parser.c

   1 #include <math.h>
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4 #include <string.h>
   5
   6 #include "alloc.h"
   7 #include "argument.h"
   8 #include "debug.h"
   9 #include "element.h"
  10 #include "format.h"
  11 #include "program.h"
  12 #include "stack.h"
  13 #include "storage.h"
  14
  15 #include "parser.h"
  16
  17 /* global variables */
  18
  19 double answer = 0;
  20
  21 /* compare codes */
  22
  23 int codecmp (char *ref, char *str)
  24 {
  25     int sig;
  26
  27     while (*ref != '\0') {
  28         if (*ref == '\t') {
  29              sig = (*str == '.') ? -1 : ((*str >= '0') && (*str <= '9'));
  30         } else {
  31             sig = *str - *ref;
  32         }
  33         if (sig != 0) {
  34             return (sig > 0) ? 1 : -1;
  35         }
  36         str++;
  37         ref++;
  38     }
  39
  40     return 0;
  41 }
  42
  43 /* functions */
  44
  45 #define MAX_ARGS 100
  46
  47 #define NB_OPERATORS 14
  48 keyword_t operators[NB_OPERATORS] = {
  49     { "+\t", Add, 2, 1, 1},
  50     { "-\t", Sub, 2, 1, 1},
  51     { "*",   Mul, 2, 1, 2},
  52     { "/",   Div, 2, 1, 2},
  53     { "%",   Mod, 2, 1, 3},
  54     { "^",   Pow, 2, 1, 4},
  55     { "==",  Equal, 2, 2, -1},
  56     { "!=",  Diff, 2, 2, -1},
  57     { ">=",  Ge, 2, 2, -1},
  58     { "<=",  Le, 2, 2, -1},
  59     { ">",   Gt, 2, 1, -1},
  60     { "<",   Lt, 2, 1, -1},
  61     { "&",   And, 2, 1, -2},
  62     { "|",   Or, 2, 1, -2}
  63 };
  64
  65 #define NB_FUNCTIONS 52
  66 keyword_t functions[NB_FUNCTIONS] = {
  67     { "sqrt", Sqr, 1, 4, 5},
  68     { "pow",  Pow, 2, 3, 5},
  69     { "cos",  Cos, 1, 3, 5},
  70     { "sin",  Sin, 1, 3, 5},
  71     { "tan",  Tan, 1, 3, 5},
  72     { "acos", Acos, 1, 4, 5},
  73     { "asin", Asin, 1, 4, 5},
  74     { "atan", Atan, 1, 4, 5},
  75     { "ln",   Ln, 1, 2, 5},
  76     { "log",  Log, 1, 3, 5},
  77     { "exp",  Exp, 1, 3, 5},
  78     { "erfc", Erfc, 1, 4, 5},
  79     { "erf",  Erf, 1, 3, 5},
  80     { "abs",  Abs, 1, 3, 5},
  81     { "floor", Floor, 1, 5, 5},
  82     { "ceil", Ceil, 1, 4, 5},
  83     { "sto",  Store, 2, 3, 5},
  84     { "rcl",  Recall, 1, 3, 5},
  85     { "inc",  Inc, 1, 3, 5},
  86     { "dec",  Dec, 1, 3, 5},
  87     { "disp", Disp, 0, 4, 9},
  88     { "mem",  Memory, 1, 3, 5},
  89     { "clr",  Clear, 0, 3, 9},
  90     { "quit", Quit, 0, 4, 9},
  91     { "help", Help, 0, 4, 9},
  92     { "!",    Not, 1, 1, 6},
  93     { "cond", Cond, 3, 4, 5},
  94     { "while", While, 2, 5, 5},
  95     { "print", Print, 1, 5, 5},
  96     { "prog", Prog, 2, 4, 9},
  97     { "arg",  Arg, 1, 3, 5},
  98     { "call", Call, MAX_ARGS, 4, 5},
  99     { "ls",   List, 0, 2, 9},
 100     { "edit", Edit, 1, 4, 9},
 101     { "del",  Del, 1, 3, 9},
 102     { "get",  Get, 1, 3, 5},
 103     { "len",  Length, 0, 3, 5},
 104     { "pop",  Pop, 0, 3, 5},
 105     { "push", Push, 1, 4, 5},
 106     { "put",  Put, 2, 3, 5},
 107     { "set",  Set, MAX_ARGS, 3, 5},
 108     { "show", Show, 0, 4, 5},
 109     { "max",  Max, 2, 3, 5},
 110     { "mean", Mean, 2, 4, 5},
 111     { "med",  Median, 0, 3, 5},
 112     { "min",  Min, 2, 3, 5},
 113     { "ord",  Order, 0, 3, 5},
 114     { "prod", Prod, 0, 4, 5},
 115     { "sum",  Sum, 0, 3, 5},
 116     { "var",  Variance, 2, 3, 5},
 117     { "format", Precision, 1, 6, 9},
 118     { "base", Base, 2, 4, 9}
 119 };
 120
 121 #define NB_CONSTANTS 3
 122 keyword_t constants[NB_CONSTANTS] = {
 123     { "ans", Ans, 0, 3, 5},
 124     { "e",   E, 0, 1, 5},
 125     { "pi",  Pi, 0, 2, 5}
 126 };
 127
 128 #define NB_SYMBOLS 4
 129 char *symbols[NB_SYMBOLS] = {
 130     "(", ")", "{", "}"
 131 };
 132
 133 /* subparser function */
 134
 135 element_t *subparser (element_t **proot, char **pstr, func_t func, int nbops, int prio)
 136 {
 137     element_t *new = newelement (func, nbops, prio);
 138     new->ops[0] = *proot;
 139     new->ops[1] = parser (*pstr, pstr, new->prio);
 140     if ((new->ops[1] == NULL) || ((new->ops[1] != ERROR_OP) && (new->ops[1]->prio == 9))) {
 141         delelement (new->ops[1]);
 142         new->ops[1] = ERROR_OP;
 143     }
 144     if (new->ops[1] == ERROR_OP) {
 145         delelement (new);
 146         *proot = NULL;
 147         return ERROR_OP;
 148     }
 149     *proot = newelement (Val, 1, 5);
 150     (*proot)->ops[0] = new;
 151
 152     return *proot;
 153 }
 154
 155 /* parser function */
 156
 157 element_t *parser (char *str, char **next, int prio)
 158 {
 159     element_t *root = NULL;
 160     char *string = str;
 161     int i;
 162
 163     VERBOSE (DEBUG, fprintf (stdout, "Starting parsing\n"));
 164
 165     /* main loop */
 166     while (*str != '\0') {
 167         int found = 0;
 168         element_t *new = NULL;
 169         VERBOSE (INFO, fprintf (stdout, "Processing: %s\n", str));
 170
 171         /* end without printing */
 172
 173         if (*str == ';') {
 174             if (root) {
 175                 root->hidden = 1;
 176             }
 177             break;
 178         }
 179
 180         /* skip spaces and tabs */
 181
 182         if ((*str == ' ') || (*str == '\t')) {
 183             str++;
 184             continue;
 185         }
 186
 187         /* check for open brace */
 188
 189         if (*str == '{') {
 190             VERBOSE (DEBUG, fprintf (stdout, "start processing brace\n"));
 191             if (root != NULL) {
 192                 delelement (root);
 193                 return ERROR_OP;
 194             }
 195             root = newelement (Code, 0, 5);
 196
 197             do {
 198                 new = parser (str + 1, &str, 0);
 199                 if ((new == NULL) || ((new != ERROR_OP) && (new->prio == 9))) {
 200                     delelement (new);
 201                     new = ERROR_OP;
 202                 }
 203                 if (new == ERROR_OP) {
 204                     delelement (root);
 205                     return ERROR_OP;
 206                 }
 207                 element_t *newcode = newelement (Code, root->nbops + 1, 5);
 208                 for (i = 0; i < root->nbops; i++) {
 209                     newcode->ops[i] = root->ops[i];
 210                     root->ops[i] = NULL;
 211                 }
 212                 newcode->ops[root->nbops] = new;
 213                 delelement (root);
 214                 root = newcode;
 215             } while (*str == ',');
 216
 217             if (*str != '}') {
 218                 delelement (root);
 219                 return ERROR_OP;
 220             }
 221             str++;
 222             VERBOSE (DEBUG, fprintf (stdout, "stop processing brace\n"));
 223             continue;
 224         }
 225
 226         /* check for open bracket */
 227
 228         if (*str == '(') {
 229             VERBOSE (DEBUG, fprintf (stdout, "start processing bracket\n"));
 230             if (root) {
 231                 do {
 232                     found = 0;
 233                     new = parser (str + 1, &str, 0);
 234                     if ((new == NULL) || ((new != ERROR_OP) && (new->prio == 9))) {
 235                         delelement (new);
 236                         new = ERROR_OP;
 237                     }
 238                     if ((new == NULL) || (new == ERROR_OP)) {
 239                         delelement (root);
 240                         return ERROR_OP;
 241                     }
 242                     for (i = 0; i < root->nbops; i++) {
 243                         if (root->ops[i] == NULL) {
 244                             root->ops[i] = new;
 245                             found = 1;
 246                             break;
 247                         }
 248                     }
 249                     if (!found) {
 250                         delelement (new);
 251                         delelement (root);
 252                         return ERROR_OP;
 253                     }
 254                 } while (*str == ',');
 255             } else {
 256                 root = newelement (Val, 1, 5);
 257                 new = parser (str + 1, &str, 0);
 258                 if ((new == NULL) || ((new != ERROR_OP) && (new->prio == 9))) {
 259                     delelement (new);
 260                     new = ERROR_OP;
 261                 }
 262                 if ((new == NULL) || (new == ERROR_OP) || (*str == ',')) {
 263                     delelement (new);
 264                     delelement (root);
 265                     return ERROR_OP;
 266                 }
 267                 root->ops[0] = new;
 268             }
 269             if (*str != ')') {
 270                 delelement (root);
 271                 return ERROR_OP;
 272             }
 273             str++;
 274             VERBOSE (DEBUG, fprintf (stdout, "stop processing bracket\n"));
 275             continue;
 276         }
 277
 278         /* check for closing bracket, closing brace or koma */
 279
 280         if ((*str == ')') || (*str == '}') || (*str == ',')) {
 281             if (prio == -9) {
 282                 delelement (root);
 283                 return ERROR_OP;
 284             }
 285             if (next != NULL) {
 286                 *next = str;
 287             }
 288             return root;
 289         }
 290
 291         /* look for operators */
 292
 293         for (i = 0; i < NB_OPERATORS; i++) {
 294             keyword_t *operator = operators + i;
 295             if (codecmp (operator->keyword, str) == 0) {
 296                 VERBOSE (DEBUG, fprintf (stdout, "start processing operator\n"));
 297                 if ((root) && (root->prio == 9)) {
 298                     VERBOSE (DEBUG, fprintf (stdout, "terminal function (%d)\n", root->func));
 299                     delelement (root);
 300                     return ERROR_OP;
 301                 } else if (root) {
 302                     if ((prio) && (prio > operator->prio)) {
 303                         VERBOSE (DEBUG, fprintf (stdout, "stop because operator priority\n"));
 304                         *next = str;
 305                         return root;
 306                     }
 307                     str += operator->offset;
 308                     VERBOSE (INFO, fprintf (stdout, "Oper: %d\n", operator->func));
 309                     if (subparser (&root, &str, operator->func, operator->nbops, operator->prio) == ERROR_OP) {
 310                         delelement (root);
 311                         return ERROR_OP;
 312                     }
 313                 } else if (*str == '-') {
 314                     root = newelement (Sig, 1, 6);
 315                 } else {
 316                     return ERROR_OP;
 317                 }
 318                 found = 1;
 319                 VERBOSE (DEBUG, fprintf (stdout, "stop processing operator\n"));
 320                 break;
 321             }
 322         }
 323         if (found) {
 324             continue;
 325         }
 326
 327         /* look for functions */
 328
 329         for (i = 0; i < NB_FUNCTIONS; i++) {
 330             keyword_t *function = functions + i;
 331             if (codecmp (function->keyword, str) == 0) {
 332                 VERBOSE (DEBUG, fprintf (stdout, "start processing function\n"));
 333                 if (root == NULL) {
 334                     VERBOSE (INFO, fprintf (stdout, "Func: %d\n", function->func));
 335                     root = newelement (function->func, function->nbops, function->prio);
 336                 } else {
 337                     delelement (root);
 338                     return ERROR_OP;
 339                 }
 340                 str += function->offset;
 341                 found = 1;
 342                 VERBOSE (DEBUG, fprintf (stdout, "stop processing function\n"));
 343                 break;
 344             }
 345         }
 346         if (found) {
 347             continue;
 348         }
 349
 350         /* look for constant */
 351
 352         for (i = 0; i < NB_CONSTANTS; i++) {
 353             keyword_t *constant = constants + i;
 354             if (codecmp (constant->keyword, str) == 0) {
 355                 VERBOSE (DEBUG, fprintf (stdout, "start processing constant\n"));
 356                 if (root == NULL) {
 357                     VERBOSE (INFO, fprintf (stdout, "Const: %d\n", constant->func));
 358                     root = newelement (constant->func, constant->nbops, constant->prio);
 359                 } else {
 360                     delelement (root);
 361                     return ERROR_OP;
 362                 }
 363                 str += constant->offset;
 364                 found = 1;
 365                 VERBOSE (DEBUG, fprintf (stdout, "stop processing constant\n"));
 366                 break;
 367             }
 368         }
 369         if (found) {
 370             continue;
 371         }
 372
 373         /* look for number */
 374
 375         VERBOSE (DEBUG, fprintf (stdout, "start processing value\n"));
 376         char *pt;
 377         double value = (get_ibase () == 10) ? strtod (str, &pt) : strtoul (str, &pt, get_ibase ());
 378         VERBOSE (INFO, fprintf (stdout, "Value: %f\n", value));
 379         if (str != pt) {
 380             if ((root == NULL) || (root->prio == 6)) {
 381                 new = newelement (Val, 1, 5);
 382                 new->value = value;
 383                 if (root == NULL) {
 384                     root = new;
 385                 } else {
 386                     for (i = 0; i < root->nbops; i++) {
 387                         if (root->ops[i] == NULL) {
 388                             root->ops[i] = new;
 389                             found = 1;
 390                             break;
 391                         }
 392                     }
 393                     if (!found) {
 394                         delelement (new);
 395                         delelement (root);
 396                         return ERROR_OP;
 397                     }
 398                 }
 399                 str = pt;
 400             } else if ((*str == '+') || (*str == '-')) {
 401                 if ((prio) && (prio > 1)) {
 402                     VERBOSE (DEBUG, fprintf (stdout, "stop because operator priority\n"));
 403                     *next = str;
 404                     return root;
 405                 }
 406                 if (subparser (&root, &str, Add, 2, 1) == ERROR_OP) {
 407                     delelement (root);
 408                     return ERROR_OP;
 409                 }
 410             } else {
 411                 delelement (root);
 412                 return ERROR_OP;
 413             }
 414             found = 1;
 415         }
 416         VERBOSE (DEBUG, fprintf (stdout, "stop processing value\n"));
 417
 418         /* error */
 419
 420         if (!found) {
 421             delelement (root);
 422             return ERROR_OP;
 423         }
 424
 425     }
 426
 427     if (next != NULL) {
 428         *next = str;
 429     }
 430
 431     /* save string */
 432     if (root != NULL) {
 433         root->string = string;
 434     }
 435
 436     return root;
 437 }
 438
 439 /* print element tree */
 440
 441 void print_element (element_t *root, int level)
 442 {
 443     char *func = NULL;
 444     int i;
 445
 446     if ((root == NULL) || (root == ERROR_OP)) {
 447         return;
 448     }
 449
 450     for (i = 0; i < level; i++) {
 451         fprintf (stdout, " ");
 452     }
 453
 454     switch (root->func) {
 455     case Val: func = "Value"; break;
 456     case Sig: func = "Sign"; break;
 457     case Add: func = "Addition"; break;
 458     case Sub: func = "Subtraction"; break;
 459     case Mul: func = "Multiplication"; break;
 460     case Div: func = "Division"; break;
 461     case Mod: func = "Modulo"; break;
 462     case Pow: func = "Power"; break;
 463     case Sqr: func = "Square Root"; break;
 464     case Cos: func = "Cosine"; break;
 465     case Sin: func = "Sine"; break;
 466     case Tan: func = "Tangent"; break;
 467     case Acos: func = "Arc Cosine"; break;
 468     case Asin: func = "Arc Sine"; break;
 469     case Atan: func = "Arc Tangent"; break;
 470     case Ln: func = "Logarithm (natural)"; break;
 471     case Log: func = "Logarithm (10 base)"; break;
 472     case Exp: func = "Exponantial"; break;
 473     case Erfc: func = "Complementary Error Function"; break;
 474     case Erf: func = "Error Function"; break;
 475     case Abs: func = "Absolute value"; break;
 476     case Ceil: func = "Ceil value"; break;
 477     case Floor: func = "Floor value"; break;
 478     case Store: func = "Store"; break;
 479     case Recall: func = "Recall"; break;
 480     case Inc: func = "Increase"; break;
 481     case Dec: func = "Decrease"; break;
 482     case Disp: func = "Display"; break;
 483     case Memory: func = "Memory"; break;
 484     case Clear: func = "Clear"; break;
 485     case Quit: func = "Quit"; break;
 486     case Help: func = "Help"; break;
 487     case Ans: func = "Ans"; break;
 488     case Pi: func = "Pi"; break;
 489     case E: func = "E"; break;
 490     case Equal: func = "Equal"; break;
 491     case Diff: func = "Different"; break;
 492     case Ge: func = "Greater or equal"; break;
 493     case Le: func = "Lesser or equal"; break;
 494     case Gt: func = "Greater"; break;
 495     case Lt: func = "Lesser"; break;
 496     case And: func = "And"; break;
 497     case Or: func = "Or"; break;
 498     case Not: func = "Not"; break;
 499     case Cond: func = "Condition"; break;
 500     case While: func = "While"; break;
 501     case Code: func = "Code"; break;
 502     case Print: func = "Print"; break;
 503     case Prog: func = "Program"; break;
 504     case Arg: func = "Argument"; break;
 505     case Call: func = "Call"; break;
 506     case List: func = "List"; break;
 507     case Edit: func = "Edit"; break;
 508     case Del: func = "Del"; break;
 509     case Get: func = "Get"; break;
 510     case Length: func = "Length"; break;
 511     case Pop: func = "Pop"; break;
 512     case Push: func = "Push"; break;
 513     case Put: func = "Put"; break;
 514     case Set: func = "Set"; break;
 515     case Show: func = "Show"; break;
 516     case Max: func = "Maximum"; break;
 517     case Mean: func = "Mean"; break;
 518     case Median: func = "Median"; break;
 519     case Min: func = "Minimum"; break;
 520     case Order: func = "Order"; break;
 521     case Prod: func = "Product"; break;
 522     case Sum: func = "Sum"; break;
 523     case Variance: func = "Variance"; break;
 524     case Precision: func = "Precision"; break;
 525     case Base: func = "Base"; break;
 526     }
 527
 528     fprintf (stdout, "Function: %s\n", func);
 529
 530     if ((root->func == Val) && (root->ops[0] == NULL)) {
 531         for (i = 0; i < level; i++) {
 532             fprintf (stdout, " ");
 533         }
 534         fprintf (stdout, "value: %f\n", root->value);
 535     } else {
 536         for (i = 0; i < root->nbops; i++) {
 537             print_element (root->ops[i], level + 1);
 538         }
 539     }
 540 }
 541
 542 /* While do function */
 543
 544 double while_do (element_t *cond, element_t *action)
 545 {
 546     double ret = 0;
 547     element_t *temp = NULL;
 548
 549     VERBOSE (DEBUG, fprintf (stdout, "starting while loop\n"));
 550     while (1) {
 551         VERBOSE (DEBUG, fprintf (stdout, "loop...\n"));
 552
 553         temp = dupelement (cond);
 554         double test = evaluate_element (temp, 0);
 555         delelement (temp);
 556         if (!test) {
 557             break;
 558         }
 559         if (action) {
 560             temp = dupelement (action);
 561             ret = evaluate_element (temp, 0);
 562             delelement (temp);
 563         }
 564     }
 565
 566     VERBOSE (DEBUG, fprintf (stdout, "ending while loop\n"));
 567
 568     return ret;
 569 }
 570
 571 /* program function */
 572
 573 double execute_code (element_t **prog, int nbcalls)
 574 {
 575     double ret = 0;
 576     int i;
 577     for (i = 0; i < nbcalls; i++) {
 578         ret = evaluate_element (prog[i], 0);
 579     }
 580     return ret;
 581 }
 582
 583 /* quit function */
 584
 585 void quit (void)
 586 {
 587     fprintf (stdout, "bye\n");
 588     exit (0);
 589 }
 590
 591 /* help message */
 592
 593 void help (void)
 594 {
 595     fprintf (stdout, "calc is a simple calculator\n\n");
 596     fprintf (stdout, "arithmetic op.:");
 597     fprintf (stdout, " + - * / %% ^\n");
 598     fprintf (stdout, "comparison op.:");
 599     fprintf (stdout, " == != >= <= > <\n");
 600     fprintf (stdout, "logical op.:");
 601     fprintf (stdout, " & | !\n");
 602     fprintf (stdout, "mathematic func.:");
 603     fprintf (stdout, " exp ln log pow sqrt\n");
 604     fprintf (stdout, "trigonometric func.:");
 605     fprintf (stdout, " acos asin atan cos sin tan\n");
 606     fprintf (stdout, "error functions:");
 607     fprintf (stdout, " erf erfc\n");
 608     fprintf (stdout, "miscellaneous func.:");
 609     fprintf (stdout, " abs ceil floor\n");
 610     fprintf (stdout, "storage func.:");
 611     fprintf (stdout, " clear dec disp inc mem rcl sto\n");
 612     fprintf (stdout, "control flow prim.:");
 613     fprintf (stdout, " cond print while {} ;\n");
 614     fprintf (stdout, "program management:");
 615     fprintf (stdout, " arg call del edit ls prog\n");
 616     fprintf (stdout, "stack management:");
 617     fprintf (stdout, " get len pop push put set show\n");
 618     fprintf (stdout, "stack func.:");
 619     fprintf (stdout, " max mean med min ord prod sum var\n");
 620     fprintf (stdout, "control management:");
 621     fprintf (stdout, " base format help quit\n");
 622     fprintf (stdout, "constants:");
 623     fprintf (stdout, " ans e pi\n");
 624 }
 625
 626 /* format function */
 627
 628 int format (int precision)
 629 {
 630     if (precision > 0) {
 631         set_precision (precision);
 632         set_format ();
 633     } else if (precision != -1) {
 634         VERBOSE (WARNING, fprintf (stdout, "error incorrect precision (%d)\n", precision));
 635         return 0;
 636     }
 637     return get_precision ();
 638 }
 639
 640 /* base function */
 641
 642 void base (int in, int out)
 643 {
 644     if (in > 0) {
 645         set_base (in, in);
 646         if (out > 0) {
 647             set_base (in, out);
 648         } else if (out != - 1) {
 649             VERBOSE (WARNING, fprintf (stdout, "error incorrect output base (%d)\n", out));
 650         }
 651     } else if (in != -1 ) {
 652         VERBOSE (WARNING, fprintf (stdout, "error incorrect input base (%d)\n", in));
 653     } else {
 654         printf ("base (I/O): %s\n", show_base ());
 655     }
 656 }
 657
 658 /* evaluate element tree */
 659
 660 #define MASK_SUB 0x1
 661 #define MASK_DIV 0x2
 662
 663 double evaluate_element (element_t *root, char mask)
 664 {
 665     double op0 = 0, op1 = 0;
 666     char nextmask = mask;
 667     int i, nb;
 668
 669     if ((root == NULL) || (root == ERROR_OP)) {
 670         VERBOSE (WARNING, fprintf (stdout, "error while evaluating\n"));
 671         return 0;
 672     }
 673
 674     /* mask to manage sub operator sub and div */
 675     switch (root->func) {
 676     case Add:
 677         nextmask &= ~MASK_SUB;
 678         nextmask &= ~MASK_DIV;
 679         break;
 680     case Sub:
 681         nextmask |= MASK_SUB;
 682         nextmask &= ~MASK_DIV;
 683         break;
 684     case Mul:
 685         nextmask &= ~MASK_DIV;
 686         break;
 687     case Div:
 688         nextmask |= MASK_DIV;
 689         break;
 690     default:
 691         nextmask = mask;
 692     }
 693
 694     switch (root->func) {
 695     case Val:
 696     case Sig:
 697         op0 = (root->ops[0]) ? evaluate_element (root->ops[0], nextmask) : root->value;
 698         break;
 699     case Add:
 700     case Sub:
 701     case Mul:
 702     case Div:
 703     case Mod:
 704     case Pow:
 705     case Equal:
 706     case Diff:
 707     case Ge:
 708     case Le:
 709     case Gt:
 710     case Lt:
 711     case And:
 712     case Or:
 713         if (root->ops[1]) {
 714             op1 = evaluate_element (root->ops[1], nextmask);
 715         } else {
 716             VERBOSE (WARNING, fprintf (stdout, "error while evaluating (op[1])\n"));
 717             return 0;
 718         }
 719         /* fallthrough */
 720     case Sqr:
 721     case Cos:
 722     case Sin:
 723     case Tan:
 724     case Acos:
 725     case Asin:
 726     case Atan:
 727     case Ln:
 728     case Log:
 729     case Exp:
 730     case Erfc:
 731     case Erf:
 732     case Abs:
 733     case Ceil:
 734     case Floor:
 735     case Recall:
 736     case Inc:
 737     case Dec:
 738     case Not:
 739     case Cond:
 740     case Prog:
 741     case Arg:
 742     case Call:
 743     case Edit:
 744     case Del:
 745     case Get:
 746         if (root->ops[0]) {
 747             op0 = evaluate_element (root->ops[0], 0);
 748         } else {
 749             VERBOSE (WARNING, fprintf (stdout, "error while evaluating (op[0])\n"));
 750             return 0;
 751         }
 752         break;
 753     case Disp:
 754     case Clear:
 755     case Quit:
 756     case Help:
 757     case Ans:
 758     case Pi:
 759     case E:
 760     case Code:
 761     case List:
 762     case Length:
 763     case Pop:
 764     case Set:
 765     case Show:
 766     case Median:
 767     case Order:
 768     case Prod:
 769     case Sum:
 770         break;
 771     case While:
 772         if (root->ops[0] == NULL) {
 773             VERBOSE (WARNING, fprintf (stdout, "error while evaluating (op[0])\n"));
 774             return 0;
 775         }
 776         break;
 777     case Memory:
 778         if (root->ops[0] == NULL) {
 779             op0 = -1;
 780         } else {
 781             op0 = (int)evaluate_element (root->ops[0], 0);
 782             if (op0 < 0) {
 783                 VERBOSE (WARNING, fprintf (stdout, "error incorrect memory size (%d)\n", (int)op0));
 784                 return 0;
 785             }
 786         }
 787         break;
 788     case Push:
 789     case Print:
 790         op0 = (root->ops[0]) ? evaluate_element (root->ops[0], 0) : answer;
 791         break;
 792     case Store:
 793     case Put:
 794         if (root->ops[0]) {
 795             op0 = evaluate_element (root->ops[0], 0);
 796         } else {
 797             VERBOSE (WARNING, fprintf (stdout, "error while evaluating (op[0])\n"));
 798             return 0;
 799         }
 800         op1 = (root->ops[1]) ? evaluate_element (root->ops[1], 0) : answer;
 801         break;
 802     case Max:
 803     case Mean:
 804     case Min:
 805     case Variance:
 806         if (root->ops[0]) {
 807             op0 = evaluate_element (root->ops[0], 0);
 808             op1 = (root->ops[1]) ? evaluate_element (root->ops[1], 0) : answer;
 809         }
 810         break;
 811     case Precision:
 812         op0 = (root->ops[0]) ? evaluate_element (root->ops[0], 0) : -1;
 813         break;
 814     case Base:
 815         op0 = (root->ops[0]) ? evaluate_element (root->ops[0], 0) : -1;
 816         op1 = (root->ops[1]) ? evaluate_element (root->ops[1], 0) : -1;
 817         break;
 818     }
 819
 820     switch (root->func) {
 821     case Val: return op0;
 822     case Sig: return -op0;
 823     case Add: return ((mask & MASK_SUB) == 0) ? op0 + op1 : op0 - op1;
 824     case Sub: return ((mask & MASK_SUB) == 0) ? op0 - op1 : op0 + op1;
 825     case Mul: return ((mask & MASK_DIV) == 0) ? op0 * op1 : op0 / op1;
 826     case Div: return ((mask & MASK_DIV) == 0) ? op0 / op1 : op0 * op1;
 827     case Mod: return fmod (op0, op1);
 828     case Pow: return pow (op0, op1);
 829     case Sqr: return sqrt (op0);
 830     case Cos: return cos (op0);
 831     case Sin: return sin (op0);
 832     case Tan: return tan (op0);
 833     case Acos: return acos (op0);
 834     case Asin: return asin (op0);
 835     case Atan: return atan (op0);
 836     case Ln: return log (op0);
 837     case Log: return log10 (op0);
 838     case Exp: return exp (op0);
 839     case Erfc: return erfc (op0);
 840     case Erf: return erf (op0);
 841     case Abs: return fabs (op0);
 842     case Ceil: return ceil (op0);
 843     case Floor: return floor (op0);
 844     case Store: return store ((int)op0, op1);
 845     case Recall: return recall ((int)op0);
 846     case Inc: return increase ((int)op0);
 847     case Dec: return decrease ((int)op0);
 848     case Disp: display (); break;
 849     case Memory: return memory ((root->ops[0]) ? (int)op0 : -1);
 850     case Clear: clear (); break;
 851     case Quit: quit (); break;
 852     case Help: help (); break;
 853     case Ans: return answer;
 854     case Pi: return M_PI;
 855     case E: return M_E;
 856     case Equal: return op0 == op1;
 857     case Diff: return op0 != op1;
 858     case Ge: return op0 >= op1;
 859     case Le: return op0 <= op1;
 860     case Gt: return op0 > op1;
 861     case Lt: return op0 < op1;
 862     case And: return (op0 != 0) && (op1 != 0);
 863     case Or: return (op0 != 0) || (op1 != 0);
 864     case Not: return (op0 == 0);
 865     case Cond:
 866         if ((op0) && (root->ops[1])) {
 867             return evaluate_element (root->ops[1], 0);
 868         } else if ((!op0) && (root->ops[2])) {
 869             return evaluate_element (root->ops[2], 0);
 870         } else {
 871             return 0;
 872         }
 873     case While: return while_do (root->ops[0], root->ops[1]);
 874     case Code: return execute_code (root->ops, root->nbops);
 875     case Print: return print (op0);
 876     case Prog:
 877         prog ((int)op0, root->ops[1]);
 878         savestring ((int)op0, root->string);
 879         break;
 880     case Arg: return arg ((int)op0);
 881     case Call:
 882         for (i = 1, nb = 0; i < root->nbops; i++) {
 883             if (root->ops[i]) {
 884                 nb++;
 885             }
 886         }
 887         return call ((int)op0, nb, root->ops + 1);
 888     case List: list (); break;
 889     case Edit: edit ((int)op0); break;
 890     case Del: del ((int)op0); break;
 891     case Get: return get ((int)op0);
 892     case Length: return length ();
 893     case Pop: return pop ();
 894     case Push: return push (op0);
 895     case Put: return put ((int)op0, op1);
 896     case Set:
 897         for (i = 0, nb =0; i < root->nbops; i++) {
 898             if (root->ops[i]) {
 899                 nb++;
 900             }
 901         }
 902         return set (nb, root->ops);
 903     case Show: show (); break;
 904     case Max:
 905         if (root->ops[0]) {
 906             return op0 > op1 ? op0 : op1;
 907         }
 908         return max ();
 909     case Mean:
 910         if (root->ops[0]) {
 911             return (op0 + op1) / 2;
 912         }
 913         return mean ();
 914     case Median: return median ();
 915     case Min:
 916         if (root->ops[0]) {
 917             return op0 < op1 ? op0 : op1;
 918         }
 919         return min ();
 920     case Order: order (); break;
 921     case Prod: return prod ();
 922     case Sum: return sum ();
 923     case Variance:
 924         if (root->ops[0]) {
 925             double m = (op0 + op1) / 2;
 926             op0 -= m;
 927             op1 -= m;
 928             return op0 * op0 + op1 * op1;
 929         }
 930         return variance ();
 931     case Precision:
 932         return format ((int)op0);
 933     case Base:
 934         base (op0, op1);
 935         break;
 936     }
 937
 938     return 0;
 939 }
 940
 941 char **generate_completion_list ()
 942 {
 943     int i, j, l = 0;
 944     char **list = (char **) callocordie (NB_OPERATORS + NB_FUNCTIONS + NB_CONSTANTS + NB_SYMBOLS + 1, sizeof (char *));
 945
 946     for (i = 0; i < NB_OPERATORS; i++) {
 947         list[l] = strdup ((operators + i)->keyword);
 948         for (j = 0; j < (int)strlen (list[l]); j++) {
 949             if (list[i][j] == '\t') {
 950                 list[i][j] = '\0';
 951             }
 952         }
 953         if (list[l] != NULL) {
 954             l++;
 955         }
 956     }
 957
 958     for (i = 0; i < NB_FUNCTIONS; i++) {
 959         list[l] = strdup ((functions + i)->keyword);
 960         if (list[l] != NULL) {
 961             l++;
 962         }
 963     }
 964
 965     for (i = 0; i < NB_CONSTANTS; i++) {
 966         list[l] = strdup ((constants + i)->keyword);
 967         if (list[l] != NULL) {
 968             l++;
 969         }
 970     }
 971
 972     for (i = 0; i < NB_SYMBOLS; i++) {
 973         list[l] = strdup (symbols[i]);
 974         if (list[l] != NULL) {
 975             l++;
 976         }
 977     }
 978
 979     return (list);
 980 }
 981
 982 void free_completion_list (char **list)
 983 {
 984     int i;
 985
 986     if (list) {
 987         for (i = 0; i < NB_OPERATORS + NB_FUNCTIONS + NB_CONSTANTS + NB_SYMBOLS + 1; i++) {
 988             if (list[i] != NULL) {
 989                 free (list[i]);
 990             }
 991         }
 992         free (list);
 993     }
 994 }
 995
 996 /* vim: set ts=4 sw=4 et: */