source: npl/mediabox/lcdproc_edwin/src/server/clients.c

/*

  clients.c

  Inits/shuts down client system,
  creates/destroys individual clients,
  enqueues/dequeues messages from clients,
  and searches for clients in the list.

  :)

 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>

#include "clients.h"
#include "client_data.h"
#include "../shared/debug.h"



LL * clients;

// Initialize and kill client list...
int client_init()
{
   debug("client_init()\n");
   
   clients = LL_new();
   if(!clients)
   {
      fprintf(stderr, "client_init:  Unable to create client list\n");
      return -1;
   }

   return 0;
}

int client_shutdown()
{
   // TODO:  Close all connections first...
   client *c;

   debug("client_shutdown()\n");
   
   
   // Free all client structures...
   // Note that the regular list loop doesn't work here, because
   // client_destroy() calls LL_Remove()
   for(c = LL_Pop(clients);
       c;
       c = LL_Pop(clients))
   {
      debug("client_shutdown: ...\n");
      if(c)
      {
         debug("client_shutdown: ... %i ...\n", c->sock);
         if(0 != client_destroy(c))
         {
            fprintf(stderr, "client_shutdown: Error freeing client\n");
         }
         else
         {
            debug("client_shutdown: Freed client...\n");
         }
      }
      else
      {
         debug("client_shutdown: No client!\n");
      }
   }

   // Then, free the list...
   LL_Destroy(clients);
   
   debug("client_shutdown: done\n");

   return 0;
}


// Create and destroy clients....
client * client_create(int sock)
{
   client *c;

   debug("client_create(%i)\n", sock);

   // Allocate new client...
   c = malloc(sizeof(client));
   if(!c)
   {
      fprintf(stderr, "client_create: error allocating new client\n");
      return NULL;
   }

   // Init struct members
   c->sock = 0;
   c->data = NULL;
   c->messages = NULL;


   c->sock = sock;

   // Set up message list...
   c->messages = LL_new();
   if(!c->messages)
   {
      fprintf(stderr, "client_create: error allocating message list\n");
      free(c);
      return NULL;
   }

   // TODO:  allocate and init client data...
   c->data = malloc(sizeof(client_data));
   if(!c->data)
   {
      fprintf(stderr, "client_create: error allocating client data\n");
      free(c->messages);
      free(c);
      return NULL;
   }
   else if(client_data_init(c->data) < 0)
   {
      return NULL;
   }
   
   // TODO:  Check for errors while adding the client to the list?
   LL_Push(clients, (void *)c);
   
   return c;
}
int client_destroy(client *c)
{
   // TODO:  Close the socket connection here?
   int err;
   
   char *str;

   debug("client_destroy()\n");
   
   if(!c) return -1;

   // Eat the rest of the incoming requests...
   debug("client_destroy: get_messages\n");
   while((str = client_get_message(c)))
   {
      if(str) {
         debug("client_destroy: kill message %s\n", str);
         free(str);
      }
   }

   err = LL_Destroy(c->messages);

   // Free client's other data
   client_data_destroy(c->data);
   
/*
   // FIXME?  Should the connection get closed here or elsewhere?
   if(c->sock) close(c->sock);
   c->sock = 0;
*/
   
   // Remove the client from the clients list...
   LL_Remove(clients, c);
   
   free(c);

   return 0;
}

// Add and remove messages from the client's queue...
int client_add_message(client *c, char *message)
{
   int err = 0;
   char *dup;
   char *str, *cp;
   char delimiters[] = "\n\r\0";
//   int len;

   //debug("client_add_message(%s)\n", message);
   
   if(!c) return -1;
   if(!message) return -1;

//   len = strlen(message);
//   if(len < 1) return 0;
   
   // Copy the string to avoid overwriting the original...
   dup = strdup(message);
   if(!dup)
   {
      fprintf(stderr, "client_add_message: Error allocating new string\n");
      return -1;
   }

   // Now split the string into lines and enqueue each one...
   for(str = strtok(dup, delimiters); str; str=strtok(NULL, delimiters))
   {
      cp = strdup(str);
      debug("client_add_message: %s\n", cp);
      err += LL_Enqueue(c->messages, (void *)cp);
   }

   //debug("client_add_message(%s): %i errors\n", message, err);
   free(dup);  // Fixed memory leak...
   
   // Err is the number of errors encountered...
   return err;
   
}
// Woo-hoo!  A simple function.  :)
char * client_get_message(client *c)
{
   char *str;

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

   if(!c) return NULL;
   
   str = (char *)LL_Dequeue(c->messages);

   //debug("client_get_message:  \"%s\"\n", str);
   
   return str;
}

// Get and set the client's data...
int client_set(client *c, void *data)
{
   // You know, I really doubt this function will be useful...
   return 0;
}
void * client_get(client *c)
{
   // But this one might be handy...

   return NULL;
}


client * client_find_sock(int sock)
{
   client * c;

//   debug("client_find_sock(%i)\n", sock);

   LL_Rewind(clients);
   do{
      c = (client *)LL_Get(clients);
//      debug("client_find_sock: ... %i ...\n", c->sock);
      if(c->sock == sock)
      {
//       debug("client_find_sock: ..! %i !..\n", c->sock);
         return c;
      }
   } while(LL_Next(clients) == 0);

   debug("client_find_sock: failed\n");
   
   return NULL;
}