init repo

main.c

@@ -0,0 +1,95 @@
+#include <errno.h>
+#include <netdb.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <string.h>
+#include <unistd.h>
+
+int extract_message(char **buf, char **msg)
+{
+	char	*newbuf;
+	int	i;
+
+	*msg = 0;
+	if (*buf == 0)
+		return (0);
+	i = 0;
+	while ((*buf)[i])
+	{
+		if ((*buf)[i] == '\n')
+		{
+			newbuf = calloc(1, sizeof(*newbuf) * (strlen(*buf + i + 1) + 1));
+			if (newbuf == 0)
+				return (-1);
+			strcpy(newbuf, *buf + i + 1);
+			*msg = *buf;
+			(*msg)[i + 1] = 0;
+			*buf = newbuf;
+			return (1);
+		}
+		i++;
+	}
+	return (0);
+}
+
+char *str_join(char *buf, char *add)
+{
+	char	*newbuf;
+	int		len;
+
+	if (buf == 0)
+		len = 0;
+	else
+		len = strlen(buf);
+	newbuf = malloc(sizeof(*newbuf) * (len + strlen(add) + 1));
+	if (newbuf == 0)
+		return (0);
+	newbuf[0] = 0;
+	if (buf != 0)
+		strcat(newbuf, buf);
+	free(buf);
+	strcat(newbuf, add);
+	return (newbuf);
+}
+
+
+int main() {
+	int sockfd, connfd, len;
+	struct sockaddr_in servaddr, cli; 
+
+	// socket create and verification 
+	sockfd = socket(AF_INET, SOCK_STREAM, 0); 
+	if (sockfd == -1) { 
+		printf("socket creation failed...\n"); 
+		exit(0); 
+	} 
+	else
+		printf("Socket successfully created..\n"); 
+	bzero(&servaddr, sizeof(servaddr)); 
+
+	// assign IP, PORT 
+	servaddr.sin_family = AF_INET; 
+	servaddr.sin_addr.s_addr = htonl(2130706433); //127.0.0.1
+	servaddr.sin_port = htons(8081); 
+
+	// Binding newly created socket to given IP and verification 
+	if ((bind(sockfd, (const struct sockaddr *)&servaddr, sizeof(servaddr))) != 0) { 
+		printf("socket bind failed...\n"); 
+		exit(0); 
+	} 
+	else
+		printf("Socket successfully binded..\n");
+	if (listen(sockfd, 10) != 0) {
+		printf("cannot listen\n"); 
+		exit(0); 
+	}
+	len = sizeof(cli);
+	connfd = accept(sockfd, (struct sockaddr *)&cli, &len);
+	if (connfd < 0) { 
+		printf("server acccept failed...\n"); 
+		exit(0);
+	} 
+	else
+		printf("server acccept the client...\n");
+}
+

mini_serv.c

@@ -0,0 +1,64 @@
+
+// write
+// close
+// select
+// socket
+// accept
+// listen
+// send
+// recv
+// bind
+// strstr
+// malloc
+// realloc
+// free
+// calloc
+// bzero
+// atoi
+// sprintf
+// strlen
+// exit
+// strcpy
+// strcat
+// memset
+
+
+int main() {
+	int sockfd, connfd, len;
+	struct sockaddr_in servaddr, cli; 
+
+	// socket create and verification 
+	sockfd = socket(AF_INET, SOCK_STREAM, 0); 
+	if (sockfd == -1) { 
+		printf("socket creation failed...\n"); 
+		exit(0); 
+	} 
+	else
+		printf("Socket successfully created..\n"); 
+	bzero(&servaddr, sizeof(servaddr)); 
+
+	// assign IP, PORT 
+	servaddr.sin_family = AF_INET; 
+	servaddr.sin_addr.s_addr = htonl(2130706433); //127.0.0.1
+	servaddr.sin_port = htons(8081); 
+
+	// Binding newly created socket to given IP and verification 
+	if ((bind(sockfd, (const struct sockaddr *)&servaddr, sizeof(servaddr))) != 0) { 
+		printf("socket bind failed...\n"); 
+		exit(0); 
+	} 
+	else
+		printf("Socket successfully binded..\n");
+	if (listen(sockfd, 10) != 0) {
+		printf("cannot listen\n"); 
+		exit(0); 
+	}
+	len = sizeof(cli);
+	connfd = accept(sockfd, (struct sockaddr *)&cli, &len);
+	if (connfd < 0) { 
+		printf("server acccept failed...\n"); 
+		exit(0);
+	} 
+	else
+		printf("server acccept the client...\n");
+}

mini_serv_ex.c

@@ -0,0 +1,79 @@
+#include <string.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <sys/select.h>
+
+typedef int bool;
+
+bool	check_arguments(int argc)
+{
+	return (argc > 1);
+}
+
+void	putstr_fd(char *str, int fd)
+{
+	write(fd, str, strlen(str));
+}
+
+void	arguments_error(void)
+{
+	putstr_fd("Wrong number of arguments\n", 2);
+	exit(1);
+}
+
+void	fatal_error(void)
+{
+	putstr_fd("Fatal error\n", 2);
+	exit(1);
+}
+
+int get_port(char *arg)
+{
+	int	port = atoi(arg);
+	return (port);
+}
+
+int	main(int argc, char **argv)
+{
+	int						port;
+	int						server_fd;
+	int						client_fd;
+	char					buf[1024];
+	struct sockaddr_in		addr;
+	socklen_t 				addr_len;
+	fd_set					fds;
+
+	server_fd = socket(AF_INET, SOCK_STREAM, 0);
+	addr.sin_family = AF_INET;
+	addr.sin_port = htons(port);
+	addr.sin_addr.s_addr = htonl(INADDR_ANY);
+	addr_len = sizeof(addr);
+
+	if (!check_arguments(argc))
+		arguments_error();
+	if ((port = get_port(argv[1])) == -1)
+		fatal_error();
+	printf("port = %d\n", port);
+	if (bind(server_fd, (struct sockaddr *)&addr, addr_len)== -1)
+		fatal_error();
+	if (listen(server_fd, 0) == -1)
+		fatal_error();
+	while (1)
+	{
+		if ((client_fd = accept(server_fd, (struct sockaddr *)&addr, &addr_len)) == -1)
+			fatal_error();
+		FD_ZERO(&fds);
+		FD_SET(client_fd, &fds);
+		select(client_fd + 1, &fds, NULL, NULL, NULL);
+		if (FD_ISSET(client_fd, &fds))
+		{
+			recv(client_fd, buf, 1024, 0);
+			printf("Recv: %s\n", buf);
+		}
+	}
+	return (0);
+}

server.py

@@ -0,0 +1,22 @@
+
+import socket
+
+host = 'localhost'
+port = 9999
+address = (host, port)
+
+server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+server_socket.bind((address))
+server_socket.listen(5)
+print ("Listening for client . . .")
+conn, address = server_socket.accept()
+print ("Connected to client at ", address)
+while True:
+	try:
+		output = conn.recv(2048)
+		if output:
+			print ("Message received from client:")
+			print (output)
+
+	except:
+		sys.exit(0)

subject.en.txt

@@ -0,0 +1,42 @@
+Assignment name  : mini_serv
+Expected files   : mini_serv.c
+Allowed functions: write, close, select, socket, accept, listen, send, recv, bind, strstr, malloc, realloc, free, calloc, bzero, atoi, sprintf, strlen, exit, strcpy, strcat, memset
+--------------------------------------------------------------------------------
+
+Write a program that will listen for client to connect on a certain port on 127.0.0.1 and will let clients to speak with each other
+
+This program will take as first argument the port to bind to
+If no argument is given, it should write in stderr "Wrong number of arguments" followed by a \n and exit with status 1
+If a System Calls returns an error before the program start accepting connection, it should write in stderr "Fatal error" followed by a \n and exit with status 1
+If you cant allocate memory it should write in stderr "Fatal error" followed by a \n and exit with status 1
+
+Your program must be non-blocking but client can be lazy and if they don't read your message you must NOT disconnect them...
+
+Your program must not contains #define preproc
+Your program must only listen to 127.0.0.1
+The fd that you will receive will already be set to make 'recv' or 'send' to block if select hasn't be called before calling them, but will not block otherwise. 
+
+When a client connect to the server:
+- the client will be given an id. the first client will receive the id 0 and each new client will received the last client id + 1
+- %d will be replace by this number
+- a message is sent to all the client that was connected to the server: "server: client %d just arrived\n"
+
+clients must be able to send messages to your program.
+- message will only be printable characters, no need to check
+- a single message can contains multiple \n
+- when the server receive a message, it must resend it to all the other client with "client %d: " before every line!
+
+When a client disconnect from the server:
+- a message is sent to all the client that was connected to the server: "server: client %d just left\n"
+
+Memory or fd leaks are forbidden
+
+To help you, you will find the file main.c with the beginning of a server and maybe some useful functions. (Beware this file use forbidden functions or write things that must not be there in your final program)
+
+Warning our tester is expecting that you send the messages as fast as you can. Don't do un-necessary buffer.
+
+Evaluation can be a bit longer than usual...
+
+Hint: you can use nc to test your program
+Hint: you should use nc to test your program
+Hint: To test you can use fcntl(fd, F_SETFL, O_NONBLOCK) but use select and NEVER check EAGAIN (man 2 send)