download.c

prozgui是一款Linxu下著名的下载工具

	  int server_pos, cur_path_pos;

	  server_pos =
	      ftpsearch_get_server_position(download->ftps_info,
					    download->pconnections[i]->u.
					    host);
	  cur_path_pos =
	      ftpsearch_get_path_position(download->ftps_info,
					  download->pconnections[i]->u.host,
					  download->pconnections[i]->u.dir);
	  assert(cur_path_pos != -1);

	  proz_debug("Server pos = %d, cur_path_pos=%d", server_pos,
		     cur_path_pos);
	  /*mark path as not valid */
	  download->ftps_info->mirrors[server_pos].paths[cur_path_pos].
	      valid = FALSE;

	  /*See if more paths are avail */ ;
	  if (cur_path_pos <
	      (download->ftps_info->mirrors[server_pos].num_paths - 1))
	  {
	    char *url_buf;

	    /* Make sure this thread has terminated */
	    pthread_join(download->threads[i], NULL);
	    /*additional paths avail to try */

	    download_show_message(download,
				  _
				  ("Trying additional paths available on this server"));
	    proz_debug("Trying path %s",
		       download->ftps_info->mirrors[server_pos].
		       paths[cur_path_pos + 1]);

	    url_buf =
		malloc(strlen
		       (download->ftps_info->mirrors[server_pos].
			server_name) +
		       strlen(download->ftps_info->mirrors[server_pos].
			      paths[cur_path_pos + 1].path) +
		       strlen(download->pconnections[i]->u.file) + 11 + 1);

	    sprintf(url_buf, "ftp://%s/%s/%s",
		    download->ftps_info->mirrors[server_pos].server_name,
		    download->ftps_info->mirrors[server_pos].
		    paths[cur_path_pos + 1].path,
		    download->pconnections[i]->u.file);

	    proz_debug("Target url for relaunching is %s", url_buf);
	    /*FIXME */
	    proz_parse_url(url_buf, &download->pconnections[i]->u, 0);
	    free(url_buf);

	    /*Relaunch thread */
	    if (pthread_create
		(&download->threads[i], NULL, (void *) &ftp_loop,
		 (void *) (download->pconnections[i])) != 0)
	      proz_die(_("Error: Not enough system resources"));
	  } else
	  {
	    int j, usable_server;
	    /*download_show_message(download,
	       _
	       ("No additional paths on this server available, so will try to switch to another server")); */
	    /*Find any server that is downloading or completed and use it */

	    usable_server = -1;

	    pthread_mutex_lock(&download->status_change_mutex);
	    for (j = 0; j < download->num_connections; j++)
	    {
	      if (download->pconnections[j]->status == DOWNLOADING ||
		  download->pconnections[j]->status == COMPLETED)
	      {
		usable_server = j;
	      }
	    }
	    pthread_mutex_unlock(&download->status_change_mutex);

	    if (usable_server != -1)
	    {
	      /*We have a server which is DLING */
	      download_show_message(download,
				    _
				    ("No additional paths on this server available, so will switch to another server"));
	      /* Make sure this thread has terminated */
	      pthread_join(download->threads[i], NULL);

	      /*copy url and relaunch */
	      proz_free_url(&download->pconnections[i]->u, 0);
	      memcpy(&download->pconnections[i]->u,
		     proz_copy_url(&download->
				   pconnections[usable_server]->u),
		     sizeof(urlinfo));
	      proz_debug
		  ("Found server %s which is downloading will relaunch based on it",
		   download->pconnections[usable_server]->u.host);

	      /*Relaunch thread */
	      if (pthread_create
		  (&download->threads[i], NULL, (void *) &ftp_loop,
		   (void *) (download->pconnections[i])) != 0)
		proz_die(_("Error: Not enough system resources"));

	    } else
	    {
	      /*Shit! no servers are downloading so what shall we do? we shall do nothing and wait for one connectection at least to start downloading */

	    }
	  }
	}
      } else /*Handle the file not being found on the server */
	if (connection_err == FTPCWDFAIL)
      {
	if (proz_download_all_dls_ftpcwdfail(download) == TRUE)
	{
	  download_show_message(download,
				_
				("Failed to change to the working directory on all the connections!"));
	  /*Terminate the connections */
	  proz_download_stop_downloads(download);
	  return DLREMOTEFATAL;
	} else
	{

	  /*Now we have to be careful */
	  int server_pos, cur_path_pos;

	  server_pos =
	      ftpsearch_get_server_position(download->ftps_info,
					    download->pconnections[i]->u.
					    host);
	  assert(server_pos != -1);
	  cur_path_pos =
	      ftpsearch_get_path_position(download->ftps_info,
					  download->pconnections[i]->u.host,
					  download->pconnections[i]->u.dir);
	  assert(cur_path_pos != -1);

	  proz_debug("Server pos = %d, cur_path_pos=%d", server_pos,
		     cur_path_pos);

	  /*mark path as not valid */
	  download->ftps_info->mirrors[server_pos].paths[cur_path_pos].
	      valid = FALSE;
	  /*See if more paths are avail */ ;
	  if (cur_path_pos <
	      (download->ftps_info->mirrors[server_pos].num_paths - 1))
	  {
	    char *url_buf;

	    /* Make sure this thread has terminated */
	    pthread_join(download->threads[i], NULL);
	    /*additional paths avail to try */

	    download_show_message(download,
				  _
				  ("Trying additional paths available on this server"));
	    proz_debug("Trying path %s",
		       download->ftps_info->mirrors[server_pos].
		       paths[cur_path_pos + 1]);

	    url_buf =
		malloc(strlen
		       (download->ftps_info->mirrors[server_pos].
			server_name) +
		       strlen(download->ftps_info->mirrors[server_pos].
			      paths[cur_path_pos + 1].path) +
		       strlen(download->pconnections[i]->u.file) + 11 + 1);

	    sprintf(url_buf, "ftp://%s/%s/%s",
		    download->ftps_info->mirrors[server_pos].server_name,
		    download->ftps_info->mirrors[server_pos].
		    paths[cur_path_pos + 1].path,
		    download->pconnections[i]->u.file);

	    proz_debug("Target url for relaunching is %s", url_buf);
	    /*FIXME */
	    proz_parse_url(url_buf, &download->pconnections[i]->u, 0);
	    free(url_buf);

	    /*Relaunch thread */
	    if (pthread_create
		(&download->threads[i], NULL, (void *) &ftp_loop,
		 (void *) (download->pconnections[i])) != 0)
	      proz_die(_("Error: Not enough system resources"));
	  } else
	  {
	    int j, usable_server;
	    /*      download_show_message(download, _("No additional paths on this server available, so will try to switch to another server")); */

	    proz_debug
		("No additional paths on this server available, so will try to switch to another server");
	    /*Find any server that is downloading or completed and use it */

	    usable_server = -1;

	    pthread_mutex_lock(&download->status_change_mutex);
	    for (j = 0; j < download->num_connections; j++)
	    {
	      if (download->pconnections[j]->status == DOWNLOADING ||
		  download->pconnections[j]->status == COMPLETED)
	      {
		usable_server = j;
	      }
	    }
	    pthread_mutex_unlock(&download->status_change_mutex);

	    if (usable_server != -1)
	    {
	      /*We have a server which is DLING */
	      download_show_message(download,
				    _
				    ("No additional paths on this server available, so will switch to another server"));
	      /* Make sure this thread has terminated */
	      pthread_join(download->threads[i], NULL);

	      /*copy url and relaunch */
	      proz_free_url(&download->pconnections[i]->u, 0);
	      memcpy(&download->pconnections[i]->u,
		     proz_copy_url(&download->
				   pconnections[usable_server]->u),
		     sizeof(urlinfo));

	      proz_debug
		  ("Found server %s which is downloading will relaunch based on it",
		   download->pconnections[usable_server]->u.host);

	      /*Relaunch thread */
	      if (pthread_create
		  (&download->threads[i], NULL, (void *) &ftp_loop,
		   (void *) (download->pconnections[i])) != 0)
		proz_die(_("Error: Not enough system resources"));

	    } else
	    {
	      /*Shit! no servers are downloading so what shall we do? we shall do nothing and wait for one connectection at least to start downloading */

	    }
	  }
	}
      } else if (connection_err == FTPRESTFAIL)
      {
	/*Handle the server not supporting REST */
	if (proz_download_all_dls_err(download, FTPRESTFAIL) == TRUE)
	{
	  download_show_message(download,
				_
				("The server(s) do not support  REST on all the connections!"));
	  /*Terminate the connections */
	  proz_download_stop_downloads(download);
	  return DLREMOTEFATAL;
	} else
	{

	  /*Now we have to be careful */
	  int server_pos;

	  server_pos =
	      ftpsearch_get_server_position(download->ftps_info,
					    download->pconnections[i]->u.
					    host);

	  proz_debug("Server pos = %d", server_pos);
	  /*mark server as not supporting resume */
	  download->ftps_info->mirrors[server_pos].resume_supported =
	      FALSE;

	  {
	    int j, usable_server;

	    /*Find any server that is downloading or completed and use it instead */

	    usable_server = -1;

	    pthread_mutex_lock(&download->status_change_mutex);
	    for (j = 0; j < download->num_connections; j++)
	    {
	      if (download->pconnections[j]->status == DOWNLOADING ||
		  download->pconnections[j]->status == COMPLETED)
	      {
		usable_server = j;
	      }
	    }
	    pthread_mutex_unlock(&download->status_change_mutex);

	    if (usable_server != -1)
	    {
	      /*We have a server which is DLING */
	      download_show_message(download,
				    _
				    ("This server does not support resuming downloads, so will switch to another server"));
	      /* Make sure this thread has terminated */
	      pthread_join(download->threads[i], NULL);

	      /*copy url and relaunch */
	      proz_free_url(&download->pconnections[i]->u, 0);
	      memcpy(&download->pconnections[i]->u,
		     proz_copy_url(&download->
				   pconnections[usable_server]->u),
		     sizeof(urlinfo));
	      proz_debug
		  ("Found server %s which is downloading will relaunch based on it",
		   download->pconnections[usable_server]->u.host);

	      /*Relaunch thread */
	      if (pthread_create
		  (&download->threads[i], NULL, (void *) &ftp_loop,
		   (void *) (download->pconnections[i])) != 0)
		proz_die(_("Error: Not enough system resources"));

	    } else
	    {
	      /*Shit! no servers are downloading so what shall we do? we shall do nothing and wait for one connectection at least to start downloading */

	    }
	  }
	}
      }

      break;

    case LOCALFATAL:
      proz_download_stop_downloads(download);
      download_show_message(download,
			    _
			    ("Connection %d, had a local fatal error: %s .Aborting download. "),
			    i,
			    proz_strerror(download->pconnections[i]->err));
      return DLLOCALFATAL;
      break;

    case LOGINFAIL:
      /*
       * First check if the ftp server did not allow any thread 
       * to login at all, then  retry the curent thread 
       */
      if (proz_download_all_dls_status(download, LOGINFAIL) == TRUE)
      {
	download_show_message(download,
			      _
			      ("All logins rejected! Retrying connection"));
	/* Make sure this thread has terminated */
	pthread_join(download->threads[i], NULL);

	if (pthread_create
	    (&download->threads[i], NULL, (void *) &ftp_loop,
	     (void *) (download->pconnections[i])) != 0)
	  proz_die(_("Error: Not enough system resources"));

	break;
      } else
      {

	    int j, usable_server;

	    /*Find any server that is downloading or completed and use it instead */

	    usable_server = -1;

	    pthread_mutex_lock(&download->status_change_mutex);
	    for (j = 0; j < download->num_connections; j++)
	    {
	      if ((download->pconnections[j]->status == DOWNLOADING ||
		  download->pconnections[j]->status == COMPLETED) && j!=i)
	      {
		usable_server = j;
	      }
	    }
	    pthread_mutex_unlock(&download->status_change_mutex);

	    if (usable_server != -1)
	    {
	      /*We have a server which is DLING */
	      download_show_message(download,
				    _
				    ("This server has rejected the login attempt, so will switch to another server"));
	      /* Make sure this thread has terminated */
	      pthread_join(download->threads[i], NULL);

	      /*copy url and relaunch */
	      proz_free_url(&download->pconnections[i]->u, 0);
	      memcpy(&download->pconnections[i]->u,
		     proz_copy_url(&download->
				   pconnections[usable_server]->u),
		     sizeof(urlinfo));
	      proz_debug
		  ("Found server %s which is downloading will relaunch based on it",
		   download->pconnections[usable_server]->u.host);

	      /*Relaunch thread */
	      if (pthread_create
		  (&download->threads[i], NULL, (void *) &ftp_loop,
		   (void *) (download->pconnections[i])) != 0)
		proz_die(_("Error: Not enough system resources"));

	    } else
	    {
	     
	/*
	 * Ok so at least there is one download whos login has not been rejected, 
	 * so lets see if it has completed, if so we can relaunch this connection, 
	 * as the commonest reason for a ftp login being rejected is because, the 
	 * ftp server has a limit on the number of logins permitted from the same 
	 * IP address. 
	 */

	/*
	 * Query the number of threads that are downloading 
	 * if it is zero then relaunch this connection
	 */
	int server_pos;
	int dling_conns_count =
	    download_query_conns_status_count(download, DOWNLOADING,
					      download->
					      pconnections[i]->u.host);

	server_pos =
	    ftpsearch_get_server_position(download->ftps_info,
					  download->pconnections[i]->u.host);

	if (dling_conns_count >
	    download->ftps_info->mirrors[server_pos].max_simul_connections)
	{
	  download->ftps_info->mirrors[server_pos].max_simul_connections =
	      dling_conns_count;
	  break;
	}


	if (dling_conns_count == 0
	    &&
	    (download_query_conns_status_count
	     (download, CONNECTING, download->pconnections[i]->u.host) == 0)
	    &&
	    (download_query_conns_status_count
	     (download, LOGGININ, download->pconnections[i]->u.host) == 0))
	{

	  /* Make sure this thread has terminated */
	  pthread_join(download->threads[i], NULL);
	  pthread_mutex_lock(&download->status_change_mutex);