Use docker as dev environment

regression/apps/network/udp_server.c

@@ -0,0 +1,63 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <unistd.h>
+
+#define SERVER_IP "127.0.0.1"
+#define SERVER_PORT 1234
+#define BUFFER_SIZE 1024
+
+int main() {
+    int sock_fd;
+    char buffer[BUFFER_SIZE];
+    struct sockaddr_in serv_addr;
+
+    // Create UDP socket
+    if ((sock_fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+        perror("socket creation failed");
+        exit(EXIT_FAILURE);
+    }
+
+    // Set server address
+    memset(&serv_addr, 0, sizeof(serv_addr));
+    serv_addr.sin_family = AF_INET;
+    serv_addr.sin_port = htons(SERVER_PORT);
+    if (inet_pton(AF_INET, SERVER_IP, &serv_addr.sin_addr) <= 0) {
+        perror("invalid IP address");
+        exit(EXIT_FAILURE);
+    }
+
+    // Bind to server address
+    if (bind(sock_fd, (struct sockaddr*)&serv_addr,
+             sizeof(serv_addr))
+        < 0) {
+        perror("bind failed");
+        exit(EXIT_FAILURE);
+    }
+
+    // Receive message from client
+    struct sockaddr_in sender_addr;
+    socklen_t sender_len = sizeof(sender_addr);
+    int recv_len;
+    if ((recv_len = recvfrom(sock_fd, buffer, BUFFER_SIZE, 0, (struct sockaddr *)&sender_addr, &sender_len)) < 0) {
+        perror("recvfrom failed");
+        exit(EXIT_FAILURE);
+    }
+    buffer[recv_len] = '\0';
+    printf("Received %s from %s:%d\n", buffer, inet_ntoa(sender_addr.sin_addr), ntohs(sender_addr.sin_port));
+
+    /// Send message to client
+    const char* message = "Hello world from udp server!";
+    if (sendto(sock_fd, message, strlen(message), 0, (const struct sockaddr *)&sender_addr, sizeof(sender_addr)) < 0) {
+        perror("sendto failed");
+        exit(EXIT_FAILURE);
+    }
+
+    // 关闭socket
+    close(sock_fd);
+
+    return 0;
+}