Load cups into easysw/current.

[thirdparty/cups.git] / scheduler / filter.c

/*
 * "$Id: filter.c 4970 2006-01-24 14:05:45Z mike $"
 *
 *   File type conversion routines for the Common UNIX Printing System (CUPS).
 *
 *   Copyright 1997-2006 by Easy Software Products, all rights reserved.
 *
 *   These coded instructions, statements, and computer programs are the
 *   property of Easy Software Products and are protected by Federal
 *   copyright law.  Distribution and use rights are outlined in the file
 *   "LICENSE.txt" which should have been included with this file.  If this
 *   file is missing or damaged please contact Easy Software Products
 *   at:
 *
 *       Attn: CUPS Licensing Information
 *       Easy Software Products
 *       44141 Airport View Drive, Suite 204
 *       Hollywood, Maryland 20636 USA
 *
 *       Voice: (301) 373-9600
 *       EMail: cups-info@cups.org
 *         WWW: http://www.cups.org
 *
 * Contents:
 *
 *   mimeAddFilter()   - Add a filter to the current MIME database.
 *   mimeFilter()      - Find the fastest way to convert from one type to another.
 *   compare_filters() - Compare two filters...
 *   lookup()          - Lookup a filter...
 */

/*
 * Include necessary headers...
 */

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>

#include <cups/debug.h>
#include <cups/string.h>
#include "mime.h"


/*
 * Local functions...
 */

static int		compare_filters(mime_filter_t *, mime_filter_t *);
static mime_filter_t	*lookup(mime_t *, mime_type_t *, mime_type_t *);


/*
 * 'mimeAddFilter()' - Add a filter to the current MIME database.
 */

mime_filter_t *				/* O - New filter */
mimeAddFilter(mime_t      *mime,	/* I - MIME database */
              mime_type_t *src,		/* I - Source type */
	      mime_type_t *dst,		/* I - Destination type */
              int         cost,		/* I - Relative time/resource cost */
	      const char  *filter)	/* I - Filter program to run */
{
  mime_filter_t	*temp;			/* New filter */


 /*
  * Range-check the input...
  */

  if (!mime || !src || !dst || !filter)
    return (NULL);

 /*
  * See if we already have an existing filter for the given source and
  * destination...
  */

  if ((temp = lookup(mime, src, dst)) != NULL)
  {
   /*
    * Yup, does the existing filter have a higher cost?  If so, copy the
    * filter and cost to the existing filter entry and return it...
    */

    if (temp->cost > cost)
    {
      temp->cost = cost;
      strlcpy(temp->filter, filter, sizeof(temp->filter));
    }
  }
  else
  {
   /*
    * Nope, add a new one...
    */

    if (!mime->filters)
      mime->filters = cupsArrayNew((cups_array_func_t)compare_filters, NULL);

    if (!mime->filters)
      return (NULL);

    if ((temp = calloc(1, sizeof(mime_filter_t))) == NULL)
      return (NULL);

   /*
    * Copy the information over and sort if necessary...
    */

    temp->src  = src;
    temp->dst  = dst;
    temp->cost = cost;
    strlcpy(temp->filter, filter, sizeof(temp->filter));

    cupsArrayAdd(mime->filters, temp);
  }

 /*
  * Return the new/updated filter...
  */

  return (temp);
}


/*
 * 'mimeFilter()' - Find the fastest way to convert from one type to another.
 */

cups_array_t *				/* O - Array of filters to run */
mimeFilter(mime_t      *mime,		/* I - MIME database */
           mime_type_t *src,		/* I - Source file type */
	   mime_type_t *dst,		/* I - Destination file type */
	   int         *cost,		/* O - Cost of filters */
	   int         max_depth)       /* I - Maximum depth of search */
{
  int		tempcost,		/* Temporary cost */
		mincost;		/* Current minimum */
  cups_array_t	*temp,			/* Temporary filter */
		*mintemp;		/* Current minimum */
  mime_filter_t	*current;		/* Current filter */


 /*
  * Range-check the input...
  */

  DEBUG_printf(("mimeFilter(mime=%p, src=%p(%s/%s), dst=%p(%s/%s), "
                "cost=%p(%d), max_depth=%d)\n",
        	mime, src, src ? src->super : "?", src ? src->type : "?",
		dst, dst ? dst->super : "?", dst ? dst->type : "?",
		cost, cost ? *cost : 0, max_depth));

  if (cost)
    *cost = 0;

  if (!mime || !src || !dst || !cost || max_depth <= 0)
    return (NULL);

 /*
  * See if there is a filter that can convert the files directly...
  */

  if ((current = lookup(mime, src, dst)) != NULL)
  {
   /*
    * Got a direct filter!
    */

    if ((mintemp = cupsArrayNew(NULL, NULL)) == NULL)
      return (NULL);

    cupsArrayAdd(mintemp, current);

    mincost = current->cost;

    DEBUG_puts("    Found direct filter:");
    DEBUG_printf(("    %s (cost=%d)\n", mintemp->filter, mincost));
  }
  else
  {
   /*
    * No direct filter...
    */

    mintemp = NULL;
    mincost = 9999999;
  }

 /*
  * OK, now look for filters from the source type to any other type...
  */

  for (current = (mime_filter_t *)cupsArrayFirst(mime->filters);
       current;
       current = (mime_filter_t *)cupsArrayNext(mime->filters))
    if (current->src == src)
    {
     /*
      * See if we have any filters that can convert from the destination type
      * of this filter to the final type...
      */

      cupsArraySave(mime->filters);
      temp = mimeFilter(mime, current->dst, dst, &tempcost, max_depth - 1);
      cupsArrayRestore(mime->filters);

      if (!temp)
        continue;

     /*
      * Found a match; see if this one is less costly than the last (if
      * any...)
      */

      if (tempcost < mincost)
      {
        cupsArrayDelete(mintemp);

       /*
	* Hey, we got a match!  Add the current filter to the beginning of the
	* filter list...
	*/

        mintemp = temp;
	mincost = tempcost + current->cost;
	cupsArrayInsert(mintemp, current);
      }
      else
        cupsArrayDelete(temp);
    }

  if (mintemp)
  {
   /*
    * Hey, we got a match!
    */

#ifdef DEBUG
    printf("    Returning %d filters:\n", cupsArrayCount(mintemp));
    for (current = (mime_filter_t *)cupsArrayFirst(mintemp);
         current;
	 current = (mime_filter_t *)cupsArrayNext(mintemp))
      printf("    %s\n", current->filter);
#endif /* DEBUG */

    *cost = mincost;

    return (mintemp);
  }

  DEBUG_puts("    Returning zippo...");

  return (NULL);
}


/*
 * 'compare_filters()' - Compare two filters...
 */

static int				/* O - Comparison result */
compare_filters(mime_filter_t *f0,	/* I - First filter */
                mime_filter_t *f1)	/* I - Second filter */
{
  int	i;				/* Result of comparison */


  if ((i = strcmp(f0->src->super, f1->src->super)) == 0)
    if ((i = strcmp(f0->src->type, f1->src->type)) == 0)
      if ((i = strcmp(f0->dst->super, f1->dst->super)) == 0)
        i = strcmp(f0->dst->type, f1->dst->type);

  return (i);
}


/*
 * 'lookup()' - Lookup a filter...
 */

static mime_filter_t *			/* O - Filter for src->dst */
lookup(mime_t      *mime,		/* I - MIME database */
       mime_type_t *src,		/* I - Source type */
       mime_type_t *dst)		/* I - Destination type */
{
  mime_filter_t	key;			/* Key record for filter search */


  key.src = src;
  key.dst = dst;

  return ((mime_filter_t *)cupsArrayFind(mime->filters, &key));
}


/*
 * End of "$Id: filter.c 4970 2006-01-24 14:05:45Z mike $".
 */