_TCMALLOC -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -D__STDC_CONSTANT_MACROS -DUNIT_TEST -Dprivate=public -Dprotected=public -DBVAR_NOT_LINK_DEFAULT_VARIABLES -D__STRICT_ANSI__ -include ${CMAKE_SOURCE_DIR}/test/sstream_workaround.h")
@@ -146,7 +153,7 @@ file(GLOB TEST_BVAR_SRCS "bvar_*_unittest.cpp")
 add_executable(test_bvar $<TARGET_OBJECTS:BUTIL_LIB>
                          ${BVAR_SOURCES}
                          ${TEST_BVAR_SRCS})
-target_link_libraries(test_bvar ${GTEST_LIB}
+target_link_libraries(test_bvar gtest
                                 ${GPERFTOOLS_LIBRARIES}
                                 ${DYNAMIC_LIB})
 
@@ -155,7 +162,7 @@ add_executable(test_butil ${TEST_BUTIL_SOURCES}
                           $<TARGET_OBJECTS:TEST_PROTO_OBJ>
                           $<TARGET_OBJECTS:BUTIL_LIB>
                           $<TARGET_OBJECTS:OBJ_LIB>)
-target_link_libraries(test_butil ${GTEST_LIB} ${GPERFTOOLS_LIBRARIES} ${DYNAMIC_LIB})
+target_link_libraries(test_butil gtest ${GPERFTOOLS_LIBRARIES} ${DYNAMIC_LIB})
 
 file(GLOB BTHREAD_UNITTESTS "bthread*unittest.cpp")
 foreach(BTHREAD_UT ${BTHREAD_UNITTESTS})
@@ -165,8 +172,7 @@ foreach(BTHREAD_UT ${BTHREAD_UNITTESTS})
                                     $<TARGET_OBJECTS:BUTIL_LIB>
                                     $<TARGET_OBJECTS:OBJ_LIB>)
     target_link_libraries(${BTHREAD_UT_WE}
-                          ${GTEST_MAIN_LIB}
-                          ${GTEST_LIB}
+                          gtest_main
                           ${GPERFTOOLS_LIBRARIES}
                           ${DYNAMIC_LIB})
 endforeach()
@@ -179,7 +185,7 @@ foreach(BRPC_UT ${BRPC_UNITTESTS})
                                  $<TARGET_OBJECTS:BUTIL_LIB>
                                  $<TARGET_OBJECTS:OBJ_LIB>)
     target_link_libraries(${BRPC_UT_WE}
-                          ${GTEST_MAIN_LIB}
+                          gtest_main
                           ${GPERFTOOLS_LIBRARIES}
                           ${GTEST_LIB}
                           ${DYNAMIC_LIB})