mob_prog.c

Go to the documentation of this file.

/***************************************************************************
 *  Original Diku Mud copyright (C) 1990, 1991 by Sebastian Hammer,        *
 *  Michael Seifert, Hans Henrik Strfeldt, Tom Madsen, and Katja Nyboe.    *
 *                                                                         *
 *  Merc Diku Mud improvments copyright (C) 1992, 1993 by Michael          *
 *  Chastain, Michael Quan, and Mitchell Tse.                              *
 *                                                                         *
 *  In order to use any part of this Merc Diku Mud, you must comply with   *
 *  both the original Diku license in 'license.doc' as well the Merc       *
 *  license in 'license.txt'.  In particular, you may not remove either of *
 *  these copyright notices.                                               *
 *                                                                         *
 *  Much time and thought has gone into this software and you are          *
 *  benefitting.  We hope that you share your changes too.  What goes      *
 *  around, comes around.                                                  *
 ***************************************************************************/

/***************************************************************************
 *  ROM 2.4 is copyright 1993-1998 Russ Taylor                             *
 *  ROM has been brought to you by the ROM consortium                      *
 *      Russ Taylor (rtaylor@hypercube.org)                                *
 *      Gabrielle Taylor (gtaylor@hypercube.org)                           *
 *      Brian Moore (zump@rom.org)                                         *
 *  By using this code, you have agreed to follow the terms of the         *
 *  ROM license, in the file Rom24/doc/rom.license                         *
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *  MOBprograms for ROM 2.4 v0.98g (C) M.Nylander 1996                     *
 *  Based on MERC 2.2 MOBprograms concept by N'Atas-ha.                    *
 *  Written and adapted to ROM 2.4 by                                      *
 *          Markku Nylander (markku.nylander@uta.fi)                       *
 *  This code may be copied and distributed as per the ROM license.        *
 *                                                                         *
 ***************************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <sys/types.h>
#include <ctype.h>
#include "merc.h"
#include "tables.h"
#include "lookup.h"

extern int flag_lookup (const char *word, const struct flag_type *flag_table);

/*
 * These defines correspond to the entries in fn_keyword[] table.
 * If you add a new if_check, you must also add a #define here.
 */
#define CHK_RAND       (0)
#define CHK_MOBHERE     (1)
#define CHK_OBJHERE     (2)
#define CHK_MOBEXISTS   (3)
#define CHK_OBJEXISTS   (4)
#define CHK_PEOPLE      (5)
#define CHK_PLAYERS     (6)
#define CHK_MOBS        (7)
#define CHK_CLONES      (8)
#define CHK_ORDER       (9)
#define CHK_HOUR        (10)
#define CHK_ISPC        (11)
#define CHK_ISNPC       (12)
#define CHK_ISGOOD      (13)
#define CHK_ISEVIL      (14)
#define CHK_ISNEUTRAL   (15)
#define CHK_ISIMMORT    (16)
#define CHK_ISCHARM     (17)
#define CHK_ISFOLLOW    (18)
#define CHK_ISACTIVE    (19)
#define CHK_ISDELAY     (20)
#define CHK_ISVISIBLE   (21)
#define CHK_HASTARGET   (22)
#define CHK_ISTARGET    (23)
#define CHK_EXISTS      (24)
#define CHK_AFFECTED    (25)
#define CHK_ACT         (26)
#define CHK_OFF         (27)
#define CHK_IMM         (28)
#define CHK_CARRIES     (29)
#define CHK_WEARS       (30)
#define CHK_HAS         (31)
#define CHK_USES        (32)
#define CHK_NAME        (33)
#define CHK_POS         (34)
#define CHK_CLAN        (35)
#define CHK_RACE        (36)
#define CHK_CLASS       (37)
#define CHK_OBJTYPE     (38)
#define CHK_VNUM        (39)
#define CHK_HPCNT       (40)
#define CHK_ROOM        (41)
#define CHK_SEX         (42)
#define CHK_LEVEL       (43)
#define CHK_ALIGN       (44)
#define CHK_MONEY       (45)
#define CHK_OBJVAL0     (46)
#define CHK_OBJVAL1     (47)
#define CHK_OBJVAL2     (48)
#define CHK_OBJVAL3     (49)
#define CHK_OBJVAL4     (50)
#define CHK_GRPSIZE     (51)

/*
 * These defines correspond to the entries in fn_evals[] table.
 */
#define EVAL_EQ            0
#define EVAL_GE            1
#define EVAL_LE            2
#define EVAL_GT            3
#define EVAL_LT            4
#define EVAL_NE            5

/*
 * if-check keywords:
 */
const char *fn_keyword[] = {
    "rand",                        /* if rand 30       - if random number < 30 */
    "mobhere",                    /* if mobhere fido  - is there a 'fido' here */
    "objhere",                    /* if objhere bottle    - is there a 'bottle' here */
    /* if mobhere 1233  - is there mob vnum 1233 here */
    /* if objhere 1233  - is there obj vnum 1233 here */
    "mobexists",                /* if mobexists fido    - is there a fido somewhere */
    "objexists",                /* if objexists sword   - is there a sword somewhere */

    "people",                    /* if people > 4    - does room contain > 4 people */
    "players",                    /* if players > 1   - does room contain > 1 pcs */
    "mobs",                        /* if mobs > 2      - does room contain > 2 mobiles */
    "clones",                    /* if clones > 3    - are there > 3 mobs of same vnum here */
    "order",                    /* if order == 0    - is mob the first in room */
    "hour",                        /* if hour > 11     - is the time > 11 o'clock */


    "ispc",                        /* if ispc $n       - is $n a pc */
    "isnpc",                    /* if isnpc $n      - is $n a mobile */
    "isgood",                    /* if isgood $n     - is $n good */
    "isevil",                    /* if isevil $n     - is $n evil */
    "isneutral",                /* if isneutral $n  - is $n neutral */
    "isimmort",                    /* if isimmort $n   - is $n immortal */
    "ischarm",                    /* if ischarm $n    - is $n charmed */
    "isfollow",                    /* if isfollow $n   - is $n following someone */
    "isactive",                    /* if isactive $n   - is $n's position > SLEEPING */
    "isdelay",                    /* if isdelay $i    - does $i have mobprog pending */
    "isvisible",                /* if isvisible $n  - can mob see $n */
    "hastarget",                /* if hastarget $i  - does $i have a valid target */
    "istarget",                    /* if istarget $n   - is $n mob's target */
    "exists",                    /* if exists $n     - does $n exist somewhere */

    "affected",                    /* if affected $n blind - is $n affected by blind */
    "act",                        /* if act $i sentinel   - is $i flagged sentinel */
    "off",                        /* if off $i berserk    - is $i flagged berserk */
    "imm",                        /* if imm $i fire   - is $i immune to fire */
    "carries",                    /* if carries $n sword  - does $n have a 'sword' */
    /* if carries $n 1233   - does $n have obj vnum 1233 */
    "wears",                    /* if wears $n lantern  - is $n wearing a 'lantern' */
    /* if wears $n 1233 - is $n wearing obj vnum 1233 */
    "has",                        /* if has $n weapon - does $n have obj of type weapon */
    "uses",                        /* if uses $n armor - is $n wearing obj of type armor */
    "name",                        /* if name $n puff  - is $n's name 'puff' */
    "pos",                        /* if pos $n standing   - is $n standing */
    "clan",                        /* if clan $n 'whatever'- does $n belong to clan 'whatever' */
    "race",                        /* if race $n dragon    - is $n of 'dragon' race */
    "class",                    /* if class $n mage - is $n's class 'mage' */
    "objtype",                    /* if objtype $p scroll - is $p a scroll */

    "vnum",                        /* if vnum $i == 1233   - virtual number check */
    "hpcnt",                    /* if hpcnt $i > 30 - hit point percent check */
    "room",                        /* if room $i == 1233   - room virtual number */
    "sex",                        /* if sex $i == 0   - sex check */
    "level",                    /* if level $n < 5  - level check */
    "align",                    /* if align $n < -1000  - alignment check */
    "money",                    /* if money $n */
    "objval0",                    /* if objval0 > 1000    - object value[] checks 0..4 */
    "objval1",
    "objval2",
    "objval3",
    "objval4",
    "grpsize",                    /* if grpsize $n > 6    - group size check */

    "\n"                        /* Table terminator */
};

const char *fn_evals[] = {
    "==",
    ">=",
    "<=",
    ">",
    "<",
    "!=",
    "\n"
};

/*
 * Return a valid keyword from a keyword table
 */
int keyword_lookup (const char **table, char *keyword)
{
    register int i;
    for (i = 0; table[i][0] != '\n'; i++)
        if (!str_cmp (table[i], keyword))
            return (i);
    return -1;
}

/*
 * Perform numeric evaluation.
 * Called by cmd_eval()
 */
int num_eval (int lval, int oper, int rval)
{
    switch (oper)
    {
        case EVAL_EQ:
            return (lval == rval);
        case EVAL_GE:
            return (lval >= rval);
        case EVAL_LE:
            return (lval <= rval);
        case EVAL_NE:
            return (lval != rval);
        case EVAL_GT:
            return (lval > rval);
        case EVAL_LT:
            return (lval < rval);
        default:
            bug ("num_eval: invalid oper", 0);
            return 0;
    }
}

/*
 * ---------------------------------------------------------------------
 * UTILITY FUNCTIONS USED BY CMD_EVAL()
 * ----------------------------------------------------------------------
 */

/*
 * Get a random PC in the room (for $r parameter)
 */
CHAR_DATA *get_random_char (CHAR_DATA * mob)
{
    CHAR_DATA *vch, *victim = NULL;
    int now = 0, highest = 0;
    for (vch = mob->in_room->people; vch; vch = vch->next_in_room)
    {
        if (mob != vch && !IS_NPC (vch)
            && can_see (mob, vch) && (now = number_percent ()) > highest)
        {
            victim = vch;
            highest = now;
        }
    }
    return victim;
}

/* 
 * How many other players / mobs are there in the room
 * iFlag: 0: all, 1: players, 2: mobiles 3: mobs w/ same vnum 4: same group
 */
int count_people_room (CHAR_DATA * mob, int iFlag)
{
    CHAR_DATA *vch;
    int count;
    for (count = 0, vch = mob->in_room->people; vch; vch = vch->next_in_room)
        if (mob != vch && (iFlag == 0 || (iFlag == 1 && !IS_NPC (vch))
                           || (iFlag == 2 && IS_NPC (vch))
                           || (iFlag == 3 && IS_NPC (mob) && IS_NPC (vch)
                               && mob->pIndexData->vnum ==
                               vch->pIndexData->vnum) || (iFlag == 4
                                                          &&
                                                          is_same_group (mob,
                                                                         vch)))
            && can_see (mob, vch))
            count++;
    return (count);
}

/*
 * Get the order of a mob in the room. Useful when several mobs in
 * a room have the same trigger and you want only the first of them
 * to act 
 */
int get_order (CHAR_DATA * ch)
{
    CHAR_DATA *vch;
    int i;

    if (!IS_NPC (ch))
        return 0;
    for (i = 0, vch = ch->in_room->people; vch; vch = vch->next_in_room)
    {
        if (vch == ch)
            return i;
        if (IS_NPC (vch) && vch->pIndexData->vnum == ch->pIndexData->vnum)
            i++;
    }
    return 0;
}

/*
 * Check if ch has a given item or item type
 * vnum: item vnum or -1
 * item_type: item type or -1
 * fWear: TRUE: item must be worn, FALSE: don't care
 */
bool has_item (CHAR_DATA * ch, int vnum, sh_int item_type, bool fWear)
{
    OBJ_DATA *obj;
    for (obj = ch->carrying; obj; obj = obj->next_content)
        if ((vnum < 0 || obj->pIndexData->vnum == vnum)
            && (item_type < 0 || obj->pIndexData->item_type == item_type)
            && (!fWear || obj->wear_loc != WEAR_NONE))
            return TRUE;
    return FALSE;
}

/*
 * Check if there's a mob with given vnum in the room
 */
bool get_mob_vnum_room (CHAR_DATA * ch, int vnum)
{
    CHAR_DATA *mob;
    for (mob = ch->in_room->people; mob; mob = mob->next_in_room)
        if (IS_NPC (mob) && mob->pIndexData->vnum == vnum)
            return TRUE;
    return FALSE;
}

/*
 * Check if there's an object with given vnum in the room
 */
bool get_obj_vnum_room (CHAR_DATA * ch, int vnum)
{
    OBJ_DATA *obj;
    for (obj = ch->in_room->contents; obj; obj = obj->next_content)
        if (obj->pIndexData->vnum == vnum)
            return TRUE;
    return FALSE;
}

/* ---------------------------------------------------------------------
 * CMD_EVAL
 * This monster evaluates an if/or/and statement
 * There are five kinds of statement:
 * 1) keyword and value (no $-code)        if random 30
 * 2) keyword, comparison and value        if people > 2
 * 3) keyword and actor                    if isnpc $n
 * 4) keyword, actor and value            if carries $n sword
 * 5) keyword, actor, comparison and value  if level $n >= 10
 *
 *----------------------------------------------------------------------
 */
int cmd_eval (int vnum, char *line, int check,
              CHAR_DATA * mob, CHAR_DATA * ch,
              const void *arg1, const void *arg2, CHAR_DATA * rch)
{
    CHAR_DATA *lval_char = mob;
    CHAR_DATA *vch = (CHAR_DATA *) arg2;
    OBJ_DATA *obj1 = (OBJ_DATA *) arg1;
    OBJ_DATA *obj2 = (OBJ_DATA *) arg2;
    OBJ_DATA *lval_obj = NULL;

    char *original, buf[MAX_INPUT_LENGTH], code;
    int lval = 0, oper = 0, rval = -1;

    original = line;
    line = one_argument (line, buf);
    if (buf[0] == '\0' || mob == NULL)
        return FALSE;

    /*
     * If this mobile has no target, let's assume our victim is the one
     */
    if (mob->mprog_target == NULL)
        mob->mprog_target = ch;

    switch (check)
    {
            /*
             * Case 1: keyword and value
             */
        case CHK_RAND:
            return (atoi (buf) < number_percent ());
        case CHK_MOBHERE:
            if (is_number (buf))
                return (get_mob_vnum_room (mob, atoi (buf)));
            else
                return ((bool) (get_char_room (mob, buf) != NULL));
        case CHK_OBJHERE:
            if (is_number (buf))
                return (get_obj_vnum_room (mob, atoi (buf)));
            else
                return ((bool) (get_obj_here (mob, buf) != NULL));
        case CHK_MOBEXISTS:
            return ((bool) (get_char_world (mob, buf) != NULL));
        case CHK_OBJEXISTS:
            return ((bool) (get_obj_world (mob, buf) != NULL));
            /*
             * Case 2 begins here: We sneakily use rval to indicate need
             *             for numeric eval...
             */
        case CHK_PEOPLE:
            rval = count_people_room (mob, 0);
            break;
        case CHK_PLAYERS:
            rval = count_people_room (mob, 1);
            break;
        case CHK_MOBS:
            rval = count_people_room (mob, 2);
            break;
        case CHK_CLONES:
            rval = count_people_room (mob, 3);
            break;
        case CHK_ORDER:
            rval = get_order (mob);
            break;
        case CHK_HOUR:
            rval = time_info.hour;
            break;
        default:;
    }

    /*
     * Case 2 continued: evaluate expression
     */
    if (rval >= 0)
    {
        if ((oper = keyword_lookup (fn_evals, buf)) < 0)
        {
            sprintf (buf, "Cmd_eval: prog %d syntax error(2) '%s'",
                     vnum, original);
            bug (buf, 0);
            return FALSE;
        }
        one_argument (line, buf);
        lval = rval;
        rval = atoi (buf);
        return (num_eval (lval, oper, rval));
    }

    /*
     * Case 3,4,5: Grab actors from $* codes
     */
    if (buf[0] != '$' || buf[1] == '\0')
    {
        sprintf (buf, "Cmd_eval: prog %d syntax error(3) '%s'",
                 vnum, original);
        bug (buf, 0);
        return FALSE;
    }
    else
        code = buf[1];
    switch (code)
    {
        case 'i':
            lval_char = mob;
            break;
        case 'n':
            lval_char = ch;
            break;
        case 't':
            lval_char = vch;
            break;
        case 'r':
            lval_char = rch == NULL ? get_random_char (mob) : rch;
            break;
        case 'o':
            lval_obj = obj1;
            break;
        case 'p':
            lval_obj = obj2;
            break;
        case 'q':
            lval_char = mob->mprog_target;
            break;
        default:
            sprintf (buf, "Cmd_eval: prog %d syntax error(4) '%s'",
                     vnum, original);
            bug (buf, 0);
            return FALSE;
    }
    /*
     * From now on, we need an actor, so if none was found, bail out
     */
    if (lval_char == NULL && lval_obj == NULL)
        return FALSE;

    /*
     * Case 3: Keyword, comparison and value
     */
    switch (check)
    {
        case CHK_ISPC:
            return (lval_char != NULL && !IS_NPC (lval_char));
        case CHK_ISNPC:
            return (lval_char != NULL && IS_NPC (lval_char));
        case CHK_ISGOOD:
            return (lval_char != NULL && IS_GOOD (lval_char));
        case CHK_ISEVIL:
            return (lval_char != NULL && IS_EVIL (lval_char));
        case CHK_ISNEUTRAL:
            return (lval_char != NULL && IS_NEUTRAL (lval_char));
        case CHK_ISIMMORT:
            return (lval_char != NULL && IS_IMMORTAL (lval_char));
        case CHK_ISCHARM:        /* A relic from MERC 2.2 MOBprograms */
            return (lval_char != NULL && IS_AFFECTED (lval_char, AFF_CHARM));
        case CHK_ISFOLLOW:
            return (lval_char != NULL && lval_char->master != NULL
                    && lval_char->master->in_room == lval_char->in_room);
        case CHK_ISACTIVE:
            return (lval_char != NULL && lval_char->position > POS_SLEEPING);
        case CHK_ISDELAY:
            return (lval_char != NULL && lval_char->mprog_delay > 0);
        case CHK_ISVISIBLE:
            switch (code)
            {
                default:
                case 'i':
                case 'n':
                case 't':
                case 'r':
                case 'q':
                    return (lval_char != NULL && can_see (mob, lval_char));
                case 'o':
                case 'p':
                    return (lval_obj != NULL && can_see_obj (mob, lval_obj));
            }
        case CHK_HASTARGET:
            return (lval_char != NULL && lval_char->mprog_target != NULL
                    && lval_char->in_room ==
                    lval_char->mprog_target->in_room);
        case CHK_ISTARGET:
            return (lval_char != NULL && mob->mprog_target == lval_char);
        default:;
    }

    /* 
     * Case 4: Keyword, actor and value
     */
    line = one_argument (line, buf);
    switch (check)
    {
        case CHK_AFFECTED:
            return (lval_char != NULL
                    && IS_SET (lval_char->affected_by,
                               flag_lookup (buf, affect_flags)));
        case CHK_ACT:
            return (lval_char != NULL
                    && IS_SET (lval_char->act, flag_lookup (buf, act_flags)));
        case CHK_IMM:
            return (lval_char != NULL
                    && IS_SET (lval_char->imm_flags,
                               flag_lookup (buf, imm_flags)));
        case CHK_OFF:
            return (lval_char != NULL
                    && IS_SET (lval_char->off_flags,
                               flag_lookup (buf, off_flags)));
        case CHK_CARRIES:
            if (is_number (buf))
                return (lval_char != NULL
                        && has_item (lval_char, atoi (buf), -1, FALSE));
            else
                return (lval_char != NULL
                        && (get_obj_carry (lval_char, buf, lval_char) !=
                            NULL));
        case CHK_WEARS:
            if (is_number (buf))
                return (lval_char != NULL
                        && has_item (lval_char, atoi (buf), -1, TRUE));
            else
                return (lval_char != NULL
                        && (get_obj_wear (lval_char, buf) != NULL));
        case CHK_HAS:
            return (lval_char != NULL
                    && has_item (lval_char, -1, item_lookup (buf), FALSE));
        case CHK_USES:
            return (lval_char != NULL
                    && has_item (lval_char, -1, item_lookup (buf), TRUE));
        case CHK_NAME:
            switch (code)
            {
                default:
                case 'i':
                case 'n':
                case 't':
                case 'r':
                case 'q':
                    return (lval_char != NULL
                            && is_name (buf, lval_char->name));
                case 'o':
                case 'p':
                    return (lval_obj != NULL
                            && is_name (buf, lval_obj->name));
            }
        case CHK_POS:
            return (lval_char != NULL
                    && lval_char->position == position_lookup (buf));
        case CHK_CLAN:
            return (lval_char != NULL
                    && lval_char->clan == clan_lookup (buf));
        case CHK_RACE:
            return (lval_char != NULL
                    && lval_char->race == race_lookup (buf));
        case CHK_CLASS:
            return (lval_char != NULL
                    && lval_char->class == class_lookup (buf));
        case CHK_OBJTYPE:
            return (lval_obj != NULL
                    && lval_obj->item_type == item_lookup (buf));
        default:;
    }

    /*
     * Case 5: Keyword, actor, comparison and value
     */
    if ((oper = keyword_lookup (fn_evals, buf)) < 0)
    {
        sprintf (buf, "Cmd_eval: prog %d syntax error(5): '%s'",
                 vnum, original);
        bug (buf, 0);
        return FALSE;
    }
    one_argument (line, buf);
    rval = atoi (buf);

    switch (check)
    {
        case CHK_VNUM:
            switch (code)
            {
                default:
                case 'i':
                case 'n':
                case 't':
                case 'r':
                case 'q':
                    if (lval_char != NULL && IS_NPC (lval_char))
                        lval = lval_char->pIndexData->vnum;
                    break;
                case 'o':
                case 'p':
                    if (lval_obj != NULL)
                        lval = lval_obj->pIndexData->vnum;
            }
            break;
        case CHK_HPCNT:
            if (lval_char != NULL)
                lval =
                    (lval_char->hit * 100) / (UMAX (1, lval_char->max_hit));
            break;
        case CHK_ROOM:
            if (lval_char != NULL && lval_char->in_room != NULL)
                lval = lval_char->in_room->vnum;
            break;
        case CHK_SEX:
            if (lval_char != NULL)
                lval = lval_char->sex;
            break;
        case CHK_LEVEL:
            if (lval_char != NULL)
                lval = lval_char->level;
            break;
        case CHK_ALIGN:
            if (lval_char != NULL)
                lval = lval_char->alignment;
            break;
        case CHK_MONEY:        /* Money is converted to silver... */
            if (lval_char != NULL)
                lval = lval_char->gold + (lval_char->silver * 100);
            break;
        case CHK_OBJVAL0:
            if (lval_obj != NULL)
                lval = lval_obj->value[0];
            break;
        case CHK_OBJVAL1:
            if (lval_obj != NULL)
                lval = lval_obj->value[1];
            break;
        case CHK_OBJVAL2:
            if (lval_obj != NULL)
                lval = lval_obj->value[2];
            break;
        case CHK_OBJVAL3:
            if (lval_obj != NULL)
                lval = lval_obj->value[3];
            break;
        case CHK_OBJVAL4:
            if (lval_obj != NULL)
                lval = lval_obj->value[4];
            break;
        case CHK_GRPSIZE:
            if (lval_char != NULL)
                lval = count_people_room (lval_char, 4);
            break;
        default:
            return FALSE;
    }
    return (num_eval (lval, oper, rval));
}

/*
 * ------------------------------------------------------------------------
 * EXPAND_ARG
 * This is a hack of act() in comm.c. I've added some safety guards,
 * so that missing or invalid $-codes do not crash the server
 * ------------------------------------------------------------------------
 */
void expand_arg (char *buf,
                 const char *format,
                 CHAR_DATA * mob, CHAR_DATA * ch,
                 const void *arg1, const void *arg2, CHAR_DATA * rch)
{
    static char *const he_she[] = { "it", "he", "she" };
    static char *const him_her[] = { "it", "him", "her" };
    static char *const his_her[] = { "its", "his", "her" };
    const char *someone = "someone";
    const char *something = "something";
    const char *someones = "someone's";

    char fname[MAX_INPUT_LENGTH];
    CHAR_DATA *vch = (CHAR_DATA *) arg2;
    OBJ_DATA *obj1 = (OBJ_DATA *) arg1;
    OBJ_DATA *obj2 = (OBJ_DATA *) arg2;
    const char *str;
    const char *i;
    char *point;

    /*
     * Discard null and zero-length messages.
     */
    if (format == NULL || format[0] == '\0')
        return;

    point = buf;
    str = format;
    while (*str != '\0')
    {
        if (*str != '$')
        {
            *point++ = *str++;
            continue;
        }
        ++str;

        switch (*str)
        {
            default:
                bug ("Expand_arg: bad code %d.", *str);
                i = " <@@@> ";
                break;
            case 'i':
                one_argument (mob->name, fname);
                i = fname;
                break;
            case 'I':
                i = mob->short_descr;
                break;
            case 'n':
                i = someone;
                if (ch != NULL && can_see (mob, ch))
                {
                    one_argument (ch->name, fname);
                    i = capitalize (fname);
                }
                break;
            case 'N':
                i = (ch != NULL && can_see (mob, ch))
                    ? (IS_NPC (ch) ? ch->short_descr : ch->name) : someone;
                break;
            case 't':
                i = someone;
                if (vch != NULL && can_see (mob, vch))
                {
                    one_argument (vch->name, fname);
                    i = capitalize (fname);
                }
                break;
            case 'T':
                i = (vch != NULL && can_see (mob, vch))
                    ? (IS_NPC (vch) ? vch->short_descr : vch->name) : someone;
                break;
            case 'r':
                if (rch == NULL)
                    rch = get_random_char (mob);
                i = someone;
                if (rch != NULL && can_see (mob, rch))
                {
                    one_argument (rch->name, fname);
                    i = capitalize (fname);
                }
                break;
            case 'R':
                if (rch == NULL)
                    rch = get_random_char (mob);
                i = (rch != NULL && can_see (mob, rch))
                    ? (IS_NPC (ch) ? ch->short_descr : ch->name) : someone;
                break;
            case 'q':
                i = someone;
                if (mob->mprog_target != NULL
                    && can_see (mob, mob->mprog_target))
                {
                    one_argument (mob->mprog_target->name, fname);
                    i = capitalize (fname);
                }
                break;
            case 'Q':
                i = (mob->mprog_target != NULL
                     && can_see (mob,
                                 mob->
                                 mprog_target)) ? (IS_NPC (mob->mprog_target)
                                                   ? mob->
                                                   mprog_target->short_descr :
                                                   mob->mprog_target->name) :
                    someone;
                break;
            case 'j':
                i = he_she[URANGE (0, mob->sex, 2)];
                break;
            case 'e':
                i = (ch != NULL && can_see (mob, ch))
                    ? he_she[URANGE (0, ch->sex, 2)] : someone;
                break;
            case 'E':
                i = (vch != NULL && can_see (mob, vch))
                    ? he_she[URANGE (0, vch->sex, 2)] : someone;
                break;
            case 'J':
                i = (rch != NULL && can_see (mob, rch))
                    ? he_she[URANGE (0, rch->sex, 2)] : someone;
                break;
            case 'X':
                i = (mob->mprog_target != NULL
                     && can_see (mob, mob->mprog_target)) ? he_she[URANGE (0,
                                                                           mob->mprog_target->sex,
                                                                           2)]
                    : someone; break;
            case 'k':
                i = him_her[URANGE (0, mob->sex, 2)];
                break;
            case 'm':
                i = (ch != NULL && can_see (mob, ch))
                    ? him_her[URANGE (0, ch->sex, 2)] : someone;
                break;
            case 'M':
                i = (vch != NULL && can_see (mob, vch))
                    ? him_her[URANGE (0, vch->sex, 2)] : someone;
                break;
            case 'K':
                if (rch == NULL)
                    rch = get_random_char (mob);
                i = (rch != NULL && can_see (mob, rch))
                    ? him_her[URANGE (0, rch->sex, 2)] : someone;
                break;
            case 'Y':
                i = (mob->mprog_target != NULL
                     && can_see (mob, mob->mprog_target)) ? him_her[URANGE (0,
                                                                            mob->mprog_target->sex,
                                                                            2)]
                    : someone; break;
            case 'l':
                i = his_her[URANGE (0, mob->sex, 2)];
                break;
            case 's':
                i = (ch != NULL && can_see (mob, ch))
                    ? his_her[URANGE (0, ch->sex, 2)] : someones;
                break;
            case 'S':
                i = (vch != NULL && can_see (mob, vch))
                    ? his_her[URANGE (0, vch->sex, 2)] : someones;
                break;
            case 'L':
                if (rch == NULL)
                    rch = get_random_char (mob);
                i = (rch != NULL && can_see (mob, rch))
                    ? his_her[URANGE (0, rch->sex, 2)] : someones;
                break;
            case 'Z':
                i = (mob->mprog_target != NULL
                     && can_see (mob, mob->mprog_target)) ? his_her[URANGE (0,
                                                                            mob->mprog_target->sex,
                                                                            2)]
                    : someones; break;
            case 'o':
                i = something;
                if (obj1 != NULL && can_see_obj (mob, obj1))
                {
                    one_argument (obj1->name, fname);
                    i = fname;
                }
                break;
            case 'O':
                i = (obj1 != NULL && can_see_obj (mob, obj1))
                    ? obj1->short_descr : something;
                break;
            case 'p':
                i = something;
                if (obj2 != NULL && can_see_obj (mob, obj2))
                {
                    one_argument (obj2->name, fname);
                    i = fname;
                }
                break;
            case 'P':
                i = (obj2 != NULL && can_see_obj (mob, obj2))
                    ? obj2->short_descr : something;
                break;
        }

        ++str;
        while ((*point = *i) != '\0')
            ++point, ++i;

    }
    *point = '\0';

    return;
}

/*
 * ------------------------------------------------------------------------
 *  PROGRAM_FLOW
 *  This is the program driver. It parses the mob program code lines
 *  and passes "executable" commands to interpret()
 *  Lines beginning with 'mob' are passed to mob_interpret() to handle
 *  special mob commands (in mob_cmds.c)
 *-------------------------------------------------------------------------
 */

#define MAX_NESTED_LEVEL 12        /* Maximum nested if-else-endif's (stack size) */
#define BEGIN_BLOCK       0        /* Flag: Begin of if-else-endif block */
#define IN_BLOCK         -1        /* Flag: Executable statements */
#define END_BLOCK        -2        /* Flag: End of if-else-endif block */
#define MAX_CALL_LEVEL    10        /* Maximum nested calls */

void program_flow (int pvnum,    /* For diagnostic purposes */
                   char *source,    /* the actual MOBprog code */
                   CHAR_DATA * mob, CHAR_DATA * ch, const void *arg1,
                   const void *arg2)
{
    CHAR_DATA *rch = NULL;
    char *code, *line;
    char buf[MAX_STRING_LENGTH];
    char control[MAX_INPUT_LENGTH], data[MAX_STRING_LENGTH];

    static int call_level;        /* Keep track of nested "mpcall"s */

    int level, eval, check;
    int state[MAX_NESTED_LEVEL],    /* Block state (BEGIN,IN,END) */
      cond[MAX_NESTED_LEVEL];    /* Boolean value based on the last if-check */

    sh_int mvnum = mob->pIndexData->vnum;

    if (++call_level > MAX_CALL_LEVEL)
    {
        bug ("MOBprogs: MAX_CALL_LEVEL exceeded, vnum %d",
             mob->pIndexData->vnum);
        return;
    }

    /*
     * Reset "stack"
     */
    for (level = 0; level < MAX_NESTED_LEVEL; level++)
    {
        state[level] = IN_BLOCK;
        cond[level] = TRUE;
    }
    level = 0;

    code = source;
    /*
     * Parse the MOBprog code
     */
    while (*code)
    {
        bool first_arg = TRUE;
        char *b = buf, *c = control, *d = data;
        /*
         * Get a command line. We sneakily get both the control word
         * (if/and/or) and the rest of the line in one pass.
         */
        while (isspace (*code) && *code)
            code++;
        while (*code)
        {
            if (*code == '\n' || *code == '\r')
                break;
            else if (isspace (*code))
            {
                if (first_arg)
                    first_arg = FALSE;
                else
                    *d++ = *code;
            }
            else
            {
                if (first_arg)
                    *c++ = *code;
                else
                    *d++ = *code;
            }
            *b++ = *code++;
        }
        *b = *c = *d = '\0';

        if (buf[0] == '\0')
            break;
        if (buf[0] == '*')        /* Comment */
            continue;

        line = data;
        /* 
         * Match control words
         */
        if (!str_cmp (control, "if"))
        {
            if (state[level] == BEGIN_BLOCK)
            {
                sprintf (buf,
                         "Mobprog: misplaced if statement, mob %d prog %d",
                         mvnum, pvnum);
                bug (buf, 0);
                return;
            }
            state[level] = BEGIN_BLOCK;
            if (++level >= MAX_NESTED_LEVEL)
            {
                sprintf (buf,
                         "Mobprog: Max nested level exceeded, mob %d prog %d",
                         mvnum, pvnum);
                bug (buf, 0);
                return;
            }
            if (level && cond[level - 1] == FALSE)
            {
                cond[level] = FALSE;
                continue;
            }
            line = one_argument (line, control);
            if ((check = keyword_lookup (fn_keyword, control)) >= 0)
            {
                cond[level] =
                    cmd_eval (pvnum, line, check, mob, ch, arg1, arg2, rch);
            }
            else
            {
                sprintf (buf,
                         "Mobprog: invalid if_check (if), mob %d prog %d",
                         mvnum, pvnum);
                bug (buf, 0);
                return;
            }
            state[level] = END_BLOCK;
        }
        else if (!str_cmp (control, "or"))
        {
            if (!level || state[level - 1] != BEGIN_BLOCK)
            {
                sprintf (buf, "Mobprog: or without if, mob %d prog %d",
                         mvnum, pvnum);
                bug (buf, 0);
                return;
            }
            if (level && cond[level - 1] == FALSE)
                continue;
            line = one_argument (line, control);
            if ((check = keyword_lookup (fn_keyword, control)) >= 0)
            {
                eval =
                    cmd_eval (pvnum, line, check, mob, ch, arg1, arg2, rch);
            }
            else
            {
                sprintf (buf,
                         "Mobprog: invalid if_check (or), mob %d prog %d",
                         mvnum, pvnum);
                bug (buf, 0);
                return;
            }
            cond[level] = (eval == TRUE) ? TRUE : cond[level];
        }
        else if (!str_cmp (control, "and"))
        {
            if (!level || state[level - 1] != BEGIN_BLOCK)
            {
                sprintf (buf, "Mobprog: and without if, mob %d prog %d",
                         mvnum, pvnum);
                bug (buf, 0);
                return;
            }
            if (level && cond[level - 1] == FALSE)
                continue;
            line = one_argument (line, control);
            if ((check = keyword_lookup (fn_keyword, control)) >= 0)
            {
                eval =
                    cmd_eval (pvnum, line, check, mob, ch, arg1, arg2, rch);
            }
            else
            {
                sprintf (buf,
                         "Mobprog: invalid if_check (and), mob %d prog %d",
                         mvnum, pvnum);
                bug (buf, 0);
                return;
            }
            cond[level] = (cond[level] == TRUE)
                && (eval == TRUE) ? TRUE : FALSE;
        }
        else if (!str_cmp (control, "endif"))
        {
            if (!level || state[level - 1] != BEGIN_BLOCK)
            {
                sprintf (buf, "Mobprog: endif without if, mob %d prog %d",
                         mvnum, pvnum);
                bug (buf, 0);
                return;
            }
            cond[level] = TRUE;
            state[level] = IN_BLOCK;
            state[--level] = END_BLOCK;
        }
        else if (!str_cmp (control, "else"))
        {
            if (!level || state[level - 1] != BEGIN_BLOCK)
            {
                sprintf (buf, "Mobprog: else without if, mob %d prog %d",
                         mvnum, pvnum);
                bug (buf, 0);
                return;
            }
            if (level && cond[level - 1] == FALSE)
                continue;
            state[level] = IN_BLOCK;
            cond[level] = (cond[level] == TRUE) ? FALSE : TRUE;
        }
        else if (cond[level] == TRUE
                 && (!str_cmp (control, "break")
                     || !str_cmp (control, "end")))
        {
            call_level--;
            return;
        }
        else if ((!level || cond[level] == TRUE) && buf[0] != '\0')
        {
            state[level] = IN_BLOCK;
            expand_arg (data, buf, mob, ch, arg1, arg2, rch);
            if (!str_cmp (control, "mob"))
            {
                /* 
                 * Found a mob restricted command, pass it to mob interpreter
                 */
                line = one_argument (data, control);
                mob_interpret (mob, line);
            }
            else
            {
                /* 
                 * Found a normal mud command, pass it to interpreter
                 */
                interpret (mob, data);
            }
        }
    }
    call_level--;
}

/* 
 * ---------------------------------------------------------------------
 * Trigger handlers. These are called from various parts of the code
 * when an event is triggered.
 * ---------------------------------------------------------------------
 */

/*
 * A general purpose string trigger. Matches argument to a string trigger
 * phrase.
 */
void mp_act_trigger (
                     char *argument, CHAR_DATA * mob, CHAR_DATA * ch,
                     const void *arg1, const void *arg2, int type)
{
    MPROG_LIST *prg;

    if (!IS_NPC(mob)) return;

    for (prg = mob->pIndexData->mprogs; prg != NULL; prg = prg->next)
    {
        if (prg->trig_type == type
            && strstr (argument, prg->trig_phrase) != NULL)
        {
            program_flow (prg->vnum, prg->code, mob, ch, arg1, arg2);
            break;
        }
    }
    return;
}

/*
 * A general purpose percentage trigger. Checks if a random percentage
 * number is less than trigger phrase
 */
bool mp_percent_trigger (CHAR_DATA * mob, CHAR_DATA * ch,
                         const void *arg1, const void *arg2, int type)
{
    MPROG_LIST *prg;

    for (prg = mob->pIndexData->mprogs; prg != NULL; prg = prg->next)
    {
        if (prg->trig_type == type
            && number_percent () < atoi (prg->trig_phrase))
        {
            program_flow (prg->vnum, prg->code, mob, ch, arg1, arg2);
            return (TRUE);
        }
    }
    return (FALSE);
}

void mp_bribe_trigger (CHAR_DATA * mob, CHAR_DATA * ch, int amount)
{
    MPROG_LIST *prg;

    /*
     * Original MERC 2.2 MOBprograms used to create a money object
     * and give it to the mobile. WFT was that? Funcs in act_obj()
     * handle it just fine.
     */
    for (prg = mob->pIndexData->mprogs; prg; prg = prg->next)
    {
        if (prg->trig_type == TRIG_BRIBE && amount >= atoi (prg->trig_phrase))
        {
            program_flow (prg->vnum, prg->code, mob, ch, NULL, NULL);
            break;
        }
    }
    return;
}

bool mp_exit_trigger (CHAR_DATA * ch, int dir)
{
    CHAR_DATA *mob;
    MPROG_LIST *prg;

    for (mob = ch->in_room->people; mob != NULL; mob = mob->next_in_room)
    {
        if (IS_NPC (mob)
            && (HAS_TRIGGER (mob, TRIG_EXIT)
                || HAS_TRIGGER (mob, TRIG_EXALL)))
        {
            for (prg = mob->pIndexData->mprogs; prg; prg = prg->next)
            {
                /*
                 * Exit trigger works only if the mobile is not busy
                 * (fighting etc.). If you want to be sure all players
                 * are caught, use ExAll trigger
                 */
                if (prg->trig_type == TRIG_EXIT
                    && dir == atoi (prg->trig_phrase)
                    && mob->position == mob->pIndexData->default_pos
                    && can_see (mob, ch))
                {
                    program_flow (prg->vnum, prg->code, mob, ch, NULL, NULL);
                    return TRUE;
                }
                else
                    if (prg->trig_type == TRIG_EXALL
                        && dir == atoi (prg->trig_phrase))
                {
                    program_flow (prg->vnum, prg->code, mob, ch, NULL, NULL);
                    return TRUE;
                }
            }
        }
    }
    return FALSE;
}

void mp_give_trigger (CHAR_DATA * mob, CHAR_DATA * ch, OBJ_DATA * obj)
{

    char buf[MAX_INPUT_LENGTH], *p;
    MPROG_LIST *prg;

    for (prg = mob->pIndexData->mprogs; prg; prg = prg->next)
        if (prg->trig_type == TRIG_GIVE)
        {
            p = prg->trig_phrase;
            /*
             * Vnum argument
             */
            if (is_number (p))
            {
                if (obj->pIndexData->vnum == atoi (p))
                {
                    program_flow (prg->vnum, prg->code, mob, ch, (void *) obj,
                                  NULL);
                    return;
                }
            }
            /*
             * Object name argument, e.g. 'sword'
             */
            else
            {
                while (*p)
                {
                    p = one_argument (p, buf);

                    if (is_name (buf, obj->name) || !str_cmp ("all", buf))
                    {
                        program_flow (prg->vnum, prg->code, mob, ch,
                                      (void *) obj, NULL);
                        return;
                    }
                }
            }
        }
}

void mp_greet_trigger (CHAR_DATA * ch)
{
    CHAR_DATA *mob;

    for (mob = ch->in_room->people; mob != NULL; mob = mob->next_in_room)
    {
        if (IS_NPC (mob)
            && (HAS_TRIGGER (mob, TRIG_GREET)
                || HAS_TRIGGER (mob, TRIG_GRALL)))
        {
            /*
             * Greet trigger works only if the mobile is not busy
             * (fighting etc.). If you want to catch all players, use
             * GrAll trigger
             */
            if (HAS_TRIGGER (mob, TRIG_GREET)
                && mob->position == mob->pIndexData->default_pos
                && can_see (mob, ch))
                mp_percent_trigger (mob, ch, NULL, NULL, TRIG_GREET);
            else if (HAS_TRIGGER (mob, TRIG_GRALL))
                mp_percent_trigger (mob, ch, NULL, NULL, TRIG_GRALL);
        }
    }
    return;
}

void mp_hprct_trigger (CHAR_DATA * mob, CHAR_DATA * ch)
{
    MPROG_LIST *prg;

    for (prg = mob->pIndexData->mprogs; prg != NULL; prg = prg->next)
        if ((prg->trig_type == TRIG_HPCNT)
            && ((100 * mob->hit / mob->max_hit) < atoi (prg->trig_phrase)))
        {
            program_flow (prg->vnum, prg->code, mob, ch, NULL, NULL);
            break;
        }
}

---