local_locator.cpp

ACE自适配通信环境（ADAPTIVE Communication Environment）是可以自由使用、开放源码的面向对象（OO）框架（Framework）

// Local_Locator.cpp,v 1.7 1998/10/17 00:40:32 schmidt Exp

#if !defined (ACE_LOCAL_LOCATOR_C)
#define ACE_LOCAL_LOCATOR_C

#include "Local_Locator.h"

#if !defined (__ACE_INLINE__)
#include "Local_Locator.i"
#endif /* __ACE_INLINE__ */

ACE_RCSID(Caching, Local_Locator, "Local_Locator.cpp,v 1.7 1998/10/17 00:40:32 schmidt Exp")

int
ACE_URL_Local_Locator::url_query (const ACE_URL_Locator::ACE_Selection_Criteria how,
				  const ACE_URL_Property_Seq *pseq,
				  const size_t how_many,
				  size_t &num_query,
				  ACE_URL_Offer_Seq *offer)
{
  ACE_URL_Record *item = 0;

  ACE_NEW_RETURN (offer, ACE_URL_Offer_Seq (how_many), -1);
  
  if (how >= ACE_URL_Locator::INVALID_SELECTION)
    {
      errno = ACE_URL_Locator::INVALID_ARGUMENT;
      return -1;
    }
  
  num_query = 0;
  for (ACE_Unbounded_Set_Iterator<ACE_URL_Record> iter (this->repository_);
       iter.next (item) != 0;
       iter.advance ())
    {
      size_t i_query;
      size_t i_db;
      int found = 0;

      // Now this is a stupid implementation.  Perhaps we can
      // implement this using Hash_Map.  Better yet, I think we should
      // put this in a database and put SQL query here.
      for (i_query = 0; found == 0 && i_query < pseq->size (); i_query++)
	for (i_db = 0; i_db < item->offer_->url_properties ().size (); i_db++)
	  {
	    if ((*pseq)[i_query].name () == item->offer_->url_properties ()[i_db].name ())
	      if (how == ACE_URL_Locator::SOME)
                ;

      // if match and Some, copy to <offer>, inc <num_query>, advance iterator

      // else if All, advance iterator

      // else if None, check next property in <pseq>.

      if (all properties checked and found and ALL)
	copy to <offer>; inc <num_query>;
      else if (all properties checked and not found and NONE)
	copy to <offer>; inc <num_query>;
      else
	shouldn't happen, internal error

      if (num_query == how_many)
	break;
    }

  return 0;
}

int
ACE_URL_Local_Locator::export_offer (ACE_URL_Offer *offer,
				     ACE_WString &offer_id)
{
  ACE_URL_Record *item = 0;

  // First check if we have registered this URL already.
  for (ACE_Unbounded_Set_Iterator<ACE_URL_Record> iter (this->repository_);
       iter.next (item) != 0; 
       iter.advance ())
    if (*item->offer_->url () == *offer->url ())
      {
	errno = ACE_URL_Locator::OFFER_EXIST;
	return -1;
      }

  ACE_URL_Record *new_offer;

  // Offer is not in repository, we can add new one in safely.
  ACE_NEW_RETURN (new_offer, ACE_URL_Record (offer),
		  ACE_URL_Locator::NOMEM);

  this->repository_.push (*new_offer);

  offer_id = *new_offer->id_;
  return 0;
}

int
ACE_URL_Local_Locator::withdraw_offer (const ACE_WString &offer_id)
{
  ACE_URL_Record *item = 0;
  
  // Iterate thru repository and remove offer with <offer_id>.
  for (ACE_Unbounded_Set_Iterator<ACE_URL_Record> iter (this->repository_);
       iter.next (item) != 0;
       iter.advance ())
      if (offer_id == *item->id_)
	{
	  if (this->repository_.remove (*item) == 0)
	    return 0
	  else
	    {
	      errno = ACE_URL_Locator::UNKNOWN;
	      return -1;
	    }
	}

  errno = ACE_URL_Locator::NO_SUCH_OFFER;
  return 0;
}

int
ACE_URL_Local_Locator::describe_offer (const ACE_WString &offer_id,
				       ACE_URL_Offer *offer)
{
  ACE_URL_Record *item = 0;
  
  // Iterate thru the repository and produce a copy of offer's
  // description.
  for (ACE_Unbounded_Set_Iterator<ACE_URL_Record> iter (this->repository_);
       iter.next (item) != 0;
       iter.advance ())
    if (offer_id == *item->id_)
      {
	ACE_NEW_RETURN (offer, ACE_URL_Offer (*item->offer_), -1);
	return 0;
      }

  errno = ACE_URL_Locator::NO_SUCH_OFFER;
  return -1;
}

int
ACE_URL_Local_Locator::modify_offer (const ACE_WString &offer_id,
				     const ACE_WString *url,
				     const ACE_URL_Property_Seq *del,
				     const ACE_URL_Property_Seq *modify)
{
  ACE_Unbounded_Set_Iterator<ACE_URL_Record> iter (this->repository_);
  ACE_URL_Record *item = 0;
  ACE_URL_Record *target = 0;

  // Errno Checking

  for (; iter.next (item) != 0; iter.advance ())
    {
      if (url != 0 && *url == item->offer_->url ())
	{
	  errno = ACE_URL_Locator::OFFER_EXIST;
	  return -1;
	}
      if (offer_id == *item->id_)
	target = item;
    }	  

  if (target != 0)		// Aha, we found a target to work on
    {
      if (del != 0 && modify != 0)
	{
	  // We need to make a copy of the original property sequence
	  // so if any error occurs, we can revert our change easily.
	  
	  // First we need to calculate the maximum number of perperties.
	  int psize = target->offer_->url_properties ().size ();
	  if (del != 0)
	    if ((psize -= del->size ()) < 0)
	      {
		// If you try to delete more properties than we have,
		// you are doomed.  No need to proceed.
		errno = ACE_URL_Locator::INVALID_ARGUMENT;
		return -1;
	      }
	  if (modify != 0)
	    // In the worst case, all properties in <modify> will be added.
	    psize += modify->size ();

	  // Now, create a temporary work space.
	  ACE_URL_Property_Seq working (psize);
	  size_t sz = 0;
	  for (; sz < item->offer_->url_properties ().size ())
	    working[sz] = item->offer_->url_properties() [sz];

	  if (del != 0)
	    {
	      // Argh, this is really a stupid design.
	      // Go thru every property we want to delete
	      for (size_t i = 0; i < del->size () && sz > 0; i++)
		// For earch, go thru our property sequence and 
		// search for the property.
		for (size_t j = 0; j < sz; j++)
		  if ((*del)[i].name () == working[j].name ())
		    {
		      sz -= 1;
		      working[j] = working[sz]; // pack the array.
		      break;
		    }
	      // Doesn't generate error when we want to delete an
	      // imaginary property.  Is this appropriate?
	    }

	  if (modify != 0)
	    {
	      // This is also stupid.
	      // Go thru every property we want to modify/add
	      for (size_t i = 0; i < modify->size () && sz > 0; i++)
		{
		  // For each property, go thru our property list
		  // and search for the matching property
		  for (size_t j = 0; j < sz; j++)
		    if ((*modify)[i].name () == working[j].name ())
		      {
			// A match found.
			working[j].value ((*modify)[i].value ().fast_rep ());
			break;
		      }

		  // No matching property name were found,
		  // We want to add this property into the list.
		  if (j == sz)
		      working[sz++] = (*modify)[i];
		}
	    }
	}

      // Yes, all operations passed.  We can now copy the working version back.
      item->offer_->url_properties (ACE_URL_Property_Seq (sz));
      for (size_t i = 0; i < sz; i ++)
	item->offer_->url_properties ()[i] = working[i];

      if (url != 0)
	item->offer_->url (url->fast_rep ()); // replace URL location.
      return 0;
    }
  errno = ACE_URL_Locator::NO_SUCH_OFFER;
  return -1;
}

#if defined (ACE_HAS_EXPLICIT_TEMPLATE_INSTANTIATION)
template class ACE_Unbounded_Set<ACE_URL_Record>;
template class ACE_Unbounded_Set_Iterator<ACE_URL_Record>;
template class ACE_Node<ACE_URL_Record>;
#elif defined (ACE_HAS_TEMPLATE_INSTANTIATION_PRAGMA)
#pragma instantiate ACE_Unbounded_Set<ACE_URL_Record>
#pragma instantiate ACE_Unbounded_Set_Iterator<ACE_URL_Record>
#pragma instantiate ACE_Node<ACE_URL_Record>
#endif /*ACE_HAS_EXPLICIT_TEMPLATE_INSTANTIATION */
#endif /* ACE_LOCAL_LOCATOR_C */