#include<stdio.h>
#include<stdlib.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<arpa/inet.h>
#include<unistd.h>
#include<arpa/inet.h>
#include<netdb.h>
#include<fcntl.h>

#define WPORT 8008

/* really simple web server that binds to port WPORT 
   It simply reads from a local file and pumps it over the socket
*/

void service(int cfd)   // called by main server loop
{ int ffd;        // local file descriptor
  int n;  // bytes read
  char buf[1024];
  char buf1[512];
  char buf2[128];
  char page[128];  // filename of page

  // parse request
  n = read(cfd,buf1,511);
  buf1[n]=0;  // 0-terminate string  (just to be sure!)
  sscanf(buf1,"GET /home/%s %s\n",page,buf2);

  printf("page is %s\n",page);

  // open local file
  ffd = open(page,O_RDONLY,0);
  if (ffd<0) ffd = open("index.html",O_RDONLY,0); // default

  // send OK
  sprintf(buf,"HTTP/1.1 200 OK\n");
  write(cfd,buf,strlen(buf)+1);

  n = 1024;
  while(n>0)
      {
	  n = read(ffd,buf,1024);
	  if (n>0) write(cfd,buf,n);
      }
  
  close(ffd);
  close(cfd);
} // service

int main(int argc, char** argv)
{
    int sfd, cfd;   // server and communication sockets
    int n, len;    
    struct sockaddr_in saddr;  // used locally by bind
    struct sockaddr_in caddr;  // info about a client
    
    saddr.sin_family = AF_INET;
    saddr.sin_addr.s_addr = htonl(INADDR_ANY); // allow any interface
    saddr.sin_port = htons(WPORT);
    len = sizeof(saddr);
    
    // steps to create the server (listening) socket
    sfd = socket(AF_INET,SOCK_STREAM,0);

    n = 1;
    setsockopt(sfd,SOL_SOCKET,SO_REUSEADDR,&n,sizeof(int));

    bind(sfd,(struct sockaddr*)&saddr,len);
    listen(sfd,16);  // sets # of clients that can be queued

    len = sizeof(caddr);
    
    for(;;)
    {
     // wait for client connection, 
     // create communication socket (cfd),
     // and record client info in caddr
     cfd = accept(sfd,(struct sockaddr*)&caddr,&len);
     if (cfd<1) exit(1);
     printf("connection from %s\n", inet_ntoa(caddr.sin_addr));
     
     service(cfd);
    
     close(cfd);
    }  // server loop
    
    exit(0);
}