Test UDP echo

Author: karthik-d

Check/UDP/Client

@@ -0,0 +1,38 @@
+#include<stdio.h>
+#include<stdlib.h>
+
+#include<arpa/inet.h>
+#include<sys/socket.h>
+#include<sys/types.h>
+#include<netdb.h>
+#include<unistd.h>
+#include<fcntl.h>
+
+void main(){
+    int sock_fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+
+    struct sockaddr_in serv_addr;
+    serv_addr.sin_family = AF_INET;
+    serv_addr.sin_port = htons(8080);
+    serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
+    int serv_addr_size = sizeof(serv_addr);
+
+    int msg_size = -1;
+    char* msg_buff = (char*)malloc(sizeof(char)*100);
+    do{
+        printf("\nEnter Message UDP: ");
+        scanf(" %s", msg_buff);
+        printf("\n MSG: %s", msg_buff);  
+        fflush(stdout);
+        msg_size = sendto(sock_fd, msg_buff, 100, MSG_CONFIRM, (struct sockaddr*)&serv_addr, serv_addr_size);
+        printf("\nHERE: %d", msg_size);   
+        fflush(stdout);
+        msg_size = recvfrom(sock_fd, msg_buff, 100, MSG_WAITALL, (struct sockaddr*)&serv_addr, &serv_addr_size);   
+        printf("\nRECVD: %s", msg_buff);   
+        fflush(stdout);
+        printf("\nAGAIN ");   
+        fflush(stdout);
+    }while(msg_size!=0);
+
+    printf("\nEXITED...");
+}

Check/UDP/Server

@@ -0,0 +1,99 @@
+#include<stdio.h>
+#include<stdlib.h>
+
+#include<arpa/inet.h>
+#include<sys/socket.h>
+#include<sys/types.h>
+#include<netdb.h>
+#include<unistd.h>
+#include<fcntl.h>
+
+void main(){
+    int sock_fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+    int true_flag = 1;
+    setsockopt(sock_fd, SOL_SOCKET, SO_REUSEADDR, &true_flag, sizeof(int));
+
+    struct sockaddr_in bind_addr;
+    bind_addr.sin_family = AF_INET;
+    bind_addr.sin_port = htons(8080);
+    bind_addr.sin_addr.s_addr = htonl(INADDR_ANY);
+    bind(sock_fd, (struct sockaddr*)&bind_addr, sizeof(bind_addr));
+
+    struct sockaddr_in client_addr;
+    int client_addr_size;
+
+    char *client_ip = (char*)malloc(sizeof(char)*100);
+    int client_port;
+
+    int msg_size = -1;
+    char* msg_buff = (char*)malloc(sizeof(char)*100);
+    do{
+        msg_size = recvfrom(sock_fd, msg_buff, 100, MSG_WAITALL, (struct sockaddr*)&client_addr, &client_addr_size);   
+        client_port = ntohs(client_addr.sin_port);
+        inet_ntop(AF_INET, (void*)&client_addr.sin_addr, client_ip, 100);
+        printf("\nFrom %s:%d", client_ip, client_port);  
+        printf("\n%s", msg_buff); 
+        fflush(stdout);    
+        msg_size = sendto(sock_fd, "CHECK", 6, MSG_CONFIRM, (struct sockaddr*)&client_addr, client_addr_size);     
+        printf("DONE");
+        fflush(stdout);
+    }while(msg_size!=0);
+}
+
+/*
+
+sendto(sockfd, (const char *)hello, strlen(hello),
+		MSG_CONFIRM, (const struct sockaddr *) &cliaddr,
+			len);
+	printf("Hello message sent.\n");
+
+#define PORT	 8080
+#define MAXLINE 1024
+
+// Driver code
+int main() {
+	int sockfd;
+	char buffer[MAXLINE];
+	char *hello = "Hello from server";
+	struct sockaddr_in servaddr, cliaddr;
+	
+	// Creating socket file descriptor
+	if ( (sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0 ) {
+		perror("socket creation failed");
+		exit(EXIT_FAILURE);
+	}
+	
+	memset(&servaddr, 0, sizeof(servaddr));
+	memset(&cliaddr, 0, sizeof(cliaddr));
+	
+	// Filling server information
+	servaddr.sin_family = AF_INET; // IPv4
+	servaddr.sin_addr.s_addr = INADDR_ANY;
+	servaddr.sin_port = htons(PORT);
+	
+	// Bind the socket with the server address
+	if ( bind(sockfd, (const struct sockaddr *)&servaddr,
+			sizeof(servaddr)) < 0 )
+	{
+		perror("bind failed");
+		exit(EXIT_FAILURE);
+	}
+	
+	int len, n;
+
+	len = sizeof(cliaddr); //len is value/resuslt
+
+	n = recvfrom(sockfd, (char *)buffer, MAXLINE,
+				MSG_WAITALL, ( struct sockaddr *) &cliaddr,
+				&len);
+	buffer[n] = '\0';
+	printf("Client : %s\n", buffer);
+	sendto(sockfd, (const char *)hello, strlen(hello),
+		MSG_CONFIRM, (const struct sockaddr *) &cliaddr,
+			len);
+	printf("Hello message sent.\n");
+	
+	return 0;
+}
+
+*/