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static char rcsid[] = "$Id: tcpserv.c,v 1.1 2001/12/02 12:13:52 as Exp as $";
/************************************************************************
*
* Example of server using TCP protocol.
*
***********************************************************************/
#include <unistd.h>
#include <sys/stat.h> // open()
#include "inet.h"
#include "error.cpp"
#include "util.cpp"
#include <iostream>
#include <time.h>
#include <fstream>
using namespace std;
// Constant definitions
//
// maximum line length
const int MAXLINE=255;
// structure for phone book records
struct telEintrag { // Einzelne Eintr�ge im Telefonbuch
char name[50];
char tel[50];
};
// max. 50 records in a phone book
// global variables
//
// TODO: change to file or shared memory
// global variables are not good with fork()
//
telEintrag telBuch[50]; // 50 Eintr�ge m�glich
int telCount = 0; // Position des n�chsten freien Platzes
// write a line to socket sockfd
void myWrite(int sockfd, char *line) {
int n;
// send reply
n = strlen(line);
if (writen(sockfd, line, n) != n) {
err_dump("str_echo: writen error");
}
}
// read line from socket sockfd
void myRead(int sockfd, char *line) {
int n;
// receive data into line
n = readline(sockfd, line, MAXLINE);
// error handling
if (n == 0) {
return; /* connection terminated */
}
else if (n < 0) {
err_dump("str_echo: readline error");
}
// console logging
// time_t structure variable myTime
time_t myTime;
// read time into myTime
time(&myTime);
// char array for time conversion
char tmpTime[25];
// copy converted time into char array
strcpy(tmpTime, ctime(&myTime));
// append string terminating binary 0
tmpTime[strlen(tmpTime)-1] = '\0';
// print time and received line to stdout
printf("[%s] Nachricht: %s",tmpTime,line);
}
void str_echo(int sockfd)
{
int n;
char line[MAXLINE];
for ( ; ; ) {
// read line from socket
myRead(sockfd, line);
// if "addEntry"-command was sent
if (strcmp(line, "addEntry\n") == 0) {
// send back "OK", we understood the command
myWrite(sockfd, "OK\n");
// now we receive the name
myRead(sockfd, line);
// name received
myWrite(sockfd, "OK\n");
// save it in local memory
strcpy(telBuch[telCount].name, line);
// now we receive the phone number
myRead(sockfd, line);
// number received
myWrite(sockfd, "OK\n");
// save the number in local memory
strcpy(telBuch[telCount].tel, line);
// next time we fill the next array element
telCount++;
// we did it
printf("Neuer Eintrag im Telefonbuch.\n");
} else
// the "searchEntry"-command was sent
if (strcmp(line, "searchEntry\n") == 0) {
// send back "OK", we understood the command
myWrite(sockfd, "OK\n");
// receive the search string
myRead(sockfd, line);
// search the entry
int i=0;
bool found = false;
for (i; i < telCount; i++) {
if (strcmp(telBuch[i].name, line) == 0) {
found = true;
// we found an entry
// send back the phone number
myWrite(sockfd, telBuch[i].tel);
}
}
// we did not find anything
if (found == false)
myWrite(sockfd, "Nicht gefunden.\n");
} else if (strcmp(line,"end\n")==0)
{
// client sent end command
// exiting...
myWrite(sockfd,"Server exiting... \n");
exit(0);
}
else
{
// an undefined command was sent from client
myWrite(sockfd, "Command not found.\n");
}
}
}
/***********************************************************************/
/************************************************************************
* main function, server for the TCP/IP echo server
*/
int main(int argc, char **argv)
{
int sockfd, newsockfd, clilen, childpid;
// structures of socket addresses
struct sockaddr_in cli_addr, serv_addr;
pname = argv[0];
// Open a TCP socket (an Internet stream socket).
if ( (sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
err_dump("server: can't open stream socket");
// Bind our local address so that the client can send to us.
// make sure zeros are in serv_addr
bzero((char *) &serv_addr, sizeof(serv_addr));
// now fill in information, which we need
serv_addr.sin_family = AF_INET;
// INADDR_ANY: System definiton -> accept connections on every interface
// htonl: convert byte order (host to network long)
serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
// SERV_TCP_PORT defined in inet.h
// htons: convert byte order (host to network short)
serv_addr.sin_port = htons(SERV_TCP_PORT);
// bind sockfd to socket address serv_addr (Server)
if (bind(sockfd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0)
err_dump("server: can't bind local address");
// mark socket to accept connections
// limit 5 connections backlog in queue
listen(sockfd, 5);
for ( ; ; ) {
// Wait for a connection from a client process.
// This is an example of a concurrent server.
clilen = sizeof(cli_addr);
// make new socket for client connection and return
// the file descriptor of this socket
newsockfd = accept(sockfd, (struct sockaddr *) &cli_addr,
(socklen_t *) &clilen);
if (newsockfd < 0)
err_dump("server: accept error");
if ( (childpid = fork()) < 0)
err_dump("server: fork error");
else if (childpid == 0) { // child process
printf("Verbinung aufgebaut.\n");
close(sockfd); // close original socket
str_echo(newsockfd); // process the request
exit(0);
}
close(newsockfd); // parent process
}
}
/***********************************************************************/
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