server/common/map.C

/*
 * static char *rcsid_map_c =
 *   "$Id: map.C,v 1.21 2006-09-03 22:45:55 root Exp $";
 */

/*
    CrossFire, A Multiplayer game for X-windows

    Copyright (C) 2001-2003 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
*/


#include <global.h>
#include <funcpoint.h>

#include <loader.h>
#ifndef WIN32 /* ---win32 exclude header */
#include <unistd.h>
#endif /* win32 */

#include "path.h"


extern int nrofallocobjects,nroffreeobjects;

/*
 * Returns the mapstruct which has a name matching the given argument.
 * return NULL if no match is found.
 */

mapstruct *has_been_loaded (const char *name) {
    mapstruct *map;

    if (!name || !*name) 
        return 0;
    for (map = first_map; map; map = map->next)
        if (!strcmp (name, map->path))
            break;
    return (map);
}

/*
 * This makes a path absolute outside the world of Crossfire.
 * In other words, it prepends LIBDIR/MAPDIR/ to the given path
 * and returns the pointer to a static array containing the result.
 * it really should be called create_mapname
 */

const char *create_pathname (const char *name) {
    static char buf[MAX_BUF];

    /* Why?  having extra / doesn't confuse unix anyplace?  Dependancies
     * someplace else in the code? msw 2-17-97
     */
    if (*name == '/')
      sprintf (buf, "%s/%s%s", settings.datadir, settings.mapdir, name);
    else
      sprintf (buf, "%s/%s/%s", settings.datadir, settings.mapdir, name);
    return (buf);
}

/*
 * same as create_pathname, but for the overlay maps.
 */

const char *create_overlay_pathname (const char *name) {
    static char buf[MAX_BUF];

    /* Why?  having extra / doesn't confuse unix anyplace?  Dependancies
     * someplace else in the code? msw 2-17-97
     */
    if (*name == '/')
      sprintf (buf, "%s/%s%s", settings.localdir, settings.mapdir, name);
    else
      sprintf (buf, "%s/%s/%s", settings.localdir, settings.mapdir, name);
    return (buf);
}

/*
 * same as create_pathname, but for the template maps.
 */

const char *create_template_pathname (const char *name) {
    static char buf[MAX_BUF];

    /* Why?  having extra / doesn't confuse unix anyplace?  Dependancies
     * someplace else in the code? msw 2-17-97
     */
    if (*name == '/')
      sprintf (buf, "%s/%s%s", settings.localdir, settings.templatedir, name);
    else
      sprintf (buf, "%s/%s/%s", settings.localdir, settings.templatedir, name);
    return (buf);
}

/*
 * This makes absolute path to the itemfile where unique objects
 * will be saved. Converts '/' to '@'. I think it's essier maintain
 * files than full directory structure, but if this is problem it can 
 * be changed.
 */
static const char *create_items_path (const char *s) {
    static char buf[MAX_BUF];
    char *t;
    
    if (*s == '/')
      s++;

    sprintf (buf, "%s/%s/", settings.localdir, settings.uniquedir);

    for (t=buf+strlen(buf); *s; s++,t++)
      if (*s == '/')
          *t = '@';
      else 
          *t = *s;
    *t = 0;
    return (buf);  
}


/*
 * This function checks if a file with the given path exists.
 * -1 is returned if it fails, otherwise the mode of the file
 * is returned.
 * It tries out all the compression suffixes listed in the uncomp[] array.
 *
 * If prepend_dir is set, then we call create_pathname (which prepends
 * libdir & mapdir).  Otherwise, we assume the name given is fully
 * complete.
 * Only the editor actually cares about the writablity of this -
 * the rest of the code only cares that the file is readable.
 * when the editor goes away, the call to stat should probably be
 * replaced by an access instead (similar to the windows one, but
 * that seems to be missing the prepend_dir processing
 */

int check_path (const char *name, int prepend_dir)
{
    char buf[MAX_BUF];
#ifndef WIN32
    char *endbuf;
    struct stat statbuf;
    int mode = 0, i;
#endif

    if (prepend_dir)
        strcpy (buf, create_pathname(name));
    else
        strcpy(buf, name);
#ifdef WIN32 /* ***win32: check this sucker in windows style. */
        return(_access(buf,0));
#else

    /* old method (strchr(buf, '\0')) seemd very odd to me -
     * this method should be equivalant and is clearer.
     * Can not use strcat because we need to cycle through
     * all the names.
     */
    endbuf = buf + strlen(buf);
   
    if (stat (buf, &statbuf))
      return -1;
    if (!S_ISREG (statbuf.st_mode))
        return (-1);

    if (((statbuf.st_mode & S_IRGRP) && getegid() == statbuf.st_gid) ||
        ((statbuf.st_mode & S_IRUSR) && geteuid() == statbuf.st_uid) ||
        (statbuf.st_mode & S_IROTH))
        mode |= 4;

    if ((statbuf.st_mode & S_IWGRP && getegid() == statbuf.st_gid) ||
        (statbuf.st_mode & S_IWUSR && geteuid() == statbuf.st_uid) ||
        (statbuf.st_mode & S_IWOTH))
        mode |= 2;
    
    return (mode);
#endif
}

/*
 * Prints out debug-information about a map.
 * Dumping these at llevError doesn't seem right, but is
 * necessary to make sure the information is in fact logged.
 */

void dump_map(const mapstruct *m) {
    LOG(llevError,"Map %s status: %d.\n",m->path,m->in_memory);
    LOG(llevError,"Size: %dx%d Start: %d,%d\n",
        MAP_WIDTH(m), MAP_HEIGHT(m),
        MAP_ENTER_X(m), MAP_ENTER_Y(m));

    if(m->msg!=NULL)
        LOG(llevError,"Message:\n%s",m->msg);

    if(m->maplore!=NULL)
        LOG(llevError,"Lore:\n%s",m->maplore);

    if(m->tmpname!=NULL)
        LOG(llevError,"Tmpname: %s\n",m->tmpname);

    LOG(llevError,"Difficulty: %d\n",m->difficulty); 
    LOG(llevError,"Darkness: %d\n",m->darkness); 
}

/*
 * Prints out debug-information about all maps.
 * This basically just goes through all the maps and calls
 * dump_map on each one.
 */

void dump_all_maps(void) {
    mapstruct *m;
    for(m=first_map;m!=NULL;m=m->next) {
        dump_map(m);
  }
}

/* This rolls up wall, blocks_magic, blocks_view, etc, all into
 * one function that just returns a P_.. value (see map.h)
 * it will also do map translation for tiled maps, returning
 * new values into newmap, nx, and ny.  Any and all of those
 * values can be null, in which case if a new map is needed (returned
 * by a P_NEW_MAP value, another call to get_map_from_coord
 * is needed.  The case of not passing values is if we're just
 * checking for the existence of something on those spaces, but
 * don't expect to insert/remove anything from those spaces.
 */
int get_map_flags(mapstruct *oldmap, mapstruct **newmap, sint16 x, sint16 y, sint16 *nx, sint16 *ny)
{
    sint16 newx, newy;
    int retval=0;
    mapstruct *mp;

    if (out_of_map(oldmap, x, y)) return P_OUT_OF_MAP;
    newx = x;
    newy = y;
    mp = get_map_from_coord(oldmap, &newx, &newy);
    if (mp != oldmap)
        retval |= P_NEW_MAP;
    if (newmap) *newmap = mp;
    if (nx) *nx = newx;
    if (ny) *ny = newy;
    retval |= mp->spaces[newx + mp->width * newy].flags;

    if (retval & P_SAFE)
      retval |= P_NO_MAGIC | P_NO_CLERIC; // P_SAFE does imply these

    return retval;
}


/*
 * Returns true if the given coordinate is blocked except by the
 * object passed is not blocking.  This is used with 
 * multipart monsters - if we want to see if a 2x2 monster
 * can move 1 space to the left, we don't want its own area
 * to block it from moving there.
 * Returns TRUE if the space is blocked by something other than the
 * monster.
 * m, x, y are the target map/coordinates - needed for map tiling.
 * the coordinates & map passed in should have been updated for tiling
 * by the caller.
 */

int blocked_link(object *ob, mapstruct *m, int sx, int sy) {
    object *tmp;
    int mflags, blocked;

    /* Make sure the coordinates are valid - they should be, as caller should
     * have already checked this.
     */
    if (OUT_OF_REAL_MAP(m, sx, sy)) {
        LOG(llevError,"blocked_link: Passed map, x, y coordinates outside of map\n");
        return 1;
    }

    /* Save some cycles - instead of calling get_map_flags(), just get the value
     * directly.
     */
    mflags = m->spaces[sx + m->width * sy].flags;

    blocked = GET_MAP_MOVE_BLOCK(m, sx, sy);

    /* If space is currently not blocked by anything, no need to
     * go further.  Not true for players - all sorts of special
     * things we need to do for players.
     */
    if (ob->type != PLAYER && ! (mflags & P_IS_ALIVE) && (blocked==0)) return 0;

    /* if there isn't anytyhing alive on this space, and this space isn't
     * otherwise blocked, we can return now.  Only if there is a living
     * creature do we need to investigate if it is part of this creature
     * or another.  Likewise, only if something is blocking us do we
     * need to investigate if there is a special circumstance that would
     * let the player through (inventory checkers for example)
     */
    if (!(mflags & P_IS_ALIVE) && !OB_TYPE_MOVE_BLOCK(ob, blocked)) return 0;

    if(ob->head != NULL)
        ob=ob->head;

    /* We basically go through the stack of objects, and if there is
     * some other object that has NO_PASS or FLAG_ALIVE set, return
     * true.  If we get through the entire stack, that must mean
     * ob is blocking it, so return 0.
     */
    for(tmp = GET_MAP_OB(m,sx,sy); tmp!= NULL; tmp = tmp->above) {

        /* This must be before the checks below.  Code for inventory checkers. */
        if (tmp->type==CHECK_INV && OB_MOVE_BLOCK(ob, tmp)) {
            /* If last_sp is set, the player/monster needs an object,
             * so we check for it.  If they don't have it, they can't
             * pass through this space.
             */
            if (tmp->last_sp) {
                if (check_inv_recursive(ob,tmp)==NULL)
                    return 1;
                else
                    continue;
            } else {
                /* In this case, the player must not have the object -
                 * if they do, they can't pass through.
                 */
                if (check_inv_recursive(ob,tmp)!=NULL) /* player has object */
                    return 1;
                else
                    continue;
            }
        } /* if check_inv */
        else {
            /* Broke apart a big nasty if into several here to make
             * this more readable.  first check - if the space blocks
             * movement, can't move here.
             * second - if a monster, can't move there, unles it is a 
             * hidden dm
             */
            if (OB_MOVE_BLOCK(ob, tmp)) return 1;
            if (QUERY_FLAG(tmp,FLAG_ALIVE) && tmp->head != ob && tmp != ob && 
                tmp->type != DOOR && !(QUERY_FLAG(tmp,FLAG_WIZ) && tmp->contr->hidden))
                        return 1;
        }

    }
    return 0;
}


/*
 * Returns true if the given object can't fit in the given spot.
 * This is meant for multi space objects - for single space objecs,
 * just calling get_map_blocked and checking that against movement type
 * of object. This function goes through all the parts of the
 * multipart object and makes sure they can be inserted.
 *
 * While this doesn't call out of map, the get_map_flags does.
 *
 * This function has been used to deprecate arch_out_of_map -
 * this function also does that check, and since in most cases,
 * a call to one would follow the other, doesn't make a lot of sense to
 * have two seperate functions for this.
 *
 * This returns nonzero if this arch can not go on the space provided,
 * 0 otherwise.  the return value will contain the P_.. value
 * so the caller can know why this object can't go on the map.
 * Note that callers should not expect P_NEW_MAP to be set
 * in return codes - since the object is multispace - if
 * we did return values, what do you return if half the object
 * is one map, half on another.
 *
 * Note this used to be arch_blocked, but with new movement
 * code, we need to have actual object to check its move_type
 * against the move_block values.
 */

int ob_blocked(const object *ob,mapstruct *m,sint16 x,sint16 y) {
    archetype *tmp;
    int flag;
    mapstruct *m1;
    sint16  sx, sy;

    if(ob==NULL) {
        flag= get_map_flags(m,&m1, x,y, &sx, &sy);
        if (flag & P_OUT_OF_MAP) return P_OUT_OF_MAP;

        /* don't have object, so don't know what types would block */
        return(GET_MAP_MOVE_BLOCK(m1, sx, sy));
    }

    for(tmp=ob->arch; tmp!=NULL;tmp=tmp->more) {
        flag = get_map_flags(m, &m1, x+tmp->clone.x,y+tmp->clone.y, &sx, &sy);

        if (flag & P_OUT_OF_MAP) return P_OUT_OF_MAP;
        if (flag & P_IS_ALIVE) return P_IS_ALIVE;

        /* find_first_free_spot() calls this function.  However, often
         * ob doesn't have any move type (when used to place exits)
         * so the AND operation in OB_TYPE_MOVE_BLOCK doesn't work.
         */

        if (ob->move_type == 0 && GET_MAP_MOVE_BLOCK(m1, sx, sy) != MOVE_ALL) continue;

        /* Note it is intentional that we check ob - the movement type of the
         * head of the object should correspond for the entire object.
         */
        if (OB_TYPE_MOVE_BLOCK(ob, GET_MAP_MOVE_BLOCK(m1, sx, sy))) 
            return AB_NO_PASS;

    }
    return 0;
}

/* When the map is loaded, load_object does not actually insert objects
 * into inventory, but just links them.  What this does is go through
 * and insert them properly.
 * The object 'container' is the object that contains the inventory.
 * This is needed so that we can update the containers weight.
 */

void fix_container(object *container)
{
    object *tmp=container->inv, *next;

    container->inv=NULL;
    while (tmp!=NULL) {
        next = tmp->below;
        if (tmp->inv)
            fix_container(tmp);
        (void) insert_ob_in_ob(tmp,container);
        tmp = next;
    }
    /* sum_weight will go through and calculate what all the containers are
     * carrying.
     */
    sum_weight(container);
}

/* link_multipart_objects go through all the objects on the map looking
 * for objects whose arch says they are multipart yet according to the
 * info we have, they only have the head (as would be expected when
 * they are saved).  We do have to look for the old maps that did save
 * the more sections and not re-add sections for them.
 */

static void link_multipart_objects(mapstruct *m)
{
    int x,y;
    object *tmp, *op, *last, *above;
    archetype        *at;

    for(x=0;x<MAP_WIDTH(m);x++)
        for(y=0;y<MAP_HEIGHT(m);y++)
            for(tmp=get_map_ob(m,x,y);tmp!=NULL;tmp=above) {
                above=tmp->above;

                /* already multipart - don't do anything more */
                if (tmp->head || tmp->more) continue;

                /* If there is nothing more to this object, this for loop
                 * won't do anything.
                 */
                for (at = tmp->arch->more, last=tmp; at != NULL; at=at->more, last=op) {
                    op = arch_to_object(at);

                    /* update x,y coordinates */
                    op->x += tmp->x;
                    op->y += tmp->y;
                    op->head = tmp;
                    op->map = m;
                    last->more = op;
                    op->name = tmp->name;
                    op->title = tmp->title;
                    /* we could link all the parts onto tmp, and then just
                     * call insert_ob_in_map once, but the effect is the same,
                     * as insert_ob_in_map will call itself with each part, and
                     * the coding is simpler to just to it here with each part.
                     */
                    insert_ob_in_map(op, op->map, tmp,INS_NO_MERGE|INS_ABOVE_FLOOR_ONLY|INS_NO_WALK_ON);
                } /* for at = tmp->arch->more */
            } /* for objects on this space */
}
                    
                
/*
 * Loads (ands parses) the objects into a given map from the specified
 * file pointer.
 * mapflags is the same as we get with load_original_map
 */

void load_objects (mapstruct *m, object_thawer &fp, int mapflags) {
    int i,j;
    int unique;
    object *op, *prev=NULL,*last_more=NULL, *otmp;

    op=get_object();
    op->map = m; /* To handle buttons correctly */

    while((i = load_object (fp, op, mapflags))) {
        /* if the archetype for the object is null, means that we
         * got an invalid object.  Don't do anything with it - the game
         * or editor will not be able to do anything with it either.
         */
        if (op->arch==NULL) {
            LOG(llevDebug,"Discarding object without arch: %s\n", op->name?(const char *)op->name:"(null)");
            continue;
        }


        switch(i) {
          case LL_NORMAL:
            /* if we are loading an overlay, put the floors on the bottom */
            if ((QUERY_FLAG(op, FLAG_IS_FLOOR) ||
                 QUERY_FLAG(op, FLAG_OVERLAY_FLOOR)) && mapflags & MAP_OVERLAY)
                insert_ob_in_map(op,m,op,INS_NO_MERGE | INS_NO_WALK_ON | INS_ABOVE_FLOOR_ONLY | INS_MAP_LOAD);
            else
                insert_ob_in_map(op,m,op,INS_NO_MERGE | INS_NO_WALK_ON | INS_ON_TOP | INS_MAP_LOAD);

            if (op->inv)
                sum_weight(op);

            prev=op,last_more=op;
            break;

          case LL_MORE:
            insert_ob_in_map(op,m, op, INS_NO_MERGE | INS_NO_WALK_ON | INS_ABOVE_FLOOR_ONLY);
            op->head=prev,last_more->more=op,last_more=op;
            break;
        }
        if (mapflags & MAP_STYLE) {
            remove_from_active_list(op);
        }
        op=get_object();
        op->map = m;
    }
    for (i=0;i<m->width;i++){
            for (j=0;j<m->height;j++){
            unique =0;
            /* check for unique items, or unique squares */
            for (otmp = get_map_ob(m, i, j); otmp; otmp = otmp->above) {
                if (QUERY_FLAG(otmp, FLAG_UNIQUE) || QUERY_FLAG(otmp, FLAG_OBJ_SAVE_ON_OVL))
                    unique = 1;
                if (!(mapflags & (MAP_OVERLAY|MAP_PLAYER_UNIQUE) || unique))
                    SET_FLAG(otmp, FLAG_OBJ_ORIGINAL);
            }
        }
    }
    free_object(op);
    link_multipart_objects(m);
}

/* This saves all the objects on the map in a non destructive fashion.
 * Modified by MSW 2001-07-01 to do in a single pass - reduces code,
 * and we only save the head of multi part objects - this is needed
 * in order to do map tiling properly.
 */
void save_objects (mapstruct *m, object_freezer &fp, object_freezer &fp2, int flag) {
    int i, j = 0,unique=0;
    object *op;
    /* first pass - save one-part objects */
    for(i = 0; i < MAP_WIDTH(m); i++)
        for (j = 0; j < MAP_HEIGHT(m); j++) {
            unique=0;
            for(op = get_map_ob (m, i, j); op; op = op->above) {
                if (QUERY_FLAG(op,FLAG_IS_FLOOR) && QUERY_FLAG(op, FLAG_UNIQUE))
                    unique=1;

                if(op->type == PLAYER) {
                        LOG(llevDebug, "Player on map that is being saved\n");
                        continue;
                }

                if (op->head || op->owner)
                    continue;

                if (unique || QUERY_FLAG(op, FLAG_UNIQUE))
                    save_object (fp2, op, 3);
                else
                    if (flag == 0 ||
                        (flag == 2 && (!QUERY_FLAG(op, FLAG_OBJ_ORIGINAL) &&
                         !QUERY_FLAG(op, FLAG_UNPAID))))
                            save_object(fp, op, 3);

            } /* for this space */
        } /* for this j */
}

/*
 * Allocates, initialises, and returns a pointer to a mapstruct.
 * Modified to no longer take a path option which was not being
 * used anyways.  MSW 2001-07-01
 */

mapstruct *get_linked_map(void) {
    mapstruct *map = new mapstruct;
    mapstruct *mp;

    for(mp=first_map;mp!=NULL&&mp->next!=NULL;mp=mp->next);
    if(mp==NULL)
        first_map=map;
    else
        mp->next=map;

    map->in_memory=MAP_SWAPPED;
    /* The maps used to pick up default x and y values from the
     * map archetype.  Mimic that behaviour.
     */
    MAP_WIDTH(map)=16;
    MAP_HEIGHT(map)=16;
    MAP_RESET_TIMEOUT(map)=0;
    MAP_TIMEOUT(map)=300;
    MAP_ENTER_X(map)=0;
    MAP_ENTER_Y(map)=0;
        /*set part to -1 indicating conversion to weather map not yet done*/
        MAP_WORLDPARTX(map)=-1;
        MAP_WORLDPARTY(map)=-1;
    return map;
}

/*
 * Allocates the arrays contained in a mapstruct.
 * This basically allocates the dynamic array of spaces for the
 * map.
 */

void allocate_map(mapstruct *m) {
    m->in_memory = MAP_IN_MEMORY;
    /* Log this condition and free the storage.  We could I suppose
     * realloc, but if the caller is presuming the data will be intact,
     * that is their poor assumption.
     */
    if (m->spaces) {
        LOG(llevError,"allocate_map called with already allocated map (%s)\n", m->path);
        free(m->spaces);
    }

    m->spaces = (MapSpace *) calloc(1, MAP_WIDTH(m) * MAP_HEIGHT(m) * sizeof(MapSpace));

    if(m->spaces==NULL)
        fatal(OUT_OF_MEMORY);
}

/* Create and returns a map of the specific size.  Used
 * in random map code and the editor.
 */
mapstruct *get_empty_map(int sizex, int sizey) {
    mapstruct *m = get_linked_map();
    m->width = sizex;
    m->height = sizey;
    m->in_memory = MAP_SWAPPED;
    allocate_map(m);
    return m;
}

/* Takes a string from a map definition and outputs a pointer to the array of shopitems 
 * corresponding to that string. Memory is allocated for this, it must be freed 
 * at a later date.
 * Called by parse_map_headers below.
 */

static shopitems *parse_shop_string (const char *input_string) { 
    char *shop_string, *p, *q, *next_semicolon, *next_colon; 
    shopitems *items=NULL;
    int i=0, number_of_entries=0;
    const typedata *current_type; 

    shop_string=strdup_local(input_string); 
    p=shop_string; 
    /* first we'll count the entries, we'll need that for allocating the array shortly */
    while (p) {
        p=strchr(p, ';');
        number_of_entries++;
        if (p) p++;
    }
    p=shop_string;
    strip_endline(p);
    items=(shopitems *) CALLOC(number_of_entries+1, sizeof(shopitems));
    memset(items, 0, (sizeof(shopitems) * number_of_entries+1));
    for (i=0; i<number_of_entries; i++) {
        if (!p) {
            LOG(llevError, "parse_shop_string: I seem to have run out of string, that shouldn't happen.\n");
            break; 
        }
        next_semicolon=strchr(p, ';');
        next_colon=strchr(p, ':');
        /* if there is a stregth specified, figure out what it is, we'll need it soon. */
        if (next_colon &&( !next_semicolon || next_colon<next_semicolon)) 
            items[i].strength=atoi(strchr(p,':')+1);
        
        if (isdigit(*p) || *p=='*') {
            items[i].typenum = atoi(p); /* atoi returns 0 when we have an asterisk */
            current_type=get_typedata(items[i].typenum);
            if (current_type) {
                items[i].name=current_type->name;
                items[i].name_pl=current_type->name_pl;
            } 
        }
        else { /*we have a named type, let's figure out what it is */ 
            q=strpbrk(p,";:");
            if (q) *q='\0';
        
            current_type=get_typedata_by_name(p);
            if (current_type) {
                items[i].name=current_type->name;
                items[i].typenum=current_type->number;
                items[i].name_pl=current_type->name_pl;
            }
            else { /* oh uh, something's wrong, let's free up this one, and try
                    * the next entry while we're at it, better print a warning 
                    */ 
                LOG(llevError, "invalid type %s defined in shopitems in string %s\n",
                    p, input_string);
            }
        }
        items[i].index=number_of_entries;
        if (next_semicolon) p=++next_semicolon;
        else p=NULL;
    }
    free(shop_string); 
    return items; 
}

/* opposite of parse string, this puts the string that was originally fed in to
 * the map (or something equivilent) into output_string. */
static void print_shop_string(mapstruct *m, char *output_string) {
    int i;
    char tmp[MAX_BUF];
    strcpy(output_string, "");
    for (i=0; i< m->shopitems[0].index; i++) {
        if (m->shopitems[i].typenum) {
            if (m->shopitems[i].strength) {
                sprintf(tmp, "%s:%d;", m->shopitems[i].name, m->shopitems[i].strength);
            }
            else sprintf(tmp, "%s;", m->shopitems[i].name);
        }
        else {
            if (m->shopitems[i].strength) {
                sprintf(tmp, "*:%d;", m->shopitems[i].strength);
            }
            else sprintf(tmp, "*");
        }
        strcat(output_string, tmp);
    }
}

/* This loads the header information of the map.  The header
 * contains things like difficulty, size, timeout, etc.
 * this used to be stored in the map object, but with the
 * addition of tiling, fields beyond that easily named in an
 * object structure were needed, so it just made sense to
 * put all the stuff in the map object so that names actually make
 * sense.
 * This could be done in lex (like the object loader), but I think
 * currently, there are few enough fields this is not a big deal.
 * MSW 2001-07-01
 * return 0 on success, 1 on failure.
 */

static int load_map_header(object_thawer &fp, mapstruct *m)
{
    char buf[HUGE_BUF], msgbuf[HUGE_BUF], maplorebuf[HUGE_BUF], *key=NULL, *value, *end;
    int msgpos=0;
    int maplorepos=0;

    while (fgets(buf, HUGE_BUF-1, fp)!=NULL) {
        buf[HUGE_BUF-1] = 0;
        key = buf;
        while (isspace(*key)) key++;
        if (*key == 0) continue;    /* empty line */
        value = strchr(key, ' ');
        if (!value) {
            end = strchr(key, '\n');
            if (end != NULL) {
                *end = 0;
            }
        } else {
            *value = 0;
            value++;
            end = strchr(value, '\n');
            while (isspace(*value)) {
                value++;
                if (*value == '\0' || value == end) {
                    /* Nothing but spaces. */
                    value = NULL;
                    break;
                }
            }
        }

        if (!end) {
            LOG(llevError, "Error loading map header - did not find a newline - perhaps file is truncated?  Buf=%s\n",
                buf);
            return 1;
        }

        /* key is the field name, value is what it should be set
         * to.  We've already done the work to null terminate key,
         * and strip off any leading spaces for both of these.
         * We have not touched the newline at the end of the line -
         * these are needed for some values.  the end pointer 
         * points to the first of the newlines.
         * value could be NULL!  It would be easy enough to just point
         * this to "" to prevent cores, but that would let more errors slide
         * through.
         *
         * First check for entries that do not use the value parameter, then
         * validate that value is given and check for the remaining entries
         * that use the parameter.
         */

        if (!strcmp(key,"msg")) {
            while (fgets(buf, HUGE_BUF-1, fp)!=NULL) {
                if (!strcmp(buf,"endmsg\n")) break;
                else {
                    /* slightly more efficient than strcat */
                    strcpy(msgbuf+msgpos, buf);
                    msgpos += strlen(buf);
                }
            }
            /* There are lots of maps that have empty messages (eg, msg/endmsg
             * with nothing between).  There is no reason in those cases to
             * keep the empty message.  Also, msgbuf contains garbage data
             * when msgpos is zero, so copying it results in crashes
             */
            if (msgpos != 0)
                m->msg = strdup_local(msgbuf);
        }
        else if (!strcmp(key,"maplore")) {
            while (fgets(buf, HUGE_BUF-1, fp)!=NULL) {
                if (!strcmp(buf,"endmaplore\n")) break;
                else {
                    /* slightly more efficient than strcat */
                    strcpy(maplorebuf+maplorepos, buf);
                    maplorepos += strlen(buf);
                }
            }
            if (maplorepos != 0)
                m->maplore = strdup_local(maplorebuf);
        }
        else if (!strcmp(key,"end")) {
            break;
        }
        else if (value == NULL) {
            LOG(llevError, "Got '%s' line without parameter in map header\n", key);
        }
        else if (!strcmp(key, "arch")) {
            /* This is an oddity, but not something we care about much. */
            if (strcmp(value,"map\n")) 
                LOG(llevError,"loading map and got a non 'arch map' line(%s %s)?\n",key,value);
        }
        else if (!strcmp(key,"name")) {
            *end=0;
            m->name = strdup_local(value);
        }
        /* first strcmp value on these are old names supported
         * for compatibility reasons.  The new values (second) are
         * what really should be used.
         */
        else if (!strcmp(key,"oid")) {
            fp.get (m, atoi(value));
        } else if (!strcmp(key, "attach")) {
            m->attach = value;
        } else if (!strcmp(key,"hp") || !strcmp(key, "enter_x")) {
            m->enter_x = atoi(value);
        } else if (!strcmp(key,"sp") || !strcmp(key, "enter_y")) {
            m->enter_y = atoi(value);
        } else if (!strcmp(key,"x") || !strcmp(key, "width")) {
            m->width = atoi(value);
        } else if (!strcmp(key,"y") || !strcmp(key, "height")) {
            m->height = atoi(value);
        } else if (!strcmp(key,"weight") || !strcmp(key, "reset_timeout")) {
            m->reset_timeout = atoi(value);
        } else if (!strcmp(key,"value") || !strcmp(key, "swap_time")) {
            m->timeout = atoi(value);
        } else if (!strcmp(key,"level") || !strcmp(key, "difficulty")) {
            m->difficulty = atoi(value);
        } else if (!strcmp(key,"invisible") || !strcmp(key, "darkness")) {
            m->darkness = atoi(value);
        } else if (!strcmp(key,"stand_still") || !strcmp(key, "fixed_resettime")) {
            m->fixed_resettime = atoi(value);
        } else if (!strcmp(key,"unique")) {
            m->unique = atoi(value);
        } else if (!strcmp(key,"template")) {
            m->templatemap = atoi(value);
        } else if (!strcmp(key,"region")) {
            m->region = get_region_by_name(value);
        } else if (!strcmp(key,"shopitems")) {
            *end=0;
            m->shopitems = parse_shop_string(value);
        } else if (!strcmp(key,"shopgreed")) {
            m->shopgreed = atof(value);
        } else if (!strcmp(key,"shopmin")) {
            m->shopmin = atol(value);
        } else if (!strcmp(key,"shopmax")) {
            m->shopmax = atol(value);
        } else if (!strcmp(key,"shoprace")) {
            *end=0;
            m->shoprace = strdup_local(value);
        } else if (!strcmp(key,"outdoor")) {
            m->outdoor = atoi(value);
        } else if (!strcmp(key, "temp")) {
            m->temp = atoi(value);
        } else if (!strcmp(key, "pressure")) {
            m->pressure = atoi(value);
        } else if (!strcmp(key, "humid")) {
            m->humid = atoi(value);
        } else if (!strcmp(key, "windspeed")) {
            m->windspeed = atoi(value);
        } else if (!strcmp(key, "winddir")) {
            m->winddir = atoi(value);
        } else if (!strcmp(key, "sky")) {
            m->sky = atoi(value);
        } else if (!strcmp(key, "nosmooth")) {
            m->nosmooth = atoi(value);
        }
        else if (!strncmp(key,"tile_path_", 10)) {
            int tile=atoi(key+10);

            if (tile<1 || tile>4) {
                LOG(llevError,"load_map_header: tile location %d out of bounds (%s)\n",
                    tile, m->path);
            } else {
                char *path;

                *end = 0;

                if (m->tile_path[tile-1]) {
                    LOG(llevError,"load_map_header: tile location %d duplicated (%s)\n",
                        tile, m->path);
                    free(m->tile_path[tile-1]);
                    m->tile_path[tile-1] = NULL;
                }

                if (check_path(value, 1) != -1) {
                    /* The unadorned path works. */
                    path = value;
                } else {
                    /* Try again; it could be a relative exit. */

                    path = path_combine_and_normalize(m->path, value);

                    if (check_path(path, 1) == -1) {
                        LOG(llevError, "get_map_header: Bad tile path %s %s\n", m->path, value);
                        path = NULL;
                    }
                }

                if (editor) {
                    /* Use the value as in the file. */
                    m->tile_path[tile-1] = strdup_local(value);
                } else if (path != NULL) {
                    /* Use the normalized value. */
                    m->tile_path[tile-1] = strdup_local(path);
                }
            } /* end if tile direction (in)valid */
        }
        else {
            LOG(llevError,"Got unknown value in map header: %s %s\n", key, value);
        }
    }
    if (!key || strcmp(key,"end")) {
        LOG(llevError,"Got premature eof on map header!\n");
        abort();//D
        return 1;
    }
    return 0;
}

/*
 * Opens the file "filename" and reads information about the map
 * from the given file, and stores it in a newly allocated
 * mapstruct.  A pointer to this structure is returned, or NULL on failure.
 * flags correspond to those in map.h.  Main ones used are
 * MAP_PLAYER_UNIQUE, in which case we don't do any name changes, and
 * MAP_BLOCK, in which case we block on this load.  This happens in all
 *   cases, no matter if this flag is set or not.
 * MAP_STYLE: style map - don't add active objects, don't add to server
 *                managed map list.
 */

mapstruct *load_original_map(const char *filename, int flags) {
    mapstruct *m;
    char pathname[MAX_BUF];
    
    if (flags & MAP_PLAYER_UNIQUE) 
        strcpy(pathname, filename);
    else if (flags & MAP_OVERLAY)
        strcpy(pathname, create_overlay_pathname(filename));
    else
        strcpy(pathname, create_pathname(filename));

    LOG(llevDebug, "load_original_map(%x): %s (%s)\n", flags, filename, pathname);

    object_thawer thawer (pathname);

    if (!thawer)
      return 0;

    m = get_linked_map();

    strcpy (m->path, filename);
    if (load_map_header(thawer, m)) {
        LOG(llevError,"Error loading map header for %s, flags=%d\n",
            filename, flags);
        delete_map(m);
        return NULL;
    }

    allocate_map(m);

    m->in_memory=MAP_LOADING;
    load_objects (m, thawer, flags & (MAP_BLOCK|MAP_STYLE));

    m->in_memory=MAP_IN_MEMORY;
    if (!MAP_DIFFICULTY(m)) 
        MAP_DIFFICULTY(m)=calculate_difficulty(m);
    set_map_reset_time(m);
    m->instantiate ();
    return (m);
}

/*
 * Loads a map, which has been loaded earlier, from file.
 * Return the map object we load into (this can change from the passed
 * option if we can't find the original map)
 */

static mapstruct *load_temporary_map(mapstruct *m) {
    int comp;
    char buf[MAX_BUF];
    
    if (!m->tmpname) {
        LOG(llevError, "No temporary filename for map %s\n", m->path);
        strcpy(buf, m->path);
        delete_map(m);
        m = load_original_map(buf, 0);
        if(m==NULL) return NULL;
        fix_auto_apply(m); /* Chests which open as default */
        return m;
    }

    object_thawer thawer (m->tmpname);

    if (!thawer)
      {
        strcpy (buf, m->path);
        delete_map (m);
        m = load_original_map (buf, 0);
        if (!m) return NULL;
        fix_auto_apply (m); /* Chests which open as default */
        return m;
      }

    if (load_map_header(thawer, m)) {
        LOG(llevError,"Error loading map header for %s (%s)\n",
            m->path, m->tmpname);
        delete_map(m);
        m = load_original_map(m->path, 0);
        return NULL;
    }
    allocate_map(m);

    m->in_memory=MAP_LOADING;
    load_objects (m, thawer, 0);

    m->in_memory=MAP_IN_MEMORY;
    INVOKE_MAP (SWAPIN, m);
    return m;
}

/*
 * Loads a map, which has been loaded earlier, from file.
 * Return the map object we load into (this can change from the passed
 * option if we can't find the original map)
 */

mapstruct *load_overlay_map(const char *filename, mapstruct *m) {
    char pathname[MAX_BUF];

    strcpy(pathname, create_overlay_pathname(filename));

    object_thawer thawer (pathname);

    if (!thawer)
      return m;
    
    if (load_map_header(thawer, m)) {
        LOG(llevError,"Error loading map header for overlay %s (%s)\n",
            m->path, pathname);
        delete_map(m);
        m = load_original_map(m->path, 0);
        return NULL;
    }
    /*allocate_map(m);*/

    m->in_memory=MAP_LOADING;
    load_objects (m, thawer, MAP_OVERLAY);

    m->in_memory=MAP_IN_MEMORY;
    return m;
}

/******************************************************************************
 * This is the start of unique map handling code
 *****************************************************************************/

/* This goes through map 'm' and removed any unique items on the map. */
static void delete_unique_items(mapstruct *m)
{
    int i,j,unique;
    object *op, *next;

    for(i=0; i<MAP_WIDTH(m); i++)
        for(j=0; j<MAP_HEIGHT(m); j++) {
            unique=0;
            for (op=get_map_ob(m, i, j); op; op=next) {
                next = op->above;
                if (QUERY_FLAG(op, FLAG_IS_FLOOR) && QUERY_FLAG(op, FLAG_UNIQUE))
                    unique=1;
                if(op->head == NULL && (QUERY_FLAG(op, FLAG_UNIQUE) || unique)) {
                    clean_object(op);
                    if (QUERY_FLAG(op, FLAG_IS_LINKED))
                        remove_button_link(op);
                    remove_ob(op);
                    free_object(op);
                }
            }
        }
}


/*
 * Loads unique objects from file(s) into the map which is in memory
 * m is the map to load unique items into.
 */
static void load_unique_objects(mapstruct *m) {
    int count;
    char firstname[MAX_BUF];

    for (count=0; count<10; count++) {
        sprintf(firstname, "%s.v%02d", create_items_path(m->path), count);
        if (!access(firstname, R_OK)) break;
    }
    /* If we get here, we did not find any map */
    if (count==10) return;

    object_thawer thawer (firstname);

    if (!thawer)
      return;

    m->in_memory=MAP_LOADING;
    if (m->tmpname == NULL)    /* if we have loaded unique items from */
      delete_unique_items(m); /* original map before, don't duplicate them */
    load_objects (m, thawer, 0);

    m->in_memory=MAP_IN_MEMORY;
}


/*
 * Saves a map to file.  If flag is set, it is saved into the same
 * file it was (originally) loaded from.  Otherwise a temporary
 * filename will be genarated, and the file will be stored there.
 * The temporary filename will be stored in the mapstructure.
 * If the map is unique, we also save to the filename in the map
 * (this should have been updated when first loaded)
 */

int
new_save_map (mapstruct * m, int flag)
{
  char filename[MAX_BUF], buf[MAX_BUF], buf_s[MAX_BUF], shop[MAX_BUF];
  int i;

  if (flag && !*m->path)
    {
      LOG (llevError, "Tried to save map without path.\n");
      return -1;
    }

  if (flag || (m->unique) || (m->templatemap))
    {
      if (!m->unique && !m->templatemap)
        {                        /* flag is set */
          if (flag == 2)
            strcpy (filename, create_overlay_pathname (m->path));
          else
            strcpy (filename, create_pathname (m->path));
        }
      else
        strcpy (filename, m->path);

      make_path_to_file (filename);
    }
  else
    {
      if (!m->tmpname)
        m->tmpname = tempnam_local (settings.tmpdir, NULL);

      strcpy (filename, m->tmpname);
    }

  LOG (llevDebug, "Saving map %s to %s\n", m->path, filename);
  m->in_memory = MAP_SAVING;

  object_freezer freezer;

  /* legacy */
  fprintf (freezer, "arch map\n");
  if (m->name)
    fprintf (freezer, "name %s\n", m->name);
  if (!flag)
    fprintf (freezer, "swap_time %d\n", m->swap_time);
  if (m->reset_timeout)
    fprintf (freezer, "reset_timeout %d\n", m->reset_timeout);
  if (m->fixed_resettime)
    fprintf (freezer, "fixed_resettime %d\n", m->fixed_resettime);
  /* we unfortunately have no idea if this is a value the creator set
   * or a difficulty value we generated when the map was first loaded
   */
  if (m->difficulty)
    fprintf (freezer, "difficulty %d\n", m->difficulty);
  if (m->region)
    fprintf (freezer, "region %s\n", m->region->name);
  if (m->shopitems)
    {
      print_shop_string (m, shop);
      fprintf (freezer, "shopitems %s\n", shop);
    }
  if (m->shopgreed)
    fprintf (freezer, "shopgreed %f\n", m->shopgreed);
#ifndef WIN32
  if (m->shopmin)
    fprintf (freezer, "shopmin %llu\n", m->shopmin);
  if (m->shopmax)
    fprintf (freezer, "shopmax %llu\n", m->shopmax);
#else
  if (m->shopmin)
    fprintf (freezer, "shopmin %I64u\n", m->shopmin);
  if (m->shopmax)
    fprintf (freezer, "shopmax %I64u\n", m->shopmax);
#endif
  if (m->shoprace)
    fprintf (freezer, "shoprace %s\n", m->shoprace);
  if (m->darkness)
    fprintf (freezer, "darkness %d\n", m->darkness);
  if (m->width)
    fprintf (freezer, "width %d\n", m->width);
  if (m->height)
    fprintf (freezer, "height %d\n", m->height);
  if (m->enter_x)
    fprintf (freezer, "enter_x %d\n", m->enter_x);
  if (m->enter_y)
    fprintf (freezer, "enter_y %d\n", m->enter_y);
  if (m->msg)
    fprintf (freezer, "msg\n%sendmsg\n", m->msg);
  if (m->maplore)
    fprintf (freezer, "maplore\n%sendmaplore\n", m->maplore);
  if (m->unique)
    fprintf (freezer, "unique %d\n", m->unique);
  if (m->templatemap)
    fprintf (freezer, "template %d\n", m->templatemap);
  if (m->outdoor)
    fprintf (freezer, "outdoor %d\n", m->outdoor);
  if (m->temp)
    fprintf (freezer, "temp %d\n", m->temp);
  if (m->pressure)
    fprintf (freezer, "pressure %d\n", m->pressure);
  if (m->humid)
    fprintf (freezer, "humid %d\n", m->humid);
  if (m->windspeed)
    fprintf (freezer, "windspeed %d\n", m->windspeed);
  if (m->winddir)
    fprintf (freezer, "winddir %d\n", m->winddir);
  if (m->sky)
    fprintf (freezer, "sky %d\n", m->sky);
  if (m->nosmooth)
    fprintf (freezer, "nosmooth %d\n", m->nosmooth);

  /* Save any tiling information, except on overlays */
  if (flag != 2)
    for (i = 0; i < 4; i++)
      if (m->tile_path[i])
        fprintf (freezer, "tile_path_%d %s\n", i + 1, m->tile_path[i]);

  freezer.put (m);
  fprintf (freezer, "end\n");

  /* In the game save unique items in the different file, but
   * in the editor save them to the normal map file.
   * If unique map, save files in the proper destination (set by
   * player)
   */
  if ((flag == 0 || flag == 2) && !m->unique && !m->templatemap)
    {
      object_freezer unique;

      if (flag == 2)
        save_objects (m, freezer, unique, 2);
      else
        save_objects (m, freezer, unique, 0);

      sprintf (buf, "%s.v00", create_items_path (m->path));

      unique.save (buf);
    }
  else
    {                                /* save same file when not playing, like in editor */
      save_objects (m, freezer, freezer, 0);
    }

  freezer.save (filename);

  return 0;
}


/*
 * Remove and free all objects in the inventory of the given object.
 * object.c ?
 */

void clean_object(object *op)
{
    object *tmp, *next;

    for(tmp = op->inv; tmp; tmp = next)
    {
        next = tmp->below;
        clean_object(tmp);
        if (QUERY_FLAG(tmp, FLAG_IS_LINKED))
            remove_button_link(tmp);
        remove_ob(tmp);
        free_object(tmp);
    }
}

/*
 * Remove and free all objects in the given map.
 */

void free_all_objects(mapstruct *m) {
    int i,j;
    object *op;

    for(i=0;i<MAP_WIDTH(m);i++)
        for(j=0;j<MAP_HEIGHT(m);j++) {
            object *previous_obj=NULL;
            while((op=GET_MAP_OB(m,i,j))!=NULL) {
                if (op==previous_obj) {
                    LOG(llevDebug, "free_all_objects: Link error, bailing out.\n");
                    break;
                }
                previous_obj=op;
                if(op->head!=NULL)
                    op = op->head;

                /* If the map isn't in memory, free_object will remove and
                 * free objects in op's inventory.  So let it do the job.
                 */
                if (m->in_memory==MAP_IN_MEMORY)
                    clean_object(op);
                remove_ob(op);
                free_object(op);
            }
        }
}

/*
 * Frees everything allocated by the given mapstructure.
 * don't free tmpname - our caller is left to do that
 */

void free_map(mapstruct *m,int flag) {
    int i;

    if (!m->in_memory) {
        LOG(llevError,"Trying to free freed map.\n");
        return;
    }
    if (flag && m->spaces) free_all_objects(m);
    if (m->name) FREE_AND_CLEAR(m->name);
    if (m->spaces) FREE_AND_CLEAR(m->spaces);
    if (m->msg) FREE_AND_CLEAR(m->msg);
    if (m->maplore) FREE_AND_CLEAR(m->maplore);
    if (m->shopitems) FREE_AND_CLEAR(m->shopitems);
    if (m->shoprace) FREE_AND_CLEAR(m->shoprace);
    if (m->buttons)
        free_objectlinkpt(m->buttons);
    m->buttons = NULL;
    for (i=0; i<4; i++) {
        if (m->tile_path[i]) FREE_AND_CLEAR(m->tile_path[i]);
        m->tile_map[i] = NULL;
    }
    m->in_memory = MAP_SWAPPED;
}

/*
 * function: vanish mapstruct
 * m       : pointer to mapstruct, if NULL no action
 * this deletes all the data on the map (freeing pointers)
 * and then removes this map from the global linked list of maps.
 */

void delete_map(mapstruct *m) {
    mapstruct *tmp, *last;
    int i;

    if (!m)
      return;

    m->clear ();

    if (m->in_memory == MAP_IN_MEMORY) {
        /* change to MAP_SAVING, even though we are not,
         * so that remove_ob doesn't do as much work.
         */
        m->in_memory = MAP_SAVING;
        free_map (m, 1);
    }
    /* move this out of free_map, since tmpname can still be needed if
     * the map is swapped out.
     */
    if (m->tmpname) {
        free(m->tmpname);
        m->tmpname=NULL;
    }
    last = NULL;
    /* We need to look through all the maps and see if any maps
     * are pointing at this one for tiling information.  Since
     * tiling can be assymetric, we just can not look to see which
     * maps this map tiles with and clears those.
     */
    for (tmp = first_map; tmp != NULL; tmp = tmp->next) {
        if (tmp->next == m) last = tmp;

        /* This should hopefully get unrolled on a decent compiler */
        for (i=0; i<4; i++)
            if (tmp->tile_map[i] == m) tmp->tile_map[i]=NULL;
    }

    /* If last is null, then this should be the first map in the list */
    if (!last) {
        if (m == first_map)
            first_map = m->next;
        else
            /* m->path is a static char, so should hopefully still have
             * some useful data in it.
             */
            LOG(llevError,"delete_map: Unable to find map %s in list\n",
                m->path);
    }
    else
        last->next = m->next;

    delete m;
}


/*
 * Makes sure the given map is loaded and swapped in.
 * name is path name of the map.
 * flags meaning:
 * 0x1 (MAP_FLUSH): flush the map - always load from the map directory,
 *   and don't do unique items or the like.
 * 0x2 (MAP_PLAYER_UNIQUE) - this is a unique map for each player.
 *   dont do any more name translation on it.
 *
 * Returns a pointer to the given map.
 */

mapstruct *ready_map_name(const char *name, int flags) {
    mapstruct *m;

    if (!name)
       return (NULL);

    /* Have we been at this level before? */
    m = has_been_loaded (name);

    /* Map is good to go, so just return it */
    if (m && (m->in_memory == MAP_LOADING || m->in_memory == MAP_IN_MEMORY)) {
        return m;
    }

    /* unique maps always get loaded from their original location, and never
     * a temp location.  Likewise, if map_flush is set, or we have never loaded
     * this map, load it now.  I removed the reset checking from here -
     * it seems the probability of a player trying to enter a map that should
     * reset but hasn't yet is quite low, and removing that makes this function
     * a bit cleaner (and players probably shouldn't rely on exact timing for
     * resets in any case - if they really care, they should use the 'maps command.
     */
    if ((flags & (MAP_FLUSH|MAP_PLAYER_UNIQUE)) || !m) {

        /* first visit or time to reset */
        if (m) {
            clean_tmp_map(m);        /* Doesn't make much difference */
            delete_map(m);
        }

        /* create and load a map */
        if (flags & MAP_PLAYER_UNIQUE)
            LOG(llevDebug, "Trying to load map %s.\n", name);
        else
            LOG(llevDebug, "Trying to load map %s.\n", create_pathname(name));

        //0.427459955215454 /var/crossfire/players/Saladon/_scorn_apartment_apartments
        //0.414906024932861
        //0.427063941955566
        eval_pv ("$x = Event::time", 1);//D
        if (!(m = load_original_map(name, (flags & MAP_PLAYER_UNIQUE))))
            return (NULL);
        eval_pv ("warn \"LOAD \", Event::time - $x", 1);//D

        fix_auto_apply(m); /* Chests which open as default */

        /* If a player unique map, no extra unique object file to load.
         * if from the editor, likewise.
         */
        if (! (flags & (MAP_FLUSH|MAP_PLAYER_UNIQUE))) 
            load_unique_objects(m);

        if (! (flags & (MAP_FLUSH|MAP_PLAYER_UNIQUE|MAP_OVERLAY))) {
            m=load_overlay_map(name, m);
            if (m==NULL)
                return NULL;
        }

        if (flags & MAP_PLAYER_UNIQUE)
          INVOKE_MAP (SWAPIN, m);

    } else {
        /* If in this loop, we found a temporary map, so load it up. */

        m=load_temporary_map (m);
        if(m==NULL) return NULL;
        load_unique_objects(m);

        clean_tmp_map(m);
        m->in_memory = MAP_IN_MEMORY;
        /* tempnam() on sun systems (probably others) uses malloc
         * to allocated space for the string.  Free it here.
         * In some cases, load_temporary_map above won't find the
         * temporary map, and so has reloaded a new map.  If that
         * is the case, tmpname is now null
         */
        if (m->tmpname) free(m->tmpname);
        m->tmpname = NULL;
        /* It's going to be saved anew anyway */
    } 

    /* Below here is stuff common to both first time loaded maps and
     * temp maps.
     */

    decay_objects(m); /* start the decay */
    /* In case other objects press some buttons down */
    update_buttons(m);
    if (m->outdoor)
            set_darkness_map(m);
    /* run the weather over this map */
    weather_effect(name);
    return m;
}


/*
 * This routine is supposed to find out the difficulty of the map.
 * difficulty does not have a lot to do with character level,
 * but does have a lot to do with treasure on the map.
 *
 * Difficulty can now be set by the map creature.  If the value stored
 * in the map is zero, then use this routine.  Maps should really
 * have a difficulty set than using this function - human calculation
 * is much better than this functions guesswork.
 */

int calculate_difficulty(mapstruct *m) {
  object *op;
  archetype *at;
  int x, y, i, diff;
  long monster_cnt = 0;
  double avgexp = 0;
  sint64 total_exp = 0;

  if (MAP_DIFFICULTY (m))
    {
      LOG(llevDebug, "Using stored map difficulty: %d\n", MAP_DIFFICULTY (m));
      return MAP_DIFFICULTY (m);
    }

  for(x = 0; x < MAP_WIDTH(m); x++)
    for(y = 0; y < MAP_HEIGHT(m); y++)
      for(op = get_map_ob(m, x, y); op != NULL; op = op->above)
        {
          if(QUERY_FLAG (op, FLAG_MONSTER))
            {
              total_exp += op->stats.exp;
              monster_cnt++;
            }

          if(QUERY_FLAG (op, FLAG_GENERATOR))
            {
              total_exp += op->stats.exp;
              at = type_to_archetype(GENERATE_TYPE (op));

              if(at != NULL)
                total_exp += at->clone.stats.exp * 8;

              monster_cnt++;
            }
        }

  avgexp = (double) total_exp / monster_cnt;

  for (i = 1; i <= settings.max_level; i++)
    {
      if ((level_exp (i, 1) - level_exp (i - 1, 1)) > (100 * avgexp))
        {
          /* LOG(llevDebug, "Calculated difficulty for map: %s: %d\n", m->name, i); */
          return i;
        }
    }

  return 1;
}

void clean_tmp_map(mapstruct *m) {
    if(m->tmpname == NULL)
        return;
  INVOKE_MAP (CLEAN, m);
  (void) unlink(m->tmpname);
}

void free_all_maps(void)
{
    int real_maps=0;

    while (first_map) {
        /* I think some of the callers above before it gets here set this to be 
         * saving, but we still want to free this data
         */
        if (first_map->in_memory == MAP_SAVING) first_map->in_memory = MAP_IN_MEMORY;
        delete_map(first_map);
        real_maps++;
    }
    LOG(llevDebug,"free_all_maps: Freed %d maps\n", real_maps);
}

/* change_map_light() - used to change map light level (darkness)
 * up or down. Returns true if successful.   It should now be
 * possible to change a value by more than 1.
 * Move this from los.c to map.c since this is more related
 * to maps than los.
 * postive values make it darker, negative make it brighter
 */
 
int change_map_light(mapstruct *m, int change) {
    int new_level = m->darkness + change;
 
    /* Nothing to do */
    if(!change || (new_level <= 0 && m->darkness == 0) || 
       (new_level >= MAX_DARKNESS && m->darkness >=MAX_DARKNESS)) {
        return 0;
    }

    /* inform all players on the map */
    if (change>0) 
            new_info_map(NDI_BLACK|NDI_UNIQUE, m,"It becomes darker.");
    else
            new_info_map(NDI_BLACK|NDI_UNIQUE, m,"It becomes brighter.");

    /* Do extra checking.  since m->darkness is a unsigned value,
     * we need to be extra careful about negative values.
     * In general, the checks below are only needed if change
     * is not +/-1
     */
    if (new_level < 0) m->darkness = 0;
    else if (new_level >=MAX_DARKNESS) m->darkness = MAX_DARKNESS;
    else m->darkness=new_level;

    /* All clients need to get re-updated for the change */
    update_all_map_los(m);
    return 1;
}


/* 
 * This function updates various attributes about a specific space
 * on the map (what it looks like, whether it blocks magic,
 * has a living creatures, prevents people from passing
 * through, etc)
 */
void update_position (mapstruct *m, int x, int y) {
    object *tmp, *last = NULL;
    uint8 flags = 0, oldflags, light=0, anywhere=0;
    New_Face *top,*floor, *middle;
    object *top_obj, *floor_obj, *middle_obj;
    MoveType        move_block=0, move_slow=0, move_on=0, move_off=0, move_allow=0;

    oldflags = GET_MAP_FLAGS(m,x,y);
    if (!(oldflags & P_NEED_UPDATE)) {
        LOG(llevDebug,"update_position called with P_NEED_UPDATE not set: %s (%d, %d)\n",
            m->path, x, y);
        return;
    }

    middle=blank_face;
    top=blank_face;
    floor=blank_face;

    middle_obj = NULL;
    top_obj = NULL;
    floor_obj = NULL;

    for (tmp = get_map_ob (m, x, y); tmp; last = tmp, tmp = tmp->above) {

        /* This could be made additive I guess (two lights better than
         * one).  But if so, it shouldn't be a simple additive - 2
         * light bulbs do not illuminate twice as far as once since
         * it is a disapation factor that is squared (or is it cubed?)
         */
        if (tmp->glow_radius > light) light = tmp->glow_radius;

        /* This call is needed in order to update objects the player
         * is standing in that have animations (ie, grass, fire, etc).
         * However, it also causes the look window to be re-drawn
         * 3 times each time the player moves, because many of the
         * functions the move_player calls eventualy call this.
         *
         * Always put the player down for drawing.
         */
        if (!tmp->invisible) {
            if ((tmp->type==PLAYER || QUERY_FLAG(tmp, FLAG_MONSTER))) {
                top = tmp->face;
                top_obj = tmp;
            }
            else if (QUERY_FLAG(tmp,FLAG_IS_FLOOR)) {
                /* If we got a floor, that means middle and top were below it,
                * so should not be visible, so we clear them.
                */
                middle=blank_face;
                top=blank_face;
                floor = tmp->face;
                floor_obj = tmp;
            }
            /* Flag anywhere have high priority */
            else if (QUERY_FLAG(tmp, FLAG_SEE_ANYWHERE)) {
                middle = tmp->face;

                middle_obj = tmp;
                anywhere =1;
            }
            /* Find the highest visible face around.  If equal
             * visibilities, we still want the one nearer to the
             * top
             */
            else if (middle == blank_face || (tmp->face->visibility > middle->visibility && !anywhere)) {
                    middle = tmp->face;
                middle_obj = tmp;
            }
        }
        if (tmp==tmp->above) {
            LOG(llevError, "Error in structure of map\n");
            exit (-1);
        }
      
        move_slow |= tmp->move_slow;
        move_block |= tmp->move_block;
        move_on |= tmp->move_on;
        move_off |= tmp->move_off;
        move_allow |= tmp->move_allow;

        if (QUERY_FLAG(tmp,FLAG_ALIVE))
            flags |= P_IS_ALIVE;
        if (QUERY_FLAG(tmp,FLAG_NO_MAGIC))
            flags |= P_NO_MAGIC;
        if (QUERY_FLAG(tmp,FLAG_DAMNED))
            flags |= P_NO_CLERIC;
        if (tmp->type == SAFE_GROUND)
            flags |= P_SAFE | P_NO_CLERIC | P_NO_MAGIC;

        if (QUERY_FLAG(tmp,FLAG_BLOCKSVIEW))
            flags |= P_BLOCKSVIEW;
    } /* for stack of objects */

    /* we don't want to rely on this function to have accurate flags, but
     * since we're already doing the work, we calculate them here.
     * if they don't match, logic is broken someplace.
     */
    if (((oldflags & ~(P_NEED_UPDATE|P_NO_ERROR)) != flags) &&
        (!(oldflags & P_NO_ERROR))) {
        LOG(llevDebug,"update_position: updated flags do not match old flags: %s (old=%d,new=%d) %x != %x\n",
            m->path, x, y,
            (oldflags & ~P_NEED_UPDATE), flags);
    }
    SET_MAP_FLAGS(m, x, y, flags);
    SET_MAP_MOVE_BLOCK(m, x, y, move_block & ~move_allow);
    SET_MAP_MOVE_ON(m, x, y, move_on);
    SET_MAP_MOVE_OFF(m, x, y, move_off);
    SET_MAP_MOVE_SLOW(m, x, y, move_slow);

    /* At this point, we have a floor face (if there is a floor),
     * and the floor is set - we are not going to touch it at
     * this point.
     * middle contains the highest visibility face. 
     * top contains a player/monster face, if there is one.
     *
     * We now need to fill in top.face and/or middle.face.
     */

    /* If the top face also happens to be high visibility, re-do our
     * middle face.  This should not happen, as we already have the
     * else statement above so middle should not get set.  OTOH, it 
     * may be possible for the faces to match but be different objects.
     */
    if (top == middle) middle=blank_face;

    /* There are three posibilities at this point:
     * 1) top face is set, need middle to be set.
     * 2) middle is set, need to set top.
     * 3) neither middle or top is set - need to set both.
     */

    for (tmp=last; tmp; tmp=tmp->below) {
        /* Once we get to a floor, stop, since we already have a floor object */
        if (QUERY_FLAG(tmp,FLAG_IS_FLOOR)) break;

        /* If two top faces are already set, quit processing */
        if ((top != blank_face) && (middle != blank_face)) break;

        /* Only show visible faces, unless its the editor - show all */
        if (!tmp->invisible || editor) {
            /* Fill in top if needed */
            if (top == blank_face) {
                top = tmp->face;
                top_obj = tmp;
                if (top == middle) middle=blank_face;
            } else {
                /* top is already set - we should only get here if
                 * middle is not set
                 *
                 * Set the middle face and break out, since there is nothing
                 * more to fill in.  We don't check visiblity here, since
                 * 
                 */
                if (tmp->face  != top ) {
                    middle = tmp->face;
                    middle_obj = tmp;
                    break;
                }
            }
        }
    }
    if (middle == floor) middle = blank_face;
    if (top == middle) middle = blank_face;
    SET_MAP_FACE(m,x,y,top,0);
    if(top != blank_face)
        SET_MAP_FACE_OBJ(m,x,y,top_obj,0);
    else
        SET_MAP_FACE_OBJ(m,x,y,NULL,0);
    SET_MAP_FACE(m,x,y,middle,1);
    if(middle != blank_face)
        SET_MAP_FACE_OBJ(m,x,y,middle_obj,1);
    else
        SET_MAP_FACE_OBJ(m,x,y,NULL,1);
    SET_MAP_FACE(m,x,y,floor,2);
    if(floor != blank_face)
        SET_MAP_FACE_OBJ(m,x,y,floor_obj,2);
    else
        SET_MAP_FACE_OBJ(m,x,y,NULL,2);
    SET_MAP_LIGHT(m,x,y,light);
}


void set_map_reset_time(mapstruct *map) {
    int timeout;

    timeout = MAP_RESET_TIMEOUT(map);
    if (timeout <= 0)
        timeout = MAP_DEFAULTRESET;
    if (timeout >= MAP_MAXRESET)
        timeout = MAP_MAXRESET;
    MAP_WHEN_RESET(map) = seconds()+timeout;
}

/* this updates the orig_map->tile_map[tile_num] value after loading
 * the map.  It also takes care of linking back the freshly loaded
 * maps tile_map values if it tiles back to this one.  It returns
 * the value of orig_map->tile_map[tile_num].  It really only does this
 * so that it is easier for calling functions to verify success.
 */

static mapstruct *load_and_link_tiled_map(mapstruct *orig_map, int tile_num)
{
    int dest_tile = (tile_num +2) % 4;
    char *path = path_combine_and_normalize(orig_map->path, orig_map->tile_path[tile_num]);

    orig_map->tile_map[tile_num] = ready_map_name(path, 0);

    /* need to do a strcmp here as the orig_map->path is not a shared string */
    if (orig_map->tile_map[tile_num]->tile_path[dest_tile] &&
        !strcmp(orig_map->tile_map[tile_num]->tile_path[dest_tile], orig_map->path))
        orig_map->tile_map[tile_num]->tile_map[dest_tile] = orig_map;

    return orig_map->tile_map[tile_num];
}

/* this returns TRUE if the coordinates (x,y) are out of
 * map m.  This function also takes into account any
 * tiling considerations, loading adjacant maps as needed.
 * This is the function should always be used when it
 * necessary to check for valid coordinates.
 * This function will recursively call itself for the 
 * tiled maps.
 *
 * 
 */
int out_of_map(mapstruct *m, int x, int y)
{

    /* If we get passed a null map, this is obviously the
     * case.  This generally shouldn't happen, but if the
     * map loads fail below, it could happen.
     */
    if (!m) return 0;

    if (x<0) {
        if (!m->tile_path[3]) return 1;
        if (!m->tile_map[3] || m->tile_map[3]->in_memory != MAP_IN_MEMORY) {
            load_and_link_tiled_map(m, 3);
        }
        return (out_of_map(m->tile_map[3], x + MAP_WIDTH(m->tile_map[3]), y));
    }
    if (x>=MAP_WIDTH(m)) {
        if (!m->tile_path[1]) return 1;
        if (!m->tile_map[1] || m->tile_map[1]->in_memory != MAP_IN_MEMORY) {
            load_and_link_tiled_map(m, 1);
        }
        return (out_of_map(m->tile_map[1], x - MAP_WIDTH(m), y));
    }
    if (y<0) {
        if (!m->tile_path[0]) return 1;
        if (!m->tile_map[0] || m->tile_map[0]->in_memory != MAP_IN_MEMORY) {
            load_and_link_tiled_map(m, 0);
        }
        return (out_of_map(m->tile_map[0], x, y + MAP_HEIGHT(m->tile_map[0])));
    }
    if (y>=MAP_HEIGHT(m)) {
        if (!m->tile_path[2]) return 1;
        if (!m->tile_map[2] || m->tile_map[2]->in_memory != MAP_IN_MEMORY) {
            load_and_link_tiled_map(m, 2);
        }
        return (out_of_map(m->tile_map[2], x, y - MAP_HEIGHT(m)));
    }

    /* Simple case - coordinates are within this local
     * map.
     */
    return 0;
}

/* This is basically the same as out_of_map above, but
 * instead we return NULL if no map is valid (coordinates
 * out of bounds and no tiled map), otherwise it returns
 * the map as that the coordinates are really on, and 
 * updates x and y to be the localized coordinates.
 * Using this is more efficient of calling out_of_map
 * and then figuring out what the real map is
 */
mapstruct *get_map_from_coord(mapstruct *m, sint16 *x, sint16 *y)
{

    if (*x<0) {
        if (!m->tile_path[3]) return NULL;
        if (!m->tile_map[3] || m->tile_map[3]->in_memory != MAP_IN_MEMORY)
            load_and_link_tiled_map(m, 3);

        *x += MAP_WIDTH(m->tile_map[3]);
        return (get_map_from_coord(m->tile_map[3], x, y));
    }
    if (*x>=MAP_WIDTH(m)) {
        if (!m->tile_path[1]) return NULL;
        if (!m->tile_map[1] || m->tile_map[1]->in_memory != MAP_IN_MEMORY)
            load_and_link_tiled_map(m, 1);

        *x -= MAP_WIDTH(m);
        return (get_map_from_coord(m->tile_map[1], x, y));
    }
    if (*y<0) {
        if (!m->tile_path[0]) return NULL;
        if (!m->tile_map[0] || m->tile_map[0]->in_memory != MAP_IN_MEMORY)
            load_and_link_tiled_map(m, 0);

        *y += MAP_HEIGHT(m->tile_map[0]);
        return (get_map_from_coord(m->tile_map[0], x, y));
    }
    if (*y>=MAP_HEIGHT(m)) {
        if (!m->tile_path[2]) return NULL;
        if (!m->tile_map[2] || m->tile_map[2]->in_memory != MAP_IN_MEMORY)
            load_and_link_tiled_map(m, 2);

        *y -= MAP_HEIGHT(m);
        return (get_map_from_coord(m->tile_map[2], x, y));
    }

    /* Simple case - coordinates are within this local
     * map.
     */

    return m;
}

/**
 * Return whether map2 is adjacent to map1. If so, store the distance from
 * map1 to map2 in dx/dy.
 */
static int adjacent_map(const mapstruct *map1, const mapstruct *map2, int *dx, int *dy) {
    if (!map1 || !map2)
        return 0;

    if (map1 == map2) {
        *dx = 0;
        *dy = 0;

    } else if (map1->tile_map[0] == map2) { /* up */
        *dx = 0;
        *dy = -MAP_HEIGHT(map2);
    } else if (map1->tile_map[1] == map2) { /* right */
        *dx = MAP_WIDTH(map1);
        *dy = 0;
    } else if (map1->tile_map[2] == map2) { /* down */
        *dx = 0;
        *dy = MAP_HEIGHT(map1);
    } else if (map1->tile_map[3] == map2) { /* left */
        *dx = -MAP_WIDTH(map2);
        *dy = 0;

    } else if (map1->tile_map[0] && map1->tile_map[0]->tile_map[1] == map2) { /* up right */
        *dx = MAP_WIDTH(map1->tile_map[0]);
        *dy = -MAP_HEIGHT(map1->tile_map[0]);
    } else if (map1->tile_map[0] && map1->tile_map[0]->tile_map[3] == map2) { /* up left */
        *dx = -MAP_WIDTH(map2);
        *dy = -MAP_HEIGHT(map1->tile_map[0]);
    } else if (map1->tile_map[1] && map1->tile_map[1]->tile_map[0] == map2) { /* right up */
        *dx = MAP_WIDTH(map1);
        *dy = -MAP_HEIGHT(map2);
    } else if (map1->tile_map[1] && map1->tile_map[1]->tile_map[2] == map2) { /* right down */
        *dx = MAP_WIDTH(map1);
        *dy = MAP_HEIGHT(map1->tile_map[1]);
    } else if (map1->tile_map[2] && map1->tile_map[2]->tile_map[1] == map2) { /* down right */
        *dx = MAP_WIDTH(map1->tile_map[2]);
        *dy = MAP_HEIGHT(map1);
    } else if (map1->tile_map[2] && map1->tile_map[2]->tile_map[3] == map2) { /* down left */
        *dx = -MAP_WIDTH(map2);
        *dy = MAP_HEIGHT(map1);
    } else if (map1->tile_map[3] && map1->tile_map[3]->tile_map[0] == map2) { /* left up */
        *dx = -MAP_WIDTH(map1->tile_map[3]);
        *dy = -MAP_HEIGHT(map2);
    } else if (map1->tile_map[3] && map1->tile_map[3]->tile_map[2] == map2) { /* left down */
        *dx = -MAP_WIDTH(map1->tile_map[3]);
        *dy = MAP_HEIGHT(map1->tile_map[3]);

    } else { /* not "adjacent" enough */
        return 0;
    }

    return 1;
}

/* From map.c
 * This is used by get_player to determine where the other
 * creature is.  get_rangevector takes into account map tiling,
 * so you just can not look the the map coordinates and get the
 * righte value.  distance_x/y are distance away, which
 * can be negativbe.  direction is the crossfire direction scheme
 * that the creature should head.  part is the part of the
 * monster that is closest.
 * 
 * get_rangevector looks at op1 and op2, and fills in the
 * structure for op1 to get to op2.
 * We already trust that the caller has verified that the
 * two objects are at least on adjacent maps.  If not,
 * results are not likely to be what is desired.
 * if the objects are not on maps, results are also likely to
 * be unexpected
 *
 * currently, the only flag supported (0x1) is don't translate for
 * closest body part of 'op1'
 */

void get_rangevector(object *op1, object *op2, rv_vector *retval, int flags) {
    if (!adjacent_map(op1->map, op2->map, &retval->distance_x, &retval->distance_y)) {
        /* be conservative and fill in _some_ data */
        retval->distance   = 100000;
        retval->distance_x = 32767;
        retval->distance_y = 32767;
        retval->direction  = 0;
        retval->part       = 0;
    } else {
        object *best;

        retval->distance_x += op2->x-op1->x;
        retval->distance_y += op2->y-op1->y;

        best = op1;
        /* If this is multipart, find the closest part now */
        if (!(flags&0x1) && op1->more) {
            object *tmp;
            int best_distance = retval->distance_x*retval->distance_x+
                                retval->distance_y*retval->distance_y, tmpi;

            /* we just take the offset of the piece to head to figure
             * distance instead of doing all that work above again
             * since the distance fields we set above are positive in the
             * same axis as is used for multipart objects, the simply arithmetic
             * below works.
             */
            for (tmp = op1->more; tmp != NULL; tmp = tmp->more) {
                tmpi = (op1->x-tmp->x+retval->distance_x)*(op1->x-tmp->x+retval->distance_x)+
                       (op1->y-tmp->y+retval->distance_y)*(op1->y-tmp->y+retval->distance_y);
                if (tmpi < best_distance) {
                    best_distance = tmpi;
                    best = tmp;
                }
            }
            if (best != op1) {
                retval->distance_x += op1->x-best->x;
                retval->distance_y += op1->y-best->y;
            }
        }
        retval->part = best;
        retval->distance = isqrt(retval->distance_x*retval->distance_x+retval->distance_y*retval->distance_y);
        retval->direction = find_dir_2(-retval->distance_x, -retval->distance_y);
    }
}

/* this is basically the same as get_rangevector above, but instead of 
 * the first parameter being an object, it instead is the map
 * and x,y coordinates - this is used for path to player - 
 * since the object is not infact moving but we are trying to traverse
 * the path, we need this.
 * flags has no meaning for this function at this time - I kept it in to
 * be more consistant with the above function and also in case they are needed
 * for something in the future.  Also, since no object is pasted, the best
 * field of the rv_vector is set to NULL.
 */

void get_rangevector_from_mapcoord(const mapstruct *m, int x, int y, const object *op2, rv_vector *retval, int flags) {
    if (!adjacent_map(m, op2->map, &retval->distance_x, &retval->distance_y)) {
        /* be conservative and fill in _some_ data */
        retval->distance   = 100000;
        retval->distance_x = 32767;
        retval->distance_y = 32767;
        retval->direction  = 0;
        retval->part       = 0;
    } else {
        retval->distance_x += op2->x-x;
        retval->distance_y += op2->y-y;

        retval->part = NULL;
        retval->distance = isqrt(retval->distance_x*retval->distance_x+retval->distance_y*retval->distance_y);
        retval->direction = find_dir_2(-retval->distance_x, -retval->distance_y);
    }
}

/* Returns true of op1 and op2 are effectively on the same map
 * (as related to map tiling).  Note that this looks for a path from
 * op1 to op2, so if the tiled maps are assymetric and op2 has a path
 * to op1, this will still return false.
 * Note we only look one map out to keep the processing simple
 * and efficient.  This could probably be a macro.
 * MSW 2001-08-05
 */
int on_same_map(const object *op1, const object *op2) {
    int dx, dy;

    return adjacent_map(op1->map, op2->map, &dx, &dy);
}
Revision:	1.22
Committed:	Mon Sep 4 11:07:59 2006 UTC (17 years, 9 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.21:	+5 -3 lines
Log Message:	Changes... - alternative shstr representation, saves code - use glibs splice memory allocator (seems slower) - use simpler memory/lifetime management for objects, no recycling