Multithread-Dateiübertragung mit Socket
Ich versuche, ein Server-Client-Dateiübertragungssystem mit mehreren Threads in C zu erstellen. Es gibt Clients, die senden oder auflisten oder eine andere Auswahl treffen (in einem Switch-Fall, den Sie sehen können), und einen Server, der die Dateien speichert und a Viele Kunden.
Multi-Thread-Ideologie ist wirklich schwierig, soweit ich sehen kann. Es braucht zu viel Erfahrung statt Wissen. Ich arbeite seit mehr als einer Woche an dem Projekt und konnte die Probleme nicht in den Griff bekommen.
Es gibt 4 Auswahlmöglichkeiten: Die erste Option listet lokale Dateien des Clients in seinem Verzeichnis auf, die zweite Option listet Dateien auf, die zwischen dem Client und dem Server übertragen werden, und die dritte Option liest den Dateinamen des Benutzers und kopiert die Datei in das Serververzeichnis.
Mein zentrales Thema hier ist das Multithreading. Ich kann nicht mehrere Clients verbinden. Ich habe den Code unzählige Male gelesen, aber ich kann meine Fehler wirklich nicht fassen und stecke fest.
Das andere Problem ist, dass der Client endet, wenn dasSIGINT wird abgefangen, aber wenn Sie beispielsweise bei gedrückter Strg-C-Taste Listendateien auswählen, wird dies nicht beendet. Gleiches Problem auch für die Server-Datei. Es ist lästiger im Vergleich zum Fangen des Clients, denn wenn der Server @ bekomSIGINT, Clients werden jeweils vom Server getrennt.
Vielen Dank für Ihre Hilfe!
server.c
/*
Soner
Receive a file over a socket.
Saves it to output.tmp by default.
Interface:
./executable [<port>]
Defaults:
- output_file: output.tmp
- port: 12345
*/
#define _XOPEN_SOURCE 700
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <arpa/inet.h>
#include <fcntl.h>
#include <netdb.h> /* getprotobyname */
#include <netinet/in.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <unistd.h>
#include <pthread.h>
pthread_mutex_t mutex1 = PTHREAD_MUTEX_INITIALIZER;
enum { PORTSIZE = 5 };
void* forClient(void* ptr);
void sig_handler(int signo)
{
if (signo == SIGINT)
printf("!! OUCH, CTRL - C received by server !!\n");
}
int main(int argc, char **argv) {
struct addrinfo hints, *res;
int enable = 1;
int filefd;
int server_sockfd;
unsigned short server_port = 12345u;
char portNum[PORTSIZE];
socklen_t client_len[BUFSIZ];
struct sockaddr_in client_address[BUFSIZ];
int client_sockfd[BUFSIZ];
int socket_index = 0;
pthread_t threads[BUFSIZ];
if (argc != 2) {
fprintf(stderr, "Usage ./server <port>\n");
exit(EXIT_FAILURE);
}
server_port = strtol(argv[1], NULL, 10);
memset(&hints, 0, sizeof hints);
hints.ai_family = AF_INET; //ipv4
hints.ai_socktype = SOCK_STREAM; // tcp
hints.ai_flags = AI_PASSIVE; // fill in my IP for me
sprintf(portNum, "%d", server_port);
getaddrinfo(NULL, portNum, &hints, &res);
server_sockfd = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
if (server_sockfd == -1) {
perror("socket");
exit(EXIT_FAILURE);
}
if (setsockopt(server_sockfd, SOL_SOCKET, (SO_REUSEPORT | SO_REUSEADDR), &enable, sizeof(enable)) < 0) {
perror("setsockopt(SO_REUSEADDR) failed");
exit(EXIT_FAILURE);
}
if (bind(server_sockfd, res->ai_addr, res->ai_addrlen) == -1) {
perror("bind");
exit(EXIT_FAILURE);
}
if (listen(server_sockfd, 5) == -1) {
perror("listen");
exit(EXIT_FAILURE);
}
fprintf(stderr, "listening on port %d\n", server_port);
while (1) {
, client_len[socket_index] = sizeof(client_address[socket_index]);
puts("waiting for client");
client_sockfd[socket_index] = accept(
server_sockfd,
(struct sockaddr*)&client_address[socket_index],
&client_len[socket_index]
);
if (client_sockfd[socket_index] < 0) {
perror("Cannot accept connection\n");
close(server_sockfd);
exit(EXIT_FAILURE);
}
pthread_create( &threads[socket_index], NULL, forClient, (void*)client_sockfd[socket_index]);
if(BUFSIZ == socket_index) {
socket_index = 0;
} else {
++socket_index;
}
pthread_join(threads[socket_index], NULL);
close(filefd);
close(client_sockfd[socket_index]);
}
return EXIT_SUCCESS;
}
void* forClient(void* ptr) {
int connect_socket = (int) ptr;
int filefd;
ssize_t read_return;
char buffer[BUFSIZ];
char *file_path;
char receiveFileName[BUFSIZ];
int ret = 1;
// Thread number means client's id
printf("Thread number %ld\n", pthread_self());
pthread_mutex_lock( &mutex1 );
// until stop receiving go on taking information
while (recv(connect_socket, receiveFileName, sizeof(receiveFileName), 0)) {
file_path = receiveFileName;
fprintf(stderr, "is the file name received? ? => %s\n", file_path);
filefd = open(file_path,
O_WRONLY | O_CREAT | O_TRUNC,
S_IRUSR | S_IWUSR);
if (filefd == -1) {
perror("open");
exit(EXIT_FAILURE);
}
do {
read_return = read(connect_socket, buffer, BUFSIZ);
if (read_return == -1) {
perror("read");
exit(EXIT_FAILURE);
}
if (write(filefd, buffer, read_return) == -1) {
perror("write");
exit(EXIT_FAILURE);
}
} while (read_return > 0);
}
pthread_mutex_unlock( &mutex1 );
fprintf(stderr, "Client dropped connection\n");
pthread_exit(&ret);
}
client.c
/*
Soner
Send a file over a socket.
Interface:
./executable [<sever_hostname> [<port>]]
Defaults:
- server_hostname: 127.0.0.1
- port: 12345
*/
#define _XOPEN_SOURCE 700
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <arpa/inet.h>
#include <fcntl.h>
#include <netdb.h> /* getprotobyname */
#include <netinet/in.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <unistd.h>
// NOTE/BUG: this didn't provide enough space for a 5 digit port + EOS char
#if 0
enum { PORTSIZE = 5 };
#else
enum { PORTSIZE = 6 };
#endif
void
sig_handler(int signo)
{
if (signo == SIGINT)
printf("!! OUCH, CTRL - C received on client !!\n");
}
int
main(int argc, char **argv)
{
struct addrinfo hints,
*res;
char *server_hostname = "127.0.0.1";
char file_path[BUFSIZ];
char *server_reply = NULL;
char *user_input = NULL;
char buffer[BUFSIZ];
int filefd;
int sockfd;
ssize_t read_return;
struct hostent *hostent;
unsigned short server_port = 12345;
char portNum[PORTSIZE];
char remote_file[BUFSIZ];
int select;
char *client_server_files[BUFSIZ];
int i = 0;
int j;
// char filename_to_send[BUFSIZ];
if (argc != 3) {
fprintf(stderr, "Usage ./client <ip> <port>\n");
exit(EXIT_FAILURE);
}
server_hostname = argv[1];
server_port = strtol(argv[2], NULL, 10);
/* Prepare hint (socket address input). */
hostent = gethostbyname(server_hostname);
if (hostent == NULL) {
fprintf(stderr, "error: gethostbyname(\"%s\")\n", server_hostname);
exit(EXIT_FAILURE);
}
memset(&hints, 0, sizeof hints);
hints.ai_family = AF_INET; // ipv4
hints.ai_socktype = SOCK_STREAM; // tcp
hints.ai_flags = AI_PASSIVE; // fill in my IP for me
sprintf(portNum, "%d", server_port);
getaddrinfo(NULL, portNum, &hints, &res);
sockfd = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
if (sockfd == -1) {
perror("socket");
exit(EXIT_FAILURE);
}
/* Do the actual connection. */
if (connect(sockfd, res->ai_addr, res->ai_addrlen) == -1) {
perror("connect");
return EXIT_FAILURE;
}
while (1) {
if (signal(SIGINT, sig_handler)) {
break;
}
puts("connected to the server");
puts("-----------------");
puts("|1 - listLocal| \n|2 - listServer| \n|3 - sendFile| \n|4 - help| \n|5 - exit| ");
puts("-----------------");
while (1) {
scanf("%d", &select);
switch (select) {
case 1: // list files of client's directory
system("find . -maxdepth 1 -type f | sort");
break;
case 2: // listServer
puts("---- Files btw Server and the Client ----");
for (j = 0; j < i; ++j) {
puts(client_server_files[j]);
}
break;
case 3: // send file
memset(file_path, 0, sizeof file_path);
scanf("%s", file_path);
memset(remote_file, 0, sizeof remote_file);
// send file name to server
sprintf(remote_file, "%s", file_path);
send(sockfd, remote_file, sizeof(remote_file), 0);
filefd = open(file_path, O_RDONLY);
if (filefd == -1) {
perror("open send file");
//exit(EXIT_FAILURE);
break;
}
while (1) {
read_return = read(filefd, buffer, BUFSIZ);
if (read_return == 0)
break;
if (read_return == -1) {
perror("read");
//exit(EXIT_FAILURE);
break;
}
if (write(sockfd, buffer, read_return) == -1) {
perror("write");
//exit(EXIT_FAILURE);
break;
}
}
// add files in char pointer array
client_server_files[i++] = file_path;
close(filefd);
break;
case 5:
free(user_input);
free(server_reply);
exit(EXIT_SUCCESS);
default:
puts("Wrong selection!");
break;
}
}
}
free(user_input);
free(server_reply);
exit(EXIT_SUCCESS);
}