android build error on building apk

[arungowda09]

I have a cocos2d project I have done porting to axmol
version axmol 2.2.1
android studio version Android Studio Iguana | 2023.2.1 Patch 1

ld: error: unable to find library -lext_ssl
ld: error: unable to find library -lext_crypto
ld: error: unable to find library -lext_uv

can anybody help me

[rh101]

Those errors shouldn't be appearing at all. Are you somehow referencing those libraries from your CMakeLists.txt?

[arungowda09]

CMakeLists.txt
this is the 3rdparty cmake file

and I have external lib sioclient files that is added in 3rdparty folder but its not added in cmake file but in main project Cmake reference added

CMakeLists.txt
please check above 2 files

[rh101]

CMakeLists.txt this is the 3rdparty cmake file

and I have external lib sioclient files that is added in 3rdparty folder but its not added in cmake file but in main project Cmake reference added

Where did you originally get this file from before you modified it?
Never mind, it seems you copied across the Axmol 3rd party CMakeLists.txt, but this is completely unnecessary and not the correct way to be adding a library to your project.

[rh101]

To add a library to your project, you would simply add something like the following your project CMakeLists.txt:

target_link_libraries(${APP_NAME} mylib)
get_target_property(mylib_INCLUDE_DIRS mylib INTERFACE_INCLUDE_DIRECTORIES)
target_include_directories(${APP_NAME}
    PRIVATE ${mylib_INCLUDE_DIRS}
)

It needs to be put after the section where you see add_executable(${APP_NAME}), for example:

if(NOT ANDROID)
    add_executable(${APP_NAME} ${APP_SOURCES})
else()
    add_library(${APP_NAME} SHARED ${APP_SOURCES})
    # whole archive for jni
    target_link_libraries(${APP_NAME} -Wl,--whole-archive cpp_android_spec -Wl,--no-whole-archive)
    config_android_shared_libs("org.axmol.lib" "${CMAKE_CURRENT_SOURCE_DIR}/proj.android/app/src")
endif()

# >>>> ADD YOUR LIBRARY HERE <<<<
target_link_libraries(${APP_NAME} mylib)
get_target_property(mylib_INCLUDE_DIRS mylib INTERFACE_INCLUDE_DIRECTORIES)
target_include_directories(${APP_NAME}
    PRIVATE ${mylib_INCLUDE_DIRS}
)

[rh101]

If you're using libwebsockets, which is included in Cocos2d-x, then you'll need to copy it over to your project along with libuv.

For example, make a folder named "thirdparty" in the root of your project, so it would be {project_dir}/thirdparty.

Now copy websocket, uv, and cmake folders from the Cocso2d-x external folder, and put them in the {project_dir}/thirdparty that you created in your project. The cmake folder is required for the file named CocosExternalConfig.cmake, which is referenced by the websocket and uv cmake files.

To link these libraries to you project, open your {project_dir}/CMakeListst.txt, and modify it to look something like this:

if(NOT ANDROID)
    add_executable(${APP_NAME} ${APP_SOURCES})
else()
    add_library(${APP_NAME} SHARED ${APP_SOURCES})
    # whole archive for jni
    target_link_libraries(${APP_NAME} -Wl,--whole-archive cpp_android_spec -Wl,--no-whole-archive)
    config_android_shared_libs("org.axmol.lib" "${CMAKE_CURRENT_SOURCE_DIR}/proj.android/app/src")
endif()

# >>>> ADD YOUR LIBRARIES HERE <<<<
add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/thirdparty/uv ${PROJECT_BINARY_DIR}/app/thirdparty/uv)
target_link_libraries(${APP_NAME} ext_uv)

add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/thirdparty/websockets ${PROJECT_BINARY_DIR}/app/thirdparty/websockets)
target_link_libraries(${APP_NAME} ext_websockets)

To fix the OpenSSL issue, open websockets/CMakeLists.txt, and change these lines:

set_property(TARGET ${target_name} APPEND PROPERTY INTERFACE_LINK_LIBRARIES "ext_ssl")
set_property(TARGET ${target_name} APPEND PROPERTY INTERFACE_LINK_LIBRARIES "ext_crypto")
set_property(TARGET ${target_name} APPEND PROPERTY INTERFACE_LINK_LIBRARIES "ext_uv")

to:

set_property(TARGET ${target_name} APPEND PROPERTY INTERFACE_LINK_LIBRARIES "OpenSSL::SSL")
set_property(TARGET ${target_name} APPEND PROPERTY INTERFACE_LINK_LIBRARIES "OpenSSL::Crypto")
set_property(TARGET ${target_name} APPEND PROPERTY INTERFACE_LINK_LIBRARIES "ext_uv")

That should be all. Just be aware that the libwebsocket and libuv that come from Cocos2d-x are old, and may not contain the pre-built libraries for the platform you want to target for your application. If that is the case, then the only way around this is to build them from source. Information on how to do would be at the libwebsocket and libuv websites.

[arungowda09]

u mean r3dparty cmake file
from axmol engine library only

[arungowda09]

@rh101
Thank you issue resolved

[rh101]

Is there any particular reason you do not want to use the websocket implementation in Axmol?

[arungowda09]

Since we've recently updated our project from Cocos2d-x to Axmol, we're still in the process of evaluating Axmol's WebSocket implementation. At this stage, we're choosing to stick with our current old WebSocket library.