parser.c

   1 #include <malloc.h>
   2 #include <math.h>
   3 #include <stdio.h>
   4 #include <stdlib.h>
   5 #include <string.h>
   6
   7 #include "debug.h"
   8
   9 #include "parser.h"
  10
  11 /* global variables */
  12
  13 double answer = 0;
  14
  15 #define DEFAULT_STORAGE_SIZE 10
  16 int storage_size = -1;
  17
  18 double *storage = NULL;
  19
  20 #define DEFAULT_FORMAT "=> %.6g\n"
  21 char *format = NULL;
  22 char *minform = NULL;
  23
  24 workspace_t *programs = NULL;
  25 int nb_programs = 0;
  26
  27 /* compare codes */
  28
  29 int codecmp (char *ref, char *str)
  30 {
  31     int sig;
  32
  33     while (*ref != '\0') {
  34         if (*ref == '\t') {
  35              sig = (*str == '.') ? -1 : ((*str >= '0') && (*str <= '9'));
  36         } else {
  37             sig = *str - *ref;
  38         }
  39         if (sig != 0) {
  40             return (sig > 0) ? 1 : -1;
  41         }
  42         str++;
  43         ref++;
  44     }
  45
  46     return 0;
  47 }
  48
  49 /* allocate new element */
  50
  51 element_t *newelement (func_t function, int nbops, int prio)
  52 {
  53     element_t *new = (element_t *) calloc (1, sizeof (element_t));
  54     if (new == NULL) {
  55         VERBOSE (ERROR, fprintf (stderr, "can't allocate memory\n"));
  56         exit (1);
  57     }
  58     if (nbops) {
  59         new->ops = (element_t **) calloc (nbops, sizeof (element_t *));
  60         if (new->ops == NULL) {
  61             VERBOSE (ERROR, fprintf (stderr, "can't allocate memory\n"));
  62             exit (1);
  63         }
  64     }
  65     new->func = function;
  66     new->nbops = nbops;
  67     new->prio = prio;
  68
  69     return new;
  70 }
  71
  72 /* desallocate element */
  73
  74 void delelement (element_t *root)
  75 {
  76     if ((root != NULL) && (root != ERROR_OP)) {
  77         int i;
  78         for (i = 0; i < root->nbops; i++) {
  79             if ((root->ops[i] != NULL) && (root->ops[i] != ERROR_OP)) {
  80                 delelement (root->ops[i]);
  81             }
  82         }
  83         if (root->nbops) {
  84             free (root->ops);
  85         }
  86         free (root);
  87     }
  88 }
  89
  90 /* duplicate element */
  91
  92 element_t *dupelement (element_t *root)
  93 {
  94     element_t *tmp = NULL;
  95     int i;
  96
  97     if ((root == NULL) || (root == ERROR_OP)) {
  98         return root;
  99     }
 100     tmp = newelement (root->func, root->nbops, root->prio);
 101     tmp->value = root->value;
 102     for (i = 0; i < root->nbops; i++) {
 103         tmp->ops[i] = dupelement (root->ops[i]);
 104     }
 105     return tmp;
 106 }
 107
 108 /* functions */
 109
 110 #define NB_OPERATORS 14
 111 keyword_t operators[NB_OPERATORS] = {
 112     { "+\t", Add, 2, 1, 1},
 113     { "-\t", Sub, 2, 1, 1},
 114     { "*",   Mul, 2, 1, 2},
 115     { "/",   Div, 2, 1, 2},
 116     { "%",   Mod, 2, 1, 3},
 117     { "^",   Pow, 2, 1, 4},
 118     { "==",  Equal, 2, 2, -1},
 119     { "!=",  Diff, 2, 2, -1},
 120     { ">=",  Ge, 2, 2, -1},
 121     { "<=",  Le, 2, 2, -1},
 122     { ">",   Gt, 2, 1, -1},
 123     { "<",   Lt, 2, 1, -1},
 124     { "&",   And, 2, 1, -2},
 125     { "|",   Or, 2, 1, -2}
 126 };
 127
 128 #define NB_FUNCTIONS 31
 129 keyword_t functions[NB_FUNCTIONS] = {
 130     { "sqrt", Sqr, 1, 4, 5},
 131     { "pow",  Pow, 2, 3, 5},
 132     { "cos",  Cos, 1, 3, 5},
 133     { "sin",  Sin, 1, 3, 5},
 134     { "tan",  Tan, 1, 3, 5},
 135     { "acos", Acos, 1, 4, 5},
 136     { "asin", Asin, 1, 4, 5},
 137     { "atan", Atan, 1, 4, 5},
 138     { "log",  Log, 1, 3, 5},
 139     { "exp",  Exp, 1, 3, 5},
 140     { "abs",  Abs, 1, 3, 5},
 141     { "floor", Floor, 1, 5, 5},
 142     { "ceil", Ceil, 1, 4, 5},
 143     { "sto",  Store, 2, 3, 5},
 144     { "rcl",  Recall, 1, 3, 5},
 145     { "inc",  Inc, 1, 3, 5},
 146     { "dec",  Dec, 1, 3, 5},
 147     { "disp", Disp, 0, 4, 9},
 148     { "mem",  Mem, 1, 3, 9},
 149     { "clr",  Clear, 0, 3, 9},
 150     { "quit", Quit, 0, 4, 9},
 151     { "help", Help, 0, 4, 9},
 152     { "!",    Not, 1, 1, 6},
 153     { "cond", Cond, 3, 4, 5},
 154     { "while", While, 2, 5, 5},
 155     { "print", Print, 1, 5, 5},
 156     { "prog", Prog, 3, 4, 9},
 157     { "call", Call, 10, 4, 5},
 158     { "ls",   List, 0, 2, 9},
 159     { "edit", Edit, 1, 4, 9},
 160     { "del",  Del, 1, 3, 9}
 161 };
 162
 163 #define NB_CONSTANTS 3
 164 keyword_t constants[NB_CONSTANTS] = {
 165     { "ans", Ans, 0, 3, 5},
 166     { "e",   E, 0, 1, 5},
 167     { "pi",  Pi, 0, 2, 5}
 168 };
 169
 170 #define NB_SYMBOLS 4
 171 char *symbols[NB_SYMBOLS] = {
 172     "(", ")", "{", "}"
 173 };
 174
 175 /* subparser function */
 176
 177 element_t *subparser (element_t **proot, char **pstr, func_t func, int nbops, int prio)
 178 {
 179     element_t *new = newelement (func, nbops, prio);
 180     new->ops[0] = *proot;
 181     new->ops[1] = parser (*pstr, pstr, new->prio);
 182     if ((new->ops[1] == NULL) || ((new->ops[1] != ERROR_OP) && (new->ops[1]->prio == 9))) {
 183         delelement (new->ops[1]);
 184         new->ops[1] = ERROR_OP;
 185     }
 186     if (new->ops[1] == ERROR_OP) {
 187         delelement (new);
 188         *proot = NULL;
 189         return ERROR_OP;
 190     }
 191     *proot = newelement (Val, 1, 5);
 192     (*proot)->ops[0] = new;
 193
 194     return *proot;
 195 }
 196
 197 /* parser function */
 198
 199 element_t *parser (char *str, char **next, int prio)
 200 {
 201     element_t *root = NULL;
 202     int i;
 203
 204     VERBOSE (DEBUG, fprintf (stdout, "Starting parsing\n"));
 205
 206     /* main loop */
 207     while (*str != '\0') {
 208         int found = 0;
 209         element_t *new = NULL;
 210         VERBOSE (INFO, fprintf (stdout, "Processing: %s\n", str));
 211
 212         /* end without printing */
 213
 214         if (*str == ';') {
 215             if (root) {
 216                 root->hidden = 1;
 217             }
 218             break;
 219         }
 220
 221         /* skip spaces and tabs */
 222
 223         if ((*str == ' ') || (*str == '\t')) {
 224             str++;
 225             continue;
 226         }
 227
 228         /* check for open brace */
 229
 230         if (*str == '{') {
 231             VERBOSE (DEBUG, fprintf (stdout, "start processing brace\n"));
 232             if (root != NULL) {
 233                 delelement (root);
 234                 return ERROR_OP;
 235             }
 236             element_t **prog = NULL;
 237             new = newelement (Code, 0, 5);
 238             root = new;
 239             prog = &root;
 240
 241             do {
 242                 new = parser (str + 1, &str, 0);
 243                 if ((new == NULL) || ((new != ERROR_OP) && (new->prio == 9))) {
 244                     delelement (new);
 245                     new = ERROR_OP;
 246                 }
 247                 if (new == ERROR_OP) {
 248                     delelement (root);
 249                     return ERROR_OP;
 250                 }
 251                 element_t *newprog = newelement (Code, (*prog)->nbops + 1, 5);
 252                 for (i = 0; i < (*prog)->nbops; i++) {
 253                     newprog->ops[i] = (*prog)->ops[i];
 254                     (*prog)->ops[i] = NULL;
 255                 }
 256                 newprog->ops[(*prog)->nbops] = new;
 257                 delelement (*prog);
 258                 (*prog) = newprog;
 259             } while (*str == ',');
 260
 261             if (*str != '}') {
 262                 delelement (root);
 263                 return ERROR_OP;
 264             }
 265             str++;
 266             VERBOSE (DEBUG, fprintf (stdout, "stop processing brace\n"));
 267             continue;
 268         }
 269
 270         /* check for open bracket */
 271
 272         if (*str == '(') {
 273             VERBOSE (DEBUG, fprintf (stdout, "start processing bracket\n"));
 274             if (root) {
 275                 do {
 276                     found = 0;
 277                     new = parser (str + 1, &str, 0);
 278                     if ((new == NULL) || ((new != ERROR_OP) && (new->prio == 9))) {
 279                         delelement (new);
 280                         new = ERROR_OP;
 281                     }
 282                     if ((new == NULL) || (new == ERROR_OP)) {
 283                         delelement (root);
 284                         return ERROR_OP;
 285                     }
 286                     for (i = 0; i < root->nbops; i++) {
 287                         if (root->ops[i] == NULL) {
 288                             root->ops[i] = new;
 289                             found = 1;
 290                             break;
 291                         }
 292                     }
 293                     if (!found) {
 294                         delelement (new);
 295                         delelement (root);
 296                         return ERROR_OP;
 297                     }
 298                 } while (*str == ',');
 299             } else {
 300                 root = newelement (Val, 1, 5);
 301                 new = parser (str + 1, &str, 0);
 302                 if ((new == NULL) || ((new != ERROR_OP) && (new->prio == 9))) {
 303                     delelement (new);
 304                     new = ERROR_OP;
 305                 }
 306                 if ((new == NULL) || (new == ERROR_OP) || (*str == ',')) {
 307                     delelement (new);
 308                     delelement (root);
 309                     return ERROR_OP;
 310                 }
 311                 root->ops[0] = new;
 312             }
 313             if (*str != ')') {
 314                 delelement (root);
 315                 return ERROR_OP;
 316             }
 317             str++;
 318             VERBOSE (DEBUG, fprintf (stdout, "stop processing bracket\n"));
 319             continue;
 320         }
 321
 322         /* check for closing bracket, closing brace or koma */
 323
 324         if ((*str == ')') || (*str == '}') || (*str == ',')) {
 325             if (prio == -9) {
 326                 delelement (root);
 327                 return ERROR_OP;
 328             }
 329             if (next != NULL) {
 330                 *next = str;
 331             }
 332             return root;
 333         }
 334
 335         /* look for operators */
 336
 337         for (i = 0; i < NB_OPERATORS; i++) {
 338             keyword_t *operator = operators + i;
 339             if (codecmp (operator->keyword, str) == 0) {
 340                 VERBOSE (DEBUG, fprintf (stdout, "start processing operator\n"));
 341                 if (root) {
 342                     if ((prio) && (prio > operator->prio)) {
 343                         VERBOSE (DEBUG, fprintf (stdout, "stop because operator priority\n"));
 344                         *next = str;
 345                         return root;
 346                     }
 347                     str += operator->offset;
 348                     VERBOSE (INFO, fprintf (stdout, "Oper: %d\n", operator->func));
 349                     if (subparser (&root, &str, operator->func, operator->nbops, operator->prio) == ERROR_OP) {
 350                         delelement (root);
 351                         return ERROR_OP;
 352                     }
 353                 } else if (*str == '-') {
 354                     root = newelement (Sig, 1, 9);
 355                 } else {
 356                     return ERROR_OP;
 357                 }
 358                 found = 1;
 359                 VERBOSE (DEBUG, fprintf (stdout, "stop processing operator\n"));
 360                 break;
 361             }
 362         }
 363         if (found) {
 364             continue;
 365         }
 366
 367         /* look for functions */
 368
 369         for (i = 0; i < NB_FUNCTIONS; i++) {
 370             keyword_t *function = functions + i;
 371             if (codecmp (function->keyword, str) == 0) {
 372                 VERBOSE (DEBUG, fprintf (stdout, "start processing function\n"));
 373                 if (root == NULL) {
 374                     VERBOSE (INFO, fprintf (stdout, "Func: %d\n", function->func));
 375                     root = newelement (function->func, function->nbops, function->prio);
 376                 } else {
 377                     delelement (root);
 378                     return ERROR_OP;
 379                 }
 380                 str += function->offset;
 381                 found = 1;
 382                 VERBOSE (DEBUG, fprintf (stdout, "stop processing function\n"));
 383                 break;
 384             }
 385         }
 386         if (found) {
 387             continue;
 388         }
 389
 390         /* look for constant */
 391
 392         for (i = 0; i < NB_CONSTANTS; i++) {
 393             keyword_t *constant = constants + i;
 394             if (codecmp (constant->keyword, str) == 0) {
 395                 VERBOSE (DEBUG, fprintf (stdout, "start processing constant\n"));
 396                 if (root == NULL) {
 397                     VERBOSE (INFO, fprintf (stdout, "Const: %d\n", constant->func));
 398                     root = newelement (constant->func, constant->nbops, constant->prio);
 399                 } else {
 400                     delelement (root);
 401                     return ERROR_OP;
 402                 }
 403                 str += constant->offset;
 404                 found = 1;
 405                 VERBOSE (DEBUG, fprintf (stdout, "stop processing constant\n"));
 406                 break;
 407             }
 408         }
 409         if (found) {
 410             continue;
 411         }
 412
 413         /* look for number */
 414
 415         if (((*str >= '0') && (*str <= '9')) ||
 416             (*str == '.') || (*str == '+') || (*str == '-')) {
 417             VERBOSE (DEBUG, fprintf (stdout, "start processing value\n"));
 418             char *pt;
 419             double value = strtod (str, &pt);
 420             VERBOSE (INFO, fprintf (stdout, "Value: %f\n", value));
 421             if (str != pt) {
 422                 if ((root == NULL) || (root->prio == 6)) {
 423                     new = newelement (Val, 1, 5);
 424                     new->value = value;
 425                     if (root == NULL) {
 426                         root = new;
 427                     } else {
 428                         for (i = 0; i < root->nbops; i++) {
 429                             if (root->ops[i] == NULL) {
 430                                 root->ops[i] = new;
 431                                 found = 1;
 432                                 break;
 433                             }
 434                         }
 435                         if (!found) {
 436                             delelement (new);
 437                             delelement (root);
 438                             return ERROR_OP;
 439                         }
 440                     }
 441                     str = pt;
 442                 } else if ((*str == '+') || (*str == '-')) {
 443                     if ((prio) && (prio > 1)) {
 444                         VERBOSE (DEBUG, fprintf (stdout, "stop because operator priority\n"));
 445                         *next = str;
 446                         return root;
 447                     }
 448                     if (subparser (&root, &str, Add, 2, 1) == ERROR_OP) {
 449                         delelement (root);
 450                         return ERROR_OP;
 451                     }
 452                 } else {
 453                     delelement (root);
 454                     return ERROR_OP;
 455                 }
 456                 found = 1;
 457             }
 458             VERBOSE (DEBUG, fprintf (stdout, "stop processing value\n"));
 459         }
 460
 461         /* error */
 462
 463         if (!found) {
 464             delelement (root);
 465             return ERROR_OP;
 466         }
 467
 468     }
 469
 470     if (next != NULL) {
 471         *next = str;
 472     }
 473
 474     return root;
 475 }
 476
 477 /* print element tree */
 478
 479 void print_element (element_t *root, int level)
 480 {
 481     char *func = NULL;
 482     int i;
 483
 484     if ((root == NULL) || (root == ERROR_OP)) {
 485         return;
 486     }
 487
 488     for (i = 0; i < level; i++) {
 489         fprintf (stdout, " ");
 490     }
 491
 492     switch (root->func) {
 493     case Val: func = "Value"; break;
 494     case Sig: func = "Sign"; break;
 495     case Add: func = "Addition"; break;
 496     case Sub: func = "Subtraction"; break;
 497     case Mul: func = "Multiplication"; break;
 498     case Div: func = "Division"; break;
 499     case Mod: func = "Modulo"; break;
 500     case Pow: func = "Power"; break;
 501     case Sqr: func = "Square Root"; break;
 502     case Cos: func = "Cosine"; break;
 503     case Sin: func = "Sine"; break;
 504     case Tan: func = "Tangent"; break;
 505     case Acos: func = "Arc Cosine"; break;
 506     case Asin: func = "Arc Sine"; break;
 507     case Atan: func = "Arc Tangent"; break;
 508     case Log: func = "Logarithm"; break;
 509     case Exp: func = "Exponantial"; break;
 510     case Abs: func = "Absolute value"; break;
 511     case Ceil: func = "Ceil value"; break;
 512     case Floor: func = "Floor value"; break;
 513     case Store: func = "Store"; break;
 514     case Recall: func = "Recall"; break;
 515     case Inc: func = "Increase"; break;
 516     case Dec: func = "Decrease"; break;
 517     case Disp: func = "Display"; break;
 518     case Mem: func = "Memory"; break;
 519     case Clear: func = "Clear"; break;
 520     case Quit: func = "Quit"; break;
 521     case Help: func = "Help"; break;
 522     case Ans: func = "Ans"; break;
 523     case Pi: func = "Pi"; break;
 524     case E: func = "E"; break;
 525     case Equal: func = "Equal"; break;
 526     case Diff: func = "Different"; break;
 527     case Ge: func = "Greater or equal"; break;
 528     case Le: func = "Lesser or equal"; break;
 529     case Gt: func = "Greater"; break;
 530     case Lt: func = "Lesser"; break;
 531     case And: func = "And"; break;
 532     case Or: func = "Or"; break;
 533     case Not: func = "Not"; break;
 534     case Cond: func = "Condition"; break;
 535     case While: func = "While"; break;
 536     case Code: func = "Code"; break;
 537     case Print: func = "Print"; break;
 538     case Prog: func = "Program"; break;
 539     case Call: func = "Call"; break;
 540     case List: func = "List"; break;
 541     case Edit: func = "Edit"; break;
 542     case Del: func = "Del"; break;
 543     }
 544
 545     fprintf (stdout, "Function: %s\n", func);
 546
 547     if ((root->func == Val) && (root->ops[0] == NULL)) {
 548         for (i = 0; i < level; i++) {
 549             fprintf (stdout, " ");
 550         }
 551         fprintf (stdout, "value: %f\n", root->value);
 552     } else {
 553         for (i = 0; i < root->nbops; i++) {
 554             print_element (root->ops[i], level + 1);
 555         }
 556     }
 557 }
 558
 559 /* storage functions */
 560
 561 void memory (int nb)
 562 {
 563     int i, l;
 564     double *tmp = NULL;
 565     if (nb != storage_size) {
 566         l = (nb < storage_size) ? nb : storage_size;
 567         tmp = (double *) calloc (nb, sizeof (double));
 568         if (tmp == NULL) {
 569             VERBOSE (ERROR, fprintf (stderr, "can't allocate memory\n"));
 570             exit (1);
 571         }
 572         for (i = 0; i < l; i++) {
 573             tmp[i] = storage[i];
 574         }
 575         if (storage != NULL) {
 576             free (storage);
 577         }
 578         storage = tmp;
 579         storage_size = nb;
 580     }
 581 }
 582
 583 double store (int index, double value)
 584 {
 585     if (storage_size == -1) {
 586         memory (DEFAULT_STORAGE_SIZE);
 587     }
 588     if ((index > 0) && (index <= storage_size)) {
 589         storage[index - 1] = value;
 590     } else {
 591         VERBOSE (WARNING, fprintf (stdout, "invalid index (%d) [%d, %d]\n", index, (storage_size) ? 1 : 0, storage_size));
 592     }
 593     return value;
 594 }
 595
 596 double recall (int index)
 597 {
 598     if (storage_size == -1) {
 599         memory (DEFAULT_STORAGE_SIZE);
 600     }
 601     if ((index > 0) && (index <= storage_size)) {
 602         return storage[index - 1];
 603     } else {
 604         VERBOSE (WARNING, fprintf (stdout, "invalid index (%d) [%d, %d]\n", index, (storage_size) ? 1 : 0, storage_size));
 605     }
 606     return 0;
 607 }
 608
 609 double increase (int index)
 610 {
 611     if (storage_size == -1) {
 612         memory (DEFAULT_STORAGE_SIZE);
 613     }
 614     if ((index > 0) && (index <= storage_size)) {
 615         return storage[index - 1]++;
 616     } else {
 617         VERBOSE (WARNING, fprintf (stdout, "invalid index (%d) [%d, %d]\n", index, (storage_size) ? 1 : 0, storage_size));
 618     }
 619     return 0;
 620 }
 621
 622 double decrease (int index)
 623 {
 624     if (storage_size == -1) {
 625         memory (DEFAULT_STORAGE_SIZE);
 626     }
 627     if ((index > 0) && (index <= storage_size)) {
 628         return storage[index - 1]--;
 629     } else {
 630         VERBOSE (WARNING, fprintf (stdout, "invalid index (%d) [%d, %d]\n", index, (storage_size) ? 1 : 0, storage_size));
 631     }
 632     return 0;
 633 }
 634
 635 void display (void)
 636 {
 637     int i;
 638     if (storage_size == -1) {
 639         memory (DEFAULT_STORAGE_SIZE);
 640     }
 641     fprintf (stdout, "storage:");
 642     for (i = 0; i < storage_size; i++) {
 643         fprintf (stdout, " ");
 644         fprintf (stdout, minform, storage[i]);
 645     }
 646     fprintf (stdout, "\n");
 647 }
 648
 649 void clear ()
 650 {
 651     int i;
 652     for (i = 0; i < storage_size; i++) {
 653         storage[i] = 0;
 654     }
 655 }
 656
 657 /* While do function */
 658
 659 double while_do (element_t *cond, element_t *action)
 660 {
 661     double ret = 0;
 662     element_t *temp = NULL;
 663
 664     VERBOSE (DEBUG, fprintf (stdout, "starting while loop\n"));
 665     while (1) {
 666         VERBOSE (DEBUG, fprintf (stdout, "loop...\n"));
 667
 668         temp = dupelement (cond);
 669         if (!evaluate_element (temp, 0)) {
 670             break;
 671         }
 672         if (action) {
 673             temp = dupelement (action);
 674             ret = evaluate_element (temp, 0);
 675         }
 676     }
 677
 678     VERBOSE (DEBUG, fprintf (stdout, "ending while loop\n"));
 679
 680     return ret;
 681 }
 682
 683 /* program function */
 684
 685 double execute_code (element_t **prog, int nbcalls)
 686 {
 687     double ret = 0;
 688     int i;
 689     for (i = 0; i < nbcalls; i++) {
 690         ret = evaluate_element (prog[i], 0);
 691         prog[i] = NULL;
 692     }
 693     return ret;
 694 }
 695
 696 /* print function */
 697
 698 void set_format (char *prompt, int precision)
 699 {
 700     char buffer[128] = {0};
 701     free_format ();
 702     sprintf (buffer, "%s%%.%dg\n", prompt, precision);
 703     format = strdup (buffer);
 704     sprintf (buffer, "%%.%dg", precision);
 705     minform = strdup (buffer);
 706 }
 707
 708 void free_format ()
 709 {
 710     if (format) {
 711         free (format);
 712         format = NULL;
 713     }
 714     if (minform) {
 715         free (minform);
 716         minform = NULL;
 717     }
 718 }
 719
 720 double print (double value)
 721 {
 722     fprintf (stdout, format ? format : DEFAULT_FORMAT, value);
 723     fflush (stdout);
 724     return value;
 725 }
 726
 727 /* quit function */
 728
 729 void quit (void)
 730 {
 731     fprintf (stdout, "bye\n");
 732     exit (0);
 733 }
 734
 735 /* program function */
 736
 737 void prog (int id, int nbmems, element_t *root)
 738 {
 739     int i, n = -1;
 740
 741     if (programs == NULL) {
 742
 743         /* initial memory allocation */
 744         programs = (workspace_t *) calloc (1, sizeof (workspace_t));
 745         if (programs == NULL) {
 746             VERBOSE (ERROR, fprintf (stderr, "can't allocate memory\n"));
 747             exit (1);
 748         }
 749         nb_programs = 1;
 750         n = 0;
 751
 752     } else {
 753
 754         /* look for existing program */
 755         for (i = 0; i < nb_programs; i++) {
 756             if ((programs + i)->id == id) {
 757                 n = i;
 758                 break;
 759             }
 760         }
 761         if (n == -1) {
 762
 763             /* new program */
 764             n = nb_programs++;
 765             programs = (workspace_t *) realloc (programs, nb_programs * sizeof (workspace_t));
 766         } else {
 767
 768             /* clean old program */
 769             if ((programs + n)->storage) {
 770                 free ((programs + n)->storage);
 771             }
 772             if ((programs + n)->root) {
 773                 delelement ((programs + n)->root);
 774             }
 775         }
 776     }
 777
 778     /* set program */
 779     (programs + n)->id = id;
 780     (programs + n)->answer = 0;
 781     (programs + n)->storage = (double *) calloc (nbmems, sizeof (double));
 782     if ((programs + n)->storage == NULL) {
 783         VERBOSE (ERROR, fprintf (stderr, "can't allocate memory\n"));
 784         exit (1);
 785     }
 786     (programs + n)->storage_size = nbmems;
 787     (programs + n)->root = root;
 788 }
 789
 790 double call (int id, int nbobs, element_t **ops)
 791 {
 792     workspace_t tmp = {0};
 793     int i, n = -1;
 794     double ret = 0;
 795
 796     if (programs) {
 797         for (i = 0; i < nb_programs; i++) {
 798             if ((programs + i)->id == i) {
 799                 n = i;
 800                 break;
 801             }
 802         }
 803
 804         if (n == -1) {
 805             VERBOSE (WARNING, fprintf (stdout, "error unknown program (%d)\n", id));
 806             return 0;
 807         }
 808
 809         /* store context */
 810         tmp.answer = answer;
 811         tmp.storage = storage;
 812         tmp.storage_size = storage_size;
 813
 814         /* change context */
 815         answer = 0;
 816         storage = (programs + i)->storage;
 817         storage_size = (programs + i)->storage_size;
 818         if (nbobs > storage_size) {
 819             storage = realloc (storage, nbobs * sizeof (double));
 820             storage_size = nbobs;
 821         }
 822         for (i = 0; i < nbobs; i++) {
 823             store (i + 1, evaluate_element (ops[i], 0));
 824         }
 825
 826         /* evaluate program */
 827         element_t *element = dupelement ((programs + n)->root);
 828         ret = evaluate_element (element, 0);
 829
 830         /* restore context */
 831         answer = tmp.answer;
 832         storage = tmp.storage;
 833         storage_size = tmp.storage_size;
 834     }
 835
 836     return ret;
 837 }
 838
 839 void list ()
 840 {
 841     int i;
 842     if (programs != NULL) {
 843         fprintf (stdout, "programs:");
 844         for (i = 0; i < nb_programs; i++) {
 845             fprintf (stdout, " %d", (programs + i)->id);
 846         }
 847         fprintf (stdout, "\n");
 848     }
 849 }
 850
 851 void edit (int id)
 852 { }
 853
 854 void del (int id)
 855 { }
 856
 857 /* help message */
 858
 859 void help (void)
 860 {
 861     fprintf (stdout, "calc is a simple calculator\n\n");
 862     fprintf (stdout, "supported operators:");
 863     fprintf (stdout, " + - * / %% ^\n");
 864     fprintf (stdout, "camparison operators:");
 865     fprintf (stdout, " == != >= <= > <\n");
 866     fprintf (stdout, "logical operators:");
 867     fprintf (stdout, " & | !\n");
 868     fprintf (stdout, "mathematic functions:");
 869     fprintf (stdout, " pow sqrt log exp\n");
 870     fprintf (stdout, "trig. func.:");
 871     fprintf (stdout, " cos sin tan acos asin atan\n");
 872     fprintf (stdout, "supported functions:");
 873     fprintf (stdout, " abs ceil floor\n");
 874     fprintf (stdout, "storage functions:");
 875     fprintf (stdout, " mem sto rcl inc dec disp\n");
 876     fprintf (stdout, "prog. functions:");
 877     fprintf (stdout, " cond while print {} ;\n");
 878     fprintf (stdout, "misc. functions:");
 879     fprintf (stdout, " quit help\n");
 880     fprintf (stdout, "supported constants:");
 881     fprintf (stdout, " e pi\n");
 882 }
 883
 884 /* evaluate element tree */
 885
 886 #define MASK_SUB 0x1
 887 #define MASK_DIV 0x2
 888
 889 double evaluate_element (element_t *root, char mask)
 890 {
 891     double op0 = 0, op1 = 0;
 892     char nextmask = mask;
 893
 894     if ((root == NULL) || (root == ERROR_OP)) {
 895         VERBOSE (WARNING, fprintf (stdout, "error while evaluating\n"));
 896         return 0;
 897     }
 898
 899     /* mask to manage sub operator sub and div */
 900     switch (root->func) {
 901     case Add:
 902         nextmask &= ~MASK_SUB;
 903         nextmask &= ~MASK_DIV;
 904         break;
 905     case Sub:
 906         nextmask |= MASK_SUB;
 907         nextmask &= ~MASK_DIV;
 908         break;
 909     case Mul:
 910         nextmask &= ~MASK_DIV;
 911         break;
 912     case Div:
 913         nextmask |= MASK_DIV;
 914         break;
 915     default:
 916         nextmask = mask;
 917     }
 918
 919     switch (root->func) {
 920     case Val:
 921     case Sig:
 922         op0 = (root->ops[0]) ? evaluate_element (root->ops[0], nextmask) : root->value;
 923         break;
 924     case Add:
 925     case Sub:
 926     case Mul:
 927     case Div:
 928     case Mod:
 929     case Pow:
 930     case Store:
 931     case Equal:
 932     case Diff:
 933     case Ge:
 934     case Le:
 935     case Gt:
 936     case Lt:
 937     case And:
 938     case Or:
 939     case Prog:
 940         if (root->ops[1]) {
 941             op1 = evaluate_element (root->ops[1], nextmask);
 942         } else if (root->func != Store) {
 943             VERBOSE (WARNING, fprintf (stdout, "error while evaluating (op[1])\n"));
 944             return 0;
 945         }
 946         /* fallthrough */
 947     case Sqr:
 948     case Cos:
 949     case Sin:
 950     case Tan:
 951     case Acos:
 952     case Asin:
 953     case Atan:
 954     case Log:
 955     case Exp:
 956     case Abs:
 957     case Ceil:
 958     case Floor:
 959     case Recall:
 960     case Inc:
 961     case Dec:
 962     case Not:
 963     case Mem:
 964     case Cond:
 965     case Call:
 966     case List:
 967     case Edit:
 968     case Del:
 969         if (root->ops[0]) {
 970             op0 = evaluate_element (root->ops[0], 0);
 971         } else {
 972             VERBOSE (WARNING, fprintf (stdout, "error while evaluating (op[0])\n"));
 973             return 0;
 974         }
 975         break;
 976     case Disp:
 977     case Clear:
 978     case Quit:
 979     case Help:
 980     case Ans:
 981     case Pi:
 982     case E:
 983     case Code:
 984         break;
 985     case While:
 986         if (root->ops[0] == NULL) {
 987             VERBOSE (WARNING, fprintf (stdout, "error while evaluating (op[0])\n"));
 988             return 0;
 989         }
 990         break;
 991     case Print:
 992         op0 = (root->ops[0]) ? evaluate_element (root->ops[0], 0) : answer;
 993         break;
 994     }
 995
 996     switch (root->func) {
 997     case Val: return op0;
 998     case Sig: return -op0;
 999     case Add: return ((mask & MASK_SUB) == 0) ? op0 + op1 : op0 - op1;
1000     case Sub: return ((mask & MASK_SUB) == 0) ? op0 - op1 : op0 + op1;
1001     case Mul: return ((mask & MASK_DIV) == 0) ? op0 * op1 : op0 / op1;
1002     case Div: return ((mask & MASK_DIV) == 0) ? op0 / op1 : op0 * op1;
1003     case Mod: return fmod (op0, op1);
1004     case Pow: return pow (op0, op1);
1005     case Sqr: return sqrt (op0);
1006     case Cos: return cos (op0);
1007     case Sin: return sin (op0);
1008     case Tan: return tan (op0);
1009     case Acos: return acos (op0);
1010     case Asin: return asin (op0);
1011     case Atan: return atan (op0);
1012     case Log: return log (op0);
1013     case Exp: return exp (op0);
1014     case Abs: return fabs (op0);
1015     case Ceil: return ceil (op0);
1016     case Floor: return floor (op0);
1017     case Store: return store ((int)op0, (op1) ? op1 : answer);
1018     case Recall: return recall ((int)op0);
1019     case Inc: return increase ((int)op0);
1020     case Dec: return decrease ((int)op0);
1021     case Disp: display (); break;
1022     case Mem: memory ((int)op0); break;
1023     case Clear: clear (); break;
1024     case Quit: quit (); break;
1025     case Help: help (); break;
1026     case Ans: return answer;
1027     case Pi: return M_PI;
1028     case E: return M_E;
1029     case Equal: return op0 == op1;
1030     case Diff: return op0 != op1;
1031     case Ge: return op0 >= op1;
1032     case Le: return op0 <= op1;
1033     case Gt: return op0 > op1;
1034     case Lt: return op0 < op1;
1035     case And: return (op0 != 0) && (op1 != 0);
1036     case Or: return (op0 != 0) || (op1 != 0);
1037     case Not: return (op0 == 0);
1038     case Cond:
1039         if ((op0) && (root->ops[1])) {
1040             return evaluate_element (root->ops[1], 0);
1041         } else if ((!op0) && (root->ops[2])) {
1042             return evaluate_element (root->ops[2], 0);
1043         } else {
1044             return 0;
1045         }
1046     case While: return while_do (root->ops[0], root->ops[1]);
1047     case Code: return execute_code (root->ops, root->nbops);
1048     case Print: return print (op0);
1049     case Prog: prog ((int)op0, (int)op1, root->ops[2]); break;
1050     case Call: return call ((int)op0, root->nbops + 1, root->ops + 1);
1051     case List: list (); break;
1052     case Edit: edit ((int)op0); break;
1053     case Del: del ((int)op0); break;
1054     }
1055
1056     return 0;
1057 }
1058
1059 char **generate_completion_list ()
1060 {
1061     int i, j, l = 0;
1062     char **list = (char **) calloc (NB_OPERATORS + NB_FUNCTIONS + NB_CONSTANTS + NB_SYMBOLS + 1, sizeof (char *));
1063     if (list == NULL) {
1064         VERBOSE (ERROR, fprintf (stderr, "can't allocate memory\n"));
1065         exit (1);
1066     }
1067
1068     for (i = 0; i < NB_OPERATORS; i++) {
1069         list[l] = strdup ((operators + i)->keyword);
1070         for (j = 0; j < (int)strlen (list[l]); j++) {
1071             if (list[i][j] == '\t') {
1072                 list[i][j] = '\0';
1073             }
1074         }
1075         if (list[l] != NULL) {
1076             l++;
1077         }
1078     }
1079
1080     for (i = 0; i < NB_FUNCTIONS; i++) {
1081         list[l] = strdup ((functions + i)->keyword);
1082         if (list[l] != NULL) {
1083             l++;
1084         }
1085     }
1086
1087     for (i = 0; i < NB_CONSTANTS; i++) {
1088         list[l] = strdup ((constants + i)->keyword);
1089         if (list[l] != NULL) {
1090             l++;
1091         }
1092     }
1093
1094     for (i = 0; i < NB_SYMBOLS; i++) {
1095         list[l] = strdup (symbols[i]);
1096         if (list[l] != NULL) {
1097             l++;
1098         }
1099     }
1100
1101     return (list);
1102 }
1103
1104 void free_completion_list (char **list)
1105 {
1106     int i;
1107
1108     if (list) {
1109         for (i = 0; i < NB_FUNCTIONS + NB_CONSTANTS; i++) {
1110             if (list[i] != NULL) {
1111                 free (list[i]);
1112             }
1113         }
1114         free (list);
1115     }
1116 }
1117
1118
1119 /* vim: set ts=4 sw=4 et: */