Updated easysock files

easysock.c

@@ -77,13 +77,36 @@ int create_local (int network, char transport, char* address, int port,struct so
 
 int create_remote (int network,char transport,char* address,int port,struct sockaddr* remote_addr_struct) {
 
+	struct addrinfo hints;  /* Used to tell getaddrinfo what kind of address we want */
+	struct addrinfo* results; /* Used by getaddrinfo to store the addresses */
+
+
+	if (check_ip_ver(address) < 0) { /* If the address is a domain name */
+		int err_code;
+		char* port_str = malloc(10 * sizeof(char));
+
+		sprintf(port_str,"%d",port); /* getaddrinfo expects a string for its port */
+
+
+		memset(&hints,'\0',sizeof(hints));
+		hints.ai_socktype = char_to_socktype(transport);
+
+		err_code = getaddrinfo(address,port_str,&hints,&results);
+		if (err_code != 0) {
+			exit(err_code);
+		}
+		remote_addr_struct = results->ai_addr;
+		network = inet_to_int(results->ai_family);
+	} else {
+	        create_addr(network,address,port,remote_addr_struct);
+	}
 
 	int socket = create_socket(network,transport);
 	if (socket < 0) {
                 exit(errno);
         }
-        create_addr(network,address,port,remote_addr_struct);
-        int addrlen;
+
+       	int addrlen;
 	if (network == 4) {
 		addrlen = sizeof(struct sockaddr_in);
 	} else if (network == 6) {
@@ -102,3 +125,45 @@ int create_remote (int network,char transport,char* address,int port,struct sock
 	}
         return socket;
 }
+
+
+int check_ip_ver(char* address) {
+	char buffer[16]; /* 16 chars - 128 bits - is enough to hold an ipv6 address */
+	if (inet_pton(AF_INET,address,buffer) == 1) {
+		return 4;
+	} else if (inet_pton(AF_INET6,address,buffer) == 1) {
+		return 6;
+	} else {
+		return -1;
+	}
+}
+
+int int_to_inet(int network) {
+	if (network == 4) {
+		return AF_INET;
+	} else if (network == 6) {
+		return AF_INET6;
+	} else {
+		exit(207);
+	}
+}
+
+int inet_to_int(int af_type) {
+	if (af_type == AF_INET) {
+		return 4;
+	} else if (af_type == AF_INET6) {
+		return 6;
+	} else {
+		exit(207);
+	}
+}
+
+int char_to_socktype(char transport) {
+	if (transport == 'T') {
+		return SOCK_STREAM;
+	} else if (transport == 'U') {
+		return SOCK_DGRAM;
+	} else {
+		exit(250);
+	}
+}

easysock.h

@@ -2,7 +2,9 @@
 #define EASYSOCK_H_
 
 #include <string.h>
+#include <sys/types.h>
 #include <sys/socket.h>
+#include <netdb.h>
 #include <arpa/inet.h>
 #include <stdlib.h>
 #include <stdio.h>
@@ -50,5 +52,24 @@ It prints the error returned by 'connect' if something went wrong, and exits wit
 
 int create_remote (int network,char transport,char* address,int port,struct sockaddr* remote_addr_struct);
 
+/* check_ip_ver - This function checks if the given string is an IPv4 address (returns 4), 
+IPv6 address (returns 6) or neither (returns -1). */
+
+int check_ip_ver(char* address);
+
+/* int_to_inet - Takes an int value (4 for IPv4, 6 for IPv6) and returns AF_INET or
+AF_INET6 respectively. */
+
+int int_to_inet(int network);
+
+/* char_to_socktype - Takes a character that represents a transport-layer protocol
+(currently only supports 'T' for TCP or 'U' for UDP - exits with error code 250 if 
+the given characters is neither of these) and return the appropriate SOCKTYPE value. */
+
+int char_to_socktype(char transport);
+
+/* inet_to_int - Takes an int value that corresponds to AF_INET or AF_INET6,
+and returns the appropriate int value. */
+int inet_to_int(int af_type);
 
 #endif