HIDL demo

发表于 分类于

简单记录，可以直接使用。

1.添加hal目录、定义hal接口

1
2
foo@bar:~$ mkdir -p vendor/realtek/common/ATV/hardware/interfaces/hello/1.0/default
foo@bar:~$ vim vendor/realtek/common/ATV/hardware/interfaces/hello/1.0/IHello.hal

接口如下： 

1
2
3
4
5
6
7
//IHello.hal

package vendor.realtek.hello@1.0;

interface IHello {
    helloWorld (string name) generates (string result);
};

2.根据hal自动生成cpp实现

1
2
3
4
5
6
foo@bar:~$ source build/envsetup.sh
foo@bar:~$ lunch
foo@bar:~$ make hidl-gen
foo@bar:~$ vim vendor/realtek/common/ATV/hardware/interfaces/hello/genImpHidl.sh
foo@bar:~$ chmod u+x vendor/realtek/common/ATV/hardware/interfaces/hello/genImpHidl.sh
foo@bar:~$ ./vendor/realtek/common/ATV/hardware/interfaces/hello/genImpHidl.sh
1
2
3
4
5
6
7
8
9
//genImpHidl.sh

PACKAGE=vendor.realtek.hello@1.0
LOC=vendor/realtek/common/ATV/hardware/interfaces/hello/1.0/default

hidl-gen -o $LOC -Lc++-impl -rvendor.realtek:vendor/realtek/common/ATV/hardware/interfaces \
    -randroid.hidl:system/libhidl/transport $PACKAGE
hidl-gen -o $LOC -Landroidbp-impl -rvendor.realtek:vendor/realtek/common/ATV/hardware/interfaces \
    -randroid.hidl:system/libhidl/transport $PACKAGE

执行genImpHidl.sh后，default目录生成Android.bp、Hello.cpp和Hello.h文件。

1_genImplHidl.png

编写Hello.cpp 

1
foo@bar:~$ vim vendor/realtek/common/ATV/hardware/interfaces/hello/1.0/default/Hello.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
//Hello.cpp

// FIXME: your file license if you have one

#include "Hello.h"

namespace vendor {
namespace realtek {
namespace hello {
namespace V1_0 {
namespace implementation {

// Methods from ::vendor::realtek::hello::V1_0::IHello follow.
Return<void> Hello::helloWorld(const hidl_string& name, helloWorld_cb _hidl_cb) {
    // TODO implement
    char buf[100];
    ::memset(buf,0,100);
    ::snprintf(buf, 100, "Hello World, %s", name.c_str());
    hidl_string result(buf);
    _hidl_cb(result);
    return Void();
}


// Methods from ::android::hidl::base::V1_0::IBase follow.

//IHello* HIDL_FETCH_IHello(const char* /* name */) {
    //return new Hello();
//}
//
}  // namespace implementation
}  // namespace V1_0
}  // namespace hello
}  // namespace realtek
}  // namespace vendor

HIDL的实现有两种方式，如果打开HIDL_FETCH的注释，就是passthrough，否则是Binderized方式，这里使用默认的Binderized方式。

3.开机启动服务

添加service.cpp文件； 

1
foo@bar:~$ vim vendor/realtek/common/ATV/hardware/interfaces/hello/1.0/default/service.cpp

内容如下： 

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
//service.cpp

#define LOG_TAG "vendor.realtek.hello@1.0-service"

#include <vendor/realtek/hello/1.0/IHello.h>
#include <hidl/HidlTransportSupport.h>

#include "Hello.h"

using android::hardware::configureRpcThreadpool;
using android::hardware::joinRpcThreadpool;
using vendor::realtek::hello::V1_0::IHello;
using vendor::realtek::hello::V1_0::implementation::Hello;
using android::sp;
using android::status_t;
using android::OK;

using namespace vendor::realtek::hello::V1_0;

int main() {
    // TODO: tune the max thread count.
    configureRpcThreadpool(10, true);
    sp<IHello> mHello = new Hello();
    status_t status = mHello->registerAsService();
    LOG_ALWAYS_FATAL_IF(status != OK, "Could not register IHello");
    ALOGD("IHello vendor.realtek.hello@1.0-service start\n");
    // other interface registration comes here
    joinRpcThreadpool();
    return 0;
}

添加vendor.realtek.hello@1.0-service.rc文件； 

1
foo@bar:~$ vim vendor/realtek/common/ATV/hardware/interfaces/hello/1.0/default/vendor.realtek.hello@1.0-service.rc

内容如下： 

1
2
3
4
5
//vendor.realtek.hello@1.0-service.rc
service hello-1-0 /vendor/bin/hw/vendor.realtek.hello@1.0-service
    class hal
    user system
    group system

修改Android.bp； 

1
foo@bar:~$ vim vendor/realtek/common/ATV/hardware/interfaces/hello/1.0/default/Android.bp

内容如下： 

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
//hello/1.0/default/Android.bp

// FIXME: your file license if you have one

cc_library_shared {
    // FIXME: this should only be -impl for a passthrough hal.
    // In most cases, to convert this to a binderized implementation, you should:
    // - change '-impl' to '-service' here and make it a cc_binary instead of a
    //   cc_library_shared.
    // - add a *.rc file for this module.
    // - delete HIDL_FETCH_I* functions.
    // - call configureRpcThreadpool and registerAsService on the instance.
    // You may also want to append '-impl/-service' with a specific identifier like
    // '-vendor' or '-<hardware identifier>' etc to distinguish it.
    name: "vendor.realtek.hello@1.0-impl",
    relative_install_path: "hw",
    // FIXME: this should be 'vendor: true' for modules that will eventually be
    // on AOSP.
    proprietary: true,
    srcs: [
        "Hello.cpp",
    ],
    shared_libs: [
        "libhidlbase",
	"libhidltransport",
	"libutils",
	"vendor.realtek.hello@1.0",
    ],
}

cc_binary {
    name: "vendor.realtek.hello@1.0-service",
    defaults: ["hidl_defaults"],
    proprietary: true,
    relative_install_path: "hw",
    srcs: [
        "Hello.cpp",
	"service.cpp"
    ],
    init_rc: ["vendor.realtek.hello@1.0-service.rc"],
    shared_libs: [
        "liblog",
	"libhidlbase",
	"libhidltransport",
	"libutils",
	"libcutils",
	"libbinder",
	"vendor.realtek.hello@1.0",
    ],
}

4.生成hal接口的Android.bp

看下update-makefiles.sh内容是什么： 

1
2
3
4
5
6
7
#!/bin/bash

source system/tools/hidl/update-makefiles-helper.sh

do_makefiles_update \
    "vendor.realtek:vendor/realtek/common/ATV/hardware/interfaces" \
    "android.hidl:system/libhidl/transport"

执行该脚本： 

1
foo@bar:~$ ./vendor/realtek/common/ATV/hardware/interfaces/update-makefiles.sh

1.0目录就生成了Android.bp文件。

2_update-makefiles.png

5.更新哈希值

编写genHash.sh 

1
2
3
foo@bar:~$ vim vendor/realtek/common/ATV/hardware/interfaces/hello/genHash.sh
foo@bar:~$ chmod u+x vendor/realtek/common/ATV/hardware/interfaces/hello/genHash.sh
foo@bar:~$ ./vendor/realtek/common/ATV/hardware/interfaces/hello/genHash.sh

内容如下： 

1
2
3
PACKAGE=vendor.realtek.hello@1.0::IHello

hidl-gen -L hash -rvendor.realtek:vendor/realtek/common/ATV/hardware/interfaces/ -randroid.hidl:system/libhidl/transport $PACKAGE

把输出的hash添加到current.txt 

1
foo@bar:~$ vim ./vendor/realtek/common/ATV/hardware/interfaces/current.txt

6.添加client测试

添加如下目录和文件： 

1
2
3
foo@bar:~$ mkdir -p vendor/realtek/common/ATV/hardware/interfaces/hello/1.0/vts/functional
foo@bar:~$ vim vendor/realtek/common/ATV/hardware/interfaces/hello/1.0/vts/functional/VtsHalHelloV1_0TargetTest.cpp
foo@bar:~$ vim vendor/realtek/common/ATV/hardware/interfaces/hello/1.0/vts/functional/Android.bp

以下是其内容： 

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
cc_test {
    name: "VtsHalHelloV1_0TargetTest",
    defaults: ["hidl_defaults"],
    srcs: ["VtsHalHelloV1_0TargetTest.cpp"],
    shared_libs: [
        "libbase",
	"libhidlbase",
	"liblog",
	"libutils",
	"vendor.realtek.hello@1.0",
    ],
    static_libs: ["VtsHalHidlTargetTestBase"],
    cflags: [
        "-O0",
	"-g",
    ]
}

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
//VtsHalHelloV1_0TargetTest.cpp

#define LOG_TAG "HelloHidlHalTest"

#include <VtsHalHidlTargetTestBase.h>
#include <android-base/logging.h>

#include <vendor/realtek/hello/1.0/IHello.h>

using vendor::realtek::hello::V1_0::IHello;
using ::android::hardware::hidl_string;
using ::android::hardware::hidl_vec;
using ::android::hardware::Return;
using ::android::hardware::Void;
using ::android::sp;

int main()
{
    int ret;

    sp<IHello> hello = IHello::getService();

    if(hello == nullptr) {
        ALOGD("Failed to get hello service\n");
	ret = -1;
    } else {
        hello->helloWorld("Hikari", [&](hidl_string result) {
	    ALOGD("%s\n",result.c_str());
	});
	ret = 0;
    }

    return ret;
}

7.添加hello目录的Android.bp

跑update-makefiles.sh的时候为啥没有生成这个？ 跟rtk代码makefile架构有关吗。

1
foo@bar:~$ vim vendor/realtek/common/ATV/hardware/interfaces/hello/Android.bp

内容如下： 

1
2
3
4
5
// This is an autogenerated file, do not edit.
subdirs = [
    "1.0",
    "1.0/vts/functional",
]

8.小编

hello最终文件架构如下：
3_end.png

小编试试添加的hello能不能编过： 

1
foo@bar:~$ mmm vendor/realtek/common/ATV/hardware/interfaces/hello/

9.注册hello并添加进编译

注册： 

1
foo@bar:~$ vim device/realtek/common/manifest.xml

添加内容如下： 

1
2
3
4
5
6
7
8
9
<hal format="hidl">
    <name>vendor.realtek.hello</name>
    <transport>hwbinder</transport>
    <version>1.0</version>
    <interface>
        <name>IHello</name>
	<instance>default</instance>
    </interface>
</hal>

编译： 

1
foo@bar:~$ vim device/realtek/common/product/rtk_base.mk

添加内容如下： 

1
2
3
4
PRODUCT_PACKAGES += \
    vendor.realtek.hello@1.0 \
    vendor.realtek.hello@1.0-impl \
    vendor.realtek.hello@1.0-impl \

10.添加seLinux规则

如果没有此步骤，开机之后vendor.realtek.hello@1.0-service会跑不起来。
修改file_contexts文件 

1
foo@bar:~$ vim device/realtek/common/sepolicy/file_contexts

补充如下：

1
/(vendor|system/vendor)/bin/hw/vendor\.realtek\.hello@1\.0-service        u:object_r:hal_hello_default_exec:s0

修改hwservice_contexts文件 

1
foo@bar:~$ vim device/realtek/common/sepolicy/hwservice_contexts

补充如下： 

1
vendor.realtek.hello::IHello        u:object_r:hal_hello_service:s0

修改hwservice.te文件 

1
foo@bar:~$ vim device/realtek/common/sepolicy/hwservice.te

补充如下： 

1
type hal_hello_service,   hwservice_manager_type;

添加hal_hello_default.te文件 

1
foo@bar:~$ vim device/realtek/common/sepolicy/hal_hello_default.te

内容如下： 

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
type hal_hello_default, domain;
type hal_hello_default_exec, exec_type, vendor_file_type, file_type;

init_daemon_domain(hal_hello_default);

hwbinder_use(hal_hello_default)
add_hwservice(hal_hello_default, hal_hello_service)


allow hal_hello_default hwservicemanager_prop:file r_file_perms;
allow hal_hello_default hwservicemanager:binder { transfer call };
allow hal_hello_default hal_hello_service:binder call;
allow hal_hello_default hal_hello_service:hwservice_manager { add find };
allow hal_hello_default hidl_base_hwservice:hwservice_manager add;

到此为止，开机之后服务依然有可能跑不起来，可以dmesg查看权限相关的avc报错，把相关的报错修掉之后，还有可能跑不起来，直接运行./vendor/bin/hw/vendor.realtek.hello@1.0-service，把avc denied修掉，应该就可以了。如果不确定是不是权限问题引起，可以先setenforce 0后直接运行服务，如果能跑起来，那么就是权限有问题。另外，客户端调用的时候如果看不到效果，可以先用client（参考第6点）调试。

11.全编代码验证

开机可以看到vendor.realtek.hello@1.0-service的log：

01-01 01:01:03.490 328 328 I ServiceManagement: Registered vendor.realtek.hello@1.0::IHello/default (start delay of 261ms)
01-01 01:01:03.491 328 328 I ServiceManagement: Removing namespace from process name vendor.realtek.hello@1.0-service to hello@1.0-service.
01-01 01:01:03.491 328 328 D vendor.realtek.hello@1.0-service: IHello vendor.realtek.hello@1.0-service start

在data/nativetest/VtsHalHelloV1_0TargetTest目录可以找到VtsHalHelloV1_0TargetTest文件，这个就是测试client，执行这个程序： 

1
foo@bar:~$ ./data/nativetest/VtsHalHelloV1_0TargetTest/VtsHalHelloV1_0TargetTest

可以看到：

08-04 10:06:24.211 2063 2063 D HelloHidlHalTest: Hello World, Hikari