使用Emscripten (Emcmake)时指定选项的问题

Question

我的问题是将CMakeLists.txt与Emscriptem一起使用，并指定输出类型和命令行选项。

我想使用一个简单的Emscripten命令，比如：emcc file.cpp -o file.html --preload-file asset_dir/，并将其更改为我可以在CMake系统中指定的内容。我尝试了一种天真的方法，将可执行文件重命名为html的扩展名，但这不起作用。我也尝试过使用-D--preload-file:PATH=asset_dir，但也不起作用。

我的CMakeLists.txt文件很小，包含在下面。我使用命令emcmake cmake -G"Unix Makefiles" -DCMAKE_BUILD_TYPE=Release -DCMAKE_CXX_COMPILER=em++ .. && emmake make来构建它。

CMAKE_MINIMUM_REQUIRED(VERSION 3.2.0 FATAL_ERROR)
PROJECT(ProjJS)

# Set typical CMAKE settings
SET(CMAKE_BUILD_TYPE_INIT "Release")
SET(CMAKE_VERBOSE_MAKEFILE OFF CACHE BOOL "Turn on Verbose Makefiles" FORCE)
set(CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/cmake/modules")

SET(CMAKE_CXX_STANDARD 11)
SET(CMAKE_CXX_STANDARD_REQUIRED ON)

SET(PROJ_SOURCES
    hello.cpp
    ....
)

set(NAME_OF_EXE "ProjJS")

set(BOOST_LIB "boost")
set(BOOST_INCLUDE_PATH "${CMAKE_SOURCE_DIR}/extlibs/")
set(BOOST_LIB_PATH "${CMAKE_SOURCE_DIR}/extlibs/boost/libs/")

add_subdirectory(extlibs/boost)


SET(BOOST_PROGRAM_OPTIONS_SOURCES
    ${BOOST_LIB_PATH}/program_options/cmdline.cpp
    ${BOOST_LIB_PATH}/program_options/config_file.cpp
    ....
)

SET(BOOST_SYSTEM_SOURCES
    ${BOOST_LIB_PATH}/system/error_code.cpp
)

ADD_EXECUTABLE(${NAME_OF_EXE} ${PROJ_SOURCES})
add_library(${BOOST_LIB} STATIC ${BOOST_PROGRAM_OPTIONS_SOURCES} ${BOOST_SYSTEM_SOURCES})
TARGET_INCLUDE_DIRECTORIES(${BOOST_LIB} PUBLIC "${BOOST_INCLUDE_PATH}")

TARGET_LINK_LIBRARIES(${NAME_OF_EXE} PUBLIC ${BOOST_LIB})
TARGET_INCLUDE_DIRECTORIES(${NAME_OF_EXE} BEFORE PRIVATE "${CMAKE_SOURCE_DIR}/include")
TARGET_INCLUDE_DIRECTORIES(${NAME_OF_EXE} BEFORE PRIVATE "${BOOST_INCLUDE_PATH}" ${PROJ_SOURCES})

Answer 1

对于输出后缀，应该可以这样做：

set(CMAKE_EXECUTABLE_SUFFIX ".html")

完整示例：

cmake_minimum_required(VERSION 2.6 FATAL_ERROR)
project(demo)

set(CMAKE_EXECUTABLE_SUFFIX ".html")

add_executable(hello tests/hello_world.cpp)

这将发出hello.html等。

对于其他标志，我找到的最好的选择是使用target_link_libraries，CMake只是将其附加到链接行，并且可以包含任何内容。例如：

target_link_libraries(binaryen_js "-s MODULARIZE")
target_link_libraries(binaryen_js "-s INITIAL_MEMORY=512MB")

这将打开模块化并将初始内存设置为512MB (来自Binaryen CMake script的示例)。