lcdproc/server/sock.c

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

#include "../shared/sockets.h"
#include "sock.h"
#include "clients.h"
#include "../shared/debug.h"


/**************************************************
  LCDproc sockets code...

  This is messy, and needs to be finished.
**************************************************/

fd_set active_fd_set, read_fd_set;
int orig_sock;

// Length of longest transmission allowed at once...
#define MAXMSG 8192


int read_from_client (int filedes);


// Creates a socket in internet space
int
sock_create_inet_socket (unsigned short int port)
{
   struct sockaddr_in name;
   int sock;

   debug ("sock_create_inet_socket(%i)\n", port);

   /* Create the socket. */
   //debug("Creating Inet Socket\n");
   sock = socket (PF_INET, SOCK_STREAM, 0);
   if (sock < 0) {
      perror ("Error creating socket");
      return -1;
   }

   /* Give the socket a name. */
   //debug("Binding Inet Socket\n");
   name.sin_family = AF_INET;
   name.sin_port = htons (port);
   name.sin_addr.s_addr = htonl (INADDR_ANY);
   if (bind (sock, (struct sockaddr *) &name, sizeof (name)) < 0) {
      perror ("Error binding socket");
      return -1;
   }

   return sock;

}

//int StartSocketServer()
int
sock_create_server ()
{
   int sock;

   debug ("sock_create_server()\n");

   /* Create the socket and set it up to accept connections. */
   sock = sock_create_inet_socket (LCDPORT);
   if (sock < 0) {
      perror ("sock_create_server: Error creating socket");
      return -1;
   }


   if (listen (sock, 1) < 0) {
      perror ("sock_create_server: Listen error");
      return -1;
   }

   /* Initialize the set of active sockets. */
   FD_ZERO (&active_fd_set);
   FD_SET (sock, &active_fd_set);

   orig_sock = sock;

/*
  {
     int val, len, sock;
     sock = new;
     
     len = sizeof(int);
     getsockopt(sock, SOL_SOCKET, SO_SNDBUF, &val, &len);
     printf("SEND buffer: %i bytes\n", val);

     len = sizeof(int);
     getsockopt(sock, SOL_SOCKET, SO_RCVBUF, &val, &len);
     printf("RECV buffer: %i bytes\n", val);
  }
*/

   return sock;
}


int
sock_poll_clients ()
{
   int i;
   int err;
   struct sockaddr_in clientname;
   size_t size;
   struct timeval t;
   client *c;

   //debug("sock_poll_clients()\n");

   t.tv_sec = 0;
   t.tv_usec = 0;

   /* Block until input arrives on one or more active sockets. */
   read_fd_set = active_fd_set;

   if (select (FD_SETSIZE, &read_fd_set, NULL, NULL, &t) < 0) {
      perror ("sock_poll_clients: Select error");
      return -1;
   }

   /* Service all the sockets with input pending. */
   for (i = 0; i < FD_SETSIZE; ++i) {
      if (FD_ISSET (i, &read_fd_set)) {
	 if (i == orig_sock) {
	    /* Connection request on original socket. */
	    int new;
	    size = sizeof (clientname);
	    new = accept (orig_sock, (struct sockaddr *) &clientname, &size);
	    if (new < 0) {
	       perror ("sock_poll_clients: Accept error");
	       return -1;
	    }
	    debug ("sock_poll_clients: connect from host %s, port %hd.\n", inet_ntoa (clientname.sin_addr), ntohs (clientname.sin_port));
	    FD_SET (new, &active_fd_set);

	    fcntl (new, F_SETFL, O_NONBLOCK);


	    // TODO:  Create new "client" here...  (done?)
	    if (client_create (new) == NULL) {
	       fprintf (stderr, "sock_poll_clients: error creating client %i\n", i);
	       return -1;
	    }
	 } else {
	    /* Data arriving on an already-connected socket. */
	    err = 0;
	    do {
	       debug ("sock_poll_clients: reading...\n");
	       err = read_from_client (i);
	       debug ("sock_poll_clients: ...done\n");
	       if (err < 0) {
		  // TODO:  Destroy a "client" here... (done?)
		  c = client_find_sock (i);
		  if (c) {
		     //sock_send_string(i, "bye\n");
		     client_destroy (c);
		     close (i);
		     FD_CLR (i, &active_fd_set);
		     debug ("sock_poll_clients: Closed connection %i\n", i);
		  } else
		     fprintf (stderr, "sock_poll_clients: Can't find client %i\n", i);
	       }
	    } while (err > 0);

	 }
      }
   }
   return 0;
}


int
read_from_client (int filedes)
{
   char buffer[MAXMSG];
   int nbytes, i;
   client *c;

//   nbytes = read (filedes, buffer, MAXMSG);
   //debug("read_from_client(%i): reading...\n", filedes);
   nbytes = sock_recv (filedes, buffer, MAXMSG);
   //debug("read_from_client(%i): ...done\n", filedes);
   debug ("read_from_client(%i): %i bytes\n", filedes, nbytes);


   if (nbytes < 0)		// Read error?  No data available?
   {
      // TODO:  check errno here!
      //fprintf (stderr,"read_from_client: Read error\n");
      return 0;
   } else if (nbytes == 0)	// EOF
      return -1;
   else if (nbytes > (MAXMSG - (MAXMSG / 8)))	// Very noisy client...
   {
      sock_send_string (filedes, "huh? Shut up!\n");
      return -1;
   } else			// Data Read
   {
      buffer[nbytes] = 0;
      // Now, replace zeros with linefeeds...
      for (i = 0; i < nbytes; i++)
	 if (buffer[i] == 0)
	    buffer[i] = '\n';
      // Enqueue a "client message" here...
      c = client_find_sock (filedes);
      if (c) {
	 client_add_message (c, buffer);
      } else
	 fprintf (stderr, "read_from_client:  Can't find client %i\n", filedes);

      debug ("read_from_client: got message: `%s'\n", buffer);
      return nbytes;
   }
   return nbytes;
}

// FIXME: This talks to all open files, including
// stdin, stdout, stderr, the LCD, etc...
// BUT it should only talk to sockets!
int
sock_close_all ()
{
   int i;

   debug ("sock_close_all()\n");

   for (i = 0; i < FD_SETSIZE; i++) {
      // TODO:  Destroy a "client" here...?  Nope.
      sock_send_string (i, "bye\n");
      close (i);
      FD_CLR (i, &active_fd_set);
      debug ("sock_close_all: Closed connection %i\n", i);
   }

   return 0;

}