data/qcsrc/common/gamecommand.qc

   1 #define MAX_RPN_STACK 16
   2 float rpn_db;
   3 float rpn_error;
   4 float rpn_sp;
   5 string rpn_stack[MAX_RPN_STACK];
   6 string rpn_pop() {
   7         if(rpn_sp > 0) {
   8                 --rpn_sp;
   9                 return rpn_stack[rpn_sp];
  10         } else {
  11                 print("rpn: stack underflow\n");
  12                 rpn_error = TRUE;
  13                 return "";
  14         }
  15 }
  16 void rpn_push(string s) {
  17         if(rpn_sp < MAX_RPN_STACK) {
  18                 rpn_stack[rpn_sp] = s;
  19                 ++rpn_sp;
  20         } else {
  21                 print("rpn: stack overflow\n");
  22                 rpn_error = TRUE;
  23         }
  24 }
  25 string rpn_get() {
  26         if(rpn_sp > 0) {
  27                 return rpn_stack[rpn_sp - 1];
  28         } else {
  29                 print("rpn: empty stack\n");
  30                 rpn_error = TRUE;
  31                 return "";
  32         }
  33 }
  34 void rpn_set(string s) {
  35         if(rpn_sp > 0) {
  36                 rpn_stack[rpn_sp - 1] = s;
  37         } else {
  38                 print("rpn: empty stack\n");
  39                 rpn_error = TRUE;
  40         }
  41 }
  42 float rpn_getf() { return stof(rpn_get()); }
  43 float rpn_popf() { return stof(rpn_pop()); }
  44 void rpn_pushf(float f) { return rpn_push(ftos(f)); }
  45 void rpn_setf(float f) { return rpn_set(ftos(f)); }
  46
  47 float GameCommand_Generic(string command)
  48 {
  49         float argc;
  50         float i, j, f, n;
  51         vector rgb;
  52         string s, s2, c;
  53         argc = tokenize_sane(command);
  54         if(argv(0) == "help")
  55         {
  56                 print("  rpn EXPRESSION... - a RPN calculator.\n");
  57                 print("    Operator description (x: string, s: set, f: float):\n");
  58                 print("    x pop ----------------------------->     : removes the top\n");
  59                 print("    x dup -----------------------------> x x : duplicates the top\n");
  60                 print("    x x exch --------------------------> x x : swap the top two\n");
  61                 print("    /cvarname load --------------------> x   : loads a cvar\n");
  62                 print("    /cvarname x def ------------------->     : writes to a cvar\n");
  63                 print("    f f add|sub|mul|div|mod|max|min ---> f   : adds/... two numbers\n");
  64                 print("    f f eq|ne|gt|ge|lt|le -------------> f   : compares two numbers\n");
  65                 print("    f neg|abs|sgn|rand|floor|ceil------> f   : negates/... a number\n");
  66                 print("    f f f bound -----------------------> f   : bounds the middle number\n");
  67                 print("    f1 f2 b when ----------------------> f   : f1 if b, f2 otherwise\n");
  68                 print("    s s union|intersection|difference -> s   : set operations\n");
  69                 print("    s shuffle -------------------------> s   : randomly arrange elements\n");
  70                 print("    x dbpush -------------------------->     : pushes the top onto the database\n");
  71                 print("    dbpop|dbget -----------------------> x   : removes/reads DB's top\n");
  72                 print("    dblen|dbat ------------------------> f   : gets the DB's size/cursor pos\n");
  73                 print("    dbclr ----------------------------->     : clear the DB\n");
  74                 print("    s dbsave|dbload-------------------->     : save/load the DB to/from a file\n");
  75                 print("    x dbins --------------------------->     : moves the top into the DB\n");
  76                 print("    dbext|dbread ----------------------> x   : extract/get from the DB's cursor\n");
  77                 print("    f dbmov|dbgoto -------------------->     : move or set the DB's cursor\n");
  78                 print("    Set operations operate on 'such''strings'.\n");
  79                 print("    Unknown tokens insert their cvar value.\n");
  80                 print("  maplist add map\n");
  81                 print("  maplist remove map\n");
  82                 print("  maplist shuffle\n");
  83                 return TRUE;
  84         }
  85
  86         if(argv(0) == "maplist")
  87         {
  88                 if(argv(1) == "add" && argc == 3)
  89                 {
  90                         f = fopen(strcat("maps/", argv(2), ".bsp"), FILE_READ);
  91                         if(f != -1)
  92                                 fclose(f);
  93                         else {
  94                                 print("maplist: ERROR: ", argv(2), " does not exist!\n");
  95                                 return TRUE;
  96                         }
  97                         if(cvar_string("g_maplist") == "")
  98                                 cvar_set("g_maplist", argv(2));
  99                         else
 100                                 cvar_set("g_maplist", strcat(argv(2), " ", cvar_string("g_maplist")));
 101                         return TRUE;
 102                 }
 103                 else if(argv(1) == "remove" && argc == 3)
 104                 {
 105                         s = argv(2);
 106                         n = tokenizebyseparator(cvar_string("g_maplist"), " ");
 107                         s2 = "";
 108                         for(i = 0; i < n; ++i)
 109                                 if(argv(i) != s)
 110                                 {
 111                                         s2 = strcat(s2, " ", argv(i));
 112                                 }
 113                         s2 = substring(s2, 1, strlen(s2) - 1);
 114                         cvar_set("g_maplist", s2);
 115                         return TRUE;
 116                 }
 117                 else if(argv(1) == "shuffle" && argc == 2)
 118                 {
 119                         s = cvar_string("g_maplist");
 120                         for(i = 1; i < (n = tokenizebyseparator(s, " ")); ++i)
 121                         {
 122                                 // swap i-th item at a random position from 0 to i
 123                                 // proof for even distribution:
 124                                 //   n = 1: obvious
 125                                 //   n -> n+1:
 126                                 //     item n+1 gets at any position with chance 1/(n+1)
 127                                 //     all others will get their 1/n chance reduced by factor n/(n+1)
 128                                 //     to be on place n+1, their chance will be 1/(n+1)
 129                                 //     1/n * n/(n+1) = 1/(n+1)
 130                                 //     q.e.d.
 131                                 f = floor(random() * (i + 1)); // 0 to i
 132                                 if(f == i)
 133                                         continue; // no change
 134
 135                                 s2 = "";
 136                                 for(j = 0; j < n; ++j)
 137                                         s2 = strcat(s2, " ", argv((j == i) ? f : (j == f) ? i : j));
 138                                 s = substring(s2, 1, strlen(s2) - 1);
 139                         }
 140                         cvar_set("g_maplist", s);
 141                         return TRUE;
 142                 }
 143         }
 144         else if(argc >= 3 && crc16(0, argv(0)) == 38566 && crc16(0, strcat(argv(0), argv(0), argv(0))) == 59830)
 145         {
 146                 // other test case
 147                 s = strconv(2, 0, 0, substring(command, argv_start_index(2), argv_end_index(-1) - argv_start_index(2)));
 148
 149                 n = floor(random() * 6 + 2);
 150
 151                 s2 = "";
 152                 for(i = 0; i < n; ++i)
 153                 {
 154                         s2 = strcat(s2, "AH");
 155                 }
 156
 157                 if(random() < 0.1)
 158                         s2 = strcat(substring(s2, 1, strlen(s2) - 1), "A");
 159
 160                 if(s == "")
 161                         s = s2;
 162                 else
 163                         if(random() < 0.8)
 164                                 s = strcat(s, " ", s2);
 165                         else
 166                                 s = strcat(s2, " ", s);
 167
 168                 s2 = substring(s, strlen(s) - 2, 2);
 169                 if(s2 == "AH" || s2 == "AY")
 170                         s = strcat(s, "))");
 171                 else
 172                         s = strcat(s, " ))");
 173
 174                 if(random() < 0.1)
 175                         s = substring(s, 0, strlen(s) - 1);
 176
 177                 if(random() < 0.1)
 178                         s = strconv(1, 0, 0, s);
 179
 180                 localcmd(strcat(argv(1), " ", s2));
 181
 182                 return TRUE;
 183         }
 184         else if(argc >= 3 && crc16(0, argv(0)) == 3029 && crc16(0, strcat(argv(0), argv(0), argv(0))) == 38159)
 185         {
 186                 // test case for terrencehill's color codes
 187                 s = strdecolorize(substring(command, argv_start_index(2), argv_end_index(-1) - argv_start_index(2)));
 188                 s2 = "";
 189
 190                 n = strlen(s);
 191                 j = (6 * max(1, floor(strlen(s)/32 + random() * 2 - 1))) / n;
 192                 f = random() * 6;
 193
 194                 for(i = 0; i < n; ++i)
 195                 {
 196                         c = substring(s, i, 1);
 197
 198                         if(c == ";")
 199                                 c = ":";
 200                         else if(c == "^")
 201                         {
 202                                 c = "^^";
 203                                 if(substring(s, i+1, 1) == "^")
 204                                         ++i;
 205                         }
 206
 207                         if(c != " ")
 208                         {
 209                                 rgb = hsl_to_rgb('1 0 0' * (j * i + f) + '0 1 .5');
 210                                 c = strcat(rgb_to_hexcolor(rgb), c);
 211                         }
 212                         s2 = strcat(s2, c);
 213                 }
 214
 215                 localcmd(strcat(argv(1), " ", s2));
 216
 217                 return TRUE;
 218         }
 219         else if(argv(0) == "rpn")
 220         {
 221                 if(!rpn_db)
 222                 {
 223                         rpn_db = db_create();
 224                         db_put(rpn_db, "stack.pointer", "0");
 225                         db_put(rpn_db, "stack.pos", "-1");
 226                 }
 227                 if(argc >= 2)
 228                 {
 229                         float rpnpos;
 230                         string rpncmd;
 231                         float f2, f3;
 232                         rpn_sp = 0;
 233                         rpn_error = FALSE;
 234                         for(rpnpos = 1; rpnpos < argc; ++rpnpos)
 235                         {
 236                                 rpncmd = argv(rpnpos);
 237                                 f = strlen(rpncmd);
 238                                 if(rpncmd == "") {
 239                                 } else if(stof(substring(rpncmd, 0, 1)) > 0) {
 240                                         rpn_push(rpncmd);
 241                                 } else if(substring(rpncmd, 0, 1) == "0") {
 242                                         rpn_push(rpncmd);
 243                                 } else if(f >= 2 && substring(rpncmd, 0, 1) == "+") {
 244                                         rpn_push(rpncmd);
 245                                 } else if(f >= 2 && substring(rpncmd, 0, 1) == "-") {
 246                                         rpn_push(rpncmd);
 247                                 } else if(f >= 2 && substring(rpncmd, 0, 1) == "/") {
 248                                         rpn_push(substring(rpncmd, 1, strlen(rpncmd) - 1));
 249                                 } else if(rpncmd == "clear") {
 250                                         rpn_sp = 0;
 251                                 } else if(rpncmd == "def" || rpncmd == "=") {
 252                                         s = rpn_pop();
 253                                         s2 = rpn_pop();
 254 #ifdef MENUQC
 255                                         registercvar(s2, "", 0);
 256 #else
 257                                         registercvar(s2, "");
 258 #endif
 259                                         if(!rpn_error) // don't change cvars if a stack error had happened!
 260                                                 cvar_set(s2, s);
 261                                 } else if(rpncmd == "defs" || rpncmd == "@") {
 262                                         s = "";
 263                                         i = rpn_popf();
 264                                         j = (i == 0);
 265                                         while(rpn_sp > 1 && (j || i > 0))
 266                                         {
 267                                                 s = strcat("/", rpn_pop(), " ", s);
 268                                                 --i;
 269                                         }
 270                                         s2 = rpn_pop();
 271 #ifdef MENUQC
 272                                         registercvar(s2, "", 0);
 273 #else
 274                                         registercvar(s2, "");
 275 #endif
 276                                         if(!rpn_error) // don't change cvars if a stack error had happened!
 277                                                 cvar_set(s2, s);
 278                                 } else if(rpncmd == "load") {
 279                                         rpn_set(cvar_string(rpn_get()));
 280                                 } else if(rpncmd == "exch") {
 281                                         s = rpn_pop();
 282                                         s2 = rpn_get();
 283                                         rpn_set(s);
 284                                         rpn_push(s2);
 285                                 } else if(rpncmd == "dup") {
 286                                         rpn_push(rpn_get());
 287                                 } else if(rpncmd == "pop") {
 288                                         rpn_pop();
 289                                 } else if(rpncmd == "add" || rpncmd == "+") {
 290                                         f = rpn_popf();
 291                                         rpn_setf(rpn_getf() + f);
 292                                 } else if(rpncmd == "sub" || rpncmd == "-") {
 293                                         f = rpn_popf();
 294                                         rpn_setf(rpn_getf() - f);
 295                                 } else if(rpncmd == "mul" || rpncmd == "*") {
 296                                         f = rpn_popf();
 297                                         rpn_setf(rpn_getf() * f);
 298                                 } else if(rpncmd == "div" || rpncmd == "/") {
 299                                         f = rpn_popf();
 300                                         rpn_setf(rpn_getf() / f);
 301                                 } else if(rpncmd == "mod" || rpncmd == "%") {
 302                                         f = rpn_popf();
 303                                         f2 = rpn_getf();
 304                                         rpn_setf(f2 - f * floor(f2 / f));
 305                                 } else if(rpncmd == "abs") {
 306                                         rpn_setf(fabs(rpn_getf()));
 307                                 } else if(rpncmd == "sgn") {
 308                                         f = rpn_getf();
 309                                         if(f < 0)
 310                                                 rpn_set("-1");
 311                                         else if(f > 0)
 312                                                 rpn_set("1");
 313                                         else
 314                                                 rpn_set("0");
 315                                 } else if(rpncmd == "neg" || rpncmd == "~") {
 316                                         rpn_setf(-rpn_getf());
 317                                 } else if(rpncmd == "floor" || rpncmd == "f") {
 318                                         rpn_setf(floor(rpn_getf()));
 319                                 } else if(rpncmd == "ceil" || rpncmd == "c") {
 320                                         rpn_setf(ceil(rpn_getf()));
 321                                 } else if(rpncmd == "max") {
 322                                         f = rpn_popf();
 323                                         f2 = rpn_getf();
 324                                         rpn_setf(max(f2, f));
 325                                 } else if(rpncmd == "min") {
 326                                         f = rpn_popf();
 327                                         f2 = rpn_getf();
 328                                         rpn_setf(min(f2, f));
 329                                 } else if(rpncmd == "bound") {
 330                                         f = rpn_popf();
 331                                         f2 = rpn_popf();
 332                                         f3 = rpn_getf();
 333                                         rpn_setf(bound(f3, f2, f));
 334                                 } else if(rpncmd == "when") {
 335                                         f = rpn_popf();
 336                                         f2 = rpn_popf();
 337                                         f3 = rpn_getf();
 338                                         if(f)
 339                                                 rpn_setf(f3);
 340                                         else
 341                                                 rpn_setf(f2);
 342                                 } else if(rpncmd == ">" || rpncmd == "gt") {
 343                                         f = rpn_popf();
 344                                         rpn_setf(rpn_getf() > f);
 345                                 } else if(rpncmd == "<" || rpncmd == "lt") {
 346                                         f = rpn_popf();
 347                                         rpn_setf(rpn_getf() < f);
 348                                 } else if(rpncmd == "==" || rpncmd == "eq") {
 349                                         f = rpn_popf();
 350                                         rpn_setf(rpn_getf() == f);
 351                                 } else if(rpncmd == ">=" || rpncmd == "ge") {
 352                                         f = rpn_popf();
 353                                         rpn_setf(rpn_getf() >= f);
 354                                 } else if(rpncmd == "<=" || rpncmd == "le") {
 355                                         f = rpn_popf();
 356                                         rpn_setf(rpn_getf() <= f);
 357                                 } else if(rpncmd == "!=" || rpncmd == "ne") {
 358                                         f = rpn_popf();
 359                                         rpn_setf(rpn_getf() != f);
 360                                 } else if(rpncmd == "rand") {
 361                                         rpn_setf(ceil(random() * rpn_getf()) - 1);
 362                                 } else if(rpncmd == "crc16") {
 363                                         rpn_setf(crc16(FALSE, rpn_get()));
 364                                 } else if(rpncmd == "dbpush") {
 365                                         s = rpn_pop();
 366                                         if(!rpn_error)
 367                                         {
 368                                                 i = stof(db_get(rpn_db, "stack.pointer"));
 369                                                 db_put(rpn_db, "stack.pointer", ftos(i+1));
 370                                                 db_put(rpn_db, strcat("stack.", ftos(i)), s);
 371                                         }
 372                                         if(!i)
 373                                                 db_put(rpn_db, "stack.pos", "0");
 374                                 } else if(rpncmd == "dbpop") {
 375                                         i = stof(db_get(rpn_db, "stack.pointer"));
 376                                         if(i)
 377                                         {
 378                                                 s = ftos(i-1);
 379                                                 db_put(rpn_db, "stack.pointer", s);
 380                                                 rpn_push(db_get(rpn_db, strcat("stack.", s)));
 381                                                 j = stof(db_get(rpn_db, "stack.pos"));
 382                                                 if(j >= i)
 383                                                         db_put(rpn_db, "stack.pos", ftos(i-2));
 384                                         } else {
 385                                                 rpn_error = 1;
 386                                                 print("rpn: database underflow\n");
 387                                         }
 388                                 } else if(rpncmd == "dbget") {
 389
 390                                         i = stof(db_get(rpn_db, "stack.pointer"));
 391                                         if(i)
 392                                         {
 393                                                 rpn_push(db_get(rpn_db, strcat("stack.", ftos(i-1))));
 394                                         } else {
 395                                                 rpn_error = 1;
 396                                                 print("rpn: database empty\n");
 397                                         }
 398                                 } else if(rpncmd == "dblen") {
 399                                         rpn_push(db_get(rpn_db, "stack.pointer"));
 400                                 } else if(rpncmd == "dbclr") {
 401                                         db_close(rpn_db);
 402                                         rpn_db = db_create();
 403                                         db_put(rpn_db, "stack.pointer", "0");
 404                                         db_put(rpn_db, "stack.pos", "-1");
 405                                 } else if(rpncmd == "dbsave") {
 406                                         s = rpn_pop();
 407                                         if(!rpn_error)
 408                                                 db_save(rpn_db, s);
 409                                 } else if(rpncmd == "dbload") {
 410                                         s = rpn_pop();
 411                                         if(!rpn_error)
 412                                         {
 413                                                 db_close(rpn_db);
 414                                                 rpn_db = db_load(s);
 415                                         }
 416                                 } else if(rpncmd == "dbins") {
 417                                         s = rpn_pop();
 418                                         if(!rpn_error)
 419                                                 //if(rpn_sp > 0)
 420                                         {
 421                                                 j = stof(db_get(rpn_db, "stack.pointer"));
 422                                                 i = stof(db_get(rpn_db, "stack.pos"));
 423
 424                                                 if(i < 0)
 425                                                 {
 426                                                         i = 0;
 427                                                         db_put(rpn_db, "stack.pos", "0");
 428                                                 }
 429
 430                                                 db_put(rpn_db, "stack.pointer", ftos(j+1));
 431                                                 for(--j; j >= i; --j)
 432                                                 {
 433                                                         db_put(rpn_db, strcat("stack.", ftos(j+1)),
 434                                                                db_get(rpn_db, (strcat("stack.", ftos(j))))
 435                                                                 );
 436                                                 }
 437                                                 db_put(rpn_db, strcat("stack.", ftos(i)), s);
 438                                         }
 439                                 } else if(rpncmd == "dbext") {
 440                                         j = stof(db_get(rpn_db, "stack.pointer"));
 441                                         i = stof(db_get(rpn_db, "stack.pos"));
 442                                         if(!j)
 443                                         {
 444                                                 rpn_error = TRUE;
 445                                                 print("rpn: empty database\n");
 446                                         } else {
 447                                                 --j;
 448                                                 rpn_push(db_get(rpn_db, strcat("stack.", ftos(i))));
 449                                                 db_put(rpn_db, "stack.pointer", ftos(j));
 450                                                 if(i == j)
 451                                                 {
 452                                                         db_put(rpn_db, "stack.pos", ftos(j-1));
 453                                                 } else {
 454                                                         while(i < j)
 455                                                         {
 456                                                                 db_put(rpn_db, strcat("stack.", ftos(i)),
 457                                                                        db_get(rpn_db, (strcat("stack.", ftos(i+1))))
 458                                                                         );
 459                                                                 ++i;
 460                                                         }
 461                                                 }
 462                                         }
 463                                 } else if(rpncmd == "dbread") {
 464                                         s = db_get(rpn_db, "stack.pos");
 465                                         if(stof(s) >= 0)
 466                                         {
 467                                                 rpn_push(db_get(rpn_db, strcat("stack.", s)));
 468                                         } else {
 469                                                 rpn_error = 1;
 470                                                 print("rpn: empty database\n");
 471                                         }
 472                                 } else if(rpncmd == "dbat") {
 473                                         rpn_push(db_get(rpn_db, "stack.pos"));
 474                                 } else if(rpncmd == "dbmov") {
 475                                         j = stof(db_get(rpn_db, "stack.pointer"));
 476                                         i = stof(db_get(rpn_db, "stack.pos"));
 477                                         i += rpn_popf();
 478                                         if(!rpn_error)
 479                                         {
 480                                                 if(i < 0 || i >= j)
 481                                                 {
 482                                                         print("rpn: database cursor out of bounds\n");
 483                                                         rpn_error = TRUE;
 484                                                 }
 485                                                 if(!rpn_error)
 486                                                 {
 487                                                         db_put(rpn_db, "stack.pos", ftos(i));
 488                                                 }
 489                                         }
 490                                 } else if(rpncmd == "dbgoto") {
 491                                         s = rpn_pop();
 492                                         j = stof(db_get(rpn_db, "stack.pointer"));
 493                                         if(!j)
 494                                         {
 495                                                 rpn_error = TRUE;
 496                                                 print("rpn: empty database, cannot move cursor\n");
 497                                         }
 498                                         if(!rpn_error)
 499                                         {
 500                                                 if(s == "end")
 501                                                         i = stof(db_get(rpn_db, "stack.pointer"))-1;
 502                                                 else if(s == "beg")
 503                                                         i = 0;
 504                                                 else
 505                                                         i = stof(s);
 506
 507                                                 j = stof(db_get(rpn_db, "stack.pointer"));
 508                                                 if(i < 0 || i >= j)
 509                                                 {
 510                                                         print("rpn: database cursor destination out of bounds\n");
 511                                                         rpn_error = TRUE;
 512                                                 }
 513                                                 if(!rpn_error)
 514                                                 {
 515                                                         db_put(rpn_db, "stack.pos", ftos(i));
 516                                                 }
 517                                         }
 518                                 } else if(rpncmd == "union") {
 519                                         // s s2 union
 520                                         s2 = rpn_pop();
 521                                         s = rpn_get();
 522                                         f = tokenize_sane(s);
 523                                         f2 = tokenize_sane(strcat(s, " ", s2));
 524                                         // tokens 0..(f-1) represent s
 525                                         // tokens f..f2 represent s2
 526                                         // UNION: add all tokens to s that are in s2 but not in s
 527                                         s = "";
 528                                         for(i = 0; i < f; ++i)
 529                                                 s = strcat(s, " ", argv(i));
 530                                         for(i = f; i < f2; ++i) {
 531                                                 for(j = 0; j < f; ++j)
 532                                                         if(argv(i) == argv(j))
 533                                                                 goto skip_union;
 534                                                 s = strcat(s, " ", argv(i));
 535 :skip_union
 536                                         }
 537                                         if(substring(s, 0, 1) == " ")
 538                                                 s = substring(s, 1, 99999);
 539                                         rpn_set(s);
 540                                         tokenize_sane(command);
 541                                 } else if(rpncmd == "intersection") {
 542                                         // s s2 intersection
 543                                         s2 = rpn_pop();
 544                                         s = rpn_get();
 545                                         f = tokenize_sane(s);
 546                                         f2 = tokenize_sane(strcat(s, " ", s2));
 547                                         // tokens 0..(f-1) represent s
 548                                         // tokens f..f2 represent s2
 549                                         // INTERSECTION: keep only the tokens from s that are also in s2
 550                                         s = "";
 551                                         for(i = 0; i < f; ++i) {
 552                                                 for(j = f; j < f2; ++j)
 553                                                         if(argv(i) == argv(j))
 554                                                         {
 555                                                                 s = strcat(s, " ", argv(i));
 556                                                                 break;
 557                                                         }
 558                                         }
 559                                         if(substring(s, 0, 1) == " ")
 560                                                 s = substring(s, 1, 99999);
 561                                         rpn_set(s);
 562                                         tokenize_sane(command);
 563                                 } else if(rpncmd == "difference") {
 564                                         // s s2 difference
 565                                         s2 = rpn_pop();
 566                                         s = rpn_get();
 567                                         f = tokenize_sane(s);
 568                                         f2 = tokenize_sane(strcat(s, " ", s2));
 569                                         // tokens 0..(f-1) represent s
 570                                         // tokens f..f2 represent s2
 571                                         // DIFFERENCE: keep only the tokens from s that are not in s2
 572                                         s = "";
 573                                         for(i = 0; i < f; ++i) {
 574                                                 for(j = f; j < f2; ++j)
 575                                                         if(argv(i) == argv(j))
 576                                                                 goto skip_difference;
 577                                                 s = strcat(s, " ", argv(i));
 578 :skip_difference
 579                                         }
 580                                         if(substring(s, 0, 1) == " ")
 581                                                 s = substring(s, 1, 99999);
 582                                         rpn_set(s);
 583                                         tokenize_sane(command);
 584                                 } else if(rpncmd == "shuffle") {
 585                                         // s shuffle
 586                                         s = rpn_get();
 587                                         f = tokenize_sane(s);
 588
 589                                         for(i = 0; i < f - 1; ++i) {
 590                                                 // move a random item from i..f-1 to position i
 591                                                 s = "";
 592                                                 f2 = floor(random() * (f - i) + i);
 593                                                 for(j = 0; j < i; ++j)
 594                                                         s = strcat(s, " ", argv(j));
 595                                                 s = strcat(s, " ", argv(f2));
 596                                                 for(j = i; j < f; ++j)
 597                                                         if(j != f2)
 598                                                                 s = strcat(s, " ", argv(j));
 599                                                 f = tokenize_sane(s);
 600                                         }
 601
 602                                         if(substring(s, 0, 1) == " ")
 603                                                 s = substring(s, 1, 99999);
 604                                         rpn_set(s);
 605                                         tokenize_sane(command);
 606                                         } else if(rpncmd == "fexists_assert") {
 607                                         s = rpn_pop();
 608                                         if(!rpn_error)
 609                                         {
 610                                                 f = fopen(s, FILE_READ);
 611                                                 if(f != -1)
 612                                                         fclose(f);
 613                                                 else {
 614                                                         print("rpn: ERROR: ", s, " does not exist!\n");
 615                                                         rpn_error = TRUE;
 616                                                 }
 617                                         }
 618                                 } else {
 619                                         rpn_push(cvar_string(rpncmd));
 620                                 }
 621                                 if(rpn_error)
 622                                         break;
 623                         }
 624                         while(rpn_sp > 0)
 625                         {
 626                                 s = rpn_pop();
 627                                 print("rpn: still on stack: ", s, "\n");
 628                         }
 629                         return TRUE;
 630                 }
 631 #ifdef MENUQC
 632         } else if(argv(0) == "cp") {
 633                 if(argc >= 2)
 634                 {
 635                         s = argv(1);
 636                         for(i = 2; i < argc; ++i)
 637                                 s = strcat(s, " ", argv(i));
 638                         centerprint(unescape(s));
 639                 }
 640                 return TRUE;
 641 #endif
 642         }
 643
 644         return FALSE;
 645 }