int main(int argc, char *argv[]) {
int s_listen, s_accepted;
int port;
struct sockaddr_in saddr, caddr;
FILE *fsock_in, *fsock_out;
uint caddr_len;
char request_str[MAX_REQUEST_LEN];
char type[MAX_COMMAND_LEN];
char filename[MAX_FILENAME_LEN];
char buffer[DATA_CHUNK_SIZE];
char *buffer2; // for xdr
int receive_requests;
FILE *file;
uint32_t file_size, last_modification, file_size_n, last_modification_n;
struct stat sb;
uint n_read;
call_msg request;
response_msg response;
XDR xdrs_in, xdrs_out;
int pid;
if(argc < 2) {
fprintf(stderr, "Usage: %s <port>\n", argv[0]);
return 1;
}
port = atoi(argv[1]);
if(port == 0) {
fprintf(stderr, "Invalid port\n");
return 1;
}
saddr.sin_port = htons(port);
saddr.sin_family = AF_INET;
saddr.sin_addr.s_addr = INADDR_ANY;
s_listen = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if(s_listen < 0) {
perror("Impossible to create socket");
return 1;
}
printf("Created listen socket\n");
if(bind(s_listen, (struct sockaddr *)&saddr, sizeof(saddr)) < 0) {
perror("Impossible to bind");
return 1;
}
printf("Socket bound to address\n");
if(listen(s_listen, BACKLOG) < 0) {
perror("Impossible to listen");
return 1;
}
printf("Socket listen done\n");
signal(SIGPIPE, sigpipeHndlr);
//signal(SIGINT, killMyChildren);
for(int i = 0; i < 3; i++) {
pid = fork();
if(pids[i] < 0) {
printf("Impossible to create another process\n");
break;
}
if(pid) {
// parent
pids[i] = pid;
} else {
// child
break;
}
}
if(pid) {
killMyChildren(0);
return 0;
}
while(1) {
caddr_len = sizeof(caddr);
printf("Waiting for a client to connect\n");
s_accepted = accept(s_listen, (struct sockaddr *)&caddr, &caddr_len);
sigpipe = 0;
if(s_accepted < 0) {
perror("Impossible to accept");
break;
}
printf("Accepted a connection from %s:%d\n", inet_ntoa(caddr.sin_addr), ntohs(caddr.sin_port));
fsock_in = fdopen(s_accepted, "r");
if(fsock_in == NULL) {
perror("Impossible to do fdopen r");
close(s_accepted);
continue;
}
fsock_out = fdopen(s_accepted, "w");
if(fsock_out == NULL) {
perror("Impossible to do fdopen w");
fclose(fsock_in);
close(s_accepted);
continue;
}
xdrstdio_create(&xdrs_in, fsock_in, XDR_DECODE);
xdrstdio_create(&xdrs_out, fsock_out, XDR_ENCODE);
setbuf(fsock_out, 0);
setbuf(fsock_in, 0);
receive_requests = 1;
while(receive_requests) {
memset(request_str, 0, MAX_REQUEST_LEN);
memset(&request, 0, sizeof(call_msg));
memset(&response, 0, sizeof(response_msg));
if(!xdr_call_msg(&xdrs_in, &request)) {
printf("Error receiving request. Client closed connection\n");
break;
}
if(request.ctype == QUIT) {
printf("Client asked to quit\n");
break;
} else if(request.ctype != GET) {
printf("Unknown request received\n");
break;
}
strncpy(filename, request.call_msg_u.filename, FILENAME_MAX);
printf("Received a GET request for file: %s\n", filename);
if(stat(filename, &sb)) {
perror("Impossible to stat requested file");
response = ERR;
xdr_response_msg(&xdrs_out, &response);
continue;
}
if((sb.st_mode & S_IFMT) != S_IFREG) {
perror("The requested file is no a regular file");
response = ERR;
xdr_response_msg(&xdrs_out, &response);
continue;
}
file_size = sb.st_size;
last_modification = sb.st_mtim.tv_sec;
file_size_n = htonl(file_size);
last_modification_n = htonl(last_modification);
file = fopen(filename, "r");
if(file == NULL) {
perror("Impossible to open requested file");
fprintf(fsock_out, ERR_MSG);
continue;
}
printf("Sending message\n");
response = OK;
xdr_response_msg(&xdrs_out, &response);
printf("Sending size and modification time\n");
fwrite(&file_size_n, sizeof(uint32_t), 1, fsock_out);
//fwrite(&last_modification_n, sizeof(uint32_t), 1, fsock_out);
printf("Sending the file\n");
while((n_read = fread(buffer, sizeof(char), DATA_CHUNK_SIZE, file)) > 0) {
fwrite(buffer, sizeof(char), n_read, fsock_out);
if(sigpipe) {
printf("Client closed socket\n");
receive_requests = 0;
fclose(file);
break;
}
}
if(!receive_requests) {
break;
}
fclose(file);
printf("File sent\n");
}
xdr_destroy(&xdrs_in);
xdr_destroy(&xdrs_out);
fclose(fsock_out);
fclose(fsock_in);
close(s_accepted);
}
return 0;
}
int main(int argc, char** argv) {
char rbuf[MAXBUF]; // transmitter and receiver buffers
SOCKET s; // socket
struct in_addr sIPaddr; // server IP address structure
struct sockaddr_in saddr; // server address structure
uint16_t tport_n, tport_h; // server port number by htons()
char *filename;
FILE* fp;
uint32_t fileBytesN, fileBytes, nNext, nLeft;
ssize_t nread, nwritten;
XDR xdrs_in; // Input XDR stream
XDR xdrs_out; // Output XDR stream
FILE* stream_socket_r; // FILE stream for reading from the socket
FILE* stream_socket_w; // FILE stream for writing to the socket
call_msg reqMessage;
response_msg resMessage;
/* Check number of arguments */
checkArg(argc, 4);
prog_name = argv[0];
/* Set IP address */
setIParg(argv[1], &sIPaddr);
/* Set port number */
tport_n = setPortarg(argv[2], &tport_h);
/* Save the file to request */
filename = argv[3];
/* Create the socket */
fprintf(stdout, "Creating the socket...\n");
s = Socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
fprintf(stdout, "- OK. Socket fd: %d\n", s);
/* Prepare server address structure */
saddr.sin_family = AF_INET;
saddr.sin_port = tport_n;
saddr.sin_addr = sIPaddr;
/* Send connection request */
fprintf(stdout, "Connecting to target address...\n");
Connect(s, (struct sockaddr*) &saddr, sizeof(saddr));
fprintf(stdout, "- OK. Connected to ");
showAddress(&saddr);
/* Open FILE reading stream and bind it to the corresponding XDR stream */
stream_socket_r = fdopen(s, "r");
if (stream_socket_r == NULL) {
fprintf(stderr, "---ERROR. fdopen() failed.\n");
return 1;
}
xdrstdio_create(&xdrs_in, stream_socket_r, XDR_DECODE);
/* Open FILE writing stream and bind it to the corresponding XDR stream */
stream_socket_w = fdopen(s, "w");
if (stream_socket_w == NULL) {
fprintf(stderr, "---ERROR. fdopen() failed.\n");
xdr_destroy(&xdrs_in);
fclose(stream_socket_r);
return 1;
}
xdrstdio_create(&xdrs_out, stream_socket_w, XDR_ENCODE);
while(1) {
/* Send a file request */
reqMessage.ctype = GET;
reqMessage.call_msg_u.filename = filename;
if (!xdr_call_msg(&xdrs_out, &reqMessage)) {
fprintf(stdout, "- ERROR sending GET message.\n");
break;
}
fflush(stream_socket_w);
/* Receive a message */
if (!xdr_response_msg(&xdrs_in, &resMessage)) {
fprintf(stdout, "- ERROR. Response xdr_response_msg() failed.\n");
break;
}
fprintf(stdout, "- Received response.\n");
if (resMessage == OK) {
fprintf(stdout, "- File received: %s\n", filename);
// Read the file size
nread = read(s, (void*)&fileBytesN, sizeof(uint32_t));
fileBytes = ntohl(fileBytesN);
fprintf(stdout, "- File size: %u\n", fileBytesN);
// Received and write file
fp = Fopen(filename, "wb");
nLeft = fileBytes;
while(nLeft > 0) {
if (nLeft < MAXBUF) {
nNext = nLeft;
} else {
nNext = MAXBUF;
}
nread = Read(s, rbuf, nNext*sizeof(char));
nwritten = Fwrite(rbuf, sizeof(char), nNext, fp);
if (nread != nNext || nwritten != nNext) {
fprintf(stdout, "--- ERROR saving file.\n");
break;
}
nLeft -= nNext;
}
Fclose(fp);
fprintf(stdout, "--- File written: %s\n", filename);
} else if (resMessage == ERR) {
fprintf(stderr, "- Received ERR message.\n");
break;
} else {
fprintf(stderr, "- ERROR. Something goes wrong with the communication protocol.\n");
break;
}
/* End the communication */
reqMessage.ctype = QUIT;
reqMessage.call_msg_u.filename = NULL;
if (!xdr_call_msg(&xdrs_out, &reqMessage)) {
fprintf(stdout, "- ERROR sending QUIT message.\n");
break;
}
fprintf(stdout, "- QUIT message sent.\n");
fflush(stream_socket_r);
fflush(stream_socket_w);
break;
}
xdr_destroy(&xdrs_in);
fclose(stream_socket_r);
xdr_destroy(&xdrs_out);
fclose(stream_socket_w);
/* Close the socket connection */
fprintf(stdout, "Closing the socket connection...\n");
closesocket(s);
fprintf(stdout, "- OK. Closed.\n");
return 0;
}