[thirdparty/cups.git] / cups / ppd-conflicts.c

/*
 * Option conflict management routines for CUPS.
 *
 * Copyright 2007-2018 by Apple Inc.
 * Copyright 1997-2007 by Easy Software Products, all rights reserved.
 *
 * Licensed under Apache License v2.0.  See the file "LICENSE" for more
 * information.
 *
 * PostScript is a trademark of Adobe Systems, Inc.
 */

/*
 * Include necessary headers...
 */

#include "cups-private.h"
#include "ppd-private.h"


/*
 * Local constants...
 */

enum
{
  _PPD_OPTION_CONSTRAINTS,
  _PPD_INSTALLABLE_CONSTRAINTS,
  _PPD_ALL_CONSTRAINTS
};


/*
 * Local functions...
 */

static int              ppd_is_installable(ppd_group_t *installable,
                                           const char *option);
static void             ppd_load_constraints(ppd_file_t *ppd);
static cups_array_t     *ppd_test_constraints(ppd_file_t *ppd,
                                              const char *option,
                                              const char *choice,
                                              int num_options,
                                              cups_option_t *options,
                                              int which);


/*
 * 'cupsGetConflicts()' - Get a list of conflicting options in a marked PPD.
 *
 * This function gets a list of options that would conflict if "option" and
 * "choice" were marked in the PPD.  You would typically call this function
 * after marking the currently selected options in the PPD in order to
 * determine whether a new option selection would cause a conflict.
 *
 * The number of conflicting options are returned with "options" pointing to
 * the conflicting options.  The returned option array must be freed using
 * @link cupsFreeOptions@.
 *
 * @since CUPS 1.4/macOS 10.6@
 */

int                                     /* O - Number of conflicting options */
cupsGetConflicts(
    ppd_file_t    *ppd,                 /* I - PPD file */
    const char    *option,              /* I - Option to test */
    const char    *choice,              /* I - Choice to test */
    cups_option_t **options)            /* O - Conflicting options */
{
  int                   i,              /* Looping var */
                        num_options;    /* Number of conflicting options */
  cups_array_t          *active;        /* Active conflicts */
  _ppd_cups_uiconsts_t  *c;             /* Current constraints */
  _ppd_cups_uiconst_t   *cptr;          /* Current constraint */
  ppd_choice_t          *marked;        /* Marked choice */


 /*
  * Range check input...
  */

  if (options)
    *options = NULL;

  if (!ppd || !option || !choice || !options)
    return (0);

 /*
  * Test for conflicts...
  */

  active = ppd_test_constraints(ppd, option, choice, 0, NULL,
                                _PPD_ALL_CONSTRAINTS);

 /*
  * Loop through all of the UI constraints and add any options that conflict...
  */

  for (num_options = 0, c = (_ppd_cups_uiconsts_t *)cupsArrayFirst(active);
       c;
       c = (_ppd_cups_uiconsts_t *)cupsArrayNext(active))
  {
    for (i = c->num_constraints, cptr = c->constraints;
         i > 0;
         i --, cptr ++)
      if (_cups_strcasecmp(cptr->option->keyword, option))
      {
        if (cptr->choice)
          num_options = cupsAddOption(cptr->option->keyword,
                                      cptr->choice->choice, num_options,
                                      options);
        else if ((marked = ppdFindMarkedChoice(ppd,
                                               cptr->option->keyword)) != NULL)
          num_options = cupsAddOption(cptr->option->keyword, marked->choice,
                                      num_options, options);
      }
  }

  cupsArrayDelete(active);

  return (num_options);
}


/*
 * 'cupsResolveConflicts()' - Resolve conflicts in a marked PPD.
 *
 * This function attempts to resolve any conflicts in a marked PPD, returning
 * a list of option changes that are required to resolve them.  On input,
 * "num_options" and "options" contain any pending option changes that have
 * not yet been marked, while "option" and "choice" contain the most recent
 * selection which may or may not be in "num_options" or "options".
 *
 * On successful return, "num_options" and "options" are updated to contain
 * "option" and "choice" along with any changes required to resolve conflicts
 * specified in the PPD file and 1 is returned.
 *
 * If option conflicts cannot be resolved, "num_options" and "options" are not
 * changed and 0 is returned.
 *
 * When resolving conflicts, @code cupsResolveConflicts@ does not consider
 * changes to the current page size (@code media@, @code PageSize@, and
 * @code PageRegion@) or to the most recent option specified in "option".
 * Thus, if the only way to resolve a conflict is to change the page size
 * or the option the user most recently changed, @code cupsResolveConflicts@
 * will return 0 to indicate it was unable to resolve the conflicts.
 *
 * The @code cupsResolveConflicts@ function uses one of two sources of option
 * constraint information.  The preferred constraint information is defined by
 * @code cupsUIConstraints@ and @code cupsUIResolver@ attributes - in this
 * case, the PPD file provides constraint resolution actions.
 *
 * The backup constraint information is defined by the
 * @code UIConstraints@ and @code NonUIConstraints@ attributes.  These
 * constraints are resolved algorithmically by first selecting the default
 * choice for the conflicting option, then iterating over all possible choices
 * until a non-conflicting option choice is found.
 *
 * @since CUPS 1.4/macOS 10.6@
 */

int                                     /* O  - 1 on success, 0 on failure */
cupsResolveConflicts(
    ppd_file_t    *ppd,                 /* I  - PPD file */
    const char    *option,              /* I  - Newly selected option or @code NULL@ for none */
    const char    *choice,              /* I  - Newly selected choice or @code NULL@ for none */
    int           *num_options,         /* IO - Number of additional selected options */
    cups_option_t **options)            /* IO - Additional selected options */
{
  int                   i,              /* Looping var */
                        tries,          /* Number of tries */
                        num_newopts;    /* Number of new options */
  cups_option_t         *newopts;       /* New options */
  cups_array_t          *active = NULL, /* Active constraints */
                        *pass,          /* Resolvers for this pass */
                        *resolvers,     /* Resolvers we have used */
                        *test;          /* Test array for conflicts */
  _ppd_cups_uiconsts_t  *consts;        /* Current constraints */
  _ppd_cups_uiconst_t   *constptr;      /* Current constraint */
  ppd_attr_t            *resolver;      /* Current resolver */
  const char            *resval;        /* Pointer into resolver value */
  char                  resoption[PPD_MAX_NAME],
                                        /* Current resolver option */
                        reschoice[PPD_MAX_NAME],
                                        /* Current resolver choice */
                        *resptr,        /* Pointer into option/choice */
                        firstpage[255]; /* AP_FIRSTPAGE_Keyword string */
  const char            *value;         /* Selected option value */
  int                   changed;        /* Did we change anything? */
  ppd_choice_t          *marked;        /* Marked choice */


 /*
  * Range check input...
  */

  if (!ppd || !num_options || !options || (option == NULL) != (choice == NULL))
    return (0);

 /*
  * Build a shadow option array...
  */

  num_newopts = 0;
  newopts     = NULL;

  for (i = 0; i < *num_options; i ++)
    num_newopts = cupsAddOption((*options)[i].name, (*options)[i].value,
                                num_newopts, &newopts);
  if (option && _cups_strcasecmp(option, "Collate"))
    num_newopts = cupsAddOption(option, choice, num_newopts, &newopts);

 /*
  * Loop until we have no conflicts...
  */

  cupsArraySave(ppd->sorted_attrs);

  resolvers = NULL;
  pass      = cupsArrayNew((cups_array_func_t)_cups_strcasecmp, NULL);
  tries     = 0;

  while (tries < 100 &&
         (active = ppd_test_constraints(ppd, NULL, NULL, num_newopts, newopts,
                                        _PPD_ALL_CONSTRAINTS)) != NULL)
  {
    tries ++;

    if (!resolvers)
      resolvers = cupsArrayNew((cups_array_func_t)_cups_strcasecmp, NULL);

    for (consts = (_ppd_cups_uiconsts_t *)cupsArrayFirst(active), changed = 0;
         consts;
         consts = (_ppd_cups_uiconsts_t *)cupsArrayNext(active))
    {
      if (consts->resolver[0])
      {
       /*
        * Look up the resolver...
        */

        if (cupsArrayFind(pass, consts->resolver))
          continue;                     /* Already applied this resolver... */

        if (cupsArrayFind(resolvers, consts->resolver))
        {
         /*
          * Resolver loop!
          */

          DEBUG_printf(("1cupsResolveConflicts: Resolver loop with %s!",
                        consts->resolver));
          goto error;
        }

        if ((resolver = ppdFindAttr(ppd, "cupsUIResolver",
                                    consts->resolver)) == NULL)
        {
          DEBUG_printf(("1cupsResolveConflicts: Resolver %s not found!",
                        consts->resolver));
          goto error;
        }

        if (!resolver->value)
        {
          DEBUG_printf(("1cupsResolveConflicts: Resolver %s has no value!",
                        consts->resolver));
          goto error;
        }

       /*
        * Add the options from the resolver...
        */

        cupsArrayAdd(pass, consts->resolver);
        cupsArrayAdd(resolvers, consts->resolver);

        for (resval = resolver->value; *resval && !changed;)
        {
          while (_cups_isspace(*resval))
            resval ++;

          if (*resval != '*')
            break;

          for (resval ++, resptr = resoption;
               *resval && !_cups_isspace(*resval);
               resval ++)
            if (resptr < (resoption + sizeof(resoption) - 1))
              *resptr++ = *resval;

          *resptr = '\0';

          while (_cups_isspace(*resval))
            resval ++;

          for (resptr = reschoice;
               *resval && !_cups_isspace(*resval);
               resval ++)
            if (resptr < (reschoice + sizeof(reschoice) - 1))
              *resptr++ = *resval;

          *resptr = '\0';

          if (!resoption[0] || !reschoice[0])
            break;

         /*
          * Is this the option we are changing?
          */

          snprintf(firstpage, sizeof(firstpage), "AP_FIRSTPAGE_%s", resoption);

          if (option &&
              (!_cups_strcasecmp(resoption, option) ||
               !_cups_strcasecmp(firstpage, option) ||
               (!_cups_strcasecmp(option, "PageSize") &&
                !_cups_strcasecmp(resoption, "PageRegion")) ||
               (!_cups_strcasecmp(option, "AP_FIRSTPAGE_PageSize") &&
                !_cups_strcasecmp(resoption, "PageSize")) ||
               (!_cups_strcasecmp(option, "AP_FIRSTPAGE_PageSize") &&
                !_cups_strcasecmp(resoption, "PageRegion")) ||
               (!_cups_strcasecmp(option, "PageRegion") &&
                !_cups_strcasecmp(resoption, "PageSize")) ||
               (!_cups_strcasecmp(option, "AP_FIRSTPAGE_PageRegion") &&
                !_cups_strcasecmp(resoption, "PageSize")) ||
               (!_cups_strcasecmp(option, "AP_FIRSTPAGE_PageRegion") &&
                !_cups_strcasecmp(resoption, "PageRegion"))))
            continue;

         /*
          * Try this choice...
          */

          if ((test = ppd_test_constraints(ppd, resoption, reschoice,
                                           num_newopts, newopts,
                                           _PPD_ALL_CONSTRAINTS)) == NULL)
          {
           /*
            * That worked...
            */

            changed = 1;
          }
          else
            cupsArrayDelete(test);

         /*
          * Add the option/choice from the resolver regardless of whether it
          * worked; this makes sure that we can cascade several changes to
          * make things resolve...
          */

          num_newopts = cupsAddOption(resoption, reschoice, num_newopts,
                                      &newopts);
        }
      }
      else
      {
       /*
        * Try resolving by choosing the default values for non-installable
        * options, then by iterating through the possible choices...
        */

        int             j;              /* Looping var */
        ppd_choice_t    *cptr;          /* Current choice */
        ppd_size_t      *size;          /* Current page size */


        for (i = consts->num_constraints, constptr = consts->constraints;
             i > 0 && !changed;
             i --, constptr ++)
        {
         /*
          * Can't resolve by changing an installable option...
          */

          if (constptr->installable)
            continue;

         /*
          * Is this the option we are changing?
          */

          if (option &&
              (!_cups_strcasecmp(constptr->option->keyword, option) ||
               (!_cups_strcasecmp(option, "PageSize") &&
                !_cups_strcasecmp(constptr->option->keyword, "PageRegion")) ||
               (!_cups_strcasecmp(option, "PageRegion") &&
                !_cups_strcasecmp(constptr->option->keyword, "PageSize"))))
            continue;

         /*
          * Get the current option choice...
          */

          if ((value = cupsGetOption(constptr->option->keyword, num_newopts,
                                     newopts)) == NULL)
          {
            if (!_cups_strcasecmp(constptr->option->keyword, "PageSize") ||
                !_cups_strcasecmp(constptr->option->keyword, "PageRegion"))
            {
              if ((value = cupsGetOption("PageSize", num_newopts,
                                         newopts)) == NULL)
                value = cupsGetOption("PageRegion", num_newopts, newopts);

              if (!value)
              {
                if ((size = ppdPageSize(ppd, NULL)) != NULL)
                  value = size->name;
                else
                  value = "";
              }
            }
            else
            {
              marked = ppdFindMarkedChoice(ppd, constptr->option->keyword);
              value  = marked ? marked->choice : "";
            }
          }

          if (!_cups_strncasecmp(value, "Custom.", 7))
            value = "Custom";

         /*
          * Try the default choice...
          */

          test = NULL;

          if (_cups_strcasecmp(value, constptr->option->defchoice) &&
              (test = ppd_test_constraints(ppd, constptr->option->keyword,
                                           constptr->option->defchoice,
                                           num_newopts, newopts,
                                           _PPD_OPTION_CONSTRAINTS)) == NULL)
          {
           /*
            * That worked...
            */

            num_newopts = cupsAddOption(constptr->option->keyword,
                                        constptr->option->defchoice,
                                        num_newopts, &newopts);
            changed     = 1;
          }
          else
          {
           /*
            * Try each choice instead...
            */

            for (j = constptr->option->num_choices,
                     cptr = constptr->option->choices;
                 j > 0;
                 j --, cptr ++)
            {
              cupsArrayDelete(test);
              test = NULL;

              if (_cups_strcasecmp(value, cptr->choice) &&
                  _cups_strcasecmp(constptr->option->defchoice, cptr->choice) &&
                  _cups_strcasecmp("Custom", cptr->choice) &&
                  (test = ppd_test_constraints(ppd, constptr->option->keyword,
                                               cptr->choice, num_newopts,
                                               newopts,
                                               _PPD_OPTION_CONSTRAINTS)) == NULL)
              {
               /*
                * This choice works...
                */

                num_newopts = cupsAddOption(constptr->option->keyword,
                                            cptr->choice, num_newopts,
                                            &newopts);
                changed     = 1;
                break;
              }
            }

            cupsArrayDelete(test);
          }
        }
      }
    }

    if (!changed)
    {
      DEBUG_puts("1cupsResolveConflicts: Unable to automatically resolve "
                 "constraint!");
      goto error;
    }

    cupsArrayClear(pass);
    cupsArrayDelete(active);
    active = NULL;
  }

  if (tries >= 100)
    goto error;

 /*
  * Free the caller's option array...
  */

  cupsFreeOptions(*num_options, *options);

 /*
  * If Collate is the option we are testing, add it here.  Otherwise, remove
  * any Collate option from the resolve list since the filters automatically
  * handle manual collation...
  */

  if (option && !_cups_strcasecmp(option, "Collate"))
    num_newopts = cupsAddOption(option, choice, num_newopts, &newopts);
  else
    num_newopts = cupsRemoveOption("Collate", num_newopts, &newopts);

 /*
  * Return the new list of options to the caller...
  */

  *num_options = num_newopts;
  *options     = newopts;

  cupsArrayDelete(pass);
  cupsArrayDelete(resolvers);

  cupsArrayRestore(ppd->sorted_attrs);

  DEBUG_printf(("1cupsResolveConflicts: Returning %d options:", num_newopts));
#ifdef DEBUG
  for (i = 0; i < num_newopts; i ++)
    DEBUG_printf(("1cupsResolveConflicts: options[%d]: %s=%s", i,
                  newopts[i].name, newopts[i].value));
#endif /* DEBUG */

  return (1);

 /*
  * If we get here, we failed to resolve...
  */

  error:

  cupsFreeOptions(num_newopts, newopts);

  cupsArrayDelete(active);
  cupsArrayDelete(pass);
  cupsArrayDelete(resolvers);

  cupsArrayRestore(ppd->sorted_attrs);

  DEBUG_puts("1cupsResolveConflicts: Unable to resolve conflicts!");

  return (0);
}


/*
 * 'ppdConflicts()' - Check to see if there are any conflicts among the
 *                    marked option choices.
 *
 * The returned value is the same as returned by @link ppdMarkOption@.
 */

int                                     /* O - Number of conflicts found */
ppdConflicts(ppd_file_t *ppd)           /* I - PPD to check */
{
  int                   i,              /* Looping variable */
                        conflicts;      /* Number of conflicts */
  cups_array_t          *active;        /* Active conflicts */
  _ppd_cups_uiconsts_t  *c;             /* Current constraints */
  _ppd_cups_uiconst_t   *cptr;          /* Current constraint */
  ppd_option_t  *o;                     /* Current option */


  if (!ppd)
    return (0);

 /*
  * Clear all conflicts...
  */

  cupsArraySave(ppd->options);

  for (o = ppdFirstOption(ppd); o; o = ppdNextOption(ppd))
    o->conflicted = 0;

  cupsArrayRestore(ppd->options);

 /*
  * Test for conflicts...
  */

  active    = ppd_test_constraints(ppd, NULL, NULL, 0, NULL,
                                   _PPD_ALL_CONSTRAINTS);
  conflicts = cupsArrayCount(active);

 /*
  * Loop through all of the UI constraints and flag any options
  * that conflict...
  */

  for (c = (_ppd_cups_uiconsts_t *)cupsArrayFirst(active);
       c;
       c = (_ppd_cups_uiconsts_t *)cupsArrayNext(active))
  {
    for (i = c->num_constraints, cptr = c->constraints;
         i > 0;
         i --, cptr ++)
      cptr->option->conflicted = 1;
  }

  cupsArrayDelete(active);

 /*
  * Return the number of conflicts found...
  */

  return (conflicts);
}


/*
 * 'ppdInstallableConflict()' - Test whether an option choice conflicts with
 *                              an installable option.
 *
 * This function tests whether a particular option choice is available based
 * on constraints against options in the "InstallableOptions" group.
 *
 * @since CUPS 1.4/macOS 10.6@
 */

int                                     /* O - 1 if conflicting, 0 if not conflicting */
ppdInstallableConflict(
    ppd_file_t *ppd,                    /* I - PPD file */
    const char *option,                 /* I - Option */
    const char *choice)                 /* I - Choice */
{
  cups_array_t  *active;                /* Active conflicts */


  DEBUG_printf(("2ppdInstallableConflict(ppd=%p, option=\"%s\", choice=\"%s\")",
                ppd, option, choice));

 /*
  * Range check input...
  */

  if (!ppd || !option || !choice)
    return (0);

 /*
  * Test constraints using the new option...
  */

  active = ppd_test_constraints(ppd, option, choice, 0, NULL,
                                _PPD_INSTALLABLE_CONSTRAINTS);

  cupsArrayDelete(active);

  return (active != NULL);
}


/*
 * 'ppd_is_installable()' - Determine whether an option is in the
 *                          InstallableOptions group.
 */

static int                              /* O - 1 if installable, 0 if normal */
ppd_is_installable(
    ppd_group_t *installable,           /* I - InstallableOptions group */
    const char  *name)                  /* I - Option name */
{
  if (installable)
  {
    int                 i;              /* Looping var */
    ppd_option_t        *option;        /* Current option */


    for (i = installable->num_options, option = installable->options;
         i > 0;
         i --, option ++)
      if (!_cups_strcasecmp(option->keyword, name))
        return (1);
  }

  return (0);
}


/*
 * 'ppd_load_constraints()' - Load constraints from a PPD file.
 */

static void
ppd_load_constraints(ppd_file_t *ppd)   /* I - PPD file */
{
  int           i;                      /* Looping var */
  ppd_const_t   *oldconst;              /* Current UIConstraints data */
  ppd_attr_t    *constattr;             /* Current cupsUIConstraints attribute */
  _ppd_cups_uiconsts_t  *consts;        /* Current cupsUIConstraints data */
  _ppd_cups_uiconst_t   *constptr;      /* Current constraint */
  ppd_group_t   *installable;           /* Installable options group */
  const char    *vptr;                  /* Pointer into constraint value */
  char          option[PPD_MAX_NAME],   /* Option name/MainKeyword */
                choice[PPD_MAX_NAME],   /* Choice/OptionKeyword */
                *ptr;                   /* Pointer into option or choice */


  DEBUG_printf(("7ppd_load_constraints(ppd=%p)", ppd));

 /*
  * Create an array to hold the constraint data...
  */

  ppd->cups_uiconstraints = cupsArrayNew(NULL, NULL);

 /*
  * Find the installable options group if it exists...
  */

  for (i = ppd->num_groups, installable = ppd->groups;
       i > 0;
       i --, installable ++)
    if (!_cups_strcasecmp(installable->name, "InstallableOptions"))
      break;

  if (i <= 0)
    installable = NULL;

 /*
  * Load old-style [Non]UIConstraints data...
  */

  for (i = ppd->num_consts, oldconst = ppd->consts; i > 0; i --, oldconst ++)
  {
   /*
    * Weed out nearby duplicates, since the PPD spec requires that you
    * define both "*Foo foo *Bar bar" and "*Bar bar *Foo foo"...
    */

    if (i > 1 &&
        !_cups_strcasecmp(oldconst[0].option1, oldconst[1].option2) &&
        !_cups_strcasecmp(oldconst[0].choice1, oldconst[1].choice2) &&
        !_cups_strcasecmp(oldconst[0].option2, oldconst[1].option1) &&
        !_cups_strcasecmp(oldconst[0].choice2, oldconst[1].choice1))
      continue;

   /*
    * Allocate memory...
    */

    if ((consts = calloc(1, sizeof(_ppd_cups_uiconsts_t))) == NULL)
    {
      DEBUG_puts("8ppd_load_constraints: Unable to allocate memory for "
                 "UIConstraints!");
      return;
    }

    if ((constptr = calloc(2, sizeof(_ppd_cups_uiconst_t))) == NULL)
    {
      free(consts);
      DEBUG_puts("8ppd_load_constraints: Unable to allocate memory for "
                 "UIConstraints!");
      return;
    }

   /*
    * Fill in the information...
    */

    consts->num_constraints = 2;
    consts->constraints     = constptr;

    if (!_cups_strncasecmp(oldconst->option1, "Custom", 6) &&
        !_cups_strcasecmp(oldconst->choice1, "True"))
    {
      constptr[0].option      = ppdFindOption(ppd, oldconst->option1 + 6);
      constptr[0].choice      = ppdFindChoice(constptr[0].option, "Custom");
      constptr[0].installable = 0;
    }
    else
    {
      constptr[0].option      = ppdFindOption(ppd, oldconst->option1);
      constptr[0].choice      = ppdFindChoice(constptr[0].option,
                                              oldconst->choice1);
      constptr[0].installable = ppd_is_installable(installable,
                                                   oldconst->option1);
    }

    if (!constptr[0].option || (!constptr[0].choice && oldconst->choice1[0]))
    {
      DEBUG_printf(("8ppd_load_constraints: Unknown option *%s %s!",
                    oldconst->option1, oldconst->choice1));
      free(consts->constraints);
      free(consts);
      continue;
    }

    if (!_cups_strncasecmp(oldconst->option2, "Custom", 6) &&
        !_cups_strcasecmp(oldconst->choice2, "True"))
    {
      constptr[1].option      = ppdFindOption(ppd, oldconst->option2 + 6);
      constptr[1].choice      = ppdFindChoice(constptr[1].option, "Custom");
      constptr[1].installable = 0;
    }
    else
    {
      constptr[1].option      = ppdFindOption(ppd, oldconst->option2);
      constptr[1].choice      = ppdFindChoice(constptr[1].option,
                                              oldconst->choice2);
      constptr[1].installable = ppd_is_installable(installable,
                                                   oldconst->option2);
    }

    if (!constptr[1].option || (!constptr[1].choice && oldconst->choice2[0]))
    {
      DEBUG_printf(("8ppd_load_constraints: Unknown option *%s %s!",
                    oldconst->option2, oldconst->choice2));
      free(consts->constraints);
      free(consts);
      continue;
    }

    consts->installable = constptr[0].installable || constptr[1].installable;

   /*
    * Add it to the constraints array...
    */

    cupsArrayAdd(ppd->cups_uiconstraints, consts);
  }

 /*
  * Then load new-style constraints...
  */

  for (constattr = ppdFindAttr(ppd, "cupsUIConstraints", NULL);
       constattr;
       constattr = ppdFindNextAttr(ppd, "cupsUIConstraints", NULL))
  {
    if (!constattr->value)
    {
      DEBUG_puts("8ppd_load_constraints: Bad cupsUIConstraints value!");
      continue;
    }

    for (i = 0, vptr = strchr(constattr->value, '*');
         vptr;
         i ++, vptr = strchr(vptr + 1, '*'));

    if (i == 0)
    {
      DEBUG_puts("8ppd_load_constraints: Bad cupsUIConstraints value!");
      continue;
    }

    if ((consts = calloc(1, sizeof(_ppd_cups_uiconsts_t))) == NULL)
    {
      DEBUG_puts("8ppd_load_constraints: Unable to allocate memory for "
                 "cupsUIConstraints!");
      return;
    }

    if ((constptr = calloc((size_t)i, sizeof(_ppd_cups_uiconst_t))) == NULL)
    {
      free(consts);
      DEBUG_puts("8ppd_load_constraints: Unable to allocate memory for "
                 "cupsUIConstraints!");
      return;
    }

    consts->num_constraints = i;
    consts->constraints     = constptr;

    strlcpy(consts->resolver, constattr->spec, sizeof(consts->resolver));

    for (i = 0, vptr = strchr(constattr->value, '*');
         vptr;
         i ++, vptr = strchr(vptr, '*'), constptr ++)
    {
     /*
      * Extract "*Option Choice" or just "*Option"...
      */

      for (vptr ++, ptr = option; *vptr && !_cups_isspace(*vptr); vptr ++)
        if (ptr < (option + sizeof(option) - 1))
          *ptr++ = *vptr;

      *ptr = '\0';

      while (_cups_isspace(*vptr))
        vptr ++;

      if (*vptr == '*')
        choice[0] = '\0';
      else
      {
        for (ptr = choice; *vptr && !_cups_isspace(*vptr); vptr ++)
          if (ptr < (choice + sizeof(choice) - 1))
            *ptr++ = *vptr;

        *ptr = '\0';
      }

      if (!_cups_strncasecmp(option, "Custom", 6) && !_cups_strcasecmp(choice, "True"))
      {
        _cups_strcpy(option, option + 6);
        strlcpy(choice, "Custom", sizeof(choice));
      }

      constptr->option      = ppdFindOption(ppd, option);
      constptr->choice      = ppdFindChoice(constptr->option, choice);
      constptr->installable = ppd_is_installable(installable, option);
      consts->installable   |= constptr->installable;

      if (!constptr->option || (!constptr->choice && choice[0]))
      {
        DEBUG_printf(("8ppd_load_constraints: Unknown option *%s %s!",
                      option, choice));
        break;
      }
    }

    if (!vptr)
      cupsArrayAdd(ppd->cups_uiconstraints, consts);
    else
    {
      free(consts->constraints);
      free(consts);
    }
  }
}


/*
 * 'ppd_test_constraints()' - See if any constraints are active.
 */

static cups_array_t *                   /* O - Array of active constraints */
ppd_test_constraints(
    ppd_file_t    *ppd,                 /* I - PPD file */
    const char    *option,              /* I - Current option */
    const char    *choice,              /* I - Current choice */
    int           num_options,          /* I - Number of additional options */
    cups_option_t *options,             /* I - Additional options */
    int           which)                /* I - Which constraints to test */
{
  int                   i;              /* Looping var */
  _ppd_cups_uiconsts_t  *consts;        /* Current constraints */
  _ppd_cups_uiconst_t   *constptr;      /* Current constraint */
  ppd_choice_t          key,            /* Search key */
                        *marked;        /* Marked choice */
  cups_array_t          *active = NULL; /* Active constraints */
  const char            *value,         /* Current value */
                        *firstvalue;    /* AP_FIRSTPAGE_Keyword value */
  char                  firstpage[255]; /* AP_FIRSTPAGE_Keyword string */


  DEBUG_printf(("7ppd_test_constraints(ppd=%p, option=\"%s\", choice=\"%s\", "
                "num_options=%d, options=%p, which=%d)", ppd, option, choice,
                num_options, options, which));

  if (!ppd->cups_uiconstraints)
    ppd_load_constraints(ppd);

  DEBUG_printf(("9ppd_test_constraints: %d constraints!",
                cupsArrayCount(ppd->cups_uiconstraints)));

  cupsArraySave(ppd->marked);

  for (consts = (_ppd_cups_uiconsts_t *)cupsArrayFirst(ppd->cups_uiconstraints);
       consts;
       consts = (_ppd_cups_uiconsts_t *)cupsArrayNext(ppd->cups_uiconstraints))
  {
    DEBUG_printf(("9ppd_test_constraints: installable=%d, resolver=\"%s\", "
                  "num_constraints=%d option1=\"%s\", choice1=\"%s\", "
                  "option2=\"%s\", choice2=\"%s\", ...",
                  consts->installable, consts->resolver, consts->num_constraints,
                  consts->constraints[0].option->keyword,
                  consts->constraints[0].choice ?
                      consts->constraints[0].choice->choice : "",
                  consts->constraints[1].option->keyword,
                  consts->constraints[1].choice ?
                      consts->constraints[1].choice->choice : ""));

    if (consts->installable && which < _PPD_INSTALLABLE_CONSTRAINTS)
      continue;                         /* Skip installable option constraint */

    if (!consts->installable && which == _PPD_INSTALLABLE_CONSTRAINTS)
      continue;                         /* Skip non-installable option constraint */

    if ((which == _PPD_OPTION_CONSTRAINTS || which == _PPD_INSTALLABLE_CONSTRAINTS) && option)
    {
     /*
      * Skip constraints that do not involve the current option...
      */

      for (i = consts->num_constraints, constptr = consts->constraints;
           i > 0;
           i --, constptr ++)
      {
        if (!_cups_strcasecmp(constptr->option->keyword, option))
          break;

        if (!_cups_strncasecmp(option, "AP_FIRSTPAGE_", 13) &&
            !_cups_strcasecmp(constptr->option->keyword, option + 13))
          break;
      }

      if (!i)
        continue;
    }

    DEBUG_puts("9ppd_test_constraints: Testing...");

    for (i = consts->num_constraints, constptr = consts->constraints;
         i > 0;
         i --, constptr ++)
    {
      DEBUG_printf(("9ppd_test_constraints: %s=%s?", constptr->option->keyword,
                    constptr->choice ? constptr->choice->choice : ""));

      if (constptr->choice &&
          (!_cups_strcasecmp(constptr->option->keyword, "PageSize") ||
           !_cups_strcasecmp(constptr->option->keyword, "PageRegion")))
      {
       /*
        * PageSize and PageRegion are used depending on the selected input slot
        * and manual feed mode.  Validate against the selected page size instead
        * of an individual option...
        */

        if (option && choice &&
            (!_cups_strcasecmp(option, "PageSize") ||
             !_cups_strcasecmp(option, "PageRegion")))
        {
          value = choice;
        }
        else if ((value = cupsGetOption("PageSize", num_options,
                                        options)) == NULL)
          if ((value = cupsGetOption("PageRegion", num_options,
                                     options)) == NULL)
            if ((value = cupsGetOption("media", num_options, options)) == NULL)
            {
              ppd_size_t *size = ppdPageSize(ppd, NULL);

              if (size)
                value = size->name;
            }

        if (value && !_cups_strncasecmp(value, "Custom.", 7))
          value = "Custom";

        if (option && choice &&
            (!_cups_strcasecmp(option, "AP_FIRSTPAGE_PageSize") ||
             !_cups_strcasecmp(option, "AP_FIRSTPAGE_PageRegion")))
        {
          firstvalue = choice;
        }
        else if ((firstvalue = cupsGetOption("AP_FIRSTPAGE_PageSize",
                                             num_options, options)) == NULL)
          firstvalue = cupsGetOption("AP_FIRSTPAGE_PageRegion", num_options,
                                     options);

        if (firstvalue && !_cups_strncasecmp(firstvalue, "Custom.", 7))
          firstvalue = "Custom";

        if ((!value || _cups_strcasecmp(value, constptr->choice->choice)) &&
            (!firstvalue || _cups_strcasecmp(firstvalue, constptr->choice->choice)))
        {
          DEBUG_puts("9ppd_test_constraints: NO");
          break;
        }
      }
      else if (constptr->choice)
      {
       /*
        * Compare against the constrained choice...
        */

        if (option && choice && !_cups_strcasecmp(option, constptr->option->keyword))
        {
          if (!_cups_strncasecmp(choice, "Custom.", 7))
            value = "Custom";
          else
            value = choice;
        }
        else if ((value = cupsGetOption(constptr->option->keyword, num_options,
                                        options)) != NULL)
        {
          if (!_cups_strncasecmp(value, "Custom.", 7))
            value = "Custom";
        }
        else if (constptr->choice->marked)
          value = constptr->choice->choice;
        else
          value = NULL;

       /*
        * Now check AP_FIRSTPAGE_option...
        */

        snprintf(firstpage, sizeof(firstpage), "AP_FIRSTPAGE_%s",
                 constptr->option->keyword);

        if (option && choice && !_cups_strcasecmp(option, firstpage))
        {
          if (!_cups_strncasecmp(choice, "Custom.", 7))
            firstvalue = "Custom";
          else
            firstvalue = choice;
        }
        else if ((firstvalue = cupsGetOption(firstpage, num_options,
                                             options)) != NULL)
        {
          if (!_cups_strncasecmp(firstvalue, "Custom.", 7))
            firstvalue = "Custom";
        }
        else
          firstvalue = NULL;

        DEBUG_printf(("9ppd_test_constraints: value=%s, firstvalue=%s", value,
                      firstvalue));

        if ((!value || _cups_strcasecmp(value, constptr->choice->choice)) &&
            (!firstvalue || _cups_strcasecmp(firstvalue, constptr->choice->choice)))
        {
          DEBUG_puts("9ppd_test_constraints: NO");
          break;
        }
      }
      else if (option && choice &&
               !_cups_strcasecmp(option, constptr->option->keyword))
      {
        if (!_cups_strcasecmp(choice, "None") || !_cups_strcasecmp(choice, "Off") ||
            !_cups_strcasecmp(choice, "False"))
        {
          DEBUG_puts("9ppd_test_constraints: NO");
          break;
        }
      }
      else if ((value = cupsGetOption(constptr->option->keyword, num_options,
                                      options)) != NULL)
      {
        if (!_cups_strcasecmp(value, "None") || !_cups_strcasecmp(value, "Off") ||
            !_cups_strcasecmp(value, "False"))
        {
          DEBUG_puts("9ppd_test_constraints: NO");
          break;
        }
      }
      else
      {
        key.option = constptr->option;

        if ((marked = (ppd_choice_t *)cupsArrayFind(ppd->marked, &key))
                == NULL ||
            (!_cups_strcasecmp(marked->choice, "None") ||
             !_cups_strcasecmp(marked->choice, "Off") ||
             !_cups_strcasecmp(marked->choice, "False")))
        {
          DEBUG_puts("9ppd_test_constraints: NO");
          break;
        }
      }
    }

    if (i <= 0)
    {
      if (!active)
        active = cupsArrayNew(NULL, NULL);

      cupsArrayAdd(active, consts);
      DEBUG_puts("9ppd_test_constraints: Added...");
    }
  }

  cupsArrayRestore(ppd->marked);

  DEBUG_printf(("8ppd_test_constraints: Found %d active constraints!",
                cupsArrayCount(active)));

  return (active);
}