ubus通信中 发布订阅模式的举例测试代码

好的，以下是一个简单的发布订阅模式的ubus通信测试代码，你可以参考一下：

服务端代码：

#include <libubox/uloop.h>
#include <libubus.h>

static struct ubus_context *ctx;

static void test_subscribe_handler(struct ubus_context *ctx,
                                    struct ubus_object *obj,
                                    struct ubus_request_data *req,
                                    const char *method,
                                    struct blob_attr *msg)
{
    const char *data = blobmsg_get_string(msg, "data");
    printf("Received data: %s\n", data);
}

static const struct ubus_method test_methods[] = {
    { .name = "subscribe", .handler = test_subscribe_handler },
};

static struct ubus_object_type test_object_type =
    UBUS_OBJECT_TYPE("test", test_methods);

static struct ubus_object test_object = {
    .name = "test",
    .type = &test_object_type,
    .methods = test_methods,
    .n_methods = ARRAY_SIZE(test_methods),
};

static void test_notify_handler(struct ubus_context *ctx,
                                struct ubus_subscriber *sub,
                                uint32_t id,
                                struct blob_attr *msg)
{
    const char *data = blobmsg_get_string(msg, "data");
    printf("Received data: %s\n", data);
}

int main(int argc, char **argv)
{
    ctx = ubus_connect(NULL);
    if (!ctx) {
        fprintf(stderr, "Failed to connect to ubus\n");
        return -1;
    }

    ubus_add_uloop(ctx);

    if (ubus_add_object(ctx, &test_object) != 0) {
        fprintf(stderr, "Failed to add ubus object\n");
        ubus_free(ctx);
        return -1;
    }

    struct ubus_subscriber subscriber;
    memset(&subscriber, 0, sizeof(subscriber));
    subscriber.cb = test_notify_handler;
    if (ubus_subscribe(ctx, &subscriber, "test.subscribe") != 0) {
        fprintf(stderr, "Failed to subscribe\n");
        ubus_free(ctx);
        return -1;
    }

    uloop_run();

    return 0;
}

客户端代码：

#include <libubox/uloop.h>
#include <libubus.h>

static struct ubus_context *ctx;

static void test_notify_handler(struct ubus_context *ctx,
                                struct ubus_subscriber *sub,
                                uint32_t id,
                                struct blob_attr *msg)
{
    const char *data = blobmsg_get_string(msg, "data");
    printf("Received data: %s\n", data);
}

int main(int argc, char **argv)
{
    ctx = ubus_connect(NULL);
    if (!ctx) {
        fprintf(stderr, "Failed to connect to ubus\n");
        return -1;
    }

    ubus_add_uloop(ctx);

    struct ubus_subscriber subscriber;
    memset(&subscriber, 0, sizeof(subscriber));
    subscriber.cb = test_notify_handler;
    if (ubus_subscribe(ctx, &subscriber, "test.subscribe") != 0) {
        fprintf(stderr, "Failed to subscribe\n");
        ubus_free(ctx);
        return -1;
    }

    struct blob_buf buf;
    blob_buf_init(&buf, 0);
    blobmsg_add_string(&buf, "data", "Hello, world!");
    if (ubus_notify(ctx, "test.subscribe", buf.head, 0, NULL) != 0) {
        fprintf(stderr, "Failed to send notification\n");
        ubus_free(ctx);
        return -1;
    }

    uloop_run();

    return 0;
}

这个例子中，服务端会创建一个ubus对象并添加到ubus上下文中，同时会添加一个订阅处理函数和一个订阅者。当客户端发送一个通知时，服务端订阅处理函数会被调用，并且订阅者也会收到通知。客户端会先订阅test.subscribe事件，然后发送一条带有"data"字段的通知。