教程：适用于 Bazel，基于 FIDL 的绑定库

本教程适用于使用 SDK 并希望使用基于 FIDL 的驱动程序作者 自动生成的绑定库本教程假定您熟悉以下内容：

• FIDL 教程 - 生成的绑定库
• 为驱动程序创建新的绑定库

这两者的相同和不同之处是什么？

以上链接教程中列出的大部分概念和示例都适用于 提供给 SDK 用户

唯一的区别如下：

• 基于 FIDL 的绑定库 fuchsia_fidl_bind_library 的 Bazel 目标必须为 如果 FIDL 库不是来自 SDK，则手动添加。
• 绑定库代码生成目标 fuchsia_bind_cc_library 所需的 Bazel 目标 需要手动添加。

示例

本部分中的示例展示了一个手动定义的 FIDL 库，以及如何使用生成的 绑定库及其生成的关联代码，以便为子驱动程序创建绑定规则，以及 从父驱动程序访问这些绑定库值的常量。

BUILD.bazel

FIDL 库

# This is a FIDL library that we manually define.
fuchsia_fidl_library(
    name = "examples.gizmo",
    srcs = [
        "testfidl.fidl",
    ],
    library = "examples.gizmo",
)

# The C++ bindings for the FIDL library.
fuchsia_fidl_llcpp_library(
    name = "examples.gizmo_cc",
    library = ":examples.gizmo",
    visibility = ["//visibility:public"],
    deps = [
        "@fuchsia_sdk//pkg/fidl_cpp_v2",
        "@fuchsia_sdk//pkg/fidl_cpp_wire",
    ],
)

# We have to manually create the bind library from it.
fuchsia_fidl_bind_library(
    name = "examples.gizmo_bindlib",
    library = ":examples.gizmo",
    visibility = ["//visibility:public"],
)

# We have to manually create the C++ lib for the FIDL based bind library we created.
fuchsia_bind_cc_library(
    name = "examples.gizmo_bindlib_cc",
    library = ":examples.gizmo_bindlib",
    visibility = ["//visibility:public"],
)

家长驱动程序

fuchsia_cc_driver(
    name = "parent_driver",
    srcs = [
        "gizmo_server.h",
        "parent-driver.cc",
        "parent-driver.h",
    ],
    deps = [
        # This is a C++ lib from our manually created bind library.
        "//src/bind_library/lib:examples.gizmo.bind_cc",
        # This is a C++ lib from our manually created FIDL based bind library.
        "//src/bind_library/lib:examples.gizmo_bindlib_cc",
        "//src/bind_library/lib:examples.gizmo_cc",
        # This is a C++ lib from an SDK FIDL based bind library.
        "@fuchsia_sdk//fidl/fuchsia.device.fs:fuchsia.device.fs_bindlib_cc",
        "@fuchsia_sdk//pkg/driver_component_cpp",
    ],
)

子绑定规则

fuchsia_driver_bind_bytecode(
    name = "bind_bytecode",
    output = "child-driver.bindbc",
    rules = "child-driver.bind",
    deps = [
        # This bind library is one we created manually.
        "//src/bind_library/lib:examples.gizmo.bind",
        # This bind library is from a FIDL library that we created manually.
        "//src/bind_library/lib:examples.gizmo_bindlib",
        # This bind library is from an SDK FIDL library.
        "@fuchsia_sdk//fidl/fuchsia.device.fs:fuchsia.device.fs_bindlib",
    ],
)

parent-driver.cc

#include <bind/examples/gizmo/bind/cpp/bind.h>
#include <bind/examples/gizmo/cpp/bind.h>
#include <bind/fuchsia/device/fs/cpp/bind.h>

...

properties[4] = fdf::MakeProperty(arena, bind_fuchsia_device_fs::EXPORTER,
                                  bind_fuchsia_device_fs::EXPORTER_ZIRCONTRANSPORT);
properties[5] = fdf::MakeProperty(arena, bind_examples_gizmo::TESTINGPROTOCOL,
                                  bind_examples_gizmo::TESTINGPROTOCOL_ZIRCONTRANSPORT);

child-driver.bind

using fuchsia.device.fs;
using examples.gizmo;

...

fuchsia.device.fs.Exporter == fuchsia.device.fs.Exporter.ZirconTransport;
examples.gizmo.TestingProtocol == examples.gizmo.TestingProtocol.ZirconTransport;