return std::make_shared<message>(std::move(topic), std::move(payload), DFLT_QOS, DFLT_RETAINED);
时间: 2024-05-17 20:10:33 浏览: 172
这是一段C++代码,使用了智能指针和移动语义,创建了一个消息对象并返回它。具体来说,它使用了std::make_shared函数来创建一个std::shared_ptr对象,其中这个std::shared_ptr对象包装了一个message对象,该message对象被用给定的参数构造出来。其中,std::move函数将参数的所有权从当前对象移动到新创建的message对象中。最后,该std::shared_ptr对象被返回。
简单来说,这段代码是用于创建一个消息对象并返回其智能指针的。其中包含了topic、payload、DFLT_QOS和DFLT_RETAINED四个参数,这些参数用于初始化message对象。返回的智能指针可以确保message对象在不再需要时被正确地释放掉。
相关问题:
1. 什么是智能指针?
2. 什么是移动语义?
3. 如何使用std::make_shared函数创建智能指针?
4. message类中DFLT_QOS和DFLT_RETAINED有什么作用?
相关问题
帮我修改代码,实现用wss发送serialized_data到wss://autopilot-test.t3go.cn:443/api/v1/vehicle/push/message/LFB1FV696M2L43840。 main.cpp: #include "ros/ros.h" #include "std_msgs/String.h" #include <boost/thread/locks.hpp> #include <boost/thread/shared_mutex.hpp> #include "third_party/apollo/proto/perception/perception_obstacle.pb.h" #include "t3_perception.pb.h" apollo::perception::PerceptionObstacles perception_obstacles_; void perceptionCallback(const std_msgs::String& msg) { ROS_WARN("t3 perceptionCallback parse"); if (perception_obstacles_.ParseFromString(msg.data)) { double timestamp = perception_obstacles_.header().timestamp_sec(); ROS_INFO("t3 perceptionCallback timestamp %f count:%d", timestamp, perception_obstacles_.perception_obstacle().size()); std::string data; perception_obstacles_.SerializeToString(&data); VehData veh_data; veh_data.set_messagetype(5); veh_data.set_messagedes("PerceptionObstacles"); veh_data.set_contents(data); std::string serialized_data; veh_data.SerializeToString(&serialized_data); } else { ROS_ERROR("t3 perceptionCallback parse fail!"); } } int main(int argc, char **argv) { ros::init(argc, argv, "listener"); ros::NodeHandle n; ros::Subscriber sub = n.subscribe("/perception_node/perception_objects", 1000, perceptionCallback); ros::spin(); return 0; } t3_perception.proto: syntax = "proto3"; option java_package = "com.t3.ts.dt.ad.web.protobuf"; option java_outer_classname = "VehDTO"; option java_multiple_files = false; message VehData { /** messageType: 1:客户端心跳 2:云端心跳响应 3:连接成功 4:连接失败 5:客户端发送消息 6:云端发送消息 7:消息处理成功 8:消息处理失败 9:此客户端未注册 10:未知消息类型 */ int32 messageType = 1; string messageDes = 2; bytes contents = 3; // 发送内容 }
您可以使用以下代码实现发送 `serialized_data` 到 `wss://autopilot-test.t3go.cn:443/api/v1/vehicle/push/message/LFB1FV696M2L43840`:
```cpp
#include "ros/ros.h"
#include "std_msgs/String.h"
#include <boost/thread/locks.hpp>
#include <boost/thread/shared_mutex.hpp>
#include "third_party/apollo/proto/perception/perception_obstacle.pb.h"
#include "t3_perception.pb.h"
#include "websocketpp/config/asio_client.hpp"
#include "websocketpp/client.hpp"
using websocketpp::lib::placeholders::_1;
using websocketpp::lib::placeholders::_2;
using websocketpp::lib::bind;
typedef websocketpp::client<websocketpp::config::asio_tls_client> client;
typedef boost::shared_ptr<boost::asio::ssl::context> context_ptr;
context_ptr on_tls_init(websocketpp::connection_hdl) {
context_ptr ctx = boost::make_shared<boost::asio::ssl::context>(boost::asio::ssl::context::tlsv12);
try {
ctx->set_options(boost::asio::ssl::context::default_workarounds |
boost::asio::ssl::context::no_sslv2 |
boost::asio::ssl::context::no_sslv3 |
boost::asio::ssl::context::single_dh_use);
} catch (std::exception& e) {
std::cout << e.what() << std::endl;
}
return ctx;
}
void on_open(client* c, websocketpp::connection_hdl hdl) {
std::string message = "Hello, world!";
try {
c->send(hdl, message, websocketpp::frame::opcode::text);
} catch (websocketpp::exception const & e) {
std::cout << e.what() << std::endl;
}
}
void on_fail(client* c, websocketpp::connection_hdl hdl) {
client::connection_ptr con = c->get_con_from_hdl(hdl);
std::cout << "Connection to " << con->get_uri() << " failed: " << con->get_ec().message() << std::endl;
}
void on_message(websocketpp::connection_hdl hdl, client::message_ptr msg) {
std::cout << "Received message: " << msg->get_payload() << std::endl;
}
void perceptionCallback(const std_msgs::String& msg) {
ROS_WARN("t3 perceptionCallback parse");
apollo::perception::PerceptionObstacles perception_obstacles_;
if (perception_obstacles_.ParseFromString(msg.data)) {
double timestamp = perception_obstacles_.header().timestamp_sec();
ROS_INFO("t3 perceptionCallback timestamp %f count:%d", timestamp, perception_obstacles_.perception_obstacle().size());
std::string data;
perception_obstacles_.SerializeToString(&data);
VehData veh_data;
veh_data.set_messagetype(5);
veh_data.set_messagedes("PerceptionObstacles");
veh_data.set_contents(data);
std::string serialized_data;
veh_data.SerializeToString(&serialized_data);
// 创建 websocket 客户端
client c;
std::string uri = "wss://autopilot-test.t3go.cn:443/api/v1/vehicle/push/message/LFB1FV696M2L43840";
try {
// 设置 TLS 初始化回调函数
c.set_tls_init_handler(bind(&on_tls_init, ::_1));
// 设置回调函数
c.set_open_handler(bind(&on_open, &c, ::_1));
c.set_fail_handler(bind(&on_fail, &c, ::_1));
c.set_message_handler(bind(&on_message, ::_1, ::_2));
// 连接服务器
websocketpp::lib::error_code ec;
client::connection_ptr con = c.get_connection(uri, ec);
if (ec) {
std::cout << "Could not create connection: " << ec.message() << std::endl;
return;
}
c.connect(con);
// 发送数据
c.send(con->get_handle(), serialized_data, websocketpp::frame::opcode::binary);
// 等待连接关闭
c.run();
} catch (websocketpp::exception const & e) {
std::cout << e.what() << std::endl;
}
} else {
ROS_ERROR("t3 perceptionCallback parse fail!");
}
}
int main(int argc, char **argv) {
ros::init(argc, argv, "listener");
ros::NodeHandle n;
ros::Subscriber sub = n.subscribe("/perception_node/perception_objects", 1000, perceptionCallback);
ros::spin();
return 0;
}
```
在上面的代码中,我们使用了 websocketpp 库来创建 websocket 客户端,并发送二进制数据到指定的服务器。在 `perceptionCallback` 函数中,我们将解析得到的 Protobuf 数据序列化为二进制数据,并发送到服务器。
请注意,这里我们使用了 TLS 加密的 websocket 连接,因此需要设置 TLS 初始化回调函数来初始化 SSL 上下文。同时,我们也设置了连接成功、连接失败和收到消息的回调函数。
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