Project Finished

asyncproject/network_utils.c

@@ -0,0 +1,156 @@
+#include "network_utils.h"
+
+/* UDP Server code*/
+
+typedef struct thread_arg_pkg_ {
+
+    char ip_addr[16];
+    uint32_t port_no;
+    int comm_fd;
+    recv_fn_cb recv_fn;
+    pthread_t* thread;
+    char* recv_buffer;
+} thread_arg_pkg_t;
+
+
+static void*
+_udp_server_create_and_start(void* arg) {
+
+    thread_arg_pkg_t* thread_arg_pkg =
+        (thread_arg_pkg_t*)arg;
+
+    char ip_addr[16];
+    strncpy(ip_addr, thread_arg_pkg->ip_addr, 16);
+    uint32_t port_no = thread_arg_pkg->port_no;
+    recv_fn_cb recv_fn = thread_arg_pkg->recv_fn;
+    free(thread_arg_pkg);
+    thread_arg_pkg = NULL;
+
+    int udp_sock_fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+
+    if (udp_sock_fd == -1) {
+        printf("Socket Creation Failed\n");
+        return 0;
+    }
+
+    struct sockaddr_in server_addr;
+    server_addr.sin_family = AF_INET;
+    server_addr.sin_port = port_no;
+    server_addr.sin_addr.s_addr = INADDR_ANY;
+
+    if (bind(udp_sock_fd, (struct sockaddr*)&server_addr,
+        sizeof(struct sockaddr)) == -1) {
+        printf("Error : UDP socket bind failed\n");
+        return 0;
+    }
+
+    char* recv_buffer = calloc(1, MAX_PACKET_BUFFER_SIZE);
+
+    fd_set active_sock_fd_set,
+        backup_sock_fd_set;
+
+    FD_ZERO(&active_sock_fd_set);
+    FD_ZERO(&backup_sock_fd_set);
+
+    struct sockaddr_in client_addr;
+    FD_SET(udp_sock_fd, &backup_sock_fd_set);
+    int bytes_recvd = 0,
+        addr_len = sizeof(client_addr);
+
+    while (1) {
+
+        memcpy(&active_sock_fd_set, &backup_sock_fd_set, sizeof(fd_set));
+        select(udp_sock_fd + 1, &active_sock_fd_set, NULL, NULL, NULL);
+
+        if (FD_ISSET(udp_sock_fd, &active_sock_fd_set)) {
+
+            memset(recv_buffer, 0, MAX_PACKET_BUFFER_SIZE);
+            bytes_recvd = recvfrom(udp_sock_fd, recv_buffer,
+                MAX_PACKET_BUFFER_SIZE, 0,
+                (struct sockaddr*)&client_addr, &addr_len);
+
+            recv_fn(recv_buffer, bytes_recvd,
+                network_covert_ip_n_to_p(
+                    (uint32_t)htonl(client_addr.sin_addr.s_addr), 0),
+                client_addr.sin_port, udp_sock_fd);
+        }
+    }
+    return 0;
+}
+
+
+void
+udp_server_create_and_start(
+    char* ip_addr,
+    uint32_t udp_port_no,
+    recv_fn_cb recv_fn) {
+
+    pthread_attr_t attr;
+    pthread_t recv_pkt_thread;
+    thread_arg_pkg_t* thread_arg_pkg;
+
+    pthread_attr_init(&attr);
+    pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
+
+    thread_arg_pkg = calloc(1, sizeof(thread_arg_pkg_t));
+    strncpy(thread_arg_pkg->ip_addr, ip_addr, 16);
+    thread_arg_pkg->port_no = udp_port_no;
+    thread_arg_pkg->recv_fn = recv_fn;
+
+    pthread_create(&recv_pkt_thread, &attr,
+        _udp_server_create_and_start,
+        (void*)thread_arg_pkg);
+}
+
+int
+send_udp_msg(char* dest_ip_addr,
+    uint32_t dest_port_no,
+    char* msg,
+    uint32_t msg_size,
+    int sock_fd) {
+
+    struct sockaddr_in dest;
+
+    dest.sin_family = AF_INET;
+    dest.sin_port = dest_port_no;
+    struct hostent* host = (struct hostent*)gethostbyname(dest_ip_addr);
+    dest.sin_addr = *((struct in_addr*)host->h_addr_list);
+    int addr_len = sizeof(struct sockaddr);
+
+    if (sock_fd < 0) {
+
+        sock_fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+
+        if (sock_fd < 0) {
+            printf("socket creation failed, errno = %d\n", errno);
+            return -1;
+        }
+    }
+    sendto(sock_fd, msg, msg_size,
+        0, (struct sockaddr*)&dest,
+        sizeof(struct sockaddr));
+    return sock_fd;
+}
+
+char*
+network_covert_ip_n_to_p(uint32_t ip_addr,
+    char* output_buffer) {
+
+    char* out = NULL;
+    static char str_ip[16];
+    out = !output_buffer ? str_ip : output_buffer;
+    memset(out, 0, 16);
+    ip_addr = htonl(ip_addr);
+    inet_ntop(AF_INET, &ip_addr, out, 16);
+    out[15] = '\0';
+    return out;
+}
+
+uint32_t
+network_covert_ip_p_to_n(char* ip_addr) {
+
+    uint32_t binary_prefix = 0;
+    inet_pton(AF_INET, ip_addr, &binary_prefix);
+    binary_prefix = htonl(binary_prefix);
+    return binary_prefix;
+}