/* server.c
 * Copyright Mark Watson 1999. Open Source Software License.
 */

#include <stdio.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>      

int port = 8000;

void main() {
  struct sockaddr_in sin;
  struct sockaddr_in pin;
  int sock_descriptor;
  int temp_sock_descriptor;
  int address_size;
  char buf[16384];
  int i, len;

  sock_descriptor = socket(AF_INET, SOCK_STREAM, 0);
  if (sock_descriptor == -1) {
    perror("call to socket");
    exit(1);
  }

  bzero(&sin, sizeof(sin));
  sin.sin_family = AF_INET;
  sin.sin_addr.s_addr = INADDR_ANY;
  sin.sin_port = htons(port);

  if (bind(sock_descriptor, (struct sockaddr *)&sin, sizeof(sin)) == -1) {
    perror("call to bind");
    exit(1);
  }

  if (listen(sock_descriptor, 20) == -1) {
    perror("call to listen");
    exit(1);
  }

  printf("Accepting connections ...\n"); 

  while(1) {
    temp_sock_descriptor =
      accept(sock_descriptor, (struct sockaddr *)&pin,
	     &address_size);
    if (temp_sock_descriptor == -1) {
      perror("call to accept");
      exit(1);
    }

    if (recv(temp_sock_descriptor, buf, 16384, 0) == -1) {
      perror("call to recv");
      exit(1);
    }

    printf("received from client:%s\n", buf);

    // for this server example, we just convert the
    // characters to upper case:

    len = strlen(buf);
    for (i=0; i<len; i++) buf[i] = toupper(buf[i]);
    
    if (send(temp_sock_descriptor, buf, len, 0) == -1) {
      perror("call to send");
      exit(1);
    }

    close(temp_sock_descriptor);

  }
}