接上篇文章，实现binder service 的第二种方式，这种在系统里面比较常见
先看下整体目录结构，整体差别不大。
一 android.bp 编译aidl 文件
aidl_interface {name: "libserviceaidl",srcs: ["aidl/com/test/IService.aidl","aidl/com/test/IServiceCallback.aidl",],include_dirs: ["aidl"],local_include_dir: "aidl",backend: {cpp: {enabled: true,},},versions: ["1",],
}make libserviceaidl
会报一系列错误，按照报错处理就可以了。
报错处理：
FAILED: out/soong/.intermediates/vendor/qcom/proprietary/testserver/libserviceaidl/libserviceaidl-api/checkapi_current.timestamp
echo "API dump for the current version of AIDL interface libserviceaidl does not exist." && echo Run "m libserviceaidl-update-api", or add "unstable: true" to the build rule for the interface if it does not need to be versioned && false
API dump for the current version of AIDL interface libserviceaidl does not exist.
Run m libserviceaidl-update-api, or add unstable: true to the build rule for the interface if it does not need to be versioned
执行 m libserviceaidl-update-api
[100% 352/352] //vendor/qcom/proprietary/testserver/libserviceaidl:libserviceaidl-api Making AIDL API of libserviceaidl as version current
FAILED: out/soong/.intermediates/vendor/qcom/proprietary/testserver/libserviceaidl/libserviceaidl-api/updateapi_current.timestamp
echo "module libserviceaidl-api missing dependencies: vendor/qcom/proprietary/testserver/libserviceaidl/aidl_api/libserviceaidl/1" && false
module libserviceaidl-api missing dependencies: vendor/qcom/proprietary/testserver/libserviceaidl/aidl_api/libserviceaidl/1
17:33:18 ninja failed with: exit status 1
按照提示 libserviceaidl/aidl_api/libserviceaidl/1，新建各级目录，缺少加啥，然后把aidl 文件放进去
###############################################################################
# ERROR: Backward incompatible change detected on AIDL API #
###############################################################################
Above AIDL file(s) has changed in a backward-incompatible way, e.g. removing
a method from an interface or a field from a parcelable. If a device is shipped
with this change by ignoring this message, it has a high risk of breaking later
when a module using the interface is updated, e.g., Maineline modules.
17:41:40 ninja failed with: exit status 1
把current 生成的文件放到 version １的目录，覆盖掉，保持一致就可以了。
编译成功会生成ystem/lib/libserviceaidl-V1-cpp.so ,push 到system/lib/下
二，编译Native service 和 client
cc_binary {name: "testservverfirst",srcs: ["servertest.cpp",],shared_libs: ["liblog","libcutils","libutils","libbinder","libserviceaidl-cpp", ],init_rc: ["testservver.rc"],
}cc_binary {name: "clienttest",srcs: ["clienttest.cpp", ],shared_libs: ["liblog","libcutils","libutils","libbinder","libserviceaidl-cpp", ],
}调用方式和前面文章一致，添加selinux 权限也一样。
