lws_client_connect_via_info
时间: 2023-08-04 14:05:14 浏览: 84
lws_client_connect_via_info函数是libwebsockets库中的一个函数,用于通过提供的连接信息建立与服务器的连接。它接受一个lws_client_connect_info结构体作为参数,该结构体包含连接的详细信息,如服务器地址、端口号、协议等。通过调用这个函数,客户端可以使用提供的连接信息与服务器建立连接。
相关问题
#include <stdio.h> #include <string.h> #include <libwebsockets.h> #define BUFFER_SIZE 4096 static struct lws *wsi_client = NULL; static int callback_chat(struct lws *wsi, enum lws_callback_reasons reason, void *user, void *in, size_t len) { switch (reason) { case LWS_CALLBACK_CLIENT_ESTABLISHED: // 连接建立,记录wsi_client wsi_client = wsi; break; case LWS_CALLBACK_CLIENT_RECEIVE: // 接收到服务端发来的消息,输出到控制台 printf("[Client] Message received: %s\n", (char *)in); break; case LWS_CALLBACK_CLIENT_CLOSED: // 连接关闭,设置wsi_client为NULL wsi_client = NULL; break; default: break; } return 0; } static struct lws_protocols protocols[] = { { "chat", callback_chat, 0, BUFFER_SIZE }, { NULL, NULL, 0, 0 } }; int main(int argc, char **argv) { struct lws_context_creation_info info; memset(&info, 0, sizeof(info)); info.port = CONTEXT_PORT_NO_LISTEN; info.protocols = protocols; info.gid = -1; info.uid = -1; struct lws_context *context = lws_create_context(&info); if (context == NULL) { fprintf(stderr, "Error: Failed to create libwebsocket context\n"); return -1; } struct lws_client_connect_info connect_info; memset(&connect_info, 0, sizeof(connect_info)); connect_info.context = context; connect_info.address = "localhost"; connect_info.port = 8080; connect_info.path = "/"; connect_info.host = lws_canonical_hostname(context); connect_info.origin = connect_info.host; connect_info.protocol = protocols[0].name; struct lws *wsi = lws_client_connect_via_info(&connect_info); if (wsi == NULL) { fprintf(stderr, "Error: Failed to connect to server\n"); lws_context_destroy(context); return -1; } while (wsi_client == NULL) { lws_service(context, 50); } char buffer[BUFFER_SIZE]; while (fgets(buffer, BUFFER_SIZE, stdin)) { if (wsi_client == NULL) { break; } buffer[strlen(buffer) - 1] = '\0'; lws_write(wsi_client, (unsigned char *)buffer, strlen(buffer), LWS_WRITE_TEXT); } lws_context_destroy(context); return 0; }这段代码是否有问题?
这段代码似乎没有问题,它使用libwebsockets库创建了一个WebSocket客户端,连接到本地主机的端口8080上,并在控制台上显示接收到的消息。在main函数中,先创建一个libwebsocket的上下文,然后通过connect_info结构体配置WebSocket客户端连接信息,最后使用lws_client_connect_via_info函数连接WebSocket服务器。然后使用lws_service函数在while循环中等待连接建立,等到wsi_client不为空时,就可以向服务器发送消息了。在fgets函数中获取输入的消息,使用lws_write函数将消息发送给服务器。最后使用lws_context_destroy函数销毁libwebsockets上下文。
c websocket client thread
A C WebSocket client thread is a separate execution path that handles the communication between a client program written in C and a WebSocket server. The thread is responsible for establishing the WebSocket connection with the server, exchanging data with the server, and handling any errors or exceptions that may occur during the communication process.
The client thread typically consists of a loop that continuously listens for incoming messages from the server and processes them as they arrive. The thread may also be responsible for sending messages to the server on behalf of the client program.
To implement a C WebSocket client thread, you will need to use a WebSocket library that provides the necessary functions and data structures for establishing and managing WebSocket connections. Some popular C WebSocket libraries include libwebsockets, WebSocket++ and uWebSockets.
Here is an example of a simple C WebSocket client thread using the libwebsockets library:
```c
#include <libwebsockets.h>
void *websocket_client_thread(void *arg) {
struct lws_context_creation_info info = {0};
struct lws_context *ctx;
struct lws_client_connect_info ccinfo = {0};
struct lws *wsi;
char buf[1024];
int n, ret;
// Initialize libwebsockets context
info.port = CONTEXT_PORT_NO_LISTEN;
info.protocols = protocols;
ctx = lws_create_context(&info);
if (!ctx) {
printf("Error creating libwebsockets context\n");
return NULL;
}
// Set up connection parameters
ccinfo.context = ctx;
ccinfo.address = "localhost";
ccinfo.port = 8080;
ccinfo.path = "/";
ccinfo.host = lws_canonical_hostname(ctx);
ccinfo.origin = ccinfo.host;
ccinfo.protocol = protocols[0].name;
// Connect to server
wsi = lws_client_connect_via_info(&ccinfo);
if (!wsi) {
printf("Error connecting to server\n");
lws_context_destroy(ctx);
return NULL;
}
// Main loop
while (1) {
// Wait for incoming messages
ret = lws_service(ctx, 1000);
if (ret < 0) {
printf("Error servicing libwebsockets context\n");
break;
}
// Send message to server
strcpy(buf, "Hello, server!");
n = lws_write(wsi, (unsigned char *)buf, strlen(buf), LWS_WRITE_TEXT);
if (n < 0) {
printf("Error sending message to server\n");
break;
}
}
// Clean up
lws_context_destroy(ctx);
return NULL;
}
```
In this example, the client thread establishes a WebSocket connection with a server running on localhost:8080 and sends a message to the server once per second. The `lws_service` function waits for incoming messages from the server and handles them as they arrive. If an error occurs during the communication process, the thread exits and cleans up the libwebsockets context.