4 files changed, 252 insertions, 0 deletions

diff --git a/q5/client.c b/q5/client.c
new file mode 100644
index 0000000..7219476
--- /dev/null
+++ b/q5/client.c
@@ -0,0 +1,47 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <unistd.h>
+#include <string.h>
+#include <arpa/inet.h>
+#include <string.h>
+
+int main(int argc, char* argv[]) { 
+    const char *server_name = "127.0.0.1";
+    int sockfd, connfd; 
+    struct sockaddr_in servaddr, cli; 
+
+    sockfd = socket(AF_INET, SOCK_STREAM, 0); 
+    servaddr.sin_family = AF_INET; 
+    inet_pton(AF_INET, server_name, &servaddr.sin_addr);
+
+    int port = atoi(argv[1]);
+    servaddr.sin_port = htons(port);
+
+    if((connect(sockfd, (struct sockaddr*)&servaddr, sizeof(servaddr))) == 0) {
+        printf("Connected to server!\n");
+        fflush(stdout);
+    } else {
+        printf("Invalid or busy server address\n");
+        fflush(stdout);
+        exit(0);
+    };
+
+    int cont = 0;
+    char *buf = malloc(1024);
+    printf("Client input: ");
+    fgets(buf, 100, stdin);
+    while(strcmp(buf, "quit\n") != 0) {
+        send(sockfd, buf, 100, 0);
+        if ((cont = recv(sockfd, buf, 100, 0)) > 0) {
+            printf("Server response: %s\n", buf);;
+            fflush(stdout);
+        }
+        printf("Client input: ");
+        fgets(buf, 100, stdin);
+    };
+
+    close(sockfd); 
+}
diff --git a/q5/server.c b/q5/server.c
new file mode 100644
index 0000000..87870bb
--- /dev/null
+++ b/q5/server.c
@@ -0,0 +1,86 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <unistd.h>
+#include <string.h>
+#include <arpa/inet.h>
+#include <pthread.h>
+
+void* handle_client(void *);
+
+int client_list[16];
+int client_list_len;
+
+int main(int argc, char *argv[]) {
+    int sockfd, connfd; 
+
+    pthread_mutex_t list_lock;
+    pthread_mutex_init(&list_lock, NULL);
+
+    struct sockaddr_in servaddr, cli; 
+  
+    sockfd = socket(AF_INET, SOCK_STREAM, 0); 
+    servaddr.sin_family = AF_INET; 
+    servaddr.sin_addr.s_addr = htonl(INADDR_ANY); 
+
+    int port = atoi(argv[1]);
+    servaddr.sin_port = htons(port);
+  
+    bind(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr));
+  
+    listen(sockfd, 128);
+    printf("Server started at %s...\n", inet_ntoa(servaddr.sin_addr));
+    fflush(stdout);
+
+    while(1) {
+        socklen_t len = sizeof(cli);
+        connfd = accept(sockfd, (struct sockaddr *)&cli, &len);
+        int i = getpeername(connfd, (struct sockaddr*)&cli, &len);
+
+        pthread_mutex_lock(&list_lock);
+        client_list[client_list_len] = connfd;
+        client_list_len += 1;
+        pthread_mutex_unlock(&list_lock);
+
+        int n;
+        char buf[100];
+
+        // if((pid=fork())==0){
+        //     close(sockfd);
+        //     while((n = recv(connfd, buf, 100, 0)) > 0) {
+        //         printf("Client message: %s\n", buf);
+        //         fflush(stdout);
+        //         for (int i = 0; i < client_list_len; i++) {
+        //             int curr_conn = client_list[i];
+        //             if (i != connfd) {
+        //                 send(i, buf, n, 0);
+        //             }
+        //         }
+        //     };
+        //     exit(0);
+        // }
+
+        pthread_t client_thread;
+        pthread_create(&client_thread, NULL, &handle_client, &connfd);
+    }
+    return 0;
+}
+
+void* handle_client(void* param) {
+    int *connfd = (int *) param;
+    int n;
+    char buf[100];
+    while ((n = recv(*connfd, buf, 100, 0)) > 0) {
+        printf("Client message (%d): %s", *connfd, buf);
+        fflush(stdout);
+        for (int i = 0; i < client_list_len; i++) {
+            int curr_conn = *(client_list + i);
+            if (curr_conn != *connfd) {
+                send(curr_conn, buf, n, 0);
+            }
+        }
+    }
+    return 0;
+}
diff --git a/q5/with-threads/client.c b/q5/with-threads/client.c
new file mode 100644
index 0000000..7219476
--- /dev/null
+++ b/q5/with-threads/client.c
@@ -0,0 +1,47 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <unistd.h>
+#include <string.h>
+#include <arpa/inet.h>
+#include <string.h>
+
+int main(int argc, char* argv[]) { 
+    const char *server_name = "127.0.0.1";
+    int sockfd, connfd; 
+    struct sockaddr_in servaddr, cli; 
+
+    sockfd = socket(AF_INET, SOCK_STREAM, 0); 
+    servaddr.sin_family = AF_INET; 
+    inet_pton(AF_INET, server_name, &servaddr.sin_addr);
+
+    int port = atoi(argv[1]);
+    servaddr.sin_port = htons(port);
+
+    if((connect(sockfd, (struct sockaddr*)&servaddr, sizeof(servaddr))) == 0) {
+        printf("Connected to server!\n");
+        fflush(stdout);
+    } else {
+        printf("Invalid or busy server address\n");
+        fflush(stdout);
+        exit(0);
+    };
+
+    int cont = 0;
+    char *buf = malloc(1024);
+    printf("Client input: ");
+    fgets(buf, 100, stdin);
+    while(strcmp(buf, "quit\n") != 0) {
+        send(sockfd, buf, 100, 0);
+        if ((cont = recv(sockfd, buf, 100, 0)) > 0) {
+            printf("Server response: %s\n", buf);;
+            fflush(stdout);
+        }
+        printf("Client input: ");
+        fgets(buf, 100, stdin);
+    };
+
+    close(sockfd); 
+}
diff --git a/q5/with-threads/server.c b/q5/with-threads/server.c
new file mode 100644
index 0000000..c2d5c56
--- /dev/null
+++ b/q5/with-threads/server.c
@@ -0,0 +1,72 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <unistd.h>
+#include <string.h>
+#include <arpa/inet.h>
+#include <pthread.h>
+
+void* handle_client(void *);
+
+int client_list[16];
+int client_list_len;
+
+int main(int argc, char *argv[]) {
+    int sockfd;
+
+    pthread_mutex_t list_lock;
+    pthread_mutex_init(&list_lock, NULL);
+
+    struct sockaddr_in servaddr, cli; 
+  
+    sockfd = socket(AF_INET, SOCK_STREAM, 0); 
+    servaddr.sin_family = AF_INET; 
+    servaddr.sin_addr.s_addr = htonl(INADDR_ANY); 
+
+    int port = atoi(argv[1]);
+    servaddr.sin_port = htons(port);
+  
+    bind(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr));
+  
+    listen(sockfd, 128);
+    printf("Server started at %s...\n", inet_ntoa(servaddr.sin_addr));
+    fflush(stdout);
+
+    while(1) {
+        socklen_t len = sizeof(cli);
+        int connfd = accept(sockfd, (struct sockaddr*)&cli, &len);
+        int i = getpeername(connfd, (struct sockaddr*)&cli, &len);
+
+        client_list[client_list_len] = connfd;
+        client_list_len += 1;
+
+        printf("Clients connected: %d \nDescriptors: ", client_list_len);
+        for(int i = 0; i < client_list_len; i++) {
+            printf("%d ", client_list[i]);
+        }
+        printf("\n");
+        fflush(stdout);
+
+        pthread_t client_thread;
+        pthread_create(&client_thread, NULL, &handle_client, &connfd);
+    }
+    close(sockfd);
+    return 0;
+}
+
+void* handle_client(void* param) {
+    int *connfd = (int *) param;
+    int n;
+    char buf[100];
+    bzero(&buf, 100);
+    while ((n = recv(*connfd, buf, 100, 0)) > 0) {
+        printf("Client message (%d): %s", *connfd, buf);
+        fflush(stdout);
+        send(*connfd, buf, n, 0);
+        bzero(&buf, 100);
+    }
+    close(*connfd);
+    return 0;
+}