server/common/object.C

/*
 * static char *rcsid_object_c =
 *   "$Id: object.C,v 1.11 2006-09-03 00:18:40 root Exp $";
 */

/*
    CrossFire, A Multiplayer game for X-windows

    Copyright (C) 2001 Mark Wedel & Crossfire Development Team
    Copyright (C) 1992 Frank Tore Johansen

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

    The authors can be reached via e-mail at crossfire-devel@real-time.com
*/

/* Eneq(@csd.uu.se): Added weight-modifiers in environment of objects.
   sub/add_weight will transcend the environment updating the carrying
   variable. */
#include <global.h>
#ifndef WIN32 /* ---win32 exclude headers */
#include <stdio.h>
#include <sys/types.h>
#include <sys/uio.h>
#endif /* win32 */
#include <object.h>
#include <funcpoint.h>
#include <skills.h>
#include <loader.h>
#ifdef MEMORY_DEBUG
int nroffreeobjects = 0;
int nrofallocobjects = 0;
#undef OBJ_EXPAND
#define OBJ_EXPAND 1
#else
object objarray[STARTMAX]; /* All objects, allocated this way at first */
int nroffreeobjects = STARTMAX;  /* How many OBs allocated and free (free) */
int nrofallocobjects = STARTMAX; /* How many OBs allocated (free + used) */
#endif

object *objects;           /* Pointer to the list of used objects */
object *free_objects;      /* Pointer to the list of unused objects */
object *active_objects; /* List of active objects that need to be processed */

short freearr_x[SIZEOFFREE]=
  {0,0,1,1,1,0,-1,-1,-1,0,1,2,2,2,2,2,1,0,-1,-2,-2,-2,-2,-2,-1,
   0,1,2,3,3,3,3,3,3,3,2,1,0,-1,-2,-3,-3,-3,-3,-3,-3,-3,-2,-1};
short freearr_y[SIZEOFFREE]=
  {0,-1,-1,0,1,1,1,0,-1,-2,-2,-2,-1,0,1,2,2,2,2,2,1,0,-1,-2,-2,
   -3,-3,-3,-3,-2,-1,0,1,2,3,3,3,3,3,3,3,2,1,0,-1,-2,-3,-3,-3};
int maxfree[SIZEOFFREE]=
  {0,9,10,13,14,17,18,21,22,25,26,27,30,31,32,33,36,37,39,39,42,43,44,45,
  48,49,49,49,49,49,49,49,49,49,49,49,49,49,49,49,49,49,49,49,49,49,49,49,49};
int freedir[SIZEOFFREE]= {
  0,1,2,3,4,5,6,7,8,1,2,2,2,3,4,4,4,5,6,6,6,7,8,8,8,
  1,2,2,2,2,2,3,4,4,4,4,4,5,6,6,6,6,6,7,8,8,8,8,8};


/* Returns TRUE if every key_values in wants has a partner with the same value in has. */
static int compare_ob_value_lists_one(const object * wants, const object * has) {
    key_value * wants_field;
    
    /* n-squared behaviour (see get_ob_key_link()), but I'm hoping both
     * objects with lists are rare, and lists stay short. If not, use a
     * different structure or at least keep the lists sorted... 
     */
    
    /* For each field in wants, */
    for (wants_field = wants->key_values; wants_field != NULL; wants_field = wants_field->next) {
        key_value * has_field;
        
        /* Look for a field in has with the same key. */
        has_field = get_ob_key_link(has, wants_field->key);
        
        if (has_field == NULL) {
            /* No field with that name. */
            return FALSE;
        }
        
        /* Found the matching field. */
        if (has_field->value != wants_field->value) {
            /* Values don't match, so this half of the comparison is false. */
            return FALSE;
        } 
        
        /* If we get here, we found a match. Now for the next field in wants. */
    }
    
    /* If we get here, every field in wants has a matching field in has. */
    return TRUE;
}

/* Returns TRUE if ob1 has the same key_values as ob2. */
static int compare_ob_value_lists(const object * ob1, const object * ob2) {
    /* However, there may be fields in has which aren't partnered in wants,
     * so we need to run the comparison *twice*. :(
     */
    return compare_ob_value_lists_one(ob1, ob2) && compare_ob_value_lists_one(ob2, ob1);
}

/* Function examines the 2 objects given to it, and returns true if
 * they can be merged together.
 *
 * Note that this function appears a lot longer than the macro it
 * replaces - this is mostly for clarity - a decent compiler should hopefully
 * reduce this to the same efficiency.
 *
 * Check nrof variable *before* calling CAN_MERGE()
 *
 * Improvements made with merge:  Better checking on potion, and also
 * check weight
 */

int CAN_MERGE(object *ob1, object *ob2) {

    /* A couple quicksanity checks */
    if ((ob1 == ob2) || (ob1->type != ob2->type)) return 0;

    if (ob1->speed != ob2->speed) return 0;
    /* Note sure why the following is the case - either the object has to
     * be animated or have a very low speed.  Is this an attempted monster
     * check?
     */
    if (!QUERY_FLAG(ob1,FLAG_ANIMATE) && FABS((ob1)->speed) > MIN_ACTIVE_SPEED)
        return 0;

    /* Do not merge objects if nrof would overflow. We use 1UL<<31 since that
     * value could not be stored in a sint32 (which unfortunately sometimes is
     * used to store nrof).
     */
    if (ob1->nrof+ob2->nrof >= 1UL<<31)
        return 0;

    /* This is really a spellbook check - really, we should
     * check all objects in the inventory.
     */
    if (ob1->inv || ob2->inv) {
        /* if one object has inventory but the other doesn't, not equiv */
        if ((ob1->inv && !ob2->inv) || (ob2->inv && !ob1->inv)) return 0;

        /* Now check to see if the two inventory objects could merge */
        if (!CAN_MERGE(ob1->inv, ob2->inv)) return 0;

        /* inventory ok - still need to check rest of this object to see
         * if it is valid.
         */
    }

    /* If the objects have been identified, set the BEEN_APPLIED flag.
     * This is to the comparison of the flags below will be OK.  We
     * just can't ignore the been applied or identified flags, as they
     * are not equal - just if it has been identified, the been_applied
     * flags lose any meaning.
     */
    if (QUERY_FLAG(ob1, FLAG_IDENTIFIED))
        SET_FLAG(ob1, FLAG_BEEN_APPLIED);

    if (QUERY_FLAG(ob2, FLAG_IDENTIFIED))
        SET_FLAG(ob2, FLAG_BEEN_APPLIED);


    /* the 0x400000 on flags2 is FLAG_INV_LOCK.  I don't think something
     * being locked in inventory should prevent merging.
     * 0x4 in flags3 is CLIENT_SENT
     */
    if ((ob1->arch != ob2->arch) || 
        (ob1->flags[0] != ob2->flags[0]) || 
        (ob1->flags[1] != ob2->flags[1]) ||
        ((ob1->flags[2] & ~0x400000) != (ob2->flags[2] & ~ 0x400000)) ||
        ((ob1->flags[3] & ~0x4) != (ob2->flags[3] & ~0x4)) || 
        (ob1->name != ob2->name) || 
        (ob1->title != ob2->title) ||
        (ob1->msg != ob2->msg) || 
        (ob1->weight != ob2->weight) ||
        (memcmp(&ob1->resist, &ob2->resist, sizeof(ob1->resist))!=0) ||
        (memcmp(&ob1->stats, &ob2->stats, sizeof(ob1->stats))!=0) ||
        (ob1->attacktype != ob2->attacktype) ||
        (ob1->magic != ob2->magic) ||
        (ob1->slaying != ob2->slaying) ||
        (ob1->skill != ob2->skill) ||
        (ob1->value != ob2->value) ||
        (ob1->animation_id != ob2->animation_id) ||
        (ob1->client_type != ob2->client_type) ||
        (ob1->materialname != ob2->materialname) ||
        (ob1->lore != ob2->lore) ||
        (ob1->subtype != ob2->subtype) ||
        (ob1->move_type != ob2->move_type) ||
        (ob1->move_block != ob2->move_block) ||
        (ob1->move_allow != ob2->move_allow) ||
        (ob1->move_on != ob2->move_on) ||
        (ob1->move_off != ob2->move_off) ||
        (ob1->move_slow != ob2->move_slow) ||
        (ob1->move_slow_penalty != ob2->move_slow_penalty) 
        ) 
            return 0;

    /* Don't merge objects that are applied.  With the new 'body' code,
     * it is possible for most any character to have more than one of
     * some items equipped, and we don't want those to merge.
     */
    if (QUERY_FLAG(ob1, FLAG_APPLIED) || QUERY_FLAG(ob2, FLAG_APPLIED))
        return 0;

    switch (ob1->type) {
        case SCROLL:
            if (ob1->level != ob2->level) return 0;
            break;

    }
    if (ob1->key_values != NULL || ob2->key_values != NULL) {
        /* At least one of these has key_values. */
        if ((ob1->key_values == NULL) != (ob2->key_values == NULL)) {
            /* One has fields, but the other one doesn't. */
            return 0;
        } else if (!compare_ob_value_lists(ob1, ob2)) {
            return 0;
        }
    }

    /* Everything passes, must be OK. */
    return 1;
}

/*
 * sum_weight() is a recursive function which calculates the weight
 * an object is carrying.  It goes through in figures out how much
 * containers are carrying, and sums it up.
 */
signed long sum_weight(object *op) {
  signed long sum;
  object *inv;
  for(sum = 0, inv = op->inv; inv != NULL; inv = inv->below) {
    if (inv->inv)
        sum_weight(inv);
    sum += inv->carrying + inv->weight * (inv->nrof ? inv->nrof : 1);
  }
  if (op->type == CONTAINER && op->stats.Str)
    sum = (sum * (100 - op->stats.Str))/100;
  if(op->carrying != sum)
    op->carrying = sum;
  return sum;
}

/**
 * Return the outermost environment object for a given object.
 */

object *object_get_env_recursive (object *op) {
    while (op->env != NULL)
        op = op->env;
    return op;
}

/*
 * Eneq(@csd.uu.se): Since we can have items buried in a character we need
 * a better check.  We basically keeping traversing up until we can't
 * or find a player.
 */

object *is_player_inv (object *op) { 
    for (;op!=NULL&&op->type!=PLAYER; op=op->env)
      if (op->env==op)
        op->env = NULL;
    return op;
}

/*
 * Used by: Crossedit: dump. Server DM commands: dumpbelow, dump.
 *      Some error messages.
 * The result of the dump is stored in the static global errmsg array.
 */

void dump_object2(object *op) {
errmsg[0] = 0;
return;
  //TODO//D#d#
#if 0
  char *cp;
/*  object *tmp;*/

  if(op->arch!=NULL) {
      strcat(errmsg,"arch ");
      strcat(errmsg,op->arch->name?op->arch->name:"(null)");
      strcat(errmsg,"\n");
      if((cp=get_ob_diff(op,&empty_archetype->clone))!=NULL)
        strcat(errmsg,cp);
#if 0
      /* Don't dump player diffs - they are too long, mostly meaningless, and
       * will overflow the buffer.
       * Changed so that we don't dump inventory either.  This may
       * also overflow the buffer.
       */
      if(op->type!=PLAYER && (cp=get_ob_diff(op,&empty_archetype->clone))!=NULL)
        strcat(errmsg,cp);
      for (tmp=op->inv; tmp; tmp=tmp->below)
        dump_object2(tmp);
#endif
      strcat(errmsg,"end\n");
  } else {
      strcat(errmsg,"Object ");
      if (op->name==NULL) strcat(errmsg, "(null)");
      else strcat(errmsg,op->name);
      strcat(errmsg,"\n");
#if 0
      if((cp=get_ob_diff(op,&empty_archetype->clone))!=NULL)
        strcat(errmsg,cp);
      for (tmp=op->inv; tmp; tmp=tmp->below)
        dump_object2(tmp);
#endif
      strcat(errmsg,"end\n");
  }
#endif
}

/*
 * Dumps an object.  Returns output in the static global errmsg array.
 */

void dump_object(object *op) {
  if(op==NULL) {
    strcpy(errmsg,"[NULL pointer]");
    return;
  }
  errmsg[0]='\0';
  dump_object2(op);
}

void dump_all_objects(void) {
  object *op;
  for(op=objects;op!=NULL;op=op->next) {
    dump_object(op);
    fprintf(logfile, "Object %d\n:%s\n", op->count, errmsg);
  }
}

/*
 * get_nearest_part(multi-object, object 2) returns the part of the
 * multi-object 1 which is closest to the second object.
 * If it's not a multi-object, it is returned.
 */

object *get_nearest_part(object *op, const object *pl) {
  object *tmp,*closest;
  int last_dist,i;
  if(op->more==NULL)
    return op;
  for(last_dist=distance(op,pl),closest=op,tmp=op->more;tmp!=NULL;tmp=tmp->more)
    if((i=distance(tmp,pl))<last_dist)
      closest=tmp,last_dist=i;
  return closest;
}

/*
 * Returns the object which has the count-variable equal to the argument.
 */

object *find_object(tag_t i) {
  object *op;
  for(op=objects;op!=NULL;op=op->next)
    if(op->count==i)
      break;
 return op;
}

/*
 * Returns the first object which has a name equal to the argument.
 * Used only by the patch command, but not all that useful.
 * Enables features like "patch <name-of-other-player> food 999"
 */

object *find_object_name(const char *str) {
  const char *name = shstr::find (str);
  object *op;
  for(op=objects;op!=NULL;op=op->next)
    if(&op->name == name)
      break;

  return op;
}

void free_all_object_data(void) {
#ifdef MEMORY_DEBUG
    object *op, *next;

    for (op=free_objects; op!=NULL; ) {
        next=op->next;
        free(op);
        nrofallocobjects--;
        nroffreeobjects--;
        op=next;
    }
#endif
    LOG(llevDebug,"%d allocated objects, %d free objects, STARMAX=%d\n", 
        nrofallocobjects, nroffreeobjects,STARTMAX);
}

/*
 * Returns the object which this object marks as being the owner.
 * A id-scheme is used to avoid pointing to objects which have been
 * freed and are now reused.  If this is detected, the owner is
 * set to NULL, and NULL is returned.
 * Changed 2004-02-12 - if the player is setting at the play again
 * prompt, he is removed, and we don't want to treat him as an owner of
 * anything, so check removed flag.  I don't expect that this should break
 * anything - once an object is removed, it is basically dead anyways.
 */

object *get_owner(object *op) {
    if(op->owner==NULL)
        return NULL;

    if (!QUERY_FLAG(op->owner,FLAG_FREED) && !QUERY_FLAG(op->owner, FLAG_REMOVED) &&
        op->owner->count==op->ownercount)
        return op->owner;

    op->owner=NULL;
    op->ownercount=0;
    return NULL;
}

void clear_owner(object *op)
{
    if (!op) return;

    if (op->owner && op->ownercount == op->owner->count)
        op->owner->refcount--;

    op->owner = NULL;
    op->ownercount = 0;
}


/*
 * Sets the owner and sets the skill and exp pointers to owner's current
 * skill and experience objects.
 */
void set_owner (object *op, object *owner)
{
    if(owner==NULL||op==NULL)
        return;

    /* next line added to allow objects which own objects */ 
    /* Add a check for ownercounts in here, as I got into an endless loop
     * with the fireball owning a poison cloud which then owned the
     * fireball.  I believe that was caused by one of the objects getting
     * freed and then another object replacing it.  Since the ownercounts
     * didn't match, this check is valid and I believe that cause is valid.
     */
    while (owner->owner && owner!=owner->owner && 
        owner->ownercount==owner->owner->count) owner=owner->owner;

    /* IF the owner still has an owner, we did not resolve to a final owner.
     * so lets not add to that.
     */
    if (owner->owner) return;

    op->owner=owner;

    op->ownercount=owner->count;
    owner->refcount++;

}

/* Set the owner to clone's current owner and set the skill and experience
 * objects to clone's objects (typically those objects that where the owner's
 * current skill and experience objects at the time when clone's owner was
 * set - not the owner's current skill and experience objects).
 *
 * Use this function if player created an object (e.g. fire bullet, swarm
 * spell), and this object creates further objects whose kills should be
 * accounted for the player's original skill, even if player has changed
 * skills meanwhile.
 */
void copy_owner (object *op, object *clone)
{
    object *owner = get_owner (clone);
    if (owner == NULL) {
        /* players don't have owners - they own themselves.  Update
         * as appropriate.
         */
        if (clone->type == PLAYER) owner=clone;
        else return;
    }
    set_owner(op, owner);

}

/*
 * Resets vital variables in an object
 */

void reset_object(object *op) {

    op->name = NULL;
    op->name_pl = NULL;
    op->title = NULL;
    op->race = NULL;
    op->slaying = NULL;
    op->skill = NULL;
    op->msg = NULL;
    op->materialname = NULL;
    op->lore = NULL;
    clear_object(op);
}

/* Zero the key_values on op, decrementing the shared-string
 * refcounts and freeing the links. 
 */
static void free_key_values(object * op)
{
  for (key_value *i = op->key_values; i != 0; )
    {
      key_value *next = i->next;
      delete i;
      i = next;
    }
  
  op->key_values = 0;
}

/*
 * clear_object() frees everything allocated by an object, and also
 * clears all variables and flags to default settings.
 */

void clear_object(object *op)
{
  op->clear ();

  free_key_values (op);

  /* the memset will clear all these values for us, but we need
   * to reduce the refcount on them.
   */
  op->name         = 0;
  op->name_pl      = 0;
  op->title        = 0;
  op->race         = 0;
  op->slaying      = 0;
  op->skill        = 0;
  op->msg          = 0;
  op->lore         = 0;
  op->materialname = 0;

  memset((void*)op, 0, sizeof (object_special));
  /* Below here, we clear things that are not done by the memset,
   * or set default values that are not zero.
   */
  /* This is more or less true */
  SET_FLAG (op, FLAG_REMOVED);

  op->contr = NULL;
  op->below = NULL;
  op->above = NULL;
  op->inv   = NULL;
  op->container=NULL;
  op->env=NULL;
  op->more=NULL;
  op->head=NULL;
  op->map=NULL;
  op->refcount=0;
  op->active_next = NULL;
  op->active_prev = NULL;
  /* What is not cleared is next, prev, and count */

  op->expmul=1.0;
  op->face = blank_face;
  op->attacked_by_count = (tag_t) -1;

  if (settings.casting_time)
    op->casting_time = -1;
}

/*
 * copy object first frees everything allocated by the second object,
 * and then copies the contends of the first object into the second
 * object, allocating what needs to be allocated.  Basically, any
 * data that is malloc'd needs to be re-malloc/copied.  Otherwise,
 * if the first object is freed, the pointers in the new object
 * will point at garbage.
 */

void copy_object(object *op2, object *op)
{
  int is_freed=QUERY_FLAG(op,FLAG_FREED),is_removed=QUERY_FLAG(op,FLAG_REMOVED);

  op->clear ();

  free_key_values (op);

  *(object_special *)op = *(object_special *)op2;
  op2->clone (op);

  if (is_freed)            SET_FLAG(op,FLAG_FREED);
  if (is_removed)          SET_FLAG(op,FLAG_REMOVED);

  if (op2->speed < 0)
    op->speed_left = op2->speed_left - RANDOM() % 200 / 100.0;

  /* Copy over key_values, if any. */
  if (op2->key_values != NULL) {
      key_value *tail = NULL;
      key_value *i;

      op->key_values = NULL;

      for (i = op2->key_values; i != NULL; i = i->next)
        {
          key_value *new_link = new key_value;

          new_link->next  = NULL;
          new_link->key   = i->key;
          new_link->value = i->value;

          /* Try and be clever here, too. */
          if (op->key_values == NULL)
            {
              op->key_values = new_link;
              tail = new_link;
            }
          else
            {
              tail->next = new_link;
              tail = new_link;
            }
      }
  }

  update_ob_speed (op);
}

/*
 * expand_objects() allocates more objects for the list of unused objects.
 * It is called from get_object() if the unused list is empty.
 */

void expand_objects(void) {
  int i;
  object *obj;
  obj = new object [OBJ_EXPAND];

  free_objects=obj;
  obj[0].prev=NULL;
  obj[0].next= &obj[1],
  SET_FLAG(&(obj[0]), FLAG_REMOVED);
  SET_FLAG(&(obj[0]), FLAG_FREED);

  for(i=1;i<OBJ_EXPAND-1;i++) {
    obj[i].next= &obj[i+1],
    obj[i].prev= &obj[i-1],
    SET_FLAG(&(obj[i]), FLAG_REMOVED);
    SET_FLAG(&(obj[i]), FLAG_FREED);
  }
  obj[OBJ_EXPAND-1].prev= &obj[OBJ_EXPAND-2],
  obj[OBJ_EXPAND-1].next=NULL,
  SET_FLAG(&(obj[OBJ_EXPAND-1]), FLAG_REMOVED);
  SET_FLAG(&(obj[OBJ_EXPAND-1]), FLAG_FREED);

  nrofallocobjects += OBJ_EXPAND;
  nroffreeobjects += OBJ_EXPAND;
}

/*
 * get_object() grabs an object from the list of unused objects, makes
 * sure it is initialised, and returns it.
 * If there are no free objects, expand_objects() is called to get more.
 */

object *get_object(void)
{
  object *op;

  if(free_objects==NULL)
    expand_objects();

  op = free_objects;

  if (!QUERY_FLAG (op, FLAG_FREED))
    LOG(llevError,"Fatal: Getting busy object.\n");

  free_objects = op->next;

  if (free_objects != NULL)
    free_objects->prev = NULL;

  op->count= ++ob_count;
  op->name=NULL;
  op->name_pl=NULL;
  op->title=NULL;
  op->race=NULL;
  op->slaying=NULL;
  op->skill = NULL;
  op->lore=NULL;
  op->msg=NULL;
  op->materialname=NULL;
  op->next=objects;
  op->prev=NULL;
  op->active_next = NULL;
  op->active_prev = NULL;
  if(objects!=NULL)
    objects->prev=op;
  objects=op;
  clear_object(op);
  SET_FLAG(op,FLAG_REMOVED);
  nroffreeobjects--;
  return op;
}

/*
 * If an object with the IS_TURNABLE() flag needs to be turned due
 * to the closest player being on the other side, this function can
 * be called to update the face variable, _and_ how it looks on the map.
 */

void update_turn_face(object *op) {
    if(!QUERY_FLAG(op,FLAG_IS_TURNABLE)||op->arch==NULL)
        return;
    SET_ANIMATION(op, op->direction);
    update_object(op,UP_OBJ_FACE);
}

/*
 * Updates the speed of an object.  If the speed changes from 0 to another
 * value, or vice versa, then add/remove the object from the active list.
 * This function needs to be called whenever the speed of an object changes.
 */

void update_ob_speed(object *op) {
    extern int arch_init;

    /* No reason putting the archetypes objects on the speed list,
     * since they never really need to be updated.
     */

    if (QUERY_FLAG(op, FLAG_FREED) && op->speed) {
        LOG(llevError,"Object %s is freed but has speed.\n", &op->name);
#ifdef MANY_CORES
        abort();
#else
        op->speed = 0;
#endif
    }
    if (arch_init) {
        return;
    }
    if (FABS(op->speed)>MIN_ACTIVE_SPEED) {
        /* If already on active list, don't do anything */
        if (op->active_next || op->active_prev || op==active_objects)
            return;

        /* process_events() expects us to insert the object at the beginning
         * of the list. */
        op->active_next = active_objects;
        if (op->active_next!=NULL)
                op->active_next->active_prev = op;
        active_objects = op;
    }
    else {
        /* If not on the active list, nothing needs to be done */
        if (!op->active_next && !op->active_prev && op!=active_objects)
            return;

        if (op->active_prev==NULL) {
            active_objects = op->active_next;
            if (op->active_next!=NULL)
                op->active_next->active_prev = NULL;
        }
        else {
            op->active_prev->active_next = op->active_next;
            if (op->active_next)
                op->active_next->active_prev = op->active_prev;
        }
        op->active_next = NULL;
        op->active_prev = NULL;
    }
}

/* This function removes object 'op' from the list of active
 * objects.
 * This should only be used for style maps or other such 
 * reference maps where you don't want an object that isn't
 * in play chewing up cpu time getting processed.
 * The reverse of this is to call update_ob_speed, which
 * will do the right thing based on the speed of the object.
 */
void remove_from_active_list(object *op)
{
    /* If not on the active list, nothing needs to be done */
    if (!op->active_next && !op->active_prev && op!=active_objects)
        return;

    if (op->active_prev==NULL) {
        active_objects = op->active_next;
        if (op->active_next!=NULL)
            op->active_next->active_prev = NULL;
    }
    else {
        op->active_prev->active_next = op->active_next;
        if (op->active_next)
            op->active_next->active_prev = op->active_prev;
    }
    op->active_next = NULL;
    op->active_prev = NULL;
}

/*
 * update_object() updates the array which represents the map.
 * It takes into account invisible objects (and represent squares covered
 * by invisible objects by whatever is below them (unless it's another
 * invisible object, etc...)
 * If the object being updated is beneath a player, the look-window
 * of that player is updated (this might be a suboptimal way of
 * updating that window, though, since update_object() is called _often_)
 *
 * action is a hint of what the caller believes need to be done.
 * For example, if the only thing that has changed is the face (due to
 * an animation), we don't need to call update_position until that actually
 * comes into view of a player.  OTOH, many other things, like addition/removal
 * of walls or living creatures may need us to update the flags now.
 * current action are:
 * UP_OBJ_INSERT: op was inserted
 * UP_OBJ_REMOVE: op was removed
 * UP_OBJ_CHANGE: object has somehow changed.  In this case, we always update
 *  as that is easier than trying to look at what may have changed.
 * UP_OBJ_FACE: only the objects face has changed.
 */

void update_object(object *op, int action) {
    int update_now=0, flags;
    MoveType    move_on, move_off, move_block, move_slow;
    
    if (op == NULL) {
        /* this should never happen */
        LOG(llevDebug,"update_object() called for NULL object.\n");
        return;
    }
    
    if(op->env!=NULL) {
        /* Animation is currently handled by client, so nothing
         * to do in this case.
         */
        return;
    }

    /* If the map is saving, don't do anything as everything is
     * going to get freed anyways.
     */
    if (!op->map || op->map->in_memory == MAP_SAVING) return;
    
    /* make sure the object is within map boundaries */
    if (op->x < 0 || op->x >= MAP_WIDTH(op->map) ||
        op->y < 0 || op->y >= MAP_HEIGHT(op->map)) {
        LOG(llevError,"update_object() called for object out of map!\n");
#ifdef MANY_CORES
        abort();
#endif
        return;
    }
    
    flags = GET_MAP_FLAGS(op->map, op->x, op->y);
    SET_MAP_FLAGS(op->map, op->x, op->y, flags | P_NEED_UPDATE);
    move_slow = GET_MAP_MOVE_SLOW(op->map, op->x, op->y);
    move_on = GET_MAP_MOVE_ON(op->map, op->x, op->y);
    move_block = GET_MAP_MOVE_BLOCK(op->map, op->x, op->y);
    move_off = GET_MAP_MOVE_OFF(op->map, op->x, op->y);

    if (action == UP_OBJ_INSERT) {
        if (QUERY_FLAG(op, FLAG_BLOCKSVIEW) && !(flags & P_BLOCKSVIEW))
            update_now=1;

        if (QUERY_FLAG(op, FLAG_NO_MAGIC) && !(flags & P_NO_MAGIC))
            update_now=1;

        if (QUERY_FLAG(op, FLAG_DAMNED) && !(flags & P_NO_CLERIC))
            update_now=1;

        if (QUERY_FLAG(op, FLAG_ALIVE) && !(flags & P_IS_ALIVE))
            update_now=1;

        if ((move_on | op->move_on) != move_on) update_now=1;
        if ((move_off | op->move_off) != move_off) update_now=1;
        /* This isn't perfect, but I don't expect a lot of objects to
         * to have move_allow right now.    
         */
        if (((move_block | op->move_block) & ~op->move_allow) != move_block) 
            update_now=1;
        if ((move_slow | op->move_slow) != move_slow) update_now=1;
    } 
    /* if the object is being removed, we can't make intelligent
     * decisions, because remove_ob can't really pass the object
     * that is being removed.
     */
    else if (action == UP_OBJ_CHANGE || action == UP_OBJ_REMOVE) {
        update_now=1;
    } else if (action == UP_OBJ_FACE) {
        /* Nothing to do for that case */
    }
    else {
        LOG(llevError,"update_object called with invalid action: %d\n", action);
    }

    if (update_now) {
        SET_MAP_FLAGS(op->map, op->x, op->y, flags | P_NO_ERROR | P_NEED_UPDATE);
        update_position(op->map, op->x, op->y);
    }

    if(op->more!=NULL)
        update_object(op->more, action);
}


/*
 * free_object() frees everything allocated by an object, removes
 * it from the list of used objects, and puts it on the list of
 * free objects.  The IS_FREED() flag is set in the object.
 * The object must have been removed by remove_ob() first for
 * this function to succeed.
 *
 * If free_inventory is set, free inventory as well. Else drop items in
 * inventory to the ground.
 */

void free_object(object *ob) {
    free_object2(ob, 0);
}
void free_object2(object *ob, int free_inventory) {
    object *tmp,*op;

    ob->clear ();

    if (!QUERY_FLAG(ob,FLAG_REMOVED)) {
        LOG(llevDebug,"Free object called with non removed object\n");
        dump_object(ob);
#ifdef MANY_CORES
        abort();
#endif
    }
    if(QUERY_FLAG(ob,FLAG_FRIENDLY)) {
        LOG(llevMonster,"Warning: tried to free friendly object.\n");
        remove_friendly_object(ob);
    }
    if(QUERY_FLAG(ob,FLAG_FREED)) {
        dump_object(ob);
        LOG(llevError,"Trying to free freed object.\n%s\n",errmsg);
        return;
    }
    if(ob->more!=NULL) {
        free_object2(ob->more, free_inventory);
        ob->more=NULL;
    }
    if (ob->inv) {
        /* Only if the space blocks everything do we not process -
         * if some form of movemnt is allowed, let objects
         * drop on that space.
         */
        if (free_inventory || ob->map==NULL || ob->map->in_memory!=MAP_IN_MEMORY ||
            (GET_MAP_MOVE_BLOCK(ob->map, ob->x, ob->y) == MOVE_ALL)) 
        {
            op=ob->inv;
            while(op!=NULL) {
                tmp=op->below;
                remove_ob(op);
                free_object2(op, free_inventory);
                op=tmp;
            }
        }
        else {  /* Put objects in inventory onto this space */
            op=ob->inv;
            while(op!=NULL) {
                tmp=op->below;
                remove_ob(op);
                if(QUERY_FLAG(op,FLAG_STARTEQUIP)||QUERY_FLAG(op,FLAG_NO_DROP) ||
                   op->type==RUNE || op->type==TRAP || QUERY_FLAG(op,FLAG_IS_A_TEMPLATE))
                free_object(op);
                else {
                    op->x=ob->x;
                    op->y=ob->y;
                    insert_ob_in_map(op,ob->map,NULL,0); /* Insert in same map as the envir */
                }
                op=tmp;
            }
        }
    }
    /* Remove object from the active list */
    ob->speed = 0;
    update_ob_speed(ob);

    SET_FLAG(ob, FLAG_FREED);
    ob->count = 0;

    /* Remove this object from the list of used objects */
    if(ob->prev==NULL) {
        objects=ob->next;
        if(objects!=NULL)
            objects->prev=NULL;
    }
    else {
        ob->prev->next=ob->next;
        if(ob->next!=NULL)
            ob->next->prev=ob->prev;
    }
  
    ob->name         = 0;
    ob->name_pl      = 0;
    ob->title        = 0;
    ob->race         = 0;
    ob->slaying      = 0;
    ob->skill        = 0;
    ob->lore         = 0;
    ob->msg          = 0;
    ob->materialname = 0;

    free_key_values (ob);

    /* Now link it with the free_objects list: */
    ob->prev=NULL;
    ob->next=free_objects;

    if(free_objects!=NULL)
        free_objects->prev=ob;

    free_objects=ob;
    nroffreeobjects++;
}

/*
 * count_free() returns the number of objects on the list of free objects.
 */

int count_free ()
{
  int i=0;
  object *tmp=free_objects;
  while(tmp!=NULL)
    tmp=tmp->next, i++;
  return i;
}

/*
 * count_used() returns the number of objects on the list of used objects.
 */

int count_used()
{
  int i=0;
  object *tmp=objects;
  while(tmp!=NULL)
    tmp=tmp->next, i++;
  return i;
}

/*
 * count_active() returns the number of objects on the list of active objects.
 */

int count_active()
{
  int i=0;
  object *tmp=active_objects;
  while(tmp!=NULL)
    tmp=tmp->active_next, i++;
  return i;
}

/*
 * sub_weight() recursively (outwards) subtracts a number from the
 * weight of an object (and what is carried by it's environment(s)).
 */

void sub_weight (object *op, signed long weight) {
  while (op != NULL) {
    if (op->type == CONTAINER) {
      weight=(signed long)(weight*(100-op->stats.Str)/100);
    }
    op->carrying-=weight;
    op = op->env;
  }
}

/* remove_ob(op):
 *   This function removes the object op from the linked list of objects
 *   which it is currently tied to.  When this function is done, the
 *   object will have no environment.  If the object previously had an
 *   environment, the x and y coordinates will be updated to
 *   the previous environment.
 *   Beware: This function is called from the editor as well!
 */

void remove_ob(object *op) {
    object *tmp,*last=NULL;
    object *otmp;
    tag_t tag;
    int check_walk_off;
    mapstruct *m;
    sint16 x,y;
    

    if(QUERY_FLAG(op,FLAG_REMOVED)) {
        dump_object(op);
        LOG(llevError,"Trying to remove removed object.\n%s\n",errmsg);

        /* Changed it to always dump core in this case.  As has been learned
         * in the past, trying to recover from errors almost always
         * make things worse, and this is a real error here - something
         * that should not happen.
         * Yes, if this was a mission critical app, trying to do something
         * to recover may make sense, but that is because failure of the app    
         * may have other disastrous problems.  Cf runs out of a script
         * so is easily enough restarted without any real problems.
         * MSW 2001-07-01
         */
        abort();
    }
    if(op->more!=NULL)
        remove_ob(op->more);

    SET_FLAG(op, FLAG_REMOVED);

    /* 
     * In this case, the object to be removed is in someones
     * inventory.
     */
    if(op->env!=NULL) {
        if(op->nrof)
            sub_weight(op->env, op->weight*op->nrof);
        else
            sub_weight(op->env, op->weight+op->carrying);

        /* NO_FIX_PLAYER is set when a great many changes are being
         * made to players inventory.  If set, avoiding the call
         * to save cpu time.
         */
        if ((otmp=is_player_inv(op->env))!=NULL && otmp->contr && 
            !QUERY_FLAG(otmp,FLAG_NO_FIX_PLAYER))
            fix_player(otmp);

        if(op->above!=NULL)
            op->above->below=op->below;
        else
            op->env->inv=op->below;

        if(op->below!=NULL)
            op->below->above=op->above;

        /* we set up values so that it could be inserted into
         * the map, but we don't actually do that - it is up
         * to the caller to decide what we want to do.
         */
        op->x=op->env->x,op->y=op->env->y;
        op->map=op->env->map;
        op->above=NULL,op->below=NULL;
        op->env=NULL;
        return;
    }

    /* If we get here, we are removing it from a map */
    if (op->map == NULL) return;

    x = op->x;
    y = op->y;
    m = get_map_from_coord(op->map, &x, &y);

    if (!m) {
        LOG(llevError,"remove_ob called when object was on map but appears to not be within valid coordinates? %s (%d,%d)\n",
            op->map->path, op->x, op->y);
        /* in old days, we used to set x and y to 0 and continue.
         * it seems if we get into this case, something is probablye
         * screwed up and should be fixed.
         */
        abort();
    }
    if (op->map != m) {
        LOG(llevDebug,"remove_ob: Object not really on map it claimed to be on? %s != %s, %d,%d != %d,%d\n",
            op->map->path, m->path, op->x, op->y, x, y);
    }

    /* Re did the following section of code - it looks like it had
     * lots of logic for things we no longer care about
     */

    /* link the object above us */
    if (op->above)
        op->above->below=op->below;
    else
        SET_MAP_TOP(m,x,y,op->below); /* we were top, set new top */
    
    /* Relink the object below us, if there is one */
    if(op->below) {
        op->below->above=op->above;
    } else {
        /* Nothing below, which means we need to relink map object for this space 
         * use translated coordinates in case some oddness with map tiling is
         * evident
         */
        if(GET_MAP_OB(m,x,y)!=op) {
            dump_object(op);
            LOG(llevError,"remove_ob: GET_MAP_OB does not return object to be removed even though it appears to be on the bottom?\n%s\n", errmsg);
            dump_object(GET_MAP_OB(m,x,y));
            LOG(llevError,"%s\n",errmsg);
        }
        SET_MAP_OB(m,x,y,op->above);  /* goes on above it. */
    }
    op->above=NULL;                      
    op->below=NULL;

    if (op->map->in_memory == MAP_SAVING)
        return;

    tag = op->count;
    check_walk_off = ! QUERY_FLAG (op, FLAG_NO_APPLY);
    for(tmp=GET_MAP_OB(m,x,y);tmp!=NULL;tmp=tmp->above) {
        /* No point updating the players look faces if he is the object
         * being removed.
         */

        if(tmp->type==PLAYER && tmp!=op) {
            /* If a container that the player is currently using somehow gets
             * removed (most likely destroyed), update the player view
             * appropriately.
             */
            if (tmp->container==op) {
                CLEAR_FLAG(op, FLAG_APPLIED);
                tmp->container=NULL;
            }
            tmp->contr->socket.update_look=1;
        }
        /* See if player moving off should effect something */
        if (check_walk_off && ((op->move_type & tmp->move_off) &&
              (op->move_type & ~tmp->move_off & ~tmp->move_block)==0)) {

            move_apply(tmp, op, NULL);
            if (was_destroyed (op, tag)) {
                LOG (llevError, "BUG: remove_ob(): name %s, archname %s destroyed "
                     "leaving object\n", &tmp->name, &tmp->arch->name);
            }
        }

        /* Eneq(@csd.uu.se): Fixed this to skip tmp->above=tmp */

        if(tmp->above == tmp)
            tmp->above = NULL;
        last=tmp;
    }
    /* last == NULL of there are no objects on this space */
    if (last==NULL) {
        /* set P_NEED_UPDATE, otherwise update_position will complain.  In theory,
         * we could preserve the flags (GET_MAP_FLAGS), but update_position figures
         * those out anyways, and if there are any flags set right now, they won't
         * be correct anyways.
         */
        SET_MAP_FLAGS(op->map, op->x, op->y,  P_NEED_UPDATE);
        update_position(op->map, op->x, op->y);
    }
    else
        update_object(last, UP_OBJ_REMOVE);

    if(QUERY_FLAG(op,FLAG_BLOCKSVIEW)|| (op->glow_radius != 0)) 
        update_all_los(op->map, op->x, op->y);

}

/*
 * merge_ob(op,top):
 *
 * This function goes through all objects below and including top, and
 * merges op to the first matching object.
 * If top is NULL, it is calculated.
 * Returns pointer to object if it succeded in the merge, otherwise NULL
 */

object *merge_ob(object *op, object *top) {
  if(!op->nrof)
    return 0;
  if(top==NULL)
    for(top=op;top!=NULL&&top->above!=NULL;top=top->above);
  for(;top!=NULL;top=top->below) {
    if(top==op)
      continue;
    if (CAN_MERGE(op,top))
    {
      top->nrof+=op->nrof;
/*      CLEAR_FLAG(top,FLAG_STARTEQUIP);*/
      op->weight = 0; /* Don't want any adjustements now */
      remove_ob(op);
      free_object(op);
      return top;
    }
  }
  return NULL;
}

/*
 * same as insert_ob_in_map except it handle separate coordinates and do a clean
 * job preparing multi-part monsters
 */
object *insert_ob_in_map_at(object *op, mapstruct *m, object *originator, int flag, int x, int y){
    object* tmp;
    if (op->head)
        op=op->head;
    for (tmp=op;tmp;tmp=tmp->more){
        tmp->x=x+tmp->arch->clone.x;
        tmp->y=y+tmp->arch->clone.y;
    }
    return insert_ob_in_map (op, m, originator, flag);
}

/*
 * insert_ob_in_map (op, map, originator, flag):
 * This function inserts the object in the two-way linked list
 * which represents what is on a map.
 * The second argument specifies the map, and the x and y variables
 * in the object about to be inserted specifies the position.
 *
 * originator: Player, monster or other object that caused 'op' to be inserted
 * into 'map'.  May be NULL.
 *
 * flag is a bitmask about special things to do (or not do) when this
 * function is called.  see the object.h file for the INS_ values.
 * Passing 0 for flag gives proper default values, so flag really only needs
 * to be set if special handling is needed.
 *
 * Return value:
 *   new object if 'op' was merged with other object
 *   NULL if 'op' was destroyed
 *   just 'op' otherwise
 */

object *insert_ob_in_map (object *op, mapstruct *m, object *originator, int flag)
{
    object *tmp, *top, *floor=NULL;
    sint16 x,y;

    if (QUERY_FLAG (op, FLAG_FREED)) {
        LOG (llevError, "Trying to insert freed object!\n");
        return NULL;
    }
    if(m==NULL) {
        dump_object(op);
        LOG(llevError,"Trying to insert in null-map!\n%s\n",errmsg);
        return op;
    }
    if(out_of_map(m,op->x,op->y)) {
        dump_object(op);
        LOG(llevError,"Trying to insert object outside the map.\n%s\n", errmsg);
#ifdef MANY_CORES
        /* Better to catch this here, as otherwise the next use of this object
         * is likely to cause a crash.  Better to find out where it is getting
         * improperly inserted.
         */
        abort();
#endif
        return op;
    }
    if(!QUERY_FLAG(op,FLAG_REMOVED)) {
        dump_object(op);
        LOG(llevError,"Trying to insert (map) inserted object.\n%s\n", errmsg);
        return op;
    }
    if(op->more!=NULL) {
        /* The part may be on a different map. */

        object *more = op->more;

        /* We really need the caller to normalize coordinates - if
         * we set the map, that doesn't work if the location is within
         * a map and this is straddling an edge.  So only if coordinate
         * is clear wrong do we normalize it.
         */
        if (OUT_OF_REAL_MAP(more->map, more->x, more->y)) {
            more->map = get_map_from_coord(m, &more->x, &more->y);
        } else if (!more->map) {
            /* For backwards compatibility - when not dealing with tiled maps,
             * more->map should always point to the parent.
             */
            more->map = m;
        }

        if (insert_ob_in_map(more, more->map, originator, flag) == NULL) {
            if ( ! op->head)
                LOG (llevError, "BUG: insert_ob_in_map(): inserting op->more killed op\n");
            return NULL;
        }
    }
    CLEAR_FLAG(op,FLAG_REMOVED);

    /* Ideally, the caller figures this out.  However, it complicates a lot
     * of areas of callers (eg, anything that uses find_free_spot would now
     * need extra work
     */
    op->map=get_map_from_coord(m, &op->x, &op->y);
    x = op->x;
    y = op->y;

    /* this has to be done after we translate the coordinates.
     */
    if(op->nrof && !(flag & INS_NO_MERGE)) {
        for(tmp=GET_MAP_OB(op->map,x,y);tmp!=NULL;tmp=tmp->above)
            if (CAN_MERGE(op,tmp)) {
                op->nrof+=tmp->nrof;
                remove_ob(tmp);
                free_object(tmp);
            }
    }

    CLEAR_FLAG(op,FLAG_APPLIED); /* hack for fixing F_APPLIED in items of dead people */
    CLEAR_FLAG(op, FLAG_INV_LOCKED);
    if (!QUERY_FLAG(op, FLAG_ALIVE))
        CLEAR_FLAG(op, FLAG_NO_STEAL);

    if (flag & INS_BELOW_ORIGINATOR) { 
        if (originator->map != op->map || originator->x != op->x ||
            originator->y != op->y) {
            LOG(llevError,"insert_ob_in_map called with INS_BELOW_ORIGINATOR when originator not on same space!\n");
            abort();
        }
        op->above = originator;
        op->below = originator->below;
        if (op->below) op->below->above = op;
        else SET_MAP_OB(op->map, op->x, op->y, op);
        /* since *below* originator, no need to update top */
        originator->below = op;
    } else {
        /* If there are other objects, then */
        if((! (flag & INS_MAP_LOAD)) && ((top=GET_MAP_OB(op->map,op->x,op->y))!=NULL)) {
            object *last=NULL;
            /*
             * If there are multiple objects on this space, we do some trickier handling.
             * We've already dealt with merging if appropriate.
             * Generally, we want to put the new object on top. But if
             * flag contains INS_ABOVE_FLOOR_ONLY, once we find the last
             * floor, we want to insert above that and no further.
             * Also, if there are spell objects on this space, we stop processing
             * once we get to them.  This reduces the need to traverse over all of 
             * them when adding another one - this saves quite a bit of cpu time
             * when lots of spells are cast in one area.  Currently, it is presumed
             * that flying non pickable objects are spell objects.
             */

            while (top != NULL) {
                if (QUERY_FLAG(top, FLAG_IS_FLOOR) ||
                    QUERY_FLAG(top, FLAG_OVERLAY_FLOOR)) floor = top;
                if (QUERY_FLAG(top, FLAG_NO_PICK)
                    && (top->move_type & (MOVE_FLY_LOW |MOVE_FLY_HIGH))
                    && !QUERY_FLAG(top, FLAG_IS_FLOOR))
                  {
                      /* We insert above top, so we want this object below this */
                      top=top->below;
                      break;
                  }
                last = top;
                top = top->above;
            }
            /* Don't want top to be NULL, so set it to the last valid object */
            top = last;

            /* We let update_position deal with figuring out what the space
             * looks like instead of lots of conditions here.
             * makes things faster, and effectively the same result.
             */

            /* Have object 'fall below' other objects that block view.
             * Unless those objects are exits, type 66
             * If INS_ON_TOP is used, don't do this processing
             * Need to find the object that in fact blocks view, otherwise
             * stacking is a bit odd.
             */
            if (!(flag & INS_ON_TOP) &&
                (get_map_flags(op->map, NULL, op->x, op->y, NULL, NULL) & P_BLOCKSVIEW) && 
                (op->face && !op->face->visibility)) {
                for (last=top; last != floor; last=last->below)
                    if (QUERY_FLAG(last, FLAG_BLOCKSVIEW)&&(last->type != EXIT)) break;
                /* Check to see if we found the object that blocks view,
                 * and make sure we have a below pointer for it so that
                 * we can get inserted below this one, which requires we
                 * set top to the object below us.
                 */
                if (last && last->below && last != floor) top=last->below;
            }
        } /* If objects on this space */
        if (flag & INS_MAP_LOAD)
                top = GET_MAP_TOP(op->map,op->x,op->y);
        if (flag & INS_ABOVE_FLOOR_ONLY) top = floor;

        /* Top is the object that our object (op) is going to get inserted above.
         */

        /* First object on this space */
        if (!top) {
            op->above = GET_MAP_OB(op->map, op->x, op->y);
            if (op->above) op->above->below = op;
            op->below = NULL;
            SET_MAP_OB(op->map, op->x, op->y, op);
        } else { /* get inserted into the stack above top */
            op->above = top->above;
            if (op->above) op->above->below = op;
            op->below = top;
            top->above = op;
        }
        if (op->above==NULL)
            SET_MAP_TOP(op->map,op->x, op->y, op);
    } /* else not INS_BELOW_ORIGINATOR */

    if(op->type==PLAYER)
        op->contr->do_los=1;

    /* If we have a floor, we know the player, if any, will be above
     * it, so save a few ticks and start from there.
     */
    if (!(flag & INS_MAP_LOAD))
        for(tmp=floor?floor:GET_MAP_OB(op->map,op->x,op->y);tmp!=NULL;tmp=tmp->above) {
                if (tmp->type == PLAYER)
                tmp->contr->socket.update_look=1;
        }

    /* If this object glows, it may affect lighting conditions that are
     * visible to others on this map.  But update_all_los is really
     * an inefficient way to do this, as it means los for all players
     * on the map will get recalculated.  The players could very well
     * be far away from this change and not affected in any way -
     * this should get redone to only look for players within range,
     * or just updating the P_NEED_UPDATE for spaces within this area
     * of effect may be sufficient.
     */
    if(MAP_DARKNESS(op->map) && (op->glow_radius != 0)) 
        update_all_los(op->map, op->x, op->y);


    /* updates flags (blocked, alive, no magic, etc) for this map space */
    update_object(op,UP_OBJ_INSERT);


    /* Don't know if moving this to the end will break anything.  However,
     * we want to have update_look set above before calling this.
     *
     * check_move_on() must be after this because code called from
     * check_move_on() depends on correct map flags (so functions like
     * blocked() and wall() work properly), and these flags are updated by
     * update_object().
     */

    /* if this is not the head or flag has been passed, don't check walk on status */

    if (!(flag & INS_NO_WALK_ON) && !op->head) {
        if (check_move_on(op, originator))
            return NULL;

        /* If we are a multi part object, lets work our way through the check
         * walk on's.
         */
        for (tmp=op->more; tmp!=NULL; tmp=tmp->more)
            if (check_move_on (tmp, originator))
                return NULL;
    }
    return op;
}

/* this function inserts an object in the map, but if it
 *  finds an object of its own type, it'll remove that one first. 
 *  op is the object to insert it under:  supplies x and the map.
 */
void replace_insert_ob_in_map(const char *arch_string, object *op) {
    object *tmp;
    object *tmp1;

    /* first search for itself and remove any old instances */

    for(tmp=GET_MAP_OB(op->map,op->x,op->y); tmp!=NULL; tmp=tmp->above) {
        if(!strcmp(tmp->arch->name,arch_string)) /* same archetype */ {
            remove_ob(tmp);
            free_object(tmp);
        }
    }

    tmp1=arch_to_object(find_archetype(arch_string));

  
    tmp1->x = op->x; tmp1->y = op->y;
    insert_ob_in_map(tmp1,op->map,op,0);
}        

/*
 * get_split_ob(ob,nr) splits up ob into two parts.  The part which
 * is returned contains nr objects, and the remaining parts contains
 * the rest (or is removed and freed if that number is 0).
 * On failure, NULL is returned, and the reason put into the
 * global static errmsg array.
 */

object *get_split_ob(object *orig_ob, uint32 nr) {
    object *newob;
    int is_removed = (QUERY_FLAG (orig_ob, FLAG_REMOVED) != 0);

    if(orig_ob->nrof<nr) {
        sprintf(errmsg,"There are only %d %ss.",
            orig_ob->nrof?orig_ob->nrof:1, &orig_ob->name);
        return NULL;
    }
    newob = object_create_clone(orig_ob);
    if((orig_ob->nrof-=nr)<1) {
        if ( ! is_removed)
            remove_ob(orig_ob);
        free_object2(orig_ob, 1);
    }
    else if ( ! is_removed) {
        if(orig_ob->env!=NULL)
            sub_weight (orig_ob->env,orig_ob->weight*nr);
        if (orig_ob->env == NULL && orig_ob->map->in_memory!=MAP_IN_MEMORY) {
            strcpy(errmsg, "Tried to split object whose map is not in memory.");
            LOG(llevDebug,
                    "Error, Tried to split object whose map is not in memory.\n");
            return NULL;
        }
    }
    newob->nrof=nr;

    return newob;
}

/*
 * decrease_ob_nr(object, number) decreases a specified number from
 * the amount of an object.  If the amount reaches 0, the object
 * is subsequently removed and freed.
 *
 * Return value: 'op' if something is left, NULL if the amount reached 0
 */

object *decrease_ob_nr (object *op, uint32 i)
{
    object *tmp;
    player *pl;

    if (i == 0)   /* objects with op->nrof require this check */
        return op;

    if (i > op->nrof)
        i = op->nrof;

    if (QUERY_FLAG (op, FLAG_REMOVED))
    {
        op->nrof -= i;
    }
    else if (op->env != NULL)
    {
        /* is this object in the players inventory, or sub container
         * therein?
         */
        tmp = is_player_inv (op->env);
        /* nope.  Is this a container the player has opened?
         * If so, set tmp to that player.
         * IMO, searching through all the players will mostly
         * likely be quicker than following op->env to the map,
         * and then searching the map for a player.
         */
        if (!tmp) {
            for (pl=first_player; pl; pl=pl->next)
                if (pl->ob->container == op->env) break;
            if (pl) tmp=pl->ob;
            else tmp=NULL;
        }

        if (i < op->nrof) {
            sub_weight (op->env, op->weight * i);
            op->nrof -= i;
            if (tmp) {
                esrv_send_item(tmp, op);
            }
        } else {
            remove_ob (op);
            op->nrof = 0;
            if (tmp) {
                esrv_del_item(tmp->contr, op->count);
            }
        }
    }
    else 
    {
        object *above = op->above;

        if (i < op->nrof) {
            op->nrof -= i;
        } else {
            remove_ob (op);
            op->nrof = 0;
        }
        /* Since we just removed op, op->above is null */
        for (tmp = above; tmp != NULL; tmp = tmp->above)
            if (tmp->type == PLAYER) {
                if (op->nrof)
                    esrv_send_item(tmp, op);
                else
                    esrv_del_item(tmp->contr, op->count);
            }
    }

    if (op->nrof) {
        return op;
    } else {
        free_object (op);
        return NULL;
    }
}

/*
 * add_weight(object, weight) adds the specified weight to an object,
 * and also updates how much the environment(s) is/are carrying.
 */

void add_weight (object *op, signed long weight) {
  while (op!=NULL) {
    if (op->type == CONTAINER) {
      weight=(signed long)(weight*(100-op->stats.Str)/100);
    }
    op->carrying+=weight;
    op=op->env;
  }
}

/*
 * insert_ob_in_ob(op,environment):
 *   This function inserts the object op in the linked list
 *   inside the object environment.
 *
 * Eneq(@csd.uu.se): Altered insert_ob_in_ob to make things picked up enter 
 * the inventory at the last position or next to other objects of the same
 * type.
 * Frank: Now sorted by type, archetype and magic!
 *
 * The function returns now pointer to inserted item, and return value can 
 * be != op, if items are merged. -Tero
 */

object *insert_ob_in_ob(object *op,object *where) {
  object *tmp, *otmp;

  if(!QUERY_FLAG(op,FLAG_REMOVED)) {
    dump_object(op);
    LOG(llevError,"Trying to insert (ob) inserted object.\n%s\n", errmsg);
    return op;
  }
  if(where==NULL) {
    dump_object(op);
    LOG(llevError,"Trying to put object in NULL.\n%s\n", errmsg);
    return op;
  }
  if (where->head) {
    LOG(llevDebug, 
        "Warning: Tried to insert object wrong part of multipart object.\n");
    where = where->head;
  }
  if (op->more) {
    LOG(llevError, "Tried to insert multipart object %s (%d)\n",
        &op->name, op->count);
    return op;
  }
  CLEAR_FLAG(op, FLAG_OBJ_ORIGINAL);
  CLEAR_FLAG(op, FLAG_REMOVED);
  if(op->nrof) {
    for(tmp=where->inv;tmp!=NULL;tmp=tmp->below)
      if ( CAN_MERGE(tmp,op) ) {
        /* return the original object and remove inserted object
           (client needs the original object) */
        tmp->nrof += op->nrof;
        /* Weight handling gets pretty funky.  Since we are adding to
         * tmp->nrof, we need to increase the weight.
         */
        add_weight (where, op->weight*op->nrof);
        SET_FLAG(op, FLAG_REMOVED);
        free_object(op); /* free the inserted object */
        op = tmp;
        remove_ob (op); /* and fix old object's links */
        CLEAR_FLAG(op, FLAG_REMOVED);
        break;
      }

    /* I assume combined objects have no inventory
     * We add the weight - this object could have just been removed
     * (if it was possible to merge).  calling remove_ob will subtract
     * the weight, so we need to add it in again, since we actually do
     * the linking below
     */
    add_weight (where, op->weight*op->nrof);
  } else
    add_weight (where, (op->weight+op->carrying));

  otmp=is_player_inv(where);
  if (otmp&&otmp->contr!=NULL) {
    if (!QUERY_FLAG(otmp,FLAG_NO_FIX_PLAYER))
      fix_player(otmp);
  }

  op->map=NULL;
  op->env=where;
  op->above=NULL;
  op->below=NULL;
  op->x=0,op->y=0;

  /* reset the light list and los of the players on the map */
  if((op->glow_radius!=0)&&where->map)
  {
#ifdef DEBUG_LIGHTS
      LOG(llevDebug, " insert_ob_in_ob(): got %s to insert in map/op\n",
        op->name);
#endif /* DEBUG_LIGHTS */ 
      if (MAP_DARKNESS(where->map)) update_all_los(where->map, where->x, where->y);
  }

  /* Client has no idea of ordering so lets not bother ordering it here.
   * It sure simplifies this function...
   */
  if (where->inv==NULL)
      where->inv=op;
  else {
      op->below = where->inv;
      op->below->above = op;
      where->inv = op;
  }
  return op;
}

/*
 * Checks if any objects has a move_type that matches objects
 * that effect this object on this space.  Call apply() to process
 * these events.
 *
 * Any speed-modification due to SLOW_MOVE() of other present objects
 * will affect the speed_left of the object.
 *
 * originator: Player, monster or other object that caused 'op' to be inserted
 * into 'map'.  May be NULL.
 *
 * Return value: 1 if 'op' was destroyed, 0 otherwise.
 *
 * 4-21-95 added code to check if appropriate skill was readied - this will
 * permit faster movement by the player through this terrain. -b.t.
 *
 * MSW 2001-07-08: Check all objects on space, not just those below
 * object being inserted.  insert_ob_in_map may not put new objects
 * on top.
 */

int check_move_on (object *op, object *originator)
{
    object *tmp;
    tag_t tag;
    mapstruct *m=op->map;
    int x=op->x, y=op->y;
    MoveType    move_on, move_slow, move_block;

    if(QUERY_FLAG(op,FLAG_NO_APPLY))
        return 0;

    tag = op->count;

    move_on = GET_MAP_MOVE_ON(op->map, op->x, op->y);
    move_slow = GET_MAP_MOVE_SLOW(op->map, op->x, op->y);
    move_block = GET_MAP_MOVE_BLOCK(op->map, op->x, op->y);

    /* if nothing on this space will slow op down or be applied,
     * no need to do checking below.    have to make sure move_type
     * is set, as lots of objects don't have it set - we treat that
     * as walking.
     */
    if (op->move_type && !(op->move_type & move_on) && !(op->move_type & move_slow))
        return 0;

    /* This is basically inverse logic of that below - basically,
     * if the object can avoid the move on or slow move, they do so,
     * but can't do it if the alternate movement they are using is
     * blocked.  Logic on this seems confusing, but does seem correct.
     */
    if ((op->move_type & ~move_on & ~move_block) != 0 &&
        (op->move_type & ~move_slow & ~move_block) != 0) return 0;

    /* The objects have to be checked from top to bottom.
     * Hence, we first go to the top: 
     */

    for (tmp=GET_MAP_OB(op->map, op->x, op->y); tmp!=NULL &&
         tmp->above!=NULL; tmp=tmp->above) {
        /* Trim the search when we find the first other spell effect 
         * this helps performance so that if a space has 50 spell objects,
         * we don't need to check all of them.
         */
        if ((tmp->move_type & MOVE_FLY_LOW) && QUERY_FLAG(tmp, FLAG_NO_PICK)) break;
    }
    for(;tmp!=NULL; tmp=tmp->below) {
        if (tmp == op) continue;    /* Can't apply yourself */

        /* Check to see if one of the movement types should be slowed down.
         * Second check makes sure that the movement types not being slowed
         * (~slow_move) is not blocked on this space - just because the
         * space doesn't slow down swimming (for example), if you can't actually
         * swim on that space, can't use it to avoid the penalty.
         */
        if (!QUERY_FLAG(op, FLAG_WIZPASS)) {
            if ((!op->move_type && tmp->move_slow & MOVE_WALK) ||
                ((op->move_type & tmp->move_slow) &&
                (op->move_type & ~tmp->move_slow & ~tmp->move_block) == 0)) {

                float diff;

                diff = tmp->move_slow_penalty*FABS(op->speed);
                if (op->type == PLAYER) {
                    if ((QUERY_FLAG(tmp, FLAG_IS_HILLY) && find_skill_by_number(op, SK_CLIMBING)) ||
                        (QUERY_FLAG(tmp, FLAG_IS_WOODED) && find_skill_by_number(op, SK_WOODSMAN))) {
                        diff /= 4.0;
                    }
                }
                op->speed_left -= diff;
            }
        }

        /* Basically same logic as above, except now for actual apply. */
        if ((!op->move_type && tmp->move_on & MOVE_WALK) ||
            ((op->move_type & tmp->move_on) &&
            (op->move_type & ~tmp->move_on & ~tmp->move_block)==0)) {

            move_apply(tmp, op, originator);
            if (was_destroyed (op, tag))
                return 1;

                /* what the person/creature stepped onto has moved the object
                 * someplace new.  Don't process any further - if we did,
                 * have a feeling strange problems would result.
                 */
                if (op->map != m || op->x != x || op->y != y) return 0;
        }
    }
    return 0;
}

/*
 * present_arch(arch, map, x, y) searches for any objects with
 * a matching archetype at the given map and coordinates.
 * The first matching object is returned, or NULL if none.
 */

object *present_arch(const archetype *at, mapstruct *m, int x, int y) {
  object *tmp;
  if(m==NULL || out_of_map(m,x,y)) {
    LOG(llevError,"Present_arch called outside map.\n");
    return NULL;
  }
  for(tmp=GET_MAP_OB(m,x,y); tmp != NULL; tmp = tmp->above)
    if(tmp->arch == at)
      return tmp;
  return NULL;
}

/*
 * present(type, map, x, y) searches for any objects with
 * a matching type variable at the given map and coordinates.
 * The first matching object is returned, or NULL if none.
 */

object *present(unsigned char type,mapstruct *m, int x,int y) {
  object *tmp;
  if(out_of_map(m,x,y)) {
    LOG(llevError,"Present called outside map.\n");
    return NULL;
  }
  for(tmp=GET_MAP_OB(m,x,y);tmp!=NULL;tmp=tmp->above)
    if(tmp->type==type)
      return tmp;
  return NULL;
}

/*
 * present_in_ob(type, object) searches for any objects with
 * a matching type variable in the inventory of the given object.
 * The first matching object is returned, or NULL if none.
 */

object *present_in_ob(unsigned char type, const object *op) {
  object *tmp;
  for(tmp=op->inv;tmp!=NULL;tmp=tmp->below)
    if(tmp->type==type)
      return tmp;
  return NULL;
}

/*
 * present_in_ob (type, str, object) searches for any objects with
 * a matching type & name variable in the inventory of the given object.
 * The first matching object is returned, or NULL if none.
 * This is mostly used by spell effect code, so that we only
 * have one spell effect at a time.
 * type can be used to narrow the search - if type is set,
 * the type must also match.  -1 can be passed for the type,
 * in which case the type does not need to pass.
 * str is the string to match against.  Note that we match against
 * the object name, not the archetype name.  this is so that the
 * spell code can use one object type (force), but change it's name
 * to be unique.
 */

object *present_in_ob_by_name(int type, const char *str, const object *op) {
    object *tmp;

    for(tmp=op->inv; tmp!=NULL; tmp=tmp->below) {
        if ((type==-1 || tmp->type==type) && (!strcmp(str, tmp->name)))
            return tmp;
    }
    return NULL;
}

/*
 * present_arch_in_ob(archetype, object) searches for any objects with
 * a matching archetype in the inventory of the given object.
 * The first matching object is returned, or NULL if none.
 */

object *present_arch_in_ob(const archetype *at, const object *op)  {
  object *tmp;
  for(tmp=op->inv;tmp!=NULL;tmp=tmp->below)
    if( tmp->arch == at)
      return tmp;
  return NULL;
}

/*
 * activate recursively a flag on an object inventory
 */
void flag_inv(object*op, int flag){
    object *tmp;
    if(op->inv)
      for(tmp = op->inv; tmp != NULL; tmp = tmp->below){
        SET_FLAG(tmp, flag);
        flag_inv(tmp,flag);
      }
}/*
 * desactivate recursively a flag on an object inventory
 */
void unflag_inv(object*op, int flag){
    object *tmp;
    if(op->inv)
      for(tmp = op->inv; tmp != NULL; tmp = tmp->below){
        CLEAR_FLAG(tmp, flag);
        unflag_inv(tmp,flag);
      }
}

/*
 * set_cheat(object) sets the cheat flag (WAS_WIZ) in the object and in
 * all it's inventory (recursively).
 * If checksums are used, a player will get set_cheat called for
 * him/her-self and all object carried by a call to this function.
 */

void set_cheat(object *op) {
    SET_FLAG(op, FLAG_WAS_WIZ);
    flag_inv(op, FLAG_WAS_WIZ);
}

/*
 * find_free_spot(object, map, x, y, start, stop) will search for
 * a spot at the given map and coordinates which will be able to contain
 * the given object.  start and stop specifies how many squares
 * to search (see the freearr_x/y[] definition).
 * It returns a random choice among the alternatives found.
 * start and stop are where to start relative to the free_arr array (1,9
 * does all 4 immediate directions).  This returns the index into the
 * array of the free spot, -1 if no spot available (dir 0 = x,y)
 * Note - this only checks to see if there is space for the head of the
 * object - if it is a multispace object, this should be called for all
 * pieces.
 * Note2: This function does correctly handle tiled maps, but does not
 * inform the caller.  However, insert_ob_in_map will update as
 * necessary, so the caller shouldn't need to do any special work.
 * Note - updated to take an object instead of archetype - this is necessary
 * because arch_blocked (now ob_blocked) needs to know the movement type
 * to know if the space in question will block the object.  We can't use
 * the archetype because that isn't correct if the monster has been 
 * customized, changed states, etc.
 */

int find_free_spot(const object *ob, mapstruct *m,int x,int y,int start,int stop) {
    int i,index=0, flag;
    static int altern[SIZEOFFREE];

    for(i=start;i<stop;i++) {
        flag = ob_blocked(ob,m,x+freearr_x[i],y+freearr_y[i]);
        if(!flag)
            altern[index++]=i;

        /* Basically, if we find a wall on a space, we cut down the search size.
         * In this way, we won't return spaces that are on another side of a wall.
         * This mostly work, but it cuts down the search size in all directions - 
         * if the space being examined only has a wall to the north and empty
         * spaces in all the other directions, this will reduce the search space
         * to only the spaces immediately surrounding the target area, and
         * won't look 2 spaces south of the target space.
         */
        else if ((flag & AB_NO_PASS) && maxfree[i]<stop)
            stop=maxfree[i];
    }
    if(!index) return -1;
    return altern[RANDOM()%index];
}

/*
 * find_first_free_spot(archetype, mapstruct, x, y) works like
 * find_free_spot(), but it will search max number of squares.
 * But it will return the first available spot, not a random choice.
 * Changed 0.93.2: Have it return -1 if there is no free spot available.
 */

int find_first_free_spot(const object *ob, mapstruct *m,int x,int y) {
    int i;
    for(i=0;i<SIZEOFFREE;i++) {
        if(!ob_blocked(ob,m,x+freearr_x[i],y+freearr_y[i]))
            return i;
    }
    return -1;
}

/*
 * The function permute(arr, begin, end) randomly reorders the array
 * arr[begin..end-1].
 */
static void permute(int *arr, int begin, int end)
{
    int i, j, tmp, len;

    len = end-begin;
    for(i = begin; i < end; i++)
    {
        j = begin+RANDOM()%len;

        tmp = arr[i];
        arr[i] = arr[j];
        arr[j] = tmp;
    }
}

/* new function to make monster searching more efficient, and effective! 
 * This basically returns a randomized array (in the passed pointer) of
 * the spaces to find monsters.  In this way, it won't always look for
 * monsters to the north first.  However, the size of the array passed
 * covers all the spaces, so within that size, all the spaces within
 * the 3x3 area will be searched, just not in a predictable order.
 */
void get_search_arr(int *search_arr)
{
    int i;

    for(i = 0; i < SIZEOFFREE; i++)
    {
        search_arr[i] = i;
    }

    permute(search_arr, 1, SIZEOFFREE1+1);
    permute(search_arr, SIZEOFFREE1+1, SIZEOFFREE2+1);
    permute(search_arr, SIZEOFFREE2+1, SIZEOFFREE);
}

/*
 * find_dir(map, x, y, exclude) will search some close squares in the
 * given map at the given coordinates for live objects.
 * It will not considered the object given as exclude among possible
 * live objects.
 * It returns the direction toward the first/closest live object if finds
 * any, otherwise 0.
 * Perhaps incorrectly, but I'm making the assumption that exclude
 * is actually want is going to try and move there.  We need this info
 * because we have to know what movement the thing looking to move
 * there is capable of.
 */

int find_dir(mapstruct *m, int x, int y, object *exclude) {
    int i,max=SIZEOFFREE, mflags;
    sint16 nx, ny;
    object *tmp;
    mapstruct *mp;
    MoveType    blocked, move_type;

    if (exclude && exclude->head) {
        exclude = exclude->head;
        move_type = exclude->move_type;
    } else {
        /* If we don't have anything, presume it can use all movement types. */
        move_type=MOVE_ALL;
    }

    for(i=1;i<max;i++) {
        mp = m;
        nx = x + freearr_x[i];
        ny = y + freearr_y[i];

        mflags = get_map_flags(m, &mp, nx, ny, &nx, &ny);
        if (mflags & P_OUT_OF_MAP) {
            max = maxfree[i];
        } else {
            blocked = GET_MAP_MOVE_BLOCK(mp, nx, ny);

            if ((move_type & blocked) == move_type) {
                max=maxfree[i];
            } else if (mflags & P_IS_ALIVE) {
                for (tmp=GET_MAP_OB(mp,nx,ny); tmp!= NULL; tmp=tmp->above) {
                    if ((QUERY_FLAG(tmp,FLAG_MONSTER) ||  tmp->type==PLAYER) &&
                        (tmp != exclude ||(tmp->head && tmp->head != exclude))) {
                        break;
                    }
                }
                if(tmp) {
                    return freedir[i];
                }
            }
        }
    }
    return 0;
}

/*
 * distance(object 1, object 2) will return the square of the
 * distance between the two given objects.
 */

int distance(const object *ob1, const object *ob2) {
  int i;
  i= (ob1->x - ob2->x)*(ob1->x - ob2->x)+
         (ob1->y - ob2->y)*(ob1->y - ob2->y);
  return i;
}

/*
 * find_dir_2(delta-x,delta-y) will return a direction in which
 * an object which has subtracted the x and y coordinates of another
 * object, needs to travel toward it.
 */

int find_dir_2(int x, int y) {
  int q;

  if(y)
    q=x*100/y;
  else if (x)
    q= -300*x;
  else
    return 0;

  if(y>0) {
    if(q < -242)
      return 3 ;
    if (q < -41)
      return 2 ;
    if (q < 41)
      return 1 ;
    if (q < 242)
      return 8 ;
    return 7 ;
  }

  if (q < -242)
    return 7 ;
  if (q < -41)
    return 6 ;
  if (q < 41)
    return 5 ;
  if (q < 242)
    return 4 ;

  return 3 ;
}

/*
 * absdir(int): Returns a number between 1 and 8, which represent
 * the "absolute" direction of a number (it actually takes care of
 * "overflow" in previous calculations of a direction).
 */

int absdir(int d) {
  while(d<1) d+=8;
  while(d>8) d-=8;
  return d;
}

/*
 * dirdiff(dir1, dir2) returns how many 45-degrees differences there is
 * between two directions (which are expected to be absolute (see absdir())
 */

int dirdiff(int dir1, int dir2) {
  int d;
  d = abs(dir1 - dir2);
  if(d>4)
    d = 8 - d;
  return d;
}

/* peterm:
 * do LOS stuff for ball lightning.  Go after the closest VISIBLE monster.
 * Basically, this is a table of directions, and what directions
 * one could go to go back to us.  Eg, entry 15 below is 4, 14, 16.
 * This basically means that if direction is 15, then it could either go
 * direction 4, 14, or 16 to get back to where we are.
 * Moved from spell_util.c to object.c with the other related direction
 * functions.
 */

int reduction_dir[SIZEOFFREE][3] = {
  {0,0,0}, /* 0 */ 
  {0,0,0}, /* 1 */
  {0,0,0}, /* 2 */
  {0,0,0}, /* 3 */
  {0,0,0}, /* 4 */
  {0,0,0}, /* 5 */
  {0,0,0}, /* 6 */
  {0,0,0}, /* 7 */
  {0,0,0}, /* 8 */
  {8,1,2}, /* 9 */
  {1,2,-1}, /* 10 */
  {2,10,12}, /* 11 */
  {2,3,-1}, /* 12 */
  {2,3,4}, /* 13 */
  {3,4,-1}, /* 14 */
  {4,14,16}, /* 15 */
  {5,4,-1}, /* 16 */
  {4,5,6}, /* 17 */
  {6,5,-1}, /* 18 */
  {6,20,18}, /* 19 */
  {7,6,-1}, /* 20 */
  {6,7,8}, /* 21 */
  {7,8,-1}, /* 22 */
  {8,22,24}, /* 23 */
  {8,1,-1}, /* 24 */
  {24,9,10}, /* 25 */
  {9,10,-1}, /* 26 */
  {10,11,-1}, /* 27 */
  {27,11,29}, /* 28 */
  {11,12,-1}, /* 29 */
  {12,13,-1}, /* 30 */
  {12,13,14}, /* 31 */
  {13,14,-1}, /* 32 */
  {14,15,-1}, /* 33 */
  {33,15,35}, /* 34 */
  {16,15,-1}, /* 35 */
  {17,16,-1}, /* 36 */
  {18,17,16}, /* 37 */
  {18,17,-1}, /* 38 */
  {18,19,-1}, /* 39 */
  {41,19,39}, /* 40 */
  {19,20,-1}, /* 41 */
  {20,21,-1}, /* 42 */
  {20,21,22}, /* 43 */
  {21,22,-1}, /* 44 */
  {23,22,-1}, /* 45 */
  {45,47,23}, /* 46 */
  {23,24,-1}, /* 47 */
  {24,9,-1}}; /* 48 */

/* Recursive routine to step back and see if we can
 * find a path to that monster that we found.  If not,
 * we don't bother going toward it.  Returns 1 if we
 * can see a direct way to get it
 * Modified to be map tile aware -.MSW
 */
 

int can_see_monsterP(mapstruct *m, int x, int y,int dir) {
    sint16 dx, dy;
    int mflags;

    if(dir<0) return 0;  /* exit condition:  invalid direction */

    dx = x + freearr_x[dir];
    dy = y + freearr_y[dir];

    mflags = get_map_flags(m, &m, dx, dy, &dx, &dy);

    /* This functional arguably was incorrect before - it was
     * checking for P_WALL - that was basically seeing if
     * we could move to the monster - this is being more
     * literal on if we can see it.  To know if we can actually
     * move to the monster, we'd need the monster passed in or
     * at least its move type.
     */
    if (mflags & (P_OUT_OF_MAP | P_BLOCKSVIEW)) return 0;

    /* yes, can see. */
    if(dir < 9) return 1;
    return can_see_monsterP(m, x, y, reduction_dir[dir][0]) |
        can_see_monsterP(m,x,y, reduction_dir[dir][1]) |
        can_see_monsterP(m,x,y, reduction_dir[dir][2]);
}
  
  
/*
 * can_pick(picker, item): finds out if an object is possible to be
 * picked up by the picker.  Returnes 1 if it can be
 * picked up, otherwise 0.
 *
 * Cf 0.91.3 - don't let WIZ's pick up anything - will likely cause
 * core dumps if they do.
 *
 * Add a check so we can't pick up invisible objects (0.93.8)
 */

int can_pick(const object *who, const object *item) {
  return /*QUERY_FLAG(who,FLAG_WIZ)||*/
         (item->weight>0&&!QUERY_FLAG(item,FLAG_NO_PICK)&&
         !QUERY_FLAG(item,FLAG_ALIVE)&&!item->invisible &&
          (who->type==PLAYER||item->weight<who->weight/3));
}


/*
 * create clone from object to another
 */
object *object_create_clone (object *asrc) {
    object *dst = NULL,*tmp,*src,*part,*prev, *item;

    if(!asrc) return NULL;
    src = asrc;
    if(src->head)
        src = src->head;

    prev = NULL;
    for(part = src; part; part = part->more) {
        tmp = get_object();
        copy_object(part,tmp);
        tmp->x -= src->x;
        tmp->y -= src->y;
        if(!part->head) {
            dst = tmp;
            tmp->head = NULL;
        } else {
            tmp->head = dst;
        }
        tmp->more = NULL;
        if(prev)
            prev->more = tmp;
        prev = tmp;
    }
    /*** copy inventory ***/
    for(item = src->inv; item; item = item->below) {
        (void) insert_ob_in_ob(object_create_clone(item),dst);
    }

    return dst;
}

/* return true if the object was destroyed, 0 otherwise */
int was_destroyed (const object *op, tag_t old_tag)
{
    /* checking for FLAG_FREED isn't necessary, but makes this function more
     * robust */
    return op->count != old_tag || QUERY_FLAG (op, FLAG_FREED);
}

/* GROS - Creates an object using a string representing its content.         */
/* Basically, we save the content of the string to a temp file, then call    */
/* load_object on it. I admit it is a highly inefficient way to make things, */
/* but it was simple to make and allows reusing the load_object function.    */
/* Remember not to use load_object_str in a time-critical situation.         */
/* Also remember that multiparts objects are not supported for now.          */

object* load_object_str(const char *obstr)
{
    object *op;
    char filename[MAX_BUF];
    sprintf(filename,"%s/cfloadobstr2044",settings.tmpdir);

    FILE *tempfile=fopen(filename,"w");
    if (tempfile == NULL)
    {
        LOG(llevError,"Error - Unable to access load object temp file\n");
        return NULL;
    };
    fprintf(tempfile,obstr);
    fclose(tempfile);

    op=get_object();

    object_thawer thawer (filename);
    if (thawer)
      load_object(thawer,op,LO_NEWFILE,0);
    LOG(llevDebug," load str completed, object=%s\n", &op->name);
    CLEAR_FLAG(op,FLAG_REMOVED);

    return op;
}

/* This returns the first object in who's inventory that
 * has the same type and subtype match.
 * returns NULL if no match.
 */
object *find_obj_by_type_subtype(const object *who, int type, int subtype)
{
    object *tmp;

    for (tmp=who->inv; tmp; tmp=tmp->below)
        if (tmp->type == type && tmp->subtype == subtype) return tmp;

    return NULL;
}

/* If ob has a field named key, return the link from the list,
 * otherwise return NULL. 
 *
 * key must be a passed in shared string - otherwise, this won't
 * do the desired thing.
 */
key_value * get_ob_key_link(const object * ob, const char * key) {
    key_value * link;
    
    for (link = ob->key_values; link != NULL; link = link->next) {
        if (link->key == key) {
            return link;
        }
    }
    
    return NULL;
}  

/* 
 * Returns the value of op has an extra_field for key, or NULL.
 *
 * The argument doesn't need to be a shared string.
 *
 * The returned string is shared.
 */
const char * get_ob_key_value(const object * op, const char * const key) {
    key_value * link;
    const char * canonical_key;
    
    canonical_key = shstr::find (key);
    
    if (canonical_key == NULL) {
        /* 1. There being a field named key on any object
         *    implies there'd be a shared string to find.
         * 2. Since there isn't, no object has this field.
         * 3. Therefore, *this* object doesn't have this field.
         */
        return NULL;
    }

    /* This is copied from get_ob_key_link() above -
     * only 4 lines, and saves the function call overhead.
     */
    for (link = op->key_values; link != NULL; link = link->next) {
        if (link->key == canonical_key) {
            return link->value;
        }
    }
    return NULL;
}


/*
 * Updates the canonical_key in op to value.
 *
 * canonical_key is a shared string (value doesn't have to be).
 *
 * Unless add_key is TRUE, it won't add fields, only change the value of existing
 * keys.
 *
 * Returns TRUE on success.
 */
int set_ob_key_value_s(object * op, const shstr &canonical_key, const char * value, int add_key) {
    key_value * field = NULL, *last=NULL;
    
    for (field=op->key_values; field != NULL; field=field->next) {
        if (field->key != canonical_key) {
            last = field;
            continue;
        }
    
        if (value) 
            field->value = value;
        else {
            /* Basically, if the archetype has this key set,
             * we need to store the null value so when we save
             * it, we save the empty value so that when we load,
             * we get this value back again.
             */
            if (get_ob_key_link (&op->arch->clone, canonical_key))
              field->value = 0;
            else
              {
                if (last) last->next = field->next;
                else op->key_values = field->next;

                delete field;
              }
        }
        return TRUE;
    }
    /* IF we get here, key doesn't exist */

    /* No field, we'll have to add it. */
    
    if (!add_key) {
        return FALSE;
    }
    /* There isn't any good reason to store a null
     * value in the key/value list.  If the archetype has
     * this key, then we should also have it, so shouldn't
     * be here.  If user wants to store empty strings,
     * should pass in ""
     */
    if (value == NULL) return TRUE;
    
    field = new key_value;
    
    field->key   = canonical_key;
    field->value = value;
    /* Usual prepend-addition. */
    field->next = op->key_values;
    op->key_values = field;
    
    return TRUE;
}

/*
 * Updates the key in op to value.
 *
 * If add_key is FALSE, this will only update existing keys,
 * and not add new ones.
 * In general, should be little reason FALSE is ever passed in for add_key
 *
 * Returns TRUE on success.
 */
int set_ob_key_value(object * op, const char *key, const char * value, int add_key)
{
  shstr key_ (key);
  return set_ob_key_value_s (op, key_, value, add_key);
}
Revision:	1.12
Committed:	Sun Sep 3 14:33:47 2006 UTC (17 years, 8 months ago) by elmex
Content type:	text/plain
Branch:	MAIN
Changes since 1.11:	+1 -10 lines
Log Message:	removed ox/oy, and then added shstr stuff to the recipes in alchemy